Cognitive improvement after endoscopic third ventriculostomy surgery in long-standing overt ventriculomegaly in adults

OBJECTIVE Long-standing overt ventriculomegaly in adults (LOVA) is a chronic form of hydrocephalus that can lead to cognitive deficits. Data on the cognitive profile of patients with LOVA and cognitive outcomes of endoscopic third ventriculostomy (ETV) are, however, scarce and mostly qualitative. METHODS Twenty-three consecutive patients with LOVA hydrocephalus underwent ETV surgery, and their cognitive status was assessed before surgery, immediately after surgery, and at the 5-month follow-up. Cognitive function was assessed using a neuropsychological battery measuring 6 cognitive domains: general cognitive status, attention/executive function, language, visuospatial skills, short-term memory, and long-term memory. Cognitive reserve was also estimated through a measure of premorbid IQ to assess its potential influence together with other clinical and demographic variables. RESULTS Patients with LOVA did not experience general cognitive decline but rather selective long-term memory (p < 0.001) and visuospatial skills (p = 0.001) deficits alone. Moreover, ETV surgery led to significant immediate postoperative improvement in both domains (p = 0.002 and p < 0.001 respectively), that persisted at follow-up (p < 0.001 for both). However, improvement was observed only in patients with higher premorbid IQ (p < 0.001), while the others did not improve (p > 0.532). CONCLUSIONS These findings confirm the effectiveness of ETV surgery and highlight the role of cognitive reserve in promoting plasticity of brain and cognitive functions thus fostering and predicting cognitive recovery.