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A 69-year-old man presented at 10 weeks postimplantation with a 31-mm Watchman FLX migrating into the left atrium. Due to incomplete left atrial appendage seal and embolization risk, transcatheter device extraction was performed without complications. Herein we describe the technique and procedural steps, using cardiac computed tomography and benchtop models to guide practice.

Hirschsprung's disease is defined by the absence of the enteric nervous system (ENS) from the distal bowel. Primary treatment is "pull-through" surgery to remove bowel that lacks ENS, with reanastomosis of "normal" bowel near the anal verge. Problems after pull-through are common, and some may be due to retained hypoganglionic bowel (ie, low ENS density). Testing this hypothesis has been difficult because counting enteric neurons in tissue sections is unreliable, even for experts. Tissue clearing and 3-dimensional imaging provide better data about ENS structure than sectioning. Regions from 11 human colons and 1 ileal specimen resected during Hirschsprung's disease pull-through surgery were cleared, stained with antibodies to visualize the ENS, and imaged by confocal microscopy. Control distal colon from people with no known bowel problems were similarly cleared, stained, and imaged. Quantitative analyses of human colon, ranging from 3 days to 60 years old, suggest age-dependent changes in the myenteric plexus area, ENS ganglion area, percentage of myenteric plexus occupied by ganglia, neurons/mm2, and neuron Feret's diameter. Neuron counting using 3-dimensional images was highly reproducible. High ENS density in neonatal colon allowed reliable neuron counts using 500-μm2 × 500-μm2 regions (36-fold smaller than in adults). Hirschsprung's samples varied 8-fold in proximal margin enteric neuron density and had diverse ENS architecture in resected bowel. Tissue clearing and 3-dimensional imaging provide more reliable information about ENS structure than tissue sections. ENS structure changes during childhood. Three-dimensional ENS anatomy may provide new insight into human bowel motility disorders, including Hirschsprung's disease. [Display omitted] The enteric nervous system controls most bowel functions, and when defective or missing, serious disease ensues. By making bowel translucent, the enteric nervous system becomes visible. This new strategy could improve outcomes. [ABSTRACT FROM AUTHOR]

Background: Swelling and edema of the hand and forearm may occur in various traumatic and degenerative diseases. So far, no precise measurement protocol exists. The objective of this study was to evaluate an examination protocol with relevant regions of interest (ROIs) measured by a 3-dimensional (3D) scanner to achieve precise, reproducible, and objective measurements for an optimized detection of volumes of the hand and forearm. Methods: A 3D scan protocol was developed using an Artec, 3D scanner EVA to measure discrete hand volumes of healthy volunteers. Five areas were defined as ROIs, representing volumes of the finger, metacarpus, wrist, hand, and distal forearm. Contralateral limbs were used for volume comparisons and calculation of volume differences. Results: For this study, 12 individuals (58.3% women, 24 hands and forearms) with a mean age of 27.1 ± 3 years were included. Mean volume values for left and right ROIs correlated with each other, with slightly higher volumes for the right upper extremity. Volume differences showed statistically significant results for the finger region (ROI I; P =.009), the metacarpal region (ROI II; P <.001), hand region (ROI IV; P =.001), and forearm region (ROI V; P =.006), with the exception of the wrist region (ROI III; P =.722). Conclusions: Our results demonstrate that this 3D volumetric approach is a reliable and objective tool for measuring volumes and circumferences in hand and forearm. Based on our determined ROIs, further studies are needed to explore the significance for clinical applications. [ABSTRACT FROM AUTHOR]

