Optic Neuritis: NEET PG Focus
Neuro-Ophthalmology: Demyelinating Optic Neuropathy
1. Pathophysiology & NEET Associations
Optic neuritis is an inflammatory, demyelinating condition. It is strongly linked to Multiple Sclerosis (MS), particularly in females aged 15–45. A key NEET pearl is that optic neuritis is often the first presenting clinical sign of MS.
2. Clinical Presentation
| Clinical Feature | High-Yield Description |
|---|---|
| Vision Loss | Acute, unilateral, central scotoma. |
| Pain | Pathognomonic: Pain worse with eye movement. |
| Pupillary Sign | RAPD is always present in unilateral cases. |
| Color Vision | Dyschromatopsia (classic red desaturation). |
3. Key Management Pearls
- ONTT (Optic Neuritis Treatment Trial): Established that IV methylprednisolone speeds recovery, but oral prednisone is contraindicated as it increases recurrence risk.
- Imaging: MRI Brain with gadolinium contrast is the gold standard to check for demyelinating plaques (MS risk stratification).
- Disc Appearance: Anterior (papillitis) vs. Retrobulbar (normal disc). Retrobulbar is more common in adults; papilledema is more common in children.
- Uhthoff’s Phenomenon: Worsening of vision with heat or exercise (classic MS-related clinical sign).