Comparison of laser in situ keratomileusis reoperation outcomes with the Moria M2 head 90 and 130 following previous photorefractive keratectomy or laser in situ keratomileusis

Purpose: To compare the Moria Model Two (M2) automated microkeratome with the head 90 (intended to create a 120‐μm flap) to the head 130 (intended to create a 160‐μm flap) in reoperations following previous photorefractive keratectomy (PRK) or laser‐assisted in situ keratomileusis (LASIK) in terms of accuracy, predictability, safety and complications of the procedure. Methods: Eighty‐five eyes of 70 consecutive patients received LASIK with the Moria M2 microkeratome. Nine previously PRK‐operated eyes were reoperated with the head 90 and 37 eyes were reoperated with the head 130. Repeated LASIK was performed on 16 eyes with the head 90 and on 23 eyes with head the 130. Flap dimensions were measured and correlated to preoperative parameters. Results: The average flap thickness in the previously PRK‐operated eyes was 115.1 μm [range 82–137 μm, standard deviation (SD) 17.9] with the head 90 and 131.2 μm (range 105–171 μm, SD 19.8) with the head 130. In the previously LASIK‐operated eyes, the mean flap thickness was 139.2 μm (range 92–182 μm, SD 23.8) with the head 90 and 141.9 μm (range 109–179 μm, SD 15.2) with the head 130. There were no free or incomplete flaps or flaps with buttonholes in the study. There was no statistically significant difference in postoperative uncorrected visual acuity (UCVA) between the groups. Conclusion: In eyes with previous PRK or LASIK, LASIK reoperation offers a safe alternative for improving refractive outcomes. The Moria M2 head 90, especially in LASIK‐operated eyes, does not cut thinner flaps compared to the head 130.     

Thin flap laser in situ keratomileusis: flap dimensions with the Moria LSK-One manual microkeratome using the 100-microm head

PURPOSE: To determine the predictability and consistency of corneal flap thickness, flap diameter, and hinge length with the modern 100 microm head of the Moria LSK-One manual microkeratome. SETTING: Private clinic, office-based practice. METHODS: Forty-two consecutive eyes with no previous surgery having thin flap laser in situ keratomileusis with the Moria LSK-One manual microkeratome had a new 100 microm (predicted flap thickness) head used for flap creation. Flap thickness was measured intraoperatively by subtraction ultrasound pachymetry (difference between central corneal thickness before flap cutting and residual stromal bed thickness after flap lifting). Vertical flap diameter and nasal hinge length were measured with calipers. RESULTS: Mean flap thickness was 107 microm +/- 14 (SD) (range 82 to 137 microm). Standard deviation for mean vertical flap diameter was +/-0.24 mm. The cord length of the nasal hinge was variable with a mean of 4.26 +/- 0.63 mm (range 3.12 to 5.75 mm) in length. Postoperatively, there were no slipped flaps, flap striae, diffuse lamellar keratitis, or epithelial defects; there was 1 epithelial slide. At 1 day, the visual acuity was 20/20 or better in 76% of eyes. CONCLUSIONS: The 100 microm head of the Moria LSK-One manual microkeratome cut a very predictable flap thickness and diameter but with variable length hinges. This flap thickness predictability was superior to that in other series with thicker intended flaps cut with mechanical microkeratomes and is comparable to that reported with the IntraLase FS femtosecond laser. Visual recovery was rapid, epithelial risks minimal, efficiency superior, and cost nominal relative to femtosecond laser technology.     

Influence of flap thickness on results of laser in situ keratomileusis for myopia

PURPOSE: To study whether flap thickness influences laser in situ keratomileusis (LASIK) results. METHODS: This comparative, non-randomized, retrospective study comprised 421 LASIK eyes (233 patients) with spherical equivalent refraction between -0.60 and -6.00 diopters (D). Laser in situ keratomileusis was performed with the Moria One manual microkeratome and the Chiron Technolas 217C laser. Depending on the flap thickness, the eyes were divided into three groups (group 1, flap thickness < or =100 microm; group 2, flap thickness > 100 microm and < 130 microm; and group 3, flap thickness > or = 130 pm). For each group uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity, residual spherical equivalent refraction, and keratometric power (D) were measured 1 day, 1 week, 1 month, and 6 months after LASIK. Complications, retreatment, and correlation between flap thickness and preoperative corneal thickness and keratometric power were also analyzed. RESULTS: One month postoperatively, UCVA was > or = 20/20 in 76% (96 eyes), 56% (79 eyes), and 61% (93 eyes) of eyes in the three group, respectively (P = .015). One month postoperatively, UCVA was > or = 20/25 in 88% (111 eyes), 76% (108 eyes), and 76% (116 eyes) of eyes in the three groups, respectively (P = .015). Complication rate and retreatment rate were not statistically different among the groups. At 6-month follow-up, no statistically significant differences were noted in UCVA between the groups. Significant correlations between flap thickness and preoperative corneal thickness (P < .0001) and between flap thickness and preoperative keratometric power (P < .05) were found. CONCLUSION: Patients with flaps < or = 100 pm had better functional results at 1 month than those with thicker flaps. It may be important to perform LASIK with thin flaps to save corneal tissue in the stromal bed.     

