Comparison of Visual Outcomes for Myopia after Refractive Surgery using Femtosecond Laser-assisted and Epipolis LASIK

Abstract Purpose This study was to clinically evaluate the visual outcomes after refractive surgery for myopia using femtosecond laser-assisted in situ keratomileusis (femto-LASIK) and epipolis LASIK (flap-off epi-LASIK). Methods Forty eyes of 27 patients were divided into 2 groups in a retrospective study. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction (MR),corneal asphericity (Q-value) and corneal higher-order aberrations (HOAs) were assessed pre- and postoperatively. Results The pre- and postoperative changes in flattest keratometry reading(K1), steepest keratometry reading(K2), central corneal thickness(CCT), and only Q-value of the anterior surface was statistically significant for both groups (femto-LASIK: P=0.014, P=0.03, P<0.001, P=0.001, respectively; epi-LASIK: all P<0.001). The postoperative corneal thickness spatial profile (CTSP) were statistically significant thinner than preoperative CTSP in both procedures (all P<0.05), and the epi-LASIK was significant thinner than femto-LASIK at 6 mm ring of CTSP (P=0.039). The improvement in LogMAR UDVA after refractive surgery was statistically significant for both groups (P<0.001 for all groups); it was significantly improved for femto-LASIK on day 1 and at 1 week postoperatively (P<0.001, P=0.019, respectively). In analysis of corneal HOAs, there were significant reduction of vertical coma aberration and horizontal secondary astigmatism aberration, and induction of spherical aberration in the front corneal HOAs after femto-LASIK (P=0.021, P=0.001, P=0.001, respectively); in the total corneal HOAs changes were the same pattern as the front corneal HOAs (P=0.007, P=0.004, P<0.001, respectively), but in the back corneal HOAs changes, a few significant induction of vertical coma aberration, and reduction of oblique trefoil aberration and oblique tetrafoil aberration (all P<0.05). In flap-off epi-LASIK, there were only significant induction of SA in the front and total corneal HOAs after surgery (all P<0.05); in the back corneal HOAs, a few significant induced horizontal secondary astigmatism aberration and reduced SA aberration (P=0.027, P=0.011, respectively), however, the back corneal HOAs changes were not significant effect on the total corneal HOAs changes. Conclusion Femto-LASIK showed better early visual outcomes than that noted by epi-LASIK, but there was no significant difference between the outcomes of the 2 procedures 1 week postoperatively.

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Comparison of Visual Outcomes for Myopia after Refractive Surgery using Femtosecond Laser-Assisted and Flap-off Epi-LASIK

10.21203/rs.2.13808/v3 ◽

2020 ◽

Author(s):

JUNJIE PIAO ◽

Woong-Joo Whang ◽

Choun-Ki Joo

Keyword(s):

