✓ The authors describe their experience using booster clips to secure the closure of primary clips in the repair of giant and other thick-walled aneurysms. These clips were used for 21 aneurysms in 20 patients, comprising 12% of all aneurysms operated on during the 15-month period of the report, but representing about 50% of all giant aneurysms operated on during the same time frame. These clips are designed to encircle the primary clip and have fixation “shoes” to close upon the jaws of the primary clip. All aneurysms were opened for decompression and thrombectomy when necessary following temporary major vessel occlusion before placement of the primary clip. Cerebral blood flow measurements and continuous electroencephalographic monitoring were utilized to predict the brain's tolerance to temporary ligation of the internal carotid artery (ICA) in those cases with a giant aneurysm arising from that vessel. There were no complications attributable to the periods of intracranial or cervical ICA occlusion; these periods varied but did not exceed 8 minutes for the former nor the tolerance period for the latter, which was calculated as from 5 to 30 minutes. It was necessary to reoperate on two patients and reposition clips because of stenoses or occlusions identified on immediate postoperative angiography. Fifteen patients had normal neurological function at the time of discharge. Three patients had minor deficits which did not prevent employment; two of these were related to a preoperative deficit and one was a complication of delayed ischemia. There were two deaths: one from bleeding complications and probable damage to perforating vessels in a patient operated on under profound hypothermia (the only case in the series so managed), and one from respiratory complications in a patient with severe pulmonary problems.
Thoralf M. Sundt Jr., David G. Piepgras and W. Richard Marsh
Douglas Chyatte, Nancy Rusch and Thoralf M. Sundt Jr.
✓ Severe chronic cerebral vasospasm was reliably induced in dogs by two injections, 2 days apart, of autologous blood into the cisterna magna. Treatment with ibuprofen or high-dose methylprednisolone after the first injection prevented or reduced vasospasm. Both drugs reduced meningismus and accelerated the rate of neurological recovery. Compared with specimens from normal dogs, rings of basilar arteries obtained from untreated dogs contracted weakly in response to 5-hydroxytryptamine, prostaglandin F2α, potassium chloride, and barium chloride. Rings of arteries from dogs who received ibuprofen or methylprednisolone contracted more strongly. Electron micrographs of basilar arteries from untreated dogs showed degeneration of smooth muscle, whereas those from treated dogs did not. Thus, what is termed “chronic cerebral vasospasm” probably represents a structural derangement of the blood vessel wall leading to its narrowing, rather than a sustained contraction of the vascular smooth muscle. Administration of high-dose methylprednisolone and ibuprofen can prevent its occurrence.
Thoralf M. Sundt Jr., J. Keith Campbell and Otis W. Houser
✓ Two cases are reported in which anastomotic procedures between the posterior cerebral and superior cerebellar arteries were useful for the management of occlusive and aneurysmal disease of the posterior circulation. Operative procedures such as these may play a role in the future management of vascular problems in this system.
Marc R. Mayberg, O. Wayne Houser and Thoralf M. Sundt Jr.
✓ Scanning electron microscopy of feline basilar arterial endothelium 4 hours and 1, 3, 5, and 7 days after subarachnoid hemorrhage (SAH) showed longitudinal furrows that correlated with angiographically demonstrated vasospasm. These ridges persisted after fixation at physiological pressure, and probably reflected medial contraction with undulation of the underlying elastic lamina. No change in endothelial cell morphology or thrombogenesis was observed as long as 7 days after SAH. There is no evidence from this study to suggest that ischemia from vasospasm is a product of thromboembolism from damaged endothelial surfaces.
Thoralf M. Sundt Jr., William C. Grant and Julio H. Garcia
Fredric B. Meyer, Thoralf M. Sundt Jr. and Bruce W. Pearson
✓ Carotid body tumors are a rare but potentially difficult surgical entity. Their pathology, physiology, and natural history are reviewed along with surgical results reported in the literature. A surgical approach for removal of these tumors is presented which differs significantly from the recommended techniques in that emphasis is placed on intraoperative monitoring of cerebral blood flow, the selective use of shunts, a tumor-adventitial plane of dissection, preservation of the carotid artery complex, and mobilization of the parotid gland. Thirteen cases using these techniques are reviewed. The mortality rate and the incidence of cerebrovascular sequelae were both 0%. The major morbidity consisted of injury to the lower cranial nerves in five patients (39%) with tumors larger than 5 cm in length.
Phyo Kim, James D. Jones and Thoralf M. Sundt Jr.
✓ High-energy phosphate levels were measured in the canine cerebral artery during chronic vasospasm. Subarachnoid hemorrhage and vasospasm were induced by percutaneous injections of autologous venous blood into the cisterna magna. Narrowing of the artery was confirmed by angiography 7 days later. Levels of adenosine phosphates (adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP)), guanosine phosphates (guanosine triphosphate (GTP) and guanosine diphosphate (GDP)), and creatine phosphate (CrP) in the basilar artery were quantified using high-performance liquid chromatography. The total creatine (Crtotal) content was measured by a spectrophotometric method after acid hydrolysis of CrP. Levels of ATP, GTP, and CrP were markedly reduced in the spastic arteries, and ratios of ATP:ADP, GTP:GDP, and CrP:Crtotal were significantly decreased. The results indicate a serious disturbance in the energy metabolism that takes place in the cerebral artery during chronic vasospasm.
S. V. Ramana Reddy and Thoralf M. Sundt Jr.
✓ A case of giant traumatic false aneurysm of the intracranial internal carotid artery (ICA) with a concomitant carotid-cavernous fistula is reported. The fistula and the aneurysm persisted after ipsilateral cervical ICA ligation was performed elsewhere. Successful obliteration of the aneurysm and the fistula, with preservation of cross filling of the ipsilateral middle cerebral artery system, was accomplished by ligation of the intracranial ICA proximal to the origin of the posterior communicating artery with a 7–0 prolene suture, followed by transaneurysmal packing of the fistula.
Thoralf M. Sundt Jr., Arthur G. Waltz and George P. Sayre
Clifford R. Jack Jr., Thoralf M. Sundt Jr., Nicolee C. Fode and Dale G. Gehring
✓ Between 1974 and 1982, an anastomosis between a pedicle of the superficial temporal artery (STA) and a cortical branch of the middle cerebral artery (MCA) was performed in 163 carotid systems in 157 patients for internal carotid artery occlusion in whom postoperative angiograms were available for analysis. The angiographic opacification of the arterial system was correlated with the patient's preoperative neurological function and stroke in the follow-up period.
From this analysis, the following observations were made: 1) 96% of bypasses were patent; 2) 80% of bypasses achieved a high or medium MCA filling score; 3) there was hypertrophy of the STA in 70% of the cases; 4) greater bypass filling occurred in hemispheres with nonvisualized preoperative collateral circulation than in those with readily visualized collateral flow; 5) a meaningful correlation between angiographically assessed postoperative bypass function and stroke rate was not possible because only four patients suffered an ipsilateral hemispheric stroke in the 8-year follow-up period; and 6) patients who were neurologically unstable before the procedure were at greatest risk for a stroke in the follow-up period. It is apparent that objective analysis of the effectiveness of an STA-MCA bypass, or any other form of extracranial bypass, must await the development of new diagnostic studies in which high-resolution three-dimensional quantification of cerebral blood flow is possible. These studies will necessarily be correlated with preoperative and follow-up clinical data.