hemianopsia


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Related to hemianopsia: binasal hemianopsia

hemianopia

 [hem″e-ah-no´pe-ah]
defective vision or blindness in half of the visual field; usually applied to bilateral defects caused by a single lesion. adj., adj hemianop´ic, hemianop´tic.
Patient Care. Visual field deficit on one side often occurs as a result of stroke syndrome. Patients with this problem are unable to perceive objects to the side of the visual midline. The visual loss is contralateral, i.e., it is on the side opposite the brain lesion. To facilitate self care, commonly used articles such as the water pitcher, meal tray, and call bell are placed on the unaffected side. The patient should be approached from and communicated with while standing or sitting on the side in which vision is best. When in visual contact with the patient, caregivers should move slowly toward and past the visual boundary to stimulate scanning to the affected side. Auditory and visual stimulation on the affected side can help improve and maintain residual sight on that side.
Visual field defects associated with hemianopia. From Polaski and Tatro, 1996.
homonymous hemianopia hemianopia affecting the right halves or the left halves of the visual fields of both eyes. The patient must turn the head from side to side to compensate for the defect. Often it is due not to any pathology in the eye itself but to damage to the optic tract or occipital lobe.

hem·i·a·no·pi·a

(hem'ē-ă-nō'pē-ă),
Loss of vision for one half of the visual field of one or both eyes.
Synonym(s): hemianopsia

hemianopia

Loss of vision in one half of the visual field of one eye (unilateral hemianopia) or of both eyes (bilateral hemianopia) (Fig. H1). Syn. hemianopsia. See quadrantanopia; hemianopic pupillary reflex.
absolute hemianopia Hemianopia in which the affected part of the retina is totally blind to light, form and colour.
altitudinal hemianopia Hemianopia in either the upper or lower half of the visual field. A common cause is anterior ischaemic optic neuropathy.
binasal hemianopia Hemianopia in the nasal halves of the visual fields of both eyes.
bitemporal hemianopia Hemianopia in the temporal halves of the visual fields of both eyes.
congruous hemianopia Hemianopia in which the defects in the two visual fields are identical. A common cause is a lesion in the posterior optic radiations.
heteronymous hemianopia A loss of vision in either both nasal halves (binasal hemianopia) or both temporal halves of the visual field (bitemporal hemianopia). A common cause of the latter is a lesion in the optic chiasma.
homonymous hemianopia A loss of vision in the nasal half of the visual field of one eye and the temporal half of the visual field of the other eye. Left homonymous hemianopia is a loss of vision in the temporal half of the visual field of the left eye and the nasal half of the visual field of the right eye. Right homonymous hemianopia is a loss of vision in the temporal half of the visual field of the right eye and the nasal half of the visual field of the left eye. Common causes are occlusion of the posterior cerebral artery (stroke), trauma and tumours. See macular sparing.
incongruous hemianopia Hemianopia in which the defects in the two affected visual fields differ in one or more ways. A common cause is a lesion of the optic tract.
quadrantic hemianopia See quadrantanopia.
relative hemianopia Hemianopia involving a loss of form and colour but not of light.
hemianopia spectacles See hemia-nopic spectacles.
Fig. H1 Complete, bitemporal hemianopia due to a large pituitary tumour compressing the optic chiasmaenlarge picture
Fig. H1 Complete, bitemporal hemianopia due to a large pituitary tumour compressing the optic chiasma
References in periodicals archive ?
La hemisferectomia es la intervencion de eleccion; sin embargo, el propio acto quirurgico conlleva un riesgo y las secuelas se haran presentes, como hemianopsia homonima contralateral, hemiplejia espastica contralateral, perdida del movimiento fino de las manos, crisis residuales y trastornos del lenguaje.
El test consiste en el avance de un cateter femoral llevado hasta las carotidas internas de igual forma que en un estudio de angiografia cerebral, inyectando en cada carotida interna de manera separada e independiente amital sodico, alrededor de 100 mg, el cual producira de manera casi instantanea anestesia del hemisferio ipsilateral a la inyeccion, que produce hemiplejia con hemihipoestesia, hemianopsia y alteraciones del lenguaje segun el lado inyectado.
Binasal hemianopsia, unlike types of visual field loss such as bitemporal heteronymous hemianopia, unilateral homonymous hemianopia, is not common and cannot be explained by a single visual tract lesion.
Neurological examination of the patient revealed left hemiparesis, dysarthria, and homonymous hemianopsia of the left side with a National Institutes of Health Stroke Scale of 12.
He could only finger count in the right eye and had an additional bitemporal hemianopsia on visual field testing.
Additional ocular manifestations were diplopia (18 patients, presenting manifestation in 16 patients), ptosis (8 patients), papilledema (4), anysocoria (3), exophthalmos (2), orbital pain (2), scotomas (2), hemianopsia (1), and nystagmus (1).
The most common visual field disturbance is bitemporal hemianopsia, and contiguous spread of the tumor to the adjacent cavernous sinus most commonly produces cranial nerve III and IV dysfunction (1).
Cualquier region del SNC puede estar afectada, sin embargo se encuentra tropismo por algunas regiones, como los lobulos occipitales (produciendo hemianopsia), los lobulos frontales y parietales (hemiparesia y deficit sensoriales), los pedunculos cerebelosos y la sustancia blanca profunda (dismetria y ataxia).
No hay datos de alteracion de los campos visuales como hemianopsia o cuadrantopsia para pensar en compromiso del quiasma optico y no hay referencia de cataratas por retinologia.
He has poorly controlled type II diabetes mellitus; obesity (body mass index 40 kg/ [m.sup.2] ); complicated cryptogenic cirrhosis with prior esophageal varices, portal gastropathy, splenomegaly, and no encephalopathy; surgically treated colon adenocarcinoma; and bilateral thalamic and right occipital infarcts with residual left homonymous hemianopsia and vertical gaze paresis.
(3,4) The subsequent neurologic deficits can manifest as partial or complete hemiparesis, homonymous hemianopsia, Horner's syndrome, facial nerve paralysis, gait issues, or death.
Visual field examination revealed upper temporal quadrantanopsia on the right side and incomplete temporal hemianopsia on the left side, whereas other neurological examinations were normal.