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C Shrontz

Publications and source records attributed to C Shrontz.

9 recordsLinked to original sources
PubMed1986

Surgical correction of lesions affecting the second portion of the vertebral artery.

Substantial controversy has surrounded the diagnosis and management of vertebrobasilar ischemic events, with no consensus on the value of medical or surgical treatment of patients symptomatic with brain stem ischemia who have angiographically proven vertebral artery lesions. This report presents our experience with the surgical treatment of 12 of 88 patients with angiographically verified lesions in the vertebral artery who were symptomatic for 1 to 12 months before their evaluation. None experienced symptomatic relief with antiplatelet agents, nor did the administration of anticoagulants in 4 of the patients provide any benefit. The lesions included bilateral vertebral artery occlusion with distal reconstitution through muscular collaterals in 6 patients, unilateral vertebral artery hypoplasia with contralateral long-tailed lesions from the vertebral artery origin to C-5 in 3 patients, and severe bilateral vertebral artery origin lesions extending beyond the C-5 level in 3 patients. A vertebral endarterectomy and vertebral-carotid transposition in the second portion of the artery were successfully used to reestablish flow and obtain symptomatic relief in 10 of the 12 cases; 1 of these procedures had to be redone because of a persistent stenosis at C-4. Another patient had a saphenous vein graft from the common carotid to the vertebral artery at C-5. The remaining patient had an anastomosis of the distal external carotid to the vertebral artery at C-3, but this failed and an anastomosis of the occipital artery to the anterior inferior cerebellar artery had to be completed to reestablish flow.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1986

Surgical anatomy of the arteries of the posterior fossa.

The development of revascularization for vertebrobasilar ischemic events has created a need to identify the best sites at which to perform bypass procedures. Since the occlusive process may selectively affect various levels of the vertebrobasilar tree, sites in different vessels must be used to reestablish flow distal to the area of occlusion. Twenty-seven unfixed human brains were obtained 4 to 8 hours post mortem, and the vertebrobasilar system was injected with polyester resin. Under a surgical microscope the outer diameter, length, and site of origin of major branches were recorded for the following arteries: vertebral, basilar, posterior inferior cerebellar (PICA), anterior inferior cerebellar (AICA), superior cerebellar (SCA), and posterior cerebral (PCA). The ideal sites for an anastomosis were identified as the pretonsillar segment of the PICA, the second portion of the AICA, the perimesencephalic segment of the SCA, and the perimesencephalic part of the PCA. Based on the anatomical observations reported here, these were the best sites because of their outer diameter, degree of mobility, least number of branches, and frequency of occurrence. Use of two of these arteries, however, may pose potential problems: although the PCA has an ideal outer diameter, it also has numerous branches to the brain stem in its most accessible site in the perimesencephalic area; and the PICA is not consistently present, being found in only 75% of the 27 specimens studied.

Basilar Artery↗
PubMed1985

Acute inflammation and endothelial injury in vein grafts.

An experimental study of autogenous vein graft morphology 6 hours after arterial implantation was performed in dogs. The animals were divided into five groups. The first control group had veins harvested and stored but not implanted. The endothelium showed excellent preservation by routine histology and scanning electron microscopy. The second control group had grafts implanted and flow decreased to 30 to 50 ml/minute. There was a massive acute inflammatory response with subendothelial and transmural accumulation of neutrophils causing widespread endothelial sloughing. A third group had grafts implanted, but flow was not reduced (mean, 170 ml/minute). Although an inflammatory response was also present, it was much less severe than in the low flow grafts and the endothelium remained grossly intact. Two other groups had low flow grafts implanted, but were treated with either lidocaine or steroids. Lidocaine had no effect on the inflammatory response or endothelial injury. High doses of alpha-methylprednisolone succinate almost completely prevented both endothelial loss and inflammatory infiltration. This study supports the premise that an acute inflammatory response can initiate endothelial injury after autogenous grafting, an effect that is much more prominent in low flow than high flow grafts. It also demonstrated that steroids can almost totally suppress the injury during the initial 6 hours after implantation.

Animals↗
PubMed1984

Aggressive choroid plexus papilloma.

