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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.

Although image-guided interventional procedures of the elbow and wrist are routinely performed, there is poor evidence in the literature concerning such treatments. Our aim was to perform a Delphi-based consensus on published evidence on image-guided interventional procedures around the elbow and wrist and provide clinical indications on this topic.A board of 45 experts in image-guided interventional musculoskeletal procedures from the European Society of Musculoskeletal Radiology were involved in this Delphi-based consensus study. All panelists reviewed and scored published papers on image-guided interventional procedures around the elbow and wrist updated to September 2018 according to the Oxford Centre for Evidence-based Medicine levels of evidence. Consensus on statements drafted by the panelists about clinical indications was considered as "strong" when more than 95% of panelists agreed and as "broad" if more than 80% agreed.Eighteen statements were drafted, 12 about tendon procedures and 6 about intra-articular procedures. Only statement #15 reached the highest level of evidence (ultrasound-guided steroid wrist injections result in greater pain reduction and greater likelihood of attaining clinically important improvement). Seventeen statements received strong consensus (94%), while one received broad consensus (6%).There is still poor evidence in published papers on image-guided interventional procedures around the elbow and wrist. A strong consensus has been achieved in 17/18 (94%) statements provided by the panel on clinical indications. Large prospective randomized trials are needed to better define the role of these procedures in clinical practice.• The panel provided 18 evidence-based statements on clinical indications of image-guided interventional procedures around the elbow and wrist. • Only statement #15 reached the highest level of evidence: ultrasound-guided steroid wrist injections result in greater pain reduction and greater likelihood of attaining clinically important improvement. • Seventeen statements received strong consensus (94%), while broad consensus was obtained by 1 statement (6%).

Learning objectives Background Findings and procedure details Conclusion Personal information References, Learning objectives: We want to explain the technique with Stentriever and what is the material used to achieve the thrombectomy with it. Additionally, we will explain the importance and the technique of the stentrievers in the stroke treatment, showing some cases of...

The need for mapping skin doses during fluoroscopically-guided X-ray procedures has been described by a number of institutions and experts. Different large photographic or X-ray films placed on the patient's skin have been found to be useful for recording doses up to 1.0-2.0 Gy - depending on the film - and up to 15 Gy using radiochromic films. Though the upper limit of the film sensitivity is seldom exceeded during interventional procedures, the main disadvantage of the X-ray films is still the excessive sensitivity for long, high dose procedures. Radiochromic films show poor definition for doses below 0.5 Gy and are expensive. The goal of the present paper is to analyse the possibilities of using common resin-coated photographic paper for this purpose. Sensitometric curves obtained with different paper types processed in conventional X-ray film automatic processors demonstrate that some of them can be used with better results than X-ray films at a very low cost. Doses from about 10 mGy to near 3.0 Gy can be measured with good accuracy using a variety of glossy photographic papers.

ALARA represents a practice mandate adhering to the principle of keeping radiation doses to patients and personnel As Low As Reasonably Achievable. This concept is strongly endorsed by the Society for Pediatric Radiology, particularly in the use of procedures and modalities involving higher radiation doses such as CT and fluoroscopic examinations of pediatric patients. There is no doubt that medical imaging, which has undergone tremendous technological advances in recent decades, is integral to patient care. However, these technological advances generally precede the knowledge of end-users concerning the optimal use and correct operation of the resulting imaging equipment, and such knowledge is essential to minimizing potential risks to the patients. Current imaging methods must be optimized for radiation dose reduction in pediatric patients who might be as much as ten times more radiosensitive than adults. Unlike straightforward radiographic examinations, radiation dose to the patient during fluoroscopy is dependent on the operator’s training, experience with the fluoroscope, and efficiency in completing a diagnostic study. The range of pediatric radiation doses from fluoroscopy is wide because this examination is performed not only by pediatric radiologists but also by general radiologists who occasionally care for children, interventional cardiologists, gastroenterologists, urologists and others. Thus, a venue where multidisciplinary interaction by this variety of operators can occur serves to improve pediatric patient care. The third ALARA conference organized by the Society for Pediatric Radiology was held in Orlando, Fla., on 11–2 February 2006. It was co-sponsored by the Office of Rare Diseases and the National Cancer Institute of the National Institutes of Health (NCI/NIH). The conference was funded by unrestricted educational grants from three manufacturers of fluoroscopic and interventional equipment (GE, Philips, Siemens) and financial support from the Society for Pediatric Radiology and NCI/NIH. The 22 faculty members consisted of 8 pediatric radiologists, 5 medical physicists, 3 pediatric subspecialists, 3 industry speakers, and 3 radiation epidemiology researchers. A diverse cadre of 74 pediatric radiologists, medical physicists, radiologic technologists, researchers, pediatric subspecialists and vendors met to examine the risk of radiation exposure from fluoroscopic and interventional procedures, identify means by which to reduce ionizing radiation exposure, and explore future technologic modifications that could optimize imaging while further reducing radiation exposures.