Femtosecond laser in situ keratomileusis after radial keratotomy

PURPOSE: To assess the safety, efficacy, and predictability of femtosecond laser in situ keratomileusis (LASIK) in eyes with previous radial keratotomy (RK). SETTING: Hospital Virgen del Consuelo de Valencia, Valencia, and Vissum Instituto Oftalmológico de Alicante, Alicante, Spain. METHODS: This prospective study comprised 11 eyes of 7 patients with residual low myopia after previous RK who had surgery with the IntraLase femtosecond laser (IntraLase Corp.) and the Star 2 excimer laser (Visx, Inc.). Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), defocus equivalent, refraction, flap thickness, flap diameter, and intraoperative complications were evaluated over a minimum 6-month follow-up. RESULTS: Although the RK incisions opened in all eyes when the flap was lifted, LASIK was successfully completed in all cases. Mean flap thickness was 119 microm +/- 13 (SD). There were no cases of slipped flaps, microstriae, or epithelial ingrowth. Defocus equivalent was reduced from a mean of 2.51 +/- 0.62 diopters (D) to 0.52 +/- 0.28 D; 7 eyes (63.6%) were within +/-0.50 D, and 11 eyes (100%) were within +/-1.00 D. All eyes had 20/40 or better UCVA, although 2 eyes (18.1%) lost 1 line of BSCVA. CONCLUSIONS: The femtosecond laser was safely used to create thin LASIK flaps in eyes with previous RK. An increased postoperative inflammatory response may explain the loss of BSCVA in some cases. Efficacy and predictability of the procedure were comparable to those of LASIK after RK with mechanical microkeratomes.     

LASIK flap characteristics using the Moria M2 microkeratome with the 90-microm single use head

PURPOSE: To evaluate the accuracy and consistency of corneal flap thickness, horizontal diameter, and hinge size with the Moria M2 90-microm single use head. METHODS: Fifty-two myopic patients (104 eyes), mean age 32.6 years, underwent bilateral LASIK with a superior hinged flap using the Moria M2 microkeratome (90-microm single use head). Prospective evaluation included flap thickness (subtraction method), diameter, hinge size, interface particles, intraoperative complications, and visual recovery. RESULTS: The mean preoperative spherical equivalent refraction was -5.72 +/- 2.59 diopters (D) (range: -2.88 to -10.75 D) and -5.84 +/- 2.73 D (range: -3.13 to -9.38 D) for right and left eyes, respectively. The mean preoperative central corneal thickness was 548 +/- 24 microm and 547 +/- 25 microm for right and left eyes, respectively. The mean preoperative steepest K was 44.12 +/- 1.28 D and 44.41 +/- 1.27 D for right and left eyes, respectively. Corneal diameter (white-to-white) was 12 +/- 0.4 mm and 11.9 +/- 0.4 mm for right and left eyes, respectively. The mean postoperative flap thickness was 109 +/- 18 microm (range: 67 to 152 microm) and 103 +/- 15 microm (range: 65 to 151 microm) for right and left eyes, respectively. The mean postoperative flap diameter was 9.4 +/- 0.3 mm (expected mean according to the nomogram given by the company was 9.5 mm). The mean postoperative hinge chord was 4.4 +/- 0.4 mm (expected mean 4.2 mm). No interface particles were detected on slit-lamp examination. CONCLUSIONS: The Moria M2 90-microm single use head is safe with reasonable predictability for LASIK flap creation.     

