[Otologic symptoms and audiological characteristics in patients with spontaneous intracranial hypotension]

Objective: To explore otologic symptoms and audiological features in patients with spontaneous intracranial hypotension (SIH), and provide reference for clinical diagnosis and treatment. Methods: The clinical data of 348 patients with SIH who were hospitalized and treated at the Chinese PLA General Hospital from January 2001 to June 2025 were retrospectively reviewed. Demographic characteristics, otologic symptoms (hearing loss, tinnitus, ear fullness, dizziness/vertigo), audiological findings, and their associations were analyzed. Results: Among the 348 patients, there were 156 males (44.8%) and 192 females (55.2%). The mean age was (39.5±14.4) years, with the highest proportion in the 30-39-year group (28.7%, 100/348), followed by the 40-49-year group (20.7%, 72/348). All patients presented with headache. Ear symptoms were detected in 104 cases (29.9%). Among them, hearing loss was found in 43 cases (12.4%), with 25 bilateral cases (58.1%) and 18 unilateral cases (41.9%); 51 cases (14.7%) and six cases (1.7%) had tinnitus and ear fullness, respectively; 55 cases (15.8%) had dizziness/vertigo. Of the 34 patients who completed the audiological test, 32 cases (94.1%) had sensorineural hearing loss and two cases (5.9%) had conductive hearing loss. Of 68 ears assessed, mild, moderate, moderately severe, and severe loss occurred in 22, 13, four, and two ears respectively; mild-to-moderate loss accounted for 51.5% (35/68). Descending audiograms were most frequent (36.8%, 25/68), followed by notch (23.5%, 16/68), flat (22.1%, 15/68), and ascending types (17.6%, 12/68). Hearing loss occurred more frequently in the older age group (>18 years old) and in patients with tinnitus or dizziness/vertigo compared with other groups (all P<0.001). Conclusions: Otologic symptoms are common in patients with SIH, with hearing loss, tinnitus, and dizziness/vertigo being predominant. Hearing loss is mainly mild-to-moderate sensorineural type, and the descending audiogram is the most frequent pattern.