Biomedical subjects

W G Ellis

Publications and source records attributed to W G Ellis.

At least 55 records · Page 3Linked to original sources

PubMed1986

Brain gliomas: sonographic characterization.

To determine the ability of ultrasound (US) to help characterize brain lesions and determine the best site for biopsy, intraoperative sonographic examination of nine intracerebral gliomas was performed and correlated with the preoperative computed tomographic (CT), gross intraoperative, and histopathologic findings. Real-time US provided a precise and rapid method for intraoperative localization of intracerebral neoplasms in all cases. While the sonographic appearance of gliomas is nonspecific, US added information on tumor characterization to that provided by CT. All gliomas were sonographically echogenic compared with surrounding brain. US permitted good characterization of the cystic components of tumors; portions of the operation therefore involved surgical drainage rather than resection. Autopsy specimens from five anaplastic cerebral gliomas were examined with US and found to be echogenic. The central portions of all five tumors were echogenic and corresponded to areas of tumor necrosis; thus they were poor sites for biopsy. Alternatively, the best site for biopsy was the inner portion of the echogenic margin of the mass, which usually represented areas of active tumor growth. The information obtained from both preoperative CT and intraoperative US is beneficial in characterizing lesions and predicting the best site for biopsy.

Astrocytoma↗

PubMed1986

Changes in the auditory brainstem response associated with intravenous infusion of unconjugated bilirubin into infant rhesus monkeys.

The auditory brainstem response (ABR) was monitored in nine infant rhesus monkeys during the intravenous infusion of 50-168 mg/kg of unconjugated bilirubin. Sulfisoxazole (200 mg/kg) was sometimes given near the end of or just before the bilirubin infusion if no obvious ABR change had yet occurred. Five of the animals were term gestation, four were preterm, and they ranged from 1 to 40 days of age at the time of study. The three oldest term animals, studied at 20, 35 and 40 days of age, respectively, showed variable changes in the ABR waves during bilirubin infusion and these changes were not altered further by sulfisoxazole administration. The other two term infants, studied at 1 and 6 days of age, respectively, showed sulfisoxazole enhanced ABR wave latency increase and amplitude reduction followed by loss of the ABR. Both of these animals became apneic following ABR loss and eventually died. The ABR reappeared in one animal prior to death. Minimal gross and microscopic changes were present in the brain of the 6-day-old animal at autopsy. The four preterm animals all had a progressive wave amplitude decrease followed by loss of the ABR with bilirubin alone. These preterm animals were sacrificed shortly after the ABR loss with only one showing yellow staining of the basal ganglia at autopsy. The infant rhesus monkey may be a useful paradigm for bilirubin-induced ototoxicity as manifested by potentially reversible ABR changes. The changes are dependent on gestational and chronological age of the animal and appear to occur in the peripheral eighth nerve or cochlea as well as in brainstem pathways.

Animals↗

PubMed1985

Subacute diencephalic necrosis and dural arteriovenous malformation.

We report a case of congestive venous necrosis involving the diencephalon symmetrically, presumably precipitated by a dural arteriovenous malformation (AVM). The patient presented with a 1-month history of intermittent confusion and gait ataxia. The initial radiological work-up revealed a dural AVM. The patient's subsequent deterioration was accompanied by computed tomographic findings of diencephalic congestion. Pathological examination showed subacute necrosis of the diencephalon. We discuss the pathogenesis of this case of subacute diencephalic necorsis and its possible relationship to the entity of subacute diencephalic angioencephalopathy.

Brain Diseases↗

PubMed1984

Central nervous system coccidioidomycosis: a clinicopathologic study of treatment with and without amphotericin B.

The clinical and pathologic findings in 32 patients with central nervous system (CNS) coccidioidomycosis were studied. Seventeen patients had received more than 1.5 g of amphotericin B (AMB), chiefly intravenously, during treatment periods of up to eight years. Eight patients had received 246 mg to 1.3 g of AMB, and three patients had received only brief treatment (one to three days; total dose, no more than 100 mg). Fifteen patients had not received AMB. Significant clinical differences between the patients treated with and without AMB were longer survival time following diagnosis of illness (P less than 0.05) and more frequent cranial nerve signs in the treated patients (P = 0.089). The wide spectrum of macroscopic and microscopic lesions in the CNS included meningitis, ventriculitis, hydrocephalus, and cerebritis. Long-standing infections were associated with disseminated discrete foci of gliosis and infarcts in the brain, particularly in the basal ganglia and deep white matter, related to endarteritis obliterans in basilar meninges. In contrast to patients with CNS and systemic mycoses treated with amphotericin B methyl ester (J Infect Dis 146:125, 1982), no diffuse lesions of white matter were found in patients treated with or without AMB. Histopathologic patterns observed in this study included leptomeningitis alone, leptomeningitis with cerebritis, leptomeningitis with cerebritis and infarcts, and the unusual pattern of disseminated miliary granulomas. The frequency and extent of CNS lesions in the groups treated with and without AMB were not significantly different. It is concluded that AMB therapy, while prolonging survival, does not alter the spectrum of pathologic findings in CNS coccidioidomycosis infection.

Adolescent↗

PubMed1983

Herpes simplex virus infection of motor neurons: hypoglossal model.

Herpes simplex virus type 1 (HSV) was inoculated into the tongue muscle of A/J mice. Typical HSV vesicles developed on the tongue surface 4 days after HSV inoculation. Virus was isolated from hypoglossal nerve explants, and inflammatory cells appeared where the hypoglossal nerve exists from the ventral medulla. HSV viral capsids were present in astroglial cells near the point of nerve exit. A focal encephalitis ensued with immunoperoxidase staining of HSV antigens in neurons of the hypoglossal nucleus. These findings indicate that HSV can penetrate the neuromuscular junction, travel in a pure motor nerve, and produce a focal encephalitis in the corresponding central nervous system motor nucleus.

