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At least 109 records · Page 6Linked to original sources
PubMed1990

Age-related maculopathy. I: A review of its morphology and effects on visual function.

Age-related maculopathy (ARM) is a leading cause of permanent vision loss in elderly people. ARM therefore constitutes an important public health problem which will increase in magnitude as the number of aged people in the general population becomes greater. The consequences of this condition are exacerbated by the fact that treatment, especially of the atrophic form of the disease, is ineffective. While laser photocoagulation may be helpful in the exudative form of ARM, there is often an inexorable progression towards severe vision loss in these patients. Therefore considerable attention needs to be paid to the aetiology of ARM, the potential for its prevention or delayed onset and its recognition through functional disturbances. This is the first of three papers dealing with ARM and its effects on visual function. We review its morphology and the visual disturbances that may ensue. The second and third papers will discuss the nature and detection of the central visual field loss due to ARM.

Aging↗
PubMed1990

Visual function improvement in patients with macroprolactinomas treated with bromocriptine.

We studied eight patients who had visual field defects secondary to prolactin-secreting macroadenomas and who had improved visual function with bromocriptine treatment without surgery or radiation. We recommend bromocriptine as a primary treatment for prolactin-secreting macroadenomas. If therapy is effective, continued regular neuro-ophthalmologic, endocrine, and imaging studies are necessary, because treatment with bromocriptine must be continued indefinitely.

Adult↗
PubMed1985

Visual function in prolactinoma patients treated with bromocriptine.

Ten patients with prolactin-secreting pituitary adenomas (prolactinoma) and visual dysfunction were treated primarily with bromocriptine. Nine patients had improvement of visual field or acuity associated with computed tomography (CT) evidence of a decrease in tumor size and reduction of serum prolactin level (SPL). Visual improvement usually began within days of commencing bromocriptine therapy. One patient with initial improvement had a worsening of visual fields at 11 months despite a normal SPL and a stable CT appearance of tumor size. This patient and the single patient without visual improvement underwent trans-sphenoidal hypophysectomy (TSH), but neither patient had postoperative visual improvement. Two other patients underwent TSH for nonvisual reasons. The remaining six patients have maintained excellent visual function at last follow-up (average of 18 months on bromocriptine therapy). This study shows that bromocriptine is an effective short- and long-term therapy for most patients with visual dysfunction due to prolactinoma.

Adult↗
PubMed1978

Use of the argon aiming beam in visual function testing.

The aiming beam of the argon laser photocoagulator can be a useful tool in visual function testing. Applied with the slit lamp delivery system and fundus contact lens, it clearly documents the size of the blind spot surrounding the optic nerve head and the normal area of nonfunctional retina in the periphery. The size of pathologic field defects can be recorded on fundus photographs or retinal drawings by an observer. Safety precautions must be taken to protect all patients from excessive laser energy.

Argon↗
PubMed1989

[Detection of latent disorders of visual function during ambulatory care of children].

For the purpose to select tests for diagnosis of latent disturbances of visual functions, dynamic observation was conducted over 88 healthy school children within 5 years (from the 3d to the 8th form). Once a year, the children underwent examination of visual acuity for far and near, the state of binocular vision on a synoptophore and a color test, the volume of relative and absolute accommodation, muscular balance of eyes for far and near, contrast sensibility, the time of perception of the negative successive contrast, refraction. For the period of 5 years, 7 children developed myopia of low degree, 32 showed transitory or lasting reduction of visual acuity due to spasm of accommodation. The authors believe that the most rapid and informative tests for diagnosis of latent disturbances in accommodation-convergence system are visual acuity for near, the volume of absolute accommodation, the threshold of remote vision, muscular balance of eyes for near. It is recommended to use these tests widely when conducting ophthalmologic thorough prophylactic examinations of children.

Ambulatory Care↗
PubMed1985

Joint application of hyperacuity perimetry and gap tests to assess visual function behind cataracts: initial trials.

We have developed two related clinical tests that offer potential in better assessing visual function behind an ocular opacity. The tests are resistant to the effects of opacities because they utilize a localization task (vernier acuity) rather than a resolution task. In this paper we report the initial trials in which we apply the two tests together. Results from six case studies (some with actual opacities and some with simulated opacities) illustrate both the conduct of the tests and their potential capabilities in detecting even very modest retinal dysfunction in the presence of opacities. These techniques offer considerable potential in the separation of a given acuity loss observed in the presence of cataract into a portion due to the opacity and a portion due to retinal dysfunction.

Aged↗
PubMed1992

Assessment of central visual function after successful retinal detachment surgery by pattern visual evoked cortical potentials.

