Choice of valve type and poor ventricular catheter placement: Modifiable factors associated with ventriculoperitoneal shunt failure
Highlights
- •The main aim of this study was to identify and describe any factors associated with long term shunt survival and in particular, to seek any modifiable factors.
- •Following ethics approval, we retrospectively reviewed the medical records of eligible patients who underwent VP shunt placements at Monash Medical Centre between 2005–2009, these patients were subsequently followed up by collecting clinical, demographic and operative data up to December 2013.
- •Overall, 140 patients were included in this study and 58 of them underwent at least one revision procedure during the study period.
- •Poor shunt catheter placement, which was described in this study as catheter tip outside of the ventricular system, was found to be the strongest predictor of shunt survival, therefore leading to the conclusion that aiming to place the catheter tip within the ventricular system may be the best way to ensure long-term shunt survival.
Abstract
Ventriculoperitoneal (VP) shunt insertion is a common neurosurgical procedure, essentially unchanged in recent years, with high revision rates. We aimed to identify potentially modifiable associations with shunt failure. One hundred and forty patients who underwent insertion of a VP shunt from 2005–2009 were followed for 5–9?years. Age at shunt insertion ranged from 0 to 91?years (median 44, 26% <18?years). The main causes of hydrocephalus were congenital (26%), tumour-related (25%), post-haemorrhagic (24%) or normal pressure hydrocephalus (19%). Fifty-eight (42%) patients required ?1 shunt revision. Of these, 50 (88%) were for proximal catheter blockage. The median time to first revision was 108?days. Early post-operative CT scans were available in 105 patients. Using a formal grading system, catheter placement was considered excellent in 49 (47%) but poor (extraventricular) in 13 (12%). On univariate analysis, younger age, poor ventricular catheter placement and use of a non-programmable valve were associated with shunt failure. On logistic regression modelling, the independent associations with VP shunt failure were poor catheter placement (odds ratio [OR] 4.9, 95% confidence interval [CI] 1.3–18.9, p?=?0.02) and use of a non-programmable valve (OR 0.4, 95% CI 0.2–1.0, p?=?0.04). In conclusion, poor catheter placement (revision rate 77%) was found to be the strongest predictor of shunt failure, with no difference in revisions between excellent (43%) and moderate (43%) catheter placement. Avoiding poor placement in those with mild or moderate ventriculomegaly may best reduce VP shunt failures. There may also be an influence of valve choice on VP shunt survival.
