Bilateral Myopic Laser In Situ Keratomileusis Research Articles

Does Pregnancy Affect Refractive and Corneal Stability or Corneal Epithelial Remodeling After Myopic LASIK?

To investigate possible refractive changes in pregnant women who have previously undergone myopic laser in situ keratomileusis (LASIK). This prospective study included 64 pregnant women (128 eyes) who had previously undergone bilateral myopic LASIK. Uncorrected distance visual acuity (UDVA), spherical equivalent, corneal keratometry, topography and tomography, and epithelial mapping were evaluated before LASIK, 12 months after LASIK, during the third trimester of pregnancy, and 1 year postpartum. The average age at the time of recruitment was 32.5 ± 5 years (range: 24.5 to 39.5 years). The evaluation during pregnancy was at an average 55 months (range: 12 to 108 months) from the initial LASIK procedure. The preoperative mean refractive error was -6.72 ± 2.96 diopters (D) (range: -1.00 to -11.00 D). Comparing 12-month refractive data after the original LASIK procedure to the those within the third trimester of the subsequent pregnancy, the average UDVA was 20/18, the residual refractive error was -0.63 ± 1.00 to -0.51 ± 0.82 D, the steepest keratometry value was 40.85 ± 1.89 to 40.88 ± 2.84 D, and the central epithelial thickness was 56.4 ± 3.89 to 57.38 ± 5.04 µm, respectively. In this study, pregnancy did not affect the refractive stability of LASIK. Pregnancy-related changes in refractive error, corneal stability, and total corneal and epithelial thickness in women after LASIK were not found to be statistically significant. [J Refract Surg. 2022;36(2):118-122.].

Safety and efficacy of a hydrogel inlay with laser in situ keratomileusis to improve vision in myopic presbyopic patients: One-year results

To study the safety and efficacy of implanting a hydrogel corneal inlay (Raindrop Near Vision Inlay) concurrently with performing laser in situ keratomileusis (LASIK) to treat myopic presbyopia and to compare the results with results of the same treatment in emmetropic and hyperopic patients. Two private clinics, Tijuana and Monterrey, Mexico. Prospective nonrandomized clinical trial. Bilateral myopic LASIK was performed and a corneal inlay was concurrently implanted in the nondominant eye under a flap created using a femtosecond laser. Primary safety outcomes were the retention of corrected distance (CDVA) and near (CNVA) visual acuities. Efficacy was evaluated on the basis of uncorrected near (UNVA), intermediate (UIVA), and distance (UDVA) visual acuities. A patient questionnaire was used to assess the preoperative and postoperative incidence of visual symptoms, the ability to perform common tasks with no correction, and patient satisfaction with vision. Thirty eyes were enrolled. At each postoperative visit, the mean CDVA and CNVA were within one half line of preoperative measurements and no eye lost 2 or more lines of CDVA. The mean binocular UDVA, UIVA, and UNVA were better than 20/25 Snellen at all postoperative visits. By 6months, 93% of patients had a binocular Snellen acuity of 20/25 or better across all visual ranges. According to patient questionnaires, 1year after surgery, visual symptoms were at preoperative levels, 98% of all visual tasks could be easily performed without correction, and 90% of patients were satisfied or very satisfied with their overall vision. A hydrogel corneal inlay with concurrent LASIK was safe and effective for treating myopic presbyopia. Drs. Garza and Chayet are consultants to and investigators for Revision Optics, Inc.

In vivo confocal laser microscopy of morphologic changes after simultaneous LASIK and accelerated collagen crosslinking for myopia: One-year results

