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result(s) for
"phorcides"
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Topography-Guided LASIK: A Prospective Study Evaluating Patient-Reported Outcomes
2023
To evaluate patient-reported outcomes with a validated patient questionnaire following topography-guided LASIK (TG-LASIK).PurposeTo evaluate patient-reported outcomes with a validated patient questionnaire following topography-guided LASIK (TG-LASIK).Patients undergoing TG-LASIK using Phorcides analytic software were prospectively enrolled to receive an adapted Patient-Reported Outcomes with LASIK Symptoms and Satisfaction (PROWL) questionnaire before and 26-weeks after treatment. The main study outcome was the change in the Global Vision Satisfaction Index from the PROWL questionnaire.MethodsPatients undergoing TG-LASIK using Phorcides analytic software were prospectively enrolled to receive an adapted Patient-Reported Outcomes with LASIK Symptoms and Satisfaction (PROWL) questionnaire before and 26-weeks after treatment. The main study outcome was the change in the Global Vision Satisfaction Index from the PROWL questionnaire.Forty-six patients underwent treatment and completed the modified PROWL questionnaire before and 26-weeks after TG-LASIK. The Global Vision Satisfaction Index from the modified PROWL questionnaire improved from 4.07 (3.87-4.26) to 5.00 (4.81-5.19) after the TG-LASIK treatment (p < 0.0001). The study population's binocular uncorrected distance visual acuity was 20/16, 20/12.5, and 20/10 or better in 100%, 87.0%, and 15.2% at 26 weeks post TG-LASIK, respectively.ResultsForty-six patients underwent treatment and completed the modified PROWL questionnaire before and 26-weeks after TG-LASIK. The Global Vision Satisfaction Index from the modified PROWL questionnaire improved from 4.07 (3.87-4.26) to 5.00 (4.81-5.19) after the TG-LASIK treatment (p < 0.0001). The study population's binocular uncorrected distance visual acuity was 20/16, 20/12.5, and 20/10 or better in 100%, 87.0%, and 15.2% at 26 weeks post TG-LASIK, respectively.Patient satisfaction as assessed with the modified PROWL questionnaire is very high after undergoing TG-LASIK using Phorcides analytic software. Patient-reported outcomes add another dimension when assessing treatment efficacy beyond change in visual acuity and corneal architecture, and specialists may consider incorporating such assessments into the consenting process and patient education at large.ConclusionPatient satisfaction as assessed with the modified PROWL questionnaire is very high after undergoing TG-LASIK using Phorcides analytic software. Patient-reported outcomes add another dimension when assessing treatment efficacy beyond change in visual acuity and corneal architecture, and specialists may consider incorporating such assessments into the consenting process and patient education at large.
Journal Article
Patient Reported Visual Outcomes, Dry Eye Symptoms, and Satisfaction Following Topography-Guided LASIK
2025
To assess the subjective satisfaction, visual disturbances, and dry eye symptoms following Phorcides planned Contoura topography-guided LASIK.
This was a single site, single arm, prospective study of patient reported outcomes after bilateral Phorcides planned Contoura topography-guided LASIK. Preoperative and postoperative data were collected for responses on the Patient-Reported Outcomes with LASIK Symptoms and Satisfaction (PROWL-SS) questionnaire (a lower score represented a worse outcome), Ocular Surface Disease Index (OSDI) questionnaire (a higher score represented a worse outcome), refraction, and visual acuity. Linear mixed effect models were used to compare preoperative and postoperative scores on the PROWL-SS for satisfaction, and the frequency, bothersomeness, and visual impact of glare, halo, starbursts, and double images.
A total of 50 subjects completed the study. Mean age was 29.3 ± 5.0 years (range 20 to 39 years). The mean 3-month postoperative satisfaction score was 53.2 higher than the mean preoperative score (p <0.0001). Mean 3-month postoperative scores were 7.4, 13.7, 18.0, and 29.2 higher postoperatively compared to preoperatively for double image, glare, halo, and starburst, respectively. All differences were significant (p <0.0001) with the exception of double image. Mean score on the OSDI questionnaire was 27.0 ± 22.4 preoperatively, compared to 7.5 ± 6.7 at 3 months postoperatively (p <0.0001). Postoperatively, 97% of eyes (90/100) had MRSE within ± 0.5 D and postoperative residual astigmatism was ≤ 0.5 D in 96% of eyes (96/100). Postoperative UDVA was 20/20 or better in 98% (98/100) of eyes, 20/16 or better in 81% (81/100) of eyes, and 20/12.5 or better in 31% (31/100) of eyes.
The results of this study suggest improved patient reported satisfaction, reduced dry eye symptoms, and overall decrease in visual disturbances at 3 months following Phorcides planned Contoura LASIK.
Journal Article
Retrospective Study Comparing Topography-Guided and Wavefront-Optimized LASIK Procedures in a Single Center
2024
To compare visual outcomes of eyes that had laser refractive surgery with the Contoura Phorcides treatment plan and eyes that had laser refractive surgery with the wavefront-optimized treatment plan using the same laser.
