Samuel Levinger

Single Intacs segment for post-laser in situ keratomileusis keratectasia

Purpose: To describe the visual outcome of implantation of a single Intacs® segment (Addition Technology Inc.) in eyes with keratectasia after myopic laser in situ keratomileusis (LASIK). Setting: Private refractive surgery center, Jerusalem, Israel. Methods: This retrospective, noncomparative, interventional, consecutive, small case series studied 5 eyes of 5 patients with post‐LASIK keratectasia from 3 refractive laser centers treated by Intacs implantation. Before and 9 months after Intacs implantation, the uncorrected visual acuity (UCVA), best spectacle‐corrected visual acuity (BSCVA), manifest refraction, keratometry, videokeratography, inferior−superior asymmetry, and patient questionnaires about visual function were assessed. Results: Intacs implantation was performed 17 to 32 months post LASIK with no intraoperative complications and no loss of visual acuity. After implantation, the UCVA improved 8, 4, 3, 0.5, and 5 lines and the BSCVA, 2, 2.5, 1, 0.5, and 2 lines. The mean manifest refraction spherical equivalent improved from −1.60 diopters (D) ± 1.67 (SD) to −0.80 ± 1.05 D. The mean manifest astigmatic correction decreased from −3.9 ± 2.96 to −2.46 ± 2.77 D. Corneal topography showed improved inferior steepening and less irregular astigmatism. The mean inferior−superior asymmetry improved from 7.88 ± 4.59 to 2.46 ± 2.77 D. Selfreported visual symptoms improved significantly in Cases 1, 2, and 5 and slightly in Cases 3 and 4. Conclusions: Implantation of a single Intacs segment inferiorly appeared to improve progressive myopia and regular and irregular astigmatism in eyes with corneal ectasia after LASIK. With further study, this technique may prove to be an effective, relatively noninvasive approach.

Intacs adjustment surgery for keratoconus

PURPOSE: To describe the visual outcome of keratoconic eyes managed with Intacs (Addition Technology, Inc.) that required additional Intacs surgery (defined as any combination of removal, exchange, addition, or shifting of an Intacs segment). SETTING: Private refractive surgery center, Jerusalem, Israel. METHODS: This retrospective noncomparative interventional consecutive small case series studied all eyes of a cohort of 58 keratoconic eyes managed with Intacs that had additional Intacs surgery. The uncorrected visual acuity (UCVA), best spectacle‐corrected visual acuity, manifest refraction, videokeratography, and patient questionnaires on visual function were assessed. These outcome measures were compared before Intacs implantation, before Intacs adjustment, and 1 year after the final Intacs adjustment. Eyes having any intervention other than Intacs surgery were excluded. RESULTS: Of 58 keratoconic eyes managed with Intacs, 7 had additional Intacs surgery. After the initial Intacs surgery, 6 of these eyes had UCVA ≤20/100 and 1 had UCVA of 20/50. After the final Intacs adjustment, 3 eyes achieved UCVA ≥20/40, 5 achieved UCVA ≥20/70, and 2 remained <20/200. The indications for Intacs adjustments were increased astigmatism in 4 eyes, induced hyperopia (overcorrection) in 3, and undercorrection in 1. One eye had both surgically induced astigmatism and hyperopia. Induced astigmatism and hyperopia were most often managed by removing the superior segment. The undercorrected eye, having initially received a single inferior segment, was treated by implanting a superior segment. CONCLUSIONS: Approximately 10% of keratoconic eyes managed with Intacs may require Intacs adjustment surgery, which often has a good outcome.

Monovision surgery in myopic presbyopes: visual function and satisfaction.

