Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0028738 (nystagmus)
 7,431 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It is concluded that measurement of visual readaptation time (RAT) using optokinetic nystagmus (OKN) is a repeatable measure of visual recovery after flash exposure. The semi-automatic method for measurement of RAT used here requires further development, but it is anticipated that the improved method will provide an efficient tool for increased understanding of the physiology of flash blindness. In this study on humans, it was found that if RAT is recorded twice on the same occasion, the second RAT is shorter. However, there was no systematic difference between RAT recordings on consecutive occasions. The newly developed semi-automatic method was found to provide RATs comparable to those obtained by manual measurement on a paper print out of EOG recordings. In RAT estimation, the variability between subjects shadows other sources of random variability. The least number of subjects needed in each group to detect a 20% alteration of RAT due to an experimental factor (alpha = 0.05, beta = 0.05) was estimated to 13 with independent groups design. For paired design < 10 are needed. OKN was elicited with a horizontally moving vertical grating. The eye movement was recorded by DC EOG. A sudden flash of green light temporarily abolished the OKN. The internal between the flash and the reappearance of OKN was measured as the RAT.
 ...
PMID:Measurement of visual readaptation time after flash exposure using optokinetic nystagmus. 815 58

Despite the well-recognized association between maternal varicella infection and a specific pattern of malformation in the offspring referred to as fetal varicella syndrome, the full spectrum of this disorder as well as its frequency in the offspring of women infected with varicella during pregnancy is unknown. In order to resolve these issues, we have evaluated pregnancy outcome in 194 women who contacted us during pregnancy, soon after the onset of their infection: 132 (68%) during the 1st trimester and 171 (88%) prior to the onset of the 20th week, the most critical period relative to fetal susceptibility. Of those 171 women, there were 146 liveborn babies, 6 spontaneous abortions, 7 therapeutic abortions (one because of an anencephalic fetus), 2 stillborn infants, and nine pregnancies lost to follow-up. Of the 146 liveborn births, there were 2 with features consistent with the fetal varicella syndrome: one a child with mild cutaneous scars on her face, arms, and legs, Horner syndrome involving her left eye and a scar on her retina, leading to blindness in that eye; and the other, a child with horizontal nystagmus who is otherwise normal at 1 year of age. An additional four liveborn infants had a single major malformation which included unilateral microtia, bowel obstruction secondary to an ileal band, bilateral double ureters, and a thyroglossal duct cyst. This study suggests that prenatal varicella infection is associated with a wider spectrum of severity than has been previously appreciated and indicates that maternal varicella infection prior to the 20th week of pregnancy is associated with only a small risk for the developing fetus.
 ...
PMID:Offspring of women infected with varicella during pregnancy: a prospective study. 817 94

The case of a chronic alcoholic patient with Wernicke's encephalopathy accompanied by passing blindness is reported and the alcoholic amblyopia is discussed in this study. The patient was a 39 year-old male who had been a heavy drinker for 13 years, and was habitually inebriated for the last one year. Disturbance of consciousness ataxia of gait, nystagmus and blindness were manifested on admission. Decreased level of serum vitamin B1 was also recognized at admission. The symptoms diminished from about a month after admission except for horizontal nystagmus. Since the patient had racket-like scotoma in his central visual field, his blindness was thought to be alcoholic amblyopia. Although alcohol dependence is associated with many physical disabilities, there are few reports about Wernicke's encephalopathy with alcoholic amblyopia. This case demonstrates the importance of careful physical examination for understanding alcohol-related disabilities and alcohol dependence.
 ...
PMID:[A case of Wernicke's encephalopathy which accompanied a passing blindness]. 819 11

Neuro-ophthalmologic problems are some of the most distressing ocular conditions to affect children. In this article the author discusses the differential diagnosis and management of blindness during the first year of life. Nystagmus or 'jiggling eyes' tumors of the visual pathways and acquired ocular motor neuropathies comprise the balance of the article.
 ...
PMID:Common pediatric neuro-ophthalmologic conditions. 834 66

Primary tumors of the pineal body can produce dyscoordinative movements of the eye, pupillary dilatation, paralysis of adduction during convergence and nystagmus. Obstruction of the aqueduct can cause hydrocephalus, increased intracranial pressure and papilledema. Diabetes insipidus may be a presenting symptom. Pinealocytes and the photoreceptors of the eye contain several autoantigens. In man, the best known is the S-antigen. This antigen can be detected in the cerebrospinal fluid of patients with primary tumors of the pineal body. The S-antigen, and possibly other related autoantigens, can elicit an autoimmune mediated reaction causing inflammatory eye symptoms. This recently described paraneoplastic neurologic syndrome shares properties in common with other known cancer-associated ophthalmologic syndromes characterised by rapid development of eye symptoms, rapid loss of sight and by eye manifestations prior to evident appearance of symptoms related to primary tumor growth. A primary tumor of the pineal body should be considered in patients where a monosymptomatic uveoretinitis presents without associated provoking factors. Furthermore, analyses of S-antigen in the spinal fluid can be useful in the clinical diagnosis of the same primary tumors.
 ...
PMID:[Physiopathologic mechanisms behind eye symptoms in primary tumors of the pineal body]. 843 Apr 65

