Acetazolamide-induced bilateral choroidal effusion following insertion of a phakic implantable collamer lens.

PURPOSE: To present the case of a 28-year-old man with acetazolamide-induced bilateral choroidal effusion after uneventful surgery of the second eye in delayed sequential bilateral insertion of an implantable collamer lens for hyperopia. METHODS: Case report. RESULTS: Surgery of the left eye was uneventful, and the implantable collamer lens was implanted 3 weeks later in the right eye. Twenty-four hours after surgery, the patient presented with bilateral shallow anterior chamber, vault 0, and myopic shift (-8 diopters) in both eyes. B-scan ultrasound showed choroidal thickening in both eyes, which was consistent with choroidal effusion syndrome. A causal relationship was suspected with oral acetazolamide, which had been prescribed after surgery. When the drug was stopped, the condition improved slowly and resolved completely within 5 days. CONCLUSIONS: Choroidal effusion should be included in the differential diagnosis of shallow anterior chamber after implantation of an implantable collamer lens.

Mesopic pupil size in a refractive surgery population (13,959 eyes).

PURPOSE: To evaluate factors that may affect mesopic pupil size in refractive surgery candidates. METHODS: Medical records of 13,959 eyes of 13,959 refractive surgery candidates were reviewed, and one eye per subject was selected randomly for statistical analysis. Detailed ophthalmological examination data were obtained from medical records. Preoperative measurements included uncorrected distance visual acuity, corrected distance visual acuity, manifest and cycloplegic refraction, topography, slit lamp examination, and funduscopy. Mesopic pupil size measurements were performed with Colvard pupillometer. Relationship between mesopic pupil size and age, gender, refractive state, average keratometry, and pachymetry (thinnest point) were analyzed by means of ANOVA (+ANCOVA) and multivariate regression analyses. RESULTS: Overall mesopic pupil size was 6.45 ± 0.82 mm, and mean age was 36.07 years. Mesopic pupil size was 5.96 ± 0.8 mm in hyperopic astigmatism, 6.36 ± 0.83 mm in high astigmatism, and 6.51 ± 0.8 mm in myopic astigmatism. The difference in mesopic pupil size between all refractive subgroups was statistically significant (p < 0.001). Age revealed the strongest correlation (r = -0.405, p < 0.001) with mesopic pupil size. Spherical equivalent showed a moderate correlation (r = -0.136), whereas keratometry (r = -0.064) and pachymetry (r = -0.057) had a weak correlation with mesopic pupil size. No statistically significant difference in mesopic pupil size was noted regarding gender and ocular side. The sum of all analyzed factors (age, refractive state, keratometry, and pachymetry) can only predict the expected pupil size in <20% (R = 0.179, p < 0.001). CONCLUSIONS: Our analysis confirmed that age and refractive state are determinative factors on mesopic pupil size. Average keratometry and minimal pachymetry exhibited a statistically significant, but clinically insignificant, impact on mesopic pupil size.

Trifocal intraocular lens implantation in eyes with previous corneal refractive surgery for myopia and hyperopia.

