Approach to Slitlike Ventricles: Parietal-Occipital versus Frontal Burr Catheter Entry Sites

Slit ventricles can be a challenging target during shunt catheter insertion. Traditionally, the frontal approach has been considered optimal for small ventricles. At this center, routine use of electromagnetic (EM) stereotactic guidance (Stealth, Medtronic, Dublin, Ireland) has enabled a parietooccipital (P-O) burr hole approach to the frontal horns. We compare shunt placement and revisions required for patients with slit ventricles who had shunts inserted via a P-O approach versus frontal shunt.

We studied a retrospective cohort of patients with slit ventricles and a ventricular shunt inserted using EM guidance between 2012 and 2018. Slitlike ventricles were defined as the widest point of the lateral ventricle <3 mm. Outcome measures included placement accuracy and survival using the Kaplan-Meier curve. Optimal final catheter tip location was considered to be the frontal horn of the ipsilateral lateral ventricle.

Eighty-two patients (77 female, 5 male) aged 34.9 ± 10.8 years (mean ± standard deviation) had ventricular shunts inserted for idiopathic intracranial hypertension (n = 63), chiari/syrinx (n = 8), congenital (n = 10), and pseudomeningocele (n = 1). Of those identified, 35 had primary P-O shunts and 46 had frontal shunts. Overall, 94% of cases had the catheter tip sitting in the frontal horn. The P-O approach was just as accurate as the frontal approach. Eight P-O shunts and 9 frontal shunts required revision over a 60-month period. There was no significant different in shunt survival between the 2 approaches (P = 0.37).

EM-guided placement has enabled the P-O approach to be as safe and with equivalent survival to frontal approach. The accuracy of shunt placement between the 2 approaches was similar.