To evaluate the safety of corneal collagen crosslinking (CXL) combined with laser in situ keratomileusis (LASIK). Shinagawa LASIK Center, Tokyo, Japan. Case series. Bilateral myopic LASIK patients had unilateral accelerated CXL (KXL System) in the nondominant eye. After LASIK, riboflavin 0.1% was instilled in the residual stromal bed for 60 seconds. After the riboflavin was washed out and the flap placed in its original position, ultraviolet-A light (30 mW/cm(2)) was administered for 60 seconds. The LASIK-CXL eyes and the LASIK-only eyes were compared. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, manifest refraction spherical equivalent (MRSE), keratometry values, endothelial cell density (ECD), pachymetry, optical coherence tomography (OCT), corneal hysteresis (CH), corneal resistance factor (CRF), keratoconus match index (KMI), and 37 parameters from a dynamic bidirectional applanation device (Ocular Response Analyzer) were analyzed. Morphologic changes were evaluated using confocal microscopy. No significant differences in UDVA, CDVA, MRSE, ECD, dynamic bidirectional applanation readings (eg, CH, CRF, KMI), or 37 additional parameters were found between the 2 groups (P>.05). Increased hyperreflectivity and a demarcation line similar to that seen after CXL were observed in the LASIK-CXL eyes. The demarcation line (mean depth 200.04 μm ± 27.01 [SD]; range 178 to 278 μm) was present in 23 eyes (95.8%); the line was well defined in 2 eyes (8.3%) and faint in 21 eyes (87.5%). Combined LASIK-CXL was safe, causing insignificant corneal biomechanical and morphologic changes similar to those with CXL treatment only. No author has a financial or proprietary interest in any material or method mentioned.

Visual Outcomes of LASIK-Induced Monovision in Myopic Patients With Presbyopia

To evaluate binocular visual acuity (VA), contrast sensitivity, and stereopsis in myopic patients after laser in situ keratomileusis (LASIK)-induced monovision. Prospective, observational study. We performed a prospective study of 37 consecutive patients older than 45 years who underwent bilateral myopic LASIK with planned monovision. At the 6-month postoperative visit, we evaluated distance and near binocular visual acuity, contrast sensitivity, and stereopsis. Binocular tests were done without spectacles (in monovision condition) and compared with the results obtained by repeating the same binocular tests with the same patients (serving as a control group) after spectacle correction of the residual myopic defect in the nondominant eye for distance tests (reverting monovision) and after spectacle correction of the presbyopia bilaterally for near tests (near best spectacle-corrected VA). By inducing a mean residual spherical equivalent defect of -0.97 diopter in the nondominant eye, the patients achieved a mean near binocular uncorrected visual acuity (UCVA) of 0.74, a mean reading test binocular UCVA of 0.88 using an acceptable spontaneous reading distance (48 cm), and a mean distance binocular UCVA of 1.08. A slight decrease in contrast sensitivity and stereopsis was observed in monovision compared to full distance correction. Monovision is a valid option for myopic patients with presbyopia who are considering LASIK. Good distance and near UCVAs can be obtained with this procedure.

Dry eyes and corneal sensation after laser in situ keratomileusis with femtosecond laser flap creation: Effect of hinge position, hinge angle, and flap thickness

To determine whether corneal sensation and dry-eye signs and symptoms after myopic laser in situ keratomileusis (LASIK) surgery with a femtosecond laser are affected by varying hinge position, hinge angle, or flap thickness. University-based academic practice, Ann Arbor, Michigan, USA. This prospective randomized contralateral-eye study evaluated eyes after bilateral myopic LASIK with a femtosecond laser (IntraLase). Superior and temporal hinge positions, 45-degree and 90-degree hinge angles, and 100 microm and 130 microm corneal flap thicknesses were compared. Postoperative follow-up at 1 week and 1, 3, 6, and 12 months included central Cochet-Bonnet esthesiometry, the Ocular Surface Disease Index questionnaire, a Schirmer test with anesthesia, tear breakup time (TBUT), corneal fluorescein staining, and conjunctival lissamine green staining. The study evaluated 190 consecutive eyes (95 patients). Corneal sensation was reduced at all postoperative visits, with improvement over 12 months (P<.001). There was no difference in corneal sensation between the different hinge positions, angles, or flap thicknesses at any time point. The overall ocular surface disease index score was increased at 1 week, 1 month, and 3 months (P<.0001, P<.0001, and P = .046, respectively). The percentage of patients with a TBUT longer than 10 seconds was significantly lower at 1 week and 1 month (P<.0001). Dry-eye syndrome after myopic LASIK with a femtosecond laser was mild and improved after 3 months. Corneal flap hinge position, hinge angle, and thickness had no effect on corneal sensation or dry-eye syndrome.