PURPOSE: To evaluate the visual and refractive outcomes of trifocal intraocular lens (IOL) implantation in eyes previously treated with myopic and hyperopic corneal refractive laser surgery. SETTING: Clinica Baviera-AIER-Eye group, Spain. DESIGN: Retrospective comparative case series. METHODS: The series was divided into 2 groups according to the type of corneal laser refraction (myopic and hyperopic). The main visual and refractive outcome measures included corrected distance visual acuity (CDVA) and uncorrected distance and near visual acuity, safety, efficacy, and predictability. The secondary outcome measures were percentage of enhancement and Nd:YAG capsulotomy and influence of prelaser magnitude of myopia and hyperopia on the outcome of trifocal IOL implantation. RESULTS: The sample comprised 868 eyes (543 patients): myopic, n = 319 eyes (36.7%); and hyperopic, n = 549 eyes (63.2%). Three months postoperatively, visual outcomes were poorer in the hyperopic group than those in the myopic group for mean CDVA (0.06 ± 0.05 vs 0.04 ± 0.04, P < .01) and safety (21% vs 12% of CDVA line loss, P < .05) outcomes. However, precision outcomes were worse in the myopic group than those in the hyperopic group, with a mean spherical equivalent of -0.38 ± 0.3 vs -0.17 ± 0.3 (P < .01). Stratification by magnitude of primary laser treatment revealed poorer visual and safety results in the high hyperopia subgroup (>+3.0 diopters [D]) and poorer precision in the high myopia subgroup (<-5.0 D). CONCLUSIONS: Trifocal IOL implantation after photorefractive surgery in eyes previously treated with myopic ablation achieved good visual outcomes but less predictability in the high myopia subgroup. However, eyes with a previous hyperopic corneal ablation achieved excellent precision but worse visual and safety outcomes in the high hyperopia subgroup.

Infectious keratitis in 204 586 LASIK procedures.

PURPOSE: To investigate the incidence, culture results, risk factors, and visual outcomes of infectious keratitis after LASIK, and examine treatment strategies. DESIGN: Retrospective study. PARTICIPANTS: We included 107 613 patients who underwent LASIK at Clínica Baviera (Instituto Oftalmológico Europeo, Spain) from September 2002 to May 2008. METHODS: The medical records of post-LASIK patients (204 586 eyes) were reviewed to identify cases of infectious keratitis. Incidence, risk factors, clinical course, days to diagnosis, medical and surgical treatment, and final visual outcomes were recorded. MAIN OUTCOME MEASURES: Incidence of post-LASIK infectious keratitis, culture results, response to treatment, and visual outcome. RESULTS: Post-LASIK infectious keratitis was diagnosed in 72 eyes from 63 patients. Onset of infection was early (within 7 days after surgery) in 62.5% of cases. Cultures were positive in 21 of 54 cases in which samples were taken. The most frequently isolated microorganism was Staphylococcus epidermidis (9 cases). Immediate flap lifting and irrigation with antibiotics was performed in 54 eyes; late flap lifting was subsequently required in 10 out of 18 cases initially treated with topical antibiotics alone. One case required flap amputation owing to flap necrosis. Final best spectacle-corrected visual acuity (BSCVA) was >or=20/20 in 38 cases (52.7%) and >or=20/40 in 67 cases (93.05%); final BSCVA was <20/40 in 5 cases (6.94%). CONCLUSIONS: The incidence of post-LASIK infectious keratitis was 0.035% per procedure. Infectious keratitis after LASIK is a potentially vision-threatening complication. The appearance of infections in asymptomatic patients highlights the need for a proper schedule of follow-up appointments. Prompt and aggressive management of this LASIK complication with early flap lifting, scraping, culture, and irrigation with antibiotics is strongly recommended. Proper management can result in preserving useful vision. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Dynamic Assessment of Light-Induced Vaulting Changes of Implantable Collamer Lens With Central Port by Swept-Source OCT: Pilot Study.

PURPOSE: To assess dynamic variations in vault induced by changes in brightness in eyes implanted with phakic collamer intraocular lens (pIOL) with central port for correction of myopia, defining new parameters of vaulting measurement. METHODS: We used a noninvasive Fourier-domain swept-source anterior-segment optical coherence tomography (AS-OCT) system to dynamically evaluate the shifts between the pIOL and anterior chamber structures under changing light conditions. For each eye assessed, we measured vault interval (VI), which we define based on central vault values in maximum mydriasis and in maximum miosis after light-induced changes in pupil diameter, and vault range (VR), which we define as the absolute difference between the VI values. RESULTS: The pilot study sample comprised 39 eyes (23 patients) previously implanted (mean 107 ± 156 days) with a pIOL. A significant difference in vault value was found when maximum and minimum pupil size was assessed under changing external light conditions (P < 0.001). The mean VR from scotopic (0.5 lux) to photopic (18,500 lux) light conditions was 167 ± 70 µm. CONCLUSIONS: Vault is continuously affected during movements of the pupil induced by external luminance. TRANSLATIONAL RELEVANCE: Quantifiable dynamic parameters VR and VI obtained with this AS-OCT device describe the position of the pIOL in the posterior chamber of the eye in a more accurate and real way than static vault measurements, and may contribute to improved understanding of the behavior of the pIOL in terms of safety.