Corneal flap measurements in laser in situ keratomileusis using the Moria M2 automated microkeratome

PURPOSE: To evaluate accuracy and predictability and factors that influence the dimensions of the laser in situ keratomileusis (LASIK) corneal flap created with the Moria M2 automated microkeratome (Moria SA, Antony, France). METHODS: The flap thickness of 454 eyes of 243 consecutive patients was measured using subtraction ultrasonic pachymetry during LASIK with the Moria M2 microkeratome head 130 designed to create a 160-microm-thick flap. Flap dimensions were evaluated and measurements were correlated with preoperative parameters. A stepwise regression analysis was used to determine the factors that influenced actual flap thickness. RESULTS: The preoperative spherical equivalent refraction of the 454 eyes ranged from -12.125 diopters (D) to +6.25 D. Patient age ranged from 18 to 57 years (mean age: 31.3 +/- 8.8 years). Mean preoperative keratometric power K1 was 44.31 +/- 1.59 D and K2 was 43.32 +/- 1.54 D. Mean preoperative central comeal thickness was 552.4 +/- 32.5 microm (range: 466 to 665 microm). With an attempted thickness of 160 microm, the Moria M2 flap thickness ranged from 77 to 209 microm (mean: 153.3 +/- 19.0 microm). Mean horizontal flap diameter was 9.2 +/- 0.2 mm and mean hinge length 4.6 +/- 0.3 mm. Increasing flap thickness was found to correlate with increasing preoperative comeal thickness, younger patient age, and flatter preoperative keratometric power K1. CONCLUSIONS: Although the standard deviation of the flap thickness was relatively small, remarkable individual variation was noted. Therefore, the intraoperative calculation of the remaining stromal bed is recommended. Furthermore, the consideration of central corneal thickness, patient age, and preoperative keratometry are helpful parameters to avoid too deep ablation.     

Corneal flap thickness in laser in situ keratomileusis using the Moria M2 microkeratome

PURPOSE: To determine the predictability of flap thickness in laser in situ keratomileusis (LASIK) using the Moria M2 microkeratome and identify factors that may be related to variations in flap thickness. SETTING: Laser Vision Correction Center, Bascom Palmer Eye Institute, University of Miami School of Medicine, Miami, Florida, USA. METHODS: Charts of 208 patients having same-day bilateral LASIK using the Moria M2 microkeratome were reviewed. Intraoperative pachymetry was performed routinely. The right eye was always treated first. The same suction ring, stop, microkeratome head (110 microm or 130 microm), and blade were used in fellow eyes. Subtraction pachymetry was used to calculate flap thickness. Other collected data included age, keratometry, corneal diameter, and preoperative spherical equivalent (SE). RESULTS: With the 110 microm head and slow translation velocity in both eyes, the mean flap thickness was 151.6 microm +/- 24.0 (SD) and 148.5 +/- 24.3 microm in the right and left eyes, respectively. With the 110 microm head and fast translation velocity in both eyes, the mean thickness was 136.2 +/- 25.5 microm and 132.8 +/- 23.5 microm, respectively. With the 130 microm head and fast translation velocity, the mean flap thickness was 145.8 +/- 25.4 microm and 139.9 +/- 25.5 microm, respectively. Flaps were thinner with fast translation velocity, the 110 microm head, and presumably duller blades used in the left eyes. There was a weak but statistically significant inverse correlation between flap thickness and age and between flap thickness and SE. A stronger correlation was found in flap thickness between right and left eyes. CONCLUSIONS: Flap thickness with the Moria M2 microkeratome was variable. Fast translation velocity, a used (presumably duller) blade, and the 110 microm head produced thinner flaps. Given the potential variation in flap thickness (SD 23.5 to 25.5 microm), intraoperative pachymetry might be an adjunctive measure to prevent residual stromal beds that are thinner than planned, especially in patients with high myopia and/or thin corneas.     

Laser in situ keratomileusus for mixed and simple myopic astigmatism with the Nidek EC-5000 Laser