Effect of hinge position on corneal sensation and dry eye after laser in situ keratomileusis using a femtosecond laser

To determine whether hinge position has an effect on corneal sensation and dry-eye symptoms after myopic laser in situ keratomileusis (LASIK) performed with the IntraLase femtosecond laser (IntraLase Corp.). University-based academic practice, Ann Arbor, Michigan, USA. Sixty-six consecutive eyes of 33 patients were prospectively evaluated in a randomized contralateral-eye study to compare the difference between superior-hinge and temporal-hinge locations after bilateral myopic LASIK with the IntraLase femtosecond laser. Central Cochet-Bonnet esthesiometry, the Ocular Surface Disease Index (OSDI) questionnaire, Schirmer test with anesthesia, tear breakup time (TBUT), corneal fluorescein, and conjunctival lissamine green staining were evaluated preoperatively as well as 1 week and 1, 3, 6, and 12 months after surgery. Corneal sensation was reduced with both superior-hinged and temporal-hinged LASIK flaps 1 week and 1, 3, 6, and 12 months after surgery (P<.0001). There was no difference in corneal sensation between superior-hinged and temporal-hinged flaps at any time point. The OSDI score was increased in 22.6% of patients at 1 week and 21.9% at 1 month (P<.00001), and corneal fluorescein staining was increased in 18% at 1 week. There were no differences in the OSDI, Schirmer with anesthesia, TBUT, corneal fluorescein, or conjunctival lissamine green staining when preoperative values and hinge location were compared. Mild dry-eye disease was present early after myopic LASIK with the IntraLase laser. Hinge position had no effect on central corneal sensation or dry-eye disease.

Outcome of LASIK in Fleck Corneal Dystrophy

To report the outcome of laser in situ keratomileusis (LASIK) in a patient with Fleck corneal dystrophy. Case report and literature review. A 48-year-old Taiwanese man presented in November 2005, 6 years after bilateral myopic LASIK. He complained of loss of uncorrected distance visual acuity that was worse in the left eye. The patient did not report glare, halos, or other visual aberrations. Preoperative best spectacle-corrected visual acuity (BSCVA) was 20/25 OU, with a manifest refraction of -14 D OU. In November 2005, uncorrected visual acuity (UCVA) was 20/40 OD and 20/50 OS, and BSCVA was 20/25 in each eye with a manifest refraction of -1.00 sphere OD and -1.75 -1.25 x 115 OS. Slit-lamp examination was remarkable for several subtle, small, gray corneal opacities present throughout the corneal stroma. Confocal microscopy revealed refractile bodies within swollen keratocytes and normal surrounding stromal mileu. The clinical and confocal appearance was consistent with Fleck corneal dystrophy. In this patient with Fleck corneal dystrophy, corneal clarity and BSCVA were maintained 6 years after bilateral myopic LASIK, suggesting that LASIK does not stimulate visually significant exacerbation of Fleck corneal dystrophy.

Effect of hinge location on corneal sensation and dry eye after laser in situ keratomileusis for myopia

To evaluate the effects of a superior or nasal hinge location on corneal sensation and dry eye after laser in situ keratomileusis (LASIK). Magill Research Center for Vision Correction, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. This prospective randomized masked study included 47 patients having bilateral myopic LASIK surgery. The first eye was randomly assigned to have a nasal or superior hinge flap; the fellow eye had the alternate location. Visual acuity, contrast sensitivity, corneal sensation, basic secretion test, tear film breakup time, conjunctival and corneal staining, and a subjective questionnaire were evaluated preoperatively and postoperatively at 1 week and 1, 3, and 6 months. The Wilcoxon signed rank test and paired t test were used for comparison. Dry eye occurred with the same frequency in both groups. However, eyes with the nasal hinge had significantly better nasal sensation than those with the superior hinge (P<.05) at 1 month. Better nasal corneal sensation was found at 1 month in the nasal hinge group but there was no difference in any other parameters measured.