Effect of preoperative keratometric power on intraoperative complications in LASIK in 34,099 eyes.

PURPOSE: To evaluate the effect of preoperative keratometric power on the intraoperative complications in LASIK for myopia, hyperopia, and astigmatism. METHODS: In this retrospective study, the records of 34,099 eyes of 17,388 patients who underwent LASIK for myopia, hyperopia, and astigmatism using the Moria LSK One manual microkeratome and the Bausch & Lomb Technolas 217 Z excimer laser were reviewed. RESULTS: One thousand three hundred thirty-eight (3.92%) intraoperative microkeratome complications were identified in the total number of eyes: 571 (1.67%) free caps, 320 (0.93%) epithelial abrasions, 282 (0.82%) thin/irregular flaps, 126 (0.36%) incomplete flaps, and 39 (0.11%) flap buttonholes. When eyes were stratified according to preoperative keratometric power, eyes with flatter corneas usually had more free caps and incomplete flaps than eyes with steeper corneas (P < .05), whereas eyes with steeper corneas usually had more epithelial abrasions and thin/irregular flaps than eyes with flatter corneas (P < .05). The risk of free caps, incomplete flaps, and epithelial abrasions was greater when bigger keratome rings (H) were used than when smaller rings (-1) were used (P < .05). The incidence of buttonholes was independent of the preoperative keratometric power, keratome plate (100 or 130 microm), and keratome ring (-1, -2, or H). CONCLUSIONS: No statistically significant relationship was found between preoperative keratometric power and incidence of flap buttonholes in this series. Eyes with flatter corneas tended to have more free caps and incomplete flaps, whereas eyes with steeper corneas tended to have more epithelial abrasions and thin/irregular flaps.

Laser in situ keratomileusis in patients with a history of ocular herpes.

PURPOSE: To report the outcomes of laser in situ keratomileusis (LASIK) in patients with a history of ocular herpes simplex virus (HSV) or herpes zoster ophthalmicus (HZO). SETTING: Clínica Baviera, Instituto Oftalmológico Europeo, Madrid, Spain. METHODS: In this retrospective case series, the records of eyes with a history of ocular herpes that had LASIK from 2003 through 2005 were reviewed. The main outcome measure was postoperative recurrence of ocular herpes. RESULTS: Forty-nine eyes (48 patients) with a history of ocular herpes (HSV keratitis, 28 eyes; HSV eyelid lesions, 17 eyes; HZO, 4 eyes) were identified. All LASIK procedures were uneventful. Herpetic disease was inactive at the time of surgery in all eyes and for more than 1 year in 31 eyes. Perioperative antiviral systemic prophylaxis was used in 13 patients with a history of HSV keratitis. No eye developed reactivation of herpetic keratitis during the follow-up (range 1 to 28 months). CONCLUSIONS: Laser in situ keratomileusis was safe in patients with a history of ocular herpes; no recurrences occurred during the follow-up period. However, candidates should be selected with caution and surgery performed only in eyes in which the herpes has been inactive for 1 year before surgery, without stromal disease, and with regular topography and pachymetry maps and normal corneal sensitivity. The most reasonable clinical strategy is perioperative systemic antiviral prophylaxis.

Visual Outcomes Following Bilateral lmplantation of Two Diffractive Trifocal Intraocular Lenses in 10 084 Eyes.