PURPOSE: To evaluate the visual and refractive results of laser in situ keratomileusis (LASIK) for mixed and simple myopic astigmatism using bitoric ablation. METHODS: A retrospective study was performed in 65 eyes of 38 consecutive patients to evaluate uncorrected (UCVA) and best spectacle-corrected visual acuity (BSCVA) and cyclopegic and manifest refraction, before and 3 and 6 months after LASIK (Moria LSK-ONE microkeratome, Nidek EC-5000 excimer laser). RESULTS: At 3 and 6 months after LASIK, 40 eyes of 24 patients (64.5%) were available for follow-up examination. Mean age was 25.9 +/- 6.6 years (range 18 to 43 yr). Mean preoperative manifest spherical equivalent refraction was -1.40 +/- 0.80 D (range -3.80 to +0.50 D) mean preoperative cylinder was -3.30 +/- 1.30 D (range -1.00 to -6.00 D). At 6 months follow-up, mean manifest spherical equivalent refraction was +0.30 +/- 0.46 D (range -0.38 to +1.88 D), mean cylinder was -0.73 +/- 0.61 D (range -2.25 to 0 D). There was a 77.8% decrease in astigmatism magnitude. According to vector analysis, mean achieved vector magnitude was 80% of intended. Fifty percent (20 eyes) had a cylinder within +/- 0.50 D of emmetropia. Twenty-three eyes (57.5%) had a spherical component within +/- 0.50 D. Eighty-five percent (34 eyes) had postoperative UCVA of 20/40 or better. Ten percent (four eyes) lost two lines of Snellen BSCVA, whereas 35% (14 eyes) gained one or more lines. CONCLUSIONS: Bitoric LASIK with the Moria LSK-ONE microkeratome and Nidek EC-5000 excimer laser was effective and safe for the reduction of cylinder in mixed and simple myopic astigmatism. Moderate undercorrection of the cylinder was evident.     

Long-term results of superficial laser in situ keratomileusis after ultrathin flap creation

PURPOSE: To study the long-term efficacy, safety, and stability of laser in situ keratomileusis (LASIK) after unintentional ultrathin flap creation less than 80 mum. SETTING: University refractive surgery center. METHODS: This retrospective case series comprised 25 patients (33 eyes) who had LASIK after flap creation less than 80 mum with the Moria M2 disposable microkeratome (head 90 microm). Flap thickness was measured with intraoperative ultrasound pachymetry. Manifest refraction, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity, predictability, stability, complications, patient satisfaction, and confocal microscopy images were studied. RESULTS: The mean follow-up was 14.58 months +/- 3.73 (SD) (range 12 to 25 months). The mean flap thickness was 72.1 +/- 5.9 microm (range 58 to 80 microm), and the mean preoperative spherical equivalent (SE) refraction was -5.59 +/- 2.01 diopters (D) (range -10.25 to -3.25 D). On the first postoperative day, the UCVA was 20/25 or better. The SE manifest refraction was 1.00 D or less in all patients. The mean SE manifest refraction was -0.75 +/- 0.55 D (range -1.00 to +0.75 D) (P < .01). At the last follow-up, changes in visual acuity and manifest refraction were not statistically significant; no late postoperative complications were observed. All patients were satisfied with the final outcome. Qualitative analysis of confocal microscopy images revealed interface particles and activated keratocytes. CONCLUSIONS: Despite the small sample and retrospective nature of the study, superficial LASIK seemed to be a safe and predictable technique for myopic refractive corrections. Patients were satisfied with the results and had rapid visual recovery with no intraoperative or early or late postoperative complications. If the safety and efficacy of an ultrathin flap are confirmed by additional studies, superficial LASIK could represent a new approach that combines the advantages of surface and lamellar procedures.     

Laser in situ keratomileusis for hyperopia and hyperopic astigmatism with the Nidek EC-5000 Excimer laser.

PURPOSE: We evaluated the efficacy, predictability, stability, and safety of laser in situ keratomileusis (LASIK) for hyperopia and hyperopic astigmatism. METHODS: A retrospective study was performed for 92 eyes of 62 consecutive patients to evaluate uncorrected (UCVA) and best spectacle-corrected visual acuity (BSCVA) and manifest refraction before and 3 and 6 months after LASIK (Moria LSK-ONE microkeratome, Nidek EC-5000 excimer laser). Eyes were divided into groups: Group 1 (low hyperopia) for spherical correction of +1.00 to +3.00 D (22 eyes), Group 2 (low hyperopic astigmatism) for toric correction with spherical equivalent refraction of +1.00 to +3.00 D (18 eyes), Group 3 (moderate hyperopia) for spherical correction of +3.25 to +6.00 D (10 eyes), and Group 4 (moderate hyperopic astigmatism) for toric correction with spherical equivalent refraction between +3.25 and +6.00 D (18 eyes). RESULTS: At 3 and 6 months after LASIK, 68 eyes (73.9%) were available for follow-up examination. Percentage of eyes with a spherical equivalent refraction within +/-0.50 D of emmetropia for Group 1 was 54.5% (12 eyes); Group 2, 50% (9 eyes); Group 3, 40% (4 eyes), and Group 4, 38.8% (7 eyes). UCVA > or =20/20 in Group 1 was 14% and in Groups 2, 3, and 4, 0%. One eye (5.5%) lost two lines of BSCVA. CONCLUSION: LASIK with the Moria LSK-ONE microkeratome and the Nidek EC-5000 excimer laser reduced low and moderate hyperopia and was within +/-0.50 D of target outcome in approximately 50% of eyes. Undercorrection was evident in all groups. The procedure was safe.     

