Carlos Lisa

Collagen copolymer toric posterior chamber phakic intraocular lens in eyes with keratoconus.

PURPOSE: To assess the safety, efficacy, stability, and predictability of collagen copolymer toric phakic intraocular lens (pIOL) implantation to correct myopia and astigmatism in eyes with keratoconus. SETTING: Fernández‐Vega Ophthalmological Institute, Oviedo, Spain. METHODS: This prospective study comprised keratoconic eyes that had implantation of a toric Intraocular Collamer Lens. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, and postoperative complications were evaluated 1, 3, 6, and 12 months postoperatively. RESULTS: Preoperatively, the mean spherical equivalent in the 30 eyes (21 patients) was −5.38 diopters (D) ± 3.26 (SD) (range −13.50 to −0.63 D) and the mean cylinder, −3.48 ± 1.24 D (range −1.75 to −6.00 D). At 12 months, 86.7% of the eyes were within ±0.50 D of the attempted refraction and all eyes were within ±1.00 D. For the astigmatic components J0 and J45, 83.3% of eyes and 86.7% of eyes, respectively, were within ±0.50 D. The mean Snellen UDVA was 0.81 ± 0.20 and the mean CDVA, 0.83 ± 0.18; CDVA was 20/40 or better in 29 eyes 96.7% of eyes and 20/25 or better in 22 eyes (73.3%). No eyes lost more than 2 lines of CDVA; 29 eyes (96.7%) maintained or gained 1 or more lines. The efficacy index was 1.07 and the safety index, 1.16. There were no complications or adverse events. CONCLUSIONS: The results confirm that toric ICL implantation is a predictable, effective procedure to correct ametropia in eyes with keratoconus. Predictability and stability were achieved early and remained fairly stable up to 12 months. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.

Objective vs subjective vault measurement after myopic implantable collamer lens implantation.

PURPOSE To evaluate the relationship between subjective measurements of vault and objective values measured with Visante optical coherence tomography (OCT) in eyes receiving an implantable contact lens (ICL) for myopia correction. DESIGN Observational cross-sectional study. METHODS SETTING Fernández-Vega Ophthalmological Institute, Oviedo, Spain. PATIENTS Four hundred and fifty-two eyes from 246 patients were elected to be implanted with a Visian ICL V4 (STAAR Surgical Inc, Monrovia, California, USA). OBSERVATION PROCEDURES Subjective and objective measurements of vault after implantation of ICL. MAIN OUTCOME MEASURES Subjective vault classified in 5 levels assessed using an optical section during slit-lamp examination. Objective vault was measured with Visante OCT (Carl Zeiss Meditec Inc, Dublin, California, USA). RESULTS Average values of objective and subjective vault were 414 +/- 228 microm and 2.1 +/- 1.0, respectively and both parameters were highly correlated (r = 0.82; P < .001). Differences in average objective vault were statistically significant among the 5 groups of subjective vault (P < .001). Subjective vault 0 corresponded to a mean OCT value of 62 +/- 49 microm with 99% confidence interval (CI) [38; 86] microm; eyes with vault 1 to 203 +/- 93 microm with 99% CI [176; 230] microm; eyes with vault 2 to 402 +/- 131 microm with 99% CI [378; 425] microm; eyes with vault 3 to 594 +/- 146 microm, 99% CI [554; 633] microm; and vault 4 to 794 +/- 182 microm with 99% CI [713; 875] microm. CONCLUSIONS Subjective and objective values of vault are highly correlated. In 99% of cases within the CI, objective values for eyes subjectively classified within a certain level vary within a narrow interval (+/-25 to 80 microm) around the mean value, and this interval is characteristic of each subjective level.

Central vault after phakic intraocular lens implantation: Correlation with anterior chamber depth, white-to-white distance, spherical equivalent, and patient age

