PubMed Health⌕ Search

Biomedical subjects

M Mikhael

Publications and source records attributed to M Mikhael.

13 recordsLinked to original sources
PubMed1995

Operative confirmation of three-dimensional computed tomographic and magnetic resonance imaging of cerebrovascular pathology.

The conventional neuroradiological evaluation of aneurysms and arteriovenous malformations employs computed tomography (CT), magnetic resonance imaging (MRI), and detailed cerebral angiography. These techniques may be inadequate to define fully the cerebrovascular anatomy in patients with giant aneurysms or with arteriovenous malformations (AVMs) located near so-called eloquent brain structures. Therefore, we examined the usefulness of three-dimensional (3-D) MRI and CT images of the brain and cerebral vessels for predicting operative anatomical findings in selected cases of complex cerebrovascular pathology. In six of nine (67%) patients with giant aneurysms undergoing direct surgical treatment, the 3-D images were confirmed to be accurate, and they furnished information that is not available by conventional imaging. In three of these nine (33%) patients, failure of the 3-D images to predict operative findings accurately could be directly related to inappropriate imaging technique or to anatomical findings below the limit of resolution for CT or MRI. In 13 of 19 (68%) patients with an AVM, the 3-D images were considered helpful for treatment selection or planning, primarily because they enhanced the understanding of the relationship of the AVM nidus to brain structures of known functional significance. The results of our initial experience with 3-D imaging of cerebrovascular pathology are described in this report.

Adolescent↗
PubMed1987

Supratentorial gliomas: surgical considerations and immediate postoperative results. Gross total resection versus partial resection.

Forty-two patients with supratentorial gliomas not involving the basal ganglia (extraganglionic) were studied pre- and postoperatively with computed tomographic (CT) scans to evaluate the effect of the extent of surgical resection on the immediate postoperative results. Thirty-three patients (79%) had malignant astrocytic gliomas (glioblastoma or anaplastic astrocytoma), 4 patients (10%) had well-differentiated astrocytomas, and 5 (12%) had oligodendrogliomas. The median age was 58 years, and the median Karnofsky rating was 70. There was no operative mortality. Six patients (14%) had surgical complications. A gross total resection was defined as the absence of any abnormal enhancement on the postoperative CT scan. A nearly gross total resection had been accomplished when less than 10% of the preoperatively enhancing mass was still seen. A partial resection was indicated by the presence of more than 10% of the enhancing lesion on the postoperative CT scan. A gross total or nearly gross total resection was accomplished in 36 patients (86%), and an improved or stable postoperative neurological status was present in 35 of these patients (97%). In contrast, the rate of neurological morbidity after a partial resection was 40%. Supratentorial extraganglionic gliomas, regardless of their histological type, generally were well-circumscribed lesions except at the level of the ventricular wall, where glioblastomas and anaplastic astrocytomas blended with the subependymal white matter from which they seemed to arise.

Astrocytoma↗
PubMed1987

Effect of the extent of surgical resection on survival and quality of life in patients with supratentorial glioblastomas and anaplastic astrocytomas.

Thirty-one patients operated upon for supratentorial glioblastomas or anaplastic astrocytomas were studied to evaluate the effect of the extent of surgical resection on the length and quality of survival. The median age was 50 years and the median preoperative Karnofsky rate was 80. Twenty-one patients (68%) had glioblastoma multiforme, and 10 patients (32%) had anaplastic astrocytoma. Early postoperative enhanced computed tomography was used to determine the extent of tumor resection. Gross total tumor resection was accomplished in 19 patients (61%), and subtotal resection was performed in 12 patients (39%). The two groups were comparable regarding age, sex, pathological condition, preoperative Karnofsky rating, tumor location, postoperative radiation therapy, and postoperative chemotherapy (P greater than 0.05). The gross total resection group lived longer than the subtotal resection group by life table analysis (P less than 0.001; median survival of 90 and 43 weeks, respectively). Postoperatively, the mean functional ability measured by the Karnofsky rating was significantly increased in the gross total resection group (P = 0.006), but not in the subtotal resection group (P greater than 0.05). The difference in degree of change between preoperative and postoperative Karnofsky rating in the two groups was statistically significant (P = 0.002). The gross total resection group spent significantly more time after the operation in an independent status (Karnofsky rating greater than or equal to 80) compared to the subtotal resection group (P = 0.007; median time of 185 and 12.5 weeks, respectively). Gross total resection of supratentorial glioblastomas and anaplastic astrocytomas is feasible and is directly associated with longer and better survival when compared to subtotal resection.

