ESCRS - P188 - VECTOR ANALYSIS AND PROGNOSTIC FACTORS FOR FEMTOSECOND ASTIGMATIC KERATOTOMY IN POST-KERATOPLASTY ASTIGMATISM

VECTOR ANALYSIS AND PROGNOSTIC FACTORS FOR FEMTOSECOND ASTIGMATIC KERATOTOMY IN POST-KERATOPLASTY ASTIGMATISM

Published 2024 - 28th ESCRS Winter Meeting

Reference: P188 | Type: Presented Poster & Poster | DOI: 10.82333/r59j-ae18

Authors: Bayan Alsaif 1 , Sumayah hamza Banaji* 1 , askar alshaibani 2 , abdulaziz alsomali 3

1ophthalmology,king Fahd hospital of the university, imam Abdulrahman bin Faisal university,dammam,Saudi Arabia, 2ophthalmology,Dhahran Eye Specialist Hospital,dhahran ,Saudi Arabia, 3ophthalmology,college of medicine, king Faisal university ,al-ahsa,Saudi Arabia

Purpose

To analyze different tomographic and refractive parameters for predicting successful visual outcomes following femtosecond laser-assisted arcuate keratotomy (FSAK) for post-keratoplasty astigmatism.

Setting

retrospective chart review. Dhahran Eye Specialist Hospital, Dhahran, Saudi Arabia.

Methods

this is a retrospective study evaluating patients with astigmatism following penetrating keratoplasty (PKP) or deep anterior lamellar keratoplasty (DALK) who underwent FSAK. Vector analysis using the Alpins’ method was done to calculate surgically induced astigmatism (SIA). An improvement of 3 lines of Early Treatment Diabetic Retinopathy Study (ETDRS) lines was used for successful outcomes. outcome was measured at 3 months and 17 months.

Results

This study included  106 eyes from 104 patients (65 males and 39 females). Mean age of 31.8±8.6 years. 89.4% (n=93) cases were keratoconus (KC), 3.8% (n=4) scar, 3.8% (n=4) granular dystrophy, 1.9% (n=2) post-LASIK ectasia, and 1.0% (n=1) macular dystrophy. Uncorrected visual acuity (UCVA) improved from 1.02±0.53 logarithm minimal angle of resolution (logMAR) to 0.87±0.49 logMAR (p=0.01) at 3 months and to 0.92±1.08 logMAR (p=0.57) at 17 months. Best spectacle-corrected visual acuity (BSCVA) improved from 0.41±0.30 logMAR to 0.31±0.19 logMAR (p<0.01) at 3 months and to 0.23±0.27 logMAR (p<0.01) at 17 months. Success was achieved in 50% (n=53) and 49% (n=52) at 3 and 17 months follow-up, respectively. The success group showed worse pre-operative UCVA (1.21±0.56 vs 0.83±0.44 logMAR; p<0.01), worse pre-operative BSCVA (0.50±0.36 vs 0.33±0.19 logMAR; p=0.01). preoperative UCVA had an area under the curve of 0.721(95%CI: 0.622-0.820; p< 0.01). The Youden’s optimal cutoff point was 0.90 logMAR (equivalent Snellen 20/159) with 76.9% sensitivity and 35.2% specificity. Flattening index (FI) was 87% in DALK and 73% in PKP (p=0.14). Correction index (CI) was (99% and 86%; p=0.18) for DALK and PKP respectively. The success of the astigmatic surgery for DALK and PKP was (44% vs 42%; p=0.29) respectively.

Conclusion

Improvement of at least three lines was achieved in 49% of patients who underwent FSAK following PKP or DALK, this improvement was achieved in patients who had a worse pre-operative UCVA.