Latanoprost, a prostaglandin F2α analogue used in glaucoma, lowers IOP primarily by which mechanism?
- A Increasing uveoscleral (unconventional) outflow by remodelling ciliary muscle and extracellular matrix ✓
- B Reducing aqueous humour production from the ciliary epithelium
- C Increasing trabecular (conventional) outflow by opening intratrabecular spaces
- D Reducing episcleral venous pressure
Correct answer: A. Increasing uveoscleral (unconventional) outflow by remodelling ciliary muscle and extracellular matrix
Explanation
Prostaglandin analogues (latanoprost, travoprost, bimatoprost) lower IOP by increasing uveoscleral outflow through remodelling of the extracellular matrix in the ciliary muscle and uveoscleral pathway. This is mediated by MMP upregulation. They do not significantly reduce aqueous production or trabecular outflow. Beta-blockers and carbonic anhydrase inhibitors reduce aqueous production; alpha-agonists have dual action; miotics increase trabecular outflow.
Reference: Khurana Comprehensive Ophthalmology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.