During which examination would you primarily assess visual acuity?

Visual acuity is primarily assessed during a refraction assessment. This examination focuses specifically on determining the eye's ability to perceive details, typically using an eye chart to measure how clearly a person can see at various distances. The refraction assessment involves calculating the proper lenses needed to correct any refractive errors such as myopia, hyperopia, or astigmatism, which directly relates to visual acuity.

In the context of this question, a slit-lamp examination primarily evaluates the anterior structures of the eye, such as the cornea, iris, and lens, but does not specifically measure visual acuity. A fundus examination is conducted to inspect the interior surface of the eye, including the retina and optic nerve, providing crucial information about the health of these structures but not about visual acuity. Tonometry measures intraocular pressure, which is essential for glaucoma assessment but does not involve testing how well a person can see. Thus, the refraction assessment is the examination where visual acuity is the primary focus.