Retrospective chart review of clinical outcomes of eyes that had either Contoura with Phorcides (CP) or wavefront-optimized (WFO) corneal refractive procedures using the Wavelight EX500 (Alcon Vision, LLC). Data were collected and compared for uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), refraction, change in postoperative UDVA compared to preoperative CDVA, and change in postoperative CDVA compared to preoperative CDVA.
Total eyes included were 348, with 227 in the CP Group and 121 in the WFO Group. Post-operatively, there was a significantly higher percentage of eyes in the CP Group that were 20/16 or better compared to the WFO Group (57%, 129 eyes, and 17%, 21 eyes, respectively; p < 0.001). The percentage of eyes that gained 1 or more Snellen lines of UDVA compared to preoperative CDVA was higher in the CP Group (47%; 107 eyes) compared to the WFO Group (12%; 14 eyes), which was statistically significant (p < 0.001). Differences in refraction were statistically significant.
Topography-guided and wavefront-optimized treatment profiles both provided excellent refractive results. A higher percentage of eyes that were treated using Contoura with Phorcides achieved 20/16 or better unaided distance vision compared to eyes receiving a wavefront-optimized treatment plan.
Journal Article
Disagreement Between Theoretical and Actual Phorcides Outcomes: Is Phorcides Inferior to Treating on the Manifest Refraction? Letter
2020
Avi Wallerstein,1,2,* Mathieu Gauvin1,2,* 1Department of Ophthalmology and Visual Sciences, McGill University, Montreal, QC, Canada; 2Department of Research & Development, LASIK MD, Montreal, QC, Canada*These authors contributed equally to this workCorrespondence: Avi WallersteinMD Level, 1250 Rene-Levesque Blvd W, Montreal, QC H3B 4W8, CanadaTel +1 514-908-9888 Ext 2273Email awallerstein@lasikmd.com
We read with interest \"Topography-Guided Refractive Astigmatism Outcomes: Predictions Comparing Three Different Programming Methods.\"1 In the Manifest group, the calculated theoretical outcomes revealed an unexpectedly elevated postoperative refractive astigmatism average error of 0.56 ± 0.22 D.1 This large amount of theoretical postoperative cylinder was not replicated in a recent real-world clinical study by the same authors, comparing actual topography-guided LASIK outcomes in Phorcides versus manifest-treated eyes.2 The reported empirical postoperative astigmatism error average in the Manifest group was as low as 0.15 D, fourfold better than that reported in the current theoretical outcomes study.1
View the original paper by Stulting and colleagues
Journal Article
Application of Surgical Protocols for the Treatment of Highly Irregular Astigmatism with Topographic Guided Ablation in a Case of Post-LASIK Ectasia
by
Motwani, Manoj
,
Agu, Emmanuel
,
Yung, Madeline
in
Case Report
,
corneal cross-linking
,
Phorcides
2025
To compare the outcomes of two different surgical planning strategies for topography-guided repair of post-LASIK ectasia.
This is a case report of a patient presenting with post-LASIK ectasia. A retrospective chart review was used to collect details of the ophthalmic exam, as well as ocular imaging such as anterior segment optical coherence tomography and Scheimpflug corneal tomography. Treatment planning was performed initially with the Phorcides analytical engine, and then an enhancement was performed with the LYRA/San Diego Protocol. Epithelium-off corneal cross-linking was performed at 3.0 mW/cm for 30 minutes.
The patient initially presented with a remote history of LASIK and progressive left eye blurring. His uncorrected distance visual acuity (UDVA) was 20/40, with a corrected distance visual acuity (CDVA) of 20/25 with a manifest refraction of -1.25 +1.75 × 180. His central corneal thickness was 529 μm, and corneal topography/tomography demonstrated inferior steepening of the left eye consistent with post-LASIK ectasia. He underwent simultaneous PRK and epithelium-off corneal cross-linking with a treatment plan by Phorcides of -0.14 -0.87 × 001. His vision stabilized at post-operative month 7 to a UDVA 20/40, CDVA 20/20, and manifest refraction of -2.75 +3.50 × 005. He underwent PRK enhancement with a treatment plan by the San Diego Protocol of +0.00 -1.15 × 094, with an outcome of UDVA 20/20, CDVA 20/20, and manifest refraction of -1.00 +0.75 × 174.
The LYRA/San Diego Protocol outperformed Phorcides in a case of corneal ectasia. With appropriate planning, patients with irregular corneas can achieve excellent refractive outcomes.
Journal Article
Predictions of Residual Astigmatism from Surgical Planning for Topographic-Guided LASIK Based on Anterior Corneal Astigmatism (LYRA Protocol) vs the Phorcides Analytic Engine
2020
To identify the laser programming strategy that achieves the highest refractive astigmatism outcomes accuracy between LYRA surgical planning and Phorcides surgical planning.
