Acute angle-closure glaucoma: Difference between revisions
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== Treatment == | == Treatment == | ||
*Emergent ophthalmology consult | #*Emergent ophthalmology consult | ||
#Decrease production of aqueous humor: | |||
#'''timolol 0.5% drop''': blocks beta receptors on ciliary epithelium | #*'''timolol 0.5% drop''': blocks beta receptors on ciliary epithelium | ||
#'''apraclonidine 1% drop''': alpha-2 adrenergic receptor agonist which increases trabecular outflow | #*'''apraclonidine 1% drop''': alpha-2 adrenergic receptor agonist which increases trabecular outflow | ||
#'''acetazolamide 500mg IV or PO''': blocks productions of HCO3-, which draws Na+ into the eye; water follows by osmosis to form aqueous humour | #*'''acetazolamide 500mg IV or PO''': blocks productions of HCO3-, which draws Na+ into the eye; water follows by osmosis to form aqueous humour | ||
#Facilitate outflow of aqueous humor: | |||
#'''pilocarpine 1%–2% drop''': parasympatholytic alkaloid acts on muscarinic receptors found on iris sphincter muscle ==> causes muscle to contract ==> miosis | #*'''pilocarpine 1%–2% drop''': parasympatholytic alkaloid acts on muscarinic receptors found on iris sphincter muscle ==> causes muscle to contract ==> miosis | ||
#*In USA - green top | #**In USA - green top | ||
#*Use one drop every 15 minutes x 2 doses, then every 4 to 6 hours | #**Use one drop every 15 minutes x 2 doses, then every 4 to 6 hours | ||
#*Only effective when IOP <40 mm Hg | #**Only effective when IOP <40 mm Hg | ||
#Reduce volume of aqueous humor: | |||
#*'''[[mannitol]] 1–2gm/kg IV''': if no contraindications | |||
#Recheck IOP hourly | |||
==See Also== | ==See Also== | ||
Revision as of 20:35, 3 June 2015
Background
Pathophysiology
- Obstructed aqueous outflow tract > aqueous humor builds > increased intraocular pressure (IOP) > optic nerve damage > vision loss
- Increased posterior chamber pressure causes iris to bulge forward (iris bombé) > further obstruction of outflow tract > further increase IOP
- Acute attack is usually precipitated by pupillary dilation
Clinical Features
- Abrupt onset of severe eye pain
- Blurred vision
- Frontal or supraorbital headache
- Nausea / vomiting / abdominal pain
Differential Diagnosis
Unilateral red eye
- Nontraumatic
- Acute angle-closure glaucoma^
- Anterior uveitis
- Conjunctivitis
- Corneal erosion
- Corneal ulcer^
- Endophthalmitis^
- Episcleritis
- Herpes zoster ophthalmicus
- Inflamed pinguecula
- Inflamed pterygium
- Keratoconjunctivitis
- Keratoconus
- Nontraumatic iritis
- Scleritis^
- Subconjunctival hemorrhage
- Orbital trauma
- Caustic keratoconjunctivitis^^
- Corneal abrasion, Corneal laceration
- Conjunctival hemorrhage
- Conjunctival laceration
- Globe rupture^
- Hemorrhagic chemosis
- Lens dislocation
- Ocular foreign body
- Posterior vitreous detachment
- Retinal detachment
- Retrobulbar hemorrhage
- Traumatic hyphema
- Traumatic iritis
- Traumatic mydriasis
- Traumatic optic neuropathy
- Vitreous detachment
- Vitreous hemorrhage
- Ultraviolet keratitis
^Emergent diagnoses ^^Critical diagnoses
Diagnosis
- Fixed, midposition pupil
- Hazy cornea
- Conjunctival injection most prominent at limbus (ciliary flush)
- Rock-hard globe
- IOP >20 mm Hg
- SLIT LAMP exam shows Cell and Flare which represents visualization of individual cells in the shallow anterior chamber
Definition: 3 signs + 2 symptoms
- At least 3 of these signs:
- IOP >21 mm Hg
- Conjunctival injection
- Corneal epithelial edema
- Mid-dilated nonreactive pupil
- Shallow anterior chamber with occlusion
- At least 2 of these symptoms:
- Ocular pain
- Nausea/vomiting
- History of intermittent blurring of vision with halos
Treatment
- Emergent ophthalmology consult
- Decrease production of aqueous humor:
- timolol 0.5% drop: blocks beta receptors on ciliary epithelium
- apraclonidine 1% drop: alpha-2 adrenergic receptor agonist which increases trabecular outflow
- acetazolamide 500mg IV or PO: blocks productions of HCO3-, which draws Na+ into the eye; water follows by osmosis to form aqueous humour
- Facilitate outflow of aqueous humor:
- pilocarpine 1%–2% drop: parasympatholytic alkaloid acts on muscarinic receptors found on iris sphincter muscle ==> causes muscle to contract ==> miosis
- In USA - green top
- Use one drop every 15 minutes x 2 doses, then every 4 to 6 hours
- Only effective when IOP <40 mm Hg
- pilocarpine 1%–2% drop: parasympatholytic alkaloid acts on muscarinic receptors found on iris sphincter muscle ==> causes muscle to contract ==> miosis
- Reduce volume of aqueous humor:
- mannitol 1–2gm/kg IV: if no contraindications
- Recheck IOP hourly