Multiplanar Reconstruction Research Articles

Prevalence and characteristics of facial nerve bifurcation in the mastoid segment: a retrospective analysis using temporal bone CT scans.

To investigate the prevalence and characteristics of bifurcation of the facial nerve (FN) in the mastoid segment using temporal bone CT scans. A total of 970 cases (1931 ears) of temporal bone CT scans were reviewed, including 463 females and 498 males, aged 1 to 95years (interquartile range: 20-69years). CT imaging with multiplanar reconstruction (MPR) was used to identify and evaluate the bifurcation of the FN. Cases showing branching were confirmed by consensus among three physicians. We identified 10 cases (10 ears) with facial nerve branching in the vertical segment, yielding an incidence rate of 0.52% (10/1931 ears). Every cases were unilateral, predominantly on the left side. Age analysis revealed 1 case (0.22%) in individuals under 20years and 9 cases (0.61%) in those over 20years. Bifurcation generally occurred near the middle to lower vertical segment, with the closest proximity to the second genu observed in a 15-year-old patient. Bifurcation of the FN in the mastoid segment, though rare, can be encountered in otologic surgery. Detailed preoperative imaging evaluations are crucial for surgical planning to minimize the risk of nerve damage. Our findings emphasize the importance of recognizing anatomical variations in the FN for improving surgical outcomes and patient safety.

Curved multiplanar reformatting allows the accurate histological delineation of hippocampal subfields.

Hippocampal subfields perform specific roles in normal cognitive functioning and have distinct vulnerabilities in neurological disorders. However, measurement of subfields with MRI is technically difficult in the head and tail of the hippocampus. Recent studies have utilized curved multiplanar reconstruction (CMPR) to improve subfield visualization in the head and tail, but this method has not yet been applied to histological data. We utilized BigBrain data, an open-source database of serially sectioned histological data for our analyses. The left hippocampus was segmented according to histological criteria by two raters in order to evaluate intra- and inter-rater reliability of histology-based segmentation throughout the long axis. Segmentation according to our previous protocol for the hippocampal body was then compared to these histological measurements to evaluate for histological validity. Agreement between segmentations was evaluated using Dice similarity coefficients (DSCs). Intra-rater reliability (DSCs) of histological segmentation was excellent for all subfields: CA1 (0.8599), CA2 (0.7586), CA3/CA4/DG (0.8907), SLM (0.9123), subiculum (0.8149). Similarly, inter-rater reliability analysis demonstrated excellent agreement (DSCs) for all subfield locations: CA1 (0.8203), CA2 (0.7253), CA3/CA4/DG (0.8439), SLM (0.8700), subiculum (0.7794). Finally, histological accuracy (DSCs) for our previous protocol was excellent for all subfields: CA1 (0.8821), CA2 (0.8810), CA3/CA4/DG (0.9802), SLM (0.9879), subiculum (0.8774). When subfields in the hippocampus head, body, and tail were analyzed independently, DSCs also showed excellent agreement. CMPR allows reliable subfield segmentation based on histological criteria throughout the hippocampal head, body, and tail. Our previous protocol for the hippocampal body can be applied to provide histologically valid subfield measurements throughout the entire hippocampal long axis.

Identification of gunshot entry wounds using hyperdense rim sign on post-mortem computed tomography.

Post-mortem computed tomography (PMCT) is an increasingly utilized tool in forensic medicine for evaluating head gunshot injuries. Vault bevelling sign, when present, provides information regarding entry and exit wounds; when absent, identifying wound type on PMCT remains challenging. A cutaneous hyperdense ring, described in an animal study by Junno et al. (2022), may be indicative of contact shots. We hypothesized that it could also be observed in human gunshot injuries. Our study evaluates the reliability of the cutaneous hyperdense rim sign for identifying entry gunshot wounds in PMCT. After excluding complex and mucosal wounds, two operators retrospectively evaluated 64 gunshot wounds (30 entry and 34 exit wounds) in 34 head PMCT cases (2018-2022). Gold standard for wound type determination was the autopsy report. The hyperdense rim sign was defined as at least two-thirds of a continuous cutaneous hyperdense circle on a multiplanar reconstruction of cutaneous tissue tangent to the wound. The hyperdense rim sign demonstrated a specificity of 97% (95% CI: 85-100%) and a sensitivity of 63% (95% CI: 44-80%) for identifying entry wounds. Moreover, in 16 external examination reports where the presence of powder residues or bullet wipe at entry wound was explicitly mentioned, a positive association was observed between hyperdense rim sign and the presence of these elements (p = 0.018). These findings suggest that the hyperdense rim sign, when present, may be a valuable tool for entry wound determination in gunshot injuries, interpreted in conjunction with other CT and autopsy features.

