Varenicline Solution Nasal Spray for the Treatment of Dry Eye Disease Following LASIK.

INTRODUCTION: The purpose of this study is to evaluate the use of a varenicline solution nasal spray (VNS) for reducing the signs and symptoms of dry eye following laser in situ keratomileusis (LASIK). METHODS: Subjects electing to undergo LASIK were randomized to VNS (study group) or placebo/vehicle (control group) and initiated treatment with the nasal spray twice daily 28 days prior to surgery with continued treatment for 84 days following LASIK. After initiation of treatment, subjects were seen on the day of surgery and postoperatively on Days 1, 7, 28, 84 (3 months) and 168 (6 months). The primary outcome measure was the mean change in NEI-VFQ-25, a 25-item dry eye questionnaire, from baseline to 3 months. The second primary outcome measure was the mean change in corneal fluorescein staining. Secondary outcome measures included evaluation of tear break-up time, Schirmer testing, tear osmolarity and eye dryness score (EDS). RESULTS: Twenty subjects were enrolled in each group and successfully underwent LASIK. Both groups demonstrated an improvement in the National Eye Institute Visual Function Questionnaire (NEI-VFQ) at 3 months. The study group demonstrated improved corneal staining scores at months 1 and 3. Similarly, the study group demonstrated improvement in tear osmolarity scores versus the placebo group at the same time points. Although the study group was numerically greater than placebo for each time point for both corneal staining and tear osmolarity, the differences were not statistically significant for any primary or secondary outcome measures. CONCLUSION: VNS is a dry eye treatment option for patients following LASIK and may have potential benefit for patients hoping to avoid additional topical medications. The results were not statistically significant compared to placebo in this trial, and further investigation of the use of VNS following LASIK in a larger trial would be beneficial.

Laser in situ keratomileusis (LASIK) is a very successful refractive surgery option for patients hoping to reduce or eliminate their need for spectacles. Signs and symptoms of dry eye disease are very common after LASIK owing to the transection of corneal nerves that occurs during the procedure, and many patients are advised to manage it with frequent instillation of artificial tears. This study evaluated the use of a varenicline solution nasal spray, a recently introduced pharmacologic option that stimulates natural tear production through activation of the trigeminal nerve pathway. This is the first study to evaluate the use of the varenicline solution nasal spray in patients after refractive surgery and demonstrates that it could represent a favorable, ocular surface-sparing option for patients to minimize the signs and symptoms of dry eye following LASIK, a procedure known to trigger symptoms of dry eye disease.

Femtosecond thin-flap laser assisted in situ keratomileusis for correction of post-penetrating keratoplasty ametropia: long-term outcome.

PURPOSE: To evaluate the long-term clinical outcomes of femtosecond thin-flap LASIK (femto-LASIK) for correction of refractive error after penetrating keratoplasty in keratoconus-affected eyes. SETTING: a private ophthalmology clinic. DESIGN: Prospective interventional case series. METHODS: This prospective interventional case series enrolled 22 eyes of 22 patients who underwent femto-LASIK for the management of post-penetrating keratoplasty ametropia. The refractive error, uncorrected (UDVA), and corrected (CDVA) distance visual acuities and vector analysis were reported in short-term and long-term period after surgery. RESULTS: The mean age was 32.7 ± 7.5 years (range, 23 to 47 years) at the surgery time. The average time between PK and femto-LASIK was 42.5 ± 31.7 months. The average follow-up duration after femto-LASIK was 81.2 ± 18.6 months. The mean preoperative UDVA significantly improved from 0.47 ± 0.15 logMAR to 0.35 ± 0.14 logMAR at 12 months (P = 0.048) and 0.4 ± 0.17 at final follow-up exam (P = 0.007). CDVA was 0.22 ± 0.1 at baseline which improved to 0.18 ± 0.15 and 0.15 ± 0.1 logMAR at 12 and 81 months, respectively. (Ps = 0.027, 0.014). The mean cylinder before surgery was - 5.04 ± 1.4D which significantly decreased to -1.5 ± 0.8 D at 12 months postoperatively. (P < 0.001). There was a significant increase in refractive astigmatism from 12 months to 81 months postoperatively (-3.1 ± 2.0, P = 0.002). At the final visit, the efficacy index was 0.83, and the safety index was 1.16. CONCLUSIONS: Despite the short-term outcome indicated that femo-LASIK was effective for correction of post-keratoplasty ametropia during short-term period, a notable regression in its effect was observed in the long-term follow-up. Therefore, the predictability of this technique might decrease in the long-term.