Visual Acuity ◽

Femtosecond Laser ◽

Refractive Surgery ◽

Distance Visual Acuity ◽

Visual Outcomes ◽

Uncorrected Distance Visual Acuity ◽

Significant Difference ◽

Manifest Refraction ◽

Corrected Distance Visual Acuity ◽

Corneal Asphericity

Abstract Background This study clinically evaluated the visual outcomes after refractive surgery for myopia using femtosecond laser-assisted in situ keratomileusis (femto-LASIK) and epi-LASIK (flap-off). Methods In this prospective cohort study, 40 eyes of 27 patients were divided into two groups depending on the technique used for refractive surgery. Femto-LASIK flaps and epi-LASIK flaps (flap-off) were created using femtosecond laser and Epi-K TM epikeratome, respectively. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction (MR), corneal asphericity (Q-value), and corneal higher-order aberrations (HOAs) were assessed pre- and postoperatively. Results The improvement in LogMAR UDVA after refractive surgery was statistically significant for both groups ( P < 0.001 for all groups); it was significantly improved in the femto-LASIK group, 1 day and 1 week postoperatively ( P < 0.001, P = 0.019, respectively). With regard to the front and total corneal HOAs, there were significant differences in spherical aberrations (Z 4,0 ) between the femto-LASIK and flap-off epi-LASIK groups ( P = 0.016 and P = 0.017, respectively). With regard to the back corneal HOAs, there were significant differences in vertical coma (Z 3,-1 ) aberration, 0.027 ± 0.027 μm (femto-LASIK) and 0.001 ± 0.034 μm (flap-off epipolis LASIK); horizontal secondary astigmatism (Z 4,2 ) aberration, -0.008 ± 0.012 μm (femto-LASIK) and 0.007 ± 0.018 μm (flap-off epipolis LASIK); oblique tetrafoil (Z 4,-4 ) aberration, -0.008 ± 0.029 μm (femto-LASIK) and 0.015 ± 0.026 μm (flap-off epi-LASIK), respectively ( P = 0.018, P = 0.007, and P = 0.022, respectively). However, the back corneal HOA changes did not have a significant effect on the total corneal HOA changes. Conclusion Femto-LASIK yielded better early visual outcomes than did flap-off epi-LASIK, but there was no significant difference between the outcomes of the two procedures, 1 week postoperatively.

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Comparison of Visual Outcomes for Myopia after Refractive Surgery using Femtosecond Laser-assisted and Epipolis LASIK

10.21203/rs.2.13808/v1 ◽

2019 ◽

Author(s):

Junjie Piao ◽

Woong-Joo Whang ◽

Choun-Ki Joo

Keyword(s):

Visual Acuity ◽

Cohort Study ◽

Femtosecond Laser ◽

Prospective Cohort Study ◽

Prospective Cohort ◽

Refractive Surgery ◽

Distance Visual Acuity ◽

Visual Outcomes ◽

Uncorrected Distance Visual Acuity ◽

Significant Difference

Abstract Background This prospective cohort study clinically evaluated the visual outcomes after refractive surgery for myopia using femtosecond laser-assisted in situ keratomileusis (femto-LASIK) and epipolis LASIK (flap-off epi-LASIK).Methods Forty eyes of 27 patients were divided into 2 groups in this prospective cohort study. Femto-LASIK flaps were created using a femtosecond laser; epi-LASIK flaps (flap-off) were made using and Epi-K TM epikeratome. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction (MR), corneal asphericity (Q-value), and corneal higher-order aberrations (HOAs) were assessed pre- and postoperatively.Results The improvement in LogMAR UDVA after refractive surgery was statistically significant for both groups ( P < 0.001 for all groups); it was significantly improved for femto-LASIK at 1 day and 1 week postoperatively ( P < 0.001, P = 0.019, respectively). In analysis of the front and total corneal HOAs, there were significant differences in spherical aberrations (Z 4,0 ) between the femto-LASIK and flap-off epi-LASIK groups ( P = 0.016 and P = 0.017, respectively). In analysis of the back corneal HOAs, there were significant differences in vertical coma (Z 3,-1 ) aberration 0.027 ± 0.027 (femto-LASIK) and 0.001 ± 0.034 (flap-off epi-LASIK); horizontal secondary astigmatism (Z 4,2 ) aberration -0.008 ± 0.012 (femto-LASIK) and 0.007 ± 0.018 (flap-off epi-LASIK); oblique tetrafoil (Z 4,-4 ) aberration -0.008 ± 0.029 (femto-LASIK) and 0.015 ± 0.026 (flap-off epi-LASIK), respectively ( P = 0.018, P = 0.007, and P = 0.022, respectively). However, the back corneal HOA changes did not have a significant effect on the total corneal HOA changes.Conclusion Femto-LASIK yielded better early visual outcomes than that by flap-off epi-LASIK, but there was no significant difference between the outcomes of the 2 procedures 1 week postoperatively.

