Prognostic value of magnetic resonance imaging-visible perivascular spaces in patients with idiopathic normal pressure hydrocephalus.

BACKGROUND

Only a few studies have focused on the effects of perivascular spaces (PVS) on the postoperative prognosis of patients with idiopathic normal pressure hydrocephalus (iNPH). Therefore, this study aimed to determine the ability of magnetic resonance imaging (MRI)-visible PVS to predict prognosis after surgery for iNPH.

METHODS

Eighty-seven patients with iNPH operated with shunt surgery and clinically assessed before and 12 months after surgery were included in this study. The semi-quantitative visual rating methods and quantitative volume of MRI-visible PVS were used to evaluate the preoperative MRI. The primary and secondary endpoints at 1 year after surgery were improvements in the modified Rankin scale and iNPH grading scale, respectively. Predictors of improvement were analyzed using multivariate logistic regression model and receiver operating characteristic (ROC) analysis.

RESULTS

Of the 87 patients with iNPH (69±7 years), 51 were men. The improvement rates in the primary and secondary outcomes were 61% and 68%, respectively. There was no difference between shunt improvement and non-improvement in the preoperatively visual rating methods and quantitative volume of MRI-visible PVS (all P>0.05). None of the preoperatively visual rating methods and quantitative volume of MRI-visible PVS were independently associated with improvement one year after surgery on the basis of primary or secondary outcomes after adjusting for sex, age, duration, smoking, alcohol consumption, diabetes, and hypertension (all P>0.05).

CONCLUSIONS

The ability of visual rating methods and quantitative volume of MRI-visible PVS to predict prognosis after shunt surgery for iNPH is limited. Preoperative PVS burden should not be used to exclude patients with iNPH from surgery.