PURPOSE: To investigate refractive and visual acuity outcomes, patient satisfaction, and spectacle independence at 3 months of 2 diffractive (non-toric) trifocal intraocular lenses (IOLs) in a large series of patients. DESIGN: Multicenter, retrospective, nonrandomized clinical study. METHODS: Patients underwent lens phacoemulsification and were implanted bilaterally with a diffractive trifocal IOL: FineVision Micro F (PhysIOL SA, Liège, Belgium) or AT Lisa tri 839MP (Carl Zeiss AG, Jena, Germany). Surgeries were performed between 2011 and 2015 with at least 3 months of follow-up. Visual and refractive performance, patient satisfaction, and spectacle independence were evaluated. RESULTS: A total of 10 084 trifocal IOLs were bilaterally implanted (5802 FineVision in 2901 patients and 4282 AT Lisa in 2141 patients). Three-month mean (± standard deviation) acuity: AT Lisa, binocular uncorrected distance visual acuity (UDVA), -0.01 logMAR ± 0.06; monocular distance corrected visual acuity (CDVA), 0.02 logMAR ± 0.06; binocular uncorrected near visual acuity (UNVA) at 40 cm, 0.05 logMAR ± 0.08; binocular uncorrected intermediate visual acuity (UIVA) at 80 cm, -0.05 logMAR ± 0.14; postoperative spherical equivalent, 0.26 D ± 0.47; cylinder -0.34 D ± 0.38; FineVision Micro F, binocular UDVA, 0.01 logMAR ± 0.05; monocular CDVA, 0.03 logMAR ± 0.06; binocular UNVA, 0.05 logMAR ± 0.08; binocular UIVA, -0.05 logMAR ± 0.12; spherical equivalent, 0.34 D ± 0.50; cylinder -0.39 D ± 0.40. The IOLs were equivalent in achieving spectacle independence; 98% were "satisfied" to "very satisfied" with their IOL performance. CONCLUSIONS: In this retrospective study with over 5000 patients, implantation of both trifocal IOL models provided good functional distance, intermediate, and near visual acuity, resulting in high levels of both spectacle independence and patient satisfaction.

LASIK outcomes in patients with underlying systemic contraindications: a preliminary study.

OBJECTIVES: To determine the anatomic and functional outcomes of photorefractive surgery in patients with underlying systemic diseases that are traditionally listed as relative or absolute contraindications. DESIGN: Observational retrospective case-control study. PARTICIPANTS: The case groups were composed of 275 eyes of 141 consecutive patients who underwent a LASIK procedure with any of the following underlying conditions: autoimmune connective-tissue disorders (n = 62), psoriasis (n = 91), intestinal inflammatory diseases (n = 67), diabetes mellitus (n = 44), and history of keloid formation (n = 18). Twenty-nine patients (56 eyes) were receiving systemic immunosuppressive therapy. The control group comprised 358 eyes of 181 patients without the above-mentioned conditions who underwent LASIK. METHODS: The study had 2 parts, relating to the anatomic and functional (visual and refractive) outcomes. For anatomic outcome, we compared the entire sample of both groups. For functional outcome, only myopic eyes of each group were compared. Independent comparisons were performed between each disease group and the control group. MAIN OUTCOME MEASURES: Anatomic outcomes included perioperative and postoperative epithelial, flap, and interface complications. Functional outcomes were evaluated using visual and refractive indicators, percentage of eyes undergoing enhancement, and number of postoperative visits. RESULTS: Mild anatomic complications were observed in the case and control groups with similar percentages, and there were no statistical differences between groups. Regarding functional outcome, the only significant finding was a worse refractive outcome in the collagen vascular diseases group compared with controls. There were no other statistical differences detected in the other systemic disease groups. CONCLUSIONS: In our experience, LASIK can be performed effectively and safely in selected patients with stable and controlled systemic diseases with favorable postoperative anatomic and visual outcomes. The absolute exclusion of certain systemic contraindications should be reconsidered.

Long-term evaluation of eyes with central corneal thickness <400 µm following laser in situ keratomileusis.

