Refractive errors among children, adolescents and adults attending eye clinics in Mexico.

AIM: To assess the proportion of refractive errors in the Mexican population that visited primary care optometry clinics in fourteen states of Mexico. METHODS: Refractive data from 676 856 patients aged 6 to 90y were collected from optometry clinics in fourteen states of Mexico between 2014 and 2015. The refractive errors were classified by the spherical equivalent (SE), as follows: sphere+½ cylinder. Myopia (SE>-0.50 D), hyperopia (SE>+0.50 D), emmetropia (-0.50≤SE≤+0.50), and astigmatism alone (cylinder≥-0.25 D). A negative cylinder was selected as a notation. RESULTS: The proportion (95% confidence interval) among all of the subjects was hyperopia 21.0% (20.9-21.0), emmetropia 40.7% (40.5-40.8), myopia 24.8% (24.7-24.9) and astigmatism alone 13.5% (13.4-13.5). Myopia was the most common refractive error and frequency seemed to increase among the young population (10 to 29 years old), however, hyperopia increased among the aging population (40 to 79 years old), and astigmatism alone showed a decreasing trend with age (6 to 90y; from 19.7% to 10.8%). There was a relationship between age and all refractive errors (approximately 60%, aged 50 and older). The proportion of any clinically important refractive error was higher in males (61.2%) than in females (58.3%; P<0.0001). From fourteen states that collected information, the proportion of refractive error showed variability in different geographical areas of Mexico. CONCLUSION: Myopia is the most common refractive error in the population studied. This study provides the first data on refractive error in Mexico. Further programs and studies must be developed to address the refractive errors needs of the Mexican population.

Refractive Lenticule Extraction Complications.

PURPOSE: To report the complications associated with refractive lenticule extraction (ReLEx) in its 2 modalities: femtosecond lenticule extraction (FLEx) and small incision lenticule extraction (SMILE). METHODS: In this retrospective review of a consecutive clinical case series, all patients who had a complicated ReLex FLEx or ReLEx SMILE procedure at the Cornea and External Disease Department at the Instituto de Oftalmologia Fundacion Conde de Valenciana, Mexico City, Mexico, were included. Demographic characteristics, type of complication, and final refraction and visual outcomes were recorded. RESULTS: Our study comprised 94 eyes in the FLEx group and 160 eyes in the SMILE group with a mean follow-up period of 36 months. In the FLEx group, 15 eyes (18.3%) presented surgery-related complications, including suction loss, black spots, bubbles in the interface, and lenticule misdissection. In the SMILE group, 43 eyes (26.9%) had complications, including an epithelial defect (the most frequent), suction loss, opaque bubble layer, cap rupture, and lenticule rupture. CONCLUSIONS: Although ReLEx complications can occur, most of them are related to inexperience and have a favorable resolution with no lasting effect on the patient's final visual acuity.

Long-term refractive outcomes of posterior chamber phakic (spheric and toric implantable collamer lens) intraocular lens implantation.

To report the long-term refractive outcomes, safety, predictability, efficacy and complications of 349 eyes treated with posterior chamber phakic intraocular lenses (pIOLs). A retrospective review of consecutive clinical cases of patients who underwent spheric implantable collamer lens (ICL) and toric ICL (TICL) implantation. The study included 349 eyes of 216 patients with sphere between +8 to -24 diopters (D) and 0 to -6.5 D of astigmatism. Statistical analysis was performed to identify differences between preoperative and postoperative refractive outcomes. Main outcome measures were preoperative and postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical and cylindrical errors and spherical equivalent and significant postoperative complications. 194 eyes were treated with TICL and 155 eyes with ICL. The mean age of the patients was 29 ± 6.7 years. The mean preoperative sphere was -10.35 ± 5.1 D (+8 to -24) and the postoperative sphere was -0.09 ± 1.06 D (+3.25 to -6.5), p < 0.001. Preoperative cylinder was -2.63 ± 1.44 (0 to -6.5 D) and postoperative cylinder was -0.97 ± 0.89 D (0 to -3.5), p < 0.001. The preoperative mean spherical equivalent was -11.6 ± 5.12 D (+7.875 to -25.625) and postoperative spherical equivalent was -0.52 ± 1.03 (+2.25 to -6.75), p < 0.001. The mean preoperative UDVA was 1.72 ± 0.49 and postoperative UDVA was 0.23 ± 0.22, p < 0.001. The mean preoperative CDVA was 0.21 ± 0.17 and postoperative CDVA was 0.12 ± 0.138, p < 0.001. The implantation of posterior chamber pIOLs is a safe, predictable and effective strategy to manage refractive errors during long-term follow-up.

Ocular dermoids: 116 consecutive cases.

