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Military Medicine Jan 2017To compare visual performance, marksmanship performance, and threshold target identification following wavefront-guided (WFG) versus wavefront-optimized (WFO)... (Randomized Controlled Trial)
Randomized Controlled Trial
PURPOSE
To compare visual performance, marksmanship performance, and threshold target identification following wavefront-guided (WFG) versus wavefront-optimized (WFO) photorefractive keratectomy (PRK).
METHODS
In this prospective, randomized clinical trial, active duty U.S. military Soldiers, age 21 or over, electing to undergo PRK were randomized to undergo WFG (n = 27) or WFO (n = 27) PRK for myopia or myopic astigmatism. Binocular visual performance was assessed preoperatively and 1, 3, and 6 months postoperatively: Super Vision Test high contrast, Super Vision Test contrast sensitivity (CS), and 25% contrast acuity with night vision goggle filter. CS function was generated testing at five spatial frequencies. Marksmanship performance in low light conditions was evaluated in a firing tunnel. Target detection and identification performance was tested for probability of identification of varying target sets and probability of detection of humans in cluttered environments.
RESULTS
Visual performance, CS function, marksmanship, and threshold target identification demonstrated no statistically significant differences over time between the two treatments. Exploratory regression analysis of firing range tasks at 6 months showed no significant differences or correlations between procedures. Regression analysis of vehicle and handheld probability of identification showed a significant association with pretreatment performance.
CONCLUSIONS
Both WFG and WFO PRK results translate to excellent and comparable visual and military performance.
Topics: Adult; Female; Firearms; Humans; Linear Models; Male; Military Personnel; Night Vision; Photorefractive Keratectomy; Prospective Studies; Task Performance and Analysis; Visual Acuity
PubMed: 28051986
DOI: 10.7205/MILMED-D-15-00576 -
Journal of Cataract and Refractive... Sep 2014To report the visual, refractive, and clinical outcomes of simultaneous topography-guided partial photorefractive keratectomy (PRK) and corneal collagen crosslinking...
PURPOSE
To report the visual, refractive, and clinical outcomes of simultaneous topography-guided partial photorefractive keratectomy (PRK) and corneal collagen crosslinking (CXL) in eyes with keratoconus.
SETTING
Private practice surgery center, Dubai, United Arab Emirates.
DESIGN
Retrospective cohort study.
METHODS
Refraction, uncorrected (UDVA) and corrected (CDVA) distance visual acuities, flat and steep keratometry (K) readings, and complications were evaluated 1, 3, 6, and 12 months postoperatively.
RESULTS
The study enrolled 31 eyes of 31 patients aged 21 to 42 years. All study parameters showed a statistically significant improvement at 3, 6, and 12 months over baseline values. At 12 months, the mean UDVA improved to 0.23 logMAR±0.33 (SD) from 0.79±0.36 logMAR (P<.001) and the CDVA improved to 0.06±0.07 logMAR from 0.28±0.20 logMAR (P<.001). The mean defocus decreased from 3.45±1.60 diopters (D) to 1.88±1.58 D (P<.001). The flat K and steep K readings showed significant flattening. The mean refractive astigmatism decreased from -2.77±1.47 D to -0.98±0.76 D (P<.001). The improvement in study parameters plateaued after 3 months.
CONCLUSION
Simultaneous topography-guided partial PRK and CXL was effective, safe, and stable in keratoconus patients.
FINANCIAL DISCLOSURE
No author has a financial or proprietary interest in any material or method mentioned.
