What are visual pathway disorders?
What are visual pathway disorders?
Patients may report monocular or binocular blurred, blank, dim, dark, or sparkling vision. Optic nerve damage may be accompanied by swollen optic disc. Unilateral or asymmetric optic nerve damage produces afferent pupil defect. Lesions of optic nerve produce nerve fiber bundle visual field defects.
What is the afferent pathway for vision?
The afferent visual pathways encompass structures which perceive, relay, and process visual information: the eyes, optic nerves (cranial nerve II), chiasm, tracts, lateral geniculate nuclei, optic radiations, and striate cortex.
What is afferent visual system?
The afferent visual pathway is related to the sensory aspect of vision and involves all the structures responsible for receiving, transmitting, and processing visual information.
What happens if the optic chiasm is damaged?
If the optic nerve is damaged in the optic chiasm level, it causes bitemporal hemianopia. This may occur in expanding pituitary adenoma (Figure 1). If optic nerve is damaged posterior to the optic chiasm (optic tract, optic radiation), it causes a visual field defect on the opposite side to the damage [5-7].
What is the function of visual pathway?
The visual pathway refers to the anatomical structures responsible for the conversion of light energy into electrical action potentials that can be interpreted by the brain. It begins at the retina and terminates at the primary visual cortex (with several intercortical tracts).
What is Heteronymous hemianopia?
Heteronymous hemianopia. This is the area in your brain where the optic nerves cross and form an “X.” The two types of heteronymous hemianopia are bitemporal and binasal. Bitemporal hemianopia is when you lose vision in the outer half of each eye.
What is retinal problem?
A retinal disorder or disease affects this very important tissue, which, in turn, can affect vision to the point of blindness. Common retinal conditions include floaters, macular degeneration, diabetic eye disease, retinal detachment, and retinitis pigmentosa.
Is involvement of the other eye common in AAION defects?
Involvement of the other eye is common during the course of the disease. treatment is essential in AAION! defects is possible with timely treatment. JD Trobe. Neuro-ophthalmology.
What is the pathophysiology of visual lesions of the eye?
Lesions of the visual pathway may lead to visual disturbances or visual loss, the pattern of which can assist in determining the exact location of the lesion. Unilateral visual field loss indicates a prechiasmal pathology, while bilateral visual field loss indicates a chiasmal or retrochiasmal
What causes unilateral loss of vision in retinal lesions?
Lesions of the may lead to visual disturbances or visual loss, the pattern of which can assist in determining the exact location of the lesion. Unilateral loss indicates a chiasmal or retrochiasmal pathology. Retinal diseases mostly cause central or paracentral .
