Donor bile duct evaluation with magnetic resonance cholangiography in living-donor liver transplantation: a novel anatomical classification for predicting surgical techniques.

PURPOSE: To propose a novel, inclusive classification that facilitates the selection of the appropriate donor and surgical technique in living-donor liver transplantation (LDLT). METHODS: The magnetic resonance cholangiography examinations of 201 healthy liver donors were retrospectively evaluated. The study group was classified according to the proposed classification. The findings were compared with the surgical technique used in 93 patients who underwent transplantation. The Couinaud, Huang, Karakas, Choi, and Ohkubo classifications were also applied to all cases. RESULTS: There were 118 right-lobe donors (58.7%) and 83 left-lateral-segment donors (41.3%). Fifty-six (28.8%) of the cases were classified as type 1, 136 (67.7%) as type 2, and 7 (3.5%) as type 3 in the proposed classification; all cases could be classified. The number of individuals able to become liver donors was 93. A total of 36 cases were type 1, 56 were type 2, and 1 was type 3. Of the type 1 donors, 83% required single anastomosis during transplantation, whereas six patients classified as type 1 required two anastomoses, all of which were caused by technical challenges during resection. Moreover, 51.8% of the cases classified as type 2 required additional anastomosis during transplantation. The type 3 patient required three anastomoses. The type 1 and type 2 donors required a different number of anastomoses (P < 0.001). CONCLUSION: The proposed classification in this study includes all anatomical variations. This inclusive classification accurately predicts the surgical technique for LDLT.

A Model for Medical Students' Behavioral Intention to Use Mobile Learning.

The use of mobile devices that have high technical capabilities has increased in the last years. These devices are appropriate instructional tools reflecting the trends in modern education by providing instant access to information that is used with mobile learning purposes. As is in many areas of education, m-learning has been becoming widespread in medical education. Therefore, medical students' readiness for m-learning is highly important. This study aims to investigate how medical students' beliefs influence their behavioral intention to use mobile devices for learning purposes. The 376 medical students (222 juniors, 154 sophomores; aged between 18 and 24 years; 214 males, 162 females) participated in this study. All participants had mobile devices. Data were collected through a survey. Structural equation modeling was used to analyze the findings. The proposed model, which is created based on the theory of planned behavior, was tested in the study. Based on the findings, the medical students' perceived ease of use, perceived usefulness, learning autonomy, intention to use, perceived self-efficacy toward mobile devices, and m-learning are found to be high level. However, according to medical students, instructors' readiness to apply m-learning has been found to be low level. The findings showed that the proposed model explains medical students' behavioral intention to use m-learning reasonably well. The behavioral intention is explained with a variance of 76% in the model. Subjective norm is the main indicator of behavioral intention, followed by perceived behavioral control and attitude. The proposed model in the study could be useful to design m-learning applications, environments, and implementation plans effectively in medical education.

Morphometric Evaluation of Craniocervical Junction by Magnetic Resonance Imaging Method.

PURPOSE: Morphometric evaluation of the craniocervical region using magnetic resonance imaging method in humans and determination of the reference values that could be used in various clinics were the aims of this study. MATERIALS AND METHODS: In our study, 306 (95 males and 211 females) individuals who met the necessary criteria for anatomical structure were included and taken measurements afterward. Sagittal T1- and T2-weighted images were determined as a section thickness of 3 mm, an interval of 10 mm, a matrix of 352 × 224, a field of view of 170-240 mm, and a number of excitations of 4. Measurements of anatomical structures in the craniocervical region were taken via these images. RESULTS: Statistically significant differences were found among the findings of male and female individuals such as height of dens axis, anteroposterior distance of the dens axis (APDDA), anterosuperior distance of the dens axis (ASDDA), sagittal diameter of the foramen magnum (SDFM), total cervical vertebra length (TCVL), distance of spatium retropharyngeum, Pavlov ratio, and the ratio between sagittal diameter of canalis vertebralis (SDCV) to the APDDA. Dens axis height showed a positive correlation with ASDDA and TCVL, and a negative correlation was found between the APDDA and the spatium retropharyngeum. CONCLUSION: Age- and sex-related changes in the measurements of anatomical regions reveal that an increase and a decrease in the various parameters reveal that these are the normal changes presumably determined by the functional and physical demands varying on the columna vertebralis.

Learning anatomy via mobile augmented reality: Effects on achievement and cognitive load.

Augmented reality (AR), a new generation of technology, has attracted the attention of educators in recent years. In this study, a MagicBook was developed for a neuroanatomy topic by using mobile augmented reality (mAR) technology. This technology integrates virtual learning objects into the real world and allow users to interact with the environment using mobile devices. The purpose of this study was to determine the effects of learning anatomy via mAR on medical students' academic achievement and cognitive load. The mixed method was applied in the study. The random sample consisted of 70 second-year undergraduate medical students: 34 in an experimental group and 36 in a control group. Academic achievement test and cognitive load scale were used as data collection tool. A one-way MANOVA test was used for analysis. The experimental group, which used mAR applications, reported higher achievement and lower cognitive load. The use of mAR applications in anatomy education contributed to the formation of an effective and productive learning environment. Student cognitive load decreased as abstract information became concrete in printed books via multimedia materials in mAR applications. Additionally, students were able to access the materials in the MagicBook anytime and anywhere they wanted. The mobile learning approach helped students learn better by exerting less cognitive effort. Moreover, the sensory experience and real time interaction with environment may provide learning satisfaction and enable students to structure their knowledge to complete the learning tasks. Anat Sci Educ 9: 411-421. © 2016 American Association of Anatomists.

