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Purpose: To determine the effect of laser in situ keratomileusis (LASIK) on retinal nerve fiber layer (RNFL) thickness measurements obtained by scanning laser polarimetry with variable corneal compensation (SLP-VCC)., Setting: Gimbel Eye Centre, Calgary, Alberta., Methods: Retinal nerve fiber layer thickness measurements were performed in both eyes of 25 consecutive healthy patients the day of LASIK surgery and 1 month after by trained examiners using the GDx-VCC nerve fiber analyzer. Thickness measurements and all other parameters provided by the software of the machine before and after LASIK were analyzed using the paired Student t test., Results: Mean age of the patients was 39 years +/- 9.6 (SD) (range 24 to 57 years). The mean preoperative spherical equivalent was -4.15 +/- 1.76 diopters (D) (range -1.0 to -7.50 D) and the mean postoperative spherical equivalent, 0.12 +/- 0.39 D (range -0.75 to +1.00 D). Mean ablation depth was 62 +/- 23 mum. No statistically significant difference was found in SLP parameters after LASIK (P<.05). No clinically significant difference in RNFL thickness measurements was noted in any eye., Conclusion: These data suggest that SLP-VCC mean thickness measurements are not influenced by LASIK-induced alterations in corneal architecture. Measurements obtained with SLP-VCC before surgery may be used for future comparisons.

Objective: A retrospective study was undertaken to evaluate long-term anatomic and visual outcomes in eyes of children who underwent bilateral intraocular lens implantation., Design: The study design was a review of medical records of 24 children operated on for bilateral cataracts and posterior chamber-intraocular lenses., Participants: Twenty-four children operated on for bilateral cataracts by 1 surgeon between February 1980 and February 1995 were studied., Intervention: Cataract extraction with bilateral posterior chamber-intraocular lens implantation was performed., Main Outcome Measures: Best-corrected visual acuity, visual acuity without correction, intraocular pressure, manifest refraction, and any intraoperative or postoperative complications were measured., Results: At last follow-up (mean follow-up, 50.8 months; range, 10-149 months), the intraocular lens was in good position and the intraocular pressure was normal without medication in all eyes. Four years after surgery, 79.2% (19 of 24) of first eyes achieved a best-corrected visual acuity of 20/40 or better compared to 66.7% (16 of 24) of second eyes. No eye had any loss in best-corrected visual acuity. In first eyes of 3- to 8-year olds at the time of surgery, 73.3% (11 of 15) achieved a spherical equivalent within 2 diopters of the intended at 4 years after surgery compared to 80% of second eyes. In the 9- to 18-year-old group, 88.9% (8 of 9) of first eyes and 100% of second eyes achieved a spherical equivalent within 2 diopters of the intended at 4 years after surgery. Intraoperative and postoperative complications were minimal., Conclusions: Long-term anatomic and visual results have been gratifying in this series of patients with bilateral implants.

Purpose: To identify pitfalls and offer hints on achieving a successful outcome during the early laser in situ keratomileusis (LASIK) learning process., Setting: Gimbel Eye Centre, Calgary, Alberta, Canada., Methods: This was a retrospective review of the preoperative planning, surgical procedure, intraoperative and postoperative problems, and early postoperative anatomic and refractive results in the first 73 eyes that had LASIK., Results: Intraoperative complications included failure of the keratome to make a cut, excessively thin cap, repositioning difficulty, and inadequate intraocular pressure elevation. Early postoperative complications included excessive central and peripheral wrinkling of the cap, peripheral lipid deposits, and central edema of the cap. One month postoperatively, mean spherical equivalent refraction was -0.90 diopters (D) (range +1.75 to -6.00 D), and 45 eyes had a best corrected visual acuity between 20/15 and 20/40., Conclusion: Our retrospective review of the problems experienced during the early LASIK learning process should help novice lamellar refractive surgeons avoid such problems and shorten the learning curve.

A prospective study was undertaken to investigate the effect of pharmacological pupillary dilation and constriction on corneal topography. Corneal topography was performed using the EyeSys system on 28 normal subjects before and after pupil dilation, constriction, and then with the pupil intact (no medication). Our results show that both flattening and steepening of the corneal curvature were found in all three examination periods. The numbers of corneas with flattening and steepening in each examination period were compared and found not to be statistically different. Mean change of corneal flattening was compared with mean change of corneal steepening in each examination period and again no significant difference was found. These results indicate that the slight changes in corneal power and radius following pharmacological pupillary dilation or constriction may be due to either the inability to repeat by the subjects, or error by observers or instrument.

