Altitudinal Hemianopia: Lesion & Causes

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Upper Altitudinal Hemianopia
Upper Altitudinal Hemianopia

Altitudinal hemianopia comprises defective vision in the upper or lower horizontal half of the visual field. It may be unilateral or bilateral; unilateral field defect is prechiasmal.

Upper Altitudinal Hemianopia is caused as a result of destruction of bilateral destruction of lingual gyri.

Lower Altitudinal Hemianopia is caused as a result of destruction of bilateral destruction of cunei.

Lower Altitudinal Hemianopia

Causes

  1.  Anemia-produces bilateral inferior altitudinal hemianopia
  2. Anterior ischemic optic neuropathy
  3. Bilateral branch retinal artery occlusion
  4. Fusiform aneurysms (arteriosclerotic or congenital)-may produce inferior altitudinal hemianopia by pressure against the lateral halves of the optic chiasm or nerve
  5. Herpes zoster
  6. Lesion that presses the chiasm upward against the superior margin of the optic foramen
  7. Occipital lobe lesions
  8. Olfactory groove meningioma extending posteroinferior to compress the intracranial portion of the optic nerve
  9. Optic-nerve lesion
  10. Sclerotic plaques of internal carotid artery or anterior cerebral arteries-pressure of plaques on optic nerve results in inferior altitudinal hemianopia
  11. Following pars plana vitrectomy