Purpose or Case Report: Ventriculoperitoneal (VP) shunt series X-rays are the gold standard for post-operative assessment of shunt hardware. Radiographic abnormalities, including catheter discontinuities, coiling, and kinks, are flagged by radiologists as potential indicators of shunt malfunction, but the clinical consequences are unclear. The present study aims to determine if abdominal tight, interwoven coils (“bird’s nest” coiling) and distal kinked catheter findings on imaging are predictors of near-term shunt failure.
Methods & Materials: We analyzed 4997 shunt series X-rays performed at our institution from January 2010 to September 2023. We included all exams performed in the immediate post-operative period (up to 48 hours after surgery) with tight coils or kinked catheters noted in the radiology report.
Results: Six patients (66.7% male) exhibited bird’s nest coiling on post-operative X-rays. Of these, two (33.3%) were from initial shunt placements, and four (66.7%) were revisions. All patients with bird’s nests experienced shunt failure within 60 days (median: 10 days, IQR: 21), with revision surgery consisting of externalization (33.3%), valve and distal catheter replacement (16.7%) and distal catheter revision (50%). Six patients had X-rays revealing kinked catheters; five (83.3%) were initial placements, and one (16.7%) was a revision. Three patients (50%) with kinked catheters required revision, with median interval of 300 days (IQR: 402 days) to revision surgery. Patients with bird’s nest coiling had higher likelihood of revision within 60 days compared to those with kinked catheters (p=0.002).
Conclusions: Bird’s nest coiling in the distal catheter system may predict early shunt failure and warrants special radiologic attention due to the need for prompt surgical exploration. Conversely, kinked catheters are less predictive of immediate failure and do not necessarily require urgent intervention. Radiology reports of SSXR help triage patients presenting with a clinical picture that may suggest shunt failure. Identifying studies that demonstrate bird’s nest coiling and flagging those for urgent surgical attention will help expedite patients to the operating room (OR) for urgent revision. Findings of abdominal kinked catheters don’t necessarily predict shunt failure; therefore, these findings may not warrant the same urgency in patient management.