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Tungsten functional paper (TFP), which contains 80% tungsten by weight, has radiation-shielding properties. We investigated the use of TFP for the protection of operators during interventional or therapeutic angiography. The air kerma rate of scattered radiation from a simulated patient was measured, with and without TFP, using a water-equivalent phantom and fixed C-arm fluoroscopy. Measurements were taken at the level of the operator's eye, chest, waist, and knee, with a variable number of TFP sheets used for shielding. A Monte Carlo simulation was also utilized to analyze the dose rate delivered with and without the TFP shielding. In cine mode, when the number of TFP sheets was varied through 1, 2, 3, 5, and 10, the respective reduction in the air kerma rate relative to no TFP shielding was as follows: at eye level, 24.9%, 29.9%, 41.6%, 50.4%, and 56.2%; at chest level, 25.3%, 33.1%, 34.9%, 46.1%, and 44.3%; at waist level, 45.1%, 57.0%, 64.4%, 70.7%, and 75.2%; and at knee level, 2.1%, 2.2%, 2.1%, 2.1%, and 2.1%. In fluoroscopy mode, the respective reduction in the air kerma rate relative to no TFP shielding was as follows: at eye level, 24.8%, 30.3%, 34.8%, 51.1%, and 58.5%; at chest level, 25.8%, 33.4%, 35.5%, 45.2%, and 44.4%; at waist level, 44.6%, 56.8%, 64.7%, 71.7%, and 77.2%; and at knee level, 2.2%, 0.0%, 2.2%, 2.8%, and 2.5%. The TFP paper exhibited good radiation-shielding properties against the scattered radiation encountered in clinical settings, and was shown to have potential application in decreasing the radiation exposure to the operator during interventional radiology. [ABSTRACT FROM AUTHOR]

Background: Ultrasound (US) is not widely used as part of the speech and language therapy (SLT) clinical toolkit. The COVID‐19 pandemic has intensified interest in US as an alternative to SLT instrumental tools such as the videofluoroscopic swallowing study (VFSS), fibreoptic endoscopic evaluation of swallowing (FEES) and endoscopic evaluation of the larynx (EEL) as a non‐invasive, non‐aerosol‐generating procedure that can be delivered at the bedside to assess swallowing and/or laryngeal function. To establish the appropriacy of routine US use, and in response to a national professional body request for a position statement, a group of expert SLTs conducted a rapid review of the literature. Aim: To explore critically the clinical utility of US as an assessment tool for swallowing and laryngeal function in adults. Methods & Procedures: A rapid review of four databases was completed to identify articles using US to assess swallowing and/or laryngeal function in adults compared with reference tests (VFSS/FEES/EEL/validated outcome measure). Screening was completed according to predefined inclusion/exclusion criteria and 10% of abstracts were rescreened to assess reliability. Data were extracted from full texts using a predeveloped form. The QUADAS‐2 tool was used for quality ratings. Information from included studies was summarized using narrative synthesis and visual illustration. Outcomes & Results: Ten papers used US to assess swallowing, and 13 to assess laryngeal function. All were peer‐reviewed primary studies across a range of clinical populations and with a wide geographical spread. Four papers had an overall low risk of bias, but the remaining 19 had at least one domain where risk of bias was judged as high or unclear. Applicability concerns were identified in all papers. The papers that used US to assess swallowing varied widely in terms of the anatomical structures assessed and methodology employed. The papers assessing laryngeal function were more homogenous in their methodology. Sensitivity and specificity data were provided for 12 of the laryngeal function papers with ranges of 64.3–100% and 48.5–100%, respectively. Conclusions & Implications: There is burgeoning evidence to support the use of US as an adjunct to SLT clinical assessment of swallowing and laryngeal function. However, the current literature does not support its use as a tool in isolation. Further research is required to establish reliability in US assessment as well as clear SLT‐driven protocols and training. What this paper addsWhat is already known on the subjectUS has demonstrated potential as an assessment tool for objective parameters of swallowing. Its use for laryngeal assessment (gross vocal fold movement) is also widely recognized within the literature. This review appraised the literature related to US as an alternative or adjunctive tool for the assessment of swallowing and laryngeal function.What this paper adds to existing knowledgeThis paper identifies that the current evidence base for US as a swallowing or laryngeal assessment tool is heterogenous and of variable quality. No study combined the assessment of swallowing and laryngeal function, and only two studies assessed more than one parameter of swallowing, limiting the clinical application of the results.What are the potential or actual clinical implications of this work?This review shows that US is a non‐invasive accessible tool that can offer a detailed focal assessment of swallowing and laryngeal function, such as hyoid displacement and vocal fold mobility. With the development of protocols, training packages and competency standards, US has the potential to be used as an adjunct to SLT assessment of swallowing and laryngeal function. There is not currently enough evidence to support the use of US as a stand‐alone tool for SLT assessment of swallowing or laryngeal function. [ABSTRACT FROM AUTHOR]

Background: Speech and language therapists (SLTs) use videofluoroscopic swallow study (VFSS) results to manage dysphagia. Yet, in some services only doctors can directly request a VFSS, potentially creating workflow inefficiencies and delaying patient access to VFSS. An alternative model, where SLTs directly refer patients for VFSS, is used in many services in the UK and Australia. However, processes for implementing and sustaining this model have not been reported. Aims: To evaluate the implementation of an SLT‐led inpatient VFSS referring model using the Consolidated Framework for Implementation Research (CFIR) to ascertain implementation barriers, facilitators and critical sustainability factors. Methods & Procedures: This implementation evaluation examined stakeholder perceptions of implementing the SLT‐led VFSS referring model via interviews of (1) SLTs who treat and refer inpatients for VFSS; (2) doctors who manage and refer inpatients for VFSS; (3) radiologists; and (4) trained VFSS referring SLTs. The CFIR was used to prospectively guide implementation planning, evaluation and outcome reporting, regarding barriers, facilitators and sustainability factors. Outcomes & Results: Implementation facilitators were (1) the advantage of SLT‐led VFSS referring over the standard model (doctors referring), in promoting high‐quality VFSS referrals; (2) compatibility of the model with the SLT skill set; (3) supportive communication networks between staff groups; and (4) engaging stakeholders throughout implementation. Adequate availability of trained VFSS referring SLTs was both a barrier and a facilitator of implementation. It was also a critical sustainability factor, along with ongoing staff education and outcome monitoring. Conclusions & Implications: The CFIR supported systematic evaluation of implementation facilitators and barriers, and adjustment of factors critical for implementing and sustaining the new model. Findings may assist other organizations to establish the SLT‐led VFSS referring model. What this paper adds: What is already known on the subject: Models where SLTs directly refer patients for VFSS have been described in the literature, with evidence of appropriate referrals and adherence to radiation safety standards. However, the process for establishing and sustaining this referring model has not been published. What this paper adds to existing knowledge: This study describes the process and outcomes of implementing an SLT‐led VFSS referring model, using the CFIR. A key advantage of the new model that facilitated implementation was the improved quality of VFSS referrals compared with the standard referring model. Important facilitating factors in the environment were the compatibility of the model with SLTs' skillset and supportive communication network between doctors and SLTs. Initially, an implementation barrier was the inadequate availability of trained SLT referrers. Using proactive implementation strategies, more referrers were trained (which was a facilitating factor for implementing and sustaining the model). What are the potential or actual clinical implications of this work?: This study highlights that successful implementation requires more than just an effective model. Features of the environment require consideration to minimize barriers and optimize facilitating factors, supported by proactive implementation strategies. Planning and evaluating implementation processes and outcomes using a standardized implementation framework such as CFIR aided understanding of barriers and facilitators for introducing the SLT‐led VFSS referring model. This process may assist other services to implement the model. [ABSTRACT FROM AUTHOR]

Background: Perceptual, cognitive and previous clinical experience may influence a novice Videofluoroscopic Swallowing Study (VFSS) analyst's trajectory towards competency. Understanding these factors may allow trainees to be better prepared for VFSS training and may allow training to be developed to accommodate differences between trainees. Aims: This study explored a range of factors previously suggested in the literature as influencing the development of novice analysts' VFSS skills. We hypothesised that knowledge of swallow anatomy and physiology, visual perceptual skills, self‐efficacy and interest, and prior clinical exposure would all influence VFSS novice analysts' skill development. Methods & Procedures: Participants were undergraduate speech pathology students recruited from an Australian university, who had completed the required theoretical units in dysphagia. Data assessing the factors of interest were collected—the participants identified anatomical structures on a still radiographic image, completed a physiology questionnaire, completed subsections of the Developmental Test of Visual Processing—Adults, self‐reported the number of dysphagia cases they managed on placement, and self‐rated their confidence and interest. Data for 64 participants relating to the factors of interest were compared with their ability to accurately identify swallowing impairments following 15 h of VFSS analytical training, using correlation and regression analysis. Outcomes & Results: Success in VFSS analytical training was best predicted by clinical exposure to dysphagia cases and the ability to identify anatomical landmarks on still radiographic images. Conclusions & Implications: Novice analysts vary in the acquisition of beginner‐level VFSS analytical skill. Our findings suggest that speech pathologists who are new to VFSS may benefit from clinical exposure to dysphagia cases, sound foundational knowledge of anatomy relevant to swallowing and the ability to see the anatomical landmarks on still radiographic images. Further research is required to equip VFSS trainers and trainees for training, to understand differences between learners during skill development. WHAT THIS PAPER ADDS: What is already known on the subject: The existing literature suggests that no vice Video fluoroscopic Swallowing Study (VFSS) analysts training may be influenced by their personal characteristics and experience. What this study adds: This study found that student clinicians, clinical exposure to dysphagia cases and their ability to identify anatomical landmarks relevant to swallowing on still radiographic images prior to training best predicted their ability to identify swallowing impairments after training. What are the clinical implications of this work?: Given the expense of training health professionals, further research is required into the factors that successfully prepare clinicians for VFSS training, including clinical exposure, foundational knowledge of anatomy relevant to swallowing and the ability to identify the anatomical landmarks on still radiographic images. [ABSTRACT FROM AUTHOR]