One hundred one eyes successfully treated with Contoura with LYRA Protocol were retrospectively surgically planned with Phorcides to determine its accuracy. Eighteen eyes that had inaccurate 3 month outcomes with LYRA were also retrospectively planned with Phorcides. Two patients with one eye treated with LYRA and one with Phorcides surgical planning were analyzed for outcomes.
Retrospective Phorcides surgical planning deviated from already successful treatments with LYRA Protocol 51% of the time, with an average astigmatic deviation of 0.69 diopters (D) and an average deviation of 7.1 degrees. The percentage of eyes of the 101 successfully treated with LYRA Protocol then planned with Phorcides differed by 0.5D in 19.8%, by 0.75D in 23.8%, and by 1D in 7.9%. A retrospective analysis with Phorcides of patients treated with LYRA Protocol with residual post-operative astigmatism demonstrated that Phorcides would have increased accuracy in only 33% of patients, and not helped or decreased accuracy in the rest.
Phorcides was significantly less accurate in surgical planning than the LYRA Protocol overall and a 51% of primary patients could have a likelihood of significant residual astigmatism. Phorcides would also have provided a less accurate outcome in the majority of patients that needed secondary enhancement.
Journal Article
Comparative analysis of outcomes following topography-guided laser in situ keratomileusis using manifest refraction versus a new topographic analysis algorithm
by
Dandapani, Ramamurthy
,
Soundarya, B
,
Sachdev, Gitansha S
in
Acuity
,
Algorithms
,
Astigmatism - surgery
2023
Purpose:
To compare the visual outcomes following topography-guided laser in situ keratomileusis (LASIK) treatment using manifest refraction versus a new topography analysis software.
Methods:
A prospective, randomized, observer-masked contralateral study was conducted in the refractive services of a tertiary eye care hospital in South India. Analysis of visual outcomes, corneal higher-order aberrations, and contrast sensitivity were performed at 3 months postoperative visit following uneventful topography-guided LASIK using the Wavelight EX500. One eye was treated with the Contoura platform using manifest refraction (Contoura), while the contralateral eye was treated using an ablation profile planned by the Phorcides Analytic Engine (Phorcides).
Results:
Sixty eyes of 30 patients were included in the study. At 3 months postoperative visit, the uncorrected distance visual acuity (UDVA) in the Contoura and Phorcides groups was logarithm of the minimal angle of resolution (logMAR) 0.04 ± 0.07 and logMAR 0.06 ± 0.1, respectively (P = 0.483). Postoperative manifest refractive spherical error (MRSE) was 0.12 ± 0.22 and − 0.06 ± 0.20 D in the Contoura and Phorcides groups, respectively (P = 0.338). Although higher number of eyes demonstrated a gain in one or more lines of corrected distance visual acuity (CDVA) in the Contoura group (16.6% vs. 6.6%), the difference was not statistically significant (P = 0.361). Vector analysis (Alpins criteria) for postoperative cylinder, contrast sensitivity measurement, and corneal higher-order aberration profile showed no significant difference between the two groups at 3 months postoperative visit (P = 0.213, 0.514, and 0.332, respectively).
Conclusion:
Quantitative and qualitative visual outcomes with the Phorcides Analytic Software were similar to the Contoura treatment using manifest refraction.
Journal Article
Clinical Outcomes After Topography-Guided Refractive Surgery in Eyes with Myopia and Astigmatism – Comparing Results with New Planning Software to Those Obtained Using the Manifest Refraction
2020
To compare clinical outcomes from topography-guided laser refractive surgery based on new planning software to outcomes based on using the manifest refraction.
Single site, two-arm, retrospective chart review.
Clinical outcomes at a single site after topography-guided LASIK using the Wavelight excimer laser were evaluated, with a target postoperative follow-up time of 90 days. Eligible eyes were those that received on-label topography-guided treatment of myopia or myopic astigmatism with correction based on either the manifest refraction or results from the Phorcides Analytical Engine (PAE). Measures analyzed included the uncorrected (UDVA) and best-corrected (CDVA) distance visual acuity, the magnitude of refractive cylinder after surgery, the refractive error and changes from preoperative CDVA.
The study included 115 eyes in the PAE group and 133 eyes in the Manifest group. Significantly more eyes in the PAE group had a CDVA of 20/15 or better (p = 0.05) and a UDVA of 20/15 or better (p = 0.05). Significantly more eyes in the Manifest group had a UDVA of 20/25 or worse (13/133 vs 1/115 in the PAE group, p = 0.002). There were significantly more eyes in the PAE group with no postoperative refractive cylinder (90% vs 77% in the Manifest group, p = 0.004). No eye in either group had a postoperative CDVA a line or worse than their preoperative CDVA. Three eyes in the Manifest group and no PAE eyes have had subsequent enhancement surgery.
Mean results for postoperative refractive astigmatism, CDVA and UDVA were similar between the groups, but the clinical outcomes for the PAE group appeared less variable, with more eyes having no refractive astigmatism and a higher percentage of eyes having 20/15 or better CDVA and UCVA. The objective nature of the PAE is an advantage.
Journal Article