A young woman, who was initially treated for an Arnold-Chiari malformation, was found 7 years later to have a posterior third ventricular tumor. A superior cerebellar approach allowed total resection of the mass, which was an aggressive choroid plexus papilloma. The patient was treated with whole cerebrospinal axis radiation. There is no clinical or computed tomographic evidence of recurrence after 4 years. The literature is reviewed and a discussion of aggressive choroid plexus papilloma (carcinoma) is presented.

Adult↗
PubMed1984

Surgical reconstruction of the proximal vertebral artery.

The authors have reviewed their experience in the management of 55 patients admitted to Henry Ford Hospital with symptoms of vertebrobasilar insufficiency and associated proximal vertebral artery stenosis or occlusion. In 48 patients, the symptoms occurred as multiple repeated events, five of which resulted in permanent deficits. The remaining seven patients had single events, four of which caused permanent deficit. These patients had been treated unsuccessfully with antiplatelet agents (37 cases) and with anticoagulant drugs (15 cases) before surgery. Most patients had multiple angiographic abnormalities, including bilateral vertebral stenosis in 19 cases, unilateral vertebral stenosis and contralateral occlusion in 18, unilateral vertebral hypoplasia and contralateral stenosis in 10, subclavian artery stenosis with steal in seven, and bilateral vertebral artery occlusion in one case. Posterior communicating arteries could not be demonstrated angiographically in 18 patients. Thirty-four patients had associated stenotic or occlusive lesions of the internal carotid artery. Forty-eight underwent a vertebral-to-carotid artery transposition. Of these, 18 had an associated carotid endarterectomy and seven had a vertebral artery endarterectomy immediately before the transposition. Two patients had saphenous vein grafts, one from the subclavian and one from the common carotid artery to the vertebral artery. Other surgical procedures included vertebral artery ligation in one case, transposition of the vertebral artery to the thyrocervical trunk in two cases and to the subclavian artery in one case, and endarterectomy of the origin of the vertebral artery in one case. All but two patients had complete resolution of their symptoms: one had persistent dizziness and the other had syncopal episodes. Complications included transient Horner's syndrome (30 cases) which became permanent in four cases, vocal cord paralysis (three cases), elevated hemidiaphragm without respiratory difficulty (two cases), and superficial would infection (one case). There were no deaths. Although the presentation of patients with vertebrobasilar insufficiency is generally characteristic, we believe that a specific diagnosis can be established only by angiographic means. Anticoagulants have been used to alleviate symptoms in some cases but are ineffective in solving the primary hemodynamic problem. Surgical reconstruction of the affected area deserves further evaluation in the management of these patients.

Adult↗
PubMed1983

Combined reconstruction of the vertebral and carotid artery in one single procedure.

Patients suffering from vertebrobasilar insufficiency frequently have multiple areas of involvement in the extracranial circulation. Eight patients admitted to Henry Ford Hospital had symptoms suggestive of vertebrobasilar insufficiency and angiograms showing multiple abnormalities. A combined operation that reconstructed the carotid and vertebral circulations in one single procedure was completed in all patients with minimal morbidity and no mortality. The surgical procedure is described in detail.

Aged↗
PubMed1982

Histological structural abnormalities of superficial temporal arteries used for extracranial-intracranial anastomosis.

Histological evaluation of the superficial temporal artery resected at the time of extracranial-intracranial anastomosis was performed in 64 consecutive patients. A neuropathologist who was not aware of the medical condition of these patients studied all specimens under light microscopy with hemotoxylin and eosin, Verhoff, and Mallory strains. Intimal proliferation was observed in 62 samples, intimal fibrosis in 56, fragmentation of the internal elastic lamina in 45, splitting of the internal elastic lamina in 41, fragmentation of the media in 38, and fragmentation of the minimal external elastic tissue in 17. Stenosis of the vessel was observed, and graded from 0% to 50%, with a mean of 20%. The development of intraluminal stenosis was considered to be secondary to the development of intimal fibrosis and hyperplasia. The changes observed were progressive and conformed with those previously described; there was no evidence of correlation with sex, diabetes, or hypertension. The implications for the development of occlusion of the anastomosis or stroke, and for patient survival are discussed.

Adolescent↗