PURPOSE: To compare the central postoperative vault of a phakic intraocular lens (pIOL) to correct myopia, myopic astigmatism, and hyperopia and identify ocular and lens parameters that might predict the vault amount. SETTING: Fernández‐Vega Ophthalmological Institute, Oviedo, Spain. DESIGN: Cohort study. METHODS: Three months after implantation of Implantable Collamer Lens pIOLs to correct myopia, hyperopia, and myopic astigmatism, central vault was measured using optical coherence tomography. Patients were divided into groups according to the preoperative anterior chamber depth (ACD) to compare the effects of ACD, white‐to‐white (WTW) distance, and lens diameter on postoperative pIOL vault. RESULTS: Hyperopic pIOLs had statistically significantly lower vault followed by myopic pIOLs and toric pIOLs, which had a higher mean value and narrower range (260 to 860 μm). Measured vaults had a positive correlation with preoperative ACD (r = .32, P<.001) and WTW (r = .29, P<.001) and a negative correlation with preoperative spherical equivalent (SE) (r = −0.21, P<.001) and patient age (r = −0.12, P=.025). Eyes with a vault of 250 μm or less had a shallower ACD than eyes with a vault between 250 μm and 750 μm (mean difference −0.11 mm; P=.012) and those with a vault greater than 750 μm (mean difference −0.25 mm; P<.001). CONCLUSIONS: Central vaulting was lower in hyperopic eyes. Current nomograms for pIOL diameter selection based on ACD and WTW might yield ideal vault and may have to be adjusted for older patients, shallower ACD, lower WTW, and lower SE. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.

Intrastromal corneal ring segments and posterior chamber phakic intraocular lens implantation for keratoconus correction

PURPOSE: To evaluate the efficacy, safety, and predictability of sequential implantation of Keraring intrastromal corneal ring segments (ICRS) and an Implantable Collamer Lens phakic intraocular lens (pIOL) with corneal relaxing incisions for refractive correction of keratoconus. SETTING: Fernández‐Vega Ophthalmological Institute, Oviedo, Spain. DESIGN: Cohort study. METHODS: This study comprised patients with keratoconus who had ICRS implantation followed 6 months later by pIOL implantation with corneal relaxing incisions. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities and residual refractive errors, analyzed using vector analysis, were recorded preoperatively, 6 months after ICRS implantation, and 6 months after pIOL implantation. RESULTS: The study enrolled 40 eyes (31 patients). The mean UDVA (decimal) was 0.11 Snellen ± 0.05 (SD) preoperatively, 0.18 ± 0.14 Snellen 6 months after ICRS implantation (P=.001), and 0.50 ± 0.27 Snellen 6 months after pIOL implantation (P<.0001). The mean CDVA was 0.56 ± 0.23 Snellen, 0.68 ± 0.25 Snellen, and 0.73 ± 0.20 Snellen, respectively (all P<.0001). Six months after pIOL implantation, the efficacy index was 0.88 and the safety index, 1.28. At 6 months, 65% of eyes were within ±1.00 diopter (D) of the desired refraction and 45% were within ±0.50 D. The mean spherical equivalent after pIOL implantation was −1.19 ± 1.33 D. CONCLUSION: Sequential ICRS and pIOL implantation plus corneal relaxing incisions provided good visual and refractive outcomes, indicating that it is a predictable procedure for refractive correction of keratoconus. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.

Intrastromal Corneal Ring Segment Implantation in 409 Paracentral Keratoconic Eyes.

Purpose: To assess the efficacy outcomes of implanting intrastromal corneal ring segments (ICRS) to correct paracentral keratoconus. Methods: Four hundred nine eyes with paracentral keratoconus, in which the differences between the axes of refractive cylinder and the corneal flattest meridian and the comatic aberration map were less than 30 degrees, were evaluated before and after the implantation of Ferrara-type ICRS. Snellen uncorrected and best-corrected distance visual acuity, residual refractive errors analyzed with vector analysis, and the root mean square for corneal coma-like aberration for a pupil size of 4.5 mm were recorded before and 6 months after ICRS implantation. Results: The mean uncorrected distance visual acuity (Snellen decimal scale) rose from 0.19 ± 0.19 before ICRS implantation to 0.42 ± 0.30 after implantation (P < 0.0001). The mean preoperative best-corrected distance visual acuity was 0.69 ± 0.24 and the postoperative value was 0.77 ± 0.23 (P < 0.0001). The safety index was 1.13. The spherical equivalent declined steeply after ICRS implantation (P < 0.0001). Cylinder power decreased by more than 50% in 71% of the eyes. The root mean square for corneal coma-like aberration for a 4.5-mm pupil changed from 1.32 ± 1.01 &mgr;m before surgery to 1.06 ± 0.85 &mgr;m after surgery (P ⩽ 0.001). Conclusions: The Ferrara-type ICRS implantation is a safe and effective procedure for treating patients with keratoconus that meets the morphological characteristics of the sample under study.

