Which ocular condition is NOT worse in the morning?

• A. Thyroid Eye Disease
• B. Exposure Keratopathy
• C. Recurrent Corneal Erosion
• D. Myasthenia Gravis

Answer: (D)

Ocular symptoms that come and go with use and rest explain why this particular condition is not worse in the morning. The lying-flat overnight and reduced blinking during sleep tend to dry and expose the ocular surface, so conditions that cause surface irritation or poor lid protection—like exposure keratopathy and recurrent corneal erosion—tend to be worse upon waking. Thyroid eye disease with proptosis and lid retraction can also produce more surface exposure after a night of sleep, contributing to morning symptoms.

In contrast, myasthenia gravis shows fatigable weakness of the ocular muscles. The eyelid and extraocular muscles can appear better after a period of rest, such as overnight sleep, and symptoms often worsen with sustained use as the day progresses. Therefore, the ocular involvement in myasthenia gravis is typically not worse in the morning, aligning with a pattern of improvement with rest rather than with inactivity or exposure.