The virtual dissecting room: Creating highly detailed anatomy models for educational purposes.

INTRODUCTION: Virtual 3D models are powerful tools for teaching anatomy. At the present day, there are a lot of different digital anatomy models, most of these commercial applications are based on a 3D model of a human body reconstructed from images with a 1mm intervals. The use of even smaller intervals may result in more details and more realistic appearances of 3D anatomy models. The aim of this study was to create a realistic and highly detailed 3D model of the hand and wrist based on small interval cross-sectional images, suitable for undergraduate and postgraduate teaching purposes with the possibility to perform a virtual dissection in an educational application. METHODS: In 115 transverse cross-sections from a human hand and wrist, segmentation was done by manually delineating 90 different structures. With the use of Amira the segments were imported and a surface model/polygon model was created, followed by smoothening of the surfaces in Mudbox. In 3D Coat software the smoothed polygon models were automatically retopologied into a quadrilaterals formation and a UV map was added. In Mudbox, the textures from 90 structures were depicted in a realistic way by using photos from real tissue and afterwards height maps, gloss and specular maps were created to add more level of detail and realistic lightning on every structure. Unity was used to build a new software program that would support all the extra map features together with a preferred user interface. CONCLUSION: A 3D hand model has been created, containing 100 structures (90 at start and 10 extra structures added along the way). The model can be used interactively by changing the transparency, manipulating single or grouped structures and thereby simulating a virtual dissection. This model can be used for a variety of teaching purposes, ranging from undergraduate medical students to residents of hand surgery. Studying the hand and wrist anatomy using this model is cost-effective and not hampered by the limited access to real dissecting facilities.

Architecture of the Corpus Spongiosum: An Anatomical Study.

PURPOSE: Urethral reconstruction is performed for urethral stricture or hypospadias correction. Research on urethral tissue engineering is increasing. Because the corpus spongiosum is important to support the urethra, urethral tissue engineering should ideally be combined with reconstruction of a corpus spongiosum. We describe a method to visualize and measure the architecture of the corpus spongiosum, which is needed for scaffold design. MATERIALS AND METHODS: The penis was dissected from 2 unembalmed male cadavers. One penis was flaccid and the other was erect, as induced by saline infusion. Both were frozen in ice. At 6 sites sections were obtained in the transverse and frontal directions. After digitalizing the stained sections the images were edited, area measurements were taken and a 3-dimensional reconstruction was made. RESULTS: In transverse sections the mean area of the vascular lumen was 60% and 77% in the flaccid and the erect corpus spongiosum, and in frontal sections it was 53% and 74%, respectively. This indicated a 129% transverse increase and a 140% longitudinal increase in erection. Section sites did not essentially differ except in the glans penis. Frontal sections showed larger vascular cavities and more incomplete septae than transverse sections. CONCLUSIONS: This study provides what is to our knowledge novel information on corpus spongiosum architecture, which is relevant for scaffold design in tissue engineering. The study protocol can be used in future research with a larger number of specimens and more extensive analyses.

Support for using a three-dimensional anatomy application over anatomical atlases in a randomized comparison.

To investigate to what extent the use of a three-dimensional (3D) anatomy computer application can improve the acquisition of anatomical knowledge compared with anatomical atlases, junior and advanced medical students participated in an experiment. Participants were asked to answer anatomical questions with the use of a 3D anatomy application (developed at the University Medical Center in Utrecht, the Netherlands) or anatomy atlases. Every student had to complete two assignments, either with an atlas or with the 3D anatomy application. One assignment consisted of 20 questions about the anatomy of the hand, the other one had 20 questions about the anatomy of the foot. The scores on the assignments and time to complete the assignments were registered and investigated. A total of 76 students participated. Students scored significantly higher and were significantly faster when they used the 3D anatomy application. Junior medical students were significantly faster than advanced medical students and particularly, advanced students who worked with an atlas needed most time. These results suggest that the 3D anatomy application is more effective as a studying tool, when compared to the use of paper atlases, for both junior and advanced medical students. The difference in time could indicate an influence of the increased number of mental steps it takes to convert two-dimensional atlas images to a 3D mental representation compared to using the 3D anatomy application, although practical issues explaining this cannot be ruled out. Future studies should establish whether the application leads to better learning/retention and to more time-efficient studying.

Comparing the critical features of e-applications for three-dimensional anatomy education.

Anatomical e-applications are increasingly being created and used in medical education and health care for the purpose of gaining anatomical knowledge. Research has established their superiority over 2D methods in the acquisition of spatial anatomy knowledge. Many different anatomy e-applications have been designed, but a comparative review is still lacking. We aimed to create an overview for comparing the features of anatomy e-applications in order to offer guidance in selecting a suitable anatomy e-application. A systematic search was conducted. Data were retrieved from the 3D model designs (realism), software aspects and program functionality. The non-commercial e-applications focused on small body regions and received an average score of 3.04 (range 1-5) for model realism. Their average score on program functionality was 8.8 (range 0-14). The commercial e-applications covered the entire human body and received an average score of 2.85 (range 1-5) for model realism. Their average score on program functionality was 10.4 (range 0-14). Non-commercial anatomy e-applications received higher scores on realism and facilities like performing a virtual dissection, while the commercial anatomy e-applications offer a much wider range of anatomical structures available and they showed higher scores on program functionality. These scores gave good insight of the e-applications' possibilities, and may help future users to make an informed choice among the large number of available e-applications.