Ten-year follow-up of posterior chamber phakic intraocular lens with central port design in patients with low and normal vault

PURPOSE

To assess the clinical outcomes and postoperative complications of the implantable collamer lens (ICL) with a central port throughout 10 years of follow-up in patients with low and normal vault.

SETTING

Fernández-Vega Ophthalmological Institute, Oviedo, Spain.

DESIGN

Retrospective and comparative case series.

METHODS

This study included eyes that underwent a V4c ICL implantation with 10 years of follow-up. The eyes were divided into 2 groups according to the vault at 1 year postoperatively: vault <250 μm and between 250 μm and 800 μm. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), intraocular pressure (IOP), endothelial cell density (ECD), vault, complications, and secondary surgeries were analyzed.

RESULTS

37 and 90 eyes were enrolled in the low and normal-vault groups, respectively. No differences in UDVA, CDVA, and refraction were found between the groups over 10 years of follow-up. No cases developed ICL-induced anterior subcapsular opacity over the follow-up period. 2 (5.4%) and 8 (8.9%) eyes in the low and normal-vault groups, respectively, required ICL exchange. 1 (2.8%) and 2 (2.2%) eyes in the low and normal-vault groups, respectively, required excimer laser to correct residual refractive error. The IOP remained stable throughout the 10-year follow-up. The loss in ECD from that preoperatively to 10 years postoperatively was 3.8% and 4.5% in the low and normal-vault groups, respectively ( P = .4). No pigment dispersion glaucoma or other vision-threatening complications were reported.

CONCLUSIONS

This study shows good long-term outcomes of the V4c ICL, supporting that the central hole provides safety to the procedure and prevents the potential risk associated with low vault.

Triple Procedure: A Stepwise Combination of Deep Anterior Lamellar Keratoplasty and Cataract Surgery

PURPOSE

The aim of this study was to evaluate clinical outcomes of the combined surgery (triple procedure) of deep anterior lamellar keratoplasty (DALK), phacoemulsification, and intraocular lens (IOL) implantation using a new surgical strategy.

METHODS

The study included 43 eyes of 43 patients who underwent a triple procedure. Twenty-six eyes with good visibility through the cornea underwent phacoemulsification before the stromal dissection. Seventeen eyes with bad visibility underwent the DALK procedure first until achieving enough visibility to perform the lensectomy. IOL power calculation was performed for a postoperative estimated flat keratometry of 43.5 and aiming to avoid hyperopic postoperative refraction. The postoperative visual examination included uncorrected and corrected distance visual acuity (CDVA) measurements and manifest refraction.

RESULTS

The mean follow-up time after suture removal was 3.06 ± 2.14 years. Mean CDVA significantly changed from 0.86 ± 0.56 logMAR preoperatively to 0.37 ± 0.28 logMAR in the last visit ( P < 0.0001). The percentage of eyes with CDVA ≤0.3 logMAR changed from 6.9% preoperatively to 62.8%. No eyes lost lines of vision after surgery, and 80% experienced an improvement of 2 or more lines. The safety index was 2.2. The mean postoperative refractive sphere was +0.13 ± 2.04 D, and the postoperative refractive cylinder was -4.02 ± 2.24 D. Only 2 cases (4.65%) obtained postoperative hyperopic astigmatism. No intraoperative complications were found.

CONCLUSIONS

Combined surgery of DALK, phacoemulsification, and IOL implantation is an effective and safe procedure. Depending on the corneal transparency, different surgical strategies can be established to provide more efficacy and safety.

Effect of intrastromal corneal ring segments on in vivo corneal biomechanics in keratoconus: 1-year results

PURPOSE

To evaluate the 1-year effects of the implantation of intrastromal corneal ring segments (ICRS) in keratoconus (KC) on the dynamic corneal response (DCR) parameters obtained with the Corvis.

SETTING

Fernández-Vega Ophthalmological Institute, Oviedo, Spain.

DESIGN

Prospective, single-center, clinical study.

METHODS

Included were patients who underwent ICRS implantation for KC over a period of 1 year. On the day of the surgery and at least 6 months after ICRS implantation, the following measurements were made: corrected distance and uncorrected distance visual acuity, corneal tomography indices with the Pentacam, biomechanically corrected intraocular pressure and the Corvis DCRs (integrated inverse concave radius, deformation amplitude ratio, stiffness parameter at first applanation, stress-strain index [SSI] and the highest concavity radius).

RESULTS

30 eyes were included with a mean follow-up time of 15 months. Statistical analysis showed that ICRS implantation induced significant improvements in corneal biomechanics measurements between preoperative and long-term follow-up as demonstrated by a significant increase in SSI (P = .003). To confirm that this difference was actually induced due to a stiffening between early postoperative (previously published) and long-term an additional t-test was done between month 1 and late follow-up which confirmed a significant stiffening in the value of SSI (P = .01).

CONCLUSIONS

Patients implanted with ICRS alone for KC showed a significantly stiffer response due to increased structural support compared with preoperative values and 1 month postoperative.

Clinical and Aberrometric Outcomes of a New Implantable Collamer Lens for Myopia and Presbyopia Correction in Phakic Patients

PURPOSE

To assess the clinical and aberrometric outcomes of a new Implantable Collamer Lens (EVO Viva ICL; STAAR Surgical) to correct moderate to high myopia and presbyopia.

METHODS

The study included 80 eyes of 40 patients who had bilateral EVO Viva ICL implantation. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, presbyopic add power, binocular through-focus visual acuity, total ocular spherical aberration (SA), coma aberration, and root mean square of ocular higher order aberrations (RMS HOAs) (i-Trace Aberrometer; Tracey Technologies) for a 4.5-mm pupil size were evaluated.

RESULTS

The mean binocular postoperative UDVA and CDVA were 0.09 ± 0.19 and 0.02 ± 0.03 logMAR, respectively. The postoperative spherical equivalent was -0.61 ± 0.54 diopters (D). The presbyopic add power reduced from +1.31 ± 0.74 D preoperatively to +0.44 ± 0.58 D after surgery (P < .0001). The mean visual acuity was 0.1 logMAR or better (20/25 or better) across the vergence range from +0.50 to -1.50 D, better than 0.2 logMAR (20/32 or better) up to the vergence of -2.00 D, and remained better than 0.3 logMAR (20/40 or better) up to the vergence of -2.50 D. The total ocular aberrations induced by EVO Viva ICL were -0.34 ± 0.09 µm of SA, 0.24 ± 0.18 µm of coma, and 0.26 ± 0.12 µm of RMS HOAs.

CONCLUSIONS

The outcomes support that the new ICL might be a good alternative for myopia and presbyopia correction in patients aged between 45 and 55 years. Further studies are needed to evaluate the threshold lens misalignment from which the patient´s visual quality would be affected. [J Refract Surg. 2023;39(9):589-596.].

