Bitemporal hemianopia: Difference between revisions

Jump to navigation Jump to search
No edit summary
Line 44: Line 44:
===Common causes===
===Common causes===
*[[Pituitary tumor|Pituitary macroadenoma]]
*[[Pituitary tumor|Pituitary macroadenoma]]
*[[Craniopharyngoma]]
*[[Craniopharyngioma]]
*[[Meningioma]]
*[[Meningioma]]
*[[Aneurysm]] of anterior communicating artery
*[[Aneurysm]] of anterior communicating artery

Revision as of 08:51, 15 July 2012

Template:DiseaseDisorder infobox

Paris as seen with full visual fields

WikiDoc Resources for Bitemporal hemianopia

Articles

Most recent articles on Bitemporal hemianopia

Most cited articles on Bitemporal hemianopia

Review articles on Bitemporal hemianopia

Articles on Bitemporal hemianopia in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Bitemporal hemianopia

Images of Bitemporal hemianopia

Photos of Bitemporal hemianopia

Podcasts & MP3s on Bitemporal hemianopia

Videos on Bitemporal hemianopia

Evidence Based Medicine

Cochrane Collaboration on Bitemporal hemianopia

Bandolier on Bitemporal hemianopia

TRIP on Bitemporal hemianopia

Clinical Trials

Ongoing Trials on Bitemporal hemianopia at Clinical Trials.gov

Trial results on Bitemporal hemianopia

Clinical Trials on Bitemporal hemianopia at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Bitemporal hemianopia

NICE Guidance on Bitemporal hemianopia

NHS PRODIGY Guidance

FDA on Bitemporal hemianopia

CDC on Bitemporal hemianopia

Books

Books on Bitemporal hemianopia

News

Bitemporal hemianopia in the news

Be alerted to news on Bitemporal hemianopia

News trends on Bitemporal hemianopia

Commentary

Blogs on Bitemporal hemianopia

Definitions

Definitions of Bitemporal hemianopia

Patient Resources / Community

Patient resources on Bitemporal hemianopia

Discussion groups on Bitemporal hemianopia

Patient Handouts on Bitemporal hemianopia

Directions to Hospitals Treating Bitemporal hemianopia

Risk calculators and risk factors for Bitemporal hemianopia

Healthcare Provider Resources

Symptoms of Bitemporal hemianopia

Causes & Risk Factors for Bitemporal hemianopia

Diagnostic studies for Bitemporal hemianopia

Treatment of Bitemporal hemianopia

Continuing Medical Education (CME)

CME Programs on Bitemporal hemianopia

International

Bitemporal hemianopia en Espanol

Bitemporal hemianopia en Francais

Business

Bitemporal hemianopia in the Marketplace

Patents on Bitemporal hemianopia

Experimental / Informatics

List of terms related to Bitemporal hemianopia

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] ; Aditya Govindavarjhulla, M.B.B.S. [2]

Synonyms and keywords: Bitemporal hemianopsia

Overview

Bitemporal hemianopia is a specific type of visual disturbance in which sight in the outer half of the visual field of each eye is lost. As a result, the patient retains central vision but loses sight at the edges of his or her vision. This is not always obvious to him or her, even when the damage is quite severe on objective testing, because one tends to focus attention more on objects in the centre of the visual field.

Hemianopia signifies a loss of half of the visual field, and bitemporal denotes the two lateral, or temporal, sides of the head. By contrast, homonymous hemianopia signifies that the same half of each visual field is lost, ie all vision on the left, or on the right, of the midline. Such a pattern of visual loss is caused by damage to the more distal part of the optic radiation, most commonly by a stroke.
Template:Eye-stub

Etymology

"Bitemporal hemianopia" can be broken down as follows:

  • bi-: involves both left and right visual fields
  • temporal: involves the temporal visual field
  • hemi-: involves half of each visual field
  • anosia: blindness (formed by a(n) no + opsis vision + ia)

Pathophysiology

Hemianopia results from lesion of optic chiasm. This is the area where optic nerves from right cross over to the left and vice versa. Visual information from the temporal visual field falls on the nasal retina and information from nasal field falls on temporal retina. At optic chiasm nasal fibers of retina cross over to other side and carries information to higher centers.

So, when there is a lesion of optic chiasm the nasal fibers of both the retina are affected leading to loss of information from both the temporal fields.

Differential Diagnosis

Common causes

Causes based on organ system

Cardiovascular No underlying causes
Chemical / poisoning No underlying causes
Dermatologic Dermatochalasis
Drug Side Effect Chloroquine retinopathy
Ear Nose Throat No underlying causes
Endocrine Pituatary macroadenoma, Prolactinoma
Environmental No underlying causes
Gastroenterologic No underlying causes
Genetic No underlying causes
Hematologic No underlying causes
Iatrogenic No underlying causes
Infectious Disease No underlying causes
Musculoskeletal / Ortho No underlying causes
Neurologic Chloroquine retinopathy, Pituitary macroadenoma, Prolactinoma, Craniopharyngioma, Aneurysm of anterior communicating artery, Intracranial vascular loop, Meningioma, Enlarged third ventricle, Glioma of third ventricle, Chronic chiasmal arachnoiditis, Suprasellar tumors, Adamantinoma of sella turcica, Optic neuropathy, Optic chiasmal syndrome, Obstructive hydrocephalus, Traumatic chiasmal syndrome
Nutritional / Metabolic No underlying causes
Obstetric/Gynecologic Hypophyseal hypertrophy in pregnancy
Oncologic Adamantinoma of sella turcica, Craniopharyngioma, Glioma of third ventricle, Pituitary macroadenoma, Prolactinoma, Meningioma, Suprasellar tumors
Opthalmologic Dermatochalasis, Optic neuropathy, Optic chiasmal syndrome, Bilateral blepharoptosis, Traumatic chiasmal syndrome
Overdose / Toxicity No underlying causes
Psychiatric No underlying causes
Pulmonary No underlying causes
Renal / Electrolyte No underlying causes
Rheum / Immune / Allergy No underlying causes
Sexual No underlying causes
Trauma Traumatic chiasmal syndrome
Urologic No underlying causes
Dental No underlying causes
Miscellaneous No underlying causes

Causes in Alphabetical order

See also

References


Template:WH Template:WS