Prevalence of Traumatic Findings on Routine MRI in a Large Cohort of Professional Fighters

Abstract

Background and purpose: Previous studies investigating MR imaging abnormalities among fighters have had small sample sizes. This investigation assessed a large number of fighters using the same conventional sequences on the same scanner.

Materials and methods: Conventional 3T MR imaging was used to assess 499 fighters (boxers, mixed martial artists, and martial artists) and 62 controls for nonspecific WM changes, cerebral microhemorrhage, cavum septum pellucidum, and cavum vergae. The lengths of the cavum septum pellucidum and cavum vergae and the ratio of cavum septum pellucidum to the septum pellucidum lengths were assessed.

Results: The prevalence of nonspecific WM changes was similar between groups. Fighters had a prevalence of cerebral microhemorrhage (4.2% versus 0% for controls, P = .152). Fighters had a higher prevalence of cavum septum pellucidum versus controls (53.1% versus 17.7%, P < .001) and cavum vergae versus controls (14.4% versus 0%, P < .001). The lengths of the cavum septum pellucidum plus the cavum vergae (P < .001), cavum septum pellucidum (P = .025), and cavum septum pellucidum to the septum pellucidum length ratio (P = .009) were higher in fighters than in controls. The number of fights slightly correlated with cavum septum pellucidum plus cavum vergae length (R = 0.306, P < .001) and cavum septum pellucidum length (R = 0.278, P < .001). When fighters were subdivided into boxers, mixed martial artists, and martial artists, results were similar to those in the whole-group analysis.

Conclusions: This study assessed MR imaging findings in a large cohort demonstrating a significantly increased prevalence of cavum septum pellucidum among fighters. Although cerebral microhemorrhages were higher in fighters than in controls, this finding was not statistically significant, possibly partially due to underpowering of the study.

Fig 1.

Example of CSP and septum pellucidum measurements.

Fig 2.

Prevalence of MR imaging findings in fighters versus controls.

Fig 3.

Example of cerebral microhemorrhage in a fighter.

Fig 4.

Schematic diagram showing the location of all cerebral microhemorrhages observed from all 21 fighters in the study. Although 50 CMHs were observed, 2 fighters had a disproportionate share, and their CMHs have their own symbol of a cross and a triangle. The simplified diagram does not show all the sulci. Most CMHs were actually located near the cortex, and a few were located in the deep white matter.

Fig 5.

Schematic diagram showing the location of all 15 nonspecific white matter changes observed from 5 randomly selected controls with foci shown by crosses. For comparison of the distribution, 5 randomly selected fighters with NSWMC are shown by circles, which totaled 12. As in Fig 4, the simplified diagram does not show all the sulci, most NSWMCs were actually located near the cortex, and only 2 were located in the periventricular margins.

Fig 6.

The number of fights in fighters with and without cavum septum pellucidum, cavum vergae, cerebral microhemorrhages, and nonspecific white matter change.

Fig 7.

Septum pellucidum length, cavum septum pellucidum length, cavum septum pellucidum plus cavum vergae length, and maximum transverse diameter of the CSP in fighters versus controls.

Fig 8.

Cavum septum pellucidum and cavum septum pellucidum plus cavum vergae to septum pellucidum ratios in fighters versus controls.