Search PubMed⌕ Search

Biomedical subjects

A B Safran

Publications and source records attributed to A B Safran.

At least 91 records · Page 5Linked to original sources
PubMed1989

Late onset multiple sclerosis: clinical pattern of optic nerve involvement.

Multiple sclerosis presenting after age 50 is not rare as previously thought; it is associated with specific diagnostic difficulties, related to the age of the patient, and to the characteristically chronic progressive form of this condition. Therefore, diagnosis of MS related optic neuropathy should be considered in patients with unexplained loss of vision, even when apparent onset occurs after the age of 50.

Age Factors↗
PubMed1988

[Abnormalities of retinal function (light sense) following idiopathic central serous chorioretinopathy and diffuse retinal epitheliopathy].

Although central serous retinopathy is considered a "benign" condition, it is associated in healed forms with frequent and troublesome impairment of visual function. The abnormalities are even more severe after diffuse retinal pigment epitheliopathy. Since Snellen visual acuity testing is a relatively imprecise index of visual function, it does not enable the subtle visual disturbances experienced by these patients to be fully appreciated. The authors evaluated visual function disorders by static automated perimetry and contrast sensitivity in 30 patients with healed central serous retinopathy and in five patients with diffuse epitheliopathy at a cicatricial stage. The results of this study are examined and discussed.

Adult↗
PubMed1988

[Lesions of the posterior visual pathways: clinical presentation and mechanisms of functional restoration].

The present paper begins with a brief discussion of general clinical features found in patients with lesions of the posterior visual pathways. The author goes on to discuss various mechanisms of restitution of function in the central nervous system, including activation of neural pathways subserved by spared neurons, metabolic modulations, and neural plasticity.

Brain Damage, Chronic↗
PubMed1986

[Hypercoagulability syndrome associated with cerebral lesions. Prospective study of coagulation during surgery of primary brain tumors (17 cases)].

Variations in hemostatic factors have been studied in 17 patients undergoing neurosurgical operations for intracerebral primary tumors. Clotting time (plastic and glass), recalcification time (Howell), plasma fibrinogen level, fibrin split products, partial thromboplastin time, Quick and platelet count were measured before and after the surgical procedure and several times during the following 24 hours. Hemostasis was significantly disturbed, with maximal hypercoagulability 2 hours after operation. In 3 patients, fundus examination showed occlusion of retinal vessels. In all cases the surgical trauma was relatively minor compared with severe cerebral contusion, but was nevertheless enough to disturb the measured parameters, which appear to be sensitive indicators for assessing the severity of cerebral lesions, especially in cases of contusion. A systematic fundus examination is also of diagnostic interest. The state of blood hypercoagulability may lead to disseminated intravascular clotting (DIC) and therefore prophylactic heparin therapy should be administered.

Blood Coagulation↗
PubMed1985

Optic nerve hypoplasia: papillary diameter and clinical correlation.

Hypoplasia of the optic nerve is often subtle, and reduction in papillary diameter can be difficult to detect during ophthalmoscopic examination. Using a slit-lamp and a posterior fundus contact lens, we evaluated papillary diameter by bringing margins of the light beam to coincide with the limits of the optic nerve head. The method was standardized with 140 presumably normal eyes. Then we studied 17 consecutive eyes showing optic nerve hypoplasia. Hypoplasic discs were separated into two categories: (1) nine cases defined as having "moderate" hypoplasia, in which average disc diameters ranged between -2 and -2.5 standard deviations under the mean normal value; and (2) eight eyes with "severe" hypoplasia, showing average disc diameters less than the normal mean value by 2.5 standard deviations or more. Double peripapillary ring sign and low disc/artery ratio are clues often used in the diagnosis of optic nerve hypoplasia. The incidence of these signs was also evaluated in the hypoplasic discs studies. The double ring sign was present in two of the nine eyes with moderate hypoplasia, and in seven of the eight eyes with severe hypoplasia. Of eight eyes with moderate hypoplasia, only one showed a disc/artery ratio inferior to the mean normal value -2 standard deviations, whereas this ratio was significantly reduced in all cases of severe hypoplasia. These ophthalmoscopic clues therefore appear to be much less valuable than direct measurement of the optic disc for detecting a subtle reduction in disc diameter. This is of particular interest when one considers that all the nine eyes with moderate hypoplasia had alteration in visual function upon presentation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

Lagophthalmos in acquired oculomotor synkinesis.

Two consecutive patients who exhibited classic signs of unilateral acquired oculomotor synkinesis demonstrated an inability to appose eyelid margins on the affected side, when attempting gentle closure of the eyes. In one patient, this occurred in conjunction with a unilateral upper eyelid crease on the affected side, and in the other patient it was associated with accentuation of the crease in comparison with that of the opposite side. Bilateral eyelid closure normally induces a contraction of the superior recti muscles. The lagophthalmos and accentuated upper eyelid crease observed in our patients when they attempted gentle eyelid closure presumably resulted from inappropriate coactivation of the levator palpebrae superioris muscle by impulses destined for the superior rectus muscle.

Adult↗
PubMed1984

Macular reflexes in optic atrophy.

We investigated the annular reflex of the macula and the foveal reflex in 14 eyes with various degrees of optic atrophy by means of red-free fundus photographs. The patients ranged in age from 13 to 34 years (mean age, 25.9 years). We compared our observations with data obtained from 51 age-matched normal eyes. Optic atrophy was found to be associated with changes in the reflexes of the macular area. Alterations occurred in all eight eyes that had visual acuities of 20/50 or worse. Changes in the annular reflex of the macula were more significant in younger patients (less than or equal to 25 years of age) than in older patients. In the younger group, the annular reflex was blunt, distorted, and fragmented, and showed an irregular extension toward the foveal area, whereas in the old group it showed less specific attenuation. Fading of the foveal reflex was observed in both groups. Changes in the retinal reflexes of these patients result from alterations in the ganglion cell and nerve fiber layer and should be included among the signs of optic atrophy. They can help determine the extent of optic atrophy and can be useful clinical clues in children whose optic disks are difficult to examine. They should not be mistaken for signs of associated primary retinal disorders.

Adolescent↗
PubMed1984

Evaluation of visual function in healthy subjects after administration of Ro 15-1788.

Ro 15-1788 is a specific benzodiazepine antagonist, which has also been shown to have some agonist properties. Since benzodiazepine receptors are involved in the physiological mechanisms of vision, a possible intrinsic effect of Ro15-1788 was sought in 6 healthy volunteers by study of psychophysical flicker thresholds, including critical fusion frequency and low frequency modulation threshold, and pattern reversal visual evoked response, using double blind cross-over methodology. In each session 2 tablets of Ro 15-1788 30 mg were administered. Using a two factorial univariate analysis of variance, no change was detected in any of the parameters studied.

Adult↗