Etiological, clinical, and radiological features of longitudinally extensive myelopathy in Chinese patients

•Longitudinally extensive myelopathy is often associated with neuromyelitis optica spectrum disorders in Chinese patients.•Over half of the longitudinally extensive myelopathy cases are attributed to other important causes.•The etiological distribution in Chinese patients is different to western populations.•Clinical and imaging features may facilitate a differential diagnosis.

Longitudinally extensive myelopathy (LEM) is a rare spinal syndrome, and was mostly assessed in western populations. In order to investigate the etiological, clinical, and radiological features of LEM in Chinese patients, we retrospectively analyzed eighty-nine (40 men and 49 women, median age 45.9 ± 15.7 years) patients with LEM hospitalized in China-Japan Friendship Hospital. LEM comprised autoimmune inflammatory myelitis (n = 53), metabolic and compressive disorders (n = 13), vascular diseases (n = 10), neoplastic diseases (n = 7), infectious diseases (n = 4), and syringomyelia (n = 2). Neuromyelitis optica spectrum disorders (NMOSD) was the most common cause of transverse myelopathy identified in LEM (38/89 [42.7%]) characterized by intractable vomiting and hiccups and painful tonic spasms. Subacute combined degeneration and anterior spinal artery syndrome accounted for the largest non-transverse LEM, which selectively affected the spinal dorsal and/or lateral columns and the spinal anterior region, respectively. Radicular pain was common in anterior spinal artery syndrome. Postrema (n = 15, 39.5%) and cervical (n = 31, 81.6%) lesions were significantly increased in NMOSD versus non-NMOSD (n = 7, 13.7% and n = 34, 66.7%, respectively, p < 0.05]. Axial T2-weighted MRI indicated that 46 (51.7%) patients exhibited complete lesions; 43 (48.3%) patients exhibited non-transverse lesions, mainly unilateral or symmetrical tract lesions. Twenty-four (51.1%) LEM patients exhibited distinct gadolinium contrast enhancement. In this Chinese cohort, LEM was primarily attributed to NMOSD. While the etiological distribution in the non-NMOSD group was different from western populations, clinical and imaging features may facilitate a differential diagnosis.