An unusual anatomic variation of the jugular foramen with doubled posterior condylar canal / Una variación anatómica inusual del foramen yugular con canal condilar posterior duplicado

A case of unusual anatomical variation of the jugular foramen (JF) with doubled posterior condylar canal (PCC) is reported. According to the presence of bridging, the JF can be defined as Type I (one septation, two compartments) on the right side and Type IV (three septations, four compartments) on the left side. The dome of the jugular fossa is present on the right, absent on the left. The jugular foramen shows a canal-like structure with an external and an internal opening. The lengths of the longest and widest axes of the JFs are measured as 21.93 x 16.56 mm on the right and 16.75 x 15.14 mm on the left side. The right JF is larger. The PCC is doubled on the right side and there is only one on the left side. It is essential not only to know compartments per se but also to know the structures passing through the compartments, in order to achieve desired surgical outcomes and avoid complications.

Es reportado el caso de una inusual variación anatómica del foramen yugular (FY), con el canal condilar posterior duplicado (CCP). De acuerdo con la presencia de los puentes, el FY se puede definir como Tipo I (una tabicación, dos compartimientos) en el lado derecho y Tipo IV (tres tabiques, cuatro compartimientos) en el lado izquierdo. El domo de la fosa yugular está presente en el lado derecho, y ausente en el izquierdo. El foramen yugular mostró una estructura igual a un canal con una apertura externa y otra interna. Las longitudes de los ejes más largos y anchos de la FY fueron 21,93x16,56mm al lado derecho y 16,75x15,14mm al lado izquierdo. El FY derecho fue más grande. El CCP se observó duplicado en el lado derecho y único en el lado izquierdo. Es esencial no sólo conocer los compartimientos en sí, sino también las estructuras que pasan a través de los compartimientos con el fin de lograr los resultados deseados y evitar las complicaciones quirúrgicas.

The reproduction accuracy for stereolithographic model of the thyroid gland derived from the visible human dataset.

OBJECTIVE: To investigate reproduction accuracy of the rapid prototyping technique by comparing 3-dimensional computer-aided design (CAD) (virtual) model with stereolithographic (solid) replica of the thyroid gland. METHODS: The Visible Human Dataset was used as the input imaging data. The Surfdriver software package was applied on these images to reconstruct the thyroid gland as 3-dimensional Data Exchange File (DXF) models. These models were post-processed in Cinema 4D and 3D-Doctor software for Virtual Reality Modeling Language (VRML) and Standard Triangulation Language (STL) formats. Stereolithographic replica was manufactured in the rapid prototyping machine using STL format. This study was conducted between June 1-30, 2008 at the Department of Anatomy, Hacettepe University, Ankara, Turkey. An excellent agreement was found in comparing the maximal dimensions of the CAD model of the thyroid gland and the corresponding stereolithographic model. Visual and tactile examination of the thyroid gland model allowed correct depiction of the thyroid gland anatomy. The accuracy of the stereolithographic model was attained by comparing wih the CAD model. RESULTS: Dimensional analysis showed that an average difference between the measurements on the virtual and the solid model was 0.09 mm (p=0.06), ranging from 0.07-0.92 mm. Thyroid volume and surface area were calculated to be 25393.9 mm3 and 8242.8 mm2 using 3D-Doctor software, which were agreement with those obtained from Brunn's formula. CONCLUSION: Stereolithographic biomodeling is a state-of-the-art and reliable method of visualizing anatomoclinical structures and abnormalities.

Quantitative analysis of myelinated axons of commissural fibers in the cat brain.

OBJECTIVE: There are limited data related to the number of commissural axons found in various species. Although the corpus callosum has been investigated in cat, there are no data on the number of its myelinated axons. Additionally, the number of myelinated axons of anterior, posterior and habenular commissures are not documented for the cat. Therefore, we aimed to examine the topographic distribution and regional numerical differences of myelinated axons in encephalic commissures of the cat. METHODS: This study was carried out at the Faculty of Medicine, Hacettepe University, Ankara, Turkey, from March 2003 to July 2003. The myelinated axons of the encephalic commissures of one cat were counted in this study. RESULTS: In parts of the corpus callosum, a statistically significant difference was found between rostrum and genu, rostrum and truncus, genu and truncus, genu and splenium and truncus and splenium. However, no statistically significant difference was found between rostrum and splenium. When comparing the number of myelinated axons of anterior, posterior and habenular commissures, statistically significant differences were found between anterior and habenular commissures, and between posterior and habenular commissures. No statistically significant difference was found between anterior and posterior commissures. CONCLUSION: These numerical data, evaluated by quantitative analytical statistical methods, might be useful in filling the lack of information on the mean numbers of myelinated axons of different commissures. Knowledge of the number of myelinated axons in different parts of the corpus callosum may also be very important when performing surgical procedures of the corpus callosum, such as commissurectomies.