Standardized 3D Transoesophageal Echocardiography Manoeuvre for Enhanced Tenting Height Evaluation During Transcatheter Mitral Valve Edge-to-Edge Repair.

Background: Transcatheter treatments for structural heart disease, including edge-to-edge mitral valve repair (mTEER), heavily rely on transoesophageal echocardiography (TOE) for pre-procedural assessment and guidance. Trans-septal puncture (TSP) is one of the first key steps of such procedures, with two-dimensional (2D) TOE often providing suboptimal imaging. Three-dimensional (3D) echocardiography could overcome the limitations of 2D TOE and improve the assessment of tenting height. Methods: This single-centre, retrospective study included 64 patients who underwent mTEER between October 2023 and April 2024. Tenting height during TSP was assessed by 2D TOE in mid-oesophageal (ME) four-chamber view and by 3D TOE after the acquisition of a 3D volume, including the interatrial septum, aortic valve, and mitral valve, and subsequent multiplanar reconstruction (MPR). A total of 100 TSP attempts with 2D and 3D TOE were evaluated. Results: Procedural success was obtained in 92.2% of cases. There was a statistically significant difference between 2D and 3D measurements (2D: 4.36 ± 0.61 cm, MPR: 4.59 ± 0.63 mm2, p < 0.001), despite good correlation (r = 0.880, p < 0.001). The difference between 2D and 3D tenting height measurements differed significantly between patients with optimal and suboptimal 2D image windows (p < 0.001). There was no significant difference in septal puncture success between optimal 2D and 3D data (p = 0.942). Conclusions: Adopting 3D TOE with multiplanar reconstruction for assessing tenting height in mTEER procedures offers significant advantages over traditional 2D TOE. Enhanced visualization, accuracy, and potential for standardization improve procedural outcomes and patient safety, making 3D TOE integration into routine practice highly beneficial and recommended.

Speeding up echocardiographic examination by automated generation of 2D imaging views from 3D volumetric data using machine learning

Abstract Background 3D echocardiographic data contain infinite 2D echocardiographic planes generated by multiplanar reconstruction, but the process is labor-intensive and time-consuming. Artificial intelligence (AI) utilizing cutting-edge machine learning techniques may improve the accuracy and efficiency of the process. In the study, we developed and validated an AI software that automatically reconstructs 7 2D views recommended by the American Society of Echocardiography from 3D echocardiographic data. Method Convolutional neural network (CNN) architecture utilizing Spatial Configuration Net was used as the machine learning model. We identify a minimum of 3 key feature landmarks on each 2D cross-sectional plane, with the 3D coordinates representing 2D cross-sectional planes accordingly. Subsequently, these landmarks are accurately labeled within a 3D space. 31 landmarks were identified across 7 2D cross-sectional planes and a total of 472 3D volume data were labelled. The performance of the model is evaluated by Root Mean Square Error (RMSE) of the predicted landmark coordinates. Results The mean RMSE over 31 predicted landmarks evaluated in testing is 2.70% for the input 3D volume dimensions. The average time used to generate the 7 2D imaging views was 19.91±3.19 seconds (figure). Conclusion The AI algorithm can efficiently convert 3D echocardiographic data into guideline-recommended 2D images, which shortens the length of echo examination but still preserves the accuracy.AI generation of 2D views from 3D echo

Excluding significant coronary artery disease in patients planned for TAVR using CT: Diagnostic accuracy of newest generation dual source photon counting scanner compared to coronary angiography