Comparative Analysis of Corneal Higher-Order Aberrations after Laser-Assisted In Situ Keratomileusis, Photorefractive Keratectomy, and Small Incision Lenticule Extraction with Correlations to Change in Myopic Q-Value and Spherical Equivalent with and without Astigmatism.

Background: This retrospective chart review compared the higher-order aberrations (HOAs) among photorefractive keratectomy (PRK), laser-assisted in situ keratomileusis (LASIK), and small incision lenticule extraction (SMILE) alongside changes in spherical equivalent (SEQ) and corneal shape (Q-value). Methods: Analyzing 371 myopic eyes, including 154 LASIK, 173 PRK, and 44 SMILE cases, Pentacam imaging was utilized pre-operatively and at one-year post-operative visits. Results: All procedures resulted in 100% of patients achieving an uncorrected distance visual acuity (UDVA) of 20/40 or better, with 87% of LASIK and PRK, and 91% of SMILE patients having 20/20 or better. Significant increases in HOAs were observed across all procedures (p < 0.05), correlating positively with SEQ and Q-value changes (LASIK (0.686, p < 0.05), followed by PRK (0.4503, p < 0.05), and SMILE (0.386, p < 0.05)). Vertical coma and spherical aberration (SA) were the primary factors for heightened aberration magnitude among the procedures (p < 0.05), with the largest contribution in SMILE, which is likely attributed to the centration at the corneal apex. Notably, PRK showed insignificant changes in vertical coma (-0.197 µm ± 0.0168 to -0.192 µm ± 0.0198, p = 0.78), with an increase in oblique trefoil (p < 0.05). Conclusions: These findings underscore differences in HOAs among PRK, LASIK, and SMILE, helping to guide clinicians.

Effect of corneal cross-linking on biomechanical changes following transepithelial photorefractive keratectomy and femtosecond laser-assisted LASIK.

Purpose: To evaluate the change in corneal biomechanics in patients with postoperative ectasia risk when combining two common laser vision correction procedures (tPRK and FS-LASIK) with cross-linking (in tPRK Xtra and FS-LASIK Xtra). Methods: The study included 143 eyes of 143 myopic, astigmatic patients that were divided into non-cross-linked refractive surgery groups (non-Xtra groups, tPRK and FS-LASIK) and cross-linked groups (Xtra groups, tPRK Xtra and FS-LASIK Xtra) according to an ectasia risk scoring system. The eyes were subjected to measurements including the stress-strain index (SSI), the stiffness parameter at first applanation (SP-A1), the integrated inverse radius (IIR), the deformation amplitude at apex (DA), and the ratio of deformation amplitude between apex and 2 mm from apex (DARatio2mm). The measurements were taken preoperatively and at 1, 3, and 6 months postoperatively (pos1m, pos3m, and pos6m). Posterior demarcation line depth from the endothelium (PDLD) and from the ablation surface (DLA) were recorded at pos1m. Results: SP-A1 significantly decreased, while IIR, deformation amplitude, and DARatio2mm increased significantly postoperatively in all four groups (p < 0.01)-all denoting stiffness decreases. In the FS-LASIK group, the changes in IIR, DA, and DARatio2mm were 32.7 ± 15.1%, 12.9 ± 7.1%, and 27.2 ± 12.0% respectively, which were significantly higher (p < 0.05) compared to 20.1 ± 12.8%, 6.4 ± 8.2%, and 19.7 ± 10.4% in the FS-LASIK Xtra group. In the tPRK group, the change in IIR was 27.3 ± 15.5%, significantly larger than 16.9 ± 13.4% in the tPRK Xtra group. The changes of SSI were minimal in the tPRK (-1.5 ± 21.7%, p = 1.000), tPRK Xtra (8.4 ± 17.9%, p = 0.053), and FS-LASIK Xtra (5.6 ± 12.7%, p = 0.634) groups, but was significant in the FS-LASIK group (-12.1 ± 7.9%, p < 0.01). After correcting for baseline biomechanical metrics, preoperative bIOP and the change in central corneal thickness (△CCT) from pre to pos6m, the changes in the IIR in both FS-LASIK and tPRK groups, as well as DA, DARatio2mm and SSI in the FS-LASIK group remained statistically greater than their corresponding Xtra groups (all p < 0.05). Most importantly, after correcting for these covariates, the changes in DARatio2mm in the FS-LASIK Xtra became statistically smaller than in the tPRK Xtra (p = 0.017). Conclusion: The statistical analysis results indicate that tPRK Xtra and FS-LASIK Xtra effectively reduced the biomechanical losses caused by refractive surgery (tPRK and FS-LASIK). The decrease in corneal overall stiffness was greater in FS-LASIK than in tPRK, and the biomechanical enhancement of CXL was also higher following LASIK than after tPRK.