Aims and objectives Methods and materials Results Conclusion Personal information References, Aims and objectives: Lead has been used for radiation protection in clinical settings for many years; however it is toxic 1,2 , and can cause symptoms of poisoning including stomach ache, vomiting, extensor paralysis and dysesthesia following exposure to the skin or...

2Division of Diagnostic Imaging, St. Jude Children’s Research Hospital, 332 N Lauderdale St., Mailstop 752, Memphis, TN 38105-2794. Address correspondence to S. C. Kaste (sue.kaste@stjude.org). LARA represents a practice mandate adhering to the principle of keeping radiation doses of patients and personnel As Low As Reasonably Achievable. This concept is strongly endorsed by the Society for Pediatric Radiology, particularly in the use of procedures and modalities of higher radiation doses such as CT and fluoroscopic examinations of pediatric patients. There is no doubt that medical imaging, which has undergone tremendous technological advances in recent decades, is integral to patient care. However, these technological advances might precede the knowledge of end-users with respect to optimal use of such equipment and the correct operation of imaging equipment so that potential risks to the patient are minimized. Current imaging methods must be optimized for radiation dose reduction of pediatric patients who might be as much as 10 times more radiosensitive than adults. Unlike straightforward radiographic examinations, patient radiation dose during fluoroscopy is dependent on the operator’s training, experience with the fluoroscope, and efficiency in completing a diagnostic study. The range of pediatric radiation doses from fluoroscopy is wide because this examination is performed not only by pediatric radiologists but by general radiologists who occasionally care for children, interventional cardiologists, gastroenterologists, urologists, and others. Thus, a venue where multidisciplinary interaction by this variety of operators can occur serves to improve pediatric patient care. The third ALARA conference organized by the Society for Pediatric Radiology was held in Orlando, Fla., on Feb. 11–12, 2006. It was cosponsored by the Office of Rare Diseases and the National Cancer Institute of the National Institutes of Health (NCI/National Institutes of Health (NIH)). The conference was funded by unrestricted educational grants from three manufacturers of fluoroscopic and interventional equipment (GE, Philips, Siemens) and financial support from the Society for Pediatric Radiology and NCI/NIH. The 22 faculty members consisted of 8 pediatric radiologists, 5 medical physicists, 3 pediatric subspecialists, 3 industry speakers, and 3 radiation epidemiology researchers. A diverse cadre of 74 pediatric radiologists, medical physicists, radiologic technologists, researchers, pediatric subspecialists and vendors met to examine the risk of radiation exposure from fluoroscopic and interventional procedures, identify means by which to reduce ionizing radiation exposure, and explore future technologic modifications that could optimize imaging while further reducing radiation exposures.

Surgeons are always searching for useful methods that enhance surgical accuracy. In the case of endoscopic plantar fasciotomy, identifying the optimal location for insertion of the endoscope for precise sectioning of the desired portion of the plantar fascia, without increasing the risk of injury to adjacent anatomic structures and without complicating the surgery in terms of time or costs, would be beneficial to patients and surgeons alike. In the present techniques report, a simple method for accurately determining the optimal location for placement of the endoscope for execution of plantar fasciotomy is described.

Knee arthroplasty implants are designed with features that provide varying articular constraint over the range of flexion such that the pattern of knee motion may also vary. Because the motions of total knee implants have a direct influence on patient function and device longevity, it is important to understand how knee implants based on a variety of design philosophies perform in vivo. Fifty-nine knees in patients with 5 designs of implants were studied with fluoroscopic imaging during gait and stair-climbing activities. Many knees showed significantly different kinematics between the gait and stair activities, as well as differences from knees having other implant designs. The measured motions were consistent with the intrinsic constraint provided by the implant components and the variation in constraint over the flexion range.

