Secondary Intention Healing — SCE Dermatology MCQ

Correct answer: E — 4-8 weeks — nasal wounds heal by secondary intention with acceptable cosmetic results for concave surfaces (medial canthus, alar crease, nasal sidewall) but convex surfaces heal less predictably

The correct answer is E, 4-8 weeks, because nasal wounds left to heal by secondary intention after Mohs surgery typically re-epithelialise and contract over this timeframe when the defect lies on a concave surface such as the medial canthus, alar crease or nasal sidewall. Concave anatomical sites allow wound contraction to pull tissue inward, restoring normal contour and yielding an acceptable, often excellent, cosmetic result within this period. Convex sites (nasal tip, dorsum, ala rim) lack this favourable geometry, so contraction distorts the free margins and produces a less predictable, sometimes disfiguring, scar, which is why site selection for secondary intention is critical in nasal reconstruction. UK dermatological surgical wound care guidance for skin surgery consistently quotes several weeks of regular dressing changes for open wounds of this size and depth, consistent with the 4-8 week figure. Why the other options are wrong: A. 1 day: This is far too short for any re-epithelialisation or wound contraction to occur; even simple sutured wounds need days before the epidermis bridges the gap, let alone an open nasal defect. C. 6 months: This grossly overestimates typical healing time for a nasal wound of this type; six months would suggest a complicated course such as infection, poor vascular supply or a very large, deep defect rather than routine secondary intention healing. D. 1 week: One week allows only initial granulation tissue formation, not adequate re-epithelialisation or contraction to close a nasal Mohs defect. B. 12 months: This timeframe is wildly excessive and would indicate a non-healing or chronic wound, which is not the expected course for standard secondary intention healing on the nose. Key point: Nasal defects heal well by secondary intention within 4-8 weeks only on concave surfaces (medial canthus, alar crease, nasal sidewall), whereas convex surfaces heal less predictably and often need flap or graft reconstruction instead.

Reference: NHS Lothian, Wound healing by secondary intention after skin surgery, patient information leaflet V3.0, 2023 (https://policyonline.nhslothian.scot/wp-content/uploads/2023/03/Wound_healing_by_secondary_intention_after_skin_surgery.pdf)