A case of radiation induced aneurysm of extracranial carotid artery

An unusual case of post-irradiation aneurysm of extracranial internal carotid artery is presented. A 70-year-old man, complaining of left cervical throbbing mass with focal pain, was admitted on February 8, 1985. It was noted, from his past history, that he had had surgery of the removal of cervical lymphnodes and that unknown dosage of irradiation had been added to the cervical region 30 years before. Left carotid angiography (on admission) demonstrated a giant aneurysm in the cervical portion of internal carotid artery. Right carotid angiography with compression of left carotid artery revealed good cross filling through anterior communicating artery. Computed tomography with contrast media showed a ring like enhanced mass, which was thought to suggest that a large part of the aneurysm was filled with intraluminal thrombosis. During 30 days of evaluation, the aneurysm grew larger and his cervical pain became untolerable. Operation, the resection of the aneurysm and the reconstruction (of circulation) with vein graft, was challenged on March 12. It was so difficult with meticulous work that the ligation of left common carotid artery was performed after all. Seven days after the operation, he suffered from the gastrointestinal bleeding, which was enough to lead him to hypovolemic shock. Thereafter, right hemiparesis and aphasia were brought about. Two months later, he died of pneumonia. On histological examination, it was demonstrated that the aneurysm communicated with the necrotic tissue and that the normal structure of the blood vessel was not observed in the aneurysmal wall and consisted of the collagenous fiber and granulated tissue. The aneurysm was interpreted as a false one. (author)