Prisms or "field expanders" that bend light have been prescribed for decades in patients with hemianopsia. Higher power Fresnel ("stick-on") prisms are commonly employed because they are thin and light weight, and can be cut and placed in different positions on a spectacle lens.

Peripheral prism spectacles expand the visual field of patients with hemifield visual defects and have the potential to improve visual function and mobility. Prism spectacles incorporate higher power prisms, with variable shapes and designs. The Gottlieb button prism, and the Peli superior and inferior horizontal bands are some proprietary examples of prism glasses. These high power prisms "create" artificial peripheral vision into the non-blind field for obstacle avoidance and motion detection.

Treatment of strabismic or anisometropic amblyopia consists of correcting the optical deficit (wearing the necessary spectacle prescription) and often forcing use of the amblyopic eye, by patching the good eye, or instilling topical atropine in the good eye, or both.

Concerning patching versus atropine, a drawback is seen in using atropine; the drops can have a side effect of creating nodules in the eye which a correctional ointment can counteract. One should also be wary of overpatching or overpenalizing the good eye when treating amblyopia, as this can create so-called "reverse amblyopia". Eye patching is usually done on a part-time schedule of about 4–6 hours a day. Treatment is continued as long as vision improves. It is not worthwhile continuing to patch for more than 6 months if no improvement continues. Treatment of individuals age 9 through to adulthood is possible through applied perceptual learning.

Deprivation amblyopia is treated by removing the opacity as soon as possible followed by patching or penalizing the good eye to encourage the use of the amblyopic eye. The earlier the treatment is initiated, the easier and faster the treatment is and the less psychologically damaging. Also, the chance of achieving 20/20 vision is greater if treatment is initiated early.

One of the German public health insurance providers, Barmer, has changed its policy to cover, as of 1 April 2014, the costs for an app for amblyopic children whose condition has so far not improved through patching. The app offers dedicated eye exercises which the patient performs while wearing an eyepatch.

Although the best outcome is achieved if treatment is started before age 8, children older than age 12 and some adults can show improvement in the affected eye. Children from 9 to 11 who wore an eye patch and performed near-point activities (vision therapy) were four times as likely to show a two-line improvement on a standard 11-line eye chart than children with amblyopia who did not receive treatment. Adolescents aged 13 to 17 showed improvement, as well, albeit to a lesser degree than younger children. Whether such improvements are only temporary, however, is uncertain, particularly if treatment is discontinued.

Tentative evidence shows that perceptual training may be beneficial in adults.

Virtual-reality computer games where each eye receives different signals of the virtual world that the player's brain must combine to successfully play the game have shown some promise in improving both monocularity in the affected eye, as well as binocularity.

Binasal hemianopsia (or binasal hemianopia) is the medical description of a type of partial blindness where vision is missing in the inner half of both the right and left visual field. It is associated with certain lesions of the eye and of the central nervous system, such as congenital hydrocephalus.

An anopsia or anopia is a defect in the visual field. If the defect is only partial, then the portion of the field with the defect can be used to isolate the underlying cause.

Types of partial anopsia:

- Hemianopsia

- Homonymous hemianopsia

- Heteronymous hemianopsia

- Binasal hemianopsia

- Bitemporal hemianopsia

- Superior hemianopia

- Inferior hemianopia

- Quadrantanopia

The term "anopsia" comes from the Ancient Greek ἀν- ("an-"), "un-" and ὄψις ("opsis") "sight".

When the pathology involves both eyes, it is either homonymous or Heteronymous.

Hemianopsia or hemianopia is a visual field loss on the left or right side of the vertical midline. It can affect one eye but usually affects both eyes. Homonymous hemianopsia, or homonymous hemianopia, is hemianopic visual field loss on the same side of both eyes. Homonymous hemianopsia occurs because the right half of the brain has visual pathways for the left hemifield of both eyes, and the left half of the brain has visual pathways for the right hemifield of both eyes. When one of these pathways is damaged, the corresponding visual field is lost.

Hemianopsia, or hemianopia, is a decreased vision or blindness (anopsia) in half the visual field, usually on one side of the vertical midline. The most common causes of this damage are stroke, brain tumor, and trauma.

This article deals only with permanent hemianopsia, and not with transitory or temporary hemianopsia, as identified by William Wollaston PRS in 1824. Temporary hemianopsia can occur in the aura phase of migraine.

Bitemporal hemianopsia, also known as bitemporal heteronymous hemianopsia or bitemporal hemianopia, is the medical description of a type of partial blindness where vision is missing in the outer half of both the right and left visual field. It is usually associated with lesions of the optic chiasm, the area where the optic nerves from the right and left eyes cross near the pituitary gland.

In binasal hemianopsia, vision is missing in the inner (nasal or medial) half of both the right and left visual fields. Information from the nasal visual field falls on the temporal (lateral) retina. Those lateral retinal nerve fibers do not cross in the optic chiasm. Calcification of the internal carotid arteries can impinge the uncrossed, lateral retinal fibers leading to loss of vision in the nasal field.

Note: Clinical testing of visual fields (by confrontation) can produce a false positive result (particularly in inferior nasal quadrants).

In bitemporal hemianopsia vision is missing in the outer (temporal or lateral) half of both the right and left visual fields. Information from the temporal visual field falls on the nasal (medial) retina. The nasal retina is responsible for carrying the information along the optic nerve, and crosses to the other side at the optic chiasm. When there is compression at optic chiasm the visual impulse from both nasal retina are affected, leading to inability to view the temporal, or peripheral, vision. This phenomenon is known as bitemporal hemianopsia. Knowing the neurocircuitry of visual signal flow through the optic tract is very important in understanding bitemporal hemianopsia.

Bitemporal hemianopsia most commonly occurs as a result of tumors located at the mid-optic chiasm. Since the adjacent structure is the pituitary gland, some common tumors causing compression are pituitary adenomas and craniopharyngiomas. Also another relatively common neoplastic cause is meningiomas. A cause of vascular origin is an aneurysm of the anterior communicating artery which arise superior to the chiasm, enlarge, and compress it from above.