OP2.5 | Cavernous Sinus Thrombosis: Ocular Features and Management — Summary & Reflection

KEY TAKEAWAYS

Cavernous sinus thrombosis is a life-threatening (20–30% mortality) complication of orbital, facial, dental, and sinus infections. The cavernous sinus contains CN III, IV, V1, V2 in its lateral wall and CN VI and the ICA in its lumen — CN VI is affected first (lateral rectus palsy, esotropia) because it runs in the lumen. Bilateral proptosis and ophthalmoplegia (pathognomonic) occur because the two cavernous sinuses are connected via intercavernous sinuses. Infection spreads via valveless ophthalmic veins from the orbit, or via the facial vein from the 'danger triangle.' Diagnosis is confirmed by MRI (cavernous sinus filling defect). Management: IV ceftriaxone + metronidazole (± vancomycin for MRSA), anticoagulation (controversial), source control. Complications include permanent CN palsies, blindness, stroke, meningitis, and death.

REFLECT

The patient in the hook scenario had a facial boil that he squeezed — and two weeks later he was in intensive care with bilateral ophthalmoplegia and neck stiffness. Reflect on how you would counsel a patient you see in the OPD who has a boil on the upper lip: what would you specifically tell them NOT to do, and why? In a resource-limited setting without 24-hour MRI, what clinical features would you use to make the diagnosis and begin treatment? How do the principles of antibiotic stewardship conflict with the need for broad-spectrum immediate coverage in a condition like CST?