Ocular Flashcards
Miosis (pupillary constriction) occurs via what muscle and what limb of the NS?
Pupillary sphinctor muslce of the iris via PNS (M3)
Mydriasis (pupillary dilation) occurs via what muscle and what limb of the NS?
Radial dilator muscle of the iris via SNS (alpha)
Accomodation occurs via what muscle and what limb of the NS?
Ciliary muscle via PNS (M3), specifically, the circular fibers
Secretion of aqueous humor occurs via what structure and what limb of the NS?
Ciliary body epithelium via SNS (beta)
In the eye, muscarinic receptors (PNS) are found where? What about nicotinic receptors (PNS) ?
Muscarinic: Ciliary body, Iris. Nicotinic: Extraocular muscles
In the eye, what is the major endogenous NT of the PNS? What is the major receptor? What does it do?
Ach. Muscarinic. Constrict pupil (pupillary sphinctor m. of the iris + circular fibers of the ciliary muscle), Place tension on trabecular meshwork (longitudinal fibers of ciliary muscle)
Ach class?
Direct muscarinic agonist
Pilocarpine class?
Direct muscarinic agonist
Carbachol class?
Direct muscarinic agonist
Methacholine class?
Direct muscarinic agonist
Direct muscarinic agonists used in ocular treatment?
Acetylcholine, Pilocarpine, Carbachol, Methacholine
Major effects and uses of muscarinic agonists in the eye?
Pupillary constriction, Increased aqueous outflow. Used for cataract surgery and treatment of glaucoma.
Ach for?
Pupillary constriction – used in cataract surgery
Pilocarpine for?
Pupillary constriction, increased aqueous outflow – tx of glaucoma
Carbachol for?
Pupillary constriction, increased aqueous outflow – tx of glaucoma
Side effects of direct muscarinic agonists?
Lacrimation, sweating, bronchospasm, salivation, N/V/D, abdominal pain, tenesmus
Muscarinic antagonists used in ocular treatment?
Atropine, Scopolamine, Homatropine, Cyclopentolate, Tropicamide
Major effects and uses of muscarinic antagonists in the eye?
Pupillary dilation, Paralysis of ciliary body. Used for cycloplegia for eye exams and to improve comfort during active eye inflammation (for example, uveitis)
Atropine class?
Antimuscarinic
Scopolamine class?
Antimuscarinic
Homatropine class?
Antimuscarinic
Cyclopenolate class?
Antimuscarinic
Tropicamide class?
Antimuscarinic
Atropine for?
Pupillary dilation, paralysis of ciliary body – Improve comfort during active eye inflammation
Atropine timing?
VERY long acting: Maximal strength in 30-40 minutes, with recovery lasting 7-10 days
Scopolamine for?
Pupillary dilation, paralysis of ciliary body – Improve comfort during active eye inflammation
Homatropine for?
Pupillary dilation, paralysis of ciliary body – Cycloplegia for eye exams, Improve comfort during active eye inflammation
Cyclopentolate for?
Pupillary dilation, paralysis of ciliary body – Cycloplegia for eye exams, Improve comfort during active eye inflammation
Tropicamide for?
Pupillary dilation, paralysis of ciliary body – Most commonly used for eye exams
Tropicamide timing?
Maximal strength in 20-40 minutes, with recovery lasting less than 1/4 of a day
Edrophonium class?
Acetylcholinesterase Inhibitor: Indirect nicotinic agonist
Edrophonium for?
Differentiate myasthenia gravis from an acute acetyl choline crisis
Side effects of antimuscarinics?
Anhidrosis, urinary retention, ataxia, nystagmus, photophobia, mental confusion, hallucination, violent/aggressive behavior, insomnia
In the eye, what is the major endogenous NT of the SNS? What is the major receptor? What does it do?
NE. Alpha & Beta. Dilate pupil (radial dilator m. of the iris), Aqueous production (ciliary body epithelium), Increase outflow of aqueous (trabecular meshwork), lift eyelid (superior palpebral m.), dilate blood muscles (smooth muscle of ocular blood vessels)
Phenylephrine class?
Direct alpha1 agonist
Phenylephrine for?
Pupillary dilation – eye exam, cataract surgery
Epinephrine class?
Direct adrenergic agonist
Epinephrine for?
Dilation of episcleral vessels – Increased aqueous outflow
Dipvalyl class?
Direct adrenergic agonist (prodrug of epinephrine)