PURPOSE: To study long-term refractive and visual outcomes of laser in situ keratomileusis (LASIK) in eyes with a postoperative thin central cornea. METHODS: In this retrospective observational case series, we studied 282 myopic eyes with a normal preoperative topographic pattern and postoperative thin corneas (<400 µm) that had at least 3 years of follow-up after LASIK in three private clinics. The main outcome measures were safety, efficacy, predictability, percent tissue altered, and complications. RESULTS: The mean postoperative central corneal thickness was 392.05 µm (range: 363.00-399.00 µm). After a mean follow-up of 6.89±2.35 years (standard deviation), the safety index was 1.17, the efficacy index was 0.94, and predictability (±1.00 diopter [D]) was 73.49. The mean residual stromal bed thickness was 317.34±13.75 µm (range: 275-356 µm), the mean flap thickness was 74.76±13.57 µm (range: 55-124 µm), and the mean percent tissue altered was 37.12%±3.62% (range: 27.25%-49.26%). No major complications were recorded. CONCLUSION: LASIK with a resultant central cornea thickness <400 µm seems to be effective, safe, and predictable provided that preoperative topography is normal and the residual stromal bed thickness is >275 µm.

Thin flap laser in situ keratomileusis: analysis of contrast sensitivity, visual, and refractive outcomes.

PURPOSE: To analyze refractive, visual, and contrast sensitivity outcomes of laser in situ keratomileusis (LASIK) performed under thin flaps (less than 100 microm), and compare them with those of conventional thicker flaps. SETTING: Clínica Baviera, Instituto Oftalmológico Europeo, Madrid, Spain. METHODS: This retrospective study comprised 280 consecutive eyes that had LASIK for myopia using the Moria LSK-One microkeratome and the Technolas 217C excimer laser. Efficacy, predictability, and contrast sensitivity indicators were compared between 3 groups of flap thickness: thin (<100 microm, n = 105), medium (100 to 129 microm, n = 122), and thick (>130 microm, n = 53). RESULTS: Refractive results were excellent and comparable between the 3 groups; however, visual outcomes-measured as efficacy, postoperative evolution of uncorrected visual acuity, and contrast sensitivity-test were significantly better in the thin flap group. Efficacy results were 92.9%, 91.0%, and 81.0% in the thin, medium, and thick flap groups, respectively (P < .05), and the rate of enhancements was 0%, 2.3%, and 5.6%, respectively. With regard to contrast sensitivity, changes between preoperative and postoperative values at month 3 of follow-up, the thin flap group achieved the preoperative levels at 3 spatial frequencies (3, 6, and 18 cycles per degree), while the thicker flap groups maintained lower than preoperative levels at more than 2 spatial frequencies. When comparing contrast sensitivity values between the 3 groups, the thin flap group also obtained the best results at lower spatial frequencies. CONCLUSIONS: Thin flap LASIK is a safe technique to correct myopic defects since it blends the advantages of surface and lamellar procedures (minimal debilitation of corneal biomechanical architecture with the rapid and comfortable visual recovery of lamellar approaches). Moreover, it achieves excellent refractive outcomes, a lower rate of enhancements, and a good visual performance with better contrast sensitivity test results.

Incidence of corneal infections after laser in situ keratomileusis and surface ablation when moxifloxacin and tobramycin are used as postoperative treatment.

