Understanding "OCCI"
The term "OCCI" most commonly refers to "Opposite Clear Corneal Incisions" in ophthalmology, specifically in cataract surgery with phacoemulsification. This is a surgical technique used to reduce pre-existing corneal astigmatism during cataract procedures.
Clinical Context and Application
Based on the available evidence, OCCIs are surgical incisions made on the steep meridian of the cornea during phacoemulsification cataract surgery 1. The technique involves:
- Placement: Incisions are made on-axis (on the steep meridian) opposite to each other
- Purpose: To reduce preoperative corneal astigmatism while performing routine phacoemulsification with foldable intraocular lens (IOL) implantation
- Effectiveness: Mean reduction in corneal astigmatism of 0.50 diopters (statistically significant, P<0.001) 1
Surgical Outcomes
The evidence demonstrates that on-axis OCCIs provide:
- Surgically induced astigmatism (SIA): Mean of 1.57 D (95% CI: 1.42 to 1.71) 1
- Spherical equivalent change: Negligible at +0.02 D (95% CI: -0.08 to +0.12), which can be ignored during biometry calculations 1
- Reliability: Weak association with patient age and axis of preoperative astigmatism, indicating consistent results across patient populations 1
Clinical Significance
OCCIs represent a practical and reliable method for addressing preexisting corneal astigmatism during cataract surgery without requiring additional procedures or significantly altering the refractive outcome. The technique is evaluated 6-8 weeks postoperatively through keratometry 1.
Important Caveat
The term "OCCI" should not be confused with other medical abbreviations. In different contexts, similar abbreviations may refer to online consultations (OC), oral octreotide capsules (OOC), or the occipito-atlantal cistern (OAC), but these are distinct entities with different clinical applications 2, 3, 4.