A summation analysis of more than 70 individual kinematic studies involving normal knees and 33 different designs of total knee arthroplasty (TKA) was done with the objective of analyzing implant design variables that affect knee kinematics. Eight hundred eleven knees (733 subjects) were analyzed either during the stance phase of gait or a deep knee bend maneuver while under fluoroscopic surveillance. Fluoroscopic videotapes then were downloaded onto a workstation computer and anteroposterior (AP) femorotibial translational patterns were determined using an automated three-dimensional model fitting technique. The highest magnitude of translation was found in the normal and ACL-retaining TKA groups. Paradoxical anterior femoral translation during deep flexion was most commonly observed in PCL-retaining TKA. Substantial variability in kinematic patterns was observed in all groups. The least variability during gait was observed in mobile-bearing TKA designs, whereas posterior-stabilized TKA designs (fixed or mobile-bearing) showed the least variability during a deep knee bend. A medial pivot kinematic pattern was observed in only 55% of knees during deep knee flexion. Kinematic patterns of fixed versus mobile-bearing designs were similar with the exception of mobile-bearing TKA during gait in which femorotibial contact remained relatively stationary with minimal AP femorotibial translation.

An added filter on the collimator of the X-ray tube is useful for reducing exposure dose in interventional radiology (IVR). During IVR, high-quality fluoroscopic images are needed around the target region, but the portion of the fluoroscopic image that shows catheter/guide wires need not to be of high quality. Thus, we constructed an additional filter (spot filter) consisting of a copper sheet with an open hole in the center. The spot filter is moved by a remote control technique and can be used in cases of neurological, cardiac, abdominal, and pelvic IVR. Using this filter, image quality was improved at the target region of the image intensifier, because scatter radiation was attenuated in the periphery. Although image quality was deteriorated in the periphery, there was no significant disadvantage for IVR. The spot filter would be effective in reducing exposure dose in cases where the image quality of the target region needs to be maintained and in prolonged fluoroscopy.

Respiratory function data are useful for the evaluation of lung disease. To develop a new method of computer analysis for screening chest radiography that would provide respiratory kinetics automatically, we quantified and analyzed the movement of pulmonary markings and the changes in lung density during respiration. In this study, we obtained fluoroscopic chest images of a healthy volunteer during respiration using an image intensifier (I. I.) fluoroscopy system. We analyzed the vector of the movement of pulmonary markings and measured the regional mean density of sequential chest images during respiration. The movement of pulmonary markings in the upper lung field was less than that in the lower lung field. Variation in the phase density curve of the upper lung field was less than that of the lower lung field. Our results indicate that changes in density were regular and were synchronized with respiration. This computerized method may aid radiologists in the evaluation of lung diseases such as chronic obstructive pulmonary disease (COPD) , where abnormal respiratory change in density occurs as a result of air trapping.

The reduction of hip fractures prior to using dynamic hip screw devices can be challenging. The use of folded paper recreates an optimal angle of 135 degrees to assess adequacy of hip fracture reduction and to alert the surgeon as to the precise entry point of the guidewire in the lateral cortex of the femur.

Biliary ductal anomalies of surgical importance can occur in 10% of patients. The short cystic duct draining into the common bile or right hepatic duct and the extreme proximity of the common bile duct in case of spiral or posterior entry of the cystic duct--if not recognized in time--can result in ductal injuries. The new mobile, digitized fluoroscopic units provide a vastly improved image within minutes. In case of an inadvertent ductal injury (extravasation, no contrast material visible in the proximal ductal system) the surgeon can immediately repair the injury. Routine intraoperative cholangiography is strongly recommended during laparoscopic cholecystectomies.

Pediatric patients might be as much as 10 times more radiosensitive than adults. Thus, adherence to the principle of "As low as reasonably achievable" (ALARA) represents a practice mandate that minimizes ionizing radiation exposure while optimizing imaging results. This symposium is the third multidisciplinary program that focused on the ALARA principle in pediatric imaging and addressed issues associated with pediatric fluoroscopy and interventional imaging techniques.