Lacrimal Gland-Associated Immune Deviation in the Rat

To determine whether hinge position has an effect on corneal sensation and dry-eye symptoms after myopic laser in situ keratomileusis (LASIK) performed with the IntraLase femtosecond laser (IntraLase Corp.).University-based academic practice, Ann Arbor, Michigan, USA.Sixty-six consecutive eyes of 33 patients were prospectively evaluated in a randomized contralateral-eye study to compare the difference between superior-hinge and temporal-hinge locations after bilateral myopic LASIK with the IntraLase femtosecond laser. Central Cochet-Bonnet esthesiometry, the Ocular Surface Disease Index (OSDI) questionnaire, Schirmer test with anesthesia, tear breakup time (TBUT), corneal fluorescein, and conjunctival lissamine green staining were evaluated preoperatively as well as 1 week and 1, 3, 6, and 12 months after surgery.Corneal sensation was reduced with both superior-hinged and temporal-hinged LASIK flaps 1 week and 1, 3, 6, and 12 months after surgery (P<.0001). There was no difference in corneal sensation between superior-hinged and temporal-hinged flaps at any time point. The OSDI score was increased in 22.6% of patients at 1 week and 21.9% at 1 month (P<.00001), and corneal fluorescein staining was increased in 18% at 1 week. There were no differences in the OSDI, Schirmer with anesthesia, TBUT, corneal fluorescein, or conjunctival lissamine green staining when preoperative values and hinge location were compared.Mild dry-eye disease was present early after myopic LASIK with the IntraLase laser. Hinge position had no effect on central corneal sensation or dry-eye disease.

Simultaneous bilateral laser in situ keratomileusis: Safety and efficacy

Objective To compare the safety and efficacy of simultaneous bilateral to sequential bilateral laser in situ keratomileusis (LASIK) surgery for the correction of myopia. Design Retrospective, nonrandomized, comparative trial. Participants A total of 2142 consecutive simultaneous and sequential bilateral myopic LASIK surgery eyes operated from March 1996 through June 1998 for the correction of myopia were reviewed. Intervention Two surgeons (HVG and JAV) performed myopic LASIK using the Nidek EC-5000 excimer laser and either the Chiron Automated Corneal Shaper or the Bausch & Lomb Hansatome microkeratome. Main outcome measures The incidence of intra- or perioperative complications for sequential and simultaneous bilateral LASIK for myopia was recorded. Refractive and visual outcomes at 3 to 6 months postoperative were analyzed. Deviations from targeted spherical equivalent (SE), uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), and retreatment rates are reported. Results Laser in situ keratomileusis was performed on the first eye of 1853 patients scheduled for simultaneous bilateral myopic LASIK. Of these, 28 (1.5%) first eyes had intraoperative or perioperative complications. The second eye surgery was cancelled in 11 cases, and 1842 second eyes completed simultaneous surgery; 13 (0.7%) intraoperative or perioperative complications occurred. Of these 41 complications in simultaneous cases, 1 eye lost 1 line of BCVA at 6 months follow-up. Two hundred eighty-nine patients were scheduled for sequential bilateral myopic LASIK. Five (1.8%) first eyes of the sequential cases had intraoperative complications compared with four (1.4%) sequential second eyes. There was no loss of BCVA in any sequential bilateral case with complications at a minimum at 6 months follow-up. There was no statistically significant difference between intra- and perioperative complication rates comparing simultaneous to sequential bilateral LASIK. Three to 6 months postoperative visual and refractive data were reviewed; except when comparing simultaneous first eye postoperative SE to sequential first eye, there was no statistically significant difference in refractive or visual outcomes, including deviation from targeted SE, UCVA, BCVA, and retreatment rates. Conclusion Simultaneous bilateral LASIK is as safe and effective as sequential surgery. Simultaneous bilateral LASIK may offer several benefits to the patient.