Fungal Keratitis Post-FemtoLASIK: A Novel Therapeutic Approach with LASIK Flap Autograft and Penetrating Keratoplasty: A Case Report.

Introduction: This case report describes a rare case of fungal keratitis following femtoLASIK. Despite targetted antifungal therapy, this case necessitated an innovative surgical approach to manage an unexpected corneal perforation. Case Presentation: A 35-year-old male presented 3 weeks post-femtoLASIK for myopic astigmatism with discomfort and reduced vision in his right eye. He was diagnosed with fungal keratitis surgery caused by Purpureocillium lilacinum and was treated with a myriad of therapy. Unfortunately, the patient developed corneal perforation during flap lift and flap bed irrigation. An innovative approach involving a tectonic autograft using a viable LASIK flap, followed by prompt penetrating keratoplasty, was utilised. Conclusion: This technique was effective and able to mitigate the progression to an open globe.

Corneal foreign body post laser in-situ keratomileusis: Diagnosis, management, outcome and review of literature.

Purpose: To report a case of metallic corneal foreign-body (CFB) penetrating the Laser in situ keratomileusis (LASIK) flap and its successful outcome. To highlight usefulness of Anterior Segment Optical Coherence Tomography (ASOCT) in diagnosis and management of post-LASIK CFB. To enumerate other similar cases published in literature. Method: A 30-year-old male presented to the emergency department of a tertiary eye care centre with a metallic CFB. He had undergone uneventful LASIK elsewhere 4-years back. He was unaware of any trauma. CFB removal was attempted elsewhere but abandoned as CFB appeared deeply embedded. ASOCT showed CFB had penetrated LASIK flap and lodged into midstroma, 207 µm deep. CFB was successfully removed in operation theatre along with the application of cyanoacrylate glue and bandage contact lens. A review of literature for CFB in post-LASIK patients was done through PubMed search. Result: Postoperative course was uncomplicated and there was a follow up period of 4 months. Vision improved to unaided 20/20 and N/6 from preoperative 20/60 and N/10. Review of literature of 24 patients showed Post-LASIK FB was more common in males (79%). None of the patients except for one had protective eye-wear. Metallic FB was most common followed by organic FB. Flap complications were present in seven patients. Diffuse lamellar keratitis (DLK) and epithelial ingrowth were the most common post-FB removal complications occurring in six (25%) and four (16.6%) patients respectively. Conclusion: Post-LASIK patients with CFB need to be inspected for flap related complications. CFB can be successfully removed, although DLK, epithelial ingrowth, microbial keratitis, astigmatism, can occur post-CFB removal. ASOCT can delineate CFB and flap related details and thus is an additional useful imaging tool in such scenarios.

Three cases of non-infectious necrotizing stromal keratitis after corneal refractive surgery.

We reported three cases of aseptic necrotizing stromal keratinitis after corneal refractive surgery (two with small incision lenticule extraction and one with femtosecond laser-laser-assisted insitu keratomileusis). There were three young women who had undergone corneal refractive surgery had white aseptic infiltrating foci along or away from the stroma in both eyes or one eye on regular review, all of whom denied systemic disease or chronic ocular disease. Two patients were diagnosed with aseptic necrotizing corneal stromal inflammation, and one patient was diagnosed with delayed necrotizing corneal stromal inflammation. In our opinion, before corneal refractive surgery, medical history inquiry is very important. More attention should be paid to patients with vaccination history and foreign travel history. In addition, the possibility of delayed corneal stromal inflammation should be considered for patients with poor binocular corrected vision.

Advances in Transepithelial Photorefractive Keratectomy versus Laser-Assisted In Situ Keratomileusis.

