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Dive into the research topics where Robert L. Tomsak is active.

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Featured researches published by Robert L. Tomsak.


American Journal of Ophthalmology | 1984

Structural factors in the pathogenesis of ischemic optic neuropathy.

Richard H. Feit; Robert L. Tomsak; Carl Ellenberger

Some patients with nonarteritic ischemic optic neuropathy have no signs or symptoms of systemic vascular disease; therefore, nonvascular factors may play a role in the pathogenesis of this syndrome. We observed that the average cup-disk ratio of the unaffected optic disks in a group of patients with ischemic optic neuropathy was significantly (P = .005) smaller than the average ratio in a group of age-matched controls (0.36 +/- 0.19 vs 0.21 +/- 0.16). Fourteen of 30 patients but only two of 29 controls had cup-disk ratios equal to or less than 0.1. Mechanical factors, such as constriction of axons as they traverse the scleral canal, may contribute to the pathogenesis of ischemic optic neuropathy.


Neurology | 1982

Ischemic optic neuropathy A complication of cardiopulmonary bypass surgery

Patrick J. Sweeney; Anthony C. Breuer; John B. Selhorst; Edward A. Waybright; Anthony J. Furlan; Richard J. Lederman; Maurice R. Hanson; Robert L. Tomsak

Ischemic optic neuropathy followed cardiopulmonary bypass surgery in the postoperative period in 7 of 7685 consecutive procedures. The visual loss was unilateral in four patients and bilateral in three and there was little improvement. This ischemic infarction of the optic nerve disk was attributed to hypotension, hypothermia, and activation of certain complement factors by the bypass procedure.


Ophthalmology | 1985

Ocular and orbital toxicity following intracarotid injection of BCNU (carmustine) and cisplatinum for malignant gliomas

Daniel F. Miller; Janet W. Bay; Richard J. Lederman; Joseph D. Purvis; Lisa R. Rogers; Robert L. Tomsak

Eleven patients treated with intracarotid BCNU, cisplatinum, or BCNU and cisplatinum in combination for recurrent malignant gliomas were followed with serial ophthalmologic examinations for 2 to 11 months. Eight patients developed significant visual loss ipsilateral to the side of infusion. Secondary glaucoma and internal ophthalmoplegia were new complications observed after BCNU treatment. An unusual pigmentary retinopathy, previously unreported, was seen in patients treated with cisplatinum. One patient also developed a cavernous sinus syndrome after the intracarotid administration of cisplatinum.


Otolaryngology-Head and Neck Surgery | 1983

Autoimmune reactivity in Cogan's syndrome: A preliminary report:

Gordon B. Hughes; Sam E. Kinney; Barbara P. Barna; Robert L. Tomsak; Leonard H. Calabrese

Autoimmune inner ear disease was first described by McCabe in 1979. The diagnosis is supported by cell-mediated immune responses to inner ear membrane antigen stimulation. Cogans syndrome consists of vestibuloauditory dysfunction, ocular inflammation, and nonreactive serologic tests for syphilis. The ocular disease can be controlled by steroids; unfortunately, some patients ultimately become totally deaf. An autoimmune etiology has long been suspected but only recently confirmed by McCabe. In our study two patients with Cogans syndrome were studied for autoimmune inner ear disease with the use of both cellular and humoral immune tests. Results were compared to normal control subjects. On the basis of test results, preliminary conclusions were that (1) the vestibuloauditory symptoms of Cogans syndrome are autoimmune in origin; (2) the autoimmune process is mediated through cellular rather than humoral (antibody) pathways; (3) systemic steroids may suppress positive test results; and (4) test results are more likely to be positive when symptoms are acute. Therapeutic implications are significant: the addition of cytotoxic drugs to steroids in selected cases may help prevent total deafness that otherwise might be inevitable.


American Journal of Ophthalmology | 1983

A retrospective review of 26 cases of dysthyroid optic neuropathy

Gregory J. Panzo; Robert L. Tomsak

Sixteen patients (14 women and two men) with dysthyroid optic neuropathy (26 involved eyes) were treated with either oral corticosteroids, orbital irradiation, surgical orbital decompression, combined corticosteroids and irradiation, or combined corticosteroids and surgical decompression. Thirteen of 16 eyes responded favorably to corticosteroid therapy but eight of the 13 relapsed upon discontinuation of treatment. Two of four eyes responded to irradiation initially but later relapsed. The response to orbital decompression was almost uniformly beneficial (eight of nine eyes responded) and lasting in all. Combined modes of therapy offered no additional advantage.


Survey of Ophthalmology | 1986

Magnetic resonance images in a case of “divergence paralysis”

Robert M. Stern; Robert L. Tomsak

The clinical syndrome of divergence paralysis has been described since the mid 19th century. Speculation still surrounds the possible existence of an anatomical center for divergence function. Our report explores this possibility and describes the magnetic resonance images of a patient with a unilateral 6th nerve palsy who later developed the clinical picture of divergence paralysis.


Neurosurgery | 1985

Improvement in the retinal circulation after superficial temporal to middle cerebral artery bypass.