The pattern of visual recovery after successful surgery by pattern visual evoked cortical potentials (VECP), visual acuity, colour vision, and critical fusion frequency was investigated in 14 eyes with retinal detachment involving the macula. The temporal tuning characteristics in the evoked potentials were measured as based on the P100 amplitude and the frequency necessary for evoking 0 mu V amplitude, which was defined as an objective critical fusion frequency by extrapolating the curve. Significant improvement in visual acuity and colour vision was observed within 2 months postoperatively. A significantly increased P100 peak latency became shorter as the postoperative days increased. In general, a good correlation was noted between the P100 peak latency and subjectively measured visual acuity, colour vision, and critical fusion frequency. The objective critical fusion frequency measured by VECP recovered gradually during the 6 months after surgery. Functional recovery was not related to the length of time the macula was detached before surgery.

Adolescent↗
PubMed1976

Developing visual function in the red jungle fowl embryo.

The onset of visual system function in the wild red jungle fowl embryo was measured by the pupillary reflex technique and compared with its domesticated descendant, the domestic chick. The first neurally mediated pupillary reflex in the jungle fowl embryos was found at Day 15 of incubation after 77% of incubation was completed. This point did not differ significantly from the onset of this reflex in the domestic chick embryo (after approximately 83% of incubation). Thus, it was concluded that the relatively late onset of overt visual system function in the chick, as compared with several other precocial avian species, was not a result of its history of intense domestication but rather was most likely a normal characteristic of this and other closely related species.

Age Factors↗
PubMed1990

[Dynamics of visual functions in the conditions of glow and sodium lighting. I. Visual acuity, accommodation, flicker fusion, visual field and heterophoria].

Investigations of the functions cited in the title were performed in 23 persons with a normal visual system in conditions of equal illumination, first the glow and the next day or later--the sodium one. All the tests were carried out three times in the morning hours evaluating in this way their dynamics as the time goes. The authors are analyzing the degree of the variability of the discussed functions in the time, as well as their behaviour in conditions of applied illumination. The results obtained suggest that in conditions of illumination by a high-pressure sodium lamp no negative characteristics of this source of light emerged. Deterioration of a small degree was observed only in the range of accommodation for near.

Accommodation, Ocular↗
PubMed1992

[Visual function damage in primary open angle glaucoma (POAG) in relation to hemorheology, ocular rheograph and other factors].

Researches of glaucomatous visual damage, hemorheology, ocular rheograph and other multiplex factors, with computed multifactorial stepwise regression analysis, indicate that elevation of intraocular pressure (IOP) is not the only factor to induce visual impairment. POAG patients are shown to have markedly reduced diastolic perfusion pressure in the ophthalmic artery, besides prolonged filling time of the retinal artery and vein, diminished erythrocyte deformability and increased platelet adhesion rate. The characteristic ocular rheographic changes in POAG patients of controlled IOP suggest that hemorheological factors play a role in the visual function damage.

Adult↗
PubMed1991

Does the lymph drainage from the head influence aqueous humour outflow and visual functions?

Effect of lymphoedema of the head on the central nervous system is known. Possible changes in intraocular pressure, tonogram, electroretinogram, visual functions and ophthalmologic state was studied in animal experiments and in patients following serious surgical impairment of the cervical lymph drainage. Lymph drainage from the orbit to the deep cervical lymphatics was established, while no ophthalmologic alteration was detected after surgery.

Animals↗
PubMed1989

[Postoperative recovery of visual function in sella tumors: prognostic assessment by electro-ophthalmologic studies].

Preoperative examination of the visual system in patients with tumors of the sellar region is usually limited to checking the visual acuity, assessing the visual field, and ophthalmoscopy of the optic disc. In addition to these tests we investigated pre- and postoperatively 35 patients with meningiomas, pituitary adenomas and other sellar and parasellar tumors by recording the pattern electroretinogram (PERG) and the pattern-evoked cortical potential (PVECP) in order to evaluate functional and possible structural impairment of the visual pathway. Based on electro-ophthalmological tests, the retinal and cortical findings were classified as: regular ERG and VECP (0), regular ERG and irregular VECP (1), irregular ERG and VECP (2). Up to six months postoperatively, eyes with alteration of the VECP alone (category 1) showed recovery of visual function, while those with alteration of ERG as well (category 2) did not recover in visual function. Since loss of the PERG or long-lasting alteration of it is indicative of irreversible impairment of the inner retinal layers including the retinal ganglion cells, repeat examination of the pattern ERG is recommended in disturbances caused by alterations in the central nervous system.

Adenoma↗
PubMed1978

Visual function in acute posterior multifocal placoid pigment epitheliopathy.

