Biomedical subjects

A Srour

Publications and source records attributed to A Srour.

9 recordsLinked to original sources

PubMed2000

Prediction of malignant middle cerebral artery infarction by diffusion-weighted imaging.

BACKGROUND AND PURPOSE: This study was designed to analyze whether early diffusion-weighted imaging (DWI) provides reliable quantitative information for the prediction of stroke patients at risk of malignant brain infarct. METHODS: We selected 28 patients with a middle cerebral artery (MCA) infarct and proven MCA or carotid T occlusion on DWI and MRI angiography performed within 14 hours after onset (mean 6.5+/-3.5 hours, median 5.2 hours). Of these, 10 patients developed malignant MCA infarct, whereas 18 did not. For the 2 groups, we compared the National Institutes of Health Stroke Scale (NIHSS) score at admission, site of arterial occlusion, standardized visual analysis of DWI abnormalities, quantitative volume measurement of DWI abnormalities (volume(DWI)), and apparent diffusion coefficient values. Univariate and multivariate discriminant analysis was used to determine the most accurate predictors of malignant MCA infarct. RESULTS: Univariate analysis showed that an admission NIHSS score >20, total versus partial MCA infarct, and volume(DWI) >145 cm(3) were highly significant predictors of malignant infarct. The best predictor was volume(DWI) >145 cm(3), which achieved 100% sensitivity and 94% specificity. Prediction was further improved by bivariate models combining volume(DWI) and apparent diffusion coefficient measurements, which reached 100% sensitivity and specificity in this series of patients. CONCLUSIONS: Quantitative measurement of infarct volume on DWI is an accurate method for the prediction of malignant MCA infarct in patients with persistent arterial occlusion imaged within 14 hours of onset. This may be of importance for early management of severe stroke patients.

Adult↗

PubMed2000

Correspondence between functional magnetic resonance imaging somatotopy and individual brain anatomy of the central region: comparison with intraoperative stimulation in patients with brain tumors.

OBJECT: The goal of this study was to determine the somatotopical structure-function relationships of the primary motor cortex in individual patients by using functional magnetic resonance (fMR) imaging. This was done to assess whether there is a displacement of functional areas compared with anatomical landmarks in patients harboring brain tumors close to the central region, and to validate these findings with intraoperative cortical stimulation. METHODS: One hundred twenty hemispheres in 60 patients were studied by obtaining blood oxygen level-dependent fMR images in patients while they performed movements of the foot, hand, and face on both sides. There was a good correspondence between anatomical landmarks in the deep portion of the central sulcus on axial slices and the somatotopical organization of primary motor areas. Pixels activated during hand movements were centered on a small characteristic digitation; those activated during movements in the face and foot areas were located in the lower portion of the central sulcus (lateral to the hand area) and around the termination of the central sulcus, respectively. In diseased hemispheres, signal-intensity changes were still observed in the projection of the expected anatomical area. The fMR imaging data mapped intraoperative electrical stimulation in 92% of positive sites. CONCLUSIONS: There was a high correspondence between the somatotopical anatomy and function in the central sulcus, which was similar in normal and diseased hemispheres. The fMR imaging and electrical stimulation data were highly concordant. These findings may enable the neurosurgeon to locate primary motor areas more easily during surgery.

Adult↗

PubMed1997

Dosimetric and cytogenetic studies of multiple radiation-induced meningiomas for a single patient.

No criteria are currently available to determine the spontaneous or radiation-induced origin of a malignant tumor occurring in a previously irradiated area. This study presents the dosimetric and cytogenetic analysis of meningiomas diagnosed in irradiated brain areas from a single patient and a discussion of the karyotypes of spontaneous meningiomas and radiation-induced tumors published in the literature.

Adult↗

PubMed1997

[Program of Medical Information System and diseases of the respiratory tract (CMD, No.4). Study of 1,020 hospital stays out of the total of 18,253 hospitalizations at the Centre Hospitalier de Saint-Gaudens in the framework of the National Study of Costs].

