Optic chiasmal edema observed on T2-weighted MR images: a reversible finding in obstructive hydrocephalus

Jpn J Radiol. 2015 Mar;33(3):140-5. doi: 10.1007/s11604-015-0393-6. Epub 2015 Jan 29.

Abstract

Purpose: To evaluate the clinical significance of optic chiasmal edema (OCE) observed in hydrocephalus.

Materials and methods: Twenty patients with obstructive hydrocephalus and eight patients with communicating hydrocephalus were recruited. We classified both groups into OCE-positive and negative subgroups on three-dimensional T2-weighted images. In the obstructive hydrocephalus group, the pre- and postoperative periventricular hyperintensity (PVH) grade, Evans index, and third ventricle diameter were compared between the subgroups. The visual disturbances were reviewed in the medical records.

Results: Eleven obstructive hydrocephalus patients (55 %) had OCE, while none of communicating hydrocephalus patients did. OCE was improved in all patients postoperatively. Preoperative PVH grade was significantly higher in the OCE-positive subgroup (p < 0.01). There were no statistically significant differences in the other indices. Visual disturbances were observed in two OCE-negative patients alone.

Conclusion: OCE is a reversible finding frequently observed in obstructive hydrocephalus and may not be associated with visual disturbances.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Brain Edema / diagnosis*
  • Child
  • Child, Preschool
  • Female
  • Humans
  • Hydrocephalus / diagnosis*
  • Magnetic Resonance Imaging* / methods
  • Male
  • Middle Aged
  • Optic Chiasm*