We examined a 19-year-old woman with acute posterior multifocal placoid pigment epitheliopathy one week after she noted blurring of central vision. Her corrected visual acuity was R.E.: 6/7.5 (20/25), and L.E.: 6/12 (20/40). The visual fields showed 10-degree pericentral scotomas. A color vision defect and an abnormal Stiles-Crawford effect were present. Dark adaptation showed a delayed time course, with normal final thresholds. The electro-oculogram was subnormal, suggesting widespread abnormality of the retinal pigment epithelium. Active lesions resolved within three weeks, but fluorescein angiography showed characteristic widespread residual changes. Within three weeks, she had normal visual acuity and a normal electro-oculogram. Other tests of visual function showed recovery with a slower time course. By one year, the visual fields, color matching, Stiles-Crawford effect, and dark adaptation were almost normal. Analysis of the color-matching data and Stiles-Crawford effect indicated that the abnormalities of macular function were caused by an underlying lesion of the pigment epithelium and photoreceptors. This caused a physical distortion of the photoreceptor layer and metabolic disfunction of the photoreceptors.

Adult↗
PubMed1987

Analysis of binocular visual function using tests made under binocular conditions.

Accommodation and vergence have a complex relation which occasionally breaks down, resulting in a loss of visual efficiency along with symptoms of discomfort associated with use of the eyes. Studies of accommodation/vergence interactions and tonic vergence disorders indicate that, using classical analysis techniques, separate methods are frequently necessary to determine whether existing binocular deficiencies are causing reported symptoms. The problem with current systems of binocular visual function analysis is that the vergence error which exists under binocular conditions is often not the same as that which is measured under monocular conditions. A rationale for, and technique of, analyzing binocular function using results of tests made under binocular conditions is described. This analysis incorporates the concepts of CA/C, proximal vergence (PV), and fixation disparity along with several accommodative measures (facility, lag, sustaining ability, and accuracy). By identifying relevant binocular components and the interrelations, the clinician should be better able to assess the contribution of each and examine which may be modified most easily by vision therapy, lenses, and/or prism intervention.

Accommodation, Ocular↗
PubMedDate not supplied

Functional visual loss in Cambodian refugees: a study of cultural factors in ophthalmology.

South East (SE) Asians accounted for a disproportionate percentage of the functional visual loss (FVL) seen in our area between 1983 and 1987. Moreover, 94% of the SE Asian FVL patients were Cambodian, although Cambodians only represented 20-30% of the local SE Asian patient population. Cambodian refugees are, at present, generally from lower socio-economic classes than the Vietnamese, and a much larger percentage of them have a history of camp incarceration and previous trauma. The Cambodians presenting with FVL may have conversion hysteria influenced by their wartime experience and cultural background. This study demonstrates that the SE Asian refugees in California are not a homogenous group with respect to visual problems, and that an awareness of cultural or historical factors can be important to the management of ophthalmic symptoms in our multi-cultural societies.

Adult↗
PubMed1978

Pituitary adenoma and visual function. The prognostic value of clinical, ophthalmological and neuroradiologic findings in 51 patients subjected to operation.

The series studied included 51 patients subjected to operation for pituitary adenoma. The visual status was analysed both pre- and postoperatively. The pre- and postoperative parameters were compared with clinical information, ophthalmological and neuroradiological findings with a view to an evaluation of their prognostic value. In 36 patients with chromophobe adenoma, visual field defects were present in 92% before the operation; visual function improved in 62% and returned to normal in 24%. Among 15 patients with eosinophil or mixed adenoma, only two (13%) had visual field defects pre-operatively. In those patients where operation was followed by a distinct visual improvement, the pre-operative ophthalmological findings were as follows: visual acuity greater than 6/24, normal optic discs, visual field defects up to two quadrants, and pneumoencephalographic findings suggestive of only a small suprasellar tumour.

Adenoma↗
PubMed1991

Long-term visual function in acute posterior multifocal placoid pigment epitheliopathy.

Acute posterior multifocal placoid pigment epithellopathy is a chorioretinal inflammatory disease occurring in young, healthy adults. The long-term visual prognosis and recurrence rate is uncertain. We reexamined 28 patients (53 affected eyes) with acute posterior multifocal placoid pigment epitheliopathy (mean follow-up, 8 years) to obtain details on the long-term functional visual outcome. The final visual acuities were 20/25 or better in 48 eyes (90.6%), 20/30 to 20/100 in four eyes (7.5%), and 20/200 in one eye (1.9%). Although the final visual acuity was good, 33 eyes (62.3%) were symptomatic with blurred vision, metamorphopsia, or scotomas. Thirty-six eyes (67.9%) had significant central visual field defects on follow-up examination. There were no recurrences after the initial month of symptoms. The chorioretinal scars did not enlarge with time. Acute posterior multifocal placoid pigment epitheliopathy has a good longterm prognosis for visual acuity, although most patients have residual symptoms and paracentral scotomas.

Acute Disease↗