PURPOSE: To assess the incidence, culture results, and visual outcomes of infectious keratitis after laser in situ keratomileusis (LASIK) and surface ablation when topical moxifloxacin was added to postoperative prophylaxis with tobramycin. SETTING: Clínica Baviera, Instituto Oftalmológico Europeo, Bilbao, Spain. DESIGN: Retrospective case series review. METHODS: The medical records of 55 255 patients (108 014 eyes) who had LASIK and surface ablation were reviewed to identify cases of infectious keratitis. The incidence, risk factors, clinical course, days to diagnosis, treatment, and final visual outcomes were recorded. These data were compared with previously published data of 221 437 eyes that received postoperative tobramycin alone. RESULTS: Post-LASIK infectious keratitis was diagnosed in 10 eyes (9 patients) and post-surface ablation infectious keratitis in 11 eyes (10 patients). The onset of infection was early in 40.00% of cases after LASIK and in 36.36% after surface ablation. Cultures were positive in 2 cases after surface ablation. Immediate flap lifting and irrigation with antibiotics were performed in all eyes after LASIK. The final corrected distance visual acuity was 20/20 or better in 7 cases after LASIK (70.00%) and 7 cases after surface ablation (63.64%) and 20/40 or better in all cases after LASIK or surface ablation. CONCLUSIONS: The incidence of infectious keratitis decreased from 0.025% to 0.011% (P < .001) per procedure after LASIK and from 0.200% to 0.066% (P < .001) after surface ablation. Infectious keratitis was less frequent after LASIK than after surface ablation. The frequency of infection, mainly early-onset infection, was lower when the postoperative treatment was tobramycin and moxifloxacin rather than tobramycin alone. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

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.

Factors that influence outcomes of hyperopic laser in situ keratomileusis.

PURPOSE: To analyze the influence of preoperative corneal curvature, postoperative keratometric power, and the amount of correction on the outcomes of hyperopic laser in situ keratomileusis (LASIK). SETTING: Clínica Baviera, Instituto Oftalmológico Europeo, Madrid, Spain. METHODS: In this retrospective study, the records of 376 eyes that had LASIK for hyperopia using the Moria LSK-One microkeratome and the Technolas-Keracor 217C excimer laser were reviewed. The results were analyzed by preoperative hyperopia (5 subgroups) and by preoperative (more than and less than 43.0 diopters [D]) and postoperative (more than and less than 48.0 D) mean keratometry. RESULTS: A statistically significant keratometry regression was found in the +3.00 to +3.90 D range (P <.01), a significant decrease in predictability in the +4.00 to +4.90 D range (P <.05), and a significant worsening in safety in the highest range (+6.00 to +7.90 D; P <.05). Comparative analysis of the > or = +4.00 D and <+4.00 D groups showed statistically significant differences in most measurement parameters. The preoperative keratometry did not influence postoperative results with the exception of poorer predictability in the group of preoperative flat corneas in which a high degree of hyperopia was corrected; ie, spherical equivalents within +/-0.50 D were found in 40.4% and 61.0% of cases with flat and steep corneas, respectively (P <.05). The efficacy and safety in eyes that achieved a postoperative keratometry >48.00 D did not differ significantly from the efficacy and safety in eyes that had a lower final keratometric power. CONCLUSIONS: The factor that negatively influenced the outcome of hyperopic LASIK was the degree of hyperopia corrected. Preoperative keratometry did not significantly influence the postoperative results, and postoperative keratometry >48 D did not result in significant worsening of visual results when the attempted correction was less than +4.00 D.

Long-term comparison of laser in situ keratomileusis versus laser surface ablation in corneas thinner than 470 µm.

PURPOSE: To compare long-term refractive and visual outcomes of laser in situ keratomileusis (LASIK) and laser surface ablation in eyes with corneas thinner than 470 µm. SETTING: Private clinics, Spain. DESIGN: Comparative case series. METHODS: The study comprised eyes with myopic error and corneas thinner than 470 µm that had at least 2.9 years of postoperative follow-up between September 2001 and June 2007. The main outcome measures were safety, efficacy, predictability, and complications. RESULTS: The mean central corneal thickness was 462.0 µm (range 440 to 469 µm) in the LASIK group (n = 40) and 458.1 µm (range 420 to 469 µm) in the laser surface ablation group (n = 88). All eyes had normal preoperative topography. In the LASIK group after a mean follow-up of 5.1 years ± 1.5 (SD), the safety index was 1.07, efficacy was 0.99, and predictability (± 1.00 diopter [D]) was 0.93. In the laser surface ablation group after a mean follow-up of 4.8 ± 1.3 years, the safety index was 1.01, efficacy was 0.93, and predictability (± 1.00 D) was 0.92. The mean residual corneal bed thickness in all eyes was 345 ± 25 µm (range 270 to 399 µm). No major complications occurred. The safety index was better in the LASIK group than in the laser surface ablation group. CONCLUSION: Both techniques were effective, safe, and predictable in eyes with corneas thinner than 470 µm, normal preoperative topography, and a residual corneal bed thickness greater than 250 µm.