Intrastromal Corneal Ring Segments Implantation After Deep Anterior Lamellar Keratoplasty for Astigmatism Correction: Mid-term and Long-term Follow-up

PURPOSE

The aim of this study was to assess the long-term outcomes of implanting intrastromal corneal ring segments (ICRSs) using a femtosecond laser for correcting astigmatism in patients who had previous deep anterior lamellar keratoplasty (DALK) throughout a 5-year follow-up period.

METHODS

This retrospective study included 40 eyes of 40 patients with previous DALK and astigmatism ≥3.00 D who underwent Ferrara-type ICRS implantation. The manifest refraction, uncorrected (UDVA) and corrected (CDVA) distance visual acuity (logMAR), and corneal topography were recorded preoperatively and at 6, 12, 36, and 60 months postoperatively.

RESULTS

The mean UDVA (logMAR scale) improved from 1.39 ± 0.55 preoperatively to 0.71 ± 0.37 at 6 months postoperatively ( P < 0.0001). The mean CDVA (logMAR) significantly improved from 0.36 ± 0.17 to 0.22 ± 0.12 at 6 months after surgery ( P < 0.0001). Both UDVA and CDVA remained unchanged throughout the follow-up ( P = 0.09). Postoperatively, no eyes lost lines of CDVA compared to preoperatively, and around 80% of the eyes gained lines of CDVA. The safety index remained stable at a value of 1.4 throughout the follow-up. The refractive cylinder decreased from -6.86 ± 2.62 D preoperatively to -2.33 ± 1.09D at 6 months postoperatively ( P < 0.0001), and subsequently, it was stable over the postoperative period ( P = 0.2). The maximum and minimum keratometry measurements significantly decreased after surgery and remained stable over the postoperative follow-up period ( P > 0.07).

CONCLUSIONS

This study shows the long-term viability of Ferrara-type ICRS implantation using a femtosecond laser as a surgical alternative for astigmatism correction in post-DALK eyes.

Spontaneous corneal clearance after graft detachment in DMEK

Descemet Membrane detachment is a potential complication after Descemet Membrane Endothelial Keratoplasty (DMEK). Here, we present a unique case of a DMEK surgery in a complicated eye that suffered a nearly complete DMEK graft detachment and later a graft opacification with a pseudo-anterior chamber. In Mid-November 2020, a planned DMEK was performed in a 64-year-old male patient due to corneal decompensation. Four months after DMEK, a fibrotic DMEK graft was seen across the anterior chamber with a pseudo-anterior chamber; however, the recipient cornea showed complete clearance with an endothelial cell count of about 1204 cells/mm2 and a best-corrected visual acuity of 20/25. Three months later, we observed a significant opacification of the detached graft, and the best-corrected distance visual acuity decreased to 20/63. We proceeded with the graft removal without performing a second DMEK. Ten months after graft removal, the cornea remained clear with an endothelial cell count of about 510 cells/mm², and the best-corrected visual acuity was 20/25.

Beam-Shaping Extended Depth of Focus Intraocular Lens: Optical Assessment With Corneas of Increasing Spherical Aberration

PURPOSE

To assess the optical quality and halo formation of a beam-shaping extended depth-of-focus (EDOF) intraocular lens (IOL) (AcrySof IQ Vivity; Alcon Laboratories, Inc) with corneas of long-range spherical aberration (SA) such as those resulting from myopic laser ablations.

METHODS

The optical quality of the EDOF IOL and a reference monofocal IOL was evaluated with three corneas (A, B, and C, with SA =+0.135, +0.290, +0.540 µm, respectively, for a 5.15-mm pupil at the IOL plane). The through-focus modulation transfer function area (MTFa) curves were obtained between -5.00 and +2.00 diopters (D) defocus range. The halo was also assessed with the three corneas.

RESULTS

Through-focus MTFa curves for a 4.5-mm IOL pupil showed a slight decrease in the maximum MTFa value provided by the EDOF IOL compared to the monofocal IOL in the three corneal situations (A: 45.9 vs 38.6 units; B: 41.1 vs 33.1 units, and C: 26.9 vs 23.8 units). For the 3.0-mm pupil, the EDOF IOL also had lower maximum MTFa than the monofocal IOL; however, the depth-of-focus increased to -2.20 D. With corneas A and B, the halo induced was of low energy with both IOLs. With cornea C, the EDOF IOL created a much larger and intense halo.

CONCLUSIONS

The EDOF IOL provided a good distance optical performance and an extended range of focus of approximately 2.00 D, with a halo of low intensity when evaluated with a corneal SA similar to the one induced by a low to moderate myopic ablation. With a high myopic ablation, the halo induced would be of considerable size and energy. [J Refact Surg. 2023;39(2):95-102.].

Long-Term Follow-Up of a 150° Arc-Length Intrastromal Corneal Ring Segment Implantation in Post-LASIK Ectasia

PURPOSE

To evaluate the outcomes of implanting a 150° arc-length intrastromal corneal ring segment (ICRS) using a femtosecond laser in patients with post-LASIK ectasia throughout a 5-year follow-up period.

METHODS

This study enrolled 45 eyes of 45 patients diagnosed with post-LASIK ectasia who underwent a 150° arc-length Ferrara-type ICRS implantation. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, residual refractive errors, and root mean square (RMS) for coma-like aberration were evaluated preoperatively and at 6-, 12-, 36, and 60 months postoperatively.

RESULTS

Mean UDVA (logMAR) ameliorated from 0.53 ± 0.33 preoperatively to 0.26 ± 0.24 at 6 months postoperatively (p < 0.0001). Mean CDVA improved from 0.12 ± 0.13 to 0.04 ± 0.06 (p < 0.0001). Mean UDVA and CDVA remained stable throughout the 5-year follow-up (p > 0.1). No eyes lost lines of CDVA at any follow-up visit compared to preoperatively, and most eyes gained lines. The eyes with a refractive cylinder ≤ 2.00 D varied from 26.7% preoperatively to more than 75% at all postoperative follow-up visits. The maximum keratometry was significantly flattened (p < 0.0001), and the RMS for corneal coma-like aberration was halved (p < 0.0001). 93.3% of the eyes did not show signs of disease progression or regression of the visual or refractive outcomes at any follow-up visits.

CONCLUSION

These results suggest that implanting a single 150° arc-length Ferrara-type ICRS is a safe, effective and stable procedure for visual restoration in post-LASIK ectasia. In very few cases, visual and/or refractive instability was experienced throughout the follow-up.

Three-year follow-up of posterior chamber phakic intraocular lens with a central port design after deep anterior lamellar keratoplasty

Background

To evaluate clinical outcomes of the Visian implantable collamer lens (ICL) with a central port to correct myopia and astigmatism after deep anterior lamellar keratoplasty (DALK) for keratoconus throughout 3 years of follow-up.

Methods

This study included 20 eyes of 20 patients that underwent V4c ICL (13 eyes with a spherical ICL and 7 eyes with a toric ICL) implantation after DALK. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, intraocular pressure (IOP), endothelial cell density (ECD), and vault were analyzed.

