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R B Morawetz

Publications and source records attributed to R B Morawetz.

At least 37 records · Page 2Linked to original sources
PubMed1986

Neurosarcoidosis causing ventricular loculation, hydrocephalus, and death.

Ten years after a diagnosis of sarcoidosis, a 33-year-old woman presented with a severe headache of 5 days' duration. Neuroradiologic evaluation revealed a large cystic lesion of the left temporal lobe, causing a mass effect. An exploratory operation proved the lesion to be a loculated portion of the temporal horn of the lateral ventricle. Drainage of the loculated ventricle relieved the patient's cephalgia. Within 2 months, however, pain in the head recurred and an unsteady, broad-based gait appeared. Reevaluation disclosed hydrocephalus for which a ventriculoperitoneal shunt was inserted. After this procedure, the patient did well neurologically for 1 year, after which seizures, personality changes, incontinence, and disturbance of gait developed. Death occurred after revision of the shunt, and widespread granulomatous disease was found at autopsy. Neurosarcoidosis, with emphasis on intracranial mass lesions in sarcoidosis, is discussed; the role of surgical treatment in some of these lesions, and in hydrocephalus, is stressed.

Adult↗
PubMed1986

Progressive multifocal leukoencephalopathy: three patients diagnosed by brain biopsy, with prolonged survival in two.

Since 1980, three immunocompromised patients have been proved to have progressive multifocal leukoencephalopathy (PML) by brain biopsy at the University of Alabama at Birmingham. Two patients presented with focal neurological findings, and the third presented with dementia. Computed tomography (CT) revealed white matter low density lesions in areas appropriate to the neurological abnormalities. Brain biopsy of areas that were abnormal on CT produced diagnostic tissue in all three patients. No patient suffered ill effects from the biopsy. Neuropathological findings on light microscopy were compatible with PML in each case, although there was diversity within the group. Involvement of gray and white matter was present in all biopsy specimens; oligodendrocytes, astrocytes, and neurons were affected. Electron microscopic demonstration of particles compatible with polyoma virus confirmed the diagnosis in each case. Immunosuppressive medication was discontinued in two of the patients; these two have survived more than 2 years after diagnosis. One of these two has gradually improved and is independent in simple activities of daily life. Brain stem and cerebellar involvement and seizure disorders have been present in all reported cases. PML can be accurately and rapidly diagnosed by brain biopsy, enabling therapeutic manipulations that may prolong survival.

Adult↗
PubMed1986

Brain biopsy for encephalitis.

Brain biopsy is justified in patients suspected of having encephalitis or viral encephalopathy because those patients are most likely to be helped if a diagnosis is made rapidly and with the greatest certainty possible. Neurosurgeons are occasionally reluctant to undertake brain biopsy because the procedure is diagnostic rather than therapeutic in intent. However, using currently available techniques a 1 cm3 sample of brain tissue can be taken with very low risk of morbidity or mortality. We recommend that the sample be taken from the anterior portion of the inferior temporal gyrus on the more affected side in patients with herpes simplex encephalitis, and from an area of maximum demonstrated involvement in other situations, using stereotactic techniques and intraoperative ultrasound as necessary. The risk to the operating surgeon and to the other members of the operating team appears very low in all of the situations discussed in this chapter. However, the authors feel that every patient should be approached as if he carries the hepatitis B virus. As indicated, the incidence of contracting hepatitis B after sustaining needle stick exposure to blood from persons positive for hepatitis B surface antigen is 10-15%. Conjunctival contamination by splash from the wound is a known method of inoculation of surgeons with hepatitis B virus and is a possible means for transmission of other viral diseases. We recommend that every patient be approached as if he has hepatitis B, not because the agent diseases discussed are known to be as infectious as hepatitis B, but because constant vigilance and careful technique offer the best protection to the surgeon and the members of the operating team in most situations, and because one can never be certain what agent diseases a given patient may harbor. With the exception of the Creutzfeldt-Jakob virus, the agents responsible for all of the viral diseases discussed are inactivated by standard procedures for sterilization of operating room instruments. Procedures necessary to inactivate the Creutzfeldt-Jakob disease virus have been presented. In the report documenting transmission of Creutzfeldt-Jakob disease through human growth hormone preparations the authors state, "We are once again dramatically reminded that human tissues are a source of infectious disease, and that any therapeutic transfer of tissue from one person to another carries an unavoidable risk of transferring the infection.(ABSTRACT TRUNCATED AT 400 WORDS)

Acquired Immunodeficiency Syndrome↗
PubMed1985

Brain abscess after esophageal dilation for caustic stricture: report of three cases.