Background: The use of ultrasound as an adjunct to clinical swallowing evaluation provides quantitative physiological and morphological data. As a low‐risk procedure, ultrasound imaging can be performed outside of a medical setting. This is particularly important for patients living in rural areas with restricted access to a hospital. Technical advances have produced pocket‐sized ultrasound technology that is more affordable, and therefore within the fiscal reach of most allied health services. Aims: To explore the validity and reliability of pocket‐sized ultrasound technology in dysphagia assessment. Methods & Procedures: Data were acquired from 43 patients with dysphagia using the Clarius ultrasound device. Ultrasound and videofluoroscopic measures of hyoid and laryngeal displacement during liquid and puree swallowing were collected concurrently to quantify correlation and agreement between identical measures derived from the two instruments. Reliability of ultrasound was assessed for measures of hyoid and laryngeal displacement, tongue thickness, and size of the submental muscles in eight patients. Reliability was evaluated for the entire process of data acquisition including scanning and online measurement using an iPad in a clinical setting and for offline measurement on a computer screen to explore environmental influences on reliability. Outcomes & Results: Results revealed poor correlation between the measures of interest across instruments. Reliability of the entire process of data acquisition in a clinical setting was insufficient while reliability was more promising for offline measurements. Conclusions & Implications: The clinical use of pocket‐sized ultrasound devices, such as the Clarius system, for swallowing evaluation is not indicated at this time. Enhanced validity and reliability of the entire process of data acquisition are needed prior to clinical translation of such technology. WHAT THIS PAPER ADDS: What is already known on the subject: The use of ultrasound allows for radiation‐free, non‐invasive swallowing assessment. Some data suggest that ultrasound is valid and reliable in the evaluation of swallowing using standard‐sized equipment. Insufficient validity and reliability have been reported for pocket‐sized ultrasound technology in the assessment of healthy swallowing. What this paper adds to existing knowledge: This research is the first to provide validity and reliability data of the pocket‐sized Clarius technology in the evaluation of swallowing in patients with dysphagia. Insufficient validity and reliability of online data acquisition in a clinical environment were found. Reliability for offline measurement was more promising. What are the potential or actual clinical implications of this work?: The clinical use of pocket‐sized ultrasound devices, such as the Clarius system, for swallowing assessment is not indicated at this time. [ABSTRACT FROM AUTHOR]

Background: Videofluoroscopic swallow studies (VFSS) are integral to diagnosing and supporting dysphagia management. However, in many countries, only doctors are authorized to complete medical imaging request forms, in accordance with radiation safety regulations. This can impact workflow and timely access to VFSS. Enhanced scope of practice (ESP) models of care exist, where speech and language therapists (SLTs) are authorized to complete VFSS request forms. However, formal evaluations of these ESP models are currently lacking. Aims: The primary aim of this study was to examine service outcomes regarding the safety and efficiency of SLTs completing VFSS request forms compared with the medical referring model (standard care). The secondary aim was to ascertain the impacts on SLTs' daily workflow and the utility of training for SLTs to complete VFSS requests. Methods & Procedures: The study involved a mixed‐method design. First, referrals completed using standard care versus those completed under the new SLT‐led VFSS referring model were compared for efficiency (days to request completion, number of contacts between staff to complete requests and delay to VFSS appointments) and safety (compliance with radiation safety standards for requests, adverse events and change to dysphagia management to justify radiation exposure). Semi‐structured interviews were then conducted with SLT referrers (n = 7) exploring the impacts of the model on daily workflow and the utility of training. Outcomes & Results: VFSS inpatient requests were examined across a 3‐month period (n = 61 requests) using the standard model, and for 6 months (n = 109 requests) following the introduction of SLT‐led VFSS referring. Regarding efficiency, there was no significant difference between the two models, with most request forms taking less than or equal to 1 day to be completed. Adherence to radiation safety requirements was significantly greater in the SLT‐led VFSS referring model compared with the standard model (p < 0.001) in relation to the overall requisite clinical information being documented on the request forms. No adverse events occurred and 100% of VFSSs led to changed dysphagia management. Interviews of VFSS referring SLTs revealed that completing requests was not complex or onerous, and that the training equipped them well to undertake the role. Conclusions & Implications: The SLT‐led VFSS referring model was feasible for SLTs and resulted in satisfactory efficiency and greater adherence to radiation safety requirements for VFSS request forms than the standard model. Improved information on VFSS request forms provides clearer justification for the radiation procedure and helps optimize the diagnostic yield of VFSS. The evidence supports further widespread adoption of this model. What this paper adds: What is already known on the subject: Models of care permitting selected allied health professionals to refer patients for diagnostic radiology procedures have been established to achieve healthcare efficiencies. Evidence supports the safety and efficiency of physiotherapists referring to radiology. However, limited published outcome data exist regarding models of SLTs referring for radiology procedures, such as VFSS. What this paper adds to existing knowledge: This study describes the implementation of a SLT‐led VFSS inpatient referring model in a quaternary hospital and examines service outcomes. The findings reveal that VFSS request forms completed in the SLT‐led referring model had greater adherence to radiation safety standards compared with the standard referring model. Efficiency was similar across both models and there were no adverse events. Completing VFSS requests did not disrupt daily workflow for SLTs and training was effective preparation for the role. What are the potential or actual clinical implications of this work?: Results demonstrate that the SLT‐led VFSS referral model can be safely and appropriately implemented in the inpatient setting. Improved quality of information documented on request forms by SLTs increases adherence with radiation safety standards, providing clearer justification for radiation assessments and potentially eliciting more targeted diagnostic information to inform dysphagia treatment planning. These findings may support other hospital services to establish this type of referring model. [ABSTRACT FROM AUTHOR]

Purpose: We address the misconception that the typical physician dose is higher for CT fluoroscopy (CTF) procedures compared to C‐Arm procedures. Methods: We compare physician scatter doses using two methods: a literature review of reported doses and a model based on a modified form of the dose area product (DAP). We define this modified form of DAP, "cumulative absorbed DAP," as the product of the area of the x‐ray beam striking the patient, the dose rate per unit area, and the exposure time. Results: The patient entrance dose rate for C‐Arm fluoroscopy (0.2 mGy/s) was found to be 15 times lower than for CT fluoroscopy (3 mGy/s). A typical beam entrance area for C‐Arm fluoroscopy reported in the literature was found to be 10.6 × 10.6 cm (112 cm2), whereas for CTF was 0.75 × 32 cm (24 cm2). The absorbed DAP rate for C‐Arm fluoroscopy (22 mGy*cm2/s) was found to be 3.3 times lower than for CTF (72 mGy*cm2/s). The mean fluoroscopy time for C‐Arm procedures (710 s) was found to be 21 times higher than for CT fluoroscopy procedures (23 s). The cumulative absorbed DAP for C‐Arm procedures was found to be 9.4 times higher when compared to CT procedures (1.59 mGy*m2 vs. 0.17 mGy*m2). Conclusions: The higher fluoroscopy time in C‐Arm procedures leads to a much lower cumulative DAP (i.e., physician scatter dose) in CTF procedures. This result can inform interventional physicians deciding on whether to perform inter‐procedural imaging inside the room as opposed to retreating from the room. [ABSTRACT FROM AUTHOR]

Objective: C2 pedicle screw insertion is very important in posterior upper cervical surgery. The traditional screw placement technique requires us to consider both medial inclination and cephalad angle, it is difficult to operate intraoperatively. This paper is to explore a novel method of C2 pedicle screw placement compared with traditional C2 pedicle screw. Methods: A total of 44 patients diagnosed with atlantoaxial fracture or instability from May 2018 to November 2020 were involved in this retrospective study, and they were divided into C2‐PPS group (perpendicular to the coronal plane C2 screw, 24 patients) and C2‐TPS group (traditional C2 pedicle screw, 20 patients). The diameter of the maximum tangential circle, distance between geometric center and median sagittal plane and screw length of PPS and TPS were measured based on the 3D model of C2, respectively. Then the 3D printed navigation templated were designed and manufactured by 3D printing to assisted the PPS and TPS placement, respectively. The surgical time and radiation exposure times during operation were recorded; the post‐operative grading criteria, deviation of screw entry point and deviation of screw angle of two groups were evaluated, respectively. Results: A total of 48 screws were inserted in the C2‐PPS group, and 40 screws were inserted in the C2‐TPS group. There were 46 screws with grade 0 (95.8%) in the PPS group and 31 screws with grade 0 (77.5%) in the TPS group, (P = 0.03). The radiation exposure times in the C2‐PPS group and C2‐TPS group were 4.7 ± 1.5 and 7.8 ± 3.8, respectively, (P = 0.045). The deviations of screw entry point in the C2‐PPS group and C2‐TPS group were 1.2 ± 0.8 mm and 3.2 ± 1.3 mm, respectively; the deviations of screw angle in the C2‐PPS group and C2‐TPS group were 2.1 ± 1.6° and 4.8 ± 2.0°, respectively, (P = 0.000). The diameters of the maximum tangential circle in the C2‐PPS group and C2‐TPS group were 5.5 ± 1.0 mm and 5.3 ± 0.9 mm, respectively. The distances between the geometric center and median sagittal plane in the C2‐PPS group and C2‐TPS group were 15.4 ± 2.3 mm and 18.0 ± 3.3 mm, respectively; The screw lengths in the C2‐PPS group and C2‐TPS group were 25.9 ± 3.2 mm and 27.6 ± 3.7 mm, respectively, (P = 0.000). Conclusion: Eighty percent of C2‐PPS corridor can accommodate a 3.5 mm diameter screw, and with an average screw length of 26 mm. Navigation templates assisted the C2‐PPS placement is less surgical time, less radiation exposure times, more safe and more accurate than C2‐TPS. [ABSTRACT FROM AUTHOR]