Objective: To compare the outcome of nerve root injection guided by ultrasound/MRI fusion with radiofrequency needle tracking (eTRAX©) and the same procedure undertaken by fluoroscopic guidance. Methods: This is a retrospective audit of anonymised clinical records from before and after a change in the imaging technique used to perform nerve root blocks. We studied 181 consecutive patients who had undergone a nerve root block, the first 124 guided by fluoroscopic technique and the next 57 guided by ultrasound/MRI fusion with radiofrequency needle guidance. Using pain diaries, we reviewed the outcome scores at 24 h and 2 weeks. We recorded the use of analgesia, the patient’s satisfaction, complications and the duration of the procedures. Results: Completed pain diaries were returned by 61% in the fluoroscopy group and 67% in the fusion imaging group. The visual analogue pain score was reduced at 24 h by 3.29 [standard deviation (SD) 2.35] for the fluoroscopy group and by 3.69 (SD 2.58) in the fusion group (p 0.399). At two weeks the pain reduction was 3.27 (SD 2.57) for the fluoroscopic group and 4.21 (SD 2.95) for the fusion group (p 0.083). There was no statistically significant difference between the groups. The patient’s satisfaction scores were similar for both groups. The procedure by the two guidance methods took a similar time to perform. There were no serious complications in either group. One patient in the fusion-guided nerve root block group experienced paraesthesia in the nerve distribution for 2 h. Conclusion: Ultrasound/MRI fusion imaging with needle tracking is an effective alternative to fluoroscopic image-guided injection. Advances in knowledge: Fusion imaging guidance provides the same outcome as fluoroscopic guidance. Fusion imaging guidance avoids the need for ionising radiation.

Background The aim of this cadaver study was to evaluate an original technique for measuring posterior tibial translation based on an angle value instead of a distance value, with and without posterior stress application. It was hypothesized that an angle measurement of the posterior tibial translation would confirm the presence of a PCL tear with the knee flexed and completely extended. Method Using fresh cadavers, a set of strict lateral views were taken by fluoroscopy with the knee at 0°, 45° and 90° flexion on the intact knee and after transecting the PCL. The primary endpoint was the change in the posterior translation measured using a new technique, the ABC angle. This measurement was compared to the conventional posterior translation distance measurement with and without a posterior stress placed on the knee. Results Application of a posterior stress revealed clear changes in posterior translation after PCL transection with the knee at 0° for the angle technique and at 45° and 90° for the two techniques (p Conclusion Our technique provides a reliable radiographic measurement of posterior translation with the knee in extension, which should make it easier to acquire radiographs in patients who have pain with knee flexion. This angular measurement also has the advantage of not needing length calibration contrary to the reference technique. Level of evidence IV

This paper summarizes the dose to the eye lens of workers of Memorial Sloan Kettering Cancer Center, a high-volume US oncologic and associated diseases facility. The doses presented in this report were collected from personal dosemeter readings using optically stimulated luminescence badges to estimate Hp(3). Doses were collected for 5950 clinical and research workers between January 2012 and December 2017. The median eye lens dose for all monitored workers was 0.23 mSv y−1. Workers performing, or supporting, fluoroscopy procedures received the highest unprotected eye lens dose of all workers with a median eye dose of 10 mSv. The use of leaded glasses by this group reduced the actual doses to the lens. Nurses and technicians involved in positron emission tomography injections received median eye lens dose of 1.2 mSv.