Michael Standefer; John R. Little; Robert L. Tomsak; Anthony J. Furlan; Hernando Zegarra; George W. Williams

The retinal circulation of 35 patients (age, 30 to 71 years) with symptomatic internal carotid occlusion (22 cases) or severe inaccessible stenosis (13 cases) was studied both before and after superficial temporal to middle cerebral artery (STA-MCA) bypass surgery using ophthalmodynamometry (ODM) and intravenous fundus fluorescein angiography (IVFA). Ninety-four per cent of the patients were found preoperatively to have funduscopic findings or symptoms indicative of ocular ischemia. ODM values were abnormal preoperatively in 32 of 35 patients (91%), and improvement in ODM values for the ipsilateral eye was noted postoperatively in 25 patients (71%). ODM values obtained during the early (less than 3 months) and late (greater than 3 months) postoperative periods were significantly improved when compared to the preoperative values. IVFA values were abnormal in 25 of 29 patients (86%) preoperatively, and significant improvement was noted in 22 of 25 patients (88%) postoperatively. Preoperative patients with normal fundus examinations (10 cases) had significantly better values for IVFA and ODM than patients with venous stasis retinopathy. The findings of the study showed that STA-MCA anastomosis is beneficial in treating retinal ischemia secondary to ipsilateral severe inaccessible carotid artery stenosis or occlusion.


Cancer | 1991

Alternating Sequential Intracarotid BCNU and Cisplatin in Recurrent Malignant Glioma

Lisa R. Rogers; Joseph B. Purvis; Richard J. Lederman; Scott A. Rosenbloom; Robert L. Tomsak; Melinda L. Estes; Michelle Magdinec; Sharon V. Medendorp; James M. Boyett

The authors entered 43 patients with recurrent malignant glioma in a trial of alternating sequential intracarotid BCNU and cisplatin. Protocol design was alternating courses of BCNU (2 doses, 300 to 400 mg each) and cisplatin (2 doses, 150 to 200 mg each) each at 4‐week to 6‐week intervals. Eight of 40 patients (20%) evaluable after the first course of BCNU showed partial or minor response. Only 18 patients were evaluable after the first course of cisplatin, and 5 were evaluable after the second course of BCNU. Median survival was 9 months (range, 2 weeks to 6 years). Cerebral or ocular toxicity unique to this method of chemotherapy administration and failure to show clinical improvement were the most common reasons for removal from study. Because of the high attrition rate, the authors were unable to determine a meaningful response to alternating sequential BCNU and cisplatin or to test the clinical degree of cross‐resistance to these agents in human malignant glioma.


Neurosurgery | 1986

Retinal artery pressure and cerebral artery perfusion pressure in cerebrovascular occlusive disease.

John R. Little; Robert L. Tomsak; Zeyd Ebrahim; Anthony J. Furlan

The objectives of the investigation were to measure the retinal artery pressure (RAP) and cortical artery pressure (CAP) in patients undergoing superficial temporal artery to middle cerebral artery (STA-MCA) bypass, to study the relationship between these pressures, and to evaluate our ability to predict CAP on the basis of RAP. The 44 patients undergoing bypass surgery included 26 with ipsilateral internal carotid artery (ICA) occlusion (Group I), 5 with bilateral ICA occlusion (Group II), 4 with inaccessible ICA stenosis proximal to the ophthalmic artery (OA) (Group III), 2 with ICA stenosis distal to the OA (Group IV), 3 with ICA occlusion distal to the OA (Group V), 2 with MCA stenosis (Group VI), and 2 with MCA occlusion (Group VII). Five patients undergoing craniotomy for an asymptomatic saccular aneurysm were used as controls. Mean RAP (MRAP) was measured by ophthalmodynamometry (ODM) and was expressed as a ratio of the mean systemic arterial blood pressure (i.e., MRAP/MSAP). The mean MRAP/MSAP for combined Groups I, II, and III with ICA occlusion proximal to the OA was significantly lower than both the control group (P = 0.0001) and the combined Groups IV, V, VI, and VII with occlusive lesions distal to the OA (P = 0.0001). Six patients in Groups I and II with venous stasis retinopathy had a mean MRAP/MSAP of 0.18 +/- 0.11. Mean cortical artery pressure (MCAP) was measured by inserting a 26 gauge needle into a small cortical artery and was expressed as the MCAP/MSAP ratio. Mean MCAP/MSAP was less than 0.50 for all groups except Group III.(ABSTRACT TRUNCATED AT 250 WORDS)


Neuro-Ophthalmology | 1989

Familial ophthalmoplegia-plus syndrome with corneal endothelial disorder

Gregory S. Kosmorsky; David M. Meisler; Leslie R. Sheeler; Robert L. Tomsak; Patrick J. Sweeney; Hiroshi Mitsumoto; Scott MacRae

The authors report two brothers with an ophthalmoplegia-plus syndrome characterized by chronic progressive external ophthalmoplegia associated with hypogonadism, primary testicular failure, neural deafness, cone-rod degeneration and mild optic atrophy. One brother, the proband, was a daily soft contact lens wearer who developed persistent epithelial and stromal edema of the right cornea and had bilaterally thickened corneas by ultrasonic pachymetry. Endothelial studies of both brothers revealed marked polymegathism, and pleomorphism. Stressing the inherently abnormal endothelium with contact lens wear may have resulted in further endothelial compromise and corneal edema in the proband.Endothelial abnormalities may be another clinical finding within the spectrum of ophthalmoplegia-plus syndrome and should be searched for before fitting these individuals with contact lenses.

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Anthony J. Furlan

Case Western Reserve University

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