OBJECTIVETo study digitized virtual hepatic three-dimensional reconstruction and virtual hepatic surgery.

METHODSThe whole series of hepatic images taken from the database of digitized Virtual Chinese Human Female Number 1 (VCH-F1) was employed to reconstruct a three-dimensional (3D) liver. First, studied some algorithms for registration of human liver tissue images, and then, segmented the regions of liver, vein, bile duct, and gallbladder from the images. Based on them, the 3D visualization human liver model was reconstructed. Finally, a 3D visualization demo system of liver was developed based on personal computer and Windows operation system.

RESULTSThis demo system of liver provided a graphics user interface to rotate, scale the 3D liver to observe the 3D hepatic structure, and a virtual liver simulation system of resection with primary function.

CONCLUSIONSThe study may be beneficial to the future research on digitized virtual hepatic and virtual hepatic surgery, and the 3D visualization demo system of liver may be beneficial to the research on the hepatic structure.

Anatomy, Cross-Sectional ; China ; Female ; Hepatectomy ; Humans ; Imaging, Three-Dimensional ; methods ; Liver ; anatomy & histology ; User-Computer Interface

BACKGROUND AND OBJECTIVES: The embryological development of paranasal sinuses has been revealed by previous articles although few studies have reported on the differences of paranasal sinus pneumatization according to age after adolescence. We evaluated changes in paranasal sinus pneumatization in the ages ranging from 10s to over 60s. SUBJECTS AND METHOD: A retrospective review was carried out for patients who underwent osteomeatal unit three-dimensional computed tomography from January 2008 to March 2017. Two hundred and forty patients were selected and matched for age, sex, and existence of sinusitis. The biggest cross-sectional area (CSA) of each sinus was selected from each patient, which was then corrected to the size of the face. CSA and corrected CSA (cCSA) values were used together for analysis. RESULTS: CSAs of frontal, maxillary, sphenoid sinuses gradually increased in the ages ranging in the 30s, and then significantly decreased from those in the 40s onwards. In particular, these tendencies were statistically significant in all types of sinuses between the 30s and 40s, (p<0.05), except for sphenoid sinus. When comparing men and women, menduallys were bigger in most of the sinuses and in some age groups (p<0.05). However, there were no differences in cCSAs (p>0.05). CSAs in patients with chronic sinusitis were not different from those in patients without chronic sinusitis in every sinus and all age groups (p>0.05). CONCLUSION: This study shows that older people have smaller sinuses, and sex difference and existence of sinusitis have no effect on the pneumatization of the sinuses.
Adolescent ; Anatomy, Cross-Sectional ; Female ; Humans ; Male ; Methods ; Paranasal Sinuses ; Retrospective Studies ; Sex Characteristics ; Sinusitis ; Sphenoid Sinus

BACKGROUND: Volume models made from magnetic resonance images on computed tomographs can produce horizontal, coronal, sagittal, and oblique planes that are used widely in clinics, although detailed structures cannot be identified. Existing real color volume models are mostly commercial and their production methods have not been released. The aim of this study was to distribute free of charge, real-color volume models produced from sectioned images with the production method. METHODS: The original voxel size of sectioned images was increased appropriately so that the volume model could be handled by typical personal computers. By using Dicom Browser and MRIcroGL, the sectioned images were processed to become the volume models. RESULTS: On the MRIcroGL, the resultant volume model with the voxel size of 0.5 × 0.5 × 0.5 mm3 could be displayed and freely rotated. By adjusting variables of the software, desired oblique planes could be produced instantly. With overlay function, a model of segmented structure can be overlapped to the entire volume models. The sectioned images with high quality and the segmentation data of Visible Korean enabled the identification of detailed anatomical structures on the planes. CONCLUSION: The volume models can be used by medical students and doctors for learning sectional anatomy. Other researchers can utilize the method of this study to produce volume models from their own sectioned images.
Anatomy, Cross-Sectional ; Computer Simulation ; Humans ; Imaging, Three-Dimensional ; Learning ; Methods ; Microcomputers ; Students, Medical ; Visible Human Projects

A novel technique of three-dimensional (3D) reconstruction, segmentation, display and analysis of series slices of images including microscopic wide field optical sectioning by deconvolution method, cryo-electron microscope slices by Fourier-Bessel synthesis and electron tomography (ET), and a series of computed tomography (CT) was developed to perform simultaneous measurement on the structure and function of biomedical samples. The paper presents the 3D reconstruction segmentation display and analysis results of pollen spore, chaperonin, virus, head, cervical bone, tibia and carpus. At the same time, it also puts forward some potential applications of the new technique in the biomedical realm.
Algorithms ; Anatomy, Cross-Sectional ; methods ; Artificial Intelligence ; Image Enhancement ; methods ; Image Interpretation, Computer-Assisted ; methods ; Imaging, Three-Dimensional ; methods ; Pattern Recognition, Automated ; methods ; Reproducibility of Results ; Sensitivity and Specificity

OBJECTIVETo investigate the methodology of mimic resection system on liver.