(1) Background: Laser-assisted refractive surgery is a safe and effective surgical correction of refractive error. For most patients, both the newer Trans-PRK and the established LASIK technique can produce the required surgical correction, sparking the question of which technique should be opted for. (2) Methods: The study prospectively evaluated 121 patients (230 eyes) for at least one month postoperatively; 66 patients (126 eyes) and 45 patients (85 eyes) returned for 6 months and 1 year follow-up. (3) Results: No statistical difference was recorded at 1 week or 1 month post-operation. At 6 months, a difference was found for spherical diopters (Trans-PRK -0.0476 ± 0.7012 versus FS-LASIK +0.425 ± 0.874, p = 0.004) and spherical equivalent (Trans-PRK -0.1994 ± 0.0294 versus FS-LASIK +0.225 ± 0.646, p = 0.025) but not for CYL D (Trans-PRK -0.3036 ± 0.5251 versus FS-LASIK -0.4 ± 0.820, p = 0.499). Uncorrected visual acuity was better for Trans-PRK 6 months post-operation (UCVA logMAR 0.02523 versus 0.0768 logMAR; p = 0.015 logMAR). At 1-year, Trans-PRK was favored for spherical diopters (Trans-PRK -0.0294 ± 0.6493 versus FS-LASIK +0.646 ± 0.909, p < 0.001) and spherical equivalent (Trans-PRK -0.218 ± 0.784 versus FS-LASIK 0.372 ± 1.08, p = 0.007). Overall speed in visual recovery, variance of results and surgically induced astigmatism were in favor of Trans-PRK. (4) Conclusions: The study reported improvements for Trans-PRK patients, with both techniques found to be safe and effective.

Magnitude and Determinants of Awareness Regarding Refractive Surgeries Among Saudi Adults.

Objectives: This study aimed to present the magnitude and determinants of awareness about refractive surgery among the adult Saudi population and recommend knowledge improvement. Methods: This web-based cross-sectional study was conducted between June 2020 and May 2021 across various regions of Saudi Arabia on the adult Saudi population. A total of 11 close-ended questions regarding indication, contraindication, preparation and surgery procedures were asked. The awareness scores were grouped as 'good' (≥6) or 'poor' (≤5). Demographic and ocular parameters were associated with the outcomes. Results: Of the 6,746 participants, 6,580 (response rate = 97.5%) completed the survey. The participation of younger women and older men was greater than their proportions in the population, while older women participated less than their proportion. Good awareness about refractive surgery was noted in 1,165 (17.7%; 95% confidence interval: 16.2-18.0) participants. Women (P <0.001), the 18-29 age group (P <0.001), residents of the central region of Saudi Arabia (P <0.001), health professionals (P <0.001), health sector students (P = 0.0004), people with myopia (P <0.001) and history of refractive surgery (P <0.001) were associated with good awareness. Women (adjusted odds ratio [AOR] = 1.5; P <0.001), health sector students (AOR = 1.57; P <0.001), and residents in the central region (AOR = 1.27; P <0.001) were independent predictors of awareness. Knowledge about contraindications for surgery was good in more than one-third of the participants. Of the 535 participants who underwent surgery in the past, 452 (84.5%) were satisfied with their outcomes. Conclusion: Awareness of refractive surgeries is low in the adult Saudi population. Targeted counseling is recommended to improve the knowledge and acceptance of refractive surgery.

LASIK is associated with early cataract surgery in healthy patients.

PURPOSE: To evaluate the association between LASIK and early cataract phacoemulsification surgery (PE). METHODS: A matched case-control study was conducted. Cases were otherwise healthy adults with a history of LASIK. Groups were paired according to corrected-distance visual acuity (CDVA), axial length, and cataract grade. RESULTS: A total of 213 patients were included. 85 patients were classified as post-LASIK group and 128 as controls. The mean age at the time of LASIK was 42.32 ± 9.24 years. The mean CDVA before PE was 0.29 ± 0.19 Log MAR in post-LASIK group and 0.34 ± 0.22 Log MAR in controls (p = 0.07). The mean axial length was 23.99 ± 1.78 mm in post-LASIK group and 23.62 ± 0.98 mm in controls (p = 0.085). The mean nuclear cataract grading was 1.36 in post-LASIK group and 1.47 in controls (p = 0.34). The mean age at the time of PE was 60.18 ± 7.46 years in post-LASIK group and 67.35 ± 9.28 in controls (p < 0.0005). The difference between the mean age of LASIK and the mean age of PE was 17.85 ± 5.72 years. There was a positive association between the post-LASIK group and the age of PE ≤ 55 years (OR: 4.917, 95% CI: 2.21-10.90, p < 0.001). CONCLUSION: LASIK may be associated with early PE. Patients with LASIK had a 7-year earlier PE compared to a matched control group.

