Biomedical subjects
Publications and source records attributed to N de Tribolet.
A rare neurinoma of the labyrinthine portion of the facial nerve with a parietal meningioma is reported. The association of these two tumors is discussed. Steroid receptor assays were performed. No hormone receptors were found, and the levels of estradiol, progesterone, and testosterone in the plasma were normal.
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A case of choroid plexus papilloma of the cerebellopontine angle that was revealed by a subarachnoid hemorrhage in a 5-year-old boy is presented. Subarachnoid hemorrhage and choroid plexus papilloma in children are discussed.
This is a review of 80 cases of intracranial meningiomas, which were operated on in the neurosurgical Service of Lausanne. 51 tumors were associated with an area of low attenuation of variable extension on the CT-scan. In 49 of these, the low attenuation areas corresponded to oedema. In two of them a cyst was discovered at operation. One was a subarachnoid cyst and the other one was an intracerebral cyst separated from the tumor by a thin layer of cerebral cortex. A correlation was attempted between these areas of low attenuation and the clinical history, the CT-scan characteristics, the location, the macroscopic appearance at operation and the histology of the tumors. From these data, the typical features of a meningioma more likely to be associated with an area of low attenuation on the CT-scan were determined. This tumor is often located in the subfrontal area or in the middle base of the skull, and epilepsy or increased intracranial pressure are more likely to be present. The most common histological type is syncytial.
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Studies were designed to investigate whether the cellular immunodeficiency state observed in human glioblastoma patients could be due to inhibitory factors released by the tumor cells. Cultured human glioblastoma cells were found to secrete an interleukin 1-like factor (m.w. 22,000) and a factor (m.w. 97,000) that inhibits interleukin 2 (IL 2)-dependent T cell mechanisms. This is demonstrated by its inhibitory effect on the IL 2-induced proliferation of T cell clones and on the induction of alloreactive cytotoxic T cells in mixed lymphocyte cultures. Additionally the glioblastoma cell-derived 97,000-m.w. factor inhibited growth of neuroblasts but not of fibroblasts and thus shares the characteristics of the neuroblast growth inhibition factor (NGIF) previously detected in the supernatant of fetal rat glia cell cultures. If released by glioblastoma cells in vivo, the factor may contribute to impaired immunosurveillance and to the cellular immunodeficiency state detected in the patients.
A case is presented of cervical myelopathy with acute posttraumatic onset, due to ossification of the posterior longitudinal ligament. This disease is rare outside Japan. The progressive ossification appears to be secondary to multiple ankylosing degenerative discopathies.
The authors report on the successful cefotaxime treatment (one of the newer cephalosporins) of K. pneumoniae meningitis which developed while the patient was under treatment with an older cefalosporin, cephalothin.
The case of an adult patient with a small frontoparietal convexity meningioma surrounded by a huge cyst is reported. The cyst fluid had a very high protein content, but there was no distinct cyst wall. Knowledge of the radiological features of this rare condition may prevent confusion with a malignant tumour.
A stem cell assay for human malignant gliomas has been developed. Cells obtained from tumor biopsies grew into colonies composed of malignant glial cells, as documented by histochemical, immunohistochemical, and immunobiological techniques. Studies suggest that the disaggregated cells are representative of the cells within the solid tumor. Clonogenic cells were obtained from 48 tumors and analyzed for their in vitro sensitivity to graded doses of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). The in vitro anti-tumor activity of BCNU at clinically achievable doses was compared to clinical response to the agent based on changes in computerized tomographic scan, radionuclide brain scan, and neurological examinations. Twenty-two patients received nitrosoureas before or after tumor specimen analysis, and were eligible for in vitro-in situ correlations. Clinical tumor sensitivity to nitrosoureas was predicted by culture results in 42% of all evaluable patients, and clinical resistance was predicted in 100%. The capability of the assay can be appreciated best for the 13 patients not treated with BCNU prior to culture; the in vitro prediction of clinical sensitivity and resistance was 71% and 100%, respectively. Preliminary findings show that clinical tumor resistance to BCNU may result from "intrinsic" cell resistance in some patients and from inadequate delivery of drug to tumor cells in other cases. The potential utility of this method to study the reason(s) for tumor cell resistance to drugs, to screen new chemotherapeutic agents, to individualize patient treatment, and to investigate tumor biology is discussed.