METHODSHepatic arteries, portal vein, inferior cava vein, hepatic veins and biliary ducts of liver with integrate hepatic portal were perfused with filling materials in different colors. And then the sample was embedded, frozen and slice-cut to obtain serial sectional images. After image registration and segmentation, the 3D reconstruction model which contained the liver's surface and its internal structures was constructed with MIMICS 9.0. Based on the freeform modeling system and its accessories (the software GHOST and the force-feedback equipment PHANTOM), the virtual hepatectomy system was established which could manipulate the virtual scalpel to perform optional resection on virtual liver model.

RESULTSAfter slice-cutting the cast liver, 910 serial cross-section images were obtained sharply and clearly. The 3D reconstructed liver model looked like the liver sample exactly, and could be magnified, contracted and rotated. In the virtual surgery system with good interaction, powerful immersion and great imagination, the virtual scalpel could be manipulated to perform optional resection on 3D liver model with the haptic device (PHANTOM).

CONCLUSIONSThe 3D visualized liver and the virtual hepatectomy system has been satisfactorily developed using the hepatic serial sectional images. The process of simulation operation was consistent with clinical practice.

Adult ; Anatomy, Cross-Sectional ; Hepatectomy ; methods ; Humans ; Image Processing, Computer-Assisted ; Imaging, Three-Dimensional ; Liver ; anatomy & histology ; blood supply ; surgery ; Models, Anatomic ; Models, Biological ; User-Computer Interface

Acoustic rhinometry and acoustic pharyngometry (AR/P) can quantify the upper airway condition of air draft by drawing a graph plotting the nasal cavity and pharyngeal cavity cross-sectional area. Based on CT medical images of volunteers, a 3-dimensional finite element model of upper respiratory tract was reconstructed by using the method of surface rendering. The veracity of the model was valued by comparison of the relevant areas between the model and the AR/P graph; and an AR/P was used to help improve and enrich the model. The combination of AR/ P and CT is useful in studying the medicine problem related to the anatomical structure of upper respiratory tract.
Anatomy, Cross-Sectional ; methods ; Finite Element Analysis ; Humans ; Imaging, Three-Dimensional ; methods ; Larynx ; anatomy & histology ; diagnostic imaging ; Nasal Cavity ; anatomy & histology ; diagnostic imaging ; Rhinometry, Acoustic ; methods ; Tomography, X-Ray Computed

BACKGROUNDThe injury of the triangular fibrocartilage complex (TFCC) is a common cause of ulnar-sided wrist pain. The aim of this study was to investigate if the high-resolution 3T magnetic resonance imaging (MRI) could demonstrate the detailed complex anatomy of TFCC in Chinese.

METHODSFourteen Chinese cadaveric wrists (from four men and three women; age range at death from 30 to 60 years; mean age at 46 years) and forty healthy Chinese wrists (from 20 healthy volunteers, male/female: 10/10; age range from 21 to 53 years with a mean age of 32 years) in Beijing Jishuitan Hospital from March 2014 to March 2016 were included in this study. All cadavers and volunteers had magnetic resonance (MR) examination of the wrist with coronal T1-weighted and proton density-weighted imaging with fat suppression in three planes, respectively. MR arthrography (MRAr) was performed on one of the cadaveric wrists. Subsequently, all 14 cadaveric wrists were sliced into 2 mm thick slab with band saw (six in coronal plane, four in sagittal plane, and four in axial plane). The MRI features of normal TFCC were analyzed in these specimens and forty healthy wrists.

RESULTSTriangular fibrocartilage, the ulnar collateral ligament, and the meniscal homolog could be best observed on images in coronal plane. The palmar and dorsal radioulnar ligaments were best evaluated in transverse plane. The ulnotriquetral and ulnolunate ligaments were best visualized in sagittal plane. The latter two structures and the volar and dorsal capsules were better demonstrated on MRAr.

CONCLUSIONHigh-resolution 3T MRI is capable to show the detailed complex anatomy of the TFCC and can provide valuable information for the clinical diagnosis in Chinese.

Adult ; Cross-Sectional Studies ; Female ; Humans ; Magnetic Resonance Imaging ; methods ; Male ; Middle Aged ; Triangular Fibrocartilage ; anatomy & histology ; diagnostic imaging ; Wrist ; anatomy & histology ; diagnostic imaging ; Wrist Joint ; anatomy & histology ; diagnostic imaging

BACKGROUNDRTVue spectral-domain optical coherence tomography (OCT) is a new, ultra high-speed and high-resolution instrument, potentially to measure the presence of glaucoma or its progression accurately. The objective of this study was to evaluate its reproducibility of retinal nerve fiber layer (RNFL) thickness and optic nerve head (ONH) measurements in normal and glaucoma eyes.

METHODSThis study was an observational clinical study. One eye was selected randomly from each of 89 normal individuals and 63 glaucoma patients in a range of severity. RNFL thickness and ONH were measured 3 times on the same day to determine intrasession variability. The same instrument was used by the same operator for all scans. Intrasession within-subject standard deviation (Sw), precision (1.96 x Sw), coefficient of variation (CVw, 100 x Sw/overall mean), and intraclass coefficient (ICC) were calculated to evaluate reproducibility.