Cardiac Computed Tomography (CCT) has become a reliable imaging modality in cardiology providing robust information on the morphology and structure of the heart with high temporal and isotropic spatial resolution. For the past decade, there has been a paradigm shift in the management of valvular heart disease since previously unfavorable candidates for surgery are now provided with less-invasive interventions. Transcatheter heart valve interventions provide a real alternative to medical and surgical management and are often the only treatment option for valvular heart disease patients. Successful transcatheter valve interventions rely on comprehensive multimodality imaging assessment. CCT is the mainstay imaging technique for preprocedural planning of these interventions. CCT is critical in guiding patient selection, choice of procedural access, device selection, procedural guidance, as well as allowing postprocedural follow-up of complications. This article aims to review the current evidence of the role of CCT in the preprocedural planning of patients undergoing transcatheter valvular interventions. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the use of computed tomography (CT) with automatic rib unfolding and three-dimensional (3D) volume-rendered imaging in the detection and characterization of rib fractures and flail chest. A total of 130 patients with blunt chest trauma underwent whole-body CT, and five independent readers assessed the presence and characterization of rib fractures using traditional CT images, automatic rib unfolding, and 3D volume-rendered images in separate readout sessions at least 2 weeks apart. A gold standard was established by consensus among the readers based on the combined analysis of conventional and reformatted images. Automatic rib unfolding significantly reduced mean reading time by 47.5%–74.9% (P < 0.0001) while maintaining a comparable diagnostic performance for rib fractures (positive predictive value [PPV] of 82.1%–93.5%, negative predictive value [NPV] of 96.8%–98.2%, and 69.4%–94.2% and 96.9%–99.1% for conventional axial images and 70.4%–85.1% and 95.2%–96.6% for 3D images) and better interobserver agreement (kappa of 0.74–0.87). For flail chest, automatic rib unfolding showed a PPV of 85.7%–100%, NPV of 90.4%–99.0%, and 80.0%–100% and 89.7%–100% for conventional axial images and 76.9%–100% and 89.0%–92.1% for 3D images. Automatic rib unfolding demonstrated equivalent diagnostic performance to conventional images in detecting acute rib fractures and flail chest, with good interobserver agreement and time-saving benefits. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study is to compare three-dimensional cephalometric measurements of the skeleton and dentoalveolar region between Turkish individuals and individuals from other populations. Methods: This is a single-center, retrospective study using cone beam computed tomography images (CBCT). Individuals have no missing teeth, are between the ages of 18 and 30, have a balanced profile, and have an Angle Class I relationship. The CBCT images were obtained in DICOM format and analyzed in DOLPHIN 11.8 software. 61 parameters were measured on the CBCT images, and 14 parameters were contrasted with individuals from other populations. Results: Mandibular values were more protrusive in Korean and Chinese populations than in Turkish and Cypriot individuals. Similarly, upper facial height (N- ANS distance) was found to be much higher. It was found that the length of the mandibular corpus was shorter and the angle of convexity was higher in Turks and Cypriots than in Koreans and Chinese populations. Conclusion: Ethnic facial and skeletal characteristics play a fundamental role in the outcome and course of orthodontic treatment. Gender differences also play an important role when facial sizes and proportions are compared in different societies. [ABSTRACT FROM AUTHOR]

Background and purpose: Zirconia abutments have been widely adopted in clinical implant practice. The unique mechanical properties of zirconia may significantly affect the long‐term prognosis of implant treatments. The purpose of this study was to investigate the influence of abutment material on implant deformation and fracture resistance of internal conical connection implant–abutment complexes of two diameters after standardized artificial aging. Materials and methods: Thirty original abutments (one‐piece titanium, one‐piece zirconia, zirconia with alloy base) with two diameters (regular, narrow) were connected to internal conical connection implants and subjected to a standardized artificial aging process consisting of thermal cycling and mechanical cyclic loading. Microcomputed tomography (μCT) scans of implant bodies were performed before and after aging. 3‐dimensional images of implant bodies were generated from the μCT scans and aligned for before and after aging to calculate the volumetric deformation amount. Finally, fracture resistance was measured using a mechanical static loading test for the surviving aged and 30 brand‐new specimens. Results: All specimens survived artificial aging. No significant difference in implant deformation was found in the regular groups (p = 0.095). In narrow groups, the one‐piece zirconia group showed significantly less deformation (p < 0.0001). For fracture resistance, no significant decrease was observed after aging in any group (p > 0.05). One‐piece zirconia abutments showed significantly lower strength than the other two materials for both diameters (p < 0.0001). Conclusions: In the regular diameter system, abutment material had no significant influence on the tested mechanical property degradation after simulated long‐term oral use. The mechanical performance of narrow diameter one‐piece zirconia abutments differed from the other two materials. For optimal performance, one‐piece zirconia abutments should be adopted only in anterior regions. [ABSTRACT FROM AUTHOR]