Results

The mean UDVA improved from the preoperative 1.18 ± 0.33 logMAR to 0.25 ± 0.14 logMAR at 6 months after surgery (P < 0.0001) and remained unchanged throughout the whole follow-up (P = 0.4). All eyes gained lines of CDVA compared to preoperative values. At the last follow-up visit, all eyes achieved CDVA of 0.2 logMAR or better and 13 eyes (65%) 0.1 logMAR or better. At 6 months post-surgery, all eyes (100%) had a spherical equivalent within ± 1.50 D, and 19 (95%) within ± 1.00 D. The mean manifest spherical equivalent was stable over the postoperative follow-up (P = 0.25). No significant increase in IOP occurred in any case throughout the 3 years of follow-up. The loss in ECD from the preoperative baseline at the last follow-up visit was 2.27%.

Conclusions

The clinical outcomes suggest that the V4c ICL implantation for correction of myopia and regular astigmatism in post-DALK eyes was satisfactory in terms of effectiveness, safety, and stability during 3 years of follow-up.

Optical and Clinical Outcomes of an Enhanced Monofocal Intraocular Lens for High Hyperopia

PURPOSE

To evaluate the optical and clinical performance of an enhanced monofocal intraocular lens (IOL) (TECNIS Eyhance ICB00; Johnson & Johnson Vision) in patients with high hyperopia and a short axial length.

METHODS

Power mapping, wavefront analysis, and the through-focus modulation transfer function area (TF-MTFa) were measured in vitro for three IOL powers (10.00, 20.00, and 30.00 diopters [D]). The clinical study included 22 patients with an axial length of less than 22.5 mm. Uncorrected (UDVA) and corrected (CDVA) distance visual acuity and binocular defocus curve were evaluated 6 months postoperatively.

RESULTS

For the three IOL powers, the power mapping revealed an increase in positive power from the periphery to the center of the lens, providing an extra positive correction of 1.00 D for a 2-mm pupil size. The TF-MTFa curves showed only a peak of maximum MTFa at the distance focus. As the pupil size became smaller, there was a focus extension effect, providing an extended depth of focus of up to -1.50 D for a 2-mm pupil size. No significant dependency of the IOL base power on the power profile, wavefront, or optical quality was found. The clinical outcomes showed that all patients achieved a binocular CDVA of 0.1 logMAR or better. The mean visual acuity was better than 0.1 logMAR between +0.50 and -1.50 D of defocus. At a vergence of -2.00 D, the visual acuity was 0.11 ± 0.13 logMAR.

CONCLUSIONS

The monofocal enhanced IOL provided good distance optical and visual quality and optimal visual acuity up to an intermediate-near vision distance of 50 to 40 cm in patients with high hyperopia and a short axial length. [J Refract Surg. 2022;38(9):572-579.].

Femto-LASIK after Deep Anterior Lamellar Keratoplasty to Correct Residual Astigmatism: A Long-Term Case Series Study

Purpose: To evaluate the long-term outcomes of femtosecond laser-assisted in situ keratomileusis (Femto-LASIK) to correct residual astigmatism after deep anterior lamellar keratoplasty (DALK). Methods: This retrospective case series study included 10 eyes that underwent Femto-LASIK after a DALK. The refractive error, uncorrected (UDVA) and corrected (CDVA) distance visual acuities, thinnest corneal thickness (TCT), and central corneal thickness (CCT) were registered. The postoperative follow-up ranged between 36 and 60 months. Results: All surgeries were uneventful, with no intra- or postoperative complications. The mean UDVA (Snellen scale) rose from 0.13 ± 0.05 to 0.47 ± 0.15 six months after Femto-LASIK (p < 0.001). All cases experienced a significant improvement in UDVA. None of the eyes lost lines of CDVA, and seven eyes (70%) improved the CDVA compared to preoperative values. The refractive cylinder changed from a preoperative value of −3.88 ± 1.00 D to −0.93 ± 0.39 six months after Femto-LASIK (p < 0.0001). In eight eyes (80%), the UDVA and refractive outcomes remained stable at postoperative follow-up visits. In contrast, one eye experienced a refractive regression over the follow-up. TCT and CCT were stable at the different postoperative follow-up visits. Conclusions: Our findings suggest that Femto-LASIK might safely and effectively corrects residual astigmatism after DALK. Despite these encouraging results, further long-term studies, including a larger number of cases, are required to confirm the safety of the procedure. The refractive stability in eyes with prior RK might be lower than for other DALK indications.

The Effect of Intracorneal Ring Segments Implantation for Keratoconus on In Vivo Corneal Biomechanics Assessed With the Corvis ST

PURPOSE

To evaluate the effect of the implantation of intracorneal ring segments (ICRS) in keratoconus on the dynamic corneal response (DCR) parameters obtained with the Corvis ST (Oculus Optikgeräte GmbH).

METHODS

This prospective clinical study included patients who underwent ICRS implantation for keratoconus over a period of 1 year. On the day of the surgery and at least 1 month after ICRS implantation, the following measurements were made: corrected and uncorrected distance visual acuity, corneal tomography indices with the Pentacam (Oculus Optikgeräte GmbH), biomechanically corrected intraocular pressure (bIOP), Corvis ST DCR parameters, integrated inverse concave radius (1/R), deformation amplitude ratio (DA ratio), stiffness parameter at first applanation (SP-A1), stress-strain index (SSI), and highest concavity radius (HRC).

RESULTS

Fifty-one eyes of 40 patients were included with a median follow-up time of 3 months (interquartile ratio [IQR]: 2 to 6 months). Statistical analysis showed that ICRS implantation did not affect corneal biomechanical measurements evaluated with the Corvis ST, which was demonstrated by non-significant changes in the SP-A1 (P = .637), 1/R (P = .647), HRC (P = .177), DA ratio (P = .735), and SSI (P = .501). Additionally, the results showed that bIOP measurements were not significantly affected by ICRS implantation (P = .113).

CONCLUSIONS

ICRS implantation does not affect corneal biomechanical measurements in early follow-up. [J Refract Surg. 2022;38(4):264-269.].

Optical and Clinical Outcomes of an Extended Range of Vision Intraocular Lens

PURPOSE

To assess the in vitro optical quality and halo formation of the AcrySof IQ Vivity intraocular lens (IOL) (Alcon Laboratories, Inc) and to evaluate the clinical outcomes in patients who had bilateral implantation of this IOL.

METHODS

The optical quality was evaluated with the PMTF optical bench (Lambda-X). Through-focus modulation transfer function area (MTFa) curves between -5.00 and +2.00 diopters (D) were obtained for 3- and 4.5-mm pupil apertures. The halo was assessed in vitro with a test bench. The clinical study included 30 patients. Uncorrected (UDVA) and corrected (CDVA) distance visual acuity and binocular defocus curve were evaluated 6 months postoperatively.

