American football players and other individuals exposed to repetitive head impacts can exhibit a constellation of later-life cognitive and neuropsychiatric symptoms. While tau-based diseases such as chronic traumatic encephalopathy can underpin certain symptoms, contributions from non-tau pathologies from repetitive head impacts are increasingly recognized. We examined cross-sectional associations between myelin integrity using immunoassays for myelin-associated glycoprotein and proteolipid protein 1 with risk factors and clinical outcomes in brain donors exposed to repetitive head impacts from American football. Immunoassays for myelin-associated glycoprotein and proteolipid protein 1 were conducted on dorsolateral frontal white matter tissue samples of 205 male brain donors. Proxies of exposure to repetitive head impacts included years of exposure and age of first exposure to American football play. Informants completed the Functional Activities Questionnaire, Behavior Rating Inventory of Executive Function-Adult Version (Behavioral Regulation Index), and Barratt Impulsiveness Scale-11. Associations between myelin-associated glycoprotein and proteolipid protein 1 with exposure proxies and clinical scales were tested. Of the 205 male brain donors who played amateur and professional football, the mean age was 67.17 (SD = 16.78), and 75.9% (n = 126) were reported by informants to be functionally impaired prior to death. Myelin-associated glycoprotein and proteolipid protein 1 correlated with the ischaemic injury scale score, a global indicator of cerebrovascular disease (r = −0.23 and −0.20, respectively, Ps < 0.01). Chronic traumatic encephalopathy was the most common neurodegenerative disease (n = 151, 73.7%). Myelin-associated glycoprotein and proteolipid protein 1 were not associated with chronic traumatic encephalopathy status, but lower proteolipid protein 1 was associated with more severe chronic traumatic encephalopathy (P = 0.03). Myelin-associated glycoprotein and proteolipid protein 1 were not associated with other neurodegenerative disease pathologies. More years of football play was associated with lower proteolipid protein 1 [beta = −2.45, 95% confidence interval (CI) [−4.52, −0.38]] and compared with those who played <11 years of football (n = 78), those who played 11 or more years (n = 128) had lower myelin-associated glycoprotein (mean difference = 46.00, 95% CI [5.32, 86.69]) and proteolipid protein 1 (mean difference = 24.72, 95% CI [2.40, 47.05]). Younger age of first exposure corresponded to lower proteolipid protein 1 (beta = 4.35, 95% CI [0.25, 8.45]). Among brain donors who were aged 50 or older (n = 144), lower proteolipid protein 1 (beta = −0.02, 95% CI [−0.047, −0.001]) and myelin-associated glycoprotein (beta = −0.01, 95% CI [−0.03, −0.002]) were associated with higher Functional Activities Questionnaire scores. Lower myelin-associated glycoprotein correlated with higher Barratt Impulsiveness Scale-11 scores (beta = −0.02, 95% CI [−0.04, −0.0003]). Results suggest that decreased myelin may represent a late effect of repetitive head impacts that contributes to the manifestation of cognitive symptoms and impulsivity. Clinical–pathological correlation studies with prospective objective clinical assessments are needed to confirm our findings.

The objective of this Vesalius Master’s capstone project was to develop a lesson for teaching the Infratemporal fossa (ITF) using an Anatomage table, to first year students in the Medical Gross Anatomy course. The ITF is an important space within the head and neck, through which many structures pass or are housed but is difficult to visualize both in the cadaver and in 2D images. In contrast, the Anatomage table provides opportunities for rotatable three‐dimensional views. The lesson was designed to enable students to simultaneously visualize structures within the fossa and the relationships of these structures to deeper and more superficial structures in the area. A virtual dissection of the ITF from superficial to deep was created as 4 separate preset screens on the Anatomage table. Preset one showed the structures of the head and neck superficial to the ITF. The second preset showed a deeper view into the ITF in which the zygomatic arch and mandible were removed to see the muscles within in the ITF. Preset three was a view of the cranial nerves (CN), specifically CN V3 and its branches within the ITF. Preset four was a view that showed the vasculature within the ITF, specifically the maxillary artery and its branches. The lesson was designed to use the Anatomage table features to highlight the 3D relationships of these structures, supplemented with a worksheet that followed the virtual dissection and provided students with the high yield information for the course practical and written examinations. The lesson was run 5 times for a total of 35 students. After the session, students completed an evaluation of the effectiveness of this lesson, the lesson resources, and the instructor. Overall, the students felt that this method of teaching the ITF was highly effective for teaching the structures and function of the ITF contents. The students expressed that using the Anatomage table allowed them to orient themselves to the regions in contrast to what other resources allow. The supplemental worksheet was an important complementary resource to the lesson as it functioned as a study guide for the exam. This study demonstrates that the Anatomage table is a useful tool for teaching a region of the body that is difficult to demonstrate in the cadaver. This lesson allowed students to incorporate other relationships within the head and neck and provided context to these relationships. The method of teaching allowed the students to work together and actively engage in the lesson, which was effective for understanding the content. This teaching method can be used both to supplement cadaver teaching and in a context in which cadavers are not accessible.

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