RESULTSRTVue OCT demonstrated double hump patterns in the RNFL profiles. High reproducibility was observed in all ONH parameters. For normal eyes, the value of ICC ranged between 0.98 and 1.00. For eyes with different extent of glaucoma, it ranged between 0.94 and 1.00. High reproducibility was also observed in RNFL thickness measurements. The values of ICC for averaged RNFL thickness ranged between 0.95 and 1.00 in all cases. For regional parameters, it ranged from 0.94 to 0.98 for normal eyes, 0.94 to 1.00 for mild glaucoma eyes, 0.87 to 1.00 for moderate glaucoma eyes, and 0.77 to 0.97 for severe glaucoma eyes. The nasal regions of severe glaucoma appeared to be most variable, as nasal lower region and inferior nasal region had the ICC values of 0.77 and 0.87.

CONCLUSIONReproducibility of RTVue RNFL and ONH measurements was excellent in normal and glaucoma groups.

Adult ; Aged ; Cross-Sectional Studies ; Female ; Glaucoma ; pathology ; Humans ; Male ; Middle Aged ; Nerve Fibers ; Optic Disk ; anatomy & histology ; pathology ; Tomography, Optical Coherence ; methods ; Young Adult

INTRODUCTIONToday's physicians must demonstrate both professionalism and leadership skills in order to succeed in largely team-based healthcare environments. The purpose of this study was to determine if professionalism attributes, leadership style, and leadership style adaptability are associated with academic performance among first-year students early in their medical curriculum.

MATERIALS AND METHODSStudents were divided into 4-member dissection groups for the duration of the Gross and Developmental Anatomy course. Leadership responsibility was randomly assigned to a team member on a rotating basis every 5 weeks. After each 5-week block, student performance was measured by written and practical examinations, and each student assessed their leader's or their own professionalism attributes and leadership style using validated survey instruments.

RESULTSMost students demonstrated either a "selling" only (57%) or "participating" only (30%) leadership style with low to moderate leadership adaptability. "Participating" and "delegating" leadership styles have the highest average group written exam scores (89.4%, P <0.008). "Telling" only or "selling" only leaders have the lowest average group exam scores (83.5%, P <0.001). "Selling" and "participating" leaders have significantly lower average group practical exam scores than other styles (81.5%, P <0.007). Positive associations were observed between the written and practical examination scores and the leader's integrity (P = 0.003, P = 0.002) and responsibility (P <0.001, P = 0.037).

CONCLUSIONSThis study demonstrates that various situational leadership styles and aspects of professionalism are associated with written and practical examination scores in the Gross and Developmental Anatomy course. Furthermore, it demonstrates that first-year medical students are in need of leadership skill development.

Anatomy, Cross-Sectional ; education ; Curriculum ; standards ; Education, Medical ; methods ; standards ; Female ; Humans ; Leadership ; Male ; Practice Patterns, Physicians' ; Retrospective Studies ; Students, Medical

PURPOSE: To evaluate the effect of the scanning laser ophthalmoscope (SLO) guided re-test mode on short- and long-term measurement variability of peripapillary retinal nerve fiber layer (RNFL) thickness obtained by spectral domain-SLO optical coherence tomography (SD-SLO/OCT). METHODS: Seventy five healthy eyes were scanned 3 times per day (intra-session variability) by both the SLO guided re-test mode and the independent mode of SD-SLO/OCT. Subjects were scanned 3 times by both modes at visits within a 2-week interval (inter-session variability). For testing longitudinal variability, 3 separate exams were performed over 6 months by both modes. The coefficient of variation (CV), reproducibility coefficient (RC) and intraclass correlation coefficient of RNFL thickness were compared between the two modes. RESULTS: The intra-session RC and CV ranged from 5.4 to 12.9 microns and 1.76% to 5.72% when measured by independent mode and 5.4 to 12.5 microns and 1.75% to 5.58% by re-test mode, respectively. The inter-session RC and CV ranged from 5.8 to 13.3 microns and 1.89% to 5.78% by independent mode and 5.8 to 12.7 microns and 1.90% to 5.54% by re-test mode, respectively. Intra-session and inter-session variability measurements were not significantly different between the two modes. The longitudinal RC and CV ranged from 8.5 to 19.2 microns and 2.79% to 7.08% by independent mode and 7.5 to 14.4 microns and 2.33% to 6.22% by re-test mode, respectively. Longitudinal measurement variability was significantly lower when measured by the re-test mode compared to the independent mode (average, p = 0.011). CONCLUSIONS: The SLO guided re-test mode for RNFL thickness measurement in SD-SLO/OCT employing a tracking system improved long-term reproducibility by reducing variability induced by inconsistent scan circle placement.
Adult ; Algorithms ; Anatomy, Cross-Sectional ; Female ; Humans ; Male ; Nerve Fibers ; Ophthalmoscopes ; Reference Values ; Reproducibility of Results ; Retinal Ganglion Cells/*cytology ; Tomography, Optical Coherence/*methods