Abstract Introduction Patients with significant aortic stenosis routinely undergo CT for evaluation of the aortic root prior to interventional aortic valve replacement (TAVR). Assessment of CAD is usually performed by invasive coronary angiography. We assessed the diagnostic accuracy of the latest generation dual source photon counting scanner for exclusion of relevant CAD in a contemporary TAVR cohort. Methods Patients referred for cardiac CT prior to transcatheter aortic valve implantation were screened for inclusion this analysis. All cardiac CT exams were performed by dual source photon counting scanner (NAEOTOM alpha, Siemens healthineers, Germany). CT acquisitions were performed using retrospectively triggered spiral acquisition (30-70% of the cardiac cycle) without ultra-high resolution. For each patient, several reconstructions were rendered (thin slice reconstruction with 0.4 mm slice thickness: best diastolic phase, best systolic phase, 200-350 ms folllowing R-wave in 50 ms intervals as well as 0.6 mm slice thickness multiphase reconstruction 0-90% of the cardiac cycle in 10 % increments). Assessment of significant CAD was performed in CT and invasive angiography on a per-vessel analysis and a per-patient analysis using 2 thresholds: ≥ 50% stenosis and ≥ 70% stenosis. Assessment of stenoses in CT was performed using multiplanar reconstructions (MPR) and curved MPR and only in vessels &amp;gt; 1.5mm diameter. Assessment of stenosis in invasive angiography was performed using the projection with the most relevant lumen reduction. Image quality in CT was assessed on a likert scale from 1 to 4 (1=excellent, 2=minor artifacts, 3=major artifacts still assessable, 4=non-assessable). Results In this analysis 31 consecutive patients were included (mean age 79.5y, 64.5% males, 35.5% females). Mean heart rate was 66.5 bpm and 19% were in atrial fibrillation during CT acquisition. Mean image quality was 1.4. 13 Patients had no relevant CAD (stenosis ≥50%) in invasive angiography and in 18 patients at least 1 vessel was deemed to have ≥ 50% stenosis in invasive angiography. On a per vessel analysis, sensitivity, specificity and accuracy of cardiac CT to exclude stenoses using 50% and 70% thresholds were 98%, 93% and 94% vs. 97%, 93% and 94%, respectively. Negative likelihood ratio was 0.02 vs. 0.03 respectively. On a per-patient level, sensitivity and specificity were 100%. Out of 31 patients, only 2 vessels in 2 patients were deemed non-assessable. 3 patients with previous PCI as well as 3 patients with previous CABG were included in this analysis. Only 1 false negative vessel was reported in a very distal LAD segment. Conclusion Using newest generation dual source CT with photon counting, CT allowed highly reliable diagnostic workup regarding the presence of CAD in this TAVR cohort. The use of CT to assess CAD in TAVR patients seems clinically feasible especially in patients without previous percutaneous revascularisation.

Minor's Syndrome or Dehiscence of the Superior Semicircular Canal: A Case Report

Semicircular canal dehiscence is a congenital syndrome that mainly affects the superior and, less commonly, the posterior semicircular canal in the temporal bone. This syndrome was first reported by Minor et al. in 1998. The prevalence is about 0.5% in the general population. The most characteristic symptom is the Tullio phenomenon, predominantly vertigo and nystagmus. Hearing loss (in particular conductive loss) often completes overall clinical picture. The dehiscence may be completely asymptomatic, in which case it is seen as an incidental finding on radiological investigations. Audiological evaluation includes audiometry and vestibular evoked myogenic potentials (VEMPs). Clinical symptoms are based on the pathophysiological concept of a third mobile window within the inner ear. Diagnosis is confirmed by high resolution petrous temporal bone CT with multiplanar reconstructions (MPRs) in the plane of the canal (Pöschls’ plane for the superior semicircular canal) and 3-D surface reconstructions. MR findings are less sensitive for this entity. The most common differential diagnosis is otosclerosis. Clinical–radiological correlations have therapeutic applications even though the indication for surgery depends on the severity of the vestibular symptoms.

3D transesophageal echocardiographic assessment of acute reverse remodeling of the tricuspid annulus after transcatheter edge-to-edge repair.

