Search PubMed⌕ Search

Biomedical subjects

C G Drake

Publications and source records attributed to C G Drake.

At least 19 recordsLinked to original sources
PubMed1992

Superantigens: biology, immunology, and potential role in disease.

Superantigens are unique products of bacteria and viruses which, in combination with class II major histocompatibility complex molecules, are capable of stimulating a large fraction of T cells in an affected individual. This stimulation primarily involves the variable region of the T cell receptor beta chain (V beta). The discovery of superantigens and the elucidation of their immunologic properties have provided valuable tools for the investigation of the immune system in both normal and diseased animals. Most importantly, recent work suggests that superantigens play a role in a number of diverse pathological conditions, including toxic shock syndrome and autoimmune diseases such as rheumatoid arthritis.

Animals↗
PubMed1992

Genetic and immunological mechanisms in the pathogenesis of systemic lupus erythematosus.

Recent research in systemic lupus erythematosus and animal models of lupus has provided new insight into the pathogenesis of this complex autoimmune disease. Progress has been made towards understanding the genetic contributions to disease susceptibility and induction, as well as towards elucidation of the lymphocyte abnormalities involved in pathogenic autoantibody production.

Animals↗
PubMed1991

Radical intracapsular removal of acoustic neurinomas. Long-term follow-up review of 11 patients.

Historically, the neurosurgical treatment of large acoustic neurinomas has developed with two principal goals: complete tumor removal and preservation of facial nerve function. A recent goal for small tumors is the preservation of hearing. Out of a personal series of 124 acoustic neurinomas treated over the past 35 years, the senior author has undertaken a radical intracapsular approach in 12 patients with large tumors (greater than 3 cm in diameter). Surgical indications for intracapsular removal included advanced age (five cases), the patient's wish to avoid any risk of facial paralysis (six cases), contralateral facial palsy (one case), and contralateral deafness (one case). Eleven of these 12 patients were available for follow-up review. Tumor recurrence developed in two patients (18%) at 2 and 3 years postoperatively; there were no late recurrences. Four patients died of unrelated causes, 10 to 19 years after surgery. The remaining five patients have survived a mean of 12 years since surgery without recurrence (range 3 to 22 years). Facial function was preserved in nine patients (82%). The results suggest that radical intracapsular removal may be the procedure of choice under certain circumstances and may offer an alternative to focused high-energy radiation.

Adult↗
PubMed1991

Rapid growth of residual aneurysmal neck during pregnancy. Case report.

The pregnant state has an apparently stimulatory effect on the tendency for aneurysms to grow. A patient is reported whose symptomatic aneurysm was clipped during pregnancy. The small amount of residual aneurysm underwent remarkable continued growth during the last trimester of the pregnancy. The implications for management of such cases are discussed.

Adult↗
PubMed1991

Combined endovascular embolization and surgery in the management of cerebral arteriovenous malformations: experience with 101 cases.

The authors describe their experience with 101 cerebral arteriovenous malformations (AVM's) treated by endovascular embolization followed by surgical removal. Fifty-three patients presented with intracranial hemorrhage and 35 had seizures. Based on the classification of Spetzler and Martin, two AVM's were Grade I, 13 were Grade II, 26 were Grade III, 43 were Grade IV, and 17 were Grade V. Fifty-six AVM's were in the right hemisphere, 28 were in the left hemisphere, 12 were in the corpus callosum, and five involved the cerebellum. In 50 cases, presurgical obliteration of 50% to 75% of the AVM nidus was achieved by embolization, and in 31 cases this percentage increased to between 75% and 90%. In 97 (96%) patients, complete surgical removal of the AVM was obtained. Morbidity resulting from preoperative endovascular embolization was classified as mild in 3.9% of the cases, moderate in 6.9%, and severe in 1.98%. The death rate related to embolization was 0.9%. The immediate postsurgical morbidity was classified as mild in 5.9% of the cases, moderate in 10.8%, and severe in 5.9%. The overall long-term morbidity was mild in 5.9% of the cases, moderate in 6.9%, and severe in 1.98%. Two patients (1.98%) died due to intractable intraoperative hemorrhage and two (1.98%) as a result of postsurgical pulmonary complications.

