A 68-year-old man with a 3-day history of progressive visual loss in the right eye, initially worse on waking. The right optic disc appears swollen with splinter hemorrhages. ESR is 85 mm/hr. CRP is elevated. Temporal artery biopsy is planned. Before the result returns, the MOST critical immediate management step is:

• A Start oral prednisolone 1 mg/kg and await biopsy before increasing dose
• B Aspirin 300 mg immediately and refer for urgent temporal artery biopsy
• C Await biopsy result before starting any treatment to avoid false-negative biopsy
• D IV methylprednisolone 1g/day for 3 days to prevent contralateral eye involvement ✓

Explanation

Giant cell arteritis (GCA/temporal arteritis) with visual involvement (anterior ischemic optic neuropathy pattern) requires IMMEDIATE high-dose IV methylprednisolone (1 g/day × 3 days) to protect the contralateral eye, which has up to 25-50% risk of involvement within days if untreated. Treatment should NOT be delayed for biopsy — biopsy remains positive for up to 2 weeks after starting steroids due to persistence of histological changes (granulomas). The 'skip lesions' make bilateral biopsy preferable. This is the most sight-threatening emergency in neuro-ophthalmology.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.