Our study aims to evaluate the acute remodeling of the tricuspid valve annulus immediately after the T-TEER by using intraprocedural transesophageal three-dimensional (3D) echocardiography. We prospectively enrolled 62 consecutive symptomatic patients with at least severe TR, who underwent T-TEER with the TriClip System between March 2021 and June 2024. The following parameters were assessed using a multiplanar reconstruction analysis performed off-line using a 3D dataset: septal-lateral (SL) and antero-posterior (AP) annulus diameters; annulus area; annulus perimeter and eccentricity index.The acute procedural success was achieved in 85,5%. We observed an acute reduction in SL (from a median of 43 to 38 mm, p<0,0001), AP (from a median of 46 to 45 mm, p<0,0001), area (from a median of 17,9 to 15,95 cm2, p<0,0001), perimeter (from a median of 145,5 to 137 mm, p<0,0001) and eccentricity index (from 0,92 to 0,87, p<0,0001). The TV annulus was progressively larger in patients with higher residual TR. Analysis of the subgroups according to procedural success showed an acute inverse remodeling of the TV annulus independent of the acute procedural success. The TV geometry necessitates the use of 3D echocardiography for accurate assessment of annular remodeling post T-TEER. The reduction in TR grade and TV annulus dimensions begins immediately after TriClip implantation. Concurrently, the baseline TV geometry influences the procedural results.

Algorithms in acetabular fracture classifications.

Acetabular fractures are still challenging fractures. Fracture classification is the basis for understanding these injuries and to gain treatment and to choose a fracture type-based treatment concept. Using a systematic step-wise concept of fracture analysis, based on specific radiographic lines on standard X-rays allow even less experienced surgeons to get a correct classification of the elementary and associated fracture types of Letournel's classification. Algorithmic analysis of the iliopectineal line, (anterior column involvement), ilioischial line (posterior column involvement), presence of a posterior wall fragment, fracture lines involving the iliac wing and inferior ramus, and the spur sign (representing associated both column fractures) allow for approximately 80-90% correct classifications using standard X-rays when integrating these lines into an algorithm. Especially, T-shaped fractures, ABC and ACPHT fractures may be difficult to classify. Thus, advanced imaging, such as CT scans with multiplanar reconstruction and 3D reconstructions is additionally recommended.

Radioanatomical evaluation of the subtympanic sinus in children under five years old and its clinical implications - high resolution computed tomography study.

This study aimed to evaluate subtympanic sinus (STS) and its vicinity in high-resolution computed tomography (HRCT) scans of children under five years old with non-diseased temporal bones. We divided the whole group into children under 24 months of age (first stage of pneumatisation development) and between 25 and 60 (second stage). We have determined the width of the entrance to STS, depth of the STS, type in relation to facial nerve according to Anschuetz classification, the pneumatisation of posterior and medial air cell tracts, and jugular bulb position. All the HRCTs (280 temporal bones) were analyzed according to the multiplanar reconstruction protocol with symmetrization. STS's mean width and depth were 2.71 ± 0.60mm and 3.26 ± 1.11mm, respectively. The most common STS type was type A (59.3%), followed by type B (30.7%) and type C (10%). The posterior air cell tract (retrofacial cells) was present in 39.3%. The medial air cell tract (hypotympanic cells) was present in 30.7% The jugular bulb position affected the final shape of STS in 17.5%. The results support the necessity of the classification for the STS. Our study may help with surgical planning regarding endoscopic ear procedures and gives a broader understanding of how pneumatization or jugular bulb might correlate with the final shape of the retrotympanum. The historical remarks track the term's origin for clarity in research and respect for earlier investigators.

