Homonymous hemianopia: challenges and solutions

Abstract

Stroke is the most common cause of homonymous hemianopia (HH) in adults, followed by trauma and tumors. Associated signs and symptoms, as well as visual field characteristics such as location and congruity, can help determine the location of the causative brain lesion. HH can have a significant effect on quality of life, including problems with driving, reading, or navigation. This can result in decreased independence, inability to enjoy leisure activities, and injuries. Understanding these restrictions, as well as the management options, can aid in making the best use of remaining vision. Treatment options include prismatic correction to expand the remaining visual field, compensatory training to improve visual search abilities, and vision restoration therapy to improve the vision itself. Spontaneous recovery can occur within the first months. However, because spontaneous recovery does not always occur, methods of reducing visual disability play an important role in the rehabilitation of patients with HH.

Keywords: hemianopia; homonymous hemianopia; perimetry; visual field defects; visual training.

Figure 1

Examples of homonymous hemianopia with corresponding neuroimaging. Notes: (A) Complete right homonymous hemianopia following a left occipital lobe stroke (axial T1 magnetic resonance image [MRI] with contrast). (B) Left congruous homonymous hemianopia due to right occipital lobe encephalomalacia (axial T2 MRI). The patient also has a large Virchow–Robin space along the right optic tract, but it was felt the encephalomalacia was the more likely cause of visual field loss. (C) Left incongruous homonymous hemianopia due to right parietal lobe arteriovenous malformation (axial T2 MRI). (D) Right superior quadrantanopia following a stroke involving the left lingual gyrus and a right homonymous hemianopia involving the lower quadrant after a separate stoke involving the anterior portion of the left cuneus gyrus (sagittal T1 MRI on left and axial T2 MRI on right; the dotted line on the left image indicates the level of the axial scan). (E) Left incongruous homonymous hemianopia with macular sparing due to hydrocephalus and subsequent shunt (axial T1 MRI).

Figure 2

Band atrophy. Note the pallor of the nasal and temporal portions of the optic disc.

Figure 3

Example of how an ipsilateral exotropia can extend the usable visual field. Notes: A 67-year-old male presented with complete right homonymous hemianopia following a stroke involving the occipital lobe. He had a long-standing 40 prism diopter right exotropia without amblyopia. Visual acuities were 20/20 in each eye. Monocular testing demonstrated a complete right homonymous hemianopia (A). With binocular visual field testing (B), the patient was able to see an additional 30° on the side of the hemianopia.