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Biomedical subjects

R C Sergott

Publications and source records attributed to R C Sergott.

At least 109 records · Page 6Linked to original sources
PubMed1988

Positron emission tomography in a patient with progressive multifocal leukoencephalopathy.

A 56-year-old man with chronic lymphocytic leukemia, progressive multifocal leukoencephalopathy, and a dense left homonymous hemianopia had 18F-fluorodeoxyglucose positron emission tomography. Cortical glucose metabolism was decreased in the right cerebral hemisphere and the left cerebellar hemisphere. To our knowledge, this is the first demonstration of cerebral and cerebellar hypometabolism due solely to white matter disease.

Aged↗
PubMed1988

Antibody to myelin-associated glycoprotein produces central nervous system demyelination.

Antibodies to myelin-associated glycoprotein (MAG) have been implicated in certain human demyelinating diseases of the peripheral nervous system. In the present study, a monoclonal antibody to MAG with 20% guinea pig serum (GPS) was injected into mammalian optic nerves and produced in vivo demyelination associated with three ultrastructural patterns of myelin injury: (1) widened lamellae; (2) myelin vesiculation; and (3) cell-associated myelin damage. These patterns of myelin injury have been observed neuropathologically in MS and in a demyelinating peripheral neuropathy associated with plasma cell dyscrasias. Demyelination was not observed in nerves injected with anti-MAG and heated GPS or a monoclonal antibody to chick myoblasts and 20% GPS. These results establish the ability of anti-MAG to produce in vivo demyelination of mammalian CNS and indicate that a single antibody directed against a specific myelin component may initiate multiple types of myelin damage.

Animals↗
PubMed1988

Resolving metabolic abnormalities in a case of pure alexia.

We report resolving metabolic abnormalities corresponding to clinical improvement in a patient with pure alexia secondary to acute cerebral infarction. Local cerebral glucose metabolism (lCMRgl) was measured with positron emission tomography (PET) using 18F-fluorodeoxyglucose (18F-FDG) close to ictus and 4 1/2 months later. Serial CTs and a subsequent MRI demonstrated small, unchanging left-hemispheric lesions involving the area of the lateral geniculate body and the splenium of the corpus callosum. PET demonstrated the evolution of the metabolic abnormality resulting from intrahemispheric (lateral geniculate) and interhemispheric (splenium) disconnection in the absence of occipital lobe infarction. This case illustrates that cerebral disconnection can result in the syndrome of pure alexia. The factors accounting for focal hypometabolism in the absence of cerebral infarction are discussed.

Brain↗
PubMed1988

Dural carotid-cavernous sinus vascular malformation with facial nerve paresis.

Facial nerve paresis is rarely seen in dural cavernous sinus arteriovenous malformations or carotid-cavernous sinus fistulae. A patient with an otherwise typical presentation of a spontaneous carotid-cavernous sinus malformation was found to have ipsilateral infranuclear facial nerve paresis. Angiography revealed a dural arteriovenous malformation with early petrosal sinus filling. Possible mechanisms for the paresis include compression of the facial nerve by increased venous pressure and "stealing" of the arterial supply by the malformation.

Aged↗
PubMed1987

Recovery of vision after ischemic lesions: positron emission tomography.

We used [18F]fluoro-2-deoxyglucose positron emission tomography (PET) to study serial changes in the local cerebral metabolic rate of glucose in 5 patients with ischemic lesions of the posterior afferent visual system causing homonymous visual field defects. All 5 patients had striking impairment of glucose metabolism in the striate cortex shortly after ictus. In 2 patients, visual field defects abated, and repeat PET scans showed reduced size of the metabolic lesion and improvement of striate metabolism. Three patients did not recover vision, and repeat PET scans did not show improvement. Patients who recovered vision had ischemic lesions outside the occipital lobe, while those who did not experience improvement had primary damage to the occipital lobe itself.

