The risk factors of symptomatic communicating hydrocephalus after stereotactic radiosurgery for unilateral vestibular schwannoma: the implication of brain atrophy

Int J Radiat Oncol Biol Phys. 2012 Nov 15;84(4):937-42. doi: 10.1016/j.ijrobp.2012.01.048. Epub 2012 Apr 9.

Abstract

Purpose: To identify the effect of brain atrophy on the development of symptomatic communicating hydrocephalus (SCHCP) after stereotactic radiosurgery (SRS) for sporadic unilateral vestibular schwannomas (VS).

Methods and materials: A total of 444 patients with VS were treated with SRS as a primary treatment. One hundred eighty-one patients (40.8%) were male, and the mean age of the patients was 53±13 years (range, 11-81 years). The mean follow-up duration was 56.8±35.8 months (range, 12-160 months). The mean tumor volume was 2.78±3.33 cm3 (range, 0.03-23.30 cm3). The cross-sectional area of the lateral ventricles (CALV), defined as the combined area of the lateral ventricles at the level of the mammillary body, was measured on coronal T1-weighted magnetic resonance images as an indicator of brain atrophy.

Results: At distant follow-up, a total of 25 (5.6%) patients had SCHCP. The median time to symptom development was 7 months (range, 1-48 months). The mean CALV was 334.0±194.0 mm2 (range, 44.70-1170 mm2). The intraclass correlation coefficient was 0.988 (95% confidence interval [CI], 0.976-0.994; p<0.001). In multivariate analysis, the CALV had a significant relationship with the development of SCHCP (p<0.001; odds ration [OR]=1.005; 95% CI, 1.002-1.007). Tumor volume and female sex also had a significant association (p<0.001; OR=1.246; 95% CI, 1.103-1.409; p<0.009; OR=7.256; 95% CI, 1.656-31.797, respectively). However, age failed to show any relationship with the development of SCHCP (p=0.364).

Conclusion: Brain atrophy may be related to de novo SCHCP after SRS, especially in female patients with a large VS. Follow-up surveillance should be individualized, considering the risk factors involved for each patient, for prompt diagnosis of SCHCP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Atrophy / complications
  • Brain / pathology*
  • Child
  • Confidence Intervals
  • Female
  • Follow-Up Studies
  • Humans
  • Hydrocephalus / etiology*
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Neuroma, Acoustic / pathology
  • Neuroma, Acoustic / surgery*
  • Radiosurgery / adverse effects
  • Radiosurgery / methods*
  • Risk Factors
  • Sex Factors
  • Time Factors
  • Tumor Burden
  • Young Adult