PubMed Health⌕ Search

Biomedical subjects

J Tamraz

Publications and source records attributed to J Tamraz.

At least 19 recordsLinked to original sources
PubMed1994

Neuroradiologic investigation of the visual system using magnetic resonance imaging.

The aim of this review is to give highlights about technical imaging aspects with which researchers in the neuro-ophthalmologic fields ought to be familiar. After a short overview of history of anatomy of the visual system, a review of the main anatomic details and their corresponding MRI aspects concerning the visual pathways is proposed. Reference lines suitable for MR imaging of the visual system in normal and in diseased states are proposed to orient the neuroradio-ophthalmologic investigations. Brain, cutaneous, and bony landmarks are given to help multimodality imaging approaches, indispensable for anatomofunctional correlations. The neuro-ocular plane is used as the reference for the screening of the visual pathway in its entirety and retained as the orientation of choice for studying orbital optic nerves and eyes. Two other reference lines primarily devoted to temporal lobe imaging, are proposed for the study of the intracranial optic path: the chiasmatocommissural line and the commissural-obex, brainstem axis reference line. Based on brain commissural landmarks present in all vertebrates, these two lines are also helpful in comparative brain anatomic and physiologic studies in vivo as well as in vitro.

Algorithms↗
PubMed1993

[Brain morphometry using MRI in Cri-du-Chat Syndrome. Report of seven cases with review of the literature].

The authors present the results of a morphometric study of the brain of 7 patients with cat cry syndrome, explored with Magnetic Resonance Imaging (MRI). A method is proposed in order to facilitate the identification of the anatomical slices. A characteristic anomaly is observed as a marked atrophy of the brainstem predominating at the pontine level and associated with a small cerebellum, atrophic middle cerebellar peduncles and cerebellar white matter. This apparently systematized atrophy obvious in children, seems similar to the one observed in patients presenting a olivopontocerebellar atrophy, possibly correlating with disturbance of coordination and developmental delay in motility as observed in these patients. This does not implicate the same subjacent functional neuroanatomical pathways.

Adolescent↗
PubMed1990

[Eye movements: initial dynamic approach in high resolution magnetic resonance imaging].

New MR softwares allow a dynamic display of different fonctionnal anatomical regions. This work is a first attempt to visualize the ocular movements. A video tape constitute the support of our results. Technically, the work is performed on a Signa 1,5 T GE CGR System. During each MR acquisition, the subject is asked to fix his gaze successively on each spot of a scale set inside the bore of the magnet. Twenty four images are performed to show the entire lateral course of the globes. The examination time is about half an hour. The video display show the movements of agonist and antagonist muscles, the eyeballs and the optic nerves displacements, in the axial neuro-ocular plane (NOP). Different clinical applications of this new method are discussed (muscular surgery...).

Eye Movements↗
PubMed1988

Fetal curarization for prenatal magnetic resonance imaging.

Fetal magnetic resonance (MR) imaging was performed at 33 weeks of gestation for investigation of a posterior fossa abnormality found at ultrasound screening. Fetal movements were abolished by vecuronium injected under ultrasound guidance into the umbilical vein. MR images showed atrophy of the left cerebellar lobe with cisternal dilatation. These were confirmed postnatally by CT scan.

Adult↗
PubMed1988

[Cerebral MRI in the study of prognostic factors in AIDS. Hypotheses from tests on 15 patients].

In an attempt to determine factors of predictive value in HIV (human immuno-deficiency virus) seropositive patients, particular attention was payed to symptoms indicating early involvement of the central nervous system (CNS). A cohort of healthy carriers was thus constituted. Follow-up will be carried out every six month including clinical, biological as well as CNS imaging by NMR. Among the first 15 of them, abnormalities could be observed in 4 individuals. Lesions consisted in nodules of high signal in T2 which were localized either in the white matter or thalamic nuclei. No relationship could be demonstrated between the existence of these lesions and various criteria such as age, sex, risk factors and T4 cells count. Such lesions appeared similar to the localizations observed in multiple sclerosis or to the scars of limited vascular accidents. The nature of these lesions is not clear. They certainly indicate early involvement of CNS after primary infection by the HIV virus. They may either represent sequellae of this primary infection or early alterations announcing developing encephalopathy.