Adolescent↗
PubMed1990

Surgical treatment of unruptured aneurysms of the posterior circulation.

With the ever-increasing number of intact aneurysms revealed by modern imaging, the options for their management are assuming great importance. While some knowledge has emerged as to their natural history and the results of surgical treatment of those in the anterior circulation, little information has been published concerning unruptured aneurysms arising from the posterior circulation. The authors report their experience since 1971 with 167 patients operated on for 179 unruptured vertebrobasilar aneurysms up to 25 mm in diameter. Overall, 160 aneurysms were treated by direct clip obliteration, while 19 were managed by alternative methods. Fifty-three patients (32%) had solitary aneurysms and the other 114 patients (68%) had multiple aneurysms or an associated arteriovenous malformation, which were commonly treated concurrently. Many of these coexisting vascular anomalies had ruptured in the recent or remote past, adding to the complexity of management and interpretation of specific surgical results related to the intact posterior circulation aneurysm. There were 78 documented postoperative complications including 23 systemic complications, seven postoperative hematomas, six brain injuries from retraction, five cases of aseptic meningitis, three instances of seizures, three wound infections, and three patients with hydrocephalus. Multiple complications occurred in 23 patients. Seventy-one of the patients with these untoward events recovered, without disability, with time or treatment. There were only six poor results and one death in the series, resulting in a 4.2% combined morbidity/mortality rate. However, since two of these poor outcomes and the single death were attributable to a coexisting aneurysm, the actual surgical morbidity related specifically to the posterior circulation aneurysm was only 2.4%. This experience suggests that non-giant, intact vertebrobasilar aneurysms can be obliterated surgically at a very low risk, and this treatment should eliminate the greater lifetime risk related to an unsecured aneurysm.

Adolescent↗
PubMed1989

Combining the detachable balloon technique and surgery in imaging carotid cavernous fistulae.

Among 143 carotid cavernous fistulae, 10 cases could not be successfully treated by standard endovascular techniques alone; some form of surgical assistance was required. The circumstances included incomplete closure of the fistula while the internal carotid artery was occluded, failure to occlude the fistula after both arterial and venous endovascular approaches, hairpin loop of the cervical portion of the internal carotid artery, failure of previous trapping procedures, and failure to cure spontaneous carotid cavernous fistulae of the dural type after embolization of the external carotid feeders. These ten patients were cured by combining a surgical procedure and an interventional technique.

Adult↗
PubMed1989

Regrowth of aneurysm sacs from residual neck following aneurysm clipping.

It is recognized that incomplete treatment of an aneurysm may result in recurrent hemorrhage with serious or fatal consequences. For this reason, patients treated at the authors' institution in whom a large portion of the aneurysm neck or sac remained after application of a clip or ligature have been subjected to reoperation. However, 1- to 2-mm residual necks seen in postoperative angiography have been thought to pose little risk. Some cases of aneurysms recurring from a narrow residual neck after clipping have been reported, and a few instances of recurrent aneurysm have been described after apparently complete occlusion of the neck (as observed angiographically or in the surgeon's judgment). In recent years, a surprising number of cases have been presented in which this seemingly unimportant remnant of the neck dilated over a long period to become a dangerous aneurysm. This finding stresses the importance of complete aneurysm occlusion and of postoperative angiography for the recognition of a residual aneurysm neck. This should be important not only in aneurysm clipping but also in the endovascular treatment of intracranial aneurysms with detachable balloons.

Adolescent↗
PubMed1988

Platelet aggregation within cerebral arteriovenous malformations.