Comparison of flap thickness reproducibility using microkeratomes with a second motor for advancement

PURPOSE: To compare flap thickness and reproducibility of four different types of microkeratomes during LASIK. DESIGN: Retrospective, nonrandomized, comparative case series. PARTICIPANTS: Four hundred ninety consecutive eyes underwent LASIK and were evaluated by measuring the central flap thickness by subtractive pachymetry. METHODS: All flaps were created using the Bausch & Lomb (Miami, FL) Hansatome 180 head, the Alcon (Fort Worth, TX) Summit Krumeich Barraquer Microkeratome 160 head, the Moria (Antony, France) Carriazo Barraquer (CB) 130 head, or the Moria M2 110 head. RESULTS: The flap thickness measurements differed according to the microkeratome used and were 131+/-28 microm in 41 eyes (8.4%) with the Bausch & Lomb Hansatome 180 head, 162+/-21 microm in 127 eyes (25.9%) with the Alcon Summit Krumeich Barraquer Microkeratome (SKBM) 160 head, 157+/-40 microm in 65 eyes (13.3%) with the Moria CB 130 head, and 134+/-23 microm in 257 eyes (52.4%) with the Moria M2 110 head. The central flap thickness with the SKBM and Moria M2 was statistically significantly more reproducible than with the Moria CB (P< 0.0005). There is no correlation between flap thickness reproducibility and age, corneal thickness, or corneal keratometric values. However, considering all the microkeratomes, female gender had statistically significantly more variability than male gender (P<0.02). CONCLUSIONS: Based on these results, the greatest predictability of flap thickness was seen with the SKBM and Moria M2 microkeratomes, which both use a second motor for advancement. The greatest variability, noted with the Moria CB, was likely due to the manual translation feature and places further importance on the safety of the second motor and automation when performing LASIK.     

Femtosecond laser in situ keratomileusis for consecutive hyperopia after radial keratotomy

PURPOSE: To assess the use of the femtosecond laser for laser in situ keratomileusis (LASIK) in eyes with consecutive hyperopia after radial keratotomy (RK). SETTING: Private ambulatory surgical center, Valencia, Spain. METHODS: This prospective noncomparative interventional case series study included 13 eyes of 9 patients with secondary hyperopia after previous RK. The patients were operated on with the IntraLase femtosecond laser (IntraLase Corp.) and the Star S2 excimer laser (Visx, Inc.). Postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest refraction, flap thickness, flap diameter, and complications were evaluated at 6 months. RESULTS: The mean spherical equivalent (SE) decreased from 2.00 diopters (D)+/-0.40 (SD) to -0.41+/-0.61 D, with 8 eyes (61.5%) within+/-0.50 D of the targeted refraction. Twelve eyes (92.3%) had a UCVA of 20/40 or better, and 3 eyes (23.1%) lost 1 line of BSCVA. A mean change in SE of 0.10 D was observed at the 6-month follow-up. The mean flap thickness and diameter were 117+/-14 microm and 9.18+/-0.12 mm, respectively. Most complications were in eyes with more than 8 RK incisions than in eyes with 8 RK incisions. These complications were multiple intraoperative incision openings (100% versus 28.6%, respectively), interface inflammation (66.6% versus 0%, respectively), haze (83.3% versus 14.3%, respectively), and loss of BSCVA (50% versus 0%, respectively). CONCLUSIONS: The femtosecond laser provided large, thin corneal flaps for hyperopic LASIK. However, the procedure should be avoided in eyes with more than 8 RK incisions because of the increased risk for multiple intraoperative incision openings, interface inflammation, haze, and loss of BSCVA.     

Comparison of the IntraLase femtosecond laser and mechanical keratomes for laser in situ keratomileusis