Aged↗
PubMed1987

The syndrome of paradoxical worsening of dural-cavernous sinus arteriovenous malformations.

Three patients with dural arteriovenous malformations contiguous with the cavernous sinus had marked worsening of their neuro-ophthalmic symptoms. Such clinical deterioration has been attributed traditionally to increased blood flow through the malformations into the superior ophthalmic vein. However, arteriography in all three patients and magnetic resonance imaging (MR) in two patients demonstrated thrombosis of the entire superior ophthalmic vein. All patients subsequently underwent spontaneous, complete resolution of symptoms. This report describes a clinical syndrome of paradoxical worsening of cavernous sinus malformations and indicates that MR will aid in the management of these vascular malformations.

Aged↗
PubMed1987

Disseminated aspergillosis in a patient with ocular reticulum cell sarcoma.

A 75-year-old healthy woman developed uveitis and chorioretinal infiltrates OD compatible with reticulum cell sarcoma. She was admitted to hospital 18 months later with somnolence and confusion. Examination revealed diffuse white matter hypodensity on computed tomography and a persistent cerebrospinal fluid pleocytosis. At necropsy reticulum cell sarcoma was found in the right globe and Aspergillus fumigatus was present in almost every other organ, including the brain.

Aged↗
PubMed1987

Surface-coil MR of orbital pseudotumor.

Fifteen patients with clinical presentations compatible with idiopathic inflammatory orbital pseudotumor were examined by CT and MR imaging to determine if MR could add specificity to the CT appearance of this entity. MR was performed on a 1.5 T system, using surface-coil and head-coil techniques. Idiopathic pseudotumor was confirmed in nine patients on the basis of response to steroid therapy in the absence of local cause or systemic illness. One other patient had biopsy-proven idiopathic pseudotumor. Five patients proved to have other orbital entities, including metastases, infectious myositis, hemorrhage, and orbital sarcoid. In all 10 patients with confirmed pseudotumor, CT and MR were abnormal. MR abnormalities in 10 of 10 patients with pseudotumor were hypointense to fat and isointense to muscle on T1-weighted images. On T2-weighted images the lesions of pseudotumor were isointense or only minimally hyperintense to fat in nine of 10 cases; in one case, the enlarged muscle was markedly hyperintense to fat. The MR signal intensity of pseudotumor was similar to that found in infectious myositis and sarcoid. These findings contrasted to the MR appearance of the other disease entities examined. Metastases appeared markedly hyperintense to fat on T2-weighted images, while hematoma was hyperintense to muscle and isointense to fat on T1-weighted images and markedly hyperintense to fat on T2-weighted images. In our preliminary series, surface-coil MR appears to add specificity to the CT appearance of orbital pseudotumor.

Adolescent↗
PubMed1986

Remyelination follows antibody-induced central nervous system demyelination.

Remyelination after anti-galactocerebroside-induced demyelination in the guinea pig optic nerve was evident 17 days after the onset of demyelination. The tempo of remyelination was uniform for large- and small-diameter axons and progressed, with compaction and thickening of myelin sheaths. Demyelinated axons were found interspersed among remyelinated fibers and were consistently separated from oligodendrocytes by astrocytic processes. These findings indicate that central nervous system remyelination may occur after in vivo antibody-induced demyelination, but that new myelin formation may be limited by mechanical interference from astrocytic processes.

Animals↗
PubMed1986

Nerve fibre bundle visual field defects and intracranial mass lesions.

Nerve fibre bundle visual field defects are the hallmark of pathology at the optic nerve head or retina. In the present series, six eyes of four patients with large intracranial mass lesions demonstrated such field defects with visual acuity spared in three of the involved eyes. In no cases did visual function in the opposite eye offer a clue to the localization of the lesion.

Adult↗
PubMed1985

Lymphocyte subpopulations in Graves' ophthalmopathy.