Objective: To compare MRI with 3D reconstructions and 3D-CT with respect to assessment of glenoid wear in osteoarthritic shoulders. Methods: 3D reconstructions were generated for CT and MR (utilizing the Dixon technique) imaging performed on 29 osteoarthritic shoulders. Two reviewers independently performed glenoid morphometric measurements and evaluated glenoid erosion. Mean differences between the two modalities were calculated. Inter-observer agreement was calculated using kappa coefficient. Results: The combined mean absolute difference (bias) in glenoid version between 3D-CT and 3D-MRI was 2.7° ± 1.6° (range 0.15–7.85, P value = 0.7). The combined mean absolute difference in glenoid inclination between 3D-CT and 3D-MRI was 6.8° ± 4.1° (range 0.8°–15.75°, P value = 0.17). No significant inter-reader variation in glenoid version and inclination measurements on 3D-CT and 3D-MRI was found (P > 0.05). The inter-reader reliability for both CT and MRI was high for Walch grading of glenoid bone loss (κ = 1, κ = 0.81, respectively). Conclusions: 3D-MRI is comparable to 3D-CT with respect to axial glenoid bone loss, as measured by glenoid version. However, for coronal bone loss estimation, measured by glenoid inclination, 3D-CT remains the gold standard. Thus, 3D-MR can be used as an alternative for preoperative assessment of glenoid version in arthritic shoulders. [ABSTRACT FROM AUTHOR]

Objective: To establish a baseline reference and create a user-friendly chart for normal body surface area (BSA) in the adult domestic cat similar to the "Rule of Nines" chart. Design: Prospective cadaveric study. Setting: University Teaching Hospital. Animals: Seven adult domestic short-haired feline cadavers of normal body condition (4-6/9) and body weight. Intervention: Individual whole-body computed tomography (CT) scan was performed on all cats. Images were analyzed with 3-dimensional technology to measure the BSA. A chart was created, illustrating the individual surface area of each body part. Measurements and Main Results: Obtained measurements of the cats are different from surface areas of people and dogs. Percentage of total BSA for cats was as follows: head 13%, neck 5%, thorax 20%, abdomen 15%, pelvis and tail 9%, front legs 7% each, and pelvic legs 12% each. Conclusion: The distribution of BSA between body parts is different in cats compared to dogs and people. A species-specific chart was created to assure a more accurate estimation of BSA in cats. [ABSTRACT FROM AUTHOR]

We describe the novel transcatheter approach, with off-label application of LAA closure device, coiling, and concurrent left anterior descending stenting in the setting of left ventricular (LV) pseudoaneurysm. This case underlines collaboration among interventional cardiology, cardiothoracic, and neurosurgery teams in a challenging, nonsurgical candidate with high risk of LV pseudoaneurysm rupture, and death. (Level of Difficulty: Advanced.)

Mitral valve replacement with subvalvular preservation is a favorable technique to protect left ventricular function and improve long-term survival. However, complications of the procedure should be considered. We report the case of a patient with a history of prosthetic mitral valve replacement with severe intermittent transvalvular mitral regurgitation and reduced ejection fraction. (Level of Difficulty: Advanced.)

A hypothermic avalanche victim underwent, during extracorporeal warming from asystolic arrest, 3-dimensional transesophageal echocardiography. At 33°C core temperature, left ventricular ejection fraction had recovered, whereas myocardial strain still demonstrated significant dysfunction until 36°C. Deformation analysis seems more sensitive than global assessment during myocardial recovery from hypothermic cardiac arrest. (Level of Difficulty: Intermediate.)

We describe a case of an adult patient with embolization of a varicocele coil (7 × 70 mm) to the right ventricle. We review the multimodality imaging techniques used to identify location and the importance of a multidisciplinary approach in determining management. (Level of Difficulty: Advanced.)

Primary tricuspid valve (TV) disease is rare and associated with high operative mortality. Optimal surgical planning requires a precise understanding of the pathological features; however, detailed imaging of the TV can be challenging. We present 4 cases of primary TV disease where 3-dimensional printing was pivotal to operative planning and success. (Level of Difficulty: Advanced.)

We present a rare case of cardiogenic shock and multivessel coronary compression due to focal pericardial inflammation and constriction. The patient was treated in the acute phase with coronary stenting and temporary mechanical support. Multimodality imaging was essential in elucidating the diagnosis. (Level of Difficulty: Beginner.)