We investigated trabeculotomy ab externo as a means of optimizing intraocular pressure (IOP) control in glaucoma patients having phacoemulsification and implantation of an intraocular lens (IOL). A prospective, randomized, controlled study was performed to evaluate the effect on IOP and the incidence of complications associated with combined phacoemulsification and trabeculotomy ab externo. The study group had the combined procedure, while the control group had only phacoemulsification with IOL implantation. A total of 106 patients were randomized, and the IOP for each group was compared at 3, 6, 12, and 24 months. At two years, the mean IOP reduction was 6.1 mm Hg in the study group and 3.8 mm Hg in the control group (P = .001). There were no complications in the control group. Two complications (2/53 or 3.8%) occurred in the study group: a small tear in Descemet's membrane and a postoperative microhyphema. There was no increase in medication in either the study or control group. Combined phacoemulsification and trabeculotomy ab externo represents an option to lower IOP and potentially reduce the need for pressure-lowering medications in patients with primary open-angle glaucoma and visually significant cataracts.

Background: Photorefractive keratectomy relies on precise ablation of cornea stromal tissue to achieve a desired change in refraction. The routine technique for photorefractive keratectomy has been manual debridement of the epithelium prior to performing excimer laser ablation. We investigated whether laser ablation versus manual debridement of the corneal epithelium influences the refractive result., Methods: A retrospective matched controlled study analyzing the refractive outcome of 46 eyes after excimer laser photorefractive keratectomy was performed. Half of the eyes had the corneal epithelium ablated with the excimer laser, while the other half had mechanical removal. Topical postoperative corticosteroid dosing was different in the two groups. All photorefractive keratectomies were performed by the same surgeon (H.V.G.). The two groups were analyzed for statistical differences in refractive outcomes and corneal haze after 6 months., Results: The mean preoperative spherical equivalent refraction in the laser removal group was -5.11 diopters (D), and -5.09 D in the manual group. At 6 months postoperatively, the mean spherical equivalent refraction in the laser group was +0.03 D and -0.40 D for the manual group (p = .21). At no point postoperatively was there any significant difference in the mean refractive outcome or variance of the refractive results between the two groups, although there was a trend toward greater correction with laser ablation of epithelium. There was no statistical difference in the amount of stromal haze by slit-lamp microscopy in the two different debridement groups. There was no significant difference in final uncorrected visual acuity, rate of reepithelialization, or reported incidence of halos or glare between the two groups., Conclusion: There was a tendency toward greater refractive correction at 6 months using the laser for corneal epithelial removal than manual debridement, although the difference was not statistically significant. The trend toward slightly higher correction emphasizes the need for care when removing epithelium with the laser to prevent concomitant stromal ablation.

Reports of the visual, refractive, and patient satisfaction results after photorefractive keratectomy (PRK) are now becoming available. The visual, refractive, and patient satisfaction results of 52 patients after bilateral excimer laser photorefractive keratectomy for myopia were studied. Patient satisfaction was measured using a five-part questionnaire. Initial patients obtained an overcorrection which necessitated adjusting the programmed correction to 75% of targeted correction.

With the development of posterior chamber lenses and continuous curvilinear capsulorhexis, and with the availability of viscoelastic agents, the use of intraocular lenses (IOLs) in children is becoming more popular. Since 1982, we have implanted posterior chamber IOLs (PC-IOLs) in the capsular bags of 61 cataractous eyes of 46 children and adolescents. The goal was in-the-bag placement facilitated by the use of a small capsulectomy, and, since 1984, by the use of the continuous curvilinear capsulorhexis. Forty-four cataracts were congenital, 13 were traumatic, and 4 were developmental. Cataract extraction with IOL implantation was performed in 16 (26%) preschool cases (ages 2 through 5), in 31 (51%) child cases (ages 6 through 12), and 14 (23%) adolescent cases (ages 13 through 18). Surgical and postoperative complications were minimal. Visual results were good. Fifty-six percent of preschoolers, 87% of children, and 86% of adolescents achieved 20/40 or better best corrected vision, with 79% of the total cohort achieving 20/40 or better. Overall, 35% achieved an uncorrected visual acuity of 20/40 or better. All but two cases had improvement in best corrected vision; if 20/20 was not attained, the cause was mainly due to deprivation amblyopia. Forty-eight percent of patients were within a diopter of emmetropia.