Topics: Adult; Collagen; Combined Modality Therapy; Corneal Stroma; Corneal Topography; Cross-Linking Reagents; Humans; Keratoconus; Lasers, Excimer; Photochemotherapy; Photorefractive Keratectomy; Photosensitizing Agents; Refraction, Ocular; Retrospective Studies; Riboflavin; Surgery, Computer-Assisted; Ultraviolet Rays; Visual Acuity; Young Adult
PubMed: 25135534
DOI: 10.1016/j.jcrs.2013.12.017 -
Romanian Journal of Ophthalmology 2020To compare late mid-term results of two different surgical approaches of surface excimer laser ablation for myopic and astigmatic errors in contralateral eyes of the... (Comparative Study)
Comparative Study
To compare late mid-term results of two different surgical approaches of surface excimer laser ablation for myopic and astigmatic errors in contralateral eyes of the same patients. Prospective cohort study. A photorefractive keratectomy technique was performed on the right eye and single-step transepithelial photorefractive keratectomy on the left eye of the same patient, in 2012. Postoperative uncorrected and corrected visual acuities, manifest refraction, contrast sensitivity, objective scatter index, tear film stability assessed by serial measurements of objective scatter index and aberrometry as well as occurrence of haze, were compared between groups of eyes. Thirty-two eyes of 16 patients with a mean time of follow-up of 35.2 +/ - 5.0 months (range 30-46 months) were evaluated. No significant differences were observed in postoperative results (visual acuity, spherical equivalent, defocus equivalent, higher-order aberrations, objective scatter index, tear film stability and contrast sensitivity). Contrast sensitivity tended to be better in transepithelial photorefractive keratectomy technique, under photopic lighting conditions without glare and mesopic conditions both with glare and without glare, however, no statistically significant differences were found. No eye presented corneal haze at the last examination. No statistically significant differences in visual acuity, refractive results, contrast sensitivity, objective scatter index, tear film stability or ocular aberrometry were observed between the two surface ablation techniques.
Topics: Adult; Contrast Sensitivity; Cornea; Female; Follow-Up Studies; Humans; Laser Therapy; Lasers, Excimer; Male; Middle Aged; Myopia; Photorefractive Keratectomy; Prospective Studies; Refraction, Ocular; Visual Acuity; Young Adult
PubMed: 32685784
DOI: No ID Found -
International Ophthalmology Jan 2021To evaluate the clinical outcomes of small incision lenticule extraction (SMILE) and aberration-free transepithelial photorefractive keratectomy (AF t-PRK) in patients...
PURPOSE
To evaluate the clinical outcomes of small incision lenticule extraction (SMILE) and aberration-free transepithelial photorefractive keratectomy (AF t-PRK) in patients with low to moderate myopic astigmatism, including visual acuity, refractive outcomes, astigmatic vector analysis and corneal aberrometric changes.
METHOD
This retrospective comparative case series study involved 110 right eyes of 110 patients who underwent either SMILE (55 eyes) or AF t-PRK (55 eyes). Visual acuity, manifest refractive error and corneal higher-order aberrations (HOAs) were measured and analyzed at baseline, 1 month and 3 months after operation. The safety and efficacy indices, and vector parameters were also compared.
RESULT
1 month postoperatively, the mean uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA) and spherical equivalent refraction (SE) were better after SMILE than AF t-PRK (logMAR UDVA, - 0.03 ± 0.07 and - 0.006 ± 0.07, P = 0.050; logMAR CDVA, - 0.06 ± 0.07 and - 0.03 ± 0.07, P = 0.043; SE, - 0.04 ± 0.25 and 0.15 ± 0.26, P < 0.001). However, these parameters were comparable between the groups at 3 months after surgery. Residual astigmatism ≤ 0.25 diopters was observed in 74.5% and 90.9% (P = 0.023) of the eyes at one month and in 87.3% and 85.5% (P = 0.781) of the eyes at 3 months after SMILE and AF t-PRK, respectively. There were no significant differences between the groups in any of the vector parameters at 1 month or 3 months after surgery. Coma and total HOAs after SMILE were significantly higher than AF t-PRK (1 month coma, 0.49 ± 0.23 and 0.29 ± 0.15, P < 0.001; 1 month total RMS HOAs, 0.65 ± 0.20 and 0.54 ± 0.14, P = 0.001; 3 months coma, 0.50 ± 0.22 and 0.30 ± 0.17, P < 0.001; 3 months total RMS HOAs, 0.68 ± 0.20 and 0.55 ± 0.17, P < 0.001).
