Glaucoma surgery and induced astigmatism: a systematic review

Area of Science:

• Ophthalmology
• Refractive Surgery
• Glaucoma Management

Background:

• Refractive outcomes of glaucoma surgeries, especially astigmatic changes, require further elucidation.
• Understanding induced astigmatism is crucial for optimizing visual acuity after glaucoma procedures.

Purpose of the Study:

• To review the astigmatic outcomes of various glaucoma surgical techniques.
• To provide guidance on timing of refractive correction post-glaucoma surgery.

Main Methods:

• Review of astigmatic changes following trabeculectomy, deep sclerectomy, minimally invasive glaucoma surgery, and glaucoma drainage device surgery.
• Analysis of the impact of mitomycin C (MMC) on refractive outcomes.
• Evaluation of visual acuity and refractive stability over time.

Main Results:

• Trabeculectomy induces significant with-the-rule astigmatism, shifting to against-the-rule over time, influenced by MMC.
• Non-penetrating surgeries cause similar or lesser astigmatism; minimally invasive glaucoma surgery is astigmatically neutral.
• Refractive changes stabilize around 3 months post-trabeculectomy.

Conclusions:

• Induced astigmatism can reduce unaided visual acuity early after trabeculectomy.
• Delaying new spectacle prescription until 3 months post-surgery is advisable for refractive stability.
• Toric intraocular lenses are a viable option for astigmatism correction in sequential cataract surgery.