Animals↗

PubMed1983

The fetal hippocampus. A possible pitfall and a useful anatomical landmark in evaluation of the biparietal diameter.

A well-demarcated hypoechoic region was seen just lateral to the collicular plate during measurement of the fetal biparietal diameter (BPD) in 101 (70%) of 144 ultrasound examinations and confirmed on postmortem sonographic water-bath studies of fetal brains. This structure was found to represent the hippocampus, with its lateral border formed by the trigone of the lateral ventricle. It should not be confused with an abnormal entity such as a ventricular cyst. Recognition of this hypoechoic region in conjunction with previously described structures is a useful method of obtaining consistent BPD measurements.

Cephalometry↗

PubMed1982

Leukoencephalopathy in patients treated with amphotericin B methyl ester.

Clinical and autopsy studies of 14 patients treated with amphotericin B methyl ester (AME) for focal, disseminated, and nervous system mycotic infections revealed a high incidence of progressive neurologic dysfunction (dementia, akinesia, mutism, hyperreflexia, and tremor) and diffuse white matter degeneration. All of seven patients who received greater than 9.8 g of AME intravenously developed severe neurologic and neuropathologic changes. Two of three patients given 5-7.2 g of AME developed less severe neurologic symptoms; all three had mild diffuse white matter gliosis. Four patients given less than 1.5 g of AME had no bran abnormalities except those related to coccidioidal meningitis. Thirty-one control patients who died on untreated or amphotericin B-treated coccidioidal meningitis showed no diffuse white matter abnormalities. These findings indicate that prolonged administration of AME and/or other contaminating polyenes injures human white matter. Long-term animal studies, with particular attention to nervous system histology, must precede human use of other polyene derivatives.

Adolescent↗

PubMed1981

Pineoblastoma with ganglionic and glial differentiation: report of two cases.

Two cases of pineoblastoma in infants are reported. Both cases exhibited ganglionic and astrocytic differentiation, and one case also showed retinoblastomatous features. Divergent differentiation has been frequently reported in pineocytomas, but ganglionic and glial features in the highly malignant primitive pineoblastoma are unusual. These cases extend the concept of pineoblastoma and further confirm the differentiating potential of primary pineal parenchymal neoplasms.

Brain Neoplasms↗

PubMed1980

Persistent isodense intraventricular hematoma caused by intraventricular saccular aneurysm.

A case of intraventricular hemorrhage secondary to an intraventricular saccular aneurysm is presented in which the hematoma mass gave a false appearance of resolution secondary to its progressive isodense appearance on serial computerized cranial tomograms. Intraventricular saccular aneurysms are unusual lesions and a most uncommon cause of intraventricular hemorrhage. Diagnosis of intraventricular hemorrhage has been greatly facilitated since the advent of cranial computerized tomography though elucidation of the definitive cause of hemorrhage in this case still depended upon cerebral angiography. In addition, the development of isodensity by the hematoma mass on serial computed tomograms has led to this case report.

Adult↗

PubMed1979

Virus-simulating structures in the optic nerve head in Creutzfeldt-Jakob disease.

A 68-year-old man was treated for and died of Creutzfeldt-Jakob disease. At autopsy we found multiple virus-like particles in the optic nerve head, but saw no similar structures in the cornea. Although these particles were morphologically similar to those previously reported in brain, we believe that they are not virions but unrelated cellular structures. We speculate that the causative agents may be naked membrane bound nucleic acids rather than true viruses. We found no optic atrophy or other specific pathologic changes in the eyes; severe occipital cortical degeneration was responsible for the patient's visual loss.

Aged↗

PubMed1977

Focal eosinophilic granuloma of the temporal lobe. Case report.

The authors describe the clinical, pathological, and therapeutic aspects of a case of focal temporal lobe eosinophilic granuloma, presenting with otitis media and meningitis, and evolving subsequently into a temporal lobe mass. This triad, otitis media, meningitis, focal cerebral lesion with systemic manifestations of inflammation, eosinophilia of blood and cerebrospinal fluid, should suggest eosinophilic granuloma in the differential diagnosis. The lesion is sensitive to relatively small doses of radiation.

Brain Diseases↗

PubMed1975

Gemistocytic astrocytes in gliomas. An autoradiographic study.

Tritiated thymidine (3-H-T) was administered intravenously to seven patients with cerebral gliomas. Autoradiographs of biopsy specimens excised within the next four hours and of autopsy specimens from three of these patients obtained three weeks to six months after the single pulse of 3-H-T revealed the following: (a) no gemistocytic astrocytes and only a few giant astrocytes were labeled in biopsy specimens, despite a high overall labeling index of 5-10% (percentage of cells labeled in the total cell population); and (b) scattered foci of labeled genistocytes occurred in autopsy specimens, despite a sharp drop in overall labeling index. In histologic sections of these same specimens, genistocytes and giant cells occurred as the major cell types in an irradiated tumor, in large clusters near foci of degeneration, and as isolated cells in anaplastic foci. These findings suggest that: 1) gemistocytes and giant astrocytes are similar in origin and growth potential regardless of minor variations in morphology; 2) these cells multiply slowly, if at all, and are closely related to regressive changes within the tumor; 3) these cells may reflect profound proliferative activity in adjacent neoplastic cells; and 4) the labeling index and malignant potential of the tumor as a whole depend upon the more rapidly dividing tumor elements. Thus, if genistocytes and giant cells indicate malignancy, they do so secondarily, and the biologically harmless gemistocyte may be the loser in an intense competition for the substrates needed in cell proliferation.

Adolescent↗

PubMed1974