CONCLUSION
In this study, both SMILE and AF t-PRK were effective and comparable for correction of low to moderate myopic astigmatism. AF t-PRK group induced less coma and total HOAs than SMILE.
Topics: Astigmatism; Humans; Lasers, Excimer; Myopia; Photorefractive Keratectomy; Refraction, Ocular; Retrospective Studies; Treatment Outcome
PubMed: 32901403
DOI: 10.1007/s10792-020-01582-3 -
European Journal of Ophthalmology Sep 2022To evaluate the safety, efficiency, short term stability, and sensory results of photorefractive keratectomy (PRK) in anisometropic in non-compliant children with...
OBJECTIVE
To evaluate the safety, efficiency, short term stability, and sensory results of photorefractive keratectomy (PRK) in anisometropic in non-compliant children with correction.
METHODS
Twelve eyes of 12 children with an age range: 6-17 years and anisometropic amblyopia who underwent PRK under general anesthesia to correct the dioptric difference between the eyes were included in this study. A complete ophthalmic assessment including refractive status, uncorrected and corrected distance visual acuity (UDVA & CDVA), and binocular vision status using the Worth 4-dot test and stereopsis were performed before and 1, 3, 6, and 12 months after PRK.
RESULTS
The mean preoperative CDVA was 0.34 ± 0.24 LogMAR which showed a statistically significant improvement at 12 months (0.20 ± 0.19, p = 0.024) after surgery compared to the preoperative assessment. (p = 0.003) The mean preoperative UDVA was 0.63 ± 0.24 LogMAR that increased to 0.44 ± 0.24, 0.32 ± 0.16, 0.25 ± 0.19, and 0.25 ± 0.19 LogMAR at 1, 3, 6, and 12 months after PRK, respectively. One to three lines improvement in UDVA and CDVA was seen in 10 (83.4%) and 8 eyes (66.7%); while one line UDVA and CDVA loss was seen in one (8.3%) and one (8.3%) eye and unchanged UDVA and CDVA was seen in 1 (8.3%) and 3 eyes (25%), respectively. The mean preoperative stereoacuity was 341.9 ± 245.7 s of arc, which significantly improved to 166.6 ± 87.5 s of arc 12 months after PRK. (p = 0.012).
CONCLUSION
PRK was an effective surgical alternative to improve visual acuity and stereopsis in anisometropic children who did not cooperate with conventional methods of amblyopia therapy.
Topics: Adolescent; Amblyopia; Child; Follow-Up Studies; Humans; Lasers, Excimer; Myopia; Photorefractive Keratectomy; Refraction, Ocular; Treatment Outcome
PubMed: 35156869
DOI: 10.1177/11206721211073033 -
Cornea Aug 2022The aim of this study was to identify preoperative predictors for the occurrence of early severe postoperative pain in patients undergoing photorefractive keratectomy...
PURPOSE
The aim of this study was to identify preoperative predictors for the occurrence of early severe postoperative pain in patients undergoing photorefractive keratectomy (PRK). The implementation of preoperative screening methods may facilitate more specific or aggressive pain therapies specifically targeted to individuals at a high risk of experiencing severe postoperative pain.
METHODS
This was exploratory research that included patients who underwent PRK. Before PRK, patients were administered a sociodemographic questionnaire, the Pain Catastrophizing Scale, and the State-Trait Anxiety Inventory and underwent corneal sensitivity and conditioned pain modulation (CPM) tests. Post-PRK pain was assessed using a pain intensity visual analog scale (VAS), and the short-form McGill Pain Questionnaire (SF-MPQ) was completed 21 days before PRK and 1, 24, 48, and 72 hours after PRK. Spearman correlations were calculated for pain scores and preoperative predictors.
RESULTS
This research included 34 eyes of 34 patients. Preoperative corneal sensitivity was positively correlated with post-PRK pain scores as assessed by VAS and SF-MPQ (rho = 0.39 and rho = 0.41, respectively, P < 0.05). No correlations were found between Pain Catastrophizing Scale, State-Trait Anxiety Inventory, and CPM scores and post-PRK pain scores ( P > 0.05).
