Adult-Gerontology Clinical Nurse Specialist (CNS) Practice Exam

What medical condition is characterized by the presence of halos around lights?

1. Acute angle-closure glaucoma

2. Cataracts

3. Macular degeneration

4. Diabetic retinopathy

The correct answer is: Acute angle-closure glaucoma

The presence of halos around lights is primarily associated with acute angle-closure glaucoma. This condition occurs when there is a sudden increase in intraocular pressure due to the obstruction of the drainage angle in the eye. As a result, patients may experience not only halos around lights but also other symptoms such as severe eye pain, headache, nausea, vomiting, and blurred vision. The halos are caused by the way light is refracted through the cornea when fluid accumulates behind it due to the elevated pressure. While cataracts can also cause visual disturbances, including blurriness and changes in color perception, they do not specifically lead to the perception of halos. In cataracts, the clouding of the lens affects light passage but does not typically create the same phenomenon as seen in angle-closure glaucoma. Macular degeneration and diabetic retinopathy mainly impact central vision and do not produce halos around lights. These conditions lead to different types of visual impairment, focusing more on distortion or loss of clarity rather than light distortion effects like halos. Therefore, the characteristic symptom of halos around lights distinctly points to acute angle-closure glaucoma as the medical condition being referred to in this context.