Anatomic elements of the retrochiasmatic pathway. Synopsis of homonymous pathway. Synopsis of homonymous hemianopia: unilateral forms [quadrant, total], bilateral forms [tunnel field, cerebral blindness], homonymous scotomas, horizontal hemianopsias, checkerboard hemianopsias, sparing of temporal crescent. Additional disorders: hemi-neglect, color agnosia, hemi-achromatopsia, alexia, abnormal optokinetic nystagmus, cog-wheel pursuit movement, hemianopic pupillary defect, statokinetic dissociation [Riddoch phenomenon], hallucinations, illusions, visual agnosia, prosopagnosia.
 ...
PMID:[Vision disorders in retrochiasmatic lesions of the visual pathways]. 865 Jun 20

An outbreak of polioencephalomalacia affected 16 of 46 Swaledale lambs and five of 25 Scottish blackface lambs 15 to 32 days after they were introduced to an ad libitum concentrate ration containing 0.43 per cent sulphur. The clinical signs were acute and included depression central blindness and head-pressing, but no hyperaesthesia, nystagmus, dorsiflexion of the neck or opisthotonos were observed. Treatment of the affected lambs with vitamin B1, dexamethasone and antibiotics was associated with a prolonged recovery period, though no further cases were identified after vitamin B1 had been given parenterally to all the lambs at risk.
 ...
PMID:Sulphur-induced polioencephalomalacia in lambs. 873 Jun 74

Congenital ocular motor apraxia (C-OMA) is an infrequently reported eye movement disorder associated with malformation or delayed maturation of the brain. Patients with C-OMA are unable to initiate voluntary horizontal saccades. This results in characteristic head thrusts into the desired field of gaze to compensate for the lack of saccadic ability. Careful examination of an 8-year-old Hispanic male revealed uncoordinated eye movements, lack of voluntary saccades, head thrusts, and gross/fine motor delays all consistent with congenital ocular motor apraxia. Torsional oscillations that resembled rotary nystagmus were also present. These have not been previously reported in association with C-OMA. Because young patients with this condition may appear to have cortical blindness, C-OMA is an important differential to be aware of in making a diagnosis.
 ...
PMID:Congenital ocular motor apraxia with torsional oscillations: a case report. 874 43

Leber's congenital amaurosis (LCA, MIM 204,000), the earliest and most severe form of inherited retinopathy, accounts for at least 5% of all inherited retinal dystrophies. This autosomal recessive condition is usually recognized at birth or during the first months of life in an infant with total blindness or greatly impaired vision, normal fundus and extinguished electroretinogram (ERG). Nystagmus (pendular type) and characteristic eye poking are frequently observed in the first months of life (digito-ocular sign of Franceschetti). Hypermetropia and keratoconus frequently develop in the course of the disease. The observation by Waardenburg of normal children born to affected parents supports the genetic heterogeneity of LCA. Until now, however, little was known about the pathophysiology of the disease, but LCA is usually regarded as the consequence of either impaired development of photoreceptors or extremely early degeneration of cells that have developed normally. We have recently mapped a gene for LCA to chromosome 17p13.1 (LCA1) by homozygosity mapping in consanguineous families of North African origin and provided evidence of genetic heterogeneity in our sample, as LCA1 accounted for 8/15 LCA families in our series. Here, we report two missense mutations (F589S) and two frameshift mutations (nt 460 del C, nt 693 del C) of the retinal guanylate cyclase (RETGC, GDB symbol GUC2D) gene in four unrelated LCA1 probands of North African ancestry and ascribe LCA1 to an impaired production of cGMP in the retina, with permanent closure of cGMP-gated cation channels.
 ...
PMID:Retinal-specific guanylate cyclase gene mutations in Leber's congenital amaurosis. 894 27

A 79-year-old woman with persistent cortical blindness caused by bilateral temporo-occipital infarctions was followed for 8 months. She had no light or visual motion perception. Our patient's visual imagery was intact, which was demonstrated when drawing elementary shapes; however, her drawing of objects was poor. Optokinetic nystagmus could not be elicited, but the vestibulo-ocular reflex (VOR) seemed intact. Although she was able to suppress her VOR by 'fixating' her outstretched hand which moved in phase with her head and body, she showed saccadic tracking eye movements in an attempt to visually 'follow' the self-generated movements of her outstretched hand, while her body and head were stationary. Such saccadic tracking seemed to be different from the previously described smooth tracking of self-moved targets by patients with acquired blindness caused by anterior visual pathway dysfunction.
 ...
PMID:Cortical blindness. 949 7


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>