Professional and Linguistic Assessments Board (PLAB) Practice Exam

What condition is characterized by sudden painless loss of vision in one eye lasting more than 10 minutes?

1. Retinal detachment

2. Cataract

3. Central retinal artery occlusion

4. Vitreous hemorrhage

The correct answer is: Central retinal artery occlusion

The condition characterized by sudden painless loss of vision in one eye lasting more than 10 minutes is central retinal artery occlusion. This condition occurs when the blood flow through the central retinal artery, which supplies blood to the retina, is obstructed. The interruption in blood flow leads to a rapid loss of vision that is often described as sudden and can be associated with a "whitening" of the vision in the affected eye. In central retinal artery occlusion, vision loss may last longer than 10 minutes, and it typically does not present with pain. The affected individual may experience a complete loss of vision or a significant reduction in visual acuity, and further symptoms can vary based on the extent of the occlusion. Understanding the characteristics of this condition is crucial, as rapid diagnosis and treatment can significantly impact the outcome. Conversely, other options involve different clinical presentations; for example, retinal detachment may include symptoms like flashes of light and floaters, while cataracts typically cause gradual vision loss and may be associated with blurred or cloudy vision rather than a sudden loss. Vitreous hemorrhage generally presents with floaters or shadows and can cause sudden vision changes but typically not for prolonged durations as seen with central retinal artery occlusion.