Background: The status of the velopharyngeal mechanism can be inferred from perceptual ratings of specified speech parameters. Several studies have proposed the measure of an overall velopharyngeal composite score based on these perceptual ratings and have reported good validity. The Cleft Audit Protocol for Speech—Augmented (CAPS‐A) is a validated and reliable perceptual framework for the assessment of cleft speech and velopharyngeal function used by all Regional Cleft Services in the UK and Ireland. An overall velopharyngeal composite summary score based on the CAPS‐A would serve as an important surgical outcome measure of speech. Aims: To develop and validate a velopharyngeal composite summary score based on perceptual ratings made on the CAPS‐A (CAPS‐A VPC‐Sum) using data from a maxillary osteotomy (MO) study. Methods & Procedures: There were two surgical groups: a cleft lip and palate (CLP) (N = 20) group and a non‐CLP group (N = 10), and a normal control group (N = 20). Participants in groups 1 and 2 were seen for perceptual and instrumental assessments of speech and velopharyngeal function preoperatively (T1), 3 months (T2) and 12 months (T3) postoperatively. Perceptual speech data were collected and rated by independent listeners using CAPS‐A. Outcomes & Results: Moderate to strong interrater reliability for perceptual data (rs = 0.503–1.000, all p < 0.01) and strong to very strong reliability for videofluoroscopic measurements (rs = 0.746–0.947) were found. Construct validity of the CAPS‐A VPC‐Sum was shown by an increase in postoperative scores for the CLP group only ϰ2(2) = 9.769, p = 0.008 and significant differences between the CLP and the other two groups at T2 and T3 using independent t‐tests. Convergent and divergent validity was indicated by a positive moderate correlation with related parameters (e.g., hypernasality rs = 0.869, p < 0.01) and a weak correlation with unrelated parameters (e.g., amount of forward advancement rs = 0.160, p = 0.526). Criterion validity was found by a moderate correlation between closure ratio rs = –0.541, p = 0.020 and CAPS‐A VPC‐Sum. Conclusions & Implications: A velopharyngeal composite score based on perceptually rated parameters serves as an important surgical speech outcome measure. The CAPS‐A VPC‐Sum is a useful, reliable and valid outcome measure of velopharyngeal function. There are added positive implications for other clinicians using geographically and language‐specific adapted versions of the CAPS‐A internationally. What this paper adds: What is already known on this subject: Velopharyngeal composite scores based on perceptually rated speech parameters have been shown to have both clinical and research utility, serving as a useful surgical outcome measure. However, such a composite score must be specifically validated on the perceptual speech framework upon which it is based, as there are differences in measurement methods and terminology across cleft speech perceptual frameworks internationally. What this paper adds to existing knowledge: The CAPS‐A is a nationally used tool in the UK and Ireland for audit and research purposes with validated and adapted international versions. This paper reports on the validation of the derived velopharyngeal composite score measure based on the CAPS‐A and an English‐speaking sample, providing evidence of its validity through a speech osteotomy study. What are the potential or actual clinical implications of this work?: This work provides CLP teams who use CAPS‐A with a validated surgical speech outcome measure of velopharyngeal function. It has positive implications also for adapted versions of the CAPS‐A internationally. [ABSTRACT FROM AUTHOR]

Objective: For pelvic ring fractures, screw fixation became a popular technique for its good biomechanical performance. The safe insertion of anterograde the transpubic screw is important for patients with anterior pelvic ring fractures. This paper is to research the anatomical parameters of the anterograde transpubic screw corridor and evaluate the safety of anterograde transpubic screw placement assisted by the assembled navigation template. Methods: Fifty subjects with normal pelvic, 25 men and 25 women, age from 20 to 60 were enrolled, and their ilium were 3D reconstructed. The ilium was divided into zone I, zone II and zone III. Zone I and zone III was defined as medial and lateral to the obturator foramen, respectively. Zone II is located between zones I and III. The corridor A is formed by zone I and zone II and corridor B is formed by zone I, zone II and zone III. The diameter and length of the inner circle, the distance from the center of the inner circle to the posterior superior and to the inferior iliac spine of corridor A and corridor B were measured, respectively. Nine patients with pelvic fractures underwent anterograde transpubic screw and transverse sacroiliac screw placement assisted by the assembled navigation template and were retrospectively analyzed. Operation time, blood loss, incision length and fluoroscopy times were recorded. Grading score and Matta score were evaluated after surgery. Results: In the 50 subjects, the diameter of corridor A was 11.16 ± 2.13 mm, and that of corridor B was 8.54 ± 1.52 mm. The length of corridor A was 86.39 ± 9.35 mm, and that of corridor B was 117.05 ± 5.91 mm. The surface distance from the screw entry point to the posterior superior iliac spine in corridor A was 109.31 ± 11.06 mm, and that in corridor B was 127.86 ± 8.23 mm. The surface distance from the screw entry point to the posterior inferior iliac spine in corridor A was 91.16 ± 10.34 mm, and that in corridor B was 106.92 ± 7.91 mm. A total of 18 sacroiliac transverse screws and 11 anterograde transpubic screws were inserted assisted by assembled navigation templates for nine patients. The average operation time was 108.75 ± 25.71 min, the blood loss was 141.11 ± 50.21 ml, the incision length was 14 ± 4.62 cm, and the intraoperative fluoroscopy was 17.89 ± 4.01 times. Conclusion: Transpubic screw corridor can be obtained by 3D reconstruction. For the majority of patients, the anterograde pubic ramus corridor accommodated a 6.5 mm diameter screw. It is safe to use anterograde transpubic screw placement assisted by an assembled navigation template. [ABSTRACT FROM AUTHOR]

Background: Speech–language therapists (SLTs) seek a range of educational opportunities for training in adult videofluoroscopic swallow studies (VFSS). However, variable training methods and/or unequal access to training can influence VFSS practice. Aims: To document current SLT needs and barriers to VFSS training and to determine if a new beginner‐level VFSS eLearning program would assist to meet their training needs. The program incorporated multimedia modules on preparing, conducting, interpreting and reporting VFSS. Methods & Procedures: SLTs with limited experience in adult VFSS completed surveys relating to VFSS training experience and barriers, and perceived changes in knowledge, skills and confidence on core VFSS module topics pre‐ (n = 36) and post‐ (n = 32) eLearning training. Outcomes & Results: Inconsistent access to VFSS training opportunities and time‐related work pressures were reported as the greatest training barriers. SLTs viewed the eLearning program as a suitable option for VFSS training. Post‐training, participants perceived they gained confidence, as well as improved knowledge and skills in all VFSS aspects along with generalised benefits for dysphagia management. SLTs indicated that key benefits of the eLearning program were its comprehensive content and self‐directed learning with multimedia tools, which afforded theoretical and practical learning opportunities. Conclusions & Implications: The eLearning program offered SLTs free access to beginner‐level adult VFSS training, meeting many identified training needs and providing a foundation from which to develop further practical knowledge and skills within a VFSS clinic setting. What this paper addsWhat is already known on the subjectSLTs demonstrate variable knowledge and skill in conducting and interpreting VFSS, which can impact dysphagia diagnosis and management. While access to VFSS training can be challenging, the barriers to training for SLTs have not been clearly documented. Research has confirmed that eLearning can be used effectively in healthcare education, and in some aspects of VFSS training; however, it is yet to be applied to address the broad range of VFSS training needs.What this paper adds to existing knowledgeThis study describes the SLT reported barriers to VFSS training which include limited access to formal and practical training, workload‐related time pressures and the complexity of learning the VFSS skill set. The findings highlight that an eLearning program, was an accepted mode of learning for VFSS training. SLTs reported the online program met their learning needs by improving access to training, the multimedia program features supported their understanding of complex anatomical and physiological concepts, and training frameworks assisted their clinical reasoning and VFSS interpretation.What are the potential or actual clinical implications of this work?eLearning can assist in overcoming many VFSS training barriers identified by SLTs and the multimedia aspects of eLearning can effectively support VFSS beginner‐level education to complement and expedite in‐clinic practical training. Given that VFSS results inform decisions regarding commencement and progression of oral intake and swallow rehabilitation, enhanced VFSS training has the potential to positively influence dysphagia outcomes and quality of life. [ABSTRACT FROM AUTHOR]

Objective: To determine what importance is given to the puncture and assistive technologies in percutaneous nephrolithotomy (PNL) in the current urological literature. Methods: PubMed was searched for English publications and reviews for the keywords: 'percutaneous nephrolithotomy', 'percutaneous nephrostomy', 'puncture'. The search was limited to the last 5 years, January 2016 until February 2021. Based on 183 abstracts, 121 publications were selected, read, and reviewed. References, older or seminal papers were read and cited if they contributed to a better understanding. A total of 198 references form the basis of this narrative review. Results: The puncture is frequently referred to as the most crucial part of PNL. In contrast, the influence of the puncture on the failure rate of PNL and the specific puncture‐related complications seems to be low in the single‐digit percentage range. However, there are no universally accepted definitions and standards measuring the quality of puncture. Consequently, the impact of the puncture on general PNL complications, on stone scores predicting success rates and on learning curves evaluating surgeons' performance have not been systematically studied. Assistive technologies rely on fluoroscopy and ultrasonography, the latter of which is becoming the preferred imaging modality for monitoring the entire procedure. Needle bending, a problem relevant to all puncture techniques, is not addressed in the urological literature. Conclusions: The importance attached to puncture in PNL in the current urological literature is subjectively high but objectively low. Some basics of puncture are not well understood in urology. Disciplines other than urology are more actively involved in the development of puncture techniques. [ABSTRACT FROM AUTHOR]

ABSTRACT Direct anterior approach (DAA) with the patient lying supine has facilitated the use of intraoperative fluoroscopy and allows for standardized positioning of the patient. The current study presents a new technique to measure acetabular component anteversion using intraoperative fluoroscopy. The current paper describes a mathematical formula to calculate true acetabular component anteversion based on the acetabular component abduction angle and the c-arm tilt angle (CaT). The CaT is determined by tilting the c-arm until an external pelvic oblique radiograph with the equatorial plane of the acetabular component perpendicular to the fluoroscopy receptor is obtained. CaT is determined by direct reading on the C-arm device. The technique was validated using a radiopaque synbone model comparing the described technique to computed tomography anteversion measurement. The experiment was repeated 25 times. The difference in anteversion between the two measuring techniques was on average 0.2° (range −3.0-3.1). The linear regression coefficients evaluating the agreement between the experimental and control methods were 0.99 (95%CI 0.88-1.10, p < 0.001) and 0.33 (95%CI −1.53-2.20, p = 0.713) for the slope and intercept, respectively. The current study confirms that the described three-step c-arm acetabular cup measuring technique can reproducibly and reliably assess acetabular component anteversion in the supine position, as compared to CT-imaging. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2307-2312, 2017. [ABSTRACT FROM AUTHOR]