CONCLUSIONS
Abnormal presurgical corneal sensitivity was a protective marker for severe pain after PRK, while scores as assessed by VAS and SF-MPQ and CPM were not related to postoperative pain.
Topics: Acute Pain; Humans; Lasers, Excimer; Myopia; Pain Measurement; Pain, Postoperative; Photorefractive Keratectomy; Refraction, Ocular
PubMed: 35543577
DOI: 10.1097/ICO.0000000000003037 -
Journal of Cataract and Refractive... Jun 2022
Review
Topics: Bandages, Hydrocolloid; Contact Lenses, Hydrophilic; Humans; Lasers, Excimer; Photorefractive Keratectomy
PubMed: 34753881
DOI: 10.1097/j.jcrs.0000000000000861 -
Indian Journal of Ophthalmology Dec 2020We aimed to compare transepithelial photorefractive keratectomy (TPRK) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK) for myopia treatment by analyzing...
Corneal curvature, asphericity, and aberrations after transepithelial photorefractive keratectomy and femtosecond laser-assisted keratomileusis for myopia: A prospective comparative study.
PURPOSE
We aimed to compare transepithelial photorefractive keratectomy (TPRK) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK) for myopia treatment by analyzing corneal curvature, asphericity (Q-value), and corneal aberration.
METHODS
Corneal topography was measured before and 6 months after the TPRK or FS-LASIK surgery. We measured and compared corneal curvature (sagittal curvature in the 1- to 7-mm zones), change in keratometric measurements (Kmpost - Kmpre, ΔK), Q-values (from the vertex of the 6-, 7-, 8-, and 9-mm zones), higher-order aberration (HOA), vertical and horizontal trefoil (Z3 and Z3), vertical and horizontal coma (Z3 and Z3), and spherical aberration (Z4) between the two surgery groups.
RESULTS
The sagittal curvature Δ K in the 1-mm zone after TPRK was significantly higher than after FS-LASIK. The Δ K/ΔSE (ΔSE [spherical equivalent] = SEpre - SEpost) ratio in the 1- to 4-mm diameter zones was significantly higher after TPRK than after FS-LASIK. The preoperative Q-values of the 6- and 7-mm zones did not differ between the treatment groups, but postoperative values were significantly higher following FS-LASIK than following TPRK. HOA, Z4, and Z3 were all significantly higher after surgery in both groups. Postoperative Z3 was significantly higher following TPRK but not following FS-LASIK. There were no postoperative differences in aberrations in either group; however, the change in HOA and Z3 was significantly greater following FS-LASIK.
CONCLUSION
TPRK changes the corneal curvature to a greater extent and the visual quality (Q-value, aberrations) to a lesser extent than FS-LASIK.
Topics: Cornea; Humans; Keratomileusis, Laser In Situ; Lasers, Excimer; Myopia; Photorefractive Keratectomy; Prospective Studies; Visual Acuity
PubMed: 33229675
DOI: 10.4103/ijo.IJO_1106_20 -
BMC Ophthalmology Jun 2018To compare the clinical outcomes of wavefront-optimized (WFO) transepithelial photorefractive keratectomy (trans-PRK) and corneal wavefront-guided (CWFG) trans-PRK for... (Comparative Study)
Comparative Study Observational Study
BACKGROUND
To compare the clinical outcomes of wavefront-optimized (WFO) transepithelial photorefractive keratectomy (trans-PRK) and corneal wavefront-guided (CWFG) trans-PRK for myopic eyes with moderate to high astigmatism.
METHODS
One hundred ninety-six eyes (196 patients) with moderate to high astigmatism (≥ 1.75 D) treated with WFO or CWFG trans-PRK (101 and 95 eyes, respectively) were retrospectively registered. Safety, efficacy, predictability, vector analysis, and corneal aberrations were compared between groups preoperatively and at 6 months postoperatively.