PURPOSE: The aim was to describe the demographic and clinical data of 116 consecutive cases of ocular dermoids. METHODS: This was a retrospective case series and a review of clinical records of all the patients diagnosed with ocular dermoids. Both demographic and clinical data were recorded. Statistical analysis was performed with SPSS v. 18. Descriptive statistics are reported. RESULTS: The study included 116 consecutive patients with diagnosis consistent with ocular dermoids: corneal 18% (21), dermolipomas 38% (44), and orbital 44% (51). Sixty-five percent (71) were female, and 46% (54) were detected at birth. Secondary manifestations: amblyopia was present in 14% (3), and strabismus was detected in 6.8% (8). The Goldenhar syndrome was the most frequent syndromic entity in 7.5% (12) of the patients. Surgical resection was required on 49% (25) of orbital dermoids, 24% (5) of corneal dermoids, and 13% (6) of dermolipomas. CONCLUSIONS: Orbital dermoids were the most frequent variety, followed by conjunctival and corneal. In contrast to other reports, corneal dermoids were significantly more prevalent in women. Goldenhar syndrome was the most frequent syndromatic entity.

Implantable collamer lenses after intracorneal ring segments for keratoconus.

To report the clinical characteristics and visual outcomes of patients with keratoconus treated with posterior chamber phakic intraocular lenses after implantation of intracorneal ring segments (ICRS). This retrospective study included 11 eyes of eight patients diagnosed with keratoconus treated with ICRS and posterior chamber phakic intraocular lenses. The preoperative and postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), preoperative and postoperative keratometric data, manifest refraction and spherical equivalent were recorded. No complications were observed. At 38.18 ± 18.7 months of follow-up, the mean spherical error was -0.06 ± 0.46 D (+0.75 to -0.75 D) and cylindrical error of -1.22 ± 0.65 D (-0.25 to -1.5 D). The preoperative spherical equivalent was -10.52 ± 5.88 D (-3.12 to -22.75 D) and the postoperative spherical equivalent was -0.68 ± 0.45 D (0 to -1.25 D), p < 0.001. The preoperative and postoperative UDVA were 1.31 ± 0.37 logMAR (mean 20/400 Snellen, 0.69-1.77 logMAR) and 0.14 ± 0.04 (mean 20/30 Snellen, 0.09-0.47 logMAR), with a p value <0.001. The preoperative and postoperative CDVA were 0.289 ± 0.14 logMAR (mean 20/40 Snellen, 0-0.477 logMAR) and 0.16 ± 0.08 (mean 20/25 Snellen, 0.09-0.39 logMAR), with a p value of 0.007. Combined treatment of keratoconus with ICRS and posterior chamber phakic intraocular lenses was a safe and effective procedure for high refractive errors induced by keratoconus in these selected patients.

Refractive lens exchange with toric intraocular lenses in keratoconus.

PURPOSE: To report the clinical characteristics and surgical outcomes of patients with nonprogressive keratoconus treated with in-the-bag toric intraocular lens (IOL) implantation. METHODS: A retrospective review was conducted of the medical records of patients diagnosed with keratoconus treated with refractive lens exchange (RLE) and in-the-bag toric IOL implantation (models T3 to T9, AcrySof SN60TT; Alcon Laboratories Inc). Age, pre- and postoperative uncorrected (UDVA) and corrected distance visual acuity (CDVA), objective and subjective refraction, spherical equivalent refraction, total keratometric power, total astigmatism, axis, and toric IOL model and power were analyzed. All cases had topographic and/or refractive stability for at least 1 year prior to undergoing IOL implantation. RESULTS: Nineteen eyes of 13 patients (mean age 48.15 ± 6.6 years), including 12 patients with a topographic diagnosis of keratoconus and 1 with pellucid marginal degeneration, were evaluated. Mean follow-up after RLE was 7.89 ± 6.61 months. Mean preoperative sphere was -5.25 ± 6.40 diopters (D), and mean postoperative sphere was 0.22 ± 1.01 D (P<.001). Mean preoperative cylinder was 3.95 ± 1.30 D, which decreased to 1.36 ± 1.17 D postoperatively (P<.001). Mean pre- and postoperative spherical equivalent refractions were -7.10 ± 6.41 D and -0.46 ± 1.12 D, respectively (P<.001). Preoperative mean UDVA was 1.35 ± 0.36 D (20/447 Snellen) and postoperative mean UDVA was 0.29 ± 0.23 D (20/39 Snellen) (P<.001). CONCLUSIONS: Toric IOL implantation may be an effective therapeutic option in the optical rehabilitation of patients with stable and nonprogressive keratoconus.

Spontaneous Rotation of a Toric Implantable Collamer Lens.

We present a case of toric implantable collamer lens (TICL) spontaneous rotation in a patient with myopic astigmatism. A 23-year-old female underwent TICL implantation. Preoperative uncorrected visual acuity (UCVA) was 20/800 and 20/1200, respectively, with -7.75 -4.25 × 0° and -8.25 -5.25 × 180°. The left eye achieved an UCVA of 20/30. After 3 months of successful implantation of TICL in the left eye, the patient presented with a sudden decrease in visual acuity in the left eye. UCVA was 20/100 with a refraction of +2.50 -4.50 × 165°. We observed the toric marks with a 30° rotation from the original position and decided to reposition the TICL, obtaining a final UCVA of 20/25, which remained stable at 6 months' follow-up. TICL can present a considerable rotation that compromises visual acuity. The relocation of TICL is a safe and effective procedure to recover visual acuity due to significant spontaneous TICL rotation.