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Comparison of Visual Outcomes for Myopia after Refractive Surgery using Femtosecond Laser-assisted and Epipolis LASIK

10.21203/rs.2.13808/v2 ◽

2020 ◽

Author(s):

JUNJIE PIAO ◽

Woong-Joo Whang ◽

Choun-Ki Joo

Keyword(s):

Visual Acuity ◽

Cohort Study ◽

Femtosecond Laser ◽

Prospective Cohort Study ◽

Prospective Cohort ◽

Refractive Surgery ◽

Distance Visual Acuity ◽

Visual Outcomes ◽

Uncorrected Distance Visual Acuity ◽

Significant Difference

Abstract Background This prospective cohort study clinically evaluated the visual outcomes after refractive surgery for myopia using femtosecond laser-assisted in situ keratomileusis (femto-LASIK) and epipolis LASIK (flap-off). Methods Forty eyes of 27 patients were divided into 2 groups in this prospective cohort study. Femto-LASIK flaps were created using a femtosecond laser; epipolis LASIK flaps (flap-off) were made using and Epi-K TM epikeratome. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction (MR), corneal asphericity (Q-value), and corneal higher-order aberrations (HOAs) were assessed pre- and postoperatively. Results The improvement in LogMAR UDVA after refractive surgery was statistically significant for both groups ( P < 0.001 for all groups); it was significantly improved for femto-LASIK at 1 day and 1 week postoperatively ( P < 0.001, P = 0.019, respectively). In analysis of the front and total corneal HOAs, there were significant differences in spherical aberrations (Z 4,0 ) between the femto-LASIK and flap-off epipolis LASIK groups ( P = 0.016 and P = 0.017, respectively). In analysis of the back corneal HOAs, there were significant differences in vertical coma (Z 3,-1 ) aberration 0.027 ± 0.027 μm (femto-LASIK) and 0.001 ± 0.034 μm (flap-off epipolis LASIK); horizontal secondary astigmatism (Z 4,2 ) aberration -0.008 ± 0.012 μm (femto-LASIK) and 0.007 ± 0.018 μm (flap-off epipolis LASIK); oblique tetrafoil (Z 4,-4 ) aberration -0.008 ± 0.029 μm (femto-LASIK) and 0.015 ± 0.026 μm (flap-off epipolis LASIK), respectively ( P = 0.018, P = 0.007, and P = 0.022, respectively). However, the back corneal HOA changes did not have a significant effect on the total corneal HOA changes. Conclusion Femto-LASIK yielded better early visual outcomes than that by flap-off epipolis LASIK, but there was no significant difference between the outcomes of the 2 procedures 1 week postoperatively.

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Femtosecond Laser-Assisted in Situ Keratomileusis with Topography-Guided or Asphericity-Adjusted Derived Data: A Comparative Contralateral Eye Study

10.21203/rs.3.rs-1058148/v1 ◽

2021 ◽

Author(s):

Ermano M Alves ◽

Adriana F Lyra ◽

Manuela Tenório ◽

Natália Mesquita ◽

Carolina Bacelar ◽

...

Keyword(s):