Atrial fibrillation is the most common arrhythmia in clinical practice with indication for anticoagulation in those patients whose annual risk for thromboembolism is >2%. Left atrial appendage closure is growing as an alternative to anticoagulation. We present a case of pulmonary artery-left atrial appendage fistula seen after left atrial appendage closure. (Level of Difficulty: Intermediate.)

A 25-year-old male patient with a giant right atrium presented with atrial tachycardia. Electroanatomic mapping revealed micro–re-entry from a low-voltage zone in the region of the right atrial appendage. Linear ablations across the low-voltage zone terminated the tachycardia. The remaining right atrial tissue was electrically normal. (Level of Difficulty: Intermediate.)

Cutting-edge 3-dimensional technologies like 3-dimensional printing and extended reality visualization provide novel, immersive ways to understand and interact with volumetric medical imaging data for preprocedural planning. We present a case that illustrates the utility of these techniques in a patient requiring a complex transcatheter intervention., Competing Interests: The authors have reported that they have no relationships relevant to the contents of this paper to disclose., (© 2024 The Authors.)

Accurate echocardiographic evaluation of the systemic right ventricle is challenging because of its specific morphology and contraction patterns. We present a detailed multimodality assessment of the systemic right ventricle, analyze the relative contribution of the longitudinal, radial, and anteroposterior components of systolic function, and identify reasons for a potential discrepancy among imaging modalities. (Level of Difficulty: Intermediate.)

Background: Immediate implant placement (IIP) associated with the use of bone substitutes and collagen matrices (CM) seems to reduce the amount of resorption at peri‐implant areas. Recently, customized healing abutments (CA) appeared as another solution in order to seal the socket and preserve the original soft tissue contour. Purpose To evaluate peri‐implant tissues dimensional changes after using customized healing abutments compared with the use of xenogeneic collagen matrices as socket sealing options in flapless maxillary immediate implant placement. Material and methods: The present study was designed as a prospective, randomized, controlled clinical trial. Patients were allocated into two groups depending on the socket sealing option: in the CM group a collagen matrix was used and in the CA group a customized abutment. Digital impressions were taken prior to extraction, 1, 4, and 12 months after implant insertion and the digital files allowed to evaluate linear buccal changes (MBC) and the buccal volumetric variation (BVv) between the different time points at peri‐implant tissue areas. Additionally, mucosa variation was computed assessing the papilla presence and the midfacial mucosa height. Statistical significance was set at 0.05. Results: Twenty‐eight patients were observed during a 12‐month period. Significant differences between mean values of BVv at the first month were observed at the CM and CA group (−9.75 ± 6.65% and −4.76 ± 5.29%, respectively) (p = 0.043). At the 1‐year follow‐up, no significant differences were found in terms of BVv between the two groups, although the thin bone phenotype (≤1 mm) significantly influenced the volumetric variations that occurred in each group. No significant differences were noticed in midfacial mucosa and papillae alteration between groups, after 1 year of treatment. Conclusion: Both treatment options are predictable solutions for socket sealing in IIP, although a higher volumetric variation can be expected in the presence of thin bone phenotypes. [ABSTRACT FROM AUTHOR]