Measurement and analysis of condylar morphology and thickness of the roof of the glenoid fossa in patients with unilateral second molar scissor bite

Objective The objective of this study was to measure and analyze the joint space, condylar morphology, and thickness of the roof of the glenoid fossa (RGF) in patients with unilateral second molar scissor bite using cone beam CT (CBCT). Methods A total of 80 patients were included in this study. Forty patients with a normal posterior occlusal relationship, who attended the Department of Orthodontics at the First Hospital of Shanxi Medical University from December 2021 to August 2023, were selected as the control group. The experimental group consisted of 40 patients with unilateral second molar scissor bite during the same period. All patients underwent CBCT scanning, and the resulting images were analyzed using the NNT viewer software in multiplanar reconstruction (MPR). Axial, coronal, and sagittal adjustments were made for each patient. Results In the control group, the right and left joint spaces (PS, SS, AS), the height of the upper part of the condyle, and the depth of the glenoid fossa did not show statistically significant differences (P > 0.05). When comparing bilateral condylar morphology and joint space in the experimental group, it was found that the posterior joint space on the scissor bite side was greater than that on the normal occlusion side, while the anterior joint space on the scissor bite side was smaller than that on the normal occlusal side. Additionally, the height of the upper condyle and the depth of the glenoid fossa on the scissor bite side were greater than that on the normal occlusal side, with statistically significant differences (P < 0.05). However, there were no statistically significant differences in SS, internal and external joint diameter, as well as anterior and posterior diameters (P > 0.05). The comparison of the minimum thickness of the roof of the glenoid fossa in both the sagittal and coronal directions between the patients in the experimental group and the control group showed no statistically significant difference (P > 0.05). Furthermore, the asymmetry index of the supracondylar height in the control group was significantly smaller than that in the experimental group, displaying a statistically significant difference (P < 0.05). The differences in the asymmetry indices of the anterior and posterior diameters of the condyle, as well as the inner and outer diameters, were not statistically significant (P > 0.05). When analyzing the position of the condyle in the sagittal direction of the glenoid fossa in the patients of the control group, it was observed that the majority were in the anterior and medial positions, with only 10% and 5% being in the posterior position. However, the analysis of the condyle position in the sagittal direction of the glenoid fossa in the experimental group revealed statistically significant differences (P < 0.05), with the condyle position on the scissor bite side being more anterior. Conclusion Unilateral second molar scissor bite can result in anterior displacement of the condyle, greater height of the condyle superiorly as well as the depth of the glenoid fossa.

Approach to frontal sinus via five frontal sinus drainage pathways.

This study aimed to validate a method for successful frontal sinus surgery. The method classifies the frontal sinus drainage pathway (FSDP) into five categories based on three bony walls of the anterior ethmoid sinus, including the uncinate process (UP), accessory uncinate process (UPa), and basal lamella of the ethmoid bulla (BLEB), which was tested in actual surgical procedures. This study analyzed 53 sides of 48 patients who underwent frontal sinus surgery between October 2022 and March 2023. We classified the FSDPs using preoperative computed tomography (CT) and multiplanar reconstruction (MPR). During surgeries for FSDPs located anterior to the BLEB, we used a two-step method involving resection of the turbinal UP, followed by upward resection from the lower edge of the ethmoidal UP. For FSDPs located posterior to the BLEB, we resected the BLEB at the superior semilunar recess. We confirmed the origin of each of the five types of FSDP during surgery. These origins, which were located at the lowest part of the anterior ethmoid, could be identified in the early stages of ethmoid sinus surgery before proceeding to the frontal recess area. The origins of the five types of FSDP, classified based on the bony walls, can be clearly and accurately identified during surgery. This provides a reliable method for preoperatively predicting and locating the inferior end of the FSDP (origin), without extensive manipulation of the cells formed in the frontal fossa.

Key Factors for Predicting Appendicitis from Contrast-Enhanced Computed Tomography Images Obtained Through Multiplanar Reconstruction