RESULTS

The through-focus MTFa curve for the 4.5-mm pupil size showed only one peak at distance focus (38.4 units). For the 3-mm pupil size, the through-focus MTFa showed a lower peak of MTFa (28.9 units), located at -0.70 D, and an extended depth of focus up to -2.20 D. The halo formed was larger and more intense compared to a standard monofocal IOL. The clinical outcomes at 6 months revealed satisfactory visual acuity outcomes. All patients achieved a binocular CDVA of 0.1 logMAR or better. The mean visual acuity was better than 0.2 logMAR between +1.00 and -2.00 D of defocus. At a vergence of -2.50 D, the visual acuity was 0.31 ± 0.09 logMAR.

CONCLUSIONS

The AcrySof IQ Vivity IOL provided good distance optical and visual quality and an extended range of focus of approximately 2.00 D, obtaining an optimal or functional visual acuity up to 50 to 40 cm. The halo formed was low intensity overall, but higher intensity than a monofocal IOL. [J Refract Surg. 2022;38(3):168-176.].

Protector role of intraocular lenses under artificial light conditions

INTRODUCTION

The aim of this work is to analyse, in an in vitro model, the possible protective effects of ultraviolet- (UV-) or UV/ blue-filtering intraocular lens (IOLs) under LED lighting conditions.

METHODS

10 models of IOLs were evaluated. Light transmission spectrum was recorded from 300 to 800 nm, in steps of 1 nm. Photodamage in vitro model was induced in ARPE-19 cells by blue LED light (465-475 nm). Changes in cell viability and oxidative stress variables were studied to assess the protective effect of IOLs.

RESULTS

UV/blue-filtering IOLs models block blue light spectrum in different proportion and UV-filtering IOLs blocking wavelength below 400 nm. However, in vitro study under blue LED light exposure does not show protective effects related with mitochondrial dysfunction and oxidative stress of UV/blue-filtering IOLs.

CONCLUSIONS

The current in vitro study suggest that UV/blue filtering IOLs are not useful in terms of photoprotection in artificial light conditions. The results obtained indicate that it is needed to give attention to other IOLs parameters besides the type of filter, as it seems they could have influence also protective role.

A New Pre-descemetic Corneal Ring (Neoring) in Deep Anterior Lamellar Keratoplasty for Moderate-Advanced Keratoconus: A Pilot 2-Year Long-Term Follow-Up Study

Purpose: To assess the outcomes of implanting a new polymethylmethacrylate (PMMA) ring (Neoring; AJL Ophthalmic) in pre-descemet deep anterior lamellar keratoplasty (PD-DALK) procedure for moderate-advanced keratoconus.

Methods: This prospective study included 10 eyes of 10 patients with moderate-advanced keratoconus who underwent PD-DALK with Neoring implantation. Neoring was implanted in a pre-descemetic pocket. The post-operative examination included refraction, corrected distance visual acuity (CDVA), corneal tomography, and endothelial cell density (ECD). The root mean squares (RMSs) for coma-like aberrations and spherical aberration were evaluated for a pupil size of 4.5 mm. The junctional graft (Tg) and host (Th) thicknesses were measured. The post-operative follow-up was 24 months.

Results: Post-operative CDVA was 0.82 ± 0.14 (decimal scale), 100% of the eyes achieved a CDVA of 0.7 (decimal scale). The refractive cylinder was −2.86 ± 1.65 2-years after surgery. No eyes had a post-operative refractive cylinder ≥5.00 D and in five eyes (50%), it was ≤2.50 D. At the last visit, the mean keratometry was 45.64 ± 1.96 D, the RMS for coma-like aberrations was 0.30 ± 0.15 μm and spherical aberration was 0.22 ± 0.09. The mean ECD remains without changes over the follow-up (P = 0.07). At the last visit, Tg and Th were 679.9 ± 39.0 and 634.8 ± 41.2 μm, respectively. The thickness of the complex (host-Neoring) was 740.6 ± 35.6 μm. In all cases, this thickness was thicker than Tg.

Conclusion: The results of this study suggest that PD-DALK along Neoring implantation is a viable, effective, and safe option to optimize the post-operative results for moderate-severe keratoconus.

Small fiber neuropathy in the cornea of Covid-19 patients associated with the generation of ocular surface disease

Purpose

To describe the association between Sars-CoV-2 infection and small fiber neuropathy in the cornea identified by in vivo corneal confocal microscopy.

Methods

Twenty-three patients who had overcome COVID-19 were recruited to this observational retrospective study. Forty-six uninfected volunteers were also recruited and studied as a control group. All subjects were examined under in vivo confocal microscopy to obtain images of corneal subbasal nerve fibers in order to study the presence of neuroma-like structures, axonal beadings and dendritic cells. The Ocular Surface Disease Index (OSDI) questionnaire and Schirmer tear test were used as indicators of Dry Eye Disease (DED) and ocular surface pathology.

Results

Twenty-one patients (91.31%) presented alterations of the corneal subbasal plexus and corneal tissue consistent with small fiber neuropathy. Images from healthy subjects did not indicate significant nerve fiber or corneal tissue damage. Eight patients reported increased sensations of ocular dryness after COVID-19 infection and had positive DED indicators. Beaded axons were found in 82.60% of cases, mainly in patients reporting ocular irritation symptoms. Neuroma-like images were found in 65.22% patients, more frequently in those with OSDI scores >13. Dendritic cells were found in 69.56% of patients and were more frequent in younger asymptomatic patients. The presence of morphological alterations in patients up to 10 months after recovering from Sars-CoV-2 infection points to the chronic nature of the neuropathy.

Conclusions

Sars-CoV-2 infection may be inducing small fiber neuropathy in the ocular surface, sharing symptomatology and morphological landmarks with DED and diabetic neuropathy.

Eight-year follow-up of Artiflex and Artiflex Toric phakic intraocular lens

PURPOSE

To analyse long-term efficacy, safety, visual and refractive stability and physiological changes of Artiflex Myopia and Toric phakic intraocular lenses (pIOL) separately throughout an 8-year follow-up.

DESIGN

Retrospective cohort study.

METHODS

A total of 67 eyes of 37 patients underwent Artiflex Myopia (47 eyes) or Artiflex Toric (20 eyes) implantation for correcting myopia and/or astigmatism. Follow-up evaluations were performed 1, 3, 5 and 8 years after surgery. Preoperative and postoperative data included corrected (CDVA) and uncorrected distance visual acuity (UDVA), manifest refraction, endothelial cell density (ECD) and intraocular pressure (IOP) assessments. Efficacy and safety indexes were analysed. The vectorial analysis was performed using the Thibos method.

RESULTS

Mean CDVA and UDVA of both pIOLs significantly improved from preoperative to 1 year after implantation, and then it remained stable over the 8-year follow-up. The efficacy and safety indexes after 8 years were 0.94 ± 0.16 and 1.07 ± 0.18 for Artiflex Myopia and 1.00 ± 0.11 and 1.10 ± 0.15 for Artiflex Toric, respectively. The spherical equivalent (SE) significantly improved after surgery. J0, J45 and SE refractive components showed no changes between postoperative visits. A total ECD loss of 4.8% (p < 0.001) and 10.4% (p = 0.005) was found after 8 years for Artiflex Myopia and Toric, respectively.

