[Adult chronic idiopathic hydrocephalus-diagnosis, treatment and evolution. Prospective study]

At present, chronic hydrocephalus or normal pressure hydrocephalus (NPH) has a controversial diagnosis in which multiple diagnostic and therapeutic techniques have been used with variable degrees of postoperative success. The aim of our study is to evaluate a number of patients diagnosed with adult chronic idiopathic hydrocephalus who were treated with a CSF shunt at our centre between 2006 and 2009 through clinical scales and radiological controls pre- and postoperatively.

We prospectively analysed 40 patients. The diagnosis of idiopathic NPH was established when patients met 3 criteria: (i)clinical; (ii)radiological (Evans >0.3), and (iii)hydrodynamic (Katzman infusion test with Rout >12) or pathological ICP monitoring (B waves in over 20% of a nocturnal registration). We used a low-pressure DVP 5/35 GAV in all cases. Clinical assessments were conducted at 3, 6 and 12 months and radiological assessments at 6 months postoperatively. The clinical improvement of patients was assessed with the NPH, modified RANKIN and modified PFEIFFER rating scales.

The study of risk factors (age, gender, smoking, drinking, arterial hypertension, diabetes mellitus, dyslipidemia) did not establish statistically significant relationships. A statistically significant improvement was observed (P<.01) in the NPH and RANKIN tests at 3, 6 and 12 months. Clinical improvement values obtained were: NPH 73%, 74% and 64%, and RANKIN 54%, 72% and 56%, respectively. The PFEIFFER scale only showed a significant improvement at 12 months. These improvements were classified into various levels (high, moderate, mild and no improvement). The initial mean Evans index was 0.385, and 0.3675 postoperatively. There was only one infection of the valvular system (2%) without further complications. Morbidity and mortality related to the procedure were 0%.

An appropriate selection of patients through clinical, radiological, hydrodynamic and ICP monitoring criteria enables us to obtain good results and a low complication rate.