Early bifurcation of the common hepatic artery: A pitfall that should be known and recognized.

Early bifurcation of the common hepatic artery (EBCHA) is a rare anatomical variation (1%), that is often overlooked but can lead to accidental ligation of the right branch of the hepatic artery with consequent arterial ischemia of the right liver and potentially very serious complications during pancreaticoduodenectomy, partial hepatectomy, or liver harvesting for transplantation. It may be difficult to diagnose EBCHA using transverse imaging sections. However, on standard CT sections with intravenous contrast injection, three warning signs should allow the image reader to suspect it: presence of two hepatic arteries to the right of the celiac trunk, presence of a retro-portal hepatic artery, and absence of a right hepatic artery arising from the superior mesenteric artery. Analysis of the CT with reconstruction then allows for definitive diagnosis and limits the risk of accidental arterial injury or ligation.

Integrating digital design with 3D printing technology achieves customized and precise approaches for flap transplantation to facilitate fingertip defect surgery.

OBJECTIVE: This study investigates the clinical efficacy of integrating digital design with three-dimension (3D) printing technology in the transplantation of flaps for fingertip defects. METHODS: A retrospective analysis was conducted from October 2019 to June 2021 on 90 cases of patients with fingertip defects. These included 45 cases in which digital design, coupled with 3D printing, assisted the operation (3D printing group), and another 45 cases where patients underwent traditional pedicle flap transplantation and skin grafting (traditional operation group). A six-month postoperative follow-up assessed various measurements between the two groups, comparing the skin flap survival rate, aesthetic outcome, cold intolerance, sensory recovery, and overall skin flap performance. RESULTS: ① Statistical analysis utilizing the independent samples t-test revealed a significant reduction in both operation time and flap anastomosis rate for the 3D printing group compared to the traditional operation group (P < 0.05). ② Conversely, the survival rate, aesthetic outcome, and cold intolerance showed no significant disparities between the groups (P > 0.05). ③ Further, the Mann-Whitney U test indicated no significant difference in sensory recovery and overall efficacy assessment between the two cohorts (P > 0.05). CONCLUSION: Integrating digital design with 3D printing technology facilitated the surgical management of fingertip defects, achieving customized and precise approaches in flap transplantation. This precision in personalized skin flap design contributed to reduced operative time and enhanced surgical efficiency in such procedures.

Computed tomography three-dimensional reconstruction in the diagnosis of bleeding small intestinal polyps: A case report.

BACKGROUND: Computed tomography (CT) small bowel three-dimensional (3D) reconstruction is a powerful tool for the diagnosis of small bowel disease and can clearly show the intestinal lumen and wall as well as the outside structure of the wall. The horizontal axis position can show the best adjacent intestinal tube and the lesion between the intestinal tubes, while the coronal position can show the overall view of the small bowel. The ileal end of the localization of the display of excellent, and easy to quantitative measurement of the affected intestinal segments, the sagittal position for the rectum and the pre-sacral lesions show the best, for the discovery of fistulae is also helpful. Sagittal view can show rectal and presacral lesions and is useful for fistula detection. It is suitable for the assessment of inflammatory bowel disease, such as assessment of disease severity and diagnosis and differential diagnosis of the small bowel and mesenteric space-occupying lesions as well as the judgment of small bowel obstruction points. CASE SUMMARY: Bleeding caused by small intestinal polyps is often difficult to diagnose in clinical practice. This study reports a 29-year-old male patient who was admitted to the hospital with black stool and abdominal pain for 3 months. Using the combination of CT-3D reconstruction and capsule endoscopy, the condition was diagnosed correctly, and the polyps were removed using single-balloon enteroscopy-endoscopic retrograde cholangiopancreatography without postoperative complications. CONCLUSION: The role of CT-3D in gastrointestinal diseases was confirmed. CT-3D can assist in the diagnosis and treatment of gastrointestinal diseases in combination with capsule endoscopy and small intestinal microscopy.

Enhancing precision of defect 3D reconstruction in metal ultrasonic testing through point cloud completion.