Femtosecond laser-assisted intrastromal corneal ring segment implantation for high astigmatism correction after penetrating keratoplasty.

Purpose To assess the visual and refractive outcomes of femtosecond laser–assisted implantation of Ferrara‐type intrastromal corneal ring segments (ICRS) in post‐penetrating keratoplasty (PKP) eyes. Setting Instituto Oftalmológico Fernández‐Vega, Oviedo, Spain. Design Cohort study. Methods Patients with previous PKP had ICRS implantation after femtosecond laser tunnel creation. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities and residual refractive errors were recorded before and 6 months after ICRS implantation. The power vector method was used to analyze refractive errors preoperatively and postoperatively. Results This study enrolled 32 eyes of 30 patients. The mean UDVA (Snellen decimal) changed from 0.16 ± 0.15 (SD) preoperatively to 0.43 ± 0.28 postoperatively (P<.0001). Postoperatively, the UDVA was 20/40 or better in 40.6% of eyes. The mean CDVA was 0.67 ± 0.22 preoperatively and 0.80 ± 0.19 postoperatively (P<.0001). Postoperatively, the CDVA was better than 20/40 in 96.9% of eyes and 20/25 or better in 56.2% of eyes. By 6 months postoperatively, no eye had lost more than 2 lines of CDVA, 4 eyes lost 1 line, 6 eyes had no change, 9 eyes gained 1 line, and 13 eyes gained 2 or more lines. The safety index at 6 months was 1.20. The spherical equivalent and astigmatism components were significantly reduced after ICRS implantation (P<.04). Conclusion Intrastromal corneal ring segment implantation using the femtosecond laser may be a good alternative for high astigmatism correction in post‐PKP eyes. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Long-Term Follow-Up of Intrastromal Corneal Ring Segments in Paracentral Keratoconus with Coincident Corneal Keratometric, Comatic, and Refractive Axes: Stability of the Procedure

Purpose To assess the long-term outcomes of implanting intrastromal corneal ring segments (ICRS) in paracentral keratoconic eyes. Methods 58 eyes with paracentral keratoconus with coincident refractive, keratometric, and comatic axes were evaluated. Uncorrected (UDVA) and corrected (CDVA) distance visual acuity and refractive errors were recorded before and at all follow-up visits. The postoperative follow-up was 5 years. Patients were divided into two groups: group I (30 years old or younger) and group II (more than 30 years old). Results The mean UDVA (logMAR) rose from a preoperative 0.83 ± 0.31 to a five-year postoperative 0.42 ± 0.33 (P < 0.0001). The mean CDVA varied from 0.16 ± 0.17 to 0.11 ± 0.18 (P = 0.0003). Both the UDVA and CDVA were stable over the postoperative period in both groups (P > 0.05). The spherical equivalent and the refractive cylinder declined steeply after ICRS implantation in both groups (P < 0.001), and were stable over the postoperative period (P > 0.05). The keratometric values were also stable over the postoperative follow-up. Conclusion Ferrara-type ICRS implantation in keratoconus that meets the characteristics of the sample under study reduces the refractive error at the same time as it improves postoperative UDVA and CDVA six months after surgery and that these results remain stable over five years of follow-up.

Intraocular Pressure After Implantation of a Phakic Collamer Intraocular Lens With a Central Hole.

PURPOSE To investigate the middle-term intraocular pressure (IOP) results after implantation of a posterior chamber collagen copolymer phakic intraocular lens (IOL) (V4c Visian; STAAR Surgical Co., Nidau, Switzerland) with a central hole in patients with myopia. METHODS This retrospective study enrolled patients who had implantation of a phakic IOL with a central hole. IOP, central vault, and adverse events were evaluated 1, 3, 6, 12, and 24 months postoperatively. RESULTS The study enrolled 763 eyes (384 patients, 128 men and 256 women). Mean follow-up was 7.0 ± 7.2 months (range: 1 to 24 months). The mean IOP was 13.2 ± 2.1 mm Hg preoperatively. Postoperatively, the mean IOP was 12.4 ± 1.7 mm Hg at 1 month, 12.5 ± 1.8 mm Hg at 3 months, 12.6 ± 1.3 mm Hg at 6 months, 12.6 ± 1.4 mm Hg at 12 months, and 12.7 ± 1.1 mm Hg at 24 months. Only one case (0.13%) presented an increased IOP (> 21 mm Hg) during the observation period. No pupillary block or acute angle closure was recorded. IOP at the final follow-up visit was 12.8 ± 1.3 mm Hg. CONCLUSIONS Implantation of central hole phakic IOL in myopic patients provided good and safe IOP outcomes throughout the 24-month observation period. [J Refract Surg. 2017;33(4):244-249.].