Purpose: This paper describes a novel method for simultaneous intrafraction tracking of multiple fiducial markers. Although the proposed method is generic and can be adopted for a number of applications including fluoroscopy based patient position monitoring and gated radiotherapy, the tracking results presented in this paper are specific to tracking fiducial markers in a sequence of cone beam CT projection images. Methods: The proposed method is accurate and robust thanks to utilizing the mean shift and random sampling principles, respectively. The performance of the proposed method was evaluated with qualitative and quantitative methods, using data from two pancreatic and one prostate cancer patients and a moving phantom. The ground truth, for quantitative evaluation, was calculated based on manual tracking preformed by three observers. Results: The average dispersion of marker position error calculated from the tracking results for pancreas data (six markers tracked over 640 frames, 3840 marker identifications) was 0.25 mm (at iscoenter), compared with an average dispersion for the manual ground truth estimated at 0.22 mm. For prostate data (three markers tracked over 366 frames, 1098 marker identifications), the average error was 0.34 mm. The estimated tracking error in the pancreas data was < 1 mm (2 pixels) in 97.6% of cases where nearby image clutter was detected and in 100.0% of cases with no nearby image clutter. Conclusions: The proposed method has accuracy comparable to that of manual tracking and, in combination with the proposed batch postprocessing, superior robustness. Marker tracking in cone beam CT (CBCT) projections is useful for a variety of purposes, such as providing data for assessment of intrafraction motion, target tracking during rotational treatment delivery, motion correction of CBCT, and phase sorting for 4D CBCT. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to provide a method and reference data for the evaluation of the weight dependence of the conversion coefficients from air collision kerma integrated over beam area to the effective dose for patients undergoing diagnostic x‐ray examinations. Method: A simple physics‐based analytical model was developed in order to calculate the weight dependence of the effective dose conversion coefficients based on existing values of the conversion coefficients between patient effective dose and air collision kerma integrated over beam area calculated by the Monte Carlo method on the base of computational MIRD‐5‐type stylized models. Results: The analytical expressions that make possible taking into account a patient's weight when assessing the effective dose were presented. The following categories of diagnostic x‐ray examinations are considered: CT; plain radiography; cardiac angiography; fluoroscopy. The results indicate that the weight dependence of the effective dose conversion coefficients for different categories of diagnostic x‐ray examinations has the same form. Correction factor for evaluation of the new value of the effective dose conversion coefficient for a patient with weight Wpa. when we know its value for a standard patient with weight Wst. depends on the ratios of their weights (Wst./Wpat.) and fractions of the incident energy which is imparted to a patient. Conclusions: The paper presents an approach and necessary data for the estimation of the weight dependence of the effective dose conversion coefficients for patients undergoing different diagnostic x‐ray examinations. [ABSTRACT FROM AUTHOR]

Introduction: The establishment of venous access is one of the driving factors for complications during implantation of pacemakers and defibrillators (cardiac implantable electronic devices [CIED]). Recently, a novel approach of accessing the cephalic vein for CIED by cephalic vein puncture (CVP) using a modified Seldinger technique has been described, promising high success rates and simplified handling with steeper learning curves. In this single‐center registry, we analyzed the safety and efficiency of CVP to SVP access after defining CVP as the primary access route in our center. Methods: A total of 229 consecutive patients receiving a CIED were included in the registry. Sixty‐one patients were implanted by primary or bail‐out SVP; 168 patients received primary cephalic preparation and CVP was performed when possible, using a hydrophilic transradial sheath. Results: Implantation of at least one lead via CVP was successful in 151 of 168 patients (90%), and implantation of all leads was possible in 122 of 168 patients (72.6%). Total implantation times and fluoroscopy times and doses did not differ between CVP and SVP implantations. Pneumothorax occurred in 0/122 patients implanted via CVP alone, but 8/107 (7.5%) patients received at least one lead via SVP. Conclusion: Our data confirms high success rates of the CVP for CIED implantation. Moreover, this method can be used without significantly prolonging the total procedure time or applying fluoroscopy dose compared to the highly efficient SVP while showing lower overall complication rates. [ABSTRACT FROM AUTHOR]

Purpose: To present the results of a patient dose evaluation program in pediatric cardiology and propose local diagnostic reference levels (DRLs) for different types of procedure and age range, in addition to suggesting approaches to correlate patient dose values with patient weight. This study was the first conducted in Latin America for pediatric interventional cardiology under the auspices of the International Atomic Energy Agency. Methods: Over three years, the following data regarding demographic and patient dose values were collected: age, gender, weight, height, number of cine series, total number of cine frames, fluoroscopy time (FT), and two dosimetric quantities, dose-area product (DAP) and cumulative dose (CD), at the patient entrance reference point. The third quartile values for FT, DAP, CD, number of cine series, and the DAP/body weight ratio were proposed as the set of quantities to use as local DRLs. Results: Five hundred and seventeen patients were divided into four age groups. Sample sizes by age group were 120 for <1 yr; 213 for 1 to <5 yr; 82 for 5 to <10 yr; and 102 for 10 to <16 yr. The third quartile values obtained for DAP by diagnostic and therapeutic procedures and age range were 1.17 and 1.11 Gy cm2 for <1 yr; 1.74 and 1.90 Gy cm2 for 1 to <5 yr; 2.83 and 3.22 Gy cm2 for 5 to <10 yr; and 7.34 and 8.68 Gy cm2 for 10 to <16 yr, respectively. The third quartile value obtained for the DAP/body weight ratio for the full sample of procedures was 0.17 (Gy cm2/kg) for diagnostic and therapeutic procedures. Conclusions: The data presented in this paper are an initial attempt at establishing local DRLs in pediatric interventional cardiology, from a large sample of procedures for the standard age bands used in Europe, complemented with the values of the ratio between DAP and patient weight. This permits a rough estimate of DRLs for different patient weights and the refining of these values for the age bands when there may be large differences in child size. These DRLs were obtained at the largest pediatric hospital in Chile, with an active optimization program, and could be used by other hospitals in the Latin America region to compare their current patient dose values and determine whether corrective action is appropriate. [ABSTRACT FROM AUTHOR]

Wavelength-dispersive high-resolution X-ray spectrometers often employ elastically bent crystals for the wavelength analysis. In a preceding paper [Honkanen et al. (2014). J. Synchrotron Rad. 21, 104-110] a theory for quantifying the internal stress of a macroscopically large spherically curved analyser crystal was presented. Here the theory is applied to compensate for the corresponding decrease of the energy resolution. The technique is demonstrated with a Johann-type spectrometer using a spherically bent Si(660) analyser in near-backscattering geometry, where an improvement in the energy resolution from 1.0 eV down to 0.5 eV at 9.7 keV incident photon energy was observed. [ABSTRACT FROM AUTHOR]

This paper provides a comprehensive overview of 3D transesophageal echocardiography still images and movies of mechanical mitral valves, mitral bioprostheses, and mitral valve repairs. Alongside these visual descriptions, the historical overview of surgical and percutaneous mitral valve intervention is described with the special emphasis on the incremental value of 3D transesophageal echocardiography (3DTEE). For each mitral valve intervention, 2D echocardiography, chest x-ray, and fluoroscopy images corresponding to 3 DTEE are given. In addition, key references on echocardiographic imaging of individual valves and procedures are enumerated in accompanying figures and tables. [ABSTRACT FROM AUTHOR]

Purpose: The efficiency of protective equipment for the brain has not been verified at the left anterior oblique (LAO) position, which is commonly used in clinical procedures. The purpose of this study was to investigate radiation exposure of the brain in interventional radiology (IR) and the shielding ability of a new protective flap. Methods: We made a flap that combined a protective cap with a left lateral face shield. The flap was made of tungsten‐containing rubber (TCR). An anthropomorphic head phantom was placed at the physician's position, and air kerma rates (μGy/min and μGy/15s) were measured by electronic dosimeter at three locations: the surface of the left side of the head, and the left and right temporal lobes with the protective cap and the flap in fluoroscopy and cine modes. The X‐ray tube was at the lower left side of the physician, and its angles were LAO60 and LAO60CAU40. The tube voltage (95–125 kV), tube current (4.7–732 mA), and air kerma rate (27.8–1078 mGy/min) were automatically adjusted by the X‐ray system. We obtained the cap and the flap shielding efficiencies. Results: In cine mode at LAO60CAU40, the shielding efficiencies on the surface of the left side of the head and left temporal lobe with the cap were 92.6% and 5.1%, respectively, and the corresponding shielding efficiencies with the flap were 92.5% and 86.1%, respectively. The flap can reduce radiation exposure of the brain more than the cap alone. Conclusions: At the left anterior oblique in interventional radiology, the flap can reduce exposure to the brain. [ABSTRACT FROM AUTHOR]

Purpose: To quantify operator dose in interventional CT fluoroscopy (CTF) procedures and compare to catheterization laboratory and interventional radiology procedures. Methods: Fifteen studies quantifying operator scatter dose for c‐arm fluoroscopy and CTF were reviewed from a literature survey. The dose provided in each study was normalized to skin entrance air kerma and air kerma rate including backscatter. The average air kerma rate and exposure duration were calculated and compared between c‐arm fluoroscopy and CTF. To enable operator scatter dose calculations in CTF procedures, a model was created which scaled the dose from a reference condition. Results: Our literature survey indicated that for CTF relative to c‐arm fluoroscopy: (1) the mean air kerma rate is 3.5 times higher, while (2) the mean exposure duration is 31.6 times lower. On average, a physician would have to perform 9.1 times (i.e., 31.6/3.5) more CTF procedures relative to c‐arm fluoroscopy procedure to receive equal operator scatter doses. Our own experimental measurements provided scaling factors allowing physician scatter dose to be obtained at any rotation time, tube current, beam collimation, or beam energy. Conclusion: Our results shed light onto a currently mis‐understood issue in radiology. Namely, that physicians receive more dose from CT relative to c‐arm fluoroscopy motivating them to retreat from the room during interventional exposures. Our literature review and experimental measurements indicate the opposite it true; interventional CT produces on average nine times less physician dose relative to c‐arm procedures. Our method allows for prospective/retrospective determination of an individual's dose. [ABSTRACT FROM AUTHOR]

