CPT® Code 37606

The procedure described by CPT® Code 37606 involves the ligation of the internal or common carotid artery using a method known as gradual occlusion, which is facilitated by specialized clamps such as the Selverstone or Crutchfield clamp. This surgical intervention is performed to manage conditions affecting cerebral blood flow, particularly when there is a need to evaluate and control blood supply to the brain. The process begins with an incision over the carotid artery bifurcation, allowing the surgeon to dissect through the soft tissues to access both the common and internal carotid arteries. A critical step in this procedure is the puncturing of the internal carotid artery to insert a pressure recording device, which is advanced toward the base of the skull. This device is essential for monitoring internal carotid pressures throughout the procedure, ensuring that cerebral perfusion is adequately assessed. The common carotid artery is typically the preferred site for ligation; however, if cerebral blood flow is found to be inadequate, the internal carotid artery may be targeted instead. The gradual occlusion technique involves the careful application of the clamp to reduce blood flow incrementally, allowing for close monitoring of the patient's neurovascular status. This method is particularly beneficial as it provides a controlled approach to occlusion, which can be adjusted over several days, ensuring that the patient can tolerate the changes in blood flow before finalizing the ligation.