We assessed the percentages of T-lymphocyte subsets, B lymphocytes, monocytes, and granulocytes in the mononuclear cell preparations of euthyroid patients with minimal and severe Graves' ophthalmopathy. Patients with active Werner class 4-5 and class 6 ophthalmopathy had statistically significant elevations of suppressor/cytotoxic T8+ lymphocytes. During successful corticosteroid therapy, the number of T8+ lymphocytes returned to the normal range. Mirroring these results, the T4/T8 ratio was initially depressed in patients with class 4-5 ophthalmopathy and increased during therapy. Our previous observations noted a decreased number of rosette-forming T lymphocytes in patients with severe ophthalmopathy. In this study, however, there were normal percentages of T3+ and T11+ lymphocytes, suggesting that the T lymphocytes are present in peripheral blood but they cannot form rosettes. There was a slight reduction of the percentage of the T11+ (erythrocyte receptor) lymphocytes in the patients with class 4-5 ophthalmopathy; however, it was not statistically significant. No significant differences were evident in any of the other T-lymphocyte subsets, B lymphocytes, monocytes, or granulocytes studied. We conclude that Graves' ophthalmopathy is characterized by a surface membrane defect associated with increased percentages of suppressor/cytotoxic T8+ lymphocytes. Successful corticosteroid therapy reverses these findings.

Adult↗
PubMed1985

Decreased visual acuity from optic disc drusen.

Although visual field defects occur commonly from optic disc drusen, reduction in visual acuity is rare. We describe four patients with reduced visual acuity and one with visual field constriction to the point of legal blindness that resulted from optic disc drusen. The acute episodic and stepwise nature of visual loss in some of the cases in our series suggests a vascular mechanism. Reduced visual acuity from drusen remains a diagnosis of exclusion. It should be considered, however, when visual loss has been acute and nonprogressive or stepwise in a nerve fiber bundle distribution and when visual acuity is not reduced until visual field constriction is severe.

Acute Disease↗
PubMed1985

Optic nerve involvement in the acute retinal necrosis syndrome.

Two patients with acute retinal necrosis syndrome demonstrated enlarged computed tomographic images of the optic nerves, a previously undescribed manifestation of this disorder to the best of our knowledge. One patient, with the bilateral variety of this syndrome, demonstrated bilateral optic nerve enlargement and, in one eye, appeared to achieve visual improvement following an optic nerve sheath decompression. The second patient, with the unilateral variety of the syndrome, demonstrated only unilateral optic nerve enlargement. These observations suggest that the intraorbital optic nerve may be primarily or secondarily involved in the acute retinal necrosis syndrome.

Acute Disease↗
PubMed1985

Hemifacial spasm treated with botulinum A toxin injection.

Fifteen patients with hemifacial spasm were treated with botulinum A toxin injections. All patients experienced relief from spasm, with the effect lasting an average of 12.2 weeks. Complications were tearing in four patients, inability to close the involved eye in three patients, corneal exposure in one patient, and ectropion in one patient. All complications were transient and deemed minor by the patients.

Adult↗
PubMed1985

Visual function in prolactinoma patients treated with bromocriptine.

Ten patients with prolactin-secreting pituitary adenomas (prolactinoma) and visual dysfunction were treated primarily with bromocriptine. Nine patients had improvement of visual field or acuity associated with computed tomography (CT) evidence of a decrease in tumor size and reduction of serum prolactin level (SPL). Visual improvement usually began within days of commencing bromocriptine therapy. One patient with initial improvement had a worsening of visual fields at 11 months despite a normal SPL and a stable CT appearance of tumor size. This patient and the single patient without visual improvement underwent trans-sphenoidal hypophysectomy (TSH), but neither patient had postoperative visual improvement. Two other patients underwent TSH for nonvisual reasons. The remaining six patients have maintained excellent visual function at last follow-up (average of 18 months on bromocriptine therapy). This study shows that bromocriptine is an effective short- and long-term therapy for most patients with visual dysfunction due to prolactinoma.

Adult↗