During the ultrasound multi-layer focused scanning inspection process, the sequential images characterizing the defect morphology suffer from inter-layer contour information loss, which causes a reduction in the accuracy of defect 3D reconstruction, subsequently leading to errors in the characterization of the defect size and morphology. In order to address the above issues, a new method based on the Attention-based Residual Completion Network (ARC) is proposed for ultrasonic point cloud completion to characterize metal defects. Firstly, the ARC network extracts global contour morphological features and local edge detail features from the ultrasonic point cloud through consecutive residual convolutions. Subsequently, the two sets of features are concatenated and finally fed into a decoder based on self-attention, realizing the reconstruction of lost contour information and enhancing the 3D reconstruction accuracy of defects. In the experiment, an ultrasonic microscope was used to inspect actual steel plates. The internal defects were then completed using the ARC network, and the completion results were compared with the metallographic images of the defects. The experiment results indicated that, after completion, the characterization accuracy of defect morphology and sizes is enhanced by an average of 10.31 %. The ARC network provides a novel method for high-precision 3D characterization of internal defects in metal materials.

Adults Ischium Age Estimation Based on Deep Learning and 3D CT Reconstruction.

OBJECTIVES: To develop a deep learning model for automated age estimation based on 3D CT reconstructed images of Han population in western China, and evaluate its feasibility and reliability. METHODS: The retrospective pelvic CT imaging data of 1 200 samples (600 males and 600 females) aged 20.0 to 80.0 years in western China were collected and reconstructed into 3D virtual bone models. The images of the ischial tuberosity feature region were extracted to create sex-specific and left/right site-specific sample libraries. Using the ResNet34 model, 500 samples of different sexes were randomly selected as training and verification set, the remaining samples were used as testing set. Initialization and transfer learning were used to train images that distinguish sex and left/right site. Mean absolute error (MAE) and root mean square error (RMSE) were used as primary indicators to evaluate the model. RESULTS: Prediction results varied between sexes, with bilateral models outperformed left/right unilateral ones, and transfer learning models showed superior performance over initial models. In the prediction results of bilateral transfer learning models, the male MAE was 7.74 years and RMSE was 9.73 years, the female MAE was 6.27 years and RMSE was 7.82 years, and the mixed sexes MAE was 6.64 years and RMSE was 8.43 years. CONCLUSIONS: The skeletal age estimation model, utilizing ischial tuberosity images of Han population in western China and employing the ResNet34 combined with transfer learning, can effectively estimate adult ischium age.

Volume electron microscopy for genetically and molecularly defined neural circuits.

The brain networks responsible for adaptive behavioral changes are based on the physical connections between neurons. Light and electron microscopy have long been used to study neural projections and the physical connections between neurons. Volume electron microscopy has recently expanded its scale of analysis due to methodological advances, resulting in complete wiring maps of neurites in a large volume of brain tissues and even entire nervous systems in a growing number of species. However, structural approaches frequently suffer from inherent limitations in which elements in images are identified solely by morphological criteria. Recently, an increasing number of tools and technologies have been developed to characterize cells and cellular components in the context of molecules and gene expression. These advancements include newly developed probes for visualization in electron microscopic images as well as correlative integration methods for the same elements across multiple microscopic modalities. Such approaches advance our understanding of interactions between specific neurons and circuits and may help to elucidate novel aspects of the basal ganglia network involving dopamine neurons. These advancements are expected to reveal mechanisms for processing adaptive changes in specific neural circuits that modulate brain functions.

Construction and Evaluation of an AI-based CBCT Resolution Optimization Technique for Extracted Teeth.