CONCLUSIONS

Artiflex Myopia and Toric pIOLs are a safe, efficient and predictable option for the correction of myopia and/or astigmatism. The vectorial analysis showed excellent rotation stability for the toric version.

Seven-year follow-up of posterior chamber phakic intraocular lens with central port design

BACKGROUND

To assess the clinical outcomes of the Visian Implantable Collamer Lens (ICL) with a central port throughout 7 years of follow-up.

METHODS

Eighty-four eyes of 52 patients were evaluated over a follow-up period of 7 years after V4c ICL implantation. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, intraocular pressure (IOP), endothelial cell density (ECD) and vault were analysed.

RESULTS

The mean postoperative UDVA (logMAR) was 0.04 ± 0.11, 0.13 ± 0.19 and 0.17 ± 0.23 at 1-, 5- and 7-years, respectively (P < 0.0001). The mean CDVA (logMAR) remains unchanged throughout a 7-year follow-up period (0.02 ± 0.08 and 0.02 ± 0.08, at 5- and 7-years, respectively, P = 0.2). At all follow-up visits, more than 95% of the eyes achieved a CDVA of 20/25 or better and more than 85% a CDVA of 20/20. At the end of the follow-up (7 years), no eye lost more lines of CDVA, 56 eyes (66.7%) and 28 eyes (33.3%) gained lines of CDVA. At 7-years, the spherical equivalent was - 0.62 ± 0.62 D. No significant increase in IOP (> 20 mmHg or an increase higher than 5 mmHg) occurred in any case throughout the 7-year of follow-up. The loss in ECD from the preoperative baseline at the last follow-up visit was 2.6%. No intraoperative or postoperative complications or adverse events occurred during the follow-up period.

CONCLUSIONS

The outcomes of this study show the long-term viability of the V4c ICL implantation as a surgical option for the correction of myopia.

Visual and Tomographic Outcomes of a 300° Arc-length ICRS Implantation in Moderate to Advanced Central Keratoconus

PURPOSE

To assess the outcomes of implanting a new 300° arc-length intrastromal corneal ring segment (ICRS) in moderate to advanced central hyperprolate keratoconus.

METHODS

Forty-two eyes with moderate to advanced central hyperprolate keratoconus were evaluated before and after implanting an inferior 300° ICRS (AJL Ophthalmic). The clinical measurements taken included manifest refraction, uncorrected (UDVA) and corrected (CDVA) distance visual acuity (logMAR scale), and corneal tomographic analysis (Sirius; Costruzioni Strumenti Oftalmici). Changes in the anterior and posterior corneal surfaces and the root mean square (RMS) for coma-like aberrations for a pupil size of 4.5 mm were evaluated. All examinations were performed before surgery and 6 months after surgery.

RESULTS

The mean UDVA improved from 1.12 ± 0.48 logMAR preoperatively to 0.73 ± 0.37 logMAR postoperatively (P < .0001). The mean CDVA changed from 0.33 ± 0.20 to 0.20 ± 0.11 logMAR (P < .0001). Postoperatively, the CDVA improved by two or more lines in 45.2% of the eyes and increased by one line in 19.04%, and none of the patients lost lines of CDVA. All of the anterior and posterior corneal tomographic parameters analyzed were significantly improved after surgery, except posterior flat keratometry, which remained unchanged. In 80.95% of the eyes, the postoperative mean keratometry was 50.00 diopters or less. The 6-month RMS for coma-like aberrations also declined significantly from 1.57 ± 0.68 to 1.06 ± 0.42 µm after surgery (P < .0001).

CONCLUSIONS

These results suggest that implanting a 300° arc-length ICRS is a safe and effective procedure for treating patients with moderate to advanced central hyperprolate keratoconus and clear cornea. [J Refract Surg. 2021;37(4):249-255.].

Effect of defocus combined with rotation on the optical performance of trifocal toric IOLs

PURPOSE

To objectively analyze the optical quality of the FineVision Toric intraocular lens (IOL) with two cylinder powers when different combinations of rotations and residual refractive errors are induced.

METHODS

This study assessed the FineVision Toric IOL with two different cylinder powers: 1.5 and 3.0 diopters (D). Three different rotation positions were considered: centered, 5° and 10° rotated. An optical bench (PMTF) was used for optical analysis. The optical quality of the IOLs was calculated by the modulation transfer function (MTF) at five different focal points (0.0, 0.25, 0.50, 0.75, and 1.00 D).

RESULTS

The MTF averaged value of the reference situation was 38.58 and 37.74 for 1.5 and 3.0 D of cylinder, respectively. For the 1.5 D cylinder, the combination of 5° of rotation with a defocus of 0.25, 0.50, 0.75, and 1.0 D induced a decrease on the MTF of 12.39, 19.94, 23.43, 24.23 units, respectively. When induced rotation was 10°, the MTF decrease was 17.26, 23.40, 24.33, 24.48 units, respectively. For the 3.0 D cylinder, the combination of 5° with 0.25, 0.50, 0.75, and 1.0 D of defocus, induced a decrease on the MTF of 12.51, 18.97, 22.36, 22.48 units, respectively. When induced rotation was 10°, the MTF decrease was: 18.42, 21.57, 23.08, and 23.61 units, respectively.

CONCLUSION

For both FineVision Toric IOLs there is a certain optical tolerance to rotations up to 5° or residual refractive errors up to 0.25 D. Situations over these limits and their combination would affect the visual quality of patients implanted with these trifocal toric IOLs.

Femtosecond laser-assisted cataract surgery in shallow anterior chamber cases

PURPOSE

To assess the effectiveness, safety and predictability of femtosecond laser-assisted cataract surgery (FLACS) in eyes with shallow anterior chamber (AC).

METHODS

This is a prospective consecutive clinical study. All eyes presented an anterior chamber depth (ACD) ≤ 2.1 mm and were submitted to FLACS with monofocal intraocular lens (mIOL) or trifocal intraocular lens (tIOL) implantation. Uncorrected distance visual acuity (VA) and corrected distance VA values were used to assess efficacy and safety of the surgery. Refraction, intraocular pressure (IOP), endothelial cell density (ECD) and ACD were evaluated before and 6 months post-surgery.

RESULTS

Phacoemulsification was carried out successfully in all eyes, without intra- or postoperative complications. Efficacy and safety indexes were 0.96 and 1.26 for the mIOL group, and 0.87 and 1.01 for the tIOL group, respectively. The mean postoperative spherical equivalent was - 0.06 ± 0.28D and - 0.14 ± 0.38D for the mIOL and tIOL groups, respectively. The ECD varied from 2470 ± 483 to 2009 ± 538 cells/mm² (p < 0.05) and from 2443 ± 319 to 2245 ± 628 cells/mm² (p = 0.06) for the mIOL and tIOL groups, respectively. IOP significantly decreased (p < 0.05) after the surgery from 14.34 to 12.85 mmHg for the mIOL group and from 14.37 to 11.91 mmHg for the tIOL group, with a general reduction of medical hypotensive treatment in both groups (85% of cases required ≤ number of medications). ACD changed significantly (p < 0.05) from 1.96 ± 0.15 mm to 3.75 ± 0.30 mm after the surgery in the mIOL group and from 1.94 ± 0.15 mm to 3.23 ± 0.21 mm for the tIOL group.