Ray-Tracing Customization in Myopic and Myopic Astigmatism LASIK Treatments for Low and High Order Aberrations Treatment: 2-Year Visual Function and Psychometric Value Outcomes of a Consecutive Case Series.

Purpose: The safety and long-term efficacy of automated ray-tracing customized myopic and myopic astigmatic femtosecond laser-assisted LASIK. Methods: This consecutive case series retrospective analysis, of 20 subjects (40 eyes) treated with automated raytracing named Wavelight Plus, to include low and high order aberrations based on a three-dimensional custom virtual eye for each case-calculated from interferometry data-obtained from a single diagnostic device that also provides Hartman-Shack Wavefront and Scheimpflug tomography data. We evaluated before and after the customized LASIK procedure: visual acuity, refractive error, high order aberrations, contrast sensitivity, and psychometric post-operative visual function data. Results: At 24 months, the comparison of the pre-operative to the post-operative refractive and visual function value changes in average were: subjective manifest refraction from -4.38 ± 2.54 diopters (D) (range -9.75 to -1.25 D) to +0.11 ± 0.19 D; subjective manifest refractive astigmatism from -0.76 ± 0.91 D (range -2.75 to 0 D) to -0.13 ± 0.16 D, corneal astigmatism from -1.16 ± 0.64 D (range -0.2 to -2.8) to -0.47 ± 0.11 D. 65% of the eyes studied demonstrated an increase of at least one line of vision, while from the same group 38% demonstrated 2 lines of increase. High order aberrations, contrast sensitivity as well as the subjective psychometric input based on the VFQ-25 questionnaire demonstrated actual improvement. Conclusion: This longer-term follow-up, single-arm retrospective consecutive case series documents LASIK treatment customization that appears to be safe and effective in the correction of myopia and myopic astigmatism. Markedly improved objective and subjective visual function post-operatively, underlying the potential importance of simultaneously attempting to correct high order aberrations and improving the spatial alignment of total, measured human eye optics.

Limitations of and Solutions to Using 6 mm Corneal Spherical Aberration and Q Value after Laser Refractive Surgery.

This study aimed to evaluate the spherical aberration (SA) in different corneal areas before and after femtosecond laser-assisted in situ keratomileusis (fLASIK) and transepithelial photorefractive keratectomy (tPRK), with the goal of identifying the limitations of and potential improvements in using SA within a 6 mm area. The study included 62 patients who underwent fLASIK and tPRK. Complete eye examinations including keratometry, corneal epithelial thickness, central corneal thickness, and topography were performed preoperatively and postoperatively. Anterior, posterior, and total corneal aberrations were measured preoperatively and three months postoperatively, with pupil diameters ranging from 2 to 8 mm. In the fLASIK group, compared to the preoperative SA, the anterior and total SA increased postoperatively in the 6 and 7 mm areas. In the tPRK group, meanwhile, the anterior and total SA of the 5 mm or larger areas increased postoperatively. An area of 6 mm or larger showed an increase in correlation with the changes in Q value and refractive correction. As the corneal SA and asphericity in the 6 mm zone cannot specifically demonstrate the status of areas smaller than 6 mm or changes in the optical zone after laser refractive surgery, comparison with normal values in various areas of the cornea is necessary.

Ocular surface changes following computer use in post-LASIK patients.