Background A small aortic annulus is associated with increased risk of prosthesis–patient mismatch (PPM) after transcatheter aortic valve implantation (TAVI). Whether specific transcatheter heart valve (THV) designs yield superior hemodynamic performance in these small anatomies remains unclear. Methods Data from 8411 consecutive patients treated with TAVI from May 2012 to April 2019 at four German centers were retrospectively evaluated. A small aortic annulus was defined as multidetector computed tomography-derived annulus area 2. TAVI was performed with a balloon-expanding intra-annular (Sapien-3, n = 288), self-expanding intra-annular (Portico, n = 110), self-expanding supra-annular (Evolut, n = 179 and Acurate-Neo, n = 428) and mechanically expanding infra-annular (Lotus, n = 64) THV according to local practice. PPM was defined as indexed effective orifice area ≤ 0.85cm2/m2. Results A small annulus was found in 1069 (12.7%) patients. PPM was detected in 38.3% overall with a higher prevalence after implantation of a balloon-expanding intra-annular or mechanically expanding infra-annular THV compared to self-expanding intra- and supra-annular THV. Multivariable analysis linked self-expanding THV (Evolut: Odds ratio [OR] 0.341, Acurate-Neo: OR 0.436, Portico: OR 0.291), postdilatation (OR 0.648) and age (OR 0.968) to lower rates of PPM, while aortic valve calcification was associated with an increased risk (OR 1.001). Paravalvular regurgitation > mild was more frequent after TAVI with self-expanding THV (p = 0.04). Conclusion In this large contemporary multicenter patient population, a substantial number of patients with a small aortic anatomy were left with PPM after TAVI. Self-expanding supra- and intra-annular THV demonstrated superior hemodynamics in these patients at risk, however at the cost of higher rates of residual paravalvular regurgitation. Graphic abstract

Background Heyde syndrome (HS) is known as the association of severe aortic stenosis (AS) and recurrent gastrointestinal bleeding (GIB) from angiodysplasia. Data on the prevalence of HS and results after TAVI remain scarce. Methods 2548 consecutive patients who underwent TAVI for the treatment of AS from 2008 to 2017 were evaluated for a history of GIB and the presence of HS. The diagnosis of HS was defined as a clinical triad of severe AS, a history of recurrent GIB, and an endoscopic diagnosis of angiodysplasia. These patients (Heyde) were followed to investigate clinical outcomes, bleeding complications and the recurrence of GIB and were compared to patients with GIB unrelated to HS (Non-Heyde). Results A history of GIB prior to TAVI was detected in 190 patients (7.5%). Among them, 47 patients were diagnosed with HS (1.8%). Heyde patients required blood transfusions more frequently compared to Non-Heyde patients during index hospitalization (50.0% vs. 31.9%, p = 0.03). Recurrent GIB was detected in 39.8% of Heyde compared to 21.2% of Non-Heyde patients one year after TAVI (p = 0.03). In patients diagnosed with HS and recurrent GIB after TAVI, the rate of residual ≥ mild paravalvular leakage (PVL) was higher compared to those without recurrent bleeding (73.3% vs. 38.1%, p = 0.05). Conclusion A relevant number of patients undergoing TAVI were diagnosed with HS. Recurrent GIB was detected in a significant number of Heyde patients during follow-up. A possible association with residual PVL requires further investigation to improve treatment options and outcomes in patients with HS. Graphic abstract

Cone beam computed tomography (CBCT) provides multiplanar cross-sectional imaging and three-dimensional reconstructions and can be used intraoperatively in a hybrid operating room. In this study, we investigated the feasibility of using a CBCT-scanner for detecting residual stones during percutaneous nephrolithotomy (PCNL). Intraoperative CBCT-scans were made during PCNL procedures from November 2018 until March 2019 in a university hospital. At the point where the urologist would have otherwise ended the procedure, a CBCT-scan was made to image any residual fragments that could not be detected by either nephroscopy or conventional C-arm fluoroscopy. Residual fragments that were visualized on the CBCT-scan were attempted to be extracted additionally. To evaluate the effect of this additional extraction, each CBCT-scan was compared with a regular follow-up CT-scan that was made 4 weeks postoperatively. A total of 19 procedures were analyzed in this study. The mean duration of performing the CBCT-scan, including preparation and interpretation, was 8 min. Additional stone extraction, if applicable, had a mean duration of 11 min. The mean effective dose per CBCT-scan was 7.25 mSv. Additional extraction of residual fragments as imaged on the CBCT-scan occurred in nine procedures (47%). Of the follow-up CT-scans, 63% showed a stone-free status as compared to 47% of the intraoperative CBCT-scans. We conclude that the use of CBCT for the detection of residual stones in PCNL is meaningful, safe, and feasible.