CONCLUSION

FLACS with implantation of either mIOL or tIOL may provide good efficacy, safety and predictability in eyes with shallow AC.

Intrastromal corneal ring segment implantation in paracentral keratoconus with perpendicular topographic astigmatism and comatic axis

PURPOSE

To evaluate the outcomes of implanting intrastromal corneal ring segment (ICRS) using two different strategies in a specific paracentral keratoconus phenotype.

METHODS

Eighty-nine eyes with paracentral keratoconus with perpendicular topographic astigmatism and comatic axes were evaluated before and after implanting a 150° arc-length ICRS. Patients were divided into two groups according to the axis where the ICRS was implanted: Group I: comatic axis and Group II: flat topographic axis. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refractive errors, and root mean square (RMS) for coma-like aberration were recorded. The postoperative follow-up was 1 year.

RESULTS

Mean UDVA (logMAR) changed from 0.49 ± 0.37 preoperatively to 0.30 ± 0.32 6 months afterwards (p < 0.001) in the group I and from 0.53 ± 0.34 to 0.37 ± 0.35 (p < 0.001), in the group II. Mean CDVA in group I changed from 0.11 ± 0.18 preoperatively to 0.06 ± 0.14 6 months after surgery (p < 0.001). In group II the improvement did not reach statistical significance (from 0.09 ± 0.10 to 0.07 ± 0.09; p = 0.06). No eyes lost lines of CDVA in group I. Eight eyes (15.7%) lost lines of CDVA in group II. The spherical equivalent decreased after surgery in both groups (p < 0.001). The RMS for corneal coma-like aberration only decreased in the group I (p < 0.001).

CONCLUSION

Both strategies provided safe and effective visual and refractive outcomes in the specific keratoconus phenotype analyzed. The orthopedic strategy provided better visual outcomes than the refractive one.

Implantation of a Trifocal Intraocular Lens in High Myopic Eyes with Nasal-Inferior Staphyloma

Purpose

To assess visual outcomes in high myopic eyes with nasal-inferior staphyloma implanted with a pseudophakic trifocal intraocular lens (IOL).

Methods

We retrospectively analyzed the visual outcomes of 50 eyes of 45 patients who had cataract surgery after AT LISA trifocal IOL implantation. Twenty-five eyes diagnosed with posterior staphyloma (nasal-inferior, type IV and V), and 25 eyes as long eyes. Uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) values were used to assess the efficacy and safety of the surgery. Refraction and defocus curves were also evaluated at 6 months.

Results

No intra- or post-operative problems occurred during the 6 months of follow-up. After the surgery, the mean Snellen decimal UDVA ranged from 0.50 to 1.00, and CDVA from 0.60 to 1.00 for both groups. CDVA was 0.91 and 0.74 for the long eye and nasal-inferior staphyloma groups, respectively. Efficacy and safety indexes were 1.22 and 1.32 for the long eye, and 1.26 and 1.43 for the nasal-inferior staphyloma group, respectively. All eyes of both groups showed a postoperative spherical equivalent within ±1.00D. The long eye group showed the highest percentage of spherical equivalent between −0.13D and +0.13D (56%) and the nasal-inferior staphyloma group was between −0.51D and −0.14D (40%).

Conclusion

The outcomes of the present study show that a trifocal IOL provides good visual acuity in high myopic eyes, being worse for nasal-inferior staphyloma eyes. The degree of tilt of the macular plane is related with the expected visual acuity.

Visual And Refractive Outcomes In Hyperopic Pseudophakic Patients Implanted With A Trifocal Intraocular Lens

Purpose

To assess visual and refractive results after bilateral implantation of a trifocal intraocular lens (IOL) in patients with hyperopia.

Methods

In a retrospective nonrandomized study, 196 eyes of 98 patients had bilateral implantation of a trifocal IOL. The Barrett Universal II formula was used for IOL power calculation. Eyes were divided into two groups for their analysis: low-moderate, with IOL power ranging from 22 to 26 D, and high, with IOL power ranging from 25 to 34 D. Refractive error was used to assess predictability, and corrected distance visual acuity (CDVA) and uncorrected distance visual acuity values were used to assess efficacy and safety of the surgery.

Results

Six months postoperatively, our results revealed a Snellen decimal CDVA of 0.97±0.05 and 0.94±0.09, for the low-moderate and high groups, respectively. The low-moderate hyperopia group showed a 75.23% of eyes with 20/20 of CDVA and 100% of eyes with 20/25 of CDVA, and the high hyperopia group showed 60.95% and 94.29% for these values of visual acuity, respectively. The mean postoperative spherical equivalent was -0.25±0.36D and -0.24±0.42D for low-moderate and high hyperopia groups, respectively. In the case of low-moderate hyperopia group, 81% of eyes were within ±0.50D and 99% within ±1.00D. These values were 78% and 95%, respectively, for the high hyperopic eyes.

Conclusion

Bilateral implantation of a trifocal IOL in hyperopic eyes provided good visual and refractive outcomes. The Barrett Universal II formula was accurate in predicting the IOL power in hyperopic eyes.

Comparison of clinical outcomes between manual and femtosecond laser techniques for intrastromal corneal ring segment implantation

Purpose:

The purpose was to compare the visual, refractive and aberrometric results of intrastromal corneal ring segments implantation with manual dissection and femtosecond laser–assisted surgery.

Methods:

This is a multicentre study, which included consecutive patients with paracentral keratoconus, in which the difference between the axes of the topographic flattest and the coma aberration was <60°, who had Ferrara-type intrastromal corneal ring segment implantation using manual dissection or femtosecond laser technique. LogMAR uncorrected (uncorrected distance visual acuity) and corrected (corrected distance visual acuity) distance visual acuity, refractive errors and the root mean square for corneal coma-like aberration were recorded before and at 6 months after surgery.

Results:

The study included 84 and 110 eyes in the manual group and in the femtosecond group, respectively. After surgery, there was a statistically significant improvement in uncorrected distance visual acuity and corrected distance visual acuity for both groups ( p < 0.0001), and there were no statistically significant differences between groups ( p > 0.3). For both groups, there was a reduction in spherical equivalent after intrastromal corneal ring segment implantation ( p < 0.0001). There were no statistically significant differences between groups in the magnitude of spherical equivalent reduction ( p = 0.34) The magnitude of the root mean square coma-like reduction was 0.93 ± 0.76 and 0.83 ± 0.80 μm in the manual and femtosecond group, respectively ( p = 0.2). While in the femtosecond laser group no complications were reported, in the manual group, the intraoperative or postoperative complications rate was 13.09%.