BackgroundAccurate evaluation of lymph node (LN) status is the key factor to determine the treatment and evaluate prognosis for patients with cancer. However, traditional pathological examination resulted in a 30% false-negative rate of detection of metastases in LNs. This study aimed to utilize Lugol’s iodine (I2-IK)-enhanced micro-CT imaging to reveal the 3-dimensional structure of regional LNs and decrease the false-negative rate in pathological examination.MethodsTo explore the feasibility of I2-IK-enhanced micro-CT imaging in locating metastatic lesion in LNs, nonmetastatic and metastatic LNs from mice were used to mimic the imaging process. Then, the LNs from oral squamous cell carcinoma (OSCC) patients were applied to verify the value of I2-IK-enhanced micro-CT imaging in revealing LN structure and locating metastatic lesions in LNs. The glycogen content in nonmetastatic and metastatic LNs was further detected by the use of a glycogen assay kit and periodic acid–Schiff (PAS) staining to explain the imaging differences between them.ResultsIn nude mice, 0.5% I2-IK staining for 4 h was the best parameter for normal LN. The metastatic foci in metastatic LNs were also clearly outlined in this condition. For nonmetastatic LNs from patients with OSCC, 1% I2-IK staining for 12 h was the best parameter. However, due to the increased volume of metastatic LNs, the image effect of 3% I2-IK staining for 12 h was superior to 1% I2-IK staining [tumor background ratio (TBR), 3% vs. 1%, 1.89 ± 0.10 vs. 1.27 ± 0.07, p < 0.001]. Compared with subsequent pathological sections, we found the CT intensity of metastatic foci in LNs and muscle tissues was significantly higher than in nonmetastatic regions. Meanwhile, the glycogen content of metastatic foci in LNs detected was also significantly higher than in nonmetastatic region.ConclusionsI2-IK-enhanced micro-CT imaging could identify the spatial location of metastatic foci in LNs. This will be an effective method to assist in decreasing the LN false-negative rate for cancer pathology.

Background: Accurate evaluation of lymph node (LN) status is the key factor to determine the treatment and evaluate prognosis for patients with cancer. However, traditional pathological examination resulted in a 30% false-negative rate of detection of metastases in LNs. This study aimed to utilize Lugol's iodine (I2-IK)-enhanced micro-CT imaging to reveal the 3-dimensional structure of regional LNs and decrease the false-negative rate in pathological examination. Methods: To explore the feasibility of I2-IK-enhanced micro-CT imaging in locating metastatic lesion in LNs, nonmetastatic and metastatic LNs from mice were used to mimic the imaging process. Then, the LNs from oral squamous cell carcinoma (OSCC) patients were applied to verify the value of I2-IK-enhanced micro-CT imaging in revealing LN structure and locating metastatic lesions in LNs. The glycogen content in nonmetastatic and metastatic LNs was further detected by the use of a glycogen assay kit and periodic acid–Schiff (PAS) staining to explain the imaging differences between them. Results: In nude mice, 0.5% I2-IK staining for 4 h was the best parameter for normal LN. The metastatic foci in metastatic LNs were also clearly outlined in this condition. For nonmetastatic LNs from patients with OSCC, 1% I2-IK staining for 12 h was the best parameter. However, due to the increased volume of metastatic LNs, the image effect of 3% I2-IK staining for 12 h was superior to 1% I2-IK staining [tumor background ratio (TBR), 3% vs. 1%, 1.89 ± 0.10 vs. 1.27 ± 0.07, p < 0.001]. Compared with subsequent pathological sections, we found the CT intensity of metastatic foci in LNs and muscle tissues was significantly higher than in nonmetastatic regions. Meanwhile, the glycogen content of metastatic foci in LNs detected was also significantly higher than in nonmetastatic region. Conclusions: I2-IK-enhanced micro-CT imaging could identify the spatial location of metastatic foci in LNs. This will be an effective method to assist in decreasing the LN false-negative rate for cancer pathology. [ABSTRACT FROM AUTHOR]

This report describes a high-risk case of tricuspid valve endocarditis secondary to intravenous drug abuse. Information gleaned from intraoperative transesophageal echocardiographic imaging and real-time measurements was used to effectively modify procedural hardware and successfully treat the patient using an aspiration-based strategy. (Level of Difficulty: Advanced.)

A 37-year-old man with Brugada syndrome and frequent appropriate implantable cardioverter-defibrillator shocks received an epicardial substrate ablation. During the procedure to eliminate delayed potentials, transient, marked ST-segment elevation in lead V2 was observed, particularly in the anterior right ventricle with a borderline between normal and low-voltage areas. (Level of Difficulty: Intermediate.)