PURPOSE: To compare laser in situ keratomileusis (LASIK) results obtained with the femtosecond laser (IntraLase Corp.) to those obtained using 2 popular mechanical microkeratomes. SETTING: Private practice, Greensboro, North Carolina, USA. METHODS: This retrospective analysis compared LASIK outcomes with the femtosecond laser to those with the Carriazo-Barraquer (CB) microkeratome (Moria, Inc.) and the Hansatome microkeratome (Bausch & Lomb, Inc.). The 3 groups were matched for enrollment criteria and were operated on under similar conditions by the same surgeon. RESULTS: There were 106 eyes in the IntraLase group, 126 eyes in the CB group, and 143 eyes in the Hansatome group. One day postoperatively, the uncorrected visual acuity (UCVA) results in the 3 groups were similar; at 3 months, the UCVA and the best spectacle-corrected visual acuity results were not significantly different. A manifest spheroequivalent of +/-0.50 diopter (D) was achieved in 91% of eyes in the IntraLase group, 73% of eyes in the CB group, and 74% of eyes in the Hansatome group (P<.01). IntraLase flaps were significantly thinner (P<.01) and varied less in thickness (P<.01) than flaps created with the other devices. The mean flap thickness was 114 microm +/- 14 (SD) with the IntraLase programmed for a 130 microm depth, 153 +/- 26 microm with the CB using a 130 microm plate, and 156 +/- 29 microm with the Hansatome using a 180 microm plate. Loose epithelium was encountered in 9.6% of eyes in the CB group and 7.7% of eyes in the Hansatome group but in no eye in the IntraLase group (P =.001). Surgically induced astigmatism in sphere corrections was significantly less with the IntraLase than with the other devices (P<.01). CONCLUSIONS: The IntraLase demonstrated more predictable flap thickness, better astigmatic neutrality, and decreased epithelial injury than 2 popular mechanical microkeratomes.     

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.     

Randomized comparison of custom laser in situ keratomileusis with the Alcon CustomCornea and the Bausch & Lomb Zyoptix systems: one-month results

PURPOSE: To compare the early visual results of custom laser in situ keratomileusis (LASIK) outcomes for two different excimer laser systems. METHODS: This is a preliminary report of an ongoing prospective study that evaluated 30 patients (60 eyes) who were randomized to one of two custom LASIK treatment groups: 15 patients (30 eyes) with the Alcon CustomCornea laser system (Alcon Laboratories Inc, Fort Worth, Tex) and 15 patients (30 eyes) with the Bausch & Lomb Zyoptix laser system (Bausch & Lomb, Rochester, NY). These matched patients were required to qualify for treatment with both custom laser systems. All flaps were created with the IntraLase femtosecond laser (IntraLase Corp, Irvine, Calif) using a superior hinge. Early outcome measures are uncorrected visual acuity (UCVA) at 1 day, 1 week, and 1 month postoperative; manifest refractions at 1-month follow-up; and a comparison of 1-month postoperative UCVA to preoperative best spectacle-corrected visual acuity (BSCVA). Wavefront, topography, contrast sensitivity, and subjective questionnaires were also performed and will be reported after 3-month follow-up. RESULTS: At 1 month, the percentage of eyes with UCVA of 20/20 and 20/40 were similar with 93% and 100%, respectively, for CustomCornea eyes and 90% and 97%, respectively, for Zyoptix eyes. A difference between the two groups is in the percentage of eyes with UCVA of 20/16, 20/12.5, and 20/10 with 80%, 47%, and 13%, respectively, for CustomCornea and 70%, 10%, and 0%, respectively, for Zyoptix. The mean residual spherical equivalent refraction was +0.01 +/- 0.34 diopters (D) for CustomCornea and -0.04 +/- 0.38 D for Zyoptix. The two groups are similar at +/-1.00 D of intended correction, with CustomCornea 100% and Zyoptix 97%. However, +/-0.25 D the CustomCornea group was 10% more accurate at 73% versus 63% for the Zyoptix group. The efficiency ratio (postoperative UCVA compared to preoperative BSCVA) was greater for the CustomCornea group at 20/20, 20/16,20/12.5, and 20/10 levels. CONCLUSION: Custom LASIK with CustomCornea and Zyoptix is safe and effective and produces excellent early visual outcomes. This study demonstrates that current standard metrics for reporting refractive surgery visual outcomes are not adequate for evaluating wavefront-guided laser vision correction procedures. Amending the standard reporting metrics to include visual outcomes at the 20/16, 20/12.5, and 20/10 levels; accuracy at the +/-0.25 D of attempted; and postoperative UCVA compared to preoperative BSCVA will improve our ability to analyze wavefront-guided outcomes.     