Adult↗
PubMed1983

Transsphenoidal microsurgery of pituitary macroadenomas with long-term follow-up results.

The authors have reported on 108 patients with pituitary macroadenomas (measuring 2 cm in at least one diameter) who underwent 117 transsphenoidal operations and five craniotomies, and were followed for periods ranging from 6 months to 14 years. Vision improved in 90% of the patients. Gross total tumor removal with no evidence of residual tumor tissue demonstrable on the postoperative computerized tomography scan was accomplished in 41% of cases. However, gross total tumor removal is not synonymous with complete tumor removal. Endocrine cure was possible in 25% of prolactin-secreting and 20% of growth hormone-secreting adenomas. The incidence of recurrence was 12%, with the majority occurring from 4 to 8 years postoperatively. Both the tumors with suprasellar extension of more than 2 cm and the hard fibrotic tumors had a higher recurrence rate. Postoperative administration of radiation therapy has been associated with a significantly lower recurrence rate than when this therapy was withheld. Transsphenoidal surgery of pituitary macroadenomas confined to the extra-arachnoid space is associated with a relatively small number of complications. The operative technique used in this series is described.

Adenoma↗
PubMed1979

A comparison of alcoholics and heroin abusers: computerized transaxial tomography and neuropsychological functioning.

A number of conclusions may be drawn from the present neuropsychological and neuroanatomical assessment of alcoholic and heroin abusers: (1) Heroin abusers display deficits on the Category Test, TPT (Time and Localization) and Raven's Progressive Matrices (Set I and II) when compared to controls. (2) Alcoholics show significantly greater deficits than heroin abusers on these tests. (3) Duration of heroin and alcohol abuse are positively related to the extent of the observed deficits. (4) Observed deficits on the Progressive Matrices and Category tests appear to be reversible in the heroin abuser, but not the alcoholic, after comparable periods of remission. (5) The same proportion (1/15) of alcoholics and heroin abusers showed evidence of cerebral atrophy based on enlarged ventricular size.

Adult↗
PubMed1976

Optimal utilization of computerized cranial tomography and radionuclide brain imaging.

The results of computerized cranial tomography and radionuclide brain imaging in 490 patients were compared in relationship to the patients' clinical presentation. In 195 patients with focal neurologic abnormalities, both tests detected most lesions, but computerized cranial tomography was slightly more accurate overall. Results of both studies were normal in 69 percent of 295 patients with nonfocal neurologic presentations, and radionuclide imaging failed to detect lesions in only five patients with nonfocal presentations. These results suggest that radionuclide imaging can be used to accurately screen most patients with nonfocal neurologic presentations. An exception is the patient presenting with dementia, in whom computerized cranial tomography provides details of the anatomy of the ventricular cavities and cerebral cortex. This study demonstrates a continuing role of importance for radionuclide imaging in the evaluation of patients with neurologic disease and provides data to allow a rational approach to the optimum use of both techniques.

Atrophy↗
PubMed1976

Value of routine cerebral radionuclide angiography in pediatric brain imaging.

In addition to static brain images, cerebral radionuclide angiograms (CRAGs) were performed in 1,051 children to determine the value of routine radionuclide angiography. The CRAG resulted in a statistically significant increase in detection of abnormalities (p less than 0.01), as it provided the only evidence of confirmed abnormalities in 60 children (5.7%). The CRAG helped detect subdural fluid collections, cerebrovascular disease, and cerebral cysts, but it was of little value in detecting hydrocephalus. For maximum diagnostic yield, a CRAG should be performed with all pediatric brain-imaging studies.

Brain Diseases↗