Purpose To describe our experience with monovision excimer laser correction in individuals with myopic presbyopia. Methods This prospective interventional case series was conducted in a private refractive surgery center on 40 patients with presbyopia aged 40 years and older, who were treated with monovision refractive surgery between 2010 and 2011. The dominant eye was corrected for distance vision and the nondominant eye was corrected for near vision, with anisometropia of ≥1.00 diopters (D). All patients underwent comprehensive objective and subjective visual assessments, including a questionnaire that was filled out preoperatively and at 6 and 12 months postoperatively. The primary outcomes were preoperative and postoperative refraction, binocular visual acuity, stereopsis, contrast sensitivity, glare, and questionnaire results. Results The 1-year follow-up was completed by 38 patients (95%). Preoperative and 1-year postoperative refraction of the distance eye spherical equivalent (SE), anisometropia SE, and uncorrected visual acuity were −4.05 ± 1.94 and −0.01 ± 0.22 D, 0.45 ± 0.50 and 1.73 ± 0.56 D, and 0.87 ± 0.2 and 0.09 ± 0.11 logMAR, respectively. Best-corrected visual acuity was unchanged. Both mean distance and near stereopsis decreased, from 52 to 142 seconds of arc and from 54 to 57 seconds of arc, respectively. Contrast sensitivity and glare decreased significantly. Patient satisfaction improved from 41.5 ± 30.4% to 85.2 ± 5.0% (range, 40 to 100%) at the 1-year follow-up. Conclusions Monovision excimer laser correction provides both effective and satisfactory results and should be considered as an option for individuals with myopic presbyopia suitable for, and interested in, refractive surgery.

Wiping microkeratome blades with sterile 100% alcohol to prevent diffuse lamellar keratitis after laser in situ keratomileusis

Purpose: To report our experience in preventing diffuse lamellar keratitis (DLK) after laser in situ keratomileusis (LASIK) by wiping the microkeratome blade with sterile 100% alcohol. Setting: Enaim Refractive Surgery Center, Jerusalem, Israel. Methods: Laser in situ keratomileusis was performed in 24 patients (48 eyes) on the same day by the same surgeon. The environment and instruments were identical in all cases. A new blade was used in both eyes of each patient. All blades were from the same batch and were randomly assigned to 2 groups. In the alcohol group, 12 blades were wiped with a Merocel® surgical spear (Medtronic Solan) dipped in 100% alcohol and rinsed with balanced salt solution (BSS®) before they were mounted in a Hansatome® microkeratome (Bausch & Lomb Co.); in the control group, 12 blades were wiped with a Merocel surgical spear dipped in BSS and rinsed with BSS. All patients were examined on the first postoperative day. Results: Grade I to II DLK was diagnosed in 7 eyes of 4 patients in the control group (29%). No DLK was diagnosed in the alcohol group. Conclusion: Wiping the microkeratome blade with 100% alcohol before mounting may remove a substance from the manufacturing or sterilization process that can cause DLK.

Toxic anterior segment syndrome following iris-supported phakic IOL implantation with viscoelastic Multivisc BD.

Purpose. To report on the association between Multivisc BD and toxic anterior segment syndrome (TASS) post phakic intraocular lens (IOL) implantation. Methods. Two patients developed severe toxic anterior chamber inflammation following implantation of phakic iris fixated IOL with Multivisc BD viscoelastic. Anterior chamber washout was performed with intracameral antibiotic injection. Local antibiotics were continued until cultures were found to be negative. Thereafter, intensive local and systemic steroids were initiated and gradually tapered down. Results. The inflammatory reaction disappeared completely and the visual acuity improved from hand motion to 6/9 without correction within 1 week. Conclusions. Any viscoelastic material may be contaminated by heat-stable bacterial endotoxic as it is prepared by gene-coded bacteria. It is suggested that Multivisc BD was the etiologic factor of TASS. Refractive surgeons should be aware of this rare complication of phakic IOL implantation whenever they use a new viscoelastic material.

Laser in situ Keratomileusis for Correction of Myopia in Eyes After Retinal Detachment Surgery