Laser in situ keratomileusis for residual hyperopic astigmatism after conductive keratoplasty

PURPOSE: To report a case of laser in situ keratomileusis (LASIK) in a patient with previous conductive keratoplasty. METHODS: A 48-year-old man underwent conductive keratoplasty for low hyperopic astigmatism (manifest refraction OD: +2.25 -0.50 x 77 degrees; OS: +2.50 -0.50 x 105 degrees). Three months postoperatively, UCVA was 20/25 and BSCVA was 20/20 in both eyes; manifest refraction OD: -0.25 -0.75 x 110 degrees; OS: +0.75 -0.75 x 50 degrees. Sixteen months after the operation, regression of refractive outcome was (manifest) OD: +1.75 -1.25 x 90 degrees; OS: +2.50 -0.50 x 85 degrees; UCVA was 20/40 in the right eye and 20/63 in the left eye and BSCVA was 20/20 in both eyes. LASIK was performed for hyperopic regression in the left eye using an automated microkeratome (Alcon SKBM, 130-microm plate; Aesculap-Meditec MEL 70 excimer laser). RESULTS: LASIK was uneventful and no intraoperative or postoperative complications related to the previous conductive keratoplasty procedure or LASIK were observed. Three months after LASIK and 19 months after the initial conductive keratoplasty, the patient's left eye was emmetropic; UCVA was 20/20(-2), BSCVA was 20/20 and manifest refraction was +0.25 -0.25 x 35 degrees. There was a uniform increase in topographical steepening. Visual acuity, refraction and topographic findings remained unchanged at 6 months. CONCLUSIONS: Even though our experience is limited, treatment of hyperopia with LASIK in an eye with refractive regression following previous conductive keratoplasty resulted in a predicted refractive outcome, with no complications, and improvement in visual acuity at 6 months follow-up.     

Transepithelial phototherapeutic keratectomy/photorefractive keratectomy with adjunctive mitomycin-C for complicated LASIK flaps

PURPOSE: To evaluate the efficacy of transepithelial phototherapeutic keratectomy/photorefractive keratectomy (PTK/PRK) with prophylactic mitomycin-C for the treatment of refractive errors and maintenance of corneal clarity following flap complications in laser in situ keratomileusis (LASIK). SETTING: Outpatient tertiary care center, Chicago, Illinois, USA. METHODS: Ten eyes of 10 patients with LASIK flap complications had transepithelial PTK/PRK for correction of ametropia. Mitomycin-C 0.02% was applied to the stroma for 2 minutes following laser ablation. Postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), refractions, and slitlamp examinations were obtained. RESULTS: Preoperatively, the mean UCVA was 20/400 (range 20/40 to counting fingers), the mean BSCVA was 20/28.5, and the spherical equivalent refractive errors ranged from +4.00 to -10.75 diopters (D). After the procedure, the mean UCVA was 20/28, the mean BSCVA was 20/21, and the spherical equivalent refractive errors ranged from +0.37 to -1.00 D. The mean follow-up ranged from 8 to 28 months. No patient experienced delayed reepithelialization, haze, or other signs of toxicity. CONCLUSION: Mitomycin-C can be a useful adjunctive therapy for the prevention of haze when applying surface excimer laser therapy to a cornea following LASIK flap complications.     

Moria M2微型角膜刀用常规刀片及Med—Logics 0号刀片制作LASIK角膜瓣的评估

背景角膜瓣的制作是准分子激光角膜原位磨镶术（LASIK）成功的关键步骤之一,随着微型角膜刀刀片技术的不断发展,其制作角膜瓣的精确性、均一性以及重现性已引起临床医师的广泛关注。目的比较MoriaM2微型角膜刀110刀头应用Med—Logics 0号刀片（110—0）及常规刀片（110）制作LASIK角膜瓣的特点。方法前瞻性研究。对近视患者102例204眼行LASIK,其中MoriaM2微型角膜刀110刀头应用Med—Logics0号刀片组（110—0组）及常规刀片组（110组）制作角膜瓣的患者各51例102眼。术后1周,应用RTVue傅里叶光学相干断层扫描（OCT）分别测量2组患者每个角膜上0°、45°、90°和135° 4条子午线所在截面上特定7个点的角膜瓣厚度,并对每个角膜瓣上28个测量点的角膜瓣厚度值进行对比分析。结果术后1周,110—0组和110组间裸眼视力和残余等效球镜度的差异均无统计学意义（视力：Z=-0．375,P=0．708;球镜度：u=0．056,P=0．956）。110—0组全角膜厚度为（133．28±15．41）μm,明显低于110组的（142．81±10．07）μm,差异有统计学意义（u=-5．227,P〈0．01）,并且110—0组与Moria公司提供的角膜瓣预期厚度值130μm更接近。2组制作的角膜瓣均为中间薄、周边厚,形状近似一凹透镜,并且2组右眼鼻侧和颞侧角膜瓣厚度比较差异均无统计学意义（P〉0．05）;左眼鼻侧均明显厚于颞侧,差异均有统计学意义（P〈0．05）。110—0组与110组角膜瓣厚度值与预计厚度130μm的差值分别为（17．46±2．28）μm和（16．82±6．12）μm,差异无统计学意义（u=0．517,P=0．608）。结论与110组比较,110—0组角膜瓣的厚度更薄,全角膜瓣厚度平均值与Moria公司提供的角膜瓣预期厚度值130μm更接近,其角膜瓣的均一性和预测性相对更好一些。     