Purpose: Recent research efforts investigating dose escalation techniques for three-dimensional conformal radiation therapy (3D CRT) and intensity modulated radiation therapy (IMRT) have demonstrated great benefit when high-dose hypofractionated treatment schemes are implemented. The use of these paradigms emphasizes the importance of smaller treatment margins to avoid high dose to surrounding normal tissue or organs at risk (OARs). However, tighter margins may lead to underdosage of the target due to the presence of organ motion. It is important to characterize organ motion and possibly account for it during treatment delivery. The need for real-time localization of dynamic targets has encouraged the use and development of more continuous motion monitoring systems such as kilo-voltage/fluoroscopic imaging, electromagnetic tracking, and optical monitoring systems. Methods: This paper presents the implementation of an algorithm to quantify translational and rotational interfractional and intrafractional prostate motion and compute the dosimetric effects of these motion patterns. The estimated delivered dose is compared with the static plan dose to evaluate the success of delivering the plan in the presence of prostate motion. The method is implemented on a commercial treatment planning system (Pinnacle3, Philips Radiation Oncology Systems, Philips Healthcare) and is termed delivered dose investigational tool (DiDIT). The DiDIT implementation in Pinnacle3 is validated by comparisons with previously published results. Finally, different workflows are discussed with respect to the potential use of this tool in clinical treatment planning. Results: The DiDIT dose estimation process took approximately 5-20 min (depending on the number of fractions analyzed) on a Pinnacle3 9.100 research version running on a Dell M90 system (Dell, Inc., Round Rock, TX, USA) equipped with an Intel Core 2 Duo processor (Intel Corporation, Santa Clara, CA, USA). The DiDIT implementation in Pinnacle3 was found to be in agreement with previously published results, on the basis of the percent dose difference (PDD). This metric was also utilized to compare plan dose versus delivered dose, for prostate targets in three clinically acceptable treatment plans. Conclusions: This paper presents results from the implementation of an algorithm on a commercially available treatment planning system that quantifies the dosimetric effects of interfractional and intrafractional motion in external beam radiation therapy (EBRT) of prostate cancer. The implementation of this algorithm within a commercial treatment planning system such as Pinnacle3 enables easy deployment in the existing clinical workflow. The results of the PDD tests validate the implementation of the DiDIT algorithm in Pinnacle3, in comparison with previously published results. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Dosimetric control of staff exposure during interventional procedures under fluoroscopy is of high relevance. In this paper, a novel ray casting approximation of radiation transport is presented and the potential and limitation vs. a full Monte Carlo transport and dose measurements are discussed. Method: The x‐ray source of a Siemens Axiom Artix C‐arm is modeled by a virtual source model using single Gaussian‐shaped source. A Geant4‐based Monte Carlo simulation determines the radiation transport from the source to compute scatter from the patient, the table, the ceiling and the floor. A phase space around these scatterers stores all photon information. Only those photons are traced that hit a surface of phantom that represents medical staff in the treatment room, no indirect scattering is considered; and a complete dose deposition on the surface is calculated. To evaluate the accuracy of the approximation, both experimental measurements using Thermoluminescent dosimeters (TLDs) and a Geant4‐based Monte Carlo simulation of dose depositing for different tube angulations of the C‐arm from cranial‐caudal angle 0° and from LAO (Left Anterior Oblique) 0°–90° are realized. Since the measurements were performed on both sides of the table, using the symmetry of the setup, RAO (Right Anterior Oblique) measurements were not necessary. Results: The Geant4‐Monte Carlo simulation agreed within 3% with the measured data, which is within the accuracy of measurement and simulation. The ray casting approximation has been compared to TLD measurements and the achieved percentage difference was −7% for data from tube angulations 45°–90° and −29% from tube angulations 0°–45° on the side of the x‐ray source, whereas on the opposite side of the x‐ray source, the difference was −83.8% and −75%, respectively. Ray casting approximation for only LAO 90° was compared to a Monte Carlo simulation, where the percentage differences were between 0.5–3% on the side of the x‐ray source where the highest dose usually detected was mainly from primary scattering (photons), whereas percentage differences between 2.8–20% are found on the side opposite to the x‐ray source, where the lowest doses were detected. Dose calculation time of our approach was 0.85 seconds. Conclusion: The proposed approach yields a fast scatter dose estimation where we could run the Monte Carlo simulation only once for each x‐ray tube angulation to get the Phase Space Files (PSF) for being used later by our ray casting approach to calculate the dose from only photons which will hit an movable elliptical cylinder shaped phantom and getting an output file for the positions of those hits to be used for visualizing the scatter dose propagation on the phantom surface. With dose calculation times of less than one second, we are saving much time compared to using a Monte Carlo simulation instead. With our approach, larger deviations occur only in regions with very low doses, whereas it provides a high precision in high‐dose regions. [ABSTRACT FROM AUTHOR]

Purpose: In the last decade, C-arm-based cone-beam CT became a widely used modality for intraoperative imaging. Typically a C-arm CT scan is performed using a circular or elliptical trajectory around a region of interest. Therefore, an angular range of at least 180° plus fan angle must be covered to ensure a completely sampled data set. However, mobile C-arms designed with a focus on classical 2D applications like fluoroscopy may be limited to a mechanical rotation range of less than 180° to improve handling and usability. The method proposed in this paper allows for the acquisition of a fully sampled data set with a system limited to a mechanical rotation range of at least 180° minus fan angle using a new trajectory design. This enables CT like 3D imaging with a wide range of C-arm devices which are mainly designed for 2D imaging. Methods: The proposed trajectory extends the mechanical rotation range of the C-arm system with two additional linear shifts. Due to the divergent character of the fan-beam geometry, these two shifts lead to an additional angular range of half of the fan angle. Combining one shift at the beginning of the scan followed by a rotation and a second shift, the resulting rotate-plus-shift trajectory enables the acquisition of a completely sampled data set using only 180° minus fan angle of rotation. The shifts can be performed using, e.g., the two orthogonal positioning axes of a fully motorized C-arm system. The trajectory was evaluated in phantom and cadaver examinations using two prototype C-arm systems. Results: The proposed trajectory leads to reconstructions without limited angle artifacts. Compared to the limited angle reconstructions of 180° minus fan angle, image quality increased dramatically. Details in the rotate-plus-shift reconstructions were clearly depicted, whereas they are dominated by artifacts in the limited angle scan. Conclusions: The method proposed here employs 3D imaging using C-arms with less than 180° rotation range adding full 3D functionality to a C-arm device retaining both handling comfort and the usability of 2D imaging. This method has a clear potential for clinical use especially to meet the increasing demand for an intraoperative 3D imaging. [ABSTRACT FROM AUTHOR]

Purpose: This paper reports the first results obtained using a novel technology called eye controlled region of interest (ECR) that substantially reduces both staff and patient irradiation during an interventional fluoroscopy procedure without interfering with workflow. Its collimator includes a partially x-ray attenuating plate with a nonattenuating aperture. An eye tracker follows the operator's gaze to automatically position the aperture to the clinical region of interest (CROI) anywhere in the image in real-time. Methods: Experiments were performed in a swine model using a mobile fluoroscope with a 30 cm image intensifier and manual control of fluoroscopic factors. The factory collimator and image display monitor were replaced with different components for this study. The full 30 cm field-of-view (FOV) of the image intensifier was irradiated at normal levels, and served as a baseline, when ECR was disengaged. With ECR engaged, most of the 30 cm FOV was irradiated to less than 20% of normal levels while the CROI was normally irradiated. Animal irradiation was determined by physical KAP (kerma area product) measurements. Operator irradiation was characterized by air kerma and air kerma rate measurements near the operator. Data were collected from three pairs of interventions in each of five swine models. Results: When ECR was engaged, KAP was reduced to 0.22 (p < 0.001) of baseline and operator irradiation to 0.27 (p < 0.001) of baseline. Overall procedure time had a borderline increase (p = 0.07) but fluoroscopy time was unchanged (p = 0.36) (Wilcoxon signed rank). Measured staff and patient radiation reductions are consistent with this collimator's design. Subjective impressions of imaging improvements are consistent with less scatter reaching the CROI. Engaging ECR reduced irradiation without subjectively or objectively increasing operator workload. Conclusions: The first in vivo evaluation of ECR demonstrated that this technology has objectively reduced KAP and operator irradiation by approximately 75% without interfering with the performance of fluoroscopically guided interventional procedures. In addition, reduced scatter production subjectively improved device visualization. These findings indicate the practicability of achieving better radiation optimization. [ABSTRACT FROM AUTHOR]

I To the Editor i : We appreciated the paper of Francica et al, entitled: Role of Contrast-Enhanced Ultrasound in the Detection of Complications After Ultrasound-Guided Liver Interventional Procedures.1 The authors clearly highlighted utility of contrast-enhanced ultrasound (CEUS) during and after percutaneous ultrasound-guided diagnostic and therapeutic liver procedures. Among the various subchapters of the article, we would like to focus and analyze the possible hemorrhagic vascular complications, in particular detecting by CEUS of intraparenchymal microbubble flow signal along the needle tract after liver biopsy. [Extracted from the article]

Purpose: X-ray fluoroscopy remains an important imaging modality in a number of image-guided procedures due to its real-time nature and excellent spatial detail. However, the radiation dose delivered raises concerns about its use particularly in lengthy treatment procedures (>0.5 h). The authors have previously presented an algorithm that employs feedback of geometric uncertainty to control dose while maintaining a desired targeting uncertainty during fluoroscopic tracking of fiducials. The method was tested using simulations of motion against controlled noise fields. In this paper, the authors embody the previously reported method in a physical prototype and present changes to the controller required to function in a practical setting. Methods: The metric for feedback used in this study is based on the trace of the covariance of the state of the system, tr(C). The state is defined here as the 2D location of a fiducial on a plane parallel to the detector. A relationship between this metric and the tube current is first developed empirically. This relationship is extended to create a manifold that incorporates a latent variable representing the estimated background attenuation. The manifold is then used within the controller to dynamically adjust the tube current and maintain a specified targeting uncertainty. To evaluate the performance of the proposed method, an acrylic sphere (1.6 mm in diameter) was tracked at tube currents ranging from 0.5 to 0.9 mA (0.033 s) at a fixed energy of 80 kVp. The images were acquired on a Varian Paxscan 4030A (2048 x 1536 pixels, ~100 cm source-to-axis distance, ~160 cm source-to-detector distance). The sphere was tracked using a particle filter under two background conditions: (1) uniform sheets of acrylic and (2) an acrylic wedge. The measured tr(C) was used in conjunction with a learned manifold to modulate the tube current in order to maintain a specified uncertainty as the sphere traversed regions of varying thickness corresponding to the acrylic sheets in the background. Results: With feedback engaged, the tracking error was found to correlate well with the specified targeting uncertainty. Tracking of the fiducial was found to be robust to changes in the attenuation presented by the varying background conditions. For a desired uncertainty of 5.0 mm, comparison of the feedback framework with a comparable system employing fixed exposure demonstrated dose savings of 29%. Conclusions: This work presents a relation between a state descriptor, tr(C), the x-ray tube current used, and an estimate of the background attenuation. This relation is leveraged to modulate the tube current in order to maintain a desired geometric uncertainty during fluoroscopy. The authors' work demonstrates the use of the method in a real x-ray fluoroscopy system with physical motion against varying backgrounds. The method offers potential savings in imaging dose to patients and staff while maintaining tracking uncertainty during fluoroscopy-guided treatment procedures [ABSTRACT FROM AUTHOR]

Keywords: interventional radiology; interventional radiologist; IRSA; CIRSE; IR EN interventional radiology interventional radiologist IRSA CIRSE IR 361 365 5 06/06/20 20200601 NES 200601 Background As specialists in the use of medical imaging, radiologists are in a unique position to offer a range of non-invasive and minimally invasive tests and procedures for patients. This is supported by the most recent Royal Australian and New Zealand College of Radiologists (RANZCR) workforce survey results from 2016.[1] Of the 2237 radiologists who responded, 155 identified as an interventional radiologist (IR) with the definition of Tier B procedures (advanced or complex) and 24 identified as an interventional neuroradiologist (INR). The conflict of interest statement is as follows: Dr Goh declares that he is current President of the Interventional Radiology Society of Australasia (IRSA) and a member of the Faculty of Clinical Radiology with the Royal Australian and New Zealand College of Radiologists (RANZCR). The authors wish to express that the opinion presented does not necessarily reflect the opinion of the committees on which Dr Goh, Dr Lukies, and Dr Clements reside. [Extracted from the article]

