hemianopia

DEFINITION of hemianopia

Hemianopia (also spelled hemianopsia) is a visual field defect in which vision is absent or significantly impaired in one half of the visual field. It arises from damage anywhere along the visual pathway — from the optic chiasm posteriorly through the optic tracts, lateral geniculate nucleus, optic radiations, and visual cortex (occipital lobe). The pattern of field loss depends on the lesion location and is a critical localizing sign in neurology and ophthalmology. The most clinically significant distinction is between homonymous hemianopia (same-side field loss in both eyes, indicating a post-chiasmal retrochiasmatic lesion — most often stroke) and bitemporal hemianopia (outer field loss in both eyes, the hallmark of a chiasmal lesion such as a pituitary tumor). Hemianopia is a common and often permanent sequela of stroke, particularly involving the posterior cerebral artery (PCA) and the occipital lobe. It significantly impacts activities of daily living including reading, driving, and navigation.

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ETYMOLOGY of hemianopia

greek

Component	Origin	Meaning
hemi-	Greek hēmi- (ἡμι-)	Half
-an-	Greek an- (ἀν-)	Without, absence of
-opia	Greek ōps / opsis (ὄψ / ὄψις)	Vision, sight, eye

Literally: “without vision in half” — describing the loss of half the visual field.

-opsia variant (hemianopsia): from Greek opsis (sight) — both spellings are correct and used interchangeably in clinical practice.

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🔀 ALIASES / ALTERNATE TERMS

Spelling Variants:

• Hemianopsia (equally accepted; older spelling)
• Hemi-field visual loss

By Pattern / Type:

• Homonymous hemianopia — loss of the same half-field in both eyes (e.g., right homonymous hemianopia = loss of right visual field in both eyes); post-chiasmal lesion
• Bitemporal hemianopia — loss of both temporal (outer) fields; chiasmal lesion (classic for pituitary adenoma)
• Binasal hemianopia — loss of both nasal (inner) fields; rare; suggests bilateral lateral chiasmal compression
• Congruous hemianopia — field defects are identical in both eyes; suggests occipital cortex lesion
• Incongruous hemianopia — asymmetric defects; suggests optic tract or radiation lesion
• Quadrantanopia / Quadrantanopsia — loss of one quarter of the visual field (superior or inferior)
• Superior quadrantanopia — “pie in the sky” defect; temporal lobe lesion (Meyer’s loop)
• Inferior quadrantanopia — “pie on the floor” defect; parietal lobe lesion
• Macular sparing hemianopia — central vision preserved despite hemianopia; classic of PCA stroke with dual macular blood supply
• Cortical blindness — bilateral occipital lobe involvement; complete loss of visual cortex function

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🔗 RELATED TERMS

• Visual pathway — optic nerve → optic chiasm → optic tract → lateral geniculate nucleus (LGN) → optic radiations → visual cortex (V1, occipital lobe)
• Optic chiasm — where nasal fibers cross; lesion here = bitemporal hemianopia
• Meyer’s loop — inferior optic radiation fibers through temporal lobe; lesion = superior quadrantanopia
• Posterior cerebral artery (PCA) — most common vascular cause of homonymous hemianopia
• Pituitary adenoma — most common cause of bitemporal hemianopia
• Occipital lobe — primary visual cortex; infarction → homonymous hemianopia with macular sparing
• Visual neglect / Hemispatial neglect — distinct from hemianopia; may coexist post-stroke
• Confrontation visual field testing — bedside screening method
• Humphrey visual field (HVF) / Goldmann perimetry — formal visual field testing
• MRI brain — primary imaging for lesion localization
• Optic neuritis — inflammation of optic nerve; can cause scotoma but typically not hemianopia
• Stroke / TIA — leading cause of acquired homonymous hemianopia
• Prismatic lenses / Visual rehabilitation — treatment approaches
• Anton syndrome — cortical blindness with anosognosia (patient denies blindness)
• Riddoch phenomenon — ability to detect moving but not static objects in hemianopic field

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CODING CORNER

### 🏥 ICD-10-CM CODES

Visual Field Defects — Primary Codes (Category H53.4x)

Homonymous hemianopia maps to H53.46x (Homonymous bilateral field defects); bitemporal/heteronymous maps to H53.47.