Of 127 patients with intracranial suppuration (brain abscess and subdural empyema) treated from 1971 to 1984, 3 were children with brain abscesses who previously had developed esophageal stricture from the ingestion of caustic substances. Each child had undergone esophageal dilation on several occasions before the development of focal neurological findings. Surgical resection of the abscess resulted in good to excellent neurological recovery in all 3 patients. Two of the patients have been followed for long periods and have developed other severe illnesses, suggesting a defective immune status. Review of the English literature provides 8 other cases of this complication of esophageal stricture, with which the reported cases are compared.

Adolescent↗
PubMed1984

Factors and their influence on regional cerebral blood flow during nonpulsatile cardiopulmonary bypass.

In this study we examined the relationship of regional cerebral blood flow (CBF) to mean arterial pressure, systemic blood flow, partial pressure of arterial carbon dioxide (PaCO2), nasopharyngeal temperature, and hemoglobin during hypothermic nonpulsatile cardiopulmonary bypass (CPB). Regional CBF was determined by clearance of xenon 133 in 67 patients undergoing coronary bypass grafting procedures. There was a significant decrease in regional CBF (55% decrease) during CPB, with nasopharyngeal temperature and PaCO2 being the only two significant factors (p less than 0.05). In a subgroup of 10 patients, variation of pump flow between 1.0 and 2.0 L/min/m2 did not significantly affect regional CBF. We conclude that cerebral autoregulation is retained during hypothermic CPB. Under the usual conditions of CPB, variations in flow and pressure are not associated with important physiological or detrimental clinical affects.

Adult↗
PubMed1984

Indirect injury of the optic nerve.

Visual loss due to optic nerve injury after closed head trauma constitutes a formidable diagnostic and therapeutic challenge for the clinician. Assessment must be made of the site of optic nerve injury, and this is often difficult in the patient with an altered level of consciousness. A decision regarding optic nerve decompression must be formulated, yet the literature is confusing with regard to operative indications. In reviewing current pathogenetic theories, clinicopathological data, and therapeutic options, this report attempts to clarify the role of surgical intervention in indirect optic nerve injury.

Blindness↗
PubMed1984

Evolution and resolution of intracranial bacterial (mycotic) aneurysms.

Surgical therapy of bacterial intracranial aneurysms may prove difficult when multiple aneurysms are present or lesions are proximally located. Two patients underwent operation for bacterial intracranial aneurysms without resolution of their problems, in one case because of the involvement of a proximal branch of a dominant middle cerebral artery and in the other because of the presence of multiple bilateral aneurysms. Both patients underwent multiple angiographic evaluations during the course of treatment with documentation of complete resolution of their aneurysms over many months. The time course of the evolution and resolution of the bacterial intracranial aneurysms identified in the two patients is described, and antibiotic therapy and cardiac surgery are discussed.

Adolescent↗
PubMed1984

Correlation of cerebral blood flow and EEG during carotid occlusion for endarterectomy (without shunting) and neurologic outcome.

One hundred twenty-nine consecutive carotid endarterectomies performed for atherosclerotic ulcerative stenosis without the use of intraoperative shunting were analyzed prospectively in an effort to determine the significance of intraoperative ischemia. Intraoperative EEG and regional cerebral blood flow measurements were used to monitor these patients. Ten of the patients were excluded because of inadequate data, but none of these 10 patients experienced a complication. Factors analyzed included preoperative risk assessment according to the Mayo Clinic system of Sundt et al., intraoperative regional cerebral blood flow measurements, and intraoperative EEG changes. The overall mortality rate was 2.5%, the major morbidity rate was 2.5%, the minor morbidity rate was 1.7%, and the rate of transient neurologic dysfunction was 1.7%. The patients' preoperative state as determined according to the Mayo Clinic system of Sundt et al. was more useful in identifying patients at risk than was intraoperative EEG and regional cerebral blood flow monitoring.

Anesthesia, General↗
PubMed1983

Experience with brain biopsy for suspected herpes encephalitis: a review of forty consecutive cases.

