The effects of pterygium surgery on anteriorsegment parameters and intraocular lensmeasurements

Purpose: We aimed to examine the effects of pterygium surgery on anterior segment parameters and intraocular lens measurements by comparing pre-and post-surgical data using anterior segment optical coherence tomography (AS-OCT), corneal topography and optical biometry in patients planned for pterygium surgery. Materials and Methods: This study was planned to be conducted on eyes with surgical indication due to pterygium at Van Yüzüncü Yıl University Faculty of Medicine, Ophthalmology Polyclinic. At the pre-surgical and post-surgical (1st Month and 3rd Month) controls of the patients, best corrected visual acuity (BCVA), which was taken with a Snellen chart and converted to logmar, slit light biomicroscopy and dilated fundus examination were performed. Eye films were taken for our patients using an auto refractometer, corneal topography, anterior segment optical coherence tomography, optical biometry, and specular microscopy during preoperative and postoperative follow ups. K1, K2, spherical equivalent and astigmatism values were measured on the autorefractometer film. With corneal topography anterior chamber depth (ACD), central corneal thickness (CCT), Sim-k, Kmax, and Kmin values were recorded, the images obtained using AS-OCT were transferred to the Image J program CCT, peripheral corneal thickness, anterior chamber angle (ACA 500) were recorded manually. It was measured as ıntraocular lens measurements (with Hoffer-Q, Barrett, SRK-T formula) and anterior chamber depth (ACD) was measured with optical biometry. Endothelial cell density (ECD) with specular microscopy, pterygium area, staging, choroidal thickness and choroidal vascular index using macular EDİ-OCT and postoperative complications with anterior segment photo imaging will be recorded. The effects of pterygium surgery on anterior segment parameters and intraocular lens measurement were evaluated by comparing pre-and postoperative data. Results: A statistically significant improvement was found in BCVA (p<0.001). There was no significant difference between preoperative and postoperative values in CCT IX measured by OCT and Orbscan® (p>0.05 and p>0.05, respectively). While no significant change was observed in tPCC measured by OCT, a statistically significant decrease was observed in nPCC (p=0.076 and p<0.001, respectively). No significant difference was observed in endothelial number, choroidal thickness, and KVI values at the end of the preoperative and postoperative 3rd months (p>0.05). While a statistically significant decrease was observed in the cylindrical values measured by ORM compared to the preoperative values, no difference was observed between the 1st and 3rd months postoperatively. No significant change was observed in the spherical equivalent and keratometry (K1-orm and K2-orm) values taken by ORM (p>0.05). While a significant increase was observed in K1-optic and Kmin-orbscan® values compared to preoperative values, no significant difference was observed between postoperative 1st and 3rd month values (p=0.005 and p<0.001, respectively). No significant difference was detected in K2-optic and Kmax-orbscan® values before and after surgery (p=0.259 and p=0.531, respectively). Sim-k value decreased significantly postoperatively compared to preoperative value, but no difference was observed between postoperative 1st and 3rd month (p<0.001). No significant change was detected in ACD-optic and ACD-orbscan® values before and after surgery (p=0.015 and p=0.341, respectively). In ACA 500 parameter, no significant difference was observed between preoperative and postoperative measurements on both nasal and temporal sides (p=0.673 and p=0.073, respectively). Similarly, when the IOL size was examined, a significant decrease was observed in the values measured with the Hoffer-Q and Barret formulas compared to the preoperative values (p=0.002 and p<0.001, respectively). A statistically significant decrease was observed in the IOL size measured with the SRK-T formula in the postoperative 1st and 3rd month values compared to the preoperative values (p=0.001). Conclusion: In our study, it was observed that pterygium surgery caused significant changes in BCVA, astigmatism, and IOL power parameters in the postoperative 1st and 3rd month periods compared to the preoperative period. Our study is also important in that it examines the ACD and CVI parameters in patients with pterygium, which are rarely examined in the literature.