INTRODUCTION: In dental clinical practice, cone-beam computed tomography (CBCT) is commonly used to assist practitioners to recognize the complex morphology of root canal systems; however, because of its resolution limitations, certain small anatomical structures still cannot be accurately recognized on CBCT. The purpose of this study was to perform image super-resolution (SR) processing on CBCT images of extracted human teeth with the help of a deep learning model, and to compare the differences among CBCT, super-resolution computed tomography (SRCT), and micro-computed tomography (Micro-CT) images through three-dimensional reconstruction. METHODS: The deep learning model (Basicvsr++) was selected and modified. The dataset consisted of 171 extracted teeth that met inclusion criteria, with 40 maxillary first molars as the training set and 40 maxillary first molars as well as 91 teeth from other tooth positions as the external test set. The corresponding CBCT, SRCT, and Micro-CT images of each tooth in test sets were reconstructed using Mimics Research 17.0, and the root canal recognition rates in the 3 groups were recorded. The following parameters were measured: volume of hard tissue (V1), volume of pulp chamber and root canal system (V2), length of visible root canals under orifice (VL-X, where X represents the specific root canal), and intersection angle between coronal axis of canal and long axis of tooth (∠X, where X represents the specific root canal). Data were statistically analyzed between CBCT and SRCT images using paired sample t-test and Wilcoxon test analysis, with the measurement from Micro-CT images as the gold standard. RESULTS: Images from all tested teeth were successfully processed with the SR program. In 4-canal maxillary first molar, identification of MB2 was 72% (18/25) in CBCT group, 92% (23/25) in SRCT group, and 100% (25/25) in Micro-CT group. The difference of hard tissue volume between SRCT and Micro-CT was significantly smaller than that between CBCT and Micro-CT in all tested teeth except 4-canal mandibular first molar (P < .05). Similar results were obtained in volume of pulp chamber and root canal system in all tested teeth (P < .05). As for length of visible root canals under orifice, the difference between SRCT and Micro-CT was significantly smaller than that between CBCT and Micro-CT (P < .05) in most root canals. CONCLUSIONS: The deep learning model developed in this study helps to optimize the root canal morphology of extracted teeth in CBCT. And it may be helpful for the identification of MB2 in the maxillary first molar.

Fully Automated Construction of Three-dimensional Finite Element Simulations from Optical Coherence Tomography.

Despite recent advances in diagnosis and treatment, atherosclerotic coronary artery diseases remain a leading cause of death worldwide. Various imaging modalities and metrics can detect lesions and predict patients at risk; however, identifying unstable lesions is still difficult. Current techniques cannot fully capture the complex morphology-modulated mechanical responses that affect plaque stability, leading to catastrophic failure and mute the benefit of device and drug interventions. Finite Element (FE) simulations utilizing intravascular imaging OCT (Optical Coherence Tomography) are effective in defining physiological stress distributions. However, creating 3D FE simulations of coronary arteries from OCT images is challenging to fully automate given OCT frame sparsity, limited material contrast, and restricted penetration depth. To address such limitations, we developed an algorithmic approach to automatically produce 3D FE-ready digital twins from labeled OCT images. The 3D models are anatomically faithful and recapitulate mechanically relevant tissue lesion components, automatically producing morphologies structurally similar to manually constructed models whilst including more minute details. A mesh convergence study highlighted the ability to reach stress and strain convergence with average errors of just 5.9% and 1.6% respectively in comparison to FE models with approximately twice the number of elements in areas of refinement. Such an automated procedure will enable analysis of large clinical cohorts at a previously unattainable scale and opens the possibility for in-silico methods for patient specific diagnoses and treatment planning for coronary artery disease.

Evaluation of the Reproducibility of Auricular Subunit Markers Based on Three-Dimensional Computed Tomography.

BACKGROUND: As a facial feature, the auricle plays an important role in the integrity and aesthetics of the whole face. Auricular subunits are associated with patient satisfaction in auricular reconstruction, but there are few studies on auricular subunits. We want to evaluate the reproducibility of auricular subunits by measuring the coordinates of the marker points of auricular subunits, accordingly provide a reference for the improvement of auricular reconstruction and the aesthetics of auricular injection. METHODS: Mimics 19.0 was used to carry out three-dimensional (3D) reconstruction of the computed tomography (CT) scan data of patients' brains; measure the three-dimensional coordinates of the 13 auricular subunit markers, the morphological auricle length and width, and the physiological auricle length and width; and analyze the reproducibility as well as the differences between group. RESULTS: Reproducibility of auricle subunit markers: There are 1124 (58.82%) high reproducibility, 580 (30.35%) moderate reproducibility, and 207 (10.83%) low reproducibility. The superior tragus notch, tragus, and antitragus had the highest reproducibility. There was no significant difference between the groups in the marking points on the helix, and there were no statistically significant differences in the measurement values of the auricles on the two sides. The physiological ear length and width and the morphological ear length of males were larger than those of females. These showed significant differences between the age groups. CONCLUSION: Most auricular subunit markers have high reproducibility. The subunits with higher reproducibility are the structures that need to be optimized during auricle reconstruction surgery or auricle injection in the future. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Heterotopic twin pregnancy in unicornuate uterus and non-communicating rudimentary horn with survival of both fetuses: Magnetic resonance imaging and 3D reconstructions findings.