From January 1973 through July 1981, 40 patients underwent brain biopsy for suspected herpes simplex encephalitis at the University of Alabama Medical Center. Biopsy was performed as a component of experimental antiviral studies to ensure correct diagnosis. A tentative diagnosis was made on clinical grounds, and the site of biopsy was chosen on the basis of localizing neurological signs, the electroencephalogram, and/or computed tomographic (CT) scan abnormalities. Patients ranged in age from 15 months to 73 years, with a median age of 19 years. Thirty patients were male, and 10 were female. Brain tissue from 17 of the 40 patients grew herpes simplex virus in tissue culture. There was one biopsy-related complication, a wound dehiscence requiring secondary closure. In no case was death attributable to the brain biopsy procedure. The outlook in patients with proven herpes encephalitis worsened directly with both an increasing interval between the onset of symptoms and the initiation of antiviral therapy and the age of the patient. The presence of a CT scan abnormality before the initiation of therapy was associated with a very poor prognosis. Three patients not included in this series were referred for brain biopsy to rule out herpes simplex encephalitis, but were found to have bacterial infections. Two had subdural empyemas and the third had a brain abscess with overlying subdural empyema. Current technique calls for biopsy of the anterior portion of the inferior temporal gyrus on the affected side.

Adolescent↗
PubMed1983

Pneumocephalus secondary to spontaneous bronchial-subarachnoid fistula.

We describe a patient in whom pneumocephalus appeared spontaneously, resulting from a communication between the bronchial tree and the thoracic subarachnoid space in association with squamous cell carcinoma of the lung. The communication was demonstrated by myelography and obliterated surgically. A review of the literature is included.

Bronchial Diseases↗
PubMed1982

Some clinical aspects of superficial temporal-middle cerebral artery bypass surgery.

Carotid occlusive disease may occur at the base of the skull and siphon without evidence of atheroma in the neck. Careful search for lesions in this location should be undertaken in any patients with TIAs or neurologic deficit when the extracranial carotid arteries appear normal. Unilateral frontotemporal headache may be an early symptom of stenosis in this location. Inaccessible lesions are often bilateral, although the symptoms may be unilateral. Superficial temporal-middle cerebral artery bypass on the symptomatic side affords relief of symptoms. Bypass on the contralateral side should be considered when and if symptoms subsequently develop related to the lesion on that side. The configuration of a carotid thrombus may enable one to determine that it is a retrograde rather than antegrade occlusion and hence is not amenable to endarterectomy, even in the acute situation. The use of a Fogarty catheter in such a setting would be ill-advised and potentially hazardous. Current experience suggests that risk of subsequent stroke is reduced after EC-IC bypass operation.

Adult↗
PubMed1981

Thresholds of focal cerebral ischemia in awake monkeys.

An awake-primate model has been developed which permits reversible middle cerebral artery (MCA) occlusion during physiological monitoring. This method eliminates the ischemia-modifying effects of anesthesia, and permits correlation of neurological function with cerebral blood flow (CBF) and neuropathology. The model was used to assess the brain's tolerance to focal cerebral ischemia. The MCA was occluded for 15 or 30 minutes, 2 to 3 hours, or permanently. Serial monitoring evaluated neurological function, local CBF (hydrogen clearance), and other physiological parameters (blood pressure, blood gases, and intracranial pressure). After 2 weeks, neuropathological evaluation identified infarcts and their relation to blood flow recording sites. Middle cerebral artery occlusion usually caused substantial decreases in local CBF. Variable reduction in flow correlated directly with the variable severity of deficit. Release of occlusion at up to 3 hours led to clinical improvement. Pathological examination showed microscopic foci of infarction after 15 to 30 minutes of ischemia, moderate to large infarcts after 2 to 3 hours of ischemia, and in most cases large infarcts after permanent MCA occlusion. Local CBF appeared to define thresholds for paralysis and infarction. When local flow dropped below about 23 cc/100 gm/min, reversible paralysis occurred. When local flow fell below 10 to 12 cc/100 gm/min for 2 to 3 hours or below 17 to 18 cc/100 gm/min during permanent occlusion, irreversible local damage was observed. These studies imply that some cases of acute hemiplegia, with blood flow in the paralysis range, might be improved by surgical revascularization. Studies of local CBF might help identify suitable cases for emergency revascularization.

Anesthesia↗
PubMed1979

Regional cerebral blood flow thresholds during cerebral ischemia.

The development of methods of determining regional cerebral blood flow (rCBF) has made possible the determination of thresholds for the appearance of cerebral ischemia. These thresholds vary depending on the method used for assessing cerebral ischemia. The following thresholds have been determined in man and nonhuman primates: 20 cc/100 g per min, electroencephalogram (EEG) and evoked cortical potential abnormalities appear, paralysis seen in waking monkeys; 15 cc/100 g per min. EEG and evoked cortical potential are lost; 12 cc/100 g per min, flows at this level in excess of 120 min produce infarction in waking animals; and 6 cc/100 g per min, massive loss of intracellular [K+]. The residual rCBF and the duration of ischemia determine the appearance of infarction in waking Macaca irus monkeys.

Animals↗