OBJECTIVE: To analyse hospital activity, the characteristics and course of patients having been classified, by the programme of medical information system (French PMSI) in the major diagnostic category of respiratory disorders (CMD n(o) 4). STUDY: Using the files created by Saint-Gaudens Hospital (145 acute beds, 7000 annual admissions) for three years within the context of the national study of the cost of medical activity. A descriptive statistical analysis then an explanation of the variations of consumptions by stay and by patient. RESULTS: In CMD n(o) 4 there were 26 homogeneous groups of patients (GHM) representing 1020 hospital admissions (out of a total of 18,253) of whom 76 were admitted as an emergency, 63 were in the thoracic medicine group and 27 had a spell in intensive care, 73% were discharged home and 9.8% died. CMD n(o) 4 represented 9% of the hospitals synthetic activity index (ISA). Of these 822 patients had a mean age of 70, 60% of them had chronic disease and 20% were living alone. The variations of cost had been explained by GHM (P < 0.001), test of variants [ANOVA]) as well as by complementary indicators (performance status WHO) and a simplified index of severity. Men, elderly subjects and those with chronic disease consumed more. Hospital activity determined from CMD n(o) 4 has been compared to an extraction of stays based on pure diagnostic medicine (thoracic medicine) of the principal disorder: important differences were apparent, explained in large part by the method of admission, by the PMSI, respiratory tumours and ambulatory care. CONCLUSION: An analysis of activity in thoracic medicine has been able to give an over view of the hospital with the reserves linked to the system which were essentially economic and should be able to be compensated by later improvements seeking to give a more medical aspect to the description of hospital stays.

Adult↗

PubMed1996

Posttraumatic spinal subarachnoid cyst.

A case of posttraumatic compressive subarachnoid cyst of the thoracic spine studied by MR myelography, and myelo-CT is reported. This cyst was surgically confirmed and treated by shunting.

Adolescent↗

PubMed1994

Neurosurgical anatomy of the anterior interhemispheric approach for aneurysms of the anterior communicating artery (26.6.92).

The anterior interhemispheric approach for aneurysms of the anterior communicating artery was studied in ten cadavers. This approach presents several advantages over the pterional approach widely used in neurosurgery. It allows direct access to the region of the anterior communicating artery complex with minimal retraction of the brain and preservation of the olfactory tract and the gyrus rectus.

Cerebral Arteries↗

PubMed1994

[Changes in myocardial beta adrenergic receptors in left ventricular hypertrophy caused by barometric and volumetric overloads].

While most prior studies examined late stages of heart failure, we determined initial changes of beta-adrenergic receptors (beta-AR) during left ventricular chronic volume and pressure overload. We investigated right auricular (RA) and left ventricular (LV) beta-AR density (Bmax, fmoles/mg protein) and beta 1-AR percentage in two groups of patients undergoing valve replacement without LV systolic dysfunction (LV ejection fraction > or = 60%), with normal plasma catecholamine levels and echocardiography LV hypertrophy. These results were compared with the values of a control group, composed by 8 patients with mitral stenosis and 5 cardiac transplant donors, and the values of 5 patients undergoing heart transplantation because of end-stage idiopathic dilated cardiomyopathy. These results show that, before alteration of LV systolic function occurs, left ventricular chronic overload induces a selective down-regulation of LV beta 1-AR compensated by an increase in beta 2-AR. These variations may be due to LV hypertrophy induced by volume or pressure overload.

Catecholamines↗

PubMed1992

[Meningeal melanocytoma or multiple pigmented meningioma of the spinal canal. Report of a case. Review of the literature].

In a 64-year-old male with pain and weakness of the right lower limb, investigations disclosed a cervical tumor, several dorsal tumors, and tumoral infiltration of the lumbosacral area. Histological and, above all, immunohistochemical and ultrastructural features were suggestive of meningeal melanocytoma. Before the use of immunohistochemical and electron microscopy techniques, meningeal melanocytoma was designated by the term pigmented meningioma because its histological features bear some resemblance to those of meningioma. However, only a few cases of meningeal melanocytoma have been documented by immunohistochemistry and electron microscopy. Previously reported patients with meningeal melanocytoma had solitary tumors. In contrast, a review of the literature showed that multiple intraspinal or intraspinal and intracranial meningiomas are not exceptional, although meningiomatous infiltration is considerably less frequent. Treatment of such cases rests on surgery, radiotherapy, and chemoimmunotherapy.

Combined Modality Therapy↗

PubMed1984

Cerebral edema associated with meningiomas: possible role of a secretory-excretory phenomenon.

A retrospective study of cerebral edema in 40 patients with intracranial meningiomas seems to demonstrate that the extent of edema is not related to anatomical factors such as location. Histological type is more significant; cerebral edema is usually observed with meningothelial forms. Furthermore, the study of tumor cells by electron microscopic methods indicates that secretory-excretory activity is closely associated with with the production of peritumoral edema. The ultrastructural aspects of this secreted material are described, but further biochemical studies are necessary to determine its exact nature. The possible role of tumoral steroid receptors in the secretory-excretory phenomenon is discussed.

Brain Edema↗