Histological changes in vessels used for microvascular reconstruction in the head and neck.

Recipient vessels from the head and neck region were histologically examined in 30 patients who had undergone extensive tumor resection necessitating microvascular tissue reconstruction. Past illnesses considered to be risk factors included hypertension, myocardial disease, lung disease, cirrhosis, diabetes, nephritis, as well as extensive nicotine and alcohol abuse. Blood vessels chosen for microsurgical anastomosis were exclusively examined histologically in this study. Patients undergoing microvascular surgery demonstrated vessel abnormalities in 93%. The frequency of dysplasia was higher in the arteries than in the veins (73% and 26%, respectively). Marked thickening of the blood vessel wall and severe exfoliation of the endothelial cells were observed in most arteries. Fibrodysplasia and exfoliated endothelial cells were more frequently observed in the recipient arteries than the graft arteries. Only slight thickening of the vessel wall and mild fibrodysplasia were seen in the veins. Two graft failures were correlated to technical errors rather than pre-existing vessel lesions. This study revealed that most patients undergoing microsurgery in the head and neck region demonstrate pre-existing damage in vessels, which generally hinders anastomosis. Although the study tried to identify fully the interrelationships between the extent of dysplasia, past medical history, preoperative therapy, risk factors and factors that cause free-graft failure, pre-existing changes in the recipient and graft vessels may cause technical difficulties and must be regarded as additional factors contributing to graft failure.