Introduction The development of interventional cardiology increases the number of invasive procedures which are inevitably associated with increased exposure to ionizing radiation and associated risks. A percutaneous coronary intervention (PCI) substantiated by evaluation of the coronary artery lesion’s functional significance is recommended by both European and American cardiologists. Nevertheless, the prevalence of physiology-guided PCIs does not exceed 10% all over the globe. Aim To identify the physiology evaluation method which is associated with the lowest exposure to ionising radiation. Material and methods Anonymised data of 421 patients with stable angina pectoris for whom elective coronary artery angiography followed by physiological assessment of intermediate coronary artery stenosis was performed were prospectively included in this study. Only diagnostic-procedure-related data of dose of ionizing radiation were analysed. Physiological assessment of coronary artery lesions was performed by fractional flow reserve (FFR), quantitative flow ratio (QFR), or instantaneous wave-free ratio (iFR). Results Compared to FFR as a reference, fluoroscopy time (FT) was almost half in QFR and almost double in iFR, p < 0.001. QFR was associated with more than 3 times shorter FT compared to iFR. The dose area product was 663.87 ±260.51 cGy/cm2 (p = 0.03) lower in QFR compared to iFR. Conclusions QFR is associated with significantly reduced exposure to ionising radiation compared to both FFR and iFR. Therefore, wider QFR application in clinical practice could eliminate any additional exposure to ionising radiation and increase the prevalence of physiology-guided coronary artery revascularization.

Institutional imaging protocols for the verification of brachytherapy applicator placements were investigated in a survey study of domestic radiotherapy institutions. The survey form designed by a free on-line survey system was distributed via the mailing-list system of the Japanese Society for Radiation Oncology. Survey data of 75 institutions between August 2019 and October 2019 were collected. The imaging modalities used were dependent on resources available to the institutions. The displacement of a brachytherapy applicator results in significant dosimetric impact. It is essential to verify applicator placements using imaging modalities before treatment. Various imaging modalities used in institutions included a computed tomography (CT) scanner, an angiography X-ray system, a multi-purpose X-ray system and a radiotherapy simulator. The median total exposure time in overall treatment sessions was \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} }{}$\le$\end{document}75 s for gynecological and prostate cancers. Some institutions used fluoroscopy to monitor the brachytherapy source movement. Institutional countermeasures for reducing unwanted imaging dose included minimizing the image area, changing the imaging orientation, reducing the imaging frequency and optimizing the imaging conditions. It is worth noting that half of the institutions did not confirm imaging dose regularly. This study reported on the usage of imaging modalities for brachytherapy in Japan. More caution should be applied with interstitial brachytherapy with many catheters that can lead to potentially substantial increments in imaging doses for monitoring the actual brachytherapy source using fluoroscopy. It is necessary to share imaging techniques, standardize imaging protocols and quality assurance/quality control among institutions, and imaging dose guidelines for optimization of imaging doses delivered in radiotherapy should be developed.

Objectives: Constantly increasing number of procedures performed – endovascular or hybrid in patients with aortoiliac occlusive disease during the last decades finds its explanation in the lower morbidity and mortality rates, compared to bypass surgery. The purpose of the current survey was to estimate patients’ radiation exposure in aortoiliac segment after endovascular or hybrid revascularization and to study the main factors which have direct contribution. Methods: A retrospective study of 285 procedures conducted with the help of a mobile C-arm system in 223 patients was performed. Procedures were grouped according to criteria such as: type of intervention, vascular access, level of complexity and operating team. Different analyses were performed within the groups and dose values. Results: The median values of kerma–air product (KAP), the number of series and the peak skin dose (PSD) significantly increase with the increasing number of vascular accesses: for one access (16.68 Gy.cm2, 6 and 336 mGy), for two (56.93 Gy.cm2, 11 and 545 mGy), and for three (102.28 Gy.cm2, 15 and 781 mGy). Significant dependence was observed in the case of single access site between the type of access and the dose values: hybrid and retrograde common femoral artery/superficial femoral artery (CFA/SFA) endovascular accesses, 10.06 Gy.cm2/301 mGy and 13.23 Gy.cm2/318 mGy respectively, in contrast with the contralateral CFA and left brachial access, 33 Gy.cm2/421 mGy and 38.33 Gy.cm2/448 mGy respectively. Conclusion: The results demonstrate that the most important factors increasing the dose values are number and type of vascular accesses, followed by the combination and number of implanted stents with the complexity of the procedure. The PSD values for a single procedure were between 2 and 12 times lower than those IAEA proposed as trigger levels for radiation-induced erythema. This study shows that trigger levels were not reached even for patients with repeated procedures in the same segment in 1-year period. Advances in knowledge: The study gives important understanding and clarity on the growing awareness for dose-modifying factors during endovascular and hybrid revascularization of aortoiliac segment.