Code	Description
H53.40	Unspecified visual field defects
H53.461	Homonymous bilateral field defects, right side (right homonymous hemianopia)
H53.462	Homonymous bilateral field defects, left side (left homonymous hemianopia)
H53.469	Homonymous bilateral field defects, unspecified side
H53.47	Heteronymous bilateral field defects (includes bitemporal & binasal hemianopia)
H53.451	Other localized visual field defect, right eye (quadrantanopia, scotoma)
H53.452	Other localized visual field defect, left eye
H53.453	Other localized visual field defect, bilateral
H53.459	Other localized visual field defect, unspecified eye
H53.481	Generalized contraction of visual field, right eye
H53.482	Generalized contraction of visual field, left eye
H53.483	Generalized contraction of visual field, bilateral

Cortical Visual Pathway Disorders (Category H47.6x)

Code	Description
H47.611	Cortical blindness, right side of brain
H47.612	Cortical blindness, left side of brain
H47.619	Cortical blindness, unspecified side of brain
H47.641	Disorders of visual cortex due to vascular disorders, right side of brain
H47.642	Disorders of visual cortex due to vascular disorders, left side of brain
H47.649	Disorders of visual cortex due to vascular disorders, unspecified side
H47.631	Disorders of visual cortex due to neoplasm, right side of brain
H47.632	Disorders of visual cortex due to neoplasm, left side of brain

Sequelae of Cerebrovascular Disease (Category I69)

Code	Description
I69.398	Other sequelae of cerebral infarction (use when hemianopia is documented as post-stroke sequela)
I69.898	Other sequelae of other cerebrovascular disease
I69.998	Other sequelae following unspecified cerebrovascular disease

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🔧 COMMON CPT CODES (Hemianopia-Related Evaluation & Management)

Visual Field Testing

CPT Code	Description
92081	Visual field examination, unilateral or bilateral, with interpretation and report; limited examination (e.g., tangent screen, Autoplot, arc perimeter, or single stimulus level automated test)
92082	Visual field examination; intermediate examination (e.g., Goldmann perimeter with multiple isopters, or automated suprathreshold testing)
92083	Visual field examination; extended examination (e.g., Goldmann visual fields with at least 3 isopters, or full threshold automated testing — Humphrey 24-2 or 30-2)

Neuroimaging

CPT Code	Description
70553	MRI brain with and without contrast (primary imaging for occipital/retrochiasmal lesions)
70551	MRI brain without contrast
70552	MRI brain with contrast
70544	MRA brain without contrast
70496	CT angiography, head

Ophthalmologic Evaluation

CPT Code	Description
92004	Ophthalmological services, new patient, comprehensive
92014	Ophthalmological services, established patient, comprehensive
92132	Scanning computerized ophthalmic diagnostic imaging (anterior segment)
92133	Scanning computerized ophthalmic diagnostic imaging, optic nerve
92134	Scanning computerized ophthalmic diagnostic imaging, retina

Neuro-Ophthalmology / Rehabilitation

CPT Code	Description
92060	Sensorimotor examination with multiple fields of fixation
97755	Assistive technology assessment (for visual rehabilitation/AAC devices)

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⚠️ Coding Note: Hemianopia does not have its own dedicated ICD-10-CM code by name — it maps primarily to H53.461 or H53.462 (homonymous bilateral field defects, right or left side) for the most common clinical type. Laterality in H53.46X refers to the side of the field loss, not the eye. When hemianopia is documented as a sequela of stroke, code both the I69.X98 sequela code AND the appropriate H53.46X- visual field code together — they are not mutually exclusive and together provide the most complete clinical picture. For pituitary-related bitemporal hemianopia, use H53.47 (heteronymous bilateral field defects) paired with the appropriate neoplasm code. As an ophthalmology coder, note that Humphrey visual field testing (92083 is the standard of care for documenting and following hemianopia and is separately reportable during a comprehensive eye exam.

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DERIVATIONS of hemianopia

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Query functionality

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Med roots Appendix A Prefixes Appendix B Combining Forms Appendix C Suffixes Appendix D Suffix forms