Magnetic resonance imaging findings in Parinaud's syndrome: comparing pineal mass findings to other etiologies.

PURPOSE: In a recent study, it was found that, although intrinsic midbrain signal abnormality (IMSA) on MRI is associated with Parinaud's syndrome (PS) in patients with pineal gland masses (PM), it had no predictive value with respect to resolution of PS. We sought to compare the PM and non-pineal etiologies (NPE) of PS by reviewing imaging features of PS and whether or not they are predictive of resolution of symptoms.

METHODS: We reviewed electronic medical records from 1980 to 2017 and identified 71 patients with PS from any etiology who had MR imaging: 26 with PM and 45 with NPE. We subdivided the 45 NPE patients into those with intrinsic midbrain lesions (IMBL) (n = 23) and those with extrinsic midbrain lesions (EMBL) (n = 22). PS resolution and hydrocephalus data were collected. Imaging studies were reviewed for the presence of IMSA and hydrocephalus.

RESULTS: PS patients with EMBL were less likely to have IMSA than those with PM or IMBL (p ≤0.001). PS resolution occurred more commonly with PM than IMBL and NPE (p = 0.03, p = 0.01). For all NPE patients, resolution of PS occurred with equal frequency in patients with and without IMSA (p = 1.00). Hydrocephalus occurred more frequently in patients with PM and EMBL than IMBL (p = 0.01, p = 0.03).

CONCLUSIONS: IMSA is present more often in patients with PS from PM or IMBL than in patients with EMBL. EMBL, including PM, have an increased likelihood for PS resolution. There is no predictive value of IMSA with respect to resolution of PS in NPE as well as PM.