AIDS-Related Complex↗
PubMed1986

Mathematical morphology for automatic detection of brain lesions at magnetic resonance imaging.

An original method of image analysis has been developed, using 'mathematical morphology', in order to detect brain tumors at magnetic resonance imaging of the head following injection of gadolinium-DPTA. The main steps of the analysis are as follows: 1) Spatial reduction by automatic determination of a region of interest, 2) elimination of noise by morphologic filtering (increasing alternate closing-opening sequence), 3) localization of tumor by searching for r-h maxima, and 4) extraction of tumor contours using three-dimensional structuring elements. The preliminary results of this automatic and robust method encourage further studies of the potential of tissue analysis as an aid to tumor diagnosis.

Brain↗
PubMed1985

[Magnetic resonance imaging of the head compared with the CT scan].

After the description of the normal head anatomy in MRI and its exploration plans, the images observed in benign and malignant tumours of the brain, in cerebral ischaemic attacks, in the diseases of the orbit, face and skull base, are considered. The limits and present indications of the technique are defined.

Brain↗
PubMed1985

[Spinal forms of multiple sclerosis. Value and criticism of examination by cerebral magnetic resonance. Apropos of 4 cases].

Four observations of spinal forms of multiple sclerosis (MS) have been studied by Magnetic Resonance Imaging (MRI) (Magniscan Thomson CGR 0,15 and 0,5 T). They concerned 3 females and 1 male, aged between 29 and 60. Evolution of MS varied between 1 year and 9 years. There were no familial story of neurological illness; there were no signs and symptoms of visual, oculo-motor, labyrinthic and cerebellar disorders in the past. VEP were abnormal in 2 cases (no 1, 3), BAEP in 1 case (no 2). CSF examination showed increased gamma globulins with an oligoclonal pattern in 2 cases (no 3,4). CT Scan performed with iodine contrast injection was normal in 3 cases (no 2,3,4). In all the cases, MRI using T2 weighted-SE sequences, showed high signal lesions in the white matter of the brain and/or the cerebellum, and periventricular patchy white matter lesions. It seems to be no relationship between the duration of MS and the number of abnormal high signals areas, but more important series are necessary to confirm or not such a result. These lesions seem to be without aetiological specificity. They have to be discussed according to the clinical biological, electro-physiological data and sometimes others neuroradiological procedures.

Adult↗
PubMed1984

[Atlas of head anatomy in the neuro-ocular plane].

The "Atlas of cross-sectional orbito-cephalic anatomy in the neuro-ocular plane" does exist (now in press). The authors submit the main clinico-anatomical correlations observed. We will remind you that the "neuro-ocular plane" (N.O.P.) is defined as the C.T. plane of cephalic orientation comprising "both lenses, optic nerve heads and optic canals in the primary position of gaze". The more informative anatomical, radiological and anthropological data that could derive from the N.O.P. are stressed; first, we will evaluate the validity of our work and the problems we had while building the atlas; then we will describe briefly the position of this cephalic orientation plane as compared to other planes (specifically the anthropological baseline, the orbito-meatal line, the vestibular orientation etc...) previously described. Finally, we will end our discussion by giving the anatomical correlations obtained in the N.O.P.: this plane would best include all the visual pathways starting "from the cornea to the calcarine fissure"; it would also reflect the same orientation of the temporal horn of the lateral ventricle as well as the orientation of the lateral fissure. Much more, the orthogonality of this cephalic orientation to the direction of the brainstem is demonstrated, enhancing the accuracy of the three dimensional approach in the evaluation of the orbito-cephalic anatomy and diseases, as actually completed with C.T. and N.M.R. imaging, at the Centre National d'Ophtalmologie des XV-XX in Paris.

Anatomy, Artistic↗