Implantable Collamer Lens® for Management of Pseudophakic Ametropia in Eyes With a Spectrum of Previous Corneal Surgery

PURPOSE To assess the visual outcomes, predictability, and safety of the Implantable Collamer Lens (ICL) (STAAR Surgical, Inc., Monrovia, CA) for the management of residual pseudophakic refractive error. METHODS Forty-nine pseudophakic eyes of 40 patients in which myopic, hyperopic, or toric ICLs were implanted were retrospectively analyzed. Twenty-nine eyes had been implanted with a monofocal intraocular lens (IOL) and 20 eyes had a multifocal IOL. All IOLs were implanted in the capsular bag. Of the 49 eyes included, 6 had residual refractive error after phacoemulsification without corneal pathology or surgical alteration (virgin cornea group), 12 had LASIK or photorefractive keratectomy (PRK) (excimer laser group), 8 had radial keratotomy, 5 had intrastromal corneal ring segments (ICRS) implantation, 11 had penetrating keratoplasty, and 7 had deep anterior lamellar keratoplasty (DALK). Uncorrected and corrected (CDVA) distance visual acuity and manifest refraction were evaluated. RESULTS The efficacy/safety indices were 0.92/1.10, 0.98/1.13, 1.04/1.11, 0.90/1.13, 0.79/1.17, and 0.71/1.23 for the virgin cornea, excimer laser, radial keratotomy, ICRS, penetrating keratoplasty, and DALK groups, respectively. No eye lost one or more lines of CDVA. The virgin cornea, excimer laser, and radial keratotomy groups showed better predictability and accuracy, with 96.2% spherical equivalent within ±1.00 diopters (D). The ICRS, penetrating keratoplasty, and DALK groups demonstrated approximately 50% spherical equivalent within ±1.00 D. There were no intraoperative or postoperative complications. CONCLUSIONS Good refractive outcomes and a strong safety record support the use of the ICL for the correction of residual refractive error in pseudophakic eyes with previous corneal surgery. [J Refract Surg. 2018;34(10):654-663.].

Clinical Outcomes of Sequential Intrastromal Corneal Ring Segments and an Extended Range of Vision Intraocular Lens Implantation in Patients with Keratoconus and Cataract

Purpose To evaluate efficacy, safety, and predictability of sequential Ferrara-type intrastromal corneal ring segments (ICRS) and an extended range of vision intraocular lens (IOL) implantation in patients with keratoconus and cataract. Methods This study comprised patients with keratoconus and cataract that had ICRS implantation followed 6 months later by extended range of vision IOL implantation. The uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and residual refractive errors, analysed using vector analysis, were recorded preoperatively, 6 months after ICRS implantation, and 6 months after IOL implantation, respectively. Results The study enrolled 17 eyes (11 patients). The mean UDVA (logMAR scale) was 1.15 ± 0.67 preoperatively, 0.88 ± 0.69 six months after ICRS implantation (P = 0.005), and 0.27 ± 0.18 six months after IOL implantation (P < 0.0001). The CDVA changed from 0.26 ± 0.15 (logMAR) before surgery to 0.17 ± 0.08 six months after Ferrara-type ICRS implantation (P = 0.002) and to 0.07 ± 0.06 six months after IOL implantation (P < 0.0001). The spherical equivalent and the refractive cylinder declined steeply after IOL implantation (P < 0.001). The magnitude of depth of focus was 2.60 ± 1.02 D. There were no statistically significant differences in visual acuity for a defocus range from +0.50 D to −0.50 D (P > 0.1). Conclusion Sequential Ferrara-type ICRS and an extended range of vision IOL implantation provided good visual and refractive outcomes, being an effective, safe, and predictable procedure for the treatment of selected cases of patients with keratoconus and cataract. In addition, this approach provides an increase of tolerance to defocus.