Background: The diameter of the appendix is a key parameter in diagnosing appendicitis. The diagnostic threshold for this parameter is 6 mm, originally established through graded compression sonography of the right lower quadrant (RLQ) of the abdomen. However, without corroborative findings from computed tomography (CT), this threshold may not be a reliable indicator of appendicitis. To ensure accurate diagnosis, clinicians should perform a comprehensive, multiparameter imaging assessment of the appendix, rather than relying solely on appendix diameter. Objectives: This study aimed to identify key factors for predicting appendicitis using contrast-enhanced coronal and sagittal CT images obtained through multiplanar reconstruction. Patients and Methods: This single-center, retrospective, cross-sectional study included patients who presented to our emergency department (ED) with RLQ abdominal pain and subsequently underwent contrast-enhanced CT between July 2019 and September 2020. The primary study outcome was pathologically confirmed appendicitis. Two experienced radiologists assessed parameters such as appendix diameter, wall thickness, abnormal appendix enhancement, abnormal appendix content, appendix erection, and periappendiceal fat stranding. Multivariate logistic regression was performed to identify significant predictive factors for appendicitis. Results: The study included 173 patients (median age: 37 years; women: 86). They were divided into appendicitis (n = 102) and alternative diagnosis (n = 71) groups. Significant differences were observed between the groups in terms of appendix diameter, wall thickness, wall enhancement, luminal content, appendix erection, and periappendiceal fat stranding (P &lt; 0.001). The diagnostic sensitivity and specificity values for an appendix diameter threshold of 7.7 mm were 91% and 82%, respectively. An appendix diameter of &gt; 7.7 mm (OR: 15.3; P &lt; 0.001), abnormal appendix enhancement (OR: 12.5; P &lt; 0.001), and appendix erection (OR: 6.1; P = 0.004) emerged as significant independent predictors of appendicitis. Conclusion: An appendix diameter of 7.7 mm appears to be the optimal threshold for diagnosing appendicitis. Additionally, the detection of abnormal appendix enhancement and appendix erection on contrast-enhanced CT images holds considerable diagnostic value.

Computed tomography of acute orbital trauma in children: a retrospective study

INTRODUCTION: Orbital injuries account for 36 to 64% of all blunt trauma to the facial bones. Diagnosis of orbital wall fractures is carried out using conventional radiography in several projections and computed tomography; magnetic resonance imaging is less commonly used. Often, due to the small displacement of orbital bone fragments, X-ray diagnosis is difficult. Multislice CT with reconstruction of sagittal, coronal projections and 3D in the bone window in such cases is the best visualization method. However, there are still no clear indications for the use of each method and there is no complete view of the CT characteristics of orbital damage.OBJECTIVE: To study the diagnostic value of computed tomography of orbital fractures in pediatric patients with acute trauma.MATERIAL AND METHODS: Retro- and prospectively analyzed the results of CT scans of 94 patients with facial fractures from 01/01/2023 to 09/01/2023 to assess combined orbital injuries. Orbital fractures were detected in 63 children (67.0%). There were 44 boys (69.84%), 19 girls (30.15%) aged from 7 months to 17 years 10 months (average age 10.3). Statistics: For statistical analysis, the method of calculating the nominal correlation using the Kramer coefficient (V) using the IBM SPSS Statistics software package was used.RESULTS: Concomitant injury was observed in 30 (47.6%); isolated 33 (52.36%). The number and frequency of fractures observed were as follows: superior wall of the orbit — 39 (61.9%); zygomatic complex — 19 (30.1%); lower wall of the orbit — 43 (68.2%); nasal bone — 17 (26.9%); lower jaw — 6 (9.5%); medial wall of the orbit — 28 (44.4%); upper jaw — 27 (42.8%); alveolar process — 6 (9.5%); isolated zygomatic arch — 14 (22.2%); Le Fort type I — 1 (1.5%); Le Fort type II — 2 (3.1%); and Le Fort type III — 0 (0%). Orbital hematomas were found in 25 patients (39.6%). It was revealed a strong correlation between the presence of contiguous skull fractures and multiple skull fractures (V=0.878, p&lt;0.001), frontal sinus fractures and frontal sinus hemosinus (V=0.69, p&lt;0.001).CONCLUSION: Orbital fractures are a frequent type of facial fracture occurring in children with blunt isolated and combined trauma. In children with blunt trauma, head CT combined with clinical examination is currently the optimal tool for diagnosing clinically significant orbital injuries. There is a strong correlation between orbital hematomas and orbital vault fractures, orbital hematomas and lattice fractures, adjacent skull and orbital vault fractures, and adjacent skull and lattice fractures. CT examination should include multiplanar (in coronal and sagittal planes) and 3D reconstructions, which help to assess the extent of the fracture, the presence of diastasis, the degree of muscle impingement. Based on the data obtained, the clinician determines the need for surgical intervention.

