Effect of Osteoporotic Condition on Ventriculomegaly and Shunt-Dependent Hydrocephalus After Subarachnoid Hemorrhage

Background and Purpose: Hydrocephalus is a common complication in aneurysmal rupture subarachnoid hemorrhage (SAH). As both the bone and arachnoid trabeculae are composed of type 1 collagen, we identified the possible relationship between bone mineral density and ventriculomegaly and shunt-dependent hydrocephalus (SDHC) development after aneurysmal rupture SAH in younger patients. Methods: We measured frontal skull Hounsfield unit (HU) values on brain computed tomography upon admission, and mean frontal skull HU values were used instead of T-score value. Hazard ratios were calculated using Cox regression analysis to identify whether osteoporotic condition is an independent predictor for ventriculomegaly and SDHC after surgical clipping for SAH in younger patients. Results: Altogether, 412 patients (≤65 years) who underwent surgical clipping for primary spontaneous SAH from a ruptured aneurysm were enrolled in this 11-year analysis in 2 hospitals. We observed that the first tertile group of skull HU was an independent predictor of SDHC after SAH compared with the third tertile of skull HU values (hazard ratio, 2.55 [95% CI, 1.25–5.20]; P =0.010). There were no significant interactions between age and skull HU with respect to ventriculomegaly and SDHC in younger patients. Conclusions: Our study suggests a relationship between possible osteoporotic conditions and ventriculomegaly and SDHC development after SAH in younger patients. Our findings may be useful in predicting hydrocephalus in young SAH patients using a convenient method of measuring skull HU value on brain computed tomography upon admission.