Purpose: The primary aim of this study was to assess the 3-dimensional flare geometry of the Gore Viabahn VBX balloon-expandable covered stent (BECS) after fenestrated endovascular aortic repair (FEVAR) and to determine and visualize BECS-associated complications., Methods: This multicenter retrospective study included patients who underwent FEVAR between 2018 and 2022 in 3 vascular centers participating in the VBX Expand Registry. Patients with at least one visceral artery treated with the VBX and with availability of 2 post-FEVAR computed tomography angiography (CTA) scans (follow-up [FU] 1: 0-6 months; FU2: 9-24 months) were included. The flare geometry of the VBX, including flare-to-fenestration distance, flare-to-fenestration diameter ratio, flare angle, and apposition with the target artery were assessed using a vascular workstation and dedicated CTA applied software., Results: In total, 90 VBX BECS were analyzed in 43 FEVAR patients. The median CTA FU for FU1 and FU2 was 35 days (interquartile range [IQR], 29-51 days) and 14 months (IQR, 13-15 months), respectively. The mean flare-to-fenestration distance was 5.6±2.0 mm on FU1 and remained unchanged at 5.7±2.0 mm on FU2 (p=.417). The flare-to-fenestration diameter ratio was 1.19±0.17 on FU1 and remained unchanged at 1.21±0.19 (p=.206). The mean apposition length was 18.6±5.3 mm on FU1 and remained 18.6±5.3 mm (p=.550). The flare angle was 31°±15° on FU1 and changed to 33°±16° (p=.009). On FU1, the BECS-associated complication rate was 1%, and the BECS-associated reintervention rate was 0%. On FU2, the BECS-associated complication rate was 3%, and the BECS-associated reintervention rate was 1%., Conclusions: The flare geometry of the VBX bridging stent did not change significantly during 14 months follow-up in this study. Three-dimensional geometric analysis of the flare may contribute to identify the origin of endoleaks and occlusions, but this should be confirmed in a larger study including enough patients and BECS to compare complicated and uncomplicated cases., Clinical Impact: The three-dimensional flare geometry of the Gore Viabahn VBX BECS was assessed on the first and second postoperative CTA scans, and geometrical changes during this period were identified. For BECS that were diagnosed with a type 3c endoleak or occlusion, the BECS geometry was analyzed to detect geometrical components that were related to the complication. Geometric analysis of the flare may help to better detect and identify the cause of such complications., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: CZ has consulting, research support, honoraria, and travel support from: W.L. Gore & Associates.

We report on the feasibility of rapid, high-resolution, 3-D swept-source optical coherence tomography (SSOCT) to detect early airway injury changes following smoke inhalation exposure in a rabbit model. The SSOCT system obtains 3-D helical scanning using a microelectromechanical system motor-based endoscope. Real-time 2-D data processing and image display at the speed of 20 frames/s are achieved by adopting the technique of parallel computing. Longitudinal images are reconstructed via an image processing algorithm to remove motion artifacts caused by ventilation and pulse. Quantitative analyses of tracheal airway thickness as well as thickness distribution along tracheal circumference are also performed based on the comprehensive 3-D volumetric data.

Purpose: For proper preoperative planning of oral implants, the need has increased for tomographic imaging for precise determination of anatomic dimensions. However, concern for radiation exposure, which is substantial with computerized tomography (CT), has also grown. In the present study, the validity of jawbone width assessment and delineation by means of cone-beam CT (CBCT) and spiral tomography on dry mandibles was compared. Secondly, the subjective image quality of CBCT images with those obtained by multi-slice spiral CT (MSCT) of a fixed ex vivo cadaver with its soft tissues was compared. Materials and Methods: The study included 25 dry human mandibles for the dimensional study and 1 formalized maxilla for image quality assessment. Measurements of the mandibles by means of a digital sliding caliper acted as the gold standard. Radiographic examination of the premolar and canine regions was performed with both CBCT and spiral tomography. Observational measurements were carried out by postgraduates in oral imaging. Subjective image quality was assessed on the fixed maxilla, including soft tissues, by comparing CBCT and MSCT. Inter- and intraobserver variability were determined. Results: Direct mandibular measurements were on average 0.23 mm (SD 0.49) and 0.34 mm (SD 0.90) larger than the CBCT and spiral tomography measurements, respectively. Subjective image quality of the CBCT was significantly better than for the MSCT with regard to visualization and delineation of the lamina dura and periodontal ligament space. Subjective image quality of the MSCT was significantly better for the MSCT than the CBCT for the gingiva and cortical bone. Conclusions: These results indicate that on dry mandibles, jawbone width measurements by means of CBCT and spiral tomography are reliable, even if on average they slightly underestimate the bone width. For the subjective image quality, the CBCT offered better visualization of details of the small bony structures. Spiral tomography offered better visualization of the cortical bone and the gingiva. [ABSTRACT FROM AUTHOR]