PURPOSE: To assess the impact of computer use on the ocular surface of individuals after laser in situ keratomileusis (LASIK). METHODS: The dry eye symptoms and ocular surface of 18 post-LASIK young individuals and 18 controls were evaluated before and after performing a 30-min task on a computer without (Visit 1) and with (Visit 2) initial instillation of artificial tears. Symptoms were assessed using the Ocular Surface Disease Index (OSDI), Symptom Assessment in Dry Eye questionnaire version two (SANDE II) and Computer Vision Syndrome Questionnaire (CVS-Q). The ocular surface was assessed by measuring corneal higher order aberrations, tear meniscus height (TMH), conjunctival redness, blink rate and incomplete blinking, lipid layer thickness (LLT) and non-invasive keratograph break-up time (NIKBUT). RESULTS: SANDE II scores were >0 after the computer task in both groups (p ≤ 0.01). SANDE II and CVS-Q scores did not differ between LASIK and controls (p ≥ 0.43). Greater bulbar-temporal conjunctival redness, TMH and LLT and shorter NIKBUT were found after computer use in the LASIK group (p ≤ 0.04), whereas no changes were observed in the controls (p ≥ 0.20). Lower SANDE II and CVS-Q scores were reported at Visit 2 compared with Visit 1 in both groups (p ≤ 0.01). Likewise, no worsening of dry eye signs was observed at Visit 2 (p ≥ 0.11). CONCLUSIONS: Ocular symptoms reported during computer use were comparable between the groups. However, a worsening of dry eye signs was mostly observed in post-LASIK individuals. The instillation of artificial tears was effective in preventing the effects of computer use on the ocular surface in post-LASIK patients.

Perioperative intense pulsed light to prevent and improve symptoms of post-laser corneal refractive surgery dry eye. A randomized clinical trial.

PURPOSE: To evaluate the efficacy of perioperative IPL therapy in preventing postoperative ocular surface disorders in patients undergoing corneal laser refractive surgery. DESIGN: randomized, controlled, clinical trial with triple-blinding. METHODS: Setting: Vissum Miranza - Alicante; Study population: 61 patients randomized in two groups: 31 study patients (perioperative IPL + laser refractive surgery) and 30 control patients (perioperative placebo + laser refractive surgery). Follow-up was conducted over a 6-month period; Intervention: Each participants underwent three IPL sessions with a two-week interval between each session (pre-surgery, post-surgery week-one, and post-surgery week-three). For controls, placebo was administered following the same protocol. MAIN OUTCOMES MEASURES: visual outcomes and refraction, slit-lamp examination, corneal topography, visual analogue scale questionnaire and Oculus Keratograph 5 M including tear meniscus height, non-invasive tear break- up time, ocular redness, infrared meibography and Ocular Surface Disease Index (OSDI) questionnaire. RESULTS: 61 randomized eyes were included. No significant differences were observed in terms of uncorrected and corrected distance visual acuity (UDVA, CDVA), refractive error or corneal aberrations. A statistically significant improvement in OSDI score (change -8.47, p = 0.043), tear meniscus (change 0.05 mm, p = 0.004) and Meibography (change -0.42, p = 0.012) was observed at the third postoperative month in the study group. Additionally, at the sixth postoperative month, there were statistically significant improvements in tear meniscus (change 0.06 mm, p = 0.018), tear break-up-time (change 1.68 s, p = 0.039) and Meibography (change -0.37, p = 0.030). CONCLUSIONS: Results suggest that perioperative IPL therapy applied to laser corneal refractive surgery improves objective and subjective ocular surface parameters over non-IPL-treated control patients and early postoperative dry eye symptoms.

Clinical outcomes of SMILE and WFG-LASIK used to treat myopia and astigmatism: A systematic review and meta-analysis.

PURPOSE: To evaluate the safety, efficacy and postoperative visual quality of small incision lenticule extraction (SMILE) and Wavefront-Guided Laser in situ keratomileusis (WFG-LASIK) and to analyze their efficacy in correcting astigmatism. METHODS: A systematic literature search was performed using Cochrane Collaboration methodology. Databases searched included PubMed, Embase, the Cochrane Library and Web of Science. RevMan software version 5.3.0 was used for meta-analysis. RESULTS: A total of 976 eyes were included in 8 studies, of which 539 eyes underwent SMILE and 437 eyes underwent WFG-LASIK. There were no statistically significant differences in the proportion of eyes achieving uncorrected distance visual acuity of 20/20 or better (P=0.18), the proportion of eyes within±0.50 diopter of target refraction postoperatively (P=0.10), or the postoperative magnitude of cylinder (P=0.10). Regarding the Alpins vector analysis of astigmatism, there was no statistically significant difference in the surgical magnitude of error (P=0.09) between the two groups. WFG-LASIK has a lower surgical angle of error (P= 0.002) and higher surgical correction index of cylinder (P=0.03) than SMILE. In terms of aberrations, higher order aberrations (P=0.46), spherical aberrations (P=0.22) and trefoil (P=0.56) were not statistically different, while WFG-LASIK induced less coma than SMILE surgery (P=0.02). CONCLUSION: Both SMILE and WFG-LASIK are safe and effective ways to correct myopia and astigmatism. Compared with SMILE, WFG-LASIK has a lower surgical angle of error, higher surgical correction index of cylinder and induces less coma.