Background: Pelvic ring disruption (PRD) is a serious trauma associated with high mortality and disability rates. Poor reduction can lead to complications such as pelvic deformity and delayed fracture healing. Here, we introduce a new technology using mixed reality surgical navigation (MRSN) with an unlocking closed reduction technique (UCRT) frame to assist pelvic fracture reduction and fixation. Methods: Thirty patients with PRD were enrolled in this study. All of the patients underwent preoperative CT scans, with the pelvis and tracker segmented into three‐dimensional models. Under MRSN guidance, auxiliary reduction screws were inserted to grasp the pelvic bone. An ideal trajectory for closed reduction was planned, and suitable CS screws were used for stable fixation after good reduction. Operation time, fluoroscopy frequency, and both Matta and Majeed scores were analyzed. Results: The mean follow‐up period was 10.8 months (7.5, 12.25 months) (range 6–24 months). The average duration of operation was 212.5 min (187.5, 272.8 min) (range 133–562 min), and the average reduction time was 23.0 min (15.0, 42.5 min) (range 10–70). The average fluoroscopy frequency was 34.0 times (31.5, 52.5 times) (range 23–68 times). One hundred and fifty screws were successfully inserted on the first attempt. All the fractures healed well with no complications. Excellent reduction quality (Matta score ≤4 mm) was achieved in 29/30 cases, and good reduction quality (Matta score between 4 and 10 mm) was achieved in 1/30 cases. All patients achieved bone healing after an average of 4.0 months (3.5, 5.9 months) (range 3–6), as well as good function recovery with an average Majeed score of 91.0 (87.8, 95.0) (range 71–100). Conclusion: The MRSN technique described improved reduction accuracy and radiation exposure without considerable extension of operation time. [ABSTRACT FROM AUTHOR]

Objective: Improving accuracy and safety of pedicle screw placement is of great clinical importance. Electronic conductivity device (ECD) can be a promising technique with features of affordability, portability, and real‐time detection capabilities. This study aimed to validate the safety and effectiveness of a modified ECD. Methods: The ECD underwent a modification where six lamps of various colors, and it was utilized in a prospectively multicenter randomized controlled clinical trial involving 96 patients across three hospitals from June 2018 to December 2018. The trial incorporated a self‐control randomization with an equal distribution of left or right side of vertebral pedicle among two groups: the free‐hand group and the ECD group. A total of 496 pedicle screws were inserted, with 248 inserted in each group. The primary outcomes focused on the accuracy of pedicle screw placement and the frequency of intraoperative X‐rays. Meanwhile, the secondary indicator measured the time required for pedicle screw placement. Results were presented as means ± SD. Paired samples t‐test and χ2‐test were used for comparison. Furthermore, an updated review was conducted, which included studies published from 2006 onwards. Results: Baseline patient characteristics were recorded. The primary accuracy outcome revealed a 96.77% accuracy rate in the ECD group, compared to a 95.16% accuracy rate in the free‐hand group, with no significant differences noted. In contrast, ECD demonstrated a significant reduction in radiation exposure frequency when compared to the free‐hand group (1.11 ± 0.32 vs. 1.30 ± 0.53; p < 0.001), resulting in a 14.6% reduction. Moreover, ECD displayed a decrease of 30.38% in insertion time (70.88 ± 30.51 vs. 101.82 ± 54.00 s; p < 0.001). According to the results of the 21 studies, ECD has been utilized in various areas of the spine such as the atlas, thoracic and lumbar spine, as well as sacral 2‐alar‐iliac. The accuracy of ECD ranged from 85% to 100%. Conclusion: The prospectively randomized trial and the review indicate that the use of ECD presents a secure and precise approach to the placement of pedicle screws, with the added benefit of reducing both procedure time and radiation exposure. [ABSTRACT FROM AUTHOR]

Purpose: New technology has been developed to treat age-related macular degeneration (AMD) using 100 kVp pencil-beams that enter the patient through the radio-resistant sclera with a depth of interest between 1.6 and 2.6 cm. Measurement of reference and relative dose in a kilovoltage x-ray beam with a 0.42 cm diameter field size and a 15 cm source to axis distance (SAD) is a challenge that is not fully addressed in current guidelines to medical physicists. AAPMˈs TG-61 gives dosimetry recommendations for low and medium energy x-rays, but not all of them are feasible to follow for this modality. Methods: An investigation was conducted to select appropriate equipment for the application. PTWˈs Type 34013 Soft X-Ray Chamber (Freiburg, Germany) and CIRSˈs Plastic Water LR (Norfolk, VA) were found to be the best available options. Attenuation curves were measured with minimal scatter contribution and thus called Low Scatter Tissue Air Ratio (LSTAR). A scatter conversion coefficient (Cscat) was derived through Monte Carlo radiation transport simulation using MCNPX (LANL, Los Alamos, NM) to quantify the difference between a traditional TAR curve and the LSTAR curve. A material conversion coefficient (Cmat) was determined through experimentation to evaluate the difference in attenuation properties between water and Plastic Water LR. Validity of performing direct dosimetry measurements with a source to detector distance other than the treatment distance, and therefore a different field size due to a fixed collimator, was explored. A method-Integrated Tissue Air Ratio (ITAR)-has been developed that isolates each of the three main radiological effects (distance from source, attenuation, and scatter) during measurement, and integrates them to determine the dose rate to the macula during treatment. Results: LSTAR curves were determined to be field size independent within the range explored, indicating that direct dosimetry measurements may be performed with a source to detector distance of 20 cm even though the SAD is 15 cm during treatment. Cscat varied from 1.102 to 1.106 within the range of depths of interest. The experimental variance among repeated measurements of Cmat was larger than depth dependence, so Cmat was estimated as1.019 for all depths of interest. Conclusions: Equipment selection, measurement techniques, and formalism for the determination of dose rate to the macula during stereotaxy for AMD have been determined and are strongly recommended by the authors of this paper to be used by clinical medical physicists. [ABSTRACT FROM AUTHOR]

The 2012 Summer School of the American Association of Physicists in Medicine (AAPM) focused on optimization of the use of ionizing radiation in medical imaging. Day 2 of the Summer School was devoted to fluoroscopy and interventional radiology and featured seven lectures. These lectures have been distilled into a single review paper covering equipment specification and siting, equipment acceptance testing and quality control, fluoroscope configuration, radiation effects, dose estimation and measurement, and principles of flat panel computed tomography. This review focuses on modern fluoroscopic equipment and is comprised in large part of information not found in textbooks on the subject. While this review does discuss technical aspects of modern fluoroscopic equipment, it focuses mainly on the clinical use and support of such equipment, from initial installation through estimation of patient dose and management of radiation effects. This review will be of interest to those learning about fluoroscopy, to those wishing to update their knowledge of modern fluoroscopic equipment, to those wishing to deepen their knowledge of particular topics, such as flat panel computed tomography, and to those who support fluoroscopic equipment in the clinic. [ABSTRACT FROM AUTHOR]

Purpose: With the continuous development of new stent grafts and implantation techniques, it has now become technically feasible to treat abdominal aortic aneurysms (AAA) with challenging anatomy using endovascular repair with standard, fenestrated, or branched stent-grafts. In vitro experimentations are very useful to improve stent-graft design and conformability or imaging guidance for stent-graft delivery or follow-up. Vascular replicas also help to better understand the limitation of endovascular approaches in challenging anatomy and possibly improve surgical planning or training by practicing high risk clinical procedures in the laboratory to improve outcomes in the operating room. Most AAA phantoms available have a very basic anatomy, which is not representative of the clinical reality. This paper presents a method of fabrication of a realistic AAA phantom with a visible thrombus, as well as some mechanical properties characterizing such phantom. Methods: A realistic AAA geometry replica of a real patient anatomy taken from a multidetector computed tomography (CT) scan was manufactured. To demonstrate the multimodality imaging capability of this new phantom with a thrombus visible in magnetic resonance (MR) angiography, CT angiography (CTA), digital subtraction angiography (DSA), and ultrasound, image acquisitions with all these modalities were performed by using standard clinical protocols. Potential use of this phantom for stent deployment was also tested. A rheometer allowed defining hyperelastic and viscoelastic properties of phantom materials. Results: MR imaging measurements of SNR and CNR values on T1 and T2-weighted sequences and MR angiography indicated reasonable agreement with published values of AAA thrombus and abdominal components in vivo. X-ray absorption also lay within normal ranges of AAA patients and was representative of findings observed on CTA, fluoroscopy, and DSA. Ultrasound propagation speeds for developed materials were also in concordance with the literature for vascular and abdominal tissues. Conclusions: The mimicked abdominal tissues, AAA wall, and surrounding thrombus were developed to match imaging features of in vivo MR, CT, and ultrasound examinations. This phantom should be of value for image calibration, segmentation, and testing of endovascular devices for AAA endovascular repair. [ABSTRACT FROM AUTHOR]

Background: The Japanese Society of Emergency Pediatrics has formulated evidence-based guidelines for the management of intussusception in children in order to diagnose intussusceptions promptly, to initiate appropriate treatment as early as possible, and to protect intussuscepted children from death. Methods: Literature was collected systematically via the Internet using the key words 'intussusception' and 'children.' The evidence level of each paper was rated in accordance with the levels of evidence of the Oxford Center for Evidence-based Medicine. The guidelines consisted of 50 clinical questions and the answers. Grades of recommendation were added to the procedures recommended on the basis of the strength of evidence levels. Results: Three criteria of 'diagnostic criteria,''severity assessment criteria,' and 'criteria for patient transfer' were proposed aiming at an early diagnosis, selection of appropriate treatment, and patient transfer for referral to a tertiary hospital in severe cases. Barium is no longer recommended for enema reduction (recommendation D) because the patient becomes severely ill once perforation occurs. Use of other contrast media, such as water-soluble iodinated contrast, normal saline, or air, is recommended under either fluoroscopic or sonographic guidance. Delayed repeat enema improves reduction success rate, and is recommended if the initial enema partially reduced the intussusception and if the patient condition is stable. Conclusions: The guidelines offer standards of management, but it is not necessarily the purpose of the guidelines to regulate clinical practices. One should judge each individual clinical situation in accordance with experiences, available devices, and the patient's condition. [ABSTRACT FROM AUTHOR]

In a recently published paper, Nespolo & Benahsene [J. Appl. Cryst. (2021), 54, 1594–1599] state that 'chiral crystal structures from achiral molecules can occur in 28 types of space group having screw axes np, with p ≠ n/2, not in any Sohncke type of space group'. It is argued that chiral crystal structures from achiral molecules, in fact, occur in all 65 Sohncke space groups. [ABSTRACT FROM AUTHOR]

