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Acute Angle-Closure Glaucoma — IOP-Lowering Sequence and Definitive Iridotomy

System: Ophthalmology • Reviewed: Sep 2, 2025 • Step 1Step 2Step 3

Synopsis:

Severe ocular pain, halos, N/V, and mid-dilated fixed pupil with corneal edema. Begin ED IOP-lowering sequence (topical β-blocker + α-agonist + carbonic anhydrase inhibitor + hyperosmotic agent) and topical pilocarpine once IOP decreased; arrange urgent laser peripheral iridotomy.

Key Points

  • Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
  • Set objective targets and reassess frequently.
  • Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.

Algorithm

  1. Confirm diagnosis with tonometry; initiate topical combo and systemic agents as needed.
  2. Once IOP falling, add pilocarpine; analgesia/antiemetics as needed.
  3. Urgent ophthalmology for laser iridotomy; educate on triggers and fellow-eye prophylaxis.

Clinical Synopsis & Reasoning

Severe ocular pain, halos, N/V, and mid-dilated fixed pupil with corneal edema. Begin ED IOP-lowering sequence (topical β-blocker + α-agonist + carbonic anhydrase inhibitor + hyperosmotic agent) and topical pilocarpine once IOP decreased; arrange urgent laser peripheral iridotomy.


Treatment Strategy & Disposition

Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.


Epidemiology / Risk Factors

  • Risk varies by comorbidity and precipitants; see citations for condition‑specific data.

Investigations

TestRole / RationaleTypical FindingsNotes
Tonometry and slit-lamp examDiagnosisElevated IOP, shallow AC, corneal edema
Gonioscopy (when safe)ConfirmationClosed/narrow angle
Medication review for precipitantsEtiologyAnticholinergics/sympathomimeticsStop triggers

High-Risk & Disposition Triggers

TriggerWhy it mattersAction
IOP very high with corneal edema, severe pain, nausea/vomitingVision threatED IOP-lowering sequence; urgent ophthalmology
Monocular functional eyeDisability riskAdmit for close monitoring
Delayed access to ophthalmologySafetyArrange emergent transfer
Anticholinergic/sympathomimetic medication triggerDrug-inducedStop offending agents
Asian ancestry/hyperopiaAnatomic riskProphylaxis of fellow eye

Pharmacology

Medication/InterventionMechanismOnsetRole in TherapyLimitations
Topical timolol + apraclonidine/brimonidine + dorzolamideIOP reductionMinutesFirst-line comboContraindications apply
Acetazolamide 500 mg IV/PO and Mannitol 1–2 g/kg IV (if severe)Systemic IOP reductionMinutes‑hoursRapid loweringRenal/CV cautions
Pilocarpine 1–2% drops (after initial IOP reduction)MioticMinutesOpen angle via pupillary constrictionIneffective at very high IOP initially
Definitive laser peripheral iridotomyDefinitiveHours‑daysPrevents recurrenceProphylaxis for fellow eye

Prognosis / Complications

  • Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.

Patient Education / Counseling

  • Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.

References

  1. AAO acute angle-closure management statements — Link

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