Arterial bypass surgery using a spontaneously formed "bonnet" superficial temporal artery in a patient with symptomatic common carotid artery occlusion: case report.

BACKGROUND

Common carotid artery (CCA) occlusive disease may cause hemodynamic cerebral ischemia resulting in the development of ischemic symptoms. The blood flow in the superficial temporal artery (STA) ipsilateral to the occluded CCA is usually poor, which limits its use as a donor artery for extracranial-intracranial arterial bypass surgery.

CLINICAL PRESENTATION

Despite antiplatelet therapy, recurrent transient ischemic attacks manifesting as motor aphasia developed in a 72-year-old man. Neuroradiological imaging revealed misery perfusion in the bilateral cerebral hemispheres caused by left CCA occlusion and right internal carotid artery occlusion. Blood flow from the STA contralateral to the occluded CCA perfused the ipsilateral STA over the midline in a retrograde fashion.

INTERVENTION

After confirming the direction and the pressure of the blood flow in the spontaneously formed "bonnet" STA, the STA was anastomosed to a cortical artery in the symptomatic frontal lobe so that blood flow in the ipsilateral STA was supplied from the contralateral STA. The procedure was accomplished without difficulty, and no further ischemic symptoms developed after surgery. Postoperative cerebral angiography demonstrated an increase in collateral flow to the anastomosed bonnet STA and perfusion to an entire territory of the upper trunk of the symptomatic middle cerebral artery via the anastomosis.

CONCLUSION

This case suggests that arterial bypass surgery can be performed using a spontaneously formed bonnet STA as a donor in a patient with symptomatic CCA occlusion.