Abstract:Objective To investigate the clinical effects and influencing factors of ventriculo-peritoneal (V-P) shunt with different shunt tubes in patients with idiopathic normal pressure hydrocephalus(iNPH). Methods The clinical data of 69 patients with iNPH treated from January 2014 to January 2017 were analyzed retrospectively.All patients were diagnosed as "possible" and "probable" iNPH according to the International and Japanese Guidelines for the Diagnosis and Treatment of iNPH,and were positive in cerebrospinal fluid tap test before operation and received V-P shunt.According to the type of shunt tube,50 cases of shunt tube with adjustable pressure anti-siphon device(ASD) (adjustable pressure ASD group),and 19 cases of shunt tube with non-adjustable pressure anti-siphon device (ASD group) were used. The Modified Rankin scale was used to evaluate the clinical effects between two groups,and the influencing factors of prognosis were analyzed. Results Of the 69 patients with iNPH,8 were lost to follow-up,and the total effective rate of the remaining 61 patients was 83.6% (51/61).The significant effective rate,effective rate and ineffective rate were 62.2%,24.5% and 13.3%,respectively in adjustable pressure ASD group and 18.7%,56.3% and 25.0%,respectively in ASD group.There were statistical differences between two groups(P=0.006).The research showed that gender,age,stage of disease,and cerebrospinal fluid pressure measured by lumbar puncture had no obvious influences on postoperative outcome(all P>0.05),and adjustable ASD was a favaurite factor affecting the efficacy of V-P shunt(P<0.01). Conclusions V-P shunt is safe and effective in the treatment of iNPH,and the adjustable pressure ASD is better in clinical practice and can be used as the first choice.It is easy to adjust for the patients with excessive or insufficient shunt after operation.In view of the limited data,it has not been found that gender,age,course of disease and preoperative pressure have significant impacts on the postoperative outcome.