Turbulence within cerebral arteriovenous malformations (AVM's) may lead to endothelial disruption, platelet aggregation, and thrombus formation. This hypothesis would account for many of the pathological features in AVM's, including intimal hyperplasia and arterial thrombosis with or without organization. In this study, a dual-isotope method employing indium-111-labeled platelets and technetium-99m-labeled red blood cells was used to evaluate in vivo platelet aggregation in 20 patients with AVM's. The use of two isotopes allows subtraction of the blood-pool platelets and calculation of the ratio of the indium deposited:the indium in the blood pool (In(D)/In(BP)). After a 24-hour incubation period, eight of the 20 patients demonstrated platelet aggregation in their AVM's with a mean In(D)/In(BP) ration of 0.71 +/- 0.36 (+/- standard deviation). Seven of these AVM's were available for pathological study and all of them demonstrated evidence of arterial thrombosis of variable age. In the remaining 12 patients, the In(D)/In(BP) ratio was not significantly elevated (mean 0.02 +/- 0.13), indicating the absence of active platelet aggregation during this short interval of study. Five of these AVM's were pathologically examined, four of which showed evidence of arterial occlusion. It is concluded that platelet aggregation is a common occurrence in cerebral AVM's and may account for the dynamic histopathology often seen in these lesions.

Adult↗
PubMed1987

Use of detachable balloons for proximal artery occlusion in the treatment of unclippable cerebral aneurysms.

Of 68 patients with unclippable aneurysms treated by proximal artery occlusion with detachable balloons, permanent occlusion was achieved in 65; of these patients, 37 had carotid artery aneurysms below the origin of the ophthalmic artery, 21 had aneurysms arising from the supraclinoid portion of the carotid artery, six had basilar trunk aneurysms, and one had a distal vertebral aneurysm. Examination for treatment selection included assessment of the circle of Willis by compression angiography and xenon blood flow studies, with the ultimate evaluation being test occlusion under systemic heparinization with the balloon temporarily placed in the desired position. Of 67 patients who underwent a formal occlusion test, eight with carotid artery aneurysms did not initially tolerate the occlusion test, and ischemic signs disappeared instantaneously with deflation and removal of the balloon. During test occlusion, two additional patients had ischemic events that proved to be embolic; these reversed immediately upon balloon deflation. Of the 65 patients in whom permanent occlusion was effected by detachable balloon, there were nine instances of delayed cerebral events. One of these was a seizure leading to respiratory arrest and resuscitation 3 days following occlusion in a patient who had presented with seizures. The other eight cases were delayed ischemic events; seven were completely reversed and one patient had residual weakness in one leg (1.5% permanent morbidity). Extracranial-intracranial bypass procedures were performed in 25 of the 65 cases. All aneurysms of the carotid artery below the level of the ophthalmic artery presented angiographic proof of complete thrombosis. Ten of 21 aneurysms arising from the supraclinoid portion of the carotid artery were completely thrombosed by proximal occlusion alone, without additional trapping procedures. Similarly, in three of six basilar trunk aneurysms, proximal occlusion alone initiated complete aneurysm thrombosis without trapping. The conclusion is that proximal balloon occlusion for unclippable cerebral aneurysms is a convenient, safe, and effective way of producing arterial occlusion in these cases.

Carotid Artery Diseases↗
PubMed1987

Giant intracranial varices secondary to high-flow arteriovenous fistulae.

An intracranial varix is rare and has been associated mostly with vein of Galen fistulae or arteriovenous (AV) malformations. The authors present eight cases of intracranial, pial or subpial AV fistulae with concomitant giant varices. Six were supratentorial and two were infratentorial. Only one case involved the vein of Galen. In six cases successful surgical and/or endovascular occlusion of the intracranial AV fistula was obtained, and one case was treated conservatively. Staging of surgery and postoperative hypotension were considered to be important in avoiding edema and hemorrhage following obliteration of a large AV shunt. One patient died from delayed postoperative intracerebral bleeding.

Adolescent↗