RESULTS
At postoperative 6 months, the mean logMAR uncorrected distance visual acuity was similar in the WFO (- 0.07 ± 0.08) and CWFG (- 0.07 ± 0.07) groups. Safety, efficacy, and predictability of refractive and visual outcomes were also similar. The correction indices were 1.02 ± 0.14 and 1.03 ± 0.13 in the WFO and CWFG groups, respectively, with no significant difference. The absolute values of the angle of error were significantly higher in the WFO group (2.28 ± 2.44 vs. 1.40 ± 1.40; P = 0.002). Corneal total root mean square higher-order aberrations and corneal spherical aberrations increased postoperatively in both groups; however, the change was smaller in the CWFG group. Corneal coma showed a significant increase postoperatively only in the WFO group.
CONCLUSIONS
WFO and CWFG trans-PRK are safe and effective for correcting moderate to high astigmatism. However, CWFG trans-PRK provides a more predictable astigmatism correction axis and fewer induced corneal aberrations.
Topics: Adolescent; Adult; Astigmatism; Corneal Topography; Corneal Wavefront Aberration; Epithelium, Corneal; Female; Follow-Up Studies; Humans; Lasers, Excimer; Male; Myopia; Photorefractive Keratectomy; Postoperative Period; Refraction, Ocular; Retrospective Studies; Treatment Outcome; Visual Acuity; Young Adult
PubMed: 29940974
DOI: 10.1186/s12886-018-0827-x -
BMC Ophthalmology Aug 2018To evaluate the safety, efficacy, and the refractive outcomes of single-step transepithelial photorefractive keratectomy (TransPRK) for the correction of mild, moderate,...
BACKGROUND
To evaluate the safety, efficacy, and the refractive outcomes of single-step transepithelial photorefractive keratectomy (TransPRK) for the correction of mild, moderate, and high myopia.
METHODS
This study consecutively recruited 32 high myopic eyes, 32 mild myopic and 32 moderate myopic eyes. Eyes with myopia that had undergone TransPRK treatment. Pre- and post-operative visual and refractive data, corneal Higher Order Aberration (HOA) as well as safety and efficacy indices were analyzed at 6 months postoperatively.
RESULTS
Six months after TransPRK, the manifest refraction spherical equivalent (SE) was not significantly between high myopia group and moderate myopia group (p = 0.636). No eyes lost ≥2 lines of corrected distant visual acuity (CDVA) in high myopic eyes. The uncorrected distance visual acuity (UDVA) was significantly higher in low and moderate myopia groups than the high myopia group (P < 0.001; P = 0.002). The CDVA was not significantly different between moderate and high myopia groups (P = 0.057). There was no significant difference in mean safety index between high myopia group (1.01 ± 0.14) and mild myopia group (1.08 ± 0.15) (P > 0.05). The mean safety index was significantly higher in the moderate myopia group (1.16 ± 0.23) than in the high myopia group (1.01 ± 0.14) (P = 0.002). The efficacy index was significantly higher in the moderate myopia group (1.05 ± 0.20) than in the high myopia group (0.89 ± 0.17) (P = 0.02), and there was no significant difference between the high myopia group (0.89 ± 0.17) and the low myopia group (0.96 ± 0.16) (P = 0.14).
CONCLUSIONS
The mean safety index was over 1.0 in the three groups. TransPRK showed acceptable safety and efficacy in the moderate myopic eyes, as well as mild and high myopic eyes. High myopic eyes got very similar refractive results with moderate myopic eyes six months postoperatively. The safety and efficacy indexes were not significantly different between the high myopia group and the low myopia group.
Topics: Adult; Analysis of Variance; Female; Humans; Lasers, Excimer; Male; Myopia; Myopia, Degenerative; Photorefractive Keratectomy; Prospective Studies; Refraction, Ocular; Visual Acuity; Young Adult
PubMed: 30153819
DOI: 10.1186/s12886-018-0888-x