We reported a case of heterotopic twin pregnancy in a unicornuate uterus with a non-communicating rudimentary horn with survival of both fetuses. The diagnosis was made late at 28 weeks of gestation, with suspicion raised by ultrasound and confirmed by magnetic resonance imaging (MRI). During hospitalization, obstetric ultrasound with color Doppler was performed every 2 days to assess fetal well-being and myometrial thickness, which was determined by measurements of the uterine wall at the accessory horn. Elective cesarean section was performed at 33 + 5 weeks of gestation. Delivery started with the fetus in the rudimentary horn, with subsequent extraction of the fetus in the unicornate uterus. Three-dimensional virtual reconstruction allowed a spatial view of the both uterus and fetuses with better understanding of the obstetrical condition by the parents and interactive discussion by the multidisciplinary medical team.

Transforaminal posterior lumbar interbody fusion microscopic safe operating area: a three-dimensional model study based on computed tomography imaging.

BACKGROUND: Endoscopic spine lumbar interbody fusion (Endo-LIF) is well-regarded within the academic community. However, it presents challenges such as intraoperative disorientation, high rates of nerve damage, a steep learning curve, and prolonged surgical times, often occurring during the creation of the operative channel. Furthermore, the undefined safe operational zones under endoscopy continue to pose risks to surgical safety. We aimed to analyse the anatomical data of Kambin's triangle via CT imaging to define the parameters of the safe operating area for transforaminal posterior lumbar interbody fusion (TPLIF), providing crucial insights for clinical practice. METHODS: We selected the L4-L5 intervertebral space. Using three-dimensional (3D), we identified Kambin's triangle and the endocircle within it, and recorded the position of point 'J' on the adjacent facet joint as the centre 'O' of the circle shifts by angle 'ß.' The diameter of the inscribed circle 'd,' the abduction angle 'ß,' and the distances 'L1' and 'L2' were measured from the trephine's edge to the exiting and traversing nerve roots, respectively. RESULTS: Using a trephine with a diameter of 8 mm in TPLIF has a significant safety distance. The safe operating area under the TPLIF microscope was also clarified. CONCLUSIONS: Through CT imaging research, combined with 3D simulation, we identified the anatomical data of the L4-L5 segment Kambin's triangle, to clarify the safe operation area under TPLIF. We propose a simple and easy positioning method and provide a novel surgical technique to establish working channels faster and reduce nerve damage rates. At the same time, according to this method, the Kambin's triangle anatomical data of the patient's lumbar spine diseased segments can be measured through CT 3D reconstruction of the lumbar spine, and individualised preoperative design can be conducted to select the appropriate specifications of visible trephine and supporting tools. This may effectively reduce the learning curve, shorten the time operation time, and improve surgical safety.

Three-Dimensional Reconstruction Computed Tomography in Thoracoscopic Segmentectomy: A Randomized Controlled Trial.

OBJECTIVES: Thoracoscopic segmentectomy is the recommended treatment option for small peripheral pulmonary nodules. To assess the ability of preoperative 3D reconstruction CT to shorten the operative time and improve perioperative outcomes in thoracoscopic segmentectomy compared with standard chest CT, we conducted this randomized controlled trial. METHODS: The DRIVATS study was a multicentre, randomized controlled trial conducted in three hospitals between July 2019 and November 2023. Patients with small peripheral pulmonary nodules not reaching segments borders were randomized in a 1:1 ratio to receive either 3D reconstruction CT or standard chest CT before thoracoscopic segmentectomy. The primary end-point was operative time. The secondary end-points included incidence of postoperative complications, intraoperative blood loss and operative accident event. RESULTS: A total of 191 patients were enrolled in this study: 95 in the 3D reconstruction CT group and 96 in the standard chest CT group. All patients underwent thoracoscopic segmentectomy except for one patient in the standard chest CT group who received a wedge resection. There is no significant difference in operative time between the 3D reconstruction CT group (median, 100 min [IQR, 85-120]) and the standard chest CT group (median, 100 min [IQR, 81-140]) (P = 0.82). Only one intraoperative complication occurred in the standard chest CT group. No significant difference was observed in the incidence of postoperative complications between the two groups (P = 0.52). Other perioperative outcomes were also similar. CONCLUSIONS: In patients with small peripheral pulmonary nodules not reaching segments borders, the use of 3D reconstruction CT in thoracoscopic segmentectomy was feasible, but it did not result in significant differences in operative time or perioperative outcomes compared to standard chest CT.

