During evaluation of ectropion, the 'snap-back' test is performed by pulling the lower eyelid downward and releasing. In involutional ectropion, which finding on snap-back test and distraction test indicates lateral canthal tendon laxity?

• A Snap-back > 3 seconds, distraction < 6 mm
• B Snap-back ≤ 1 second, distraction > 10 mm
• C Snap-back > 3 seconds, distraction > 8 mm ✓
• D Snap-back normal, distraction < 4 mm

Explanation

A snap-back test that takes more than 2-3 seconds for the lid to return to its normal position (without a blink) indicates poor lid tone from horizontal laxity. A distraction test > 8 mm (displacing the lower lid from the globe) confirms significant horizontal laxity of the canthal tendons and lid. Both findings together indicate the need for horizontal lid tightening as part of ectropion correction.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.