Biomechanical effects of femtosecond and microkeratome-based flap creation: prospective contralateral examination of two patients

PURPOSE: To examine flap morphology, corneal topography, and aberrometry after flap creation with a femtosecond laser in one eye and a mechanical microkeratome in the fellow eye. Comparative outcomes after subsequent refractive laser correction were also investigated. METHODS: Two patients (4 eyes) were enrolled in a clinical study in which LASIK flaps were created using the IntraLase laser set at 90 or 100 microm in one eye and the Moria M2 microkeratome with a 90-microm head in the fellow eye. Pre- and postoperative flap data at 1 day, 1 week, and 1 month were collected before lifting the flap to perform a customized laser ablation (Alcon LADARVision4000 CustomCornea System). Postoperative laser data were collected at 1 week, 1 month, 3 and 6 months, and 1 year. Visual acuity, pachymetry, high-frequency flap ultrasound profilometry (Artemis Ultralink), topography, aberrometry (LADARWave), and refraction were examined and compared between eyes. RESULTS: Postoperative flap comparisons showed a hyperopic refractive shift in all four eyes with a shift of up to 1.00 diopter (D) in the microkeratome eyes and < 0.50 D in the IntraLase eyes. Corneal topography difference maps showed peripheral steepening that was more pronounced in the microkeratome versus IntraLase eyes (2.00 D vs 0.50 to 1.00 D, respectively). Spherical aberration by wavefront variably increased by 50% to 100% in the microkeratome eyes and remained virtually unchanged in the IntraLase eyes. At 3-month postoperative laser treatment, visual acuity was 20/15 for both eyes in patient 1 and 20/15 in the right eye (IntraLase) and 20/25 in the left eye (microkeratome) in patient 2. Aberrometry revealed a two-fold greater level of higher order aberrations in microkeratome eyes than in IntraLase eyes throughout the postoperative laser period. CONCLUSIONS: Femtosecond laser and mechanical methods of flap creation lead to subtle biomechanically induced aberrations, which appear more prominent with the mechanical Moria M2 microkeratome in this small case study. Further study with a larger patient population is warranted to determine whether these differences are statistically significant.     

Hyperopic laser in situ keratomileusis to treat overcorrected myopic LASIK

PURPOSE: To evaluate the safety and efficacy of hyperopic laser in situ keratomileusis (LASIK) in treating hyperopia caused by overcorrected myopic LASIK and to evaluate a new technique to place the hyperopic treatment after lifting the initial myopic flap. SETTING: Open-access outpatient excimer laser surgical facility. METHODS: A retrospective analysis was performed of 54 eyes in 47 patients who had spherical hyperopic LASIK by 21 surgeons for the treatment of significant hyperopia after overcorrected LASIK for myopia. In 42 eyes, the initial LASIK flaps were lifted and in 12 eyes, new flaps were cut. The mean age of the 25 men (53%) and 22 women (47%) was 48.2 years +/- 8.4 (SD). Outcome measures included refractive error, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), and complications. The mean follow-up was 2.97 months. RESULTS: In eyes in which postoperative emmetropia was attempted (n = 45), the mean spherical equivalent improved from +1.21 +/- 0.49 diopters (D) preoperatively to -0.38 +/- 0.50 D postoperatively (P <.001). The mean UCVA improved from 20/38.6 +/- 16.3 to 20/27.4 +/- 9.4 (P <.001). At the last follow-up, 69% of eyes were within +/-0.5 D and 96% were within +/-1.0 D of emmetropia; 42% had a UCVA of 20/20 and 96% had a UCVA of 20/40 or better. No eyes lost 2 or more lines of BSCVA. No vision-threatening complications occurred. Results in patients who had initial flaps lifted and those who had new flaps cut were statistically indistinguishable. On average, achieved hyperopic corrections were 18% greater than intended. CONCLUSION: Hyperopic LASIK was safe, predictable, and effective in the treatment of hyperopia caused by overcorrected myopic LASIK. Results were similar whether the original flap was lifted or a new one was cut.