Visual Acuity ◽

Refractive Surgery ◽

New Technologies ◽

Spherical Aberration ◽

Double Blind ◽

Distance Visual Acuity ◽

Significant Difference ◽

Contralateral Eye

Abstract Background: Wavefront-optimized laser-assisted in situ keratomileusis (LASIK) ablation is the most commonly performed procedure in refractive surgery, but new technologies have become available. Our goal was to compare topography-guided (Contoura) and asphericity-guided (Custom-Q) customized ablation treatments for the correction of myopia with or without astigmatism.Methods: This prospective, randomized, double-blind, contralateral eye study included 60 eyes of 30 patients with myopia or myopic astigmatism requiring femtosecond LASIK (FemtoLASIK) treatment. For each patient, one eye was randomized to undergo Contoura treatment, and the other underwent Custom-Q abaltion. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refractive spherical equivalent (MRSE), sphere (SPH), cylinder (CYL), 6.0-mm total corneal aberration root mean square (RMS), coma (COMA), trefoil (TREF), and spherical aberration (SA) were measured and analysed after a 1-year follow-up.Results: The UDVA was -0.08 ±0.06 logMAR in Contoura eyes and -0.08 ± 0.05 logMAR in Custom-Q eyes (p = 0.309) after 12 months. Twenty-five eyes (83%) in the Contoura group and twenty-six eyes (87%) in the Custom-Q group had a UDVA of 20/16 at the end of 12 months, and 100% of eyes in both groups reached a UDVA of 20/25 or better. Ninety and 100% of eyes in the Contoura and Custom-Q groups, respectively, achieved a residual CYL ≤0.50 D (p=0.237). No statistically significant difference was observed between the surgical techniques in the preoperative to 1-year postoperative changes for any of the parameters evaluated (MRSE, CYL, RMS, DEF, COMA, TREF, and SA).Conclusions: The Contoura and Custom-Q techniques yielded excellent visual and refractive results, but the evidence did not reveal any clear differences between these two methods after one year of follow-up. Trial registration: RBR-8rs5kt Myopia and Astigmatism Topography-guided Refractive Surgery by Contoura Method Versus Customized by Asphericity in Contralateral Eyes: A prospective Double-blind Randomized Study. UTN code: U111-1243-7257

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Refractive, Topographic, and Aberrometric Results at 2-Year Follow-Up for Accelerated Corneal Cross-Link for Progressive Keratoconus

Journal of Ophthalmology ◽

10.1155/2017/5714372 ◽

2017 ◽

Vol 2017 ◽

pp. 1-6 ◽

Cited By ~ 7

Author(s):

Ercüment Bozkurt ◽

Engin Bilge Ozgurhan ◽

Betul Ilkay Sezgin Akcay ◽

Tugba Kurt ◽

Yusuf Yildirim ◽

...

Keyword(s):

Visual Acuity ◽

Spherical Aberration ◽

Corneal Thickness ◽

Corneal Topography ◽

Wavefront Aberration ◽

Distance Visual Acuity ◽

Uncorrected Distance Visual Acuity ◽

Wavefront Error ◽

The Mean

Purpose. To report the visual, refractive, and corneal topography and wavefront aberration results of accelerated corneal cross-linking (CXL) during a 24-month follow-up.Methods. Forty-seven eyes underwent riboflavin-ultraviolet A-induced accelerated CXL treatment (30 mW/cm2with a total dose of 7.2 joules/cm2). Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical and cylindrical values, keratometry (K) measurements (Ksteep,Kflat,Kavg, andKapex), central corneal thickness, and anterior corneal aberrometric analyses including total wavefront error (WFE), total high order aberration (HOA), astigmatism, trefoil, coma, quadrafoil, secondary astigmatism, and spherical aberration were evaluated.Results. The mean UDVA and CDVA were significantly improved at 1 (p=0.003andp=0.004, resp.) and 2 years after treatment (p=0.001andp=0.001, resp.). The meanKsteep,Kflat,Kaverage, andKapexvalues were significantly lower than baseline at 12 months (p=0.008,p=0.024,p=0.001, andp=0.014, resp.) and 24 months (p=0.014,p=0.017,p=0.001, andp=0.012, resp.). Corneal thickness showed a significant decrease at 1 month. Total HOA and coma decreased significantly at the 12-month (p=0.001andp=0.009, resp.) and 24-month visits (p=0.001andp=0.007, resp.).Conclusion. Accelerated CXL (30 mW/cm2) was found to be effective in improving UDVA, CDVA, corneal topography readings, total HOA, and coma aberrations during the 24-month follow-up.