To date, attempts to regenerate functional periodontal tissues (including cementum) are largely unsuccessful due to a lack of full understanding about the cellular origin (epithelial or mesenchymal cells) essential for root cementum growth. To address this issue, we first identified a rapid cementum growth window from the ages of postnatal day 28 (P28) to P56. Next, we showed that expression patterns of Axin2 and β-catenin within cementum-forming periodontal ligament (PDL) cells are negatively associated with rapid cementum growth. Furthermore, cell lineage tracing studies revealed that the Axin2+-mesenchymal PDL cells and their progeny rapidly expand and directly contribute to postnatal acellular and cellular cementum growth. In contrast, the number of K14+ epithelial cells, which were initially active at early stages of development, was reduced during rapid cementum formation from P28 to P56. The in vivo cell ablation of these Axin2+ cells using Axin2CreERT2/+; R26RDTA/+ mice led to severe cementum hypoplasia, whereas constitutive activation of β-catenin in the Axin2+ cells resulted in an acceleration in cellular cementogenesis plus a transition from acellular cementum to cellular cementum. Thus, we conclude that Axin2+-mesenchymal PDL cells, instead of K14+ epithelial cells, significantly contribute to rapid cementum growth. [ABSTRACT FROM AUTHOR]

Background. Distinct, irregular, and hard nodular protuberances similar to the morphologic features of exostoses can occasionally be noted on the labial surface of the alveolar bone after orthodontic retraction of anterior teeth in adults. These have long been believed to be exostoses developed in response to loading. However, specific characterization of this phenomenon has not been documented. Case Descriptions. Three cases of patients displaying multiple irregular labial bony protuberances after retraction of anterior teeth are reported. These protuberances appeared during retraction and became more prominent with additional retraction. Serial clinical photographs, lateral cephalograms, digital models, and cone-beam computed tomography scans were evaluated. On the basis of 3-dimensional superimpositions of digital models and cone-beam computed tomographic scans, the irregular protuberances appear to be the result of differential alveolar bone modeling, with more resorption of bone covering the tooth root than that of interdental bone, and not of true bone overgrowth or deposition (that is, exostoses). Conclusion and Practical Implications. Orthodontic patients often seek treatment to improve occlusion as well as esthetics. Although this study shows that these protuberances are the result of differential modeling, they may still be perceived by patients as "outgrowths," which may cause concerns related to esthetics or comfort. Clinicians should note that these protuberances are a possible outcome when large amounts of bodily retraction and root movement of anterior teeth are planned. Patients who experience psychosocial problems with this phenomenon may be candidates for alveoloplasty. [ABSTRACT FROM AUTHOR]

Three-dimensional transesophageal echocardiography and 4-dimensional flow magnetic resonance imaging as complementary techniques in the preoperative planning of a mitral paravalvular leak allow the evaluation of its location, shape, and size and qualitative-quantitative analysis of mitral regurgitant orifice. (Level of Difficulty: Intermediate.)

Background/Objective Three-dimensional images have become an important tool in understanding surgical anatomy. This paper describes a simple method for obtaining endoscopic 3-dimensional anatomic images for teaching purposes. Methods This method uses a single endoscope that provides regular, two-dimensional images. Obtaining the three-dimensional image requires the superposition of two similar but slightly different images of the same object. The set of images, one mimicking the view of the left eye and the other mimicking the view of the right eye, constitute the stereoscopic pair of images obtained with the endoscope. To construct 3-dimensional images, the distance between the pictures must approximate the interpupillary distance. Results The technique involves fixing the endoscope in position using a self-retracting arm and placing the specimen on a simple sliding tray with an adapted millimeter scale to control the distance between the pictures. The initial still image is captured and the tray on which the specimen sits is shifted up to 3–4 mm laterally to capture the second image. As a general rule, one can calculate the distance between the pictures by moving the specimen laterally 1/30 of the distance between the lens and the object. Images captured are processed using anaglyphic technique for printing and horizontal-vertical polarization of light for presentation to larger audiences. Conclusions Images produced in this way may aid in the understanding of the depth of different structures and ease of learning curve for the use of the endoscopy in neurosurgery. Highlights • 3D endoscopic anatomical images can be produced using a shoot-shift-shoot method. • It requires a single 2D endoscope, which is available in most neurosurgical centers. • This method is useful in producing 3D endoscopic anatomical images for teaching purposes. [ABSTRACT FROM AUTHOR]

