Long term prognosis of ventriculoatrial shunt for idiopathic normal pressure hydrocephalus in the elderly

Abstract

Objective: A retrospective study was conducted to access the long-term prognosis of inserting the Ventriculoatrial (VA) shunt in the elderly for the idiopathic normal pressure hydrocephalus (iNPH). Material and Methods: Retrospective data is collected from April 2004 to August 2015, and 1065 patients were selected. Patients who underwent surgical examination or surgery in suspected iNPH were included. Tap test is done in all cases and found to be effective for 968 cases and 656 VA shunts for 614 cases. Out of 614 cases there are 440 cases in which patient age were over 75 years. Of these 440 cases only 141 cases were able to observe 03 years or more after the surgery, 37 deaths and 05 cases with survival and unknown prognosis were found among them. So we analyzed this group mainly in 99 cases that the prognosis after 03 years was known. We access the outcome of VA shunt by the modified Rankin scale (mRS), iNPH grading scale (iNPHGS) and complications in the operative 656 cases and in 03 years follow up of 141 patients. Results: Of 141, there are 78 males and 63 females. Age at the time of VA shunt insertion was 81.5±4.1 years and age at final follow-up was 85.2±4.4 years. The proportion of patients who achieved a favorable outcome by complications was 97.9% in 03 years follow-up period and 87.7% in which follow-up is less than 03 years. At the time of VA shunt insertion out of 141, 57 patients lies between 75-79 years, 57 between 80-84, 24 between 85 to 89, and only 03 were found to be 90 years or more. At the time of final follow-up at 03 years, 15 patients lies between 75 to 79 years, 56 between 80 to 84 years, 57 between 85 to 89 years and 23 patents were found to be 90 years or greater. 70 cases or almost 50% exceeded 85 years. At the time of VA shunt 1, 11, 39, 51, 36, 3, 0 patients were in 0 to 6 modified Rankin Scale Score respectively and at 03 years follow-up 8, 19, 32, 29, 9, 2, 37 were in 0 to 6 mRS respectively. Comparison of the study is done with SIPHONI study on VP shunt and LP shunt. Conclusion: Patients suspected of having idiopathic normal pressure hydrocephalus were treated by VA shunt and found no significant difference in serious adverse effects. This study shows that VA shunt is an effective choice for iNPH in the late elderly population, but it needs more randomized control trial to establish its efficacy.