Evaluation of the temporomandibular joint in epilepsy patients using high-resolution volumetric t2-weighted imaging

In this study, we aimed to anatomically evaluate temporomandibular joint (TMJ) degeneration in epilepsy patients using high-resolution volumetric T2-weighted imaging, which is routinely included in conventional multiparametric brain MRI protocols, without the need for additional morphological studies or supplementary imaging. Furthermore, we aimed to investigate the relationship between TMJ degeneration and disease duration, etiology, and seizure types. Between 2021 and 2024, brain MRI scans of 125 epilepsy patients and 133 healthy individuals were retrospectively evaluated at Düzce University Faculty of Medicine. The images were assessed over a 7-month period by two radiologists, one experienced and one inexperienced in central nervous system radiology. TMJ findings were classified into five categories: Category 0: normal, Category 1: effusion/synovial cyst, Category 2: disc degeneration, Category 3: disc displacement, Category 4: osseous findings. Some cases were included in more than one category. The assumption of normal distribution for numerical data was tested using the Kolmogorov-Smirnov test, and homogeneity of variances was assessed using Levene's test. Group comparisons were conducted using the Independent Samples t-test or Welch's test. Categorical variables were analyzed using Pearson's chi-square, Fisher's exact, or Fisher-Freeman-Halton tests. In the epilepsy group, the rate of having a normal TMJ structure was found to be 37.6%, whereas it was 54.9% in the control group; the difference was statistically significant. Bilateral TMJ pathologies were observed more frequently than unilateral ones, with a bilateral pathology rate of 40% in the epilepsy group compared to 24.8% in the control group. Bilateral and multiple TMJ pathologies were significantly more common in epilepsy patients than in the control group. While left-sided single and multiple TMJ pathologies showed significant differences across age groups, no such significance was observed on the right side. In both epilepsy and control groups, bilateral or single/multiple TMJ pathologies were statistically more frequent in female participants compared to males. When joint pathologies were evaluated individually, the rate of effusion on the right side was 63.5% in the epilepsy group and 84.0% in the control group, with the latter being significantly higher. However, disc degeneration was observed at a rate of 42.9% in the epilepsy group and 16.0% in the control group, which was statistically significant. Epilepsy patients with motor symptoms exhibited significantly more frequent unilateral or bilateral TMJ pathologies. In conclusion, our findings demonstrate with high specificity that TMJ pathologies are more prevalent in epilepsy patients and can be reliably detected using the 3D T2-SPACE sequence without the need for additional morphological studies or imaging. However, findings such as joint effusion and synovial cysts cannot be directly associated with epilepsy, as they are also commonly observed in asymptomatic individuals.