Conclusion:

Although both surgical techniques provide comparable visual, refractive and aberrometric outcomes, it should be noted that the femtosecond laser is a safer surgical procedure, with no complications reported.

Visual Function after Implantation of a Presbyopia-Correcting Trifocal Intraocular Lens

PURPOSE

To evaluate distance, intermediate, and near visual performance in patients implanted with a trifocal aspheric presbyopia-correcting intraocular lens (IOL).

METHODS

Forty patients were bilaterally implanted with the AcrySofIQ PanOptix IOL after femtosecond laser-assisted lens surgery. Binocular best corrected distance visual acuity (CDVA) (4 m), best distance-corrected near visual acuity (DCNVA) (40 and 30 cm), best corrected distance intermediate visual acuity (DCIVA) (70, 60, and 50 cm), binocular distance contrast sensitivity under photopic conditions (85 cd/m2), and defocus curves were evaluated at 6-months.

RESULTS

Six months postoperatively, the mean binocular Snellen decimal CDVA and DCNVA were 0.94 ± 0.10 (ranging from 0.70 to 1.25) and 0.85 ± 0.13 (ranging from 0.63 to 1.00), respectively. At a distance, all patients showed a cumulative binocular distance-corrected visual acuity of 0.8 or better, and about 80% (n = 31) of the patients had a value of 1.0 (20/20). At near and intermediate distances, all patients showed a cumulative distance-corrected visual acuity of 0.5 (20/40) or better at 30, 40, 50, 60, and 70 cm. Specifically, 50 cm showed the highest percentage of patients with larger values of visual acuity (60% [n = 26] with 20/20). Defocus curve showed a wide range of useful vision with two peaks of best visual acuity at distance and at 50 cm, and the binocular distance contrast sensitivity was within normal limits.

CONCLUSIONS

The outcomes of the present study show that the visual performance obtained with bilateral implantation of the trifocal aspheric AcrySofIQ PanOptix IOL is good at far, intermediate, and near distances.

Comparison of Complication Rates between Manual and Femtosecond Laser-Assisted Techniques for Intrastromal Corneal Ring Segments Implantation in Keratoconus

Purpose: To compare the incidence of complications between manual and femtosecond-laser assisted surgery for intrastromal corneal ring segments (ICRS) implantation.Material and methods: This study included keratoconus patients who had ICRS implantation using manual dissection and using the femtosecond laser with a minimum follow-up of 12 months. Uncorrected (UDVA) corrected (CDVA) distance visual acuity (CDVA), refraction, corneal topography and aberrometry, pachymetry map and slit-lamp microscopy were assessed before and after surgery.Results: The study included 265 eyes in the manual group and 111 in the femtosecond laser group. In the manual group, there were complications in 48 eyes (18.11%); while in the femtosecond laser 4 eyes had a complication (3.6%). In the manual group, the most frequent complications were ICRS exchange/adjustment for visual and refractive enhancement (25 eyes; 9.43%) and late ICRS spontaneous extrusion (15 eyes; 5.66%). In the manual group, 81.25% of complications were observed during the first 3 years of surgeon's experience. Eyes who suffered a complication had preoperatively higher mean refractive (p = .002) and topographic cylinder (p = .003) and lower UDVA (p = .005) and CDVA (p = .002). After a second surgical procedure for complication management visual, refractive and topographic outcomes significantly improved.Conclusion: Manual mechanical ICRS surgery shows a higher rate of intra- and postoperative mechanical and refractive complications when compared to femtosecond laser assisted technique. The incidence is specially higher during the surgeon's first years of implementation of the technique.

Five-Year Follow-up of Correction of Myopia: Posterior Chamber Phakic Intraocular Lens With a Central Port Design

PURPOSE

To assess the long-term correction of moderate to high myopia using a posterior chamber phakic intraocular lens with a central port design.

METHODS

Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, intraocular pressure (IOP), endothelial cell density (ECD), vault, and adverse events over a 5-year period were evaluated retrospectively.

RESULTS

A total of 147 eyes (83 patients) were evaluated. Mean postoperative UDVA and CDVA were 0.05 ± 0.11 and 0.02 ± 0.08 logMAR at 1 year and 0.13 ± 0.18 and 0.02 ± 0.09 logMAR at 5 years, respectively. More than 95% of eyes achieved CDVA of 20/25 or better at both follow-up periods. CDVA was unchanged or improved from one to three or more lines in all eyes. Preoperatively, mean spherical equivalent (SE) was -9.20 ± 3.02 diopters (D). At 1 year, the mean SE was -0.17 ± 0.26 D, with 91.53% of eyes within ±0.50 D and 100% of eyes within ±1.00 D of the target. At 5 years, the mean SE was -0.44 ± 0.47 D, with 67.4% of eyes within ±0.50 D and 90.1% of eyes within ±1.00 D of the target. Mean IOP was 12.74 ± 1.65 and 13.0 ± 2.03 mm Hg, at 1 and 5 years, respectively. No significant rise in IOP (> 20 mm Hg) occurred during the follow-up period. Mean ECD was 2,696 ± 358 and 2,645 ± 359 cells/mm² at 1 and 5 years, respectively, representing a non-significant loss of 0.43% from preoperative values (P = .304). Mean vault changed significantly from 398 ± 187 µm at 1 year to 340 ± 163 µm at 5 years (P < .001). No intraoperative or postoperative complications or adverse events occurred during the follow-up period.

CONCLUSIONS

The good long-term outcomes found in this study support the use of this lens with a central port design for the correction of moderate to high myopia. [J Refract Surg. 2019;35(3):169-176.].

Three-year follow-up of intrastromal corneal ring segment implantation in central keratoconus with regular astigmatism: ‘Bow-tie’ shape

Purpose:

To assess the outcomes of implanting Ferrara-type intrastromal corneal ring segments in central ‘bow-tie’-shaped keratoconus over 3 years of follow-up.

Methods:

A total of 20 eyes with central ‘bow-tie’-shaped keratoconus were evaluated before and after implanting Ferrara-type intrastromal corneal ring segments (AJL Ophthalmic, Spain). LogMAR uncorrected distance visual acuity and best corrected distance visual acuity and residual refractive errors analysed using vector analysis were recorded preoperatively, at 6 months, 1 year, and 3 years postoperatively.

Results:

The mean uncorrected distance visual acuity (LogMAR scale) rose from a preoperative 0.75 ± 0.28 to a 6-month postoperative 0.38 ± 0.28 (p < 0.0001). The corrected distance visual acuity, in turn, improved from 0.07 ± 0.06 to 0.05 ± 0.06 (p = 0.0008). Both the uncorrected distance visual acuity and corrected distance visual acuity were stable over the postoperative period in both groups (p > 0.05). None of the eyes lost uncorrected distance visual acuity and corrected distance visual acuity lines over the postoperative follow-up period. The spherical equivalent and the refractive cylinder declined steeply after intrastromal corneal ring segments implantation (p < 0.0001). Both the spherical equivalent and refractive cylinder were stable over the postoperative period. None of the eyes had an increase in maximum or minimum keratometry greater than 0.75D over the postoperative period.

