Complications of cataract surgery

1. Intraoperative complications

• Posterior capsular rupture (PCR) with or without vitreous loss
  • May lead to dropped lens fragments, cystoid macular edema, retinal detachment, infection, and poor intraocular lens (IOL) support.
• Zonular dialysis or capsular-bag instability
  • More likely with pseudoexfoliation, trauma, or mature cataract.
• Iris trauma or iris prolapse
• Corneal endothelial injury / Descemet membrane detachment
• Incomplete cortical cleanup or retained lens matter
• IOL-related problems
  • Incorrect IOL power, decentration, tilt, or placement in an unsuitable location.
• Suprachoroidal hemorrhage
  • Rare but severe, presenting with sudden shallowing of the anterior chamber, pain, and increased posterior pressure.
• Thermal wound burn during phacoemulsification.

2. Early postoperative complications

• Corneal edema
  • Often transient; can be prolonged in patients with endothelial disease such as Fuchs dystrophy.
• Anterior uveitis / excessive postoperative inflammation
• Raised intraocular pressure (IOP)
  • May result from retained viscoelastic, inflammation, pigment, or steroid response.
• Wound leak and shallow anterior chamber
• Hyphema or other intraocular bleeding
• IOL decentration, pupillary capture, or early dislocation
• Retained lens fragments
  • Can cause persistent inflammation, corneal edema, high IOP, and macular edema.
• Acute postoperative endophthalmitis
  • A vision-threatening intraocular infection. Suspect with worsening pain, redness, reduced vision, hypopyon, or vitritis. It requires urgent ophthalmic treatment. Contemporary reported incidence is at least about 0.1% in the referenced text. Kanski's Clinical Ophthalmology, 10th ed., p. 328.
• Toxic anterior segment syndrome (TASS)
  • Sterile, intense anterior-segment inflammation, usually within 12-48 hours. It must be distinguished from infectious endophthalmitis.
• Cystoid macular edema (CME), or Irvine-Gass syndrome
  • Causes blurred central vision, commonly peaking about 6-10 weeks after surgery. Risk rises with vitreous loss, iris prolapse, or vitreous incarceration in the wound. The Wills Eye Manual, p. 824.

3. Late postoperative complications

• Posterior capsular opacification (PCO), or “after-cataract”
  • The most common late complication. Residual lens epithelial cells proliferate on the posterior capsule, causing gradual blur, glare, and sometimes monocular diplopia. It occurs in about 20-25% of patients and is generally treated with Nd:YAG laser capsulotomy. Kanski's Clinical Ophthalmology, 10th ed., p. 332.
• IOL subluxation or dislocation
  • Can occur months to years later, especially with weak zonules.
• Capsular phimosis / anterior capsular contraction
• Chronic uveitis
• Chronic or delayed-onset endophthalmitis
• Secondary glaucoma
  • Due to steroid response, retained material, inflammation, pigment dispersion, or IOL-related mechanisms.
• Retinal tear or retinal detachment
  • Risk is higher in high myopia, posterior capsular rupture with vitreous loss, previous retinal pathology, and younger male patients.
• Persistent CME
• Dysphotopsias
  • Glare, halos, arcs of light, or negative dysphotopsia (temporal dark shadow).
• Postoperative refractive surprise
  • Residual myopia, hypermetropia, astigmatism, or anisometropia.
• Dry eye symptoms
• Ptosis
  • Usually transient; can follow lid-speculum use or postoperative inflammation.

Red-flag symptoms after surgery

• Increasing pain or marked redness
• Sudden reduction of vision
• Flashes, floaters, or a curtain-like visual-field defect
• Severe photophobia
• Purulent discharge
• Persistent nausea/vomiting with eye pain, suggesting high IOP