Timing of Intraocular Lens Power Calculation Post Pterygium Surgery

In patients requiring further cataract surgery, the clinical constancy of keratometric parameters after pterygium removal is essential. Consequently, the prober timing of intraocular lens power calculation post pterygium removal is mandatory to establish proper visual and refractive outcome after cataract surgery. The purpose of this research is to learn more about the time of keratometric and refractive stability after pterygium excision using the conjunctival autografting technique, to get a stable refractive and keratometric readings and subsequently, a proper intraocular lens power calculation. This interventional, prospective, and non-randomized study included eighteen eyes of sixteen cases with primary nasal pterygium. Patients with recurrent and pseudo pterygia were excluded. All cases were exposed to complete ocular examination, including UCVA and BCVA, slit lamp examination, applanation tonometry, and autorefractometry. Intraocular lens (IOL) master machine was used for obtaining the keratometric readings and for intraocular lens (IOL) power calculation. Pterygium operation was done under local infiltration anesthesia using the conjunctival autografting procedure. Follow up post-operatively was done at 1 day, 1 week, 1, 3, and 6 months. Changes in UCVA, BCVA, keratometric values and IOL power calculation readings after pterygium surgery were evaluated. There was significant enlargement in mean UCVA and mean BCVA during all the follow up visits after pterygium operation. Besides, there was a significant rise in mean k1 during all the follow up visits after pterygium surgery. As regards mean K2 and the mean astigmatic values, they were significantly decreased after surgery. There was statistically significant decrease in mean IOL power at 1, 3, and 6 months postoperatively. Statistically, the differences between mean IOL power at one month, three months, and six months were non-significant. Pterygium excision using the conjunctival autografting technique is associated with postoperative increased K1, decreased K2, increased mean keratometric readings and decreased the astigmatic value. Stable IOL power calculation values was achieved one month postoperatively. Consequently, intraocular lens power calculation and cataract surgery must be suspended for at least one month post pterygium operation in eyes with cataract and pterygium.