OBJECTIVE Cranioplasty implants should be widely available, low in cost, and customized or easy to mold during surgery. Although autologous bone remains the first choice for repair, it cannot always be used due to infection, fragmentation, bone resorption, or other causes, which led to use of synthetic alternatives. The most frequently used allogenic material for cranial reconstructions with long-term results is polymethylmethacrylate (PMMA). Three-dimensional printing technology has allowed the production of increasingly popular customized, prefabricated implants. The authors describe their method and experience with a customized PMMA prosthesis using a precise and reliable low-cost implant that can be customized at any institution with open-source or low-cost software and desktop 3D printers. METHODS A review of 22 consecutive patients undergoing CT-based, low-cost, customized PMMA cranioplasty over a 1-year period at a university teaching hospital was performed. Preoperative data included patient sex and age; CT modeling parameters, including the surface area of the implant (defect); reason for craniectomy; date(s) of injury and/or resections; the complexity of the defect; and associated comorbidities. Postoperative data included morbiditiy and complications, such as implant exposure, infection, hematoma, seroma, implant failure, and seizures; the cost of the implant; and cosmetic outcome. RESULTS Indications for the primary craniectomy were traumatic brain injury (16, 73%), tumor resection (3, 14%), infection (1, 4%), and vascular (2, 9%). The median interval between previous surgery and PMMA cranioplasty was 12 months. The operation time ranged from 90 to 150 minutes (mean 126 minutes). The average cranial defect measured 65.16 cm (range 29.31-131.06 cm). During the recovery period, there was no sign of infection, implant rejection, or wound dehiscence, and none of the implants had to be removed over a follow-up ranging from 1 to 6 months. The aesthetic appearance of all patients was significantly improved, and the implant fit was excellent. CONCLUSIONS The use of a customized PMMA was associated with excellent patient, family, and surgeon satisfaction at follow-up at a fraction of the cost associated with commercially available implants. This technique could be an attractive option to all patients undergoing cranioplasty.

Over the years we have observed that there is a very low passing rate for the Anatomy and Neuroanatomy courses in our department, and for that reason we decided to implement the use of student-learning resources. The objective of this study was to compare the results of traditional methodology with those obtained with the support of computer-assisted learning (CAL). We performed a retrospective and joint study for Anatomy and Neuroanatomy groups during the period of September 2001 to February 2003, to establish a comparison between traditional learning and traditional learning supported by CAL. In the Anatomy group, students who used the traditional method (n1 = 365) received an average final grade of 58 (SD = 14.94), while the average final grade for students who used the traditional method supported by CAL (n2 = 283) was 68 (SD = 14.56). In the Neuroanatomy group, the students who used the traditional method (n3 = 217) had an average final grade of 61 (SD = 14.51), while the students who used the traditional method supported by CAL (n4 = 134) received an average final grade of 68 (SD = 13.52). A z-test was conducted to determine the difference in averages between the two groups (alpha = 0.05), and the results showed that the averages were significantly different (P <.001). The modified traditional method with CAL support was shown to be the best option in comparison with the traditional method.

Basic and superior reasoning skills are woven into the clinical reasoning process just as they are used to solve any problem. As clinical reasoning is the central competence of medical education, development of these reasoning skills should occur throughout the undergraduate medical curriculum. The authors describe here a method of teaching reasoning skills in a clinical context during a human anatomy course.

The aim of this study was to establish safety ranges for the third vertebral artery segment (V3) for craneocervical procedures. Injury to V3 represents a potentially catastrophic complication. Its tortuous path and complex relationship with neighboring structures, increasing the risk. Ten male adult cadavers (20 vertebral arteries) with arterial infiltration of red latex were studied. The length, angles and anatomical measurements were obtained between the selected surgical landmarks and the portions of V3 segment. The horizontal portion has a length of 32.7 ± 3.6 mm with an angulation of 115.1 ± 8.3 degrees. The mean distances of the horizontal portion were: from the midline to the V3 groove of C1 posterior arch (24.7 ± 6.3 mm); from C1 pars interarticularis to the V3 distal loop of V3 (8.9 ± 1.4 mm). The vertical portion has a length 32.5 ± 5.6 mm with an angulation of the proximal loop of 113.6 ± 5.8 degrees. The mean distances between the C2 spinous process to the medial surface of the distal loop (43.8 ± 4.2 mm); from the C1-C2 joint to the V3 vertical portion (9.5 ± 1.5 mm); from C2 pars interarticularis to V3 in the C2 transverse foramen (6.5 ± 3.4 mm); from C2 pars interarticularis to V3 in the C1 transverse foramen (17.5 ± 4.5 mm). We reported four potential sites where V3 can be injured during four different surgical procedures: exposure of the posterior arch of C1, and pars interarticularis of C1 in the horizontal portion and exposure of the C1-C2 joint, and placement of C1-C2 transarticular screws one in the vertical portion. We provide measurements of redundancy and safety ranges to reduce the risk of injury to the V3 segment during craniocervical surgical procedures.

Determining the optimal conditions for learning anatomy will help medical students to do better in a gross anatomy course. We examined the two types of anatomy courses offered in our institution: slow-paced (SP) and fast-paced (FP) courses, in which the same content is taught in approximately the same number of hours (SP ‫؍‬ 91 hr; FP ‫؍‬ 90 hr), but the duration of each course differed (SP ‫؍‬ 91 1-hr sessions lasting 20 weeks; FP ‫؍‬ 45 2-hr sessions lasting 9 weeks). The objective of this study was to find out whether a relationship exists between anatomy course pace and achievement. Two groups of students were tested on their anatomy knowledge both before beginning and after completing either the SP or the FP course. The average difference in scores obtained on the pre-and postcourse tests for each group was obtained and a t-test was used (P < 0.05) to compare the mean score for each group. A significant difference was found between group SP and group FP, with the highest achievement obtained by group SP. The pace of the course is thus a factor that influences achievement. Anat Rec (Part B: New Anat) 289B:134 -138, 2006.