Purpose: In accurate proton spot-scanning therapy, continuous target tracking by fluoroscopic x ray during irradiation is beneficial not only for respiratory moving tumors of lung and liver but also for relatively stationary tumors of prostate. Implanted gold markers have been used with great effect for positioning the target volume by a fluoroscopy, especially for the cases of liver and prostate with the targets surrounded by water-equivalent tissues. However, recent studies have revealed that gold markers can cause a significant underdose in proton therapy. This paper focuses on prostate cancer and explores the possibility that multiple-field irradiation improves the underdose effect by markers on tumor-control probability (TCP). Methods: A Monte Carlo simulation was performed to evaluate the dose distortion effect. A spherical gold marker was placed at several characteristic points in a water phantom. The markers were with two different diameters of 2 and 1.5 mm, both visible on fluoroscopy. Three beam arrangements of single-field uniform dose (SFUD) were examined: one lateral field, two opposite lateral fields, and three fields (two opposite lateral fields + anterior field). The relative biological effectiveness (RBE) was set to 1.1 and a dose of 74 Gy (RBE) was delivered to the target of a typical prostate size in 37 fractions. The ratios of TCP to that without the marker (TCPr) were compared with the parameters of the marker sizes, number of fields, and marker positions. To take into account the dependence of biological parameters in TCP model, α/β values of 1.5, 3, and 10 Gy (RBE) were considered. Results: It was found that the marker of 1.5 mm diameter does not affect the TCPs with all α/β values when two or more fields are used. On the other hand, if the marker diameter is 2 mm, more than two irradiation fields are required to suppress the decrease in TCP from TCPr by less than 3%. This is especially true when multiple (two or three) markers are used for alignment of a patient. Conclusions: It is recommended that 1.5-mm markers be used to avoid the reduction of TCP as well as to spare the surrounding critical organs, as long as the markers are visible on x-ray fluoroscopy. When 2-mm markers are implanted, more than two fields should be used and the markers should not be placed close to the distal edge of any of the beams. [ABSTRACT FROM AUTHOR]

The role of imaging and image guidance is increasing in surgery and therapy, including treatment planning and follow-up. Fluoroscopy is used for two-dimensional (2D) guidance or localization; however, many procedures would benefit from three-dimensional (3D) guidance or localization. Three-dimensional computed tomography (CT) using a C-arm mounted x-ray image intensifier (XRII) can provide high-quality 3D images; however, patient dose and the required acquisition time restrict the number of 3D images that can be obtained. C-arm based 3D CT is therefore limited in applications for x-ray based image guidance or dynamic evaluations. 2D-3D model-based registration, using a single-plane 2D digital radiographic system, does allow for rapid 3D localization. It is our goal to investigate—over a clinically practical range—the impact of x-ray exposure on the resulting range of 3D localization precision. In this paper it is assumed that the tracked instrument incorporates a rigidly attached 3D object with a known configuration of markers. A 2D image is obtained by a digital fluoroscopic x-ray system and corrected for XRII distortions (±0.035 mm) and mechanical C-arm shift (±0.080 mm). A least-square projection-Procrustes analysis is then used to calculate the 3D position using the measured 2D marker locations. The effect of x-ray exposure on the precision of 2D marker localization and on 3D object localization was investigated using numerical simulations and x-ray experiments. The results show a nearly linear relationship between 2D marker localization precision and the 3D localization precision. However, a significant amplification of error, nonuniformly distributed among the three major axes, occurs, and that is demonstrated. To obtain a 3D localization error of less than ±1.0 mm for an object with 20 mm marker spacing, the 2D localization precision must be better than ±0.07 mm. This requirement was met for all investigated nominal x-ray exposures at 28 cm FOV, and for all but the lowest two at 40 cm FOV. However, even for those two nominal exposures, the expected 3D localization error is less than ±1.2 mm. The tracking precision was ±0.65 mm for the out-of-plane translations, ±0.05 mm for in-plane translations, and ±0.05° for the rotations. The root mean square (RMS) difference between the true and projection-Procrustes calculated location was 1.07 mm. It is believed these results show the potential of this technique for dynamic evaluations or real-time image guidance using a single x-ray source and XRII detector. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging, bi-plane X-ray fluoroscopy and biomechanical modelling are enabling technologies for the non-invasive evaluation of muscle, ligament and joint function during dynamic activity. This paper reviews these various technologies in the context of their application to the study of human movement. We describe how three-dimensional, subject-specific computer models of the muscles, ligaments, cartilage and bones can be developed from high-resolution magnetic resonance images; how X-ray fluoroscopy can be used to measure the relative movements of the bones at a joint in three dimensions with submillimetre accuracy; how complex 3-D dynamic simulations of movement can be performed using new computational methods based on non-linear control theory; and how musculoskeletal forces derived from such simulations can be used as inputs to elaborate finite-element models of a joint to calculate contact stress distributions on a subject-specific basis. A hierarchical modelling approach is highlighted that links rigid-body models of limb segments with detailed finite-element models of the joints. A framework is proposed that integrates subject-specific musculoskeletal computer models with highly accurate in vivo experimental data. [ABSTRACT FROM AUTHOR]

Background: Vascular diseases are often treated minimally invasively. The interventional material (stents, guidewires, etc.) used during such percutaneous interventions are visualized by some form of image guidance. Today, this image guidance is usually provided by 2D X‐ray fluoroscopy, that is, a live 2D image. 3D X‐ray fluoroscopy, that is, a live 3D image, could accelerate existing and enable new interventions. However, existing algorithms for the 3D reconstruction of interventional material require either too many X‐ray projections and therefore dose, or are only capable of reconstructing single, curvilinear structures. Purpose: Using only two new X‐ray projections per 3D reconstruction, we aim to reconstruct more complex arrangements of interventional material than was previously possible. Methods: This is achieved by improving a previously presented deep learning‐based reconstruction pipeline, which assumes that the X‐ray images are acquired by a continuously rotating biplane system, in two ways: (a) separation of the reconstruction of different object types, (b) motion compensation using spatial transformer networks. Results: Our pipeline achieves submillimeter accuracy on measured data of a stent and two guidewires inside an anthropomorphic phantom with respiratory motion. In an ablation study, we find that the aforementioned algorithmic changes improve our two figures of merit by 75 % (1.76 mm → 0.44 mm) and 59 % (1.15 mm → 0.47 mm) respectively. A comparison of our measured dose area product (DAP) rate to DAP rates of 2D fluoroscopy indicates a roughly similar dose burden. Conclusions: This dose efficiency combined with the ability to reconstruct complex arrangements of interventional material makes the presented algorithm a promising candidate to enable 3D fluoroscopy. [ABSTRACT FROM AUTHOR]

Kinematics of total knee replacements (TKR) play an important role in assessing the success of a procedure and would be a valuable addition to clinical practice; however, measuring TKR kinematics is time consuming and labour intensive. Recently, an automatic single‐plane fluoroscopic method utilizing machine learning has been developed to facilitate a quick and simple process for measuring TKR kinematics. This study aimed to validate the new automatic single‐plane technique using biplanar radiostereometric analysis (RSA) as the gold standard. Twenty‐four knees were imaged at various angles of flexion in a dedicated RSA lab and 113 image pairs were obtained. Only the lateral RSA images were used for the automatic single‐plane technique to simulate single‐plane fluoroscopy. Two networks helped automate the kinematics measurement process, one segmented implant components and the other generated an initial pose estimate for the optimization algorithm. Kinematics obtained via the automatic single plane and manual biplane techniques were compared using root‐mean‐square error and Bland–Altman plots. Two observers measured the kinematics using the automated technique and results were compared with assess reproducibility. Root‐mean‐square errors were 0.8 mm for anterior–posterior translation, 0.5 mm for superior–inferior translation, 2.6 mm for medial–lateral translation, 1.0° for flexion–extension, 1.2° for abduction–adduction, and 1.7° for internal–external rotation. Reproducibility, reported as root‐mean‐square errors between operator measurements, was submillimeter for in‐plane translations and below 2° for all rotations. Clinical Significance: The advantages of the automated single plane technique should aid in the kinematic measurement process and help researchers and clinicians perform TKR kinematic analyses. [ABSTRACT FROM AUTHOR]

The article discusses a paper by R. C. Pimentel and colleagues on whether intracardiac echocardiography (ICE) can reduce the complications of atrial fibrillation ablation. Topics mentioned the advantages and disadvantages of ICE, the consequences of the inability of ICE to visualize thrombus and the aortic root, and the association of ICE use with rates of in-hospital mortality and length of stay.

Objective: Accurately inserting pedicle screws is the key point of posterior pedicle screw fixation for lower cervical spine (C3–C7) instability. 3D printing technology can improve the accuracy of screw placement. This study compared the safety of 3D‐printed flexible drill guiding template vs. traditional rigid drill guiding template for lower cervical pedicle screw insertion. Methods: This was a retrospective study. A total of 34 patients who underwent lower cervical pedicle screw fixation from March 2018 to May 2021 were enrolled in this study, and they were divided into the flexible drill flexible drill group and the traditional drill group. A total of 18 patients in the flexible drill flexible drill group underwent pedicle screw fixation assisted by 3D printed flexible drill guiding templates for the lower cervix, and 16 patients in the traditional drill group underwent pedicle screw fixation assisted by 3D printed regular drill guiding templates for the lower cervix. The length of the incision and intraoperative blood loss during surgery were recorded and compared for the two groups. The grade, deviation of the screw entry point, deviation of the screw medial angle and screw length were measured and compared after surgery for the two groups by independent‐sample tests. Results: There was a significant difference in the length of the incision and blood loss between the two groups (P < 0.05). There was a significant difference between the two groups for grade (P = 0.016). The deviation of the screw entry point was 0.65 ± 0.50 mm in the flexible drill group and 0.78 ± 0.83 mm in the traditional drill group. The deviation of the screw medial angle was 2.14 ± 1.78 in the flexible drill group and 4.23 ± 2.51 in the traditional drill group, with a significant difference between the two groups (P < 0.05). Conclusion: Compared with regular guiding techniques, lower cervical pedicle screw placement assisted by multistep navigation templates and flexible K‐wires results in less trauma and better safety. [ABSTRACT FROM AUTHOR]

