Indocyanine Green and Contrast-enhanced Ultrasound videoangiography : a synergistic approach for real time verification of distal revascularization and aneurysm occlusion in a complex distal middle cerebral artery aneurysm

BACKGROUND: Distal outflow occlusion and extracranial-intracranial bypass represent a possible option for the surgical management of complex middle cerebral artery (MCA) aneurysm. A limitation of distal clipping strategy combined to bypass relies on the difficulties in predicting intraoperatively the good blood flow supply to the brain territory distal to the aneurysm and the extent and speed of aneurysmal thrombosis. METHODS: The authors presented an innovative approach in which Contrast-enhanced US (CEUS) and indocyanine green video-angiography (ICG-VA) have been synergistically used to study the effect of distal clipping on the aneurysm flow and the parenchymal blood flow after the bypass. They used this approach in a patient harboring a fusiform, partially thrombosed distal left MCA aneurysm. RESULTS: The patient was treated by a superficial temporal artery-middle cerebral artery bypass, followed by MCA clipping immediately distally to the aneurysm. ICG-VA was used to evaluate bypass patency and brain perfusion in the area supplied by the bypass. CEUS was used to confirm the characteristics of the aneurysm and to explore the proximal MCA compartment immediately after dural opening, and to verify in real-time the effect on aneurysm flow determined by distal outflow occlusion. Post-operative imaging confirmed aneurysm occlusion and patency of the bypass. The patient did not experience any neurological sequelae. CONCLUSIONS: The authors wanted to highlight the first report of a synergistic intraoperative utilization of ICG-VA and CEUS in studying parenchymal perfusion and aneurysms flow in complex neurovascular procedures.