Freehand 3D Ultrasound Imaging Based on Probe-mounted Vision and IMU System.

OBJECTIVES: Freehand three-dimensional (3D) ultrasound (US) is of great significance for clinical diagnosis and treatment, it is often achieved with the aid of external devices (optical and/or electromagnetic, etc.) that monitor the location and orientation of the US probe. However, this external monitoring is often impacted by imaging environment such as optical occlusions and/or electromagnetic (EM) interference. METHODS: To address the above issues, we integrated a binocular camera and an inertial measurement unit (IMU) on a US probe. Subsequently, we built a tight coupling model utilizing the unscented Kalman algorithm based on Lie groups (UKF-LG), combining vision and inertial information to infer the probe's movement, through which the position and orientation of the US image frame are calculated. Finally, the volume data was reconstructed with the voxel-based hole-filling method. RESULTS: The experiments including calibration experiments, tracking performance evaluation, phantom scans, and real scenarios scans have been conducted. The results show that the proposed system achieved the accumulated frame position error of 3.78 mm and the orientation error of 0.36° and reconstructed 3D US images with high quality in both phantom and real scenarios. CONCLUSIONS: The proposed method has been demonstrated to enhance the robustness and effectiveness of freehand 3D US. Follow-up research will focus on improving the accuracy and stability of multi-sensor fusion to make the system more practical in clinical environments.

Three-dimensional CT reconstruction-guided percutaneous balloon compression for trigeminal neuralgia.

OBJECTIVE: To study the value of three-dimensional CT (3D-CT) reconstruction by comparing the surgical effects of C-arm and 3D-CT in the treatment of trigeminal neuralgia (TN) by percutaneous balloon compression (PBC). METHODS: A total of 136 patients were included from May 2018 to February 2019. Among them, 65 patients underwent PBC treatment with 3D-CT and others with C-arm. During 3D-CT-guided operation, 3D-CT reconstruction software was used to analyze and measure the distances from the internal orifice of Foramen ovale (FO-I) and the external orifice of Foramen ovale (FO-E) to the top of the balloon (BT) and the petrous bone ridge (PR). The data, including the angle between the puncture needle direction and the zygomatic arch, petrous bone ridge, and slope, were used to assist the puncture and balloon plasty. Postoperative follow-up for more than five years was performed to evaluate the efficacy and pain recurrence. RESULTS: The distance from FO-E to PR was (2.10 ± 0.16)cm, the average distance from FO-I to BT was (2.39 ± 0.07)cm, and the average angles between the puncture needle and zygomatic arch, slope, and petrous bone ridge were (56.19 ± 5.59)°, (69.12 ± 6.92)°, and (104.49 ± 6.46)°, respectively. One (1.5 %) patient in the 3D-CT group and three (4.2 %) patients in the C-arm group failed to receive PBC treatment because of failure of FO puncture (P = 0.032).In terms of postoperative pain improvement, 3D-CT group achieved better results than the C-arm group (P = 0.043). There were no significant differences in the rates of major complications and short-term recurrence (P = 0.926) between the two groups after surgery, but the five-year recurrence rate in the 3D-CT group was lower than that in the C-arm group (P = 0.032). CONCLUSION: By guiding the angle and depth of puncture, the intraoperative application of 3D-CT reconstruction technology can improve the accuracy of foramen ovale puncture and alleviate postoperative pain, and also maintain long-term postoperative pain relief, which can be used as a potentially better guidance method to improve the surgical efficacy of PBC.

Evaluating the use of three-dimensional reconstruction visualization technology for precise laparoscopic resection in gastroesophageal junction cancer.

