**Question:** Ocular symptom not seen in Herpes zoster is-

A. Conjunctivitis
B. Corneal ulcer
C. Uveitis
D. Retinal necrosis

**Correct Answer:**

**Core Concept:** Herpes zoster is a viral infection caused by the reactivation of the varicella-zoster virus (VZV), which is the same virus responsible for causing chickenpox in childhood. After primary infection, VZV remains latent in the dorsal root ganglia and can be reactivated later in life, leading to herpes zoster.

**Why the Correct Answer is Right:** The correct answer is **D** - Retinal necrosis - as it is a severe complication of herpes zoster that occurs in a small percentage of cases (around 1%). Retinal necrosis refers to the necrosis (cell death) of retinal tissue, which is not a typical ocular manifestation of herpes zoster.

**Why Each Wrong Option is Incorrect:**

**A** - Conjunctivitis: Herpes zoster can cause ocular manifestations like conjunctivitis, which is an inflammation of the conjunctiva. However, this is not the correct answer because it is a possible manifestation of the disease, not absent.

**B** - Corneal ulcer: Although herpes zoster can lead to ocular manifestations, corneal ulcer is not typically seen in this condition. The correct answer is retinal necrosis instead.

**C** - Uveitis: Herpes zoster can cause uveitis, which is inflammation of the uvea (the middle layer of the eye) that may lead to complications like retinal necrosis. However, this is not the correct answer because uveitis is a possible manifestation of the disease, not absent.

**Clinical Pearl:**

Understanding the various manifestations of herpes zoster is essential for clinical practice, as these manifestations can lead to severe complications like retinal necrosis. Ocular herpes zoster can present with various symptoms like conjunctivitis, uveitis, keratitis, and retinitis. Early recognition and prompt treatment are crucial to prevent severe complications and protect visual function.

Remember, herpes zoster ophthalmicus is a clinical entity characterized by the involvement of the ophthalmic branch of the trigeminal nerve, leading to ocular manifestations of herpes zoster. The correct answer, retinal necrosis, is a severe complication that occurs in a small number of cases and highlights the importance of recognizing and treating ocular herpes zoster promptly to prevent severe visual complications.