Automatic Segmentation of the Jaws Used in Guided Insertion of Orthodontic Mini Implants to Improve Their Stability and Precision.

Background and Objectives: With the goal of identifying regions with bicortical bone and avoiding root contact, the present study proposes an innovative technique for the simulation of the insertion of mini orthodontic implants using automatic jaw segmentation. The simulation of mini implants takes place in 3D rendering visualization instead of Multi-Planar Reconstruction (MPR) sections. Materials and Methods: The procedure involves utilizing software that automatically segments the jaw, teeth, and implants, ensuring their visibility in 3D rendering images. These segmented files are utilized as study models to determine the optimum location for simulating orthodontic implants, in particular locations characterized by limited distances between the implant and the roots, as well as locations where the bicortical structures are present. Results: By using this method, we were able to simulate the insertion of mini implants in the maxilla by applying two cumulative requirements: the implant tip needs to be positioned in a bicortical area, and it needs to be situated more than 0.6 mm away from the neighboring teeth's roots along all of their axes. Additionally, it is possible to replicate the positioning of the mini implant in order to distalize the molars in the mandible while avoiding the mandibular canal and the path of molar migration. Conclusions: The utilization of automated segmentation and visualization techniques in 3D rendering enhances safety measures during the simulation and insertion of orthodontic mini implants, increasing the insertion precision and providing an advantage in the identification of bicortical structures, increasing their stability.

Optimization of 3D imaging time reduction by assessing spatial resolution in the slice selective direction using the ladder method

PurposeAssessing spatial resolution in MRI is challenging due to non-linearity. Despite the widespread use of 3D imaging in clinical practice for lesion detection and multi-planar reconstruction (MPR), the extended acquisition time poses a shortcoming. To address this, the “Slice resolution” parameter is utilized; however, its impact on MPR images is unclear. This study aims to assess spatial resolution using the ladder method, investigate the effects of diverse slice resolution settings in various imaging sequences, and propose optimal conditions. MethodsImages were acquired using various 3D imaging sequences—SPACE T1WI, SPACE T2WI, and VIBE T1WI—with different slice resolutions. Axial cross-section images were acquired and reconstructed into coronal cross-sections. The ladder method was employed for objective evaluation, including spatial frequency analysis. Additionally, visual evaluation was conducted and compared with ladder method results. ResultsFor three imaging sequences, the evaluated value of ladder method remained relatively constant from 100 % to 80 % slice resolution. However, the evaluated value decreased in low-spatial frequency for slice resolution below 70 %. ConclusionsResults from both ladder method and visual evaluations indicated image quality remained stable when the slice resolution was decreased to 80 %, potentially enabling a 20 % reduction in imaging time while preserving resolution in other cross-sections reconstructed by MPR.

Application of Handheld Point-of-Care Ultrasound in the Setting of Craniomaxillofacial Trauma: A Technical Note

Computed tomography (CT) is the standard of care imaging in craniomaxillofacial (CMF) trauma. Despite the clear advantages of high-resolution multiplanar and three-dimensional (3D) reconstructions, which facilitate accurate diagnosis and provide intraoperative (IO) real-time visual feedback, CT's main drawbacks remain availability, cost, and high radiation exposure. The decision to perform a CT scan is based on the integration of the patient's trauma mechanism, clinical examination, subjective judgment of the CMF surgeon, and the complexity of the surgery if used IO. Handheld point-of-care ultrasound (HPOCUS) is a small, portable device that can provide valuable additional data directing clinical decisions for CT referral in minor trauma cases and assist IO maneuvers. We describe a novel HPOCUS application concept as a clinical supplementary tool in CMF trauma diagnosis and surgery.

