A 70-year-old man with herpes zoster ophthalmicus involving the nasociliary nerve develops a branching corneal lesion 5 days after the vesicular rash. On slit-lamp examination, the lesion is elevated, plaque-like, and stains minimally with fluorescein. Which morphological feature most reliably distinguishes this pseudodendrite from a true dendrite of herpes simplex keratitis?
- A Branching pattern
- B Absence of terminal end bulbs ✓
- C Minimal fluorescein staining
- D Elevated, plaque-like morphology
Correct answer: B. Absence of terminal end bulbs
Explanation
Terminal end bulbs at the ends of branches are the hallmark of true herpes simplex dendrites and are absent in herpes zoster pseudodendrites. Both lesions can show branching patterns. Minimal staining and elevated morphology are supportive features but not pathognomonic, as early HSV dendrites can also stain poorly. The absence of terminal bulbs is the single most reliable distinguishing morphological feature.
Reference: AAO Basic Course of Ophthalmology (BCSC Section 8: External Disease and Cornea), 2023-2024 ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.