Lesions implicating the cortical centre for sight in the occipital lobe give rise to hemianopia -- that is, loss of sight in the lateral halves of the fields of vision of both eyes -- colour-blindness, subjective sensations of light and colour, and other eye symptoms. ❋ Alexander Miles (1893)
The optic tract, which crosses the crus, may also be affected, and hemianopia result. ❋ Alexander Miles (1893)
When the posterior part of the capsule is involved, there are, in addition, hemianæsthesia and hemianopia, and sometimes disturbances of hearing, smell, and taste. ❋ Alexander Miles (1893)
People with hemianopia often do not know what they can't see and frequently bump into and trip over objects while walking. ❋ Unknown (2009)
Schepens Eye Research Institute scientists have found that -- when tested in a driving simulator -- patients with hemianopia (blindness in one half of the visual field in both eyes) have significantly more difficulty detecting pedestrians (on their blind side) than normally sighted people. ❋ Unknown (2009)
Peli and his research team compared 12 subjects with hemianopia to 12 visually normal people, matched by age, sex, and years of driving experience. ❋ Unknown (2009)
Investigative Ophthalmology and Visual Science, fly in the face of some recent on-road studies that have found most people with hemianopia safe to drive. ❋ Unknown (2009)
They also found a large variability in blind-side detection rates among the individuals with hemianopia (from 6% to 100%) with the lower rates found among the older subjects. ❋ Unknown (2009)
The scientists found that drivers with hemianopia had much lower detection rates on their blind side than normally sighted subjects (or their own seeing side), detecting on average only about 45% of pedestrian figures. ❋ Unknown (2009)
More than a million people suffer from hemianopia, a condition in which one half of the visual field in both eyes is blinded, usually the result of a stroke or head injury. ❋ Unknown (2009)
She and Peli believe the Schepens study, because it was conducted in the safety of a driving simulator over a longer period of time and "miles" than a typical "on-road" study, provides new insights into detection failures of drivers with hemianopia. ❋ Unknown (2009)
People with hemianopia have difficulty detecting pedestrians, study cautions against allowing them to drive ❋ Unknown (2009)
The next step for the team is to determine whether an optical aid that expands the visual field - peripheral prism (expansion prism EP) glasses - might be a useful device for drivers with hemianopia. ❋ Unknown (2009)
Although overall most subjects with hemianopia had detection rates that seem incompatible with safe driving, Bowers cautions that "the relationship of our simulator detection performance measures to on-road performance has yet to be established, another reason to treat each person with hemianopia individually as they seek approval to get back on the road." ❋ Unknown (2009)
Specifically, they plan to conduct another driving simulator study to investigate whether drivers with hemianopia have better detection rates for pedestrians on the blind side when using the glasses than when driving without them. ❋ Unknown (2009)
In at least 22 states and many other countries, people with hemianopia are prohibited from driving because they do not meet the visual field requirements for licensure. ❋ Unknown (2009)
These results, published in the November 2009 issue of Investigative Ophthalmology and Visual Science, fly in the face of some recent on-road studies that have found most people with hemianopia safe to drive. ❋ Unknown (2009)