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Comparison of corneal optical quality after SMILE, wavefront-optimized LASIK and topography-guided LASIK for myopia and myopic astigmatism

10.21203/rs.3.rs-308202/v1 ◽

2021 ◽

Author(s):

Yu Zhang ◽

Xiaoxiao Sun ◽

Yueguo Chen

Keyword(s):

Visual Acuity ◽

Optical Path Difference ◽

Path Difference ◽

Mean Value ◽

Optical Quality ◽

Distance Visual Acuity ◽

Visual Outcomes ◽

Corneal Aberrations ◽

Uncorrected Distance Visual Acuity ◽

Significant Difference

Abstract Purpose: To compare visual outcomes and corneal optical quality after small incision lenticule extraction (SMILE) , wavefront-optimized (WFO) FS-LASIK and topography-guided customized ablation treatment (TCAT) FS-LASIK for myopia. Methods: This prospective study included 283 eyes of 283 myopic patients who underwent SMILE or FS-LASIK according to the patient's wishes. FS-LASIK patients were randomly assigned to use WFO or TCAT ablation. There were 102 eyes, 100 eyes and 81eyes in the SMILE group, WFO group and TCAT group, respectively. The combined corneal topographer and tomographer system (Sirius) was used to measure corneal aberrations and optical quality. Visual outcomes and corneal aberrations were compared among the three groups.Results: At postoperative 1 and 6 months, there were no significant differences in uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) among the three groups (P > .05). Postoperative manifest refractive spherical equivalent was similar among the groups (P > .05). There was statistically significant difference in cylinder at 1 month among the three groups, with the highest mean value in TCAT group (P < .05). The corneal optical path difference (OPD), root mean square of corneal astigmatism and strehl ratio (SR) were the most superior in the TCAT group at postoperative 1 and 6 months (P < .05).Conclusion: SMILE, WFO FS-LASIK and TCAT FS-LASIK provided similar visual results. TCAT FS-LASIK could induce fewer corneal OPD and astigmatism, and higher SR than the others. However, a better algorithm for TCAT FS-LASIK is needed to decrease postoperative residual astigmatism.

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Corneal Spherical Aberration and Corneal Asphericity after Small Incision Lenticule Extraction and Femtosecond Laser-Assisted LASIK

Journal of Ophthalmology ◽

10.1155/2017/4921090 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Hui Zhang ◽

Yan Wang ◽

Hua Li

Keyword(s):

Visual Acuity ◽

Femtosecond Laser ◽

Spherical Aberration ◽

Laser In Situ Keratomileusis ◽

Anterior Surface ◽

Small Incision Lenticule Extraction ◽

Distance Visual Acuity ◽

Small Incision ◽

Corneal Asphericity ◽

Lenticule Extraction

Purpose. To investigate corneal spherical aberration and corneal asphericity after small incision lenticule extraction (SMILE) and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK). Methods. This study enrolled 70 patients having SMILE and 64 subjects receiving FS-LASIK. The preoperative spherical equivalent (SE) was −5.83 ± 1.23 diopters (D) and −6.20 ± 1.52 D, respectively. The uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), SE, corneal spherical aberration, and asphericity over the 6.0 mm cornea were evaluated preoperatively and postoperatively. Results. At 6 months, the UDVA, CDVA, and SE were −0.12 ± 0.11, −0.05 ± 0.05, and −0.16 ± 0.19 D in SMILE and −0.10 ± 0.06, −0.03 ± 0.06, and −0.08 ± 0.25 D in FS-LASIK. There was no difference between groups in the postoperative UDVA, CDVA, or SE (P>0.05). SMILE showed lower inductions of spherical aberration along the anterior surface and the total cornea and less increases in corneal asphericity of the anterior surface postoperatively than FS-LASIK (P<0.01). There were significant correlations between the changes in spherical aberration and corneal asphericity (P<0.001). Conclusions. SMILE and FS-LASIK exhibited excellent visual results and refractive outcomes. SMILE induced less increase in corneal spherical aberration and better preserved the corneal asphericity of the anterior corneal surface than FS-LASIK. Corneal asphericity changes contributed to the corneal spherical aberration changes following SMILE and FS-LASIK.

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A randomised controlled trial comparing femtosecond laser-assisted cataract surgery versus conventional phacoemulsification surgery: 12-month results

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2020-316311 ◽

2020 ◽

pp. bjophthalmol-2020-316311

Author(s):

Nick Stanojcic ◽

Harry William Roberts ◽

Vijay K Wagh ◽

Ji-Peng Olivia Li ◽

Khayam Naderi ◽

...

