[HAP-11] Special Senses (Eye & Ear) and Integumentary (Skin) Physiology & Pharmacology
HAP-11 • 1. Anatomy & PhysiologyLearning Objectives
Trace aqueous humour production (ciliary body non-pigmented epithelium via β2-adrenoceptors & carbonic anhydrase) and outflow (trabecular meshwork vs uveoscleral pathway) in Glaucoma.; Compare Open-Angle vs Acute Angle-Closure Glaucoma pharmacotherapy ([4.16] Timolol, [4.17] Latanoprost, [4.18] Acetazolamide, Pilocarpine, [3.23] Mannitol).; Map epidermal strata (basale, spinosum, granulosum, lucidum, corneum) and topical dermatological vehicles, steroid potency classes, and acne/scabies therapy.
Chapter Overview & Core Explanation
The eye maintains its spherical shape through continuous circulation of clear aqueous humour fluid; if drainage becomes blocked, intraocular pressure rises and damages the optic nerve (glaucoma). Meanwhile, the skin's outer stratum corneum acts as a brick-and-mortar lipid barrier that governs topical drug absorption.
Key Exam & Clinical Takeaways
- Prostaglandin analogues ([4.17] Latanoprost) lower IOP primarily by increasing uveoscleral outflow, whereas [4.16] Timolol and [4.18] Acetazolamide decrease aqueous humour secretion.
- Super-potent topical corticosteroids ([12.2] Clobetasol Propionate 0.05%) must NEVER be applied to the face, groin, or axillae or mixed with antifungal creams for tinea (steroid-modified tinea incognito).