The Watzke-Allen test and the photostress recovery time are specifically used to evaluate dysfunction at which retinal level?
- A Müller cell function in Henle's layer
- B Retinal pigment epithelium (RPE) and photoreceptor outer segments ✓
- C Ganglion cell layer integrity
- D Inner nuclear layer synaptic function
Correct answer: B. Retinal pigment epithelium (RPE) and photoreceptor outer segments
Explanation
The photostress recovery time (PSRT) measures the time taken for Snellen acuity to recover after bleaching the macula with a bright light — this reflects RPE efficiency in regenerating visual pigment (rhodopsin/cone opsins) in the outer segments. A prolonged PSRT suggests macular disease at the RPE-photoreceptor interface. The Watzke-Allen test passes a slit-beam across the fovea: thinning in full-thickness macular holes causes the beam to appear 'broken', distinguishing full-thickness holes from pseudoholes or lamellar defects.
Reference: Khurana Comprehensive Ophthalmology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.