Comparison of early changes in tear film protein profiles after small incision lenticule extraction (SMILE) and femtosecond LASIK (FS-LASIK) surgery.

BACKGROUND: Small incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (LASIK) are widely used surgical methods to correct myopia with comparable efficacy, predictability, and safety. We examined and compared the early changes of tear protein profiles after SMILE and FS-LASIK surgery in order to find possible differences in the initial corneal healing process. METHODS: SMILE operations for 26 eyes were made with Visumax femtosecond laser. In FS-LASIK surgery for 30 eyes, the flaps were made with Ziemer FEMTO LDV Z6 femtosecond laser and stromal ablation with Wavelight EX500 excimer laser. Tear samples were collected preoperatively, and 1.5 h and 1 month postoperatively using glass microcapillary tubes. Tear protein identification and quantification were performed with sequential window acquisition of all theoretical fragment ion spectra mass spectrometry (SWATH-MS). RESULTS: Immediately (1.5 h) after we found differences in 89 proteins after SMILE and in 123 after FS-LASIK operation compared to preoperative protein levels. Of these differentially expressed proteins, 48 proteins were common for both surgery types. There were, however, quantitative differences between SMILE and FS-LASIK. Upregulated proteins were mostly connected to inflammatory response and migration of the cells connected to immune system. One month after the operation protein expressions levels were returned to baseline levels with both surgical methods. CONCLUSIONS: Our study showed that immediate changes in protein profiles after SMILE and FS-LASIK surgeries and differences between the methods are connected to inflammatory process, and the protein levels quickly return to the baseline within 1 month. The differences in protein profiles between the methods are probably associated with the different size of the epithelial wound induced.

Impact of removing soft contact lenses 1 day versus 1 month before surgery on the outcomes of microkeratome laser in situ keratomileusis.

PURPOSE: To compare the outcomes, safety, efficacy, and predictability of microkeratome laser in situ keratomileusis (LASIK) 24 h and one month or more after removing soft contact lenses. SETTING: ULTRALASIK Eye Center, Dubai, United Arab Emirates. METHODS: The patients were divided based on the time of discontinuation of the soft contact lenses before LASIK (Group 1 at 24 h and Group 2 at one month or longer), and the two groups were well matched. Schirmer's testing, tear break-up time, corrected distance visual acuity, uncorrected distance visual acuity, manifest refraction spherical equivalent, and infection rate were evaluated preoperatively and at one week, one month, and six months after treatment. RESULTS: Group 1 (G1) comprised 1025 eyes, and group 2 (G2) had 1052 eyes. The groups were comparable preoperatively. The overall-mentioned outcomes were comparable between groups with uncorrected distance visual acuity of - 0.084 ± 0.12 logMAR in G1 and - 0.078 ± 0.17 logMAR in the G2 at 6 months (P = 0.322). Tear break-up time as well as Schirmer's testing results was also comparable with no evidence of increased risk of dry eyes or non-inflammatory complications in any of the groups on follow-up visits at 1 week (P = 0.421), 1 month (P = 0.101), and 6 months (P = 0.399) postoperatively. Finally, no infectious complications were recorded in either of the groups. CONCLUSION: With the absence of corneal warpage, no statistical or clinical difference in microkeratome LASIK outcomes and safety was spotted between the groups despite the difference in SCL discontinuation time before the procedure.

Achromobacter xylosoxidans keratitis in a LASIK flap treated with intrastromal antibiotics: a case report.

Intrastromal antibiotic injections are a type of treatment that can be very useful in bacterial keratitis refractory to topical antibiotics. We present the case of a 44-year-old woman with an infiltrate in a laser in situ keratomiuleusis (LASIK) flap and growth of Achromobacter xylosoxidans, who was treated with topical ceftazidime for 1 month. However, after discontinuation of the antibiotic, there was a worsening with growth of the same germ. Topical treatment was reintroduced and, due to suspicion of germ reservoir, it was decided to give three cycles of intrastromal ceftazidime injections, the last one also with moxifloxacin, with good results. After 4 months asymptomatic and without treatment at the moment, no signs of recurrence have been observed. This case supports the usefulness of intraestromal injections in refractory cases to the topical medication.