BACKGROUND: Laparoscopic gastrectomy for esophagogastric junction (EGJ) carcinoma enables the removal of the carcinoma at the junction between the stomach and esophagus while preserving the gastric function, thereby providing patients with better treatment outcomes and quality of life. Nonetheless, this surgical technique also presents some challenges and limitations. Therefore, three-dimensional reconstruction visualization technology (3D RVT) has been introduced into the procedure, providing doctors with more comprehensive and intuitive anatomical information that helps with surgical planning, navigation, and outcome evaluation. AIM: To discuss the application and advantages of 3D RVT in precise laparoscopic resection of EGJ carcinomas. METHODS: Data were obtained from the electronic or paper-based medical records at The First Affiliated Hospital of Hebei North University from January 2020 to June 2022. A total of 120 patients diagnosed with EGJ carcinoma were included in the study. Of these, 68 underwent laparoscopic resection after computed tomography (CT)-enhanced scanning and were categorized into the 2D group, whereas 52 underwent laparoscopic resection after CT-enhanced scanning and 3D RVT and were categorized into the 3D group. This study had two outcome measures: the deviation between tumor-related factors (such as maximum tumor diameter and infiltration length) in 3D RVT and clinical reality, and surgical outcome indicators (such as operative time, intraoperative blood loss, number of lymph node dissections, R0 resection rate, postoperative hospital stay, postoperative gas discharge time, drainage tube removal time, and related complications) between the 2D and 3D groups. RESULTS: Among patients included in the 3D group, 27 had a maximum tumor diameter of less than 3 cm, whereas 25 had a diameter of 3 cm or more. In actual surgical observations, 24 had a diameter of less than 3 cm, whereas 28 had a diameter of 3 cm or more. The findings were consistent between the two methods (χ2 = 0.346, P = 0.556), with a kappa consistency coefficient of 0.808. With respect to infiltration length, in the 3D group, 23 patients had a length of less than 5 cm, whereas 29 had a length of 5 cm or more. In actual surgical observations, 20 cases had a length of less than 5 cm, whereas 32 had a length of 5 cm or more. The findings were consistent between the two methods (χ2 = 0.357, P = 0.550), with a kappa consistency coefficient of 0.486. Pearson correlation analysis showed that the maximum tumor diameter and infiltration length measured using 3D RVT were positively correlated with clinical observations during surgery (r = 0.814 and 0.490, both P < 0.05). The 3D group had a shorter operative time (157.02 ± 8.38 vs 183.16 ± 23.87), less intraoperative blood loss (83.65 ± 14.22 vs 110.94 ± 22.05), and higher number of lymph node dissections (28.98 ± 2.82 vs 23.56 ± 2.77) and R0 resection rate (80.77% vs 61.64%) than the 2D group. Furthermore, the 3D group had shorter hospital stay [8 (8, 9) vs 13 (14, 16)], time to gas passage [3 (3, 4) vs 4 (5, 5)], and drainage tube removal time [4 (4, 5) vs 6 (6, 7)] than the 2D group. The complication rate was lower in the 3D group (11.54%) than in the 2D group (26.47%) (χ2 = 4.106, P < 0.05). CONCLUSION: Using 3D RVT, doctors can gain a more comprehensive and intuitive understanding of the anatomy and related lesions of EGJ carcinomas, thus enabling more accurate surgical planning.

Study on sex differences and potential clinical value of three-dimensional computerized tomography pelvimetry in rectal cancer patients.

BACKGROUND: Laparoscopic rectal cancer radical surgery is a complex procedure affected by various factors. However, the existing literature lacks standardized parameters for the pelvic region and soft tissues, which hampers the establishment of consistent conclusions. AIM: To comprehensively assess 16 pelvic and 7 soft tissue parameters through computerized tomography (CT)-based three-dimensional (3D) reconstruction, providing a strong theoretical basis to address challenges in laparoscopic rectal cancer radical surgery. METHODS: We analyzed data from 218 patients who underwent radical laparoscopic surgery for rectal cancer, and utilized CT data for 3D pelvic reconstruction. Specific anatomical points were carefully marked and measured using advanced 3D modeling software. To analyze the pelvic and soft tissue parameters, we employed statistical methods including paired sample t-tests, Wilcoxon rank-sum tests, and correlation analysis. RESULTS: The investigation highlighted significant sex disparities in 14 pelvic bone parameters and 3 soft tissue parameters. Males demonstrated larger measurements in pelvic depth and overall curvature, smaller measurements in pelvic width, a larger mesorectal fat area, and a larger anterior-posterior abdominal diameter. By contrast, females exhibited wider pelvises, shallower depth, smaller overall curvature, and an increased amount of subcutaneous fat tissue. However, there were no significant sex differences observed in certain parameters such as sacral curvature height, superior pubococcygeal diameter, rectal area, visceral fat area, waist circumference, and transverse abdominal diameter. CONCLUSION: The reconstruction of 3D CT data enabled accurate pelvic measurements, revealing significant sex differences in both pelvic and soft tissue parameters. This study design offer potential in predicting surgical difficulties and creating personalized surgical plans for male rectal cancer patients with a potentially "difficult pelvis", ultimately improving surgical outcomes. Further research and utilization of these parameters could lead to enhanced surgical methods and patient care in laparoscopic rectal cancer radical surgery.