The authors report 8 patients who developed an epidural hematoma after having been submitted to 1 or 2 computed tomographies (CT) which did not yet show the hematoma. The initial CT was done 1 to 6 hours after the accident. The delayed hematoma was diagnosed 3 and a half hours to 7 days after the accident. Secondary clinical deterioration occurred in 6 patients and was dramatic in 4 of them. Delayed epidural hematoma seems to be a frequent event; our 8 cases represent 10 % of all epidural hematomas operated during the period under consideration. This has to be taken into account when taking care of head injured patients after negative CT. The authors propose a list of indications for repeating CT. The current views on mechanisms of formation of epidural hematomas are discussed in the light of the increasing number of reported cases of delayed epidural hematoma.
Post-traumatic subdural hygromas, or hydromas, are collections of fluid most often caused by severe head injuries. They present from the onset as hypodense pictures on computerized axial tomography scan (CAT-scan). CAT-scan is the best way to diagnose and to follow the evolution of hygromas. Out of 3002 patients admitted for head injuries, the authors have collected 70 cases of hygromas. 24 of these 70 patients underwent burrhole evacuation of the hygroma. The other 46 had conservative treatment. In both groups, the clinical picture, at short or long-term follow up, was more influenced by the associated brain injuries (extra- or subdural hematomas, cerebral contusion) than by the evolution of the hygroma itself. The surgical treatment of the hygroma was seldom followed by a significant improvement in the patients' condition. As the size of hygromas usually diminishes spontaneously, it seems appropriate most of the time to treat them conservatively and to follow them by CAT-scan, according to the clinical picture.
Myelin basic protein (BP) is a specific constituent of the myelin sheath. This structural protein cannot be detected in the cerebrospinal fluid (CSF) unless myelin is acutely degraded. In order to detect active demyelinating diseases, BP was measured in CSF samples of radioimmunoassay. The assay is specific and sensitive to as little as 1.5 to 2.5 ng/ml BP. A moderate non-parallelism between the standard curve and various dilutions of CSF samples indicates that in CSF BP is present in an altered state. Over 1000 CSF samples have been measured in a double-blind study, in which 100 patients were selected and their clinical records evaluated. Twenty-eight patients without demyelinating disease had BP levels lower than 2.5 ng/ml. 72 patients had values higher than 2.5 ng/ml. Among them, the most frequent causes of demyelination were multiple sclerosis (19 cases), brain tumors (22 cases) and cerebral or spinal vascular accidents (12 cases). During a single acute demyelinating episode, BP levels revert to background levels within a few days. In contrast to immunological anomalies observed in the CSF, the presence of BP is concomitant with the breakdown of myelin. The size and location of the lesion influence the level of BP in the CSF. Thus, the assay is useful for the detection of active demyelination in the central nervous system and in following the course of the disease, although normal values do not rule out the presence of demyelinating lesions. For the time being, therefore, this assay should be restricted to specialized neurological centers and selected patients.
Apnea is an essential criterion for the diagnosis of brain death and is often difficult to determine in artificially ventilated patients. Absolute apnea is the absence of respiration when the respiratory center is maximally stimulated by hypercapnia. In a study of 13 cases we show that measuring PaCO2, which must be equal or superior to 50 mm Hg, is mandatory in confirming the stimulation of the respiratory center. The duration of apnea necessary to reach this level is highly variable. It does not induce hypoxemia when the technique of apneic oxygenation is used.
The reactivity spectrum of five different monoclonal anti-melanoma antibodies cross-reacting with gliomas and neuroblastomas and one monoclonal anti-glioma antibody cross-reacting with melanomas and neuroblastomas was investigated. Comparison of the binding activity of these monoclonal antibodies for 11 melanoma, seven glioma, and three neuroblastoma cell lines showed that each of these clones had a different pattern of cross-reactivity. The results indicated that the antigenic determinants detected by these antibodies were not associated with the same antigen and thus suggested the existence of at least six different antigens common to melanomas, gliomas, and neuroblastomas. Since all these tumors are known to derive from cells originating embryologically from the neural crest, it can be assumed that the antigens recognized by our monoclonal antibodies are neuroectodermal differentiation antigens. However, absorption with fetal brain homogenates abolished only the binding of monoclonal anti-glioma antibody, but did not modify the binding of monoclonal anti-melanoma antibodies.
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6 cases of so-called redundant nerve roots of the cauda equina are reported, which brings the total number of cases described in literature to 27. The differential diagnosis of the myelographic picture of tortuous filling defects is discussed. The authors believe that the majority of these cases is caused by chronic compression of the nerve roots.