Standardized spinal MRI protocol: diagnosing spontaneous intracranial hypotension and correlating with brain MRI

To evaluate a standardized cervical-thoracic-lumbar (CTL) contrast-enhanced (CE)-MRI protocol for spinal findings in spontaneous intracranial hypotension (SIH) and their correlation with brain MRI.

This retrospective study included SIH-suspected patients who underwent spine MRI from March 2019 to February 2023. Diagnosis was based on clinical criteria, using a 3T MRI with a standardized spine protocol. MRI diagnostic criteria included spinal (e.g., spinal longitudinal epidural fluid collection [SLEC], dural enhancement [DE]) and brain findings (four qualitative methods including venous sinus engorgement [VSE], pachymeningeal enhancement [PE], and brain sagging [BS] as confirmatory diagnostic criteria; and four quantitative methods). Patients were classified into Group 1 (brain MRI-positive showing VSE, PE or BS) and Group 2 (brain MRI-negative). Demographics and MRI findings were compared in both groups using t-tests or chi-square statistics.

Among 53 SIH patients, 42 with spine MRI-positive findings underwent brain MRI (mean age 43.95 ± 12.26 years, 66.7% female), with 27 in Group 1 and 15 in Group 2. Group 1 demonstrated significantly wider sagittal and axial extents of SLEC (full range: 85.2%, circumferential: 82.1%; p < 0.001, p = 0.011), and a higher prevalence of the C1-2 sign, while Group 2 exhibited these features less frequently (85.2% vs. 53.3%, p = 0.024). Brain MRI findings in Group 1 included VSE (92.6%), PE (66.7%), and BS (7.4%), with subdural fluid collection also higher (37.0%, p = 0.007). Other brain parameters showed no significant differences.

The standardized CTL CE-MRI protocol enables comprehensive SIH diagnosis, when brain MRI findings are negative or equivocal.