Three-dimensional reconstruction of King Henri IV's paranasal sinuses and mastoid cells.

PURPOSE: The preserved head of King Henri IV of France (life 1553-1610, reign 1589-1610) has survived to the present day thanks to high-quality embalming and favorable conservation conditions. The aim of this study was to examine Henry IV's upper resonant cavities and mastoids using an original and innovative forensic three-dimensional segmentation method. METHODS: The paranasal sinuses and mastoid cells of King Henri IV of France were studied by cross-referencing available biographical information with clinical and flexible endoscopic examination and computed tomography (CT-scan) imaging. The paranasal sinuses and mastoid cells were delineated and their volumes were assessed using ITK-SNAP 4.0 software (open-source). Graphical representations were created using Fusion 360® (Autodesk Inc., San Rafael, CA, USA) and MeshMixer® (Autodesk Inc., San Rafael, CA, USA). RESULTS: Paranasal sinus tomodensitometry revealed abnormalities in shape and number. Henri IV of France suffered from sinus aplasia. Neither the left sphenoid nor left frontal sinus contrasted sharply, and a remarkable pneumatization of the right clinoid processes extended throughout the height of the right pterygoid process. The total volumes of Henri IV's mastoid air-cells were estimated at 27 and 26 mL, respectively, for the right and left sides, exceeding the normal mean and the maximum of modern subjects by a wide margin. No sign of chronic ear or sinus condition was found. CONCLUSIONS: An innovative method has been developed in forensic medicine to establish hypotheses about the growth and respiratory conditions of the face.

Effect of grayscale threshold on X-ray computed tomography reconstruction of gas diffusion layers in polymer electrolyte membrane fuel cells.

In X-ray computed tomography (CT) reconstructions of gas diffusion layers (GDLs), grayscale threshold selection is a critical issue. Although various selection methods exist, they all have their own drawbacks. This study investigates the influence of grayscale threshold on GDL properties and compares Otsu and porosity-adaptive thresholds. We utilized X-ray CT to reconstruct a Toray carbon paper sample (TGP-H-060) at a resolution of 2 µm. Using reconstructed 3D models generated under different grayscale thresholds, we performed structural analysis, computational fluid dynamics simulation, and compression simulation. We subsequently calculated porosity, tortuosity, permeability, and macroscopic stress-strain relationships, quantitatively analyzing the sensitivity of these parameters to the change of grayscale threshold. The results indicated that small change in the grayscale threshold can significantly impact the transport and mechanical properties of reconstructed GDLs. The difference between Otsu and porosity-adaptive thresholds is notable, and the porosity-adaptive threshold appears to be less accurate than the Otsu threshold.

Different anatomical variations in the anterior segment of the right upper lung.

During a routine physical examination three years ago, a 47-year-old woman received a diagnosis of a nodule in her right upper lung. Since then, she has been regularly attending outpatient clinic appointments for follow-up. Over time, the nodule has shown gradual growth, leading to a suspicion of lung cancer. Through the use of enhanced CT imaging, a three-dimensional reconstruction was performed to examine the bronchi and blood vessels in the patient's chest. This reconstruction revealed several variations in the anatomy of the anterior segment of the right upper lobe. Specifically, the anterior segmental bronchus (B3) was found to have originated from the right middle lung bronchus. Additionally, the medial subsegmental artery of the anterior segmental artery (A3b) and the medial segmental artery (A5) were observed to share a common trunk. As for the lateral subsegmental artery of the anterior segmental artery (A3a), it was found to have originated from the right inferior pulmonary trunk. Furthermore, the apical subsegmental artery of the apical segmental artery (A1a) and the posterior segmental artery (A2) were found to have a shared trunk.