Introduction: Endoscopic Third Ventriculostomy(ETV) has become the primary treatment for aqueductal stenosis hydrocephalus. While research suggests surgical advantages, the potential for continued ventriculomegaly raises concerns regarding cognitive outcome. Specifically, ongoing ventriculomegaly may result in greater frontal executive dysfunction post intervention. In the current study we examined the relationship between ventricular size and executive performance in patients post ETV. We hypothesized that the larger ventricular size seen in ETV will result in reduced performance on executive tasks.
Methods: MRI based ventricular to cortex ratios (VCR) were calculated for all patients. Patients also completed a series of standard neuropsychological tests assessing executive skills: Wechsler Test of Adult Reading (WTAR); Sorting from the Delis Kaplan Executive Function System (DKEFS), Figural Copy (FC) from the Repeatable Battery for Neuropsychological Status (RBANS), Trail Making Test (TMT), Stroop Color Work Test (SCWT), Controlled Oral Word Association Test (COWAT) and Clock Drawing test. Correlations were conducted between tests and VC ratios.
Results: The sample included 10 medically stable patients one year post ETV surgery with a mean age of 37.7 years (sd=14.16) with a mean of 13 years of education (sd=3.5) and of average intelligence [WTAR 97.50 (sd=14.8)]. V/C ratio mean was .403 (sd=.137). Significant correlations were found between the V/C ratio and all executive functioning tasks. [SCWT r=-.642, p=.023; TMT-A r=-.926, p=.000; TMT-B r=-.650, p=.021; DKEFS Free Sort r=-.697, p=.013; DKEFS Description Sort r=-.582, p=.039; DKEFS Sort Recognition r=-.627, p=.026, Clock Free r=-.911, p=.000, RBANS figure copy r=-.762, p=.005].
Conclusions: ETV patients’ ongoing ventriculomegaly appears to hinder executive functioning. Specifically ventricular size negatively correlated with performance on measures of processing speed, sustained attention, mental flexibility, problem solving, and planning skills. The pressure on surrounding frontal networks and white matter tracks may explain this relationship. Limitations include small sample size.
Patient Care: This data may be clinically useful when discussing intervention options.
Learning Objectives: 1. To gain a better understanding of the relationship between ventricular size and executive functioning.
2. To gain a better understanding of the potential long term neurocognitive impact of ETV intervention.