What are the features of a temporo-occipital infarct?

Features of Temporooccipital Infarction

Temporooccipital infarctions present with distinctive visual field defects, cognitive impairments, and neurological symptoms that reflect the critical role of these regions in visual processing and higher cognitive functions.

Primary Clinical Manifestations

• Visual field defects are the most common presentation, typically manifesting as homonymous hemianopsia or quadrantanopsia depending on the exact location and extent of the infarct 1, 2
• Central vision impairment may occur alongside peripheral visual field defects, affecting reading ability and fine visual discrimination 2
• Color vision disturbances (achromatopsia) can occur but are relatively rare in patient self-reports 1
• Phosphenes (visual sensations of light when none is actually entering the eye) are commonly reported and associated with lesions of the calcarine sulcus 1

Cognitive and Language Manifestations

• Reading difficulties (alexia) are frequently reported and associated with lesions of the calcarine sulcus 1
• Anomia (word-finding difficulties) is common and associated with lesions of the occipital inferior gyrus and lingual gyrus 1
• Memory deficits are frequently reported and linked to lesions affecting the occipital inferior gyrus, lingual gyrus, hippocampus, and principal white matter tracts 1
• Topographical disorientation (difficulty navigating familiar environments) may occur, particularly with right-sided lesions 3

Less Common Manifestations

• Prosopagnosia (inability to recognize faces) is rarely self-reported but may be present on formal testing 1
• Akinetopsia (inability to perceive motion) is uncommon but can occur with specific lesion locations 1
• Executive dysfunction may be present, particularly with larger infarcts 3
• Fatigue is commonly reported during recovery 3

Risk Factors for Bilateral Vision Loss

• Advanced age increases risk of developing a contralateral occipital infarction 4
• General vascular risk factors contribute to the likelihood of bilateral involvement 4
• History of previous strokes significantly increases risk of contralateral occipital infarction 4
• Sylvian border-zone extension of the initial infarct is associated with higher risk of spread to the contralateral side 4
• Lack of improvement in initial visual field defects is the strongest predictor of developing cortical blindness from a contralateral occipital infarction 4

Diagnostic Evaluation

• Rey-Osterrieth Complex Figure Test for immediate recall is effective for screening memory disorders 1
• Demtect and Lang Stereo Test are useful clinical screening tools for visual disorders 1
• MRI is superior to CT for identifying occipital infarctions, especially in the acute phase 5
• Visual field testing is essential to document the extent and pattern of visual loss 5

Management Considerations

• Monitoring for deterioration is essential, with frequent assessment of level of arousal and pupillary function 6
• Osmotic therapy may be reasonable for patients with clinical deterioration from cerebral swelling associated with the infarction 6
• Elevation of head of bed to 30° is generally recommended to reduce space-occupying effects of brain swelling 6
• Deep venous thrombosis prophylaxis with subcutaneous heparin or low-molecular-weight heparin should be initiated despite risk of hemorrhagic transformation 6
• Seizure monitoring may be warranted in patients with fluctuating consciousness, though seizures are uncommon 6

Recovery and Prognosis

• Long-term functional recovery can be remarkable in some patients, particularly younger individuals 3
• Multi-modality rehabilitation including formal therapy and self-directed activities may contribute to cognitive recovery 3
• Extended recovery time should be anticipated, with improvements potentially continuing for years after the initial event 3
• Neuroplastic brain changes can occur in areas serving similar functions to those damaged by the stroke 3

Complications and Monitoring

• Risk of bilateral occipital infarction leading to cortical blindness occurs in approximately 22.4% of patients with unilateral occipital infarction 4
• Careful follow-up and controlled medical therapy is particularly indicated in patients with risk factors for bilateral involvement 4
• Visual rehabilitation with optical systems can be successful in managing visual field loss 5