Keyword(s):

Visual Acuity ◽

Randomised Controlled Trial ◽

Femtosecond Laser ◽

Cataract Surgery ◽

Controlled Trial ◽

Corneal Thickness ◽

Posterior Capsular Opacification ◽

Distance Visual Acuity ◽

Patient Reported ◽

Randomised Controlled

AimsTo report 12-month outcomes of randomised controlled trial comparing conventional phacoemulsification surgery (CPS) with femtosecond laser-assisted cataract surgery (FLACS).MethodsThis was a single-centre, prospective single-masked randomised case-controlled trial. Four hundred patients were randomised to CPS or FLACS with the LenSx platform (Alcon Laboratories Inc.). Visual acuity, refraction, central corneal thickness, endothelial cell loss (ECL), adverse events and quality of life outcomes, using EuroQOL 5-dimensions (EQ-5D-3 L) and cataract surgery patient-reported outcome measures (PROMs) questionnaires (Cat-PROM5), were recorded.ResultsTwo hundred and thirty four patients (58.5%) attended 12-month follow-up (116 FLACS, 118 CPS). Mean LogMAR unaided distance visual acuity) (±SD) was 0.12 (0.18) with FLACS and 0.13 (0.19) with CPS (p=0.68; 95% Confidence Interval [CI]−0.06,0.04). Mean spherical equivalent (SE) refraction was −0.1±0.6 diopters (D) with FLACS and −0.2±0.6 D with CPS (p=0.44; 95% CI −0.09, 0.21). Mean corrected distance visual acuity (±SD) was −0.01 (0.1) with FLACS and 0(0.1) with CPS (p=0.45; 95% CI −0.04,0.02). Two patients per group underwent YAG laser capsulotomy for posterior capsular opacification (p=1). Mean ECL (per mm2±SD) was 301±320 with FLACS and 228±303 with CPS (p=0.07; 95% CI −7.26, 153.26). Mean Cat-PROM scores (±SD) were −5.5 (2.6) with FLACS and −5.8 (2.5) with CPS (p=0.3; 95% CI 0.31,1.01). EQ5-3DL mean index score (±SD) was 0.92 (0.13) with FLACS and 0.89 (0.14) with CPS (p=0.1; 95% CI −0.1, 0.01). Vector analysis comparing manual limbal relaxing incisions (LRIs) and intrastromal femtosecond laser-assisted astigmatic keratotomies (iFAKs) showed a greater correction index (p=0.02; 95% CI 0.06 to 0.60) and smaller difference vector (p=0.046; 95% CI −0.54, −0.01) with iFAK.ConclusionsThere were no differences in vision, refraction, adverse postoperative events or PROMs between FLACS and CPS groups at 12 months. iFAKs may provide more effective astigmatic correction compared to LRIs, 12 months postoperatively.

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Comparison of refractive outcomes after photorefractive keratectomy with different optical zones using Mel 90 excimer laser

10.21203/rs.2.10534/v2 ◽

2020 ◽

Author(s):

Dae Hwan Shin ◽

Yong Woo Lee ◽

Ji Eun Song ◽

Chul Young Choi

Keyword(s):