Determination of Inoue Balloon Size by Analysis of Mitral Valve Geometry Using Three-Dimensional Transesophageal Echocardiography in Patients with Mitral Stenosis

In percutaneous mitral balloon commissurotomy (PMBC) for patients with mitral stenosis (MS), the size of the balloon has traditionally been determined using a crude method based on the patient's height or body surface area. We aimed to evaluate the clinical value of balloon size selection by quantitatively analyzing mitral valve (MV) geometry using 3D transesophageal echocardiography (TEE). In 184 consecutive patients who underwent PMBC, the geometry of the MV annulus was analyzed during mid-diastole, including the measurement of lateral-medial diameters obtained from dedicated 3D software (LMD-3d) or from analysis using multiplanar reconstruction images (LMD-mpr). Patients were categorized into three groups: those with successful results after PMBC (SU group), those with residual mitral stenosis (MS, group), and those with significant MR (MR group). The SU, MS, and MR groups included 110, 50, and 17 patients, respectively. We compared three conventional formulas (Formula 1, 2, 3) based on the patient's height or body surface area with two new formulas derived from data in the SU group: balloon size = 0.0684 × LMD-3d + 24.309 (Formula 4) and 0.061 × LMD-mpr + 24.573 (Formula 5). Compared with the calculated balloon sizes using Formula 4, the inflated balloon sizes were significantly smaller (-0.78±1.02; p<0.001) in the MS group, while they were significantly larger (0.56±1.05; p=0.04) in the MR group. This pattern was also consistent in Formula 5. In conclusion, selecting the Inoue balloon inflation size based on the mitral annulus diameter determined by 3D TEE might be a reasonable approach.

Web-Based DICOM Viewers: A Survey and a Performance Classification.

The standard for managing image data in healthcare is the DICOM (Digital Imaging and Communications in Medicine) protocol. DICOM web-viewers provide flexible and accessible platforms for their users to view and analyze DICOM images remotely. This article presents a comprehensive evaluation of various web-based DICOM viewers, emphasizing their performance in different rendering scenarios, browsers, and operating systems. The study includes a total of 16 web-based viewers, of which 12 were surveyed, and 7 were compared performance-wise based on the availability of an online demo. The criteria for examination include accessibility features, such as available information or requirements for usage, interface features, such as loading capabilities or cloud storage, two-dimensional (2D) viewing features, such as the ability to perform measurements or alter the viewing window, and three-dimensional (3D) viewing features, such as volume rendering or secondary reconstruction. Only 4 of the viewers allow for the viewing of local DICOM files in 3D (other than MPR(Multiplanar reconstruction)). Premium software offers a large amount of features with overall good performance. One of the free alternatives demonstrated the best efficiency in both 2D and 3D rendering but faces challenges with missing 3D rendering features in its interface, which is still in development. Other free options exhibited slower performance, especially in 2D rendering but have more ready-to-use features on their web app. The evaluation also underscores the importance of browser choice, with some browsers performing much better than the competition, and highlights the significance of hardware when dealing with rendering tasks.

Gender prediction using geometric morphometry with parameters of the cranium obtained from computed tomography images

Purpose: The gender difference of the cranium skeleton is of great importance in forensic anthropology and forensic medicine sciences. This study is based on this hypothesis and the gender prediction rate was obtained by processing cranium images obtained from computed tomography (CT) using geometric morphometry. Materials and Methods: CT images of 200 individuals between the ages of 25 and 65 were used in our study. The images were opened at the personal workstation Horos Medical Image Viewer (Version 3.0, USA) program and processed with 3D Curved Multiplanar Reconstruction (MPR). The line passing through the nasion and inion points of the images obtained as a result of the process was determined, and all images were brought to the orthogonal plane. Later, the images were overlapped and saved in JPEG format with 100% magnification. JPEG images saved were converted into TPS format, and 21 homologous landmarks were placed. Generalized Procrustes Analysis (GPA) and Principal Component Analysis (PCA) were applied to the coordinates of landmarks, and shape variations and dimensionality were corrected by gathering the images to the center of gravity. Next, Linear Discriminant Analysis (LDA) was applied to the coordinates, the dimensionality of which was corrected. Results: The study found that 74.465% of the coordinates of 21 homologous landmarks gathered to the center of gravity could be explained with the first three PCs. As a result of the LDA applied to these coordinates, a gender prediction rate of 86.5% was obtained. In addition, a slight difference was found between the GPA sum of squares and the tangent sum of squares (0.57). Conclusion: The images of the cranium obtained from CT showed a high dimorphism by geometric morphometry analysis.