[Changes in accommodation in children with hyperopic anisometropia and unilateral amblyopia after laser refractive surgery and pleoptic treatment]. / Izmenenie akkomodatsii u detei s gipermetropicheskoi anizometropiei i odnostoronnei ambliopiei posle refraktsionno-lazernoi operatsii i pleopticheskogo lecheniya.

PURPOSE: This study comparatively analyzes the state of accommodation in children with hyperopic anisometropia and amblyopia after femtosecond laser-assisted in situ keratomileusis (Femto-LASIK) combined with pleoptic treatment, and after conventional pleoptic treatment. MATERIAL AND METHODS: The first group consisted of 30 children with medium and high hyperopia, high and medium amblyopia, and anisometropia greater than 3.0 diopters, who underwent Femto-LASIK in the amblyopic eye. The second group consisted of 28 children with similar local status, who were prescribed traditional correction and received conservative treatment. The follow-up period was 1.5 years. RESULTS: After 1.5 years, higher visual acuity (p<0.05) was achieved in the first group. A significant increase in the coefficient of accommodative response (CAR) was observed in the operated amblyopic eyes in group 1 - by 0.1±0.02 c.u. compared to the control group (p<0.05). In both groups there was an upwards trend for the coefficient of microfluctuations (CMF) in the amblyopic eye, but in the first group CMF increased more significantly (p<0.05). The objective accommodative response (OAR) and positive relative accommodation (PRA) of the amblyopic eye showed a double increase - by 1.0±0.23 and 0.9±0.38 diopters, respectively, at the end of treatment in the first group. The increase in similar indicators in the second group was insignificant (p<0.05). In children of the first group the difference in ciliary muscle thickness (CMT) of the amblyopic eye with disabled and enabled accommodation increased by 0.04±0.01 mm (p<0.05) in the anterior part of the ciliary muscle at the levels of CMTmax and CMT1. CONCLUSION: The data obtained in this study indicate the strong effect of refractive laser surgery in combination with pleoptic treatment on improving the visual acuity and the state of accommodation of the amblyopic and paired dominant eyes in children with hyperopic anisometropia, in contrast to conventional methods of treatment.

Toxicidad por marcador corneal en Femto-LASIK. Reporte de caso / Toxicity by corneal marker in Femto-LASIK. Case report

La violeta de genciana es un colorante orgánico sintético, descrito por primera vez por Charles Lauth en 1861. Tiene propiedades antibacterianas, antifúngicas, antihelmínticas, antitripanosómicas, antiantiogénicas y antitumorales. Tiene diversos mecanismos de acción, entre los que principalmente se encuentra bloquear la actividad de las nicotinamida adenina dinucleótido fosfato oxidasas, evitando la generación de radicales superoxidativos y la posterior inflamación. En los últimos años se ha utilizado en marcadores para procedimientos en diferentes especialidades médicas, incluidos los de oftalmología. La tinta de violeta de genciana se describe por el fabricante como no tóxica, sin embargo existe evidencia clínica y experimental que sugiere que puede ser tóxica para el endotelio corneal y puede llegar a generar queratitis lamelar difusa posterior a LASIK y Femto-LASIK. Se describe el caso de una paciente de 23 años de edad, que presentó diversas patologías en la córnea después del uso de marcador quirúrgico durante procedimiento refractivo Femto-LASIK.

Gentian violet is a synthetic and organic dye. First described by Charles Lauth in 1861. It has antibacterial, antifungal, anthelmintic, antitrypanosomal, antiangiogenic, and antitumoral properties. It has various mechanisms of action, among which is mainly blocking the activity of nicotinamide adenine dinucleotide phosphate oxidases, preventing the generation of superoxidative radicals and subsequent inflammation. In recent years, it has been used as markers for procedures in different medical specialties, including ophthalmology. Gentian violet ink is described by the manufacturer as non-toxic, however, there is clinical and experimental evidence suggesting that it may be toxic to the corneal endothelium and may cause diffuse lamellar keratitis after LASIK and Femto-LASIK. The case about a 23-year-old female patient who presented various pathologies in the cornea after the use of a surgical marker during the Femto-LASIK refractive procedure is described.