Background: Catheter ablation (CA) remains challenging due to suboptimal success rates in persistent atrial fibrillation (AF). Existing mapping technologies cannot reliably distinguish sources in this patient population. Recently, the novel electrographic flow (EGF) mapping system was developed using a modified Horn‐Schunk optical flow algorithm to detect and quantify patterns of electrical wavefront propagation in the atria. Objectives: To test the hypothesis that targeted source ablation based on EGF mapping is superior to empiric AF ablation. Methods: We included all consecutive patients undergoing EGF guided ablation for persistent AF. All patients underwent pulmonary vein isolation (PVI) and were treated with the same EAM system (CARTO). The outcome of PVI+EGF guided CA was compared with data of PVI‐only procedures (PVI‐only group) and PVI plus additional empiric adjunctive linear and substrate ablations (PVI+LINES group). 12‐months outcome as freedom from AF and atrial tachycardia/flutter (AT/AFL), procedural safety and efficiency characterized by procedure duration, fluoroscopy use, radiofrequency applications and duration, were analyzed. Both intention‐to‐treat and per protocol analysis were conducted. Results: A total number of 70 patients (39 in PVI+EGF, 16 in PVI‐only and 15 patients in PVI+LINES group) were enrolled. Intention‐to‐treat analysis showed fewer AF recurrences in PVI+EGF as compared with the PVI‐only or PVI+LINES groups at 12 months (25.6% vs. 62.5% vs. 53.3%, p =.02). There were no differences in AT/AFL recurrence (17.9% vs. 37.5% vs. 20.0%, p =.37). Procedure times were longer in PVI+EGF group (p <.01), and there were no differences in fluoroscopy use (p =.67). Conclusion: Our data suggest that patients treated with EGF‐guided CA developed fewer AF recurrences. Although the procedure times are longer, it seems to be safe and offers a more targeted, patient‐specific ablation strategy beyond PVI than adjunctive empiric lines and substrate ablation in this complex group of patients. [ABSTRACT FROM AUTHOR]

Background: In 2021, a 7.2 magnitude earthquake struck Haiti resulting in a surge of orthopaedic trauma requiring immediate surgical treatment. Safe and efficient operative management of orthopaedic trauma injuries requires intraoperative fluoroscopy through C-arm machines. The Haitian Health Network (HHN) received a philanthropic donation of three C-arm machines and considered an analytical tool may guide efficacious placement of those machines. The study objective was to develop and apply a clinical needs and hospital readiness measuring tool relevant to C-arm machines, which may guide decision-makers, such as HHN, in response to an emergency situation with a surge in need for orthopaedic treatment. Methods: An online survey to assess surgical volume and capacity was created and then completed by a senior surgeon or hospital administrator based at hospitals within the HHN. Multiple-choice and free-text answer data were collected and classified into five categories: staff, space, stuff, systems, and surgical capacity. Each hospital received a final score out of 100, calculated by equal weighting of each category. Results: Ten out of twelve hospitals completed the survey. The average weighted score for the staff category was 10.2 (SD 5.12), the space category was 13.1 (SD 4.09), the stuff category was 15.6 (SD 2.56), the systems category was 12.25 (SD 6.50), and the surgical capacity category was 9.5 (SD 6.47). The average final hospital scores ranged from 29.5 to 83.0. Conclusion: This analysis tool provided data as to the clinical demand and capabilities of hospitals within the HHN to receive a C-arm machine and reaffirmed the critical need for more C-arms in Haiti. This methodology may be utilised by other health systems to provide data to distribute orthopaedic trauma equipment, which would benefit communities during periods of surge capacity, such as natural disasters. [ABSTRACT FROM AUTHOR]

Background: It is unclear if the location of implantation of the leadless pacemaker (LP) makes a difference in the incidence of pacing‐induced cardiomyopathy (PICM). Aim: The aim of this study was to compare the incidence of PICM based on the location of implantation of LP. Methods: A total of 358 consecutive patients [women: 171 (48%), mean age: 73 ± 15 years] with left ventricular ejection fraction (EF) > 50%, who received an LP (Micra) between January 2017 and June 2022, formed the study cohort. Micra‐AV and Micra‐VR were implanted in 122 (34%) and 236 (66%) patients, respectively. Fluoroscopically, the location of implantation of LP in the interventricular septum (IS) was divided into two equal halves (apex/apical septum [AS] and mid/high septum [HS]). During follow‐up, PICM was defined as an EF drop of ≥10%. Results: LP was implanted in 109 (34%) and 249 (66%) patients at AS and HS locations, respectively. During a mean 18 ± 8 months follow‐up, 28 patients (7.8%) developed PICM. Among the 249 patients with HS placement of LP, 10 (4%) developed PICM, whereas among the 109 patients with AS placement of LP, 18 (16.5%) developed PICM (p =.002). AS location was associated with a higher risk of PICM compared to HS locations (adjusted hazard ratio: 4.42, p <.001). Conclusion: AS location of LP was associated with a higher risk of PICM compared to HS placement. Larger randomized studies are needed to confirm our findings. [ABSTRACT FROM AUTHOR]

Objective: Fluoroscopy is often used in the surgery of unstable pelvic ring fractures, and improved safety in implant placement is an issue. An anterior subcutaneous pelvic fixator (INFIX) combined with a percutaneous screw has been reported to be a minimally invasive and effective surgical technique for unstable pelvic ring injuries. However, although percutaneous screw fixation is minimally invasive, its indications for fracture fixation and fractures with large fragment displacements in the vertical plane remain controversial. Therefore, this technical note aims to describe a new technique for unstable pelvic ring fractures. Methods: We describe a 360° fusion of the pelvic ring to treat unstable pelvic ring fractures, including vertical shear pelvic ring fractures, using an intraoperative CT navigation system. Seven patients were treated with 360° fusion for type C pelvic ring fractures. In surgery, after reducing the fracture with external fixation, intraoperative CT navigation is used to perform a 360° fusion with INFIX and minimally invasive surgical spinopelvic fixation (MIS‐SPF). We will introduce a typical case and explain the procedure. Results: A 360° fixation was performed, and no perioperative complications were noted. The mean blood loss was 253.2 ± 141.0 mL, and the mean operative time was 224.3 ± 67.4 min. In a typical case, bone union was obtained 1 year after surgery, and we removed all implants. Conclusions: MIS‐SPF has a strong fixation force and helps reduce fractures' horizontal and vertical planes. In addition, 360° fusion with intraoperative CT navigation may help treat unstable pelvic ring fractures. [ABSTRACT FROM AUTHOR]

Dysfunction of upper pharyngoesophageal region in systemic sclerosis ( SSc) is infrequent, poorly recognised and poorly documented in the literature. Yet, it can have very distressing and even fatal consequences that may yet be very responsive to appropriate management. This paper documents the findings and outcome of management of a series of five patients with SSc who had pharyngoesophageal dysphagia to demonstrate the above. Following the documentation of a patient with SSc that had severe pharyngoesophageal dysphagia in 1981, this paper reports the findings in five patients with SSc presenting thereafter, having the same manifestations. Patients 1-4 who had barium swallow and fluoroscopy, demonstrated pharyngoesophageal dysfunction as basis of their symptoms. Patient 1 had fatal outcome from pulmonary haemorrhage following repeated bouts of aspiration pneumonia. Patients 2 and 3 had a long history of SSc and were on appropriate medical treatment. They developed a short history of dysphagia that resolved with additional improvements in swallowing techniques. Patient 4 had a short history of scleroderma, but severe and very distressing dysphagia that failed to respond to improved swallowing techniques alone, but responded well to the addition of medical treatment for SSc, over a 14-24 months period. Patient 5 had a short history of SSc and dysphagia that responded well to medical treatment over 6-12months. We conclude that pharyngoesophageal dysphagia in SSc, is a rare, very distressing and potentially fatal manifestation that can have a very favourable outcome with appropriate management. [ABSTRACT FROM AUTHOR]

The percutaneous bioavailability of naproxen is low and several technologies have been utilized to overcome the problem. Although, some studies have reported the permeation‐enhancing properties of natural essential oils, no research has reflected the effectiveness of Lavandula angustifolia essential oil (LAEO) on increasing the percutaneous absorption of naproxen sodium from a topical gel. Therefore, the present study was designed to investigate whether LAEO increased the percutaneous absorption and the analgesic effects of naproxen sodium topical gel. In the present study, naproxen topical gel was formulated using carbopol 940 (a gelling agent) and several vehicles such as PEG 400, ethanol, and water and the properties of gels were measured. Percutaneous absorption‐enhancing properties of LAEO were measured too. Based on our data, the essential oil‐containing formulation of naproxen represented greater penetration into (222.19 ± 24.87 vs. 107.65 ± 6.38 μg/cm2), and also across (22.07 ± 4.42 vs. 13.14 ± 2.87 μg/cm2) skin layers compared to the naproxen gel. Additionally, a significant analgesic property was observed in the naproxen topical gel containing 0.5% essential oil during both first and late phases of formalin test, as well as the late phase of tail‐flick test. It could be concluded that LAEO significantly enhanced naproxen percutaneous absorption and also its analgesic effects. [ABSTRACT FROM AUTHOR]

Introduction: Unidirectional block, left atrium to pulmonary vein (LA‐PV) entrance block without PV‐LA exit block, has not been fully investigated in the setting of ablation index (AI)‐guided pulmonary vein (PV) isolation (PVI). The aim of this study was to investigate unidirectional blocks during AI‐guided PVI. Methods: After achieving entrance block, exit block was evaluated by pacing from the catheter placed in the PV. Local PV musculature capture without conduction to the LA was necessary to prove exit block. Results: In total, 441 PVs (including nine left common PVs) from 113 consecutive patients (mean age: 71 ± 12 years, 77 men, 61 paroxysmal atrial fibrillation cases) who underwent initial AI‐guided PVI for atrial fibrillation were studied. Entrance block was achieved in all PVs. of the 247/441 (56%) PVs showing local PV musculature capture, 5/247 (2.0%) showed unidirectional blocks. Three of the five PVs (left superior and inferior PVs in one patient; right superior PV in another patient) showed LA‐PV reconnection, requiring additional ablation to achieve bidirectional block during the procedure. Two of the five PVs (left superior and inferior PVs in one patient) showed LA‐PV reconnection, and thereafter, LA‐PV conduction became blocked again spontaneously, leading to bidirectional block without further ablation during the procedure. Conclusion: AI‐guided PVI presented a low prevalence of unidirectional block (2%), using entrance block alone as the endpoint of PVI could therefore be justified. [ABSTRACT FROM AUTHOR]

Radiation dose to patients undergoing cardiac imaging procedures in cardiac catheterisation laboratories (cath labs) can be relatively high, so implementing strategies to reduce dose is important. Lowering the fluoroscopy pulse rate is a simple, yet effective method to reduce radiation dose. Sensible, iterative changes made in this area have the potential for significant patient and staff radiation dose reduction. [ABSTRACT FROM AUTHOR]