Association between ocular dominance and spherical/astigmatic anisometropia, age, and sex: analysis of 1274 hyperopic individuals.

PURPOSE: To determine the association between ocular dominance and spherical/astigmatic anisometropia, age, and sex in hyperopic subjects. METHODS: The medical records of 1274 hyperopic refractive surgery candidates were filtered. Ocular dominance was assessed with the hole-in-the-card test. Refractive error (manifest and cycloplegic) was measured in each subject and correlated to ocular dominance. Only subjects with corrected distance visual acuity of >20/22 in each eye were enrolled, to exclude amblyopia. Associations between ocular dominance and refractive state were analyzed by means of t-test, χ(2) test, Spearman correlation, and multivariate logistic regression analysis. RESULTS: Right and left eye ocular dominance was noted in 57.4 and 40.5% of the individuals. Nondominant eyes were more hyperopic (2.6 ± 1.27 diopters [D] vs. 2.35 ± 1.16 D; P < 0.001) and more astigmatic (-1.3 ± 1.3 D vs. -1.2 ± 1.2 D; P = 0.003) compared to dominant eyes. For spherical equivalent (SE) anisometropia of >2.5 D (n = 21), the nondominant eye was more hyperopic in 95.2% (SE 4.7 ± 1.4 D) compared to 4.8% (1.8 ± 0.94 D; P < 0.001) for the dominant eye being more hyperopic. For astigmatic anisometropia of >2.5 D (n = 27), the nondominant eye was more astigmatic in 89% (mean astigmatism -3.8 ± 1.1 D) compared to 11.1% (-1.4 ± 1.4 D; P < 0.001) for the dominant eye being more astigmatic. CONCLUSIONS: The present study is the first to show that the nondominant eye has a greater degree of hyperopia and astigmatism than the dominant eye in hyperopic subjects. The prevalence of the nondominant eye being more hyperopic and more astigmatic increases with increasing anisometropia.

Indications for intrastromal corneal ring segments in ectasia after laser in situ keratomileusis.

PURPOSE: To evaluate clinical results of intrastromal corneal ring segments (ICRS) in a large series of post-laser in situ keratomileusis (LASIK) ectasia and determine which clinical parameters were related to the success of this technique. SETTINGS: Vissum Corporation and Clínica Baviera Group, Alicante, Spain. DESIGN: Case series. METHODS: Intrastromal corneal ring segments were implanted to correct the spherocylindrical error and improve visual acuity. Based on a previously described grading system, the best indications for ICRS implantation to treat post-LASIK ectasia were evaluated. The variables related to favorable outcomes over a 12-month follow-up were determined. RESULTS: Patients who lost 2 or more lines due to post-LASIK ectasia had a mean gain of +2.89 lines of corrected distance visual acuity (CDVA) after ICRS implantation (P<.001) and a mean CDVA of 0.81 (95% confidence interval, 0.74-0.88). In contrast, patients who did not lose vision after ectasia had a mean loss of -2.00 lines of CDVA after the ICRS implantation (P<.001). The odds ratio of a gain of at least 1 line of CDVA was 18 times greater for those who had lost 2 or more lines of CDVA after ectasia. CONCLUSIONS: The best indications for ICRS were a loss of 2 or more lines of CDVA after ectasia and post-LASIK ectasia grade 4. Patients who do not have vision loss after ectasia and those classified as grade 1 should not be considered candidates for ICRS implantation. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.