The Importance of Bright Spotty Lesions on Magnetic Resonance Imaging in Predicting Chronic Neuropathic Pain in Myelitis

<b>Background/Objectives</b>: Chronic neuropathic pain (CNP) stands as one of the most debilitating complications in patients with myelitis owing to its challenging management. Bright spotty lesions (BSLs) are frequently observed in neuromyelitis optica spectrum disorder (NMOSD), but few reports have discussed CNP in myelitis. We aim to demonstrate that BSLs could be one of the potential prognostic factors for CNP development in myelitis. <b>Methods</b>: We examined 63 patients diagnosed with myelitis. Patients were categorized into CNP and non-CNP groups. We assessed the severity of clinical symptoms and the oral steroid dose administered after pulse therapy. Spine magnetic resonance imaging (MRI) of each patient was reviewed to analyze the characteristics of myelitis. Serological and cerebrospinal fluid (CSF) findings were also examined to confirm the etiology. <b>Results</b>: CNP was observed in 27 patients (42.9%). The mean onset age of patients with CNP was 45.26 ± 14.16 years. The MRI lesions exhibited more enhanced features and bright spotty lesions (BSLs) in the CNP group (χ² test, <i>p</i> < 0.05). Patients with CNP received a lower oral steroid dose during the first month after symptom onset (χ² test, <i>p</i> < 0.05). Multivariate logistic regression analysis revealed that patients with CNP exhibited significant BSLs in their myelitis lesions on spine MRI (OR 4.965; 95% CI, 1.282 to 19.235, <i>p</i> = 0.02). <b>Conclusions</b>: Although the exact mechanism remains unknown, the presence of BSLs on spine MRI could serve as an independent prognostic factor for CNP development. Additionally, our study suggests that lower oral steroid doses administered immediately after symptom onset are associated with CNP development. Further investigation with a larger cohort is warranted to validate our findings.