Excimer Laser ◽

Spherical Aberration ◽

Corneal Thickness ◽

Photorefractive Keratectomy ◽

Q Value ◽

Thickness Change ◽

Refractive Outcomes ◽

Significant Difference ◽

Optical Zone

Abstract Background: To compare the changes in clinical outcomes and the degree of regression between a 6.0 mm optical zone (6.0 OZ) and 6.5 mm optical zone (6.5 OZ) following photorefractive keratectomy (PRK).Methods: The records of 95 eyes that had undergone PRK with a 6.0 OZ (n = 40) and a 6.5 OZ (n = 55) were retrospectively reviewed. We compared data including the spherical equivalent of manifest refraction (SE of MR), simulated K (Sim K), thinnest corneal thickness, change in thinnest corneal thickness (the initial value divided by corrected diopter [ΔTCT/CD]), Q value, corneal higher order aberrations (HOAs) and spherical aberration (SA) pre-operation, at 3 and 6 months postoperative and at the last follow-up visit (Mean; 20.71 ± 10.52, 17.47 ± 6.57 months in the 6.0 and 6.5 OZ group, respectively).Results: There were no significant differences in the SE of MR, Sim K and UDVA between the 6.0 OZ group and the 6.5 OZ group over 1 year of follow-up after PRK, and the 6.0 OZ group required less ΔTCT/CD than the 6.5 OZ group. The 6.5 OZ group showed better results in terms of post-operative HOAs of RMS, SA and Q value. When comparing that pattern of change in Sim K, there was no significant difference between the 6.0 OZ group and the 6.5 OZ group.Conclusions: The clinical refractive outcomes and regression after PRK using Mel 90 excimer laser with a 6.0 OZ were comparable to those with a 6.5 OZ.

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Reduced High-order Aberrations using Wavefront-guided Partial Photorefractive Keratectomy and Accelerated Epithelium-off Corneal Cross-linking for Keratoconus

International Journal of Keratoconus and Ectatic Corneal Diseases ◽

10.5005/jp-journals-10025-1146 ◽

2017 ◽

Vol 6 (2) ◽

pp. 73-77

Author(s):

Guillermo Rocha ◽

Victor Penner ◽

Kylee Lewis

Keyword(s):

Visual Acuity ◽

Spherical Aberration ◽

Corneal Thickness ◽

Case Series ◽

High Order ◽

Photorefractive Keratectomy ◽

Cross Linking ◽

Distance Visual Acuity ◽

Uncorrected Distance Visual Acuity ◽

High Order Aberrations

ABSTRACT Purpose To demonstrate clinical outcomes of epithelium-off corneal cross-linking (CXL) in combination with wavefront-guided photorefractive keratectomy (PRK) for the treatment of keratoconuns. Materials and methods Total, 28 keratoconic eyes of 21 patients were included. The Sirius Wavefront Analyzer (SCHWIND eye-tech-solutions GmbH and Co. KG) was used to evaluate the high-order aberrations (HOAs). The coupled Amaris 750S excimer laser then performed a PRK of no more than 40 μm using the measured HOA. The CXL was then carried out respecting the standard of 400 μm of corneal thickness. Results The average age was 32 (15—48) years. Uncorrected distance visual acuity (UDVA) improved from 0.58 to 0.31 logMAR (p < 0.001), with best corrected distance visual acuity (CDVA) improving from 0.03 to 0.02 logMAR (p = 0.7). On manifest refraction, the average spherical component decreased from –1.87 to –1.40 D (0.47 ± 2.12, p = 0.4). Cylinder decreased from 2.18 to 0.87 D (1.31 ± 1.14 D, p < 0.001). All HOAs decreased: total HO 0.94 to 0.58 (0.36 ± 0.42, p = 0.05); spherical aberration: 0.142 to –0.018 (0.160 ± 0.160, p < 0.001); secondary astigmatism: 0.21 to 0.11 (0.10 ± 0.11, p = 0.02); coma: 0.80 to 0.42 (0.38 ± 0.47, p = 0.03); trefoil: 0.33 to 0.29 (0.04 ± 0.17, p = 0.7). Conclusion Utilizing HOA to guide the laser treatment in combination with CXL resulted in a significant decrease of HOA at 6 months postprocedure. This is a small case series, but demonstrates a promising trend of improved HOA. Considering that keratoconic eyes have very irregular surfaces with significant HOA, reducing these aberrations should improve best corrected quality of vision. Having longer follow-up and greater numbers may demonstrate a clearer improvement. How to cite this article Penner V, Lewis K, Rocha G. Reduced High-order Aberrations using Wavefront-guided Partial Photorefractive Keratectomy and Accelerated Epithelium-off Corneal Cross-linking for Keratoconus. Int J Kerat Ect Cor Dis 2017;6(2):73-77.

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