PURPOSE To evaluate the safety and efficacy of laser in situ keratomileusis (LASIK) for correction of myopia in eyes with previous retinal detachment surgery. METHODS A retrospective review was conducted of all consecutive eyes that underwent LASIK after retinal detachment surgery. Data was collected regarding previous ocular surgery and its time prior to LASIK, intra- and postoperative complications, and visual outcome measures pre- and postoperatively. RESULTS Ten eyes with previous retinal detachment surgery were scheduled for LASIK. One eye was excluded from data analysis as LASIK was aborted due to inadequate microkeratome suction because of conjunctival scarring. Nine eyes underwent an uneventful LASIK procedure. On average, LASIK was performed 130+/-123 months following retinal detachment surgery. Postoperative LASIK follow-up was 14.8+/-12.5 months. No significant intraoperative, postoperative, or retinal complications were observed. The mean preoperative spherical equivalent refraction was -9.00+/-3.00 diopters (D), uncorrected visual acuity (UCVA) was 0.06+/-0.02, and best spectacle-corrected visual acuity (BSCVA) was 0.64+/-0.16. At the end of follow-up, the mean spherical equivalent refraction was 0.65+/-0.88 D, mean UCVA was 0.57+/-0.14, and mean BSCVA was 0.72+/-0.19. Differences between BSCVA before and after LASIK were statistically significant (P=.038). At final follow-up, the safety index was 1.22 and efficacy index was 1.01. CONCLUSIONS Laser in situ keratomileusis was found to be a safe and efficient option for treating refractive errors in eyes with previous retinal detachment surgery.

Bioptics for high hyperopia with combined multifocal intraocular lens implantation and excimer ablation in young patients

Purpose: To analyze the visual and refractive outcome of the bioptics procedure combining multifocal intraocular lens implantation and excimer laser surgery in young patients with high hyperopic eyes not suitable for a single surgical procedure. Methods: This retrospective case series included 10 eyes of five patients (age range 18–30 years) with high hyperopia (spherical equivalent +8.51 ± 0.85 diopters (D)). They had been treated with serial multifocal intraocular lens implantation followed 6 weeks later by laser in situ keratomileusis for residual hyperopia. Uncorrected distance visual acuity, uncorrected near visual acuity, corrected distance visual acuity, corrected near visual acuity, and manifest refraction were evaluated before surgeries, after multifocal intraocular lens implantation, and 3 months post laser in situ keratomileusis. Results: No patients were lost to follow-up (6 months). The mean spherical equivalent decreased to +2.05 ± 1.33 D after multifocal intraocular lens implantation and to −0.10 ± 0.58 D after the laser in situ keratomileusis procedure. Success of the procedures was determined by uncorrected visual acuity. LogMAR uncorrected distance visual acuity improved by a total of more than six lines from 1.05 ± 0.18 LogMAR to 0.46 ± 0.12 LogMAR post multifocal intraocular lens implantation and to 0.15 ± 0.06 LogMAR after both surgeries. The LogMAR uncorrected near visual acuity increased by 0.81 ± 0.82 LogMAR after lens implantation due to loss of accommodation, and all eyes reached a LogMAR of 0 at 1 month postoperatively following laser in situ keratomileusis. Conclusions: A bioptics approach involving multifocal intraocular lens followed 6 weeks later by a laser in situ keratomileusis procedure for the correction of very high hyperopia enabled the resolution of the residual refractive error in young very high hyperopic patients.

Air-pulse corneal applanation signal curve parameters for characterization of astigmatic corneas.

Purpose: The aim of this study was to test the 42 parameters of the ocular response analyzer for distinguishing between the biomechanical properties of emmetropic eyes with normal topography and eyes with moderate-to-high with-the-rule astigmatism (WTA) and against-the-rule astigmatism (ATA) that have symmetric bowtie topography. Methods: This retrospective case series study included 37 patients (37 studied eyes) with WTA astigmatism and 35 patients (35 studied eyes) with ATA astigmatism. The control group consisted of 70 patients with emmetropia (70 studied eyes) with normal topography. We first tested correlations of the parameters that describe the applanation curve during ocular response analyzer measurements with the maximum keratometry values and the corneal thickness in all 3 groups. We then evaluated the significant parameters among them in search of any group differences in the biomechanical properties of the cornea. Results: Fifteen parameters correlated with Kmax reading values or corneal thickness values. The correlation coefficients (r) were low. The best correlated parameters were p1area, p2area, h1, dive1, p2area1, h11, h2, and h21. The ATA group had the highest number of parameters (n = 6) with significant differences compared with the control group. Only p2area was predictive for ATA. In contrast, the WTA group had only 1 parameter (p2area1) that was found to be significantly different compared with the control group. Conclusions: Some of the new waveform parameters can distinguish between patients with ATA and WTA and normal topography patterns and may delineate the differences in biomechanical properties between these groups that may predict the risk of corneal ectasia after laser in situ keratomileusis.