This paper describes a study to estimate absorbed doses to various organs from film-based chest radiographs and their uncertainties in the periods 1930 to 1948, 1949 to 1955, and 1956 to 1969. Estimated organ doses will be used in new analyses of risks of cancer and other diseases in tuberculosis patients in Canada who had chest fluoroscopic and radiographic examinations in those periods. In this paper, doses to lungs, female breast, active bone marrow, and heart from a single chest radiograph in adults and children of ages 1, 5, 10, and 15 y in the Canadian cohort and their uncertainties are estimated using (1) data on the tube voltage (kV), total filtration (mm Al), tube-current exposure-time product (mA s), and tube output (mR [mA s]−1) in each period; (2) assumptions about patient orientation, distance from the source to the skin of a patient, and film size; and (3) new calculations of sex- and age-specific organ dose conversion coefficients (organ doses per dose in air at skin entrance). Variations in estimated doses to each organ across the three periods are less than 20% in adults and up to about 30% at younger ages. Uncertainties in estimated organ doses are about a factor of 2 to 3 in adults and up to a factor of 4 at younger ages and are due mainly to uncertainties in the tube voltage and tube-current exposure-time product.

The purpose of this study was to assess the positional repeatability of internal and external markers among multiple breath-hold (BH) sessions and evaluate the positional variation of these markers within BH sessions for volumetric-modulated arc therapy (VMAT) for pancreatic cancer patients. A total of 13 consecutive pancreatic cancer patients with an internal marker were enrolled. Single full-arc coplanar VMAT was delivered under end-exhalation BH conditions while monitoring the internal marker with kilovoltage (kV) X-ray fluoroscopy. Positional repeatability of the internal and external markers was determined by the difference between the reference and zero position in all BH sessions, and positional variation was defined by the displacement from the reference position in each BH session during megavolt beam delivery. The overall positional repeatability was 0.6 ± 1.5 mm in the X-axis for the centroid of the internal marker (CoIM), −0.1 ± 2.2 mm in the Y-axis for the CoIM, and 0.8 ± 2.2 mm for the external marker. The frequency of an internal marker position appearing > 2 mm from the reference position in the Y-axis, despite the external marker position being ≤2 mm from the reference position, ranged from 0.0 to 39.9% for each patient. Meanwhile, the proportion of sessions with positional variation ≤2 mm was 93.2 and 98.7% for the CoIM and external marker, respectively. External marker motion can be used as a surrogate for pancreatic tumor motion during BH-VMAT delivery; however, margins of ~5 mm were required to ensure positional repeatability.

Although the clinical value of fluoroscopically guided respiratory endoscopy (bronchoscopy) is clear, there have been very few studies on the radiation dose received by staff during fluoroscopically guided bronchoscopy. The International Commission on Radiological Protection (ICRP) is suggesting reducing the occupational lens dose limit markedly from 150 to 20 mSv/year, averaged over defined periods of five years. The purpose of this study was to clarify the current occupational eye dose of bronchoscopy staff conducting fluoroscopically guided procedures. We measured the occupational eye doses (3-mm-dose equivalent, Hp(3)) of bronchoscopy staff (physicians and nurses) over a 6-month period. The eye doses of eight physicians and three nurses were recorded using a direct eye dosimeter, the DOSIRIS. We also estimated eye doses using personal dosimeters worn at the neck. The mean ± SD radiation eye doses (DOSIRIS) to physicians and nurses were 7.68 ± 5.27 and 2.41 ± 1.94 mSv/6 months, respectively. The new lens dose limit, 20 mSv/year, may be exceeded among bronchoscopy staff, especially physicians. The eye dose of bronchoscopy staff (both physicians and nurses) was underestimated when measured using a neck dosimeter. Hence, the occupational eye dose of bronchoscopy staff should be monitored. To reduce the occupational eye dose, we recommend that staff performing fluoroscopically guided bronchoscopy wear Pb glasses. correct evaluation of the lens dose [Hp(3)] using an eye dosimeter such as the DOSIRIS is necessary for bronchoscopy staff.