Background: Supraspinatus muscle atrophy is typically assessed by the occupation ratio of the cross-sectional area of the muscle belly to the supraspinatus fossa at the medial border of the coracoid process in a slice along the oblique-sagittal plane on MRI. Previous studies have shown that the occupation ratio of the supraspinatus changed soon after rotator cuff repair compared with before surgery. However, no studies have examined the perioperative change in the muscle volume assessed with 3-dimensional measurement. Purpose: To compare the volume of the supraspinatus muscle before and soon after surgery by using 3-dimensional imaging and to elucidate whether the changes in the occupation ratio represent corresponding changes in the muscle volume. Study Design: Cohort study; Level of evidence, 3. Methods: Thirty shoulders of patients who underwent arthroscopic rotator cuff repair were evaluated. T2-weighted images were obtained before surgery and 2 weeks after surgery. After the muscle and its tendon borders were plotted, the supraspinatus and its tendon were segmented with interactive thresholding in all slices. The 3-dimensional images were then reconstructed and the volumes calculated. Changes in the muscle volume and the occupation ratio were evaluated via 3-dimensional and 2-dimensional image assessments. The 3-dimensional and 2-dimensional findings before and after surgery were compared by use of paired t tests. Results: The mean muscle volume did not change significantly at a time point soon after surgery in any group. In patients with little medial retraction (n = 7) or isolated detachment at the superior facet (n = 17), no significant differences were noted in the occupation ratio after surgery compared with before surgery. In contrast, in patients with moderate medial retraction (n = 23) or extended tearing in the transverse direction (n = 13), the occupation ratio increased significantly. Conclusion: Although the muscle volume did not change soon after surgery compared with the preoperative values, in patients with moderate medial retraction or extended tearing in the transverse direction, the occupation ratio increased, probably due to lateral traction of the supraspinatus muscle. We recommend that MRI findings obtained soon after surgery be used as the time zero reference for evaluating the postoperative changes in the supraspinatus. [ABSTRACT FROM AUTHOR]

Standardized recommended techniques for performing and reporting CT colonography (CTC) examinations were developed by a consensus of experts. Published reporting guidelines, known as the CT colonography reporting and data system supplemented by recently updated comprehensive recommendations were incorporated into the American College of Radiology (ACR) practice guidelines. The application of continuous quality improvement to the practice of CT was aided by the development of an ACR national data registry (NRDR) for CTC that addressed both process and outcome quality measures. These measures can be used to benchmark an institution’s CTC practice as compared to all participants. This article will discuss the best practices for reporting CTC and describe the use of NRDR to foster quality CTC performance. [ABSTRACT FROM AUTHOR]

Dudak damak yarıkları yüz yapılarında en sık görülen konjenital anomalidir. Ülkemizde 1/800 oranında görülmektedir. Bu anomaliye sahip bireylere ameliyat öncesi ortopedik uygulamalar yaygın biçimde yapılmaktadır. Bu olgu sunumunun amacı, 3 boyutlu görüntüleme tekniği kullanılarak ameliyat öncesi nazoalveolar şekillendirme ve ameliyat sonrasında elde edilen değişiklikler açısından bilateral dudak damak yarıklı bir bebeğin tedavi sonuçlarını değerlendirmektir.Dudak damak yarıkları yüz yapılarında en sık görülen konjenital anomalidir.1 Ülkemizde 1/800 oranında görülmektedir.2 Dudak damak yarıklı bebeklerde en önemli sorun beslenme zorluğudur. Bunun yanı sıra, bu bireylerde işitme kaybı ve ağız kokusu görülmekte; ayrıca dental arklarda eksik ve/veya malforme diş bulunabilmektedir.3,4 İleri dönemlerde kendine güvende yetersizlik, konuşma güçlüğü ve konuşma bozukluğu, bunlara bağlı olarak öğrenmede güçlük ve sosyal izolasyon karşılaşılan diğer problemlerdendir