COLLATERAL channels usually develop in patients with extracranial arterial occlusive disorders which help to keep blood flow constant. Although several radiological studies in man have documented collateral channels, few experimental studies have been performed to elucidate changes in arterial collateral patterns and blood flow distribution in cervical arteries in response to occlusion of a vessel in the neck or chest. This report details the results of an analysis of the collateral channels that develop in response to long standing occlusion of the right subclavian artery proximal to the origin of the right vertebral artery.
Methods
Sixteen mongrel dogs were involved in the present study. Five were used for normal control subjects. In 11 dogs, the right subclavian artery was ligated just proximal to the origin of the right vertebral artery. The animals were allowed to live for from six months to four years. During this time, other hemodynamic studies