Technical noteThe use of ultrasound for postoperative monitoring of cerebral bypass grafts: A technical report

•Post-operative bypass graft monitoring is a method to evaluate graft blood flow.•Post-operative EC-IC bypass graft monitoring is rapid, non-invasive and non-ionizing.•Post-operative EC-IC bypass graft monitoring has high inter-rater reliability.•Identifying potential graft pathologies ensures graft durability and patient safety.

Duplex ultrasound and transcranial Doppler are valuable tools for post-operative monitoring of extracranial-intracranial cerebral bypass grafts. Here we describe our technique for the evaluation of both high-flow and low-flow cerebral bypass grafts over a nine year period. 186 bypass grafts were studied daily during the inpatient period between Jan 2005 and Dec 2014 after surgery for various cerebrovascular pathologies. There was a technical success rate of 97%. Duplex ultrasonographic flow measurements had excellent interobserver reliability with an intraclass correlation coefficient (ICC) of 0.89 (p = 0.009). Technical nuances are highlighted and a brief discussion of pathology is undertaken.