Conclusion:

The planning for intrastromal corneal ring segments insertion proposed in this study reduces the spherical equivalent and refractive cylinder in this type of keratoconus, while improving post-surgery uncorrected distance visual acuity and corrected distance visual acuity. These results remain stable over 3 years of follow-up. Therefore, this procedure could be considered as an effective therapeutic alternative in patients affected by this type of keratoconus.

Implantable collamer lens with central hole: 3-year follow-up

Purpose

To evaluate the long-term predictability, stability, safety, and efficacy of the V4c Visian implantable collamer lens (ICL) with central hole to correct myopia.

Patients and methods

One hundred and eighty-four eyes of 92 patients were evaluated during 3 years after implantation of the V4c ICL. The refraction, uncorrected distance visual acuity, best-corrected distance visual acuity, IOP, endothelial cell count, vault, and adverse effects were evaluated every 12 months during the whole follow-up.

Results

The mean spherical equivalent dropped from -8.30±2.98 D preoperatively to −0.37±0.47 D at 36 months post-surgery, with 91.8% eyes being within ±1.00 D of emmetropia. With respect to the astigmatic components J0 and J45, 98.4% and 99.5% of eyes, respectively, were within ±0.50 D of the desired refraction. At 36 months, 78.8% of eyes had no change in the Snellen lines of best-corrected distance visual acuity, while 8.7% gained one line and 6.5% gained two or more lines; mean safety and efficacy indexes were 1.03 and 0.90, respectively. Mean endothelial cell count was 2,742±340 cells/mm² before and 2,663±366 cells/mm² at 36 months post-surgery. Mean IOP reduced from 13.7±1.9 mmHg preoperatively to 12.8±1.7 mmHg at 36 months post-surgery. Mean vault varied from 409±196 µm at 12 months to 349±165 µm at 36 months.

Conclusion

The visual and refractive outcomes were very good and highly stable throughout the follow-up period, indicating that this ICL model may be predictable, stable, safe, and effective to correct myopia in the long term.

Repeatability of in-vitro optical quality measurements of intraocular lenses with a deflectometry technique effect of the toricity

AIM

To evaluate the repeatability of an optical device for measuring the Zernike coefficients of toric intraocular lenses (IOLs) and assess whether its toricity has any impact in its repeatability.

METHODS

An experienced technician used the NIMO TR1504 to measure the Zernike coefficients 30 times for an aperture of 4.50 mm for all lenses included. The IOLs included were divided into two group: toric and non-toric ones. The cylindrical powers of the toric lenses included in the present study were 1.00, 1.50, 2.25, 3.00 and 3.75 D. Finally, the repeatability of the NIMO TR1504 was described in terms of within subject standard deviation (Sw) and repeatability limit.

RESULTS

The Sw was smaller than 0.011 µm for both lens groups and all Zernike coefficients, and the difference between both groups was smaller than 0.004 µm for all Zernike coefficients. Regarding the repeatability limit, this value was smaller than 0.025 µm for the toric lens group, and smaller than 0.031 µm for the non-toric lens one for all Zernike coefficients. Furthermore, the maximum difference between both lens groups was 0.010 µm.

CONCLUSION

The repeatability of the NIMO TR1504 to measure the optical quality is high and independent of the lens toricity. These results reflect that this system is robust and could be used to measure the in-vitro optical quality of either toric or non-toric IOLs.

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.].

Bilateral Implantation of the Acri.LISA Bifocal Intraocular Lens in Myopic Eyes

Purpose

To asses visual quality after bilateral implantation of the Acri.LISA 366D intraocular lens (IOL) (Carl Zeiss Meditec) in patients with high and low–moderate myopia.

Methods

A total of 304 eyes of 152 patients had bilateral implantation of the Acri.LISA 366D IOL. The patients were divided into 2 groups: low–moderate myopia (IOL power from 15 to 20.5 D) and high myopia (IOL power from 0 to 14.5 D). Monocular and binocular best-corrected distance visual acuity (BCVA) and best distance-corrected near visual acuity (BCNVA), binocular best distance-corrected intermediate visual acuity (BCIVA), and distance contrast sensitivity (OS) under photopic (85 cd/m2) and mesopic (5 cd/m2) conditions were determined.

Results

At the 6-month postoperative visit, there were no statistically significant differences in monocular and binocular BCVA (p=0.13 and p=0.22, respectively). Monocular and binocular BCNVA was comparable between the groups (p=0.26 and p=0.09, respectively). The mean binocular BCIVA changed significantly as a function of the distance of the test (p<0.01) in both groups, and there were no statistically significant differences between groups at any distance. Monocular and binocular CS under photopic and mesopic conditions was similar between both groups (p>0.01).

Conclusions

Bilateral implantation of the Acri.LISA 366D in high myopic eyes provides a satisfactory full range of vision comparable to that obtained in low–moderate myopic eyes.

Differential Expression of Proteoglycans by Corneal Stromal Cells in Keratoconus

PURPOSE

Keratoconus is a heterogeneous disease associated with a range of pathologies, including disorders that involve proteoglycans (PGs). Some PG alterations, mainly in keratan sulfate (KS), occur in keratoconus. In this article, we studied the differential expression of the genes encoding PGs in cells isolated from keratoconus patients and healthy controls, as well as in corneal sections.

METHODS

Human central corneal tissue was obtained from cadaver donors and patients undergoing penetrating keratoplasty surgery. A transcriptomic approach was used, employing quantitative PCR, to analyze both the expression of the enzymes involved in glycosaminoglycan (GAG) biosynthesis and the PG core proteins. The expressions of the differentially expressed core proteins and of the GAG chains were also analyzed by immunocytochemistry in the cultured cells, as well as by immunohistochemistry in corneal sections.

RESULTS

The mRNA levels of most major matrix PG mRNAs in the cultured keratoconic stromal cells decreased except collagen XVIII, which increased. At keratocyte surfaces, some heparan sulfate PGs were down-regulated. With respect to GAGs, there were changes in gene expression for the polymerization of the GAG chains, mainly KS and chondroitin sulfate, and in the modification of the saccharidic chains, pointing to an alteration of the sulfation patterns of all GAG species.

CONCLUSIONS

Most of the PG core proteins underwent significant changes in cultured keratoconic cells and corneas. With regard to GAG chains, the polymerization of the chains and their chemical modification was modified in way that depended on the specific type of GAG involved.

Implantation of Implantable Collamer Lenses After Radial Keratotomy

PURPOSE

To assess the predictability, efficacy, and safety of posterior chamber phakic implantable collamer lens (ICL) implantation after radial keratotomy.

METHODS

In a retrospective non-comparative interventional case series, outcomes in 6 consecutive eyes of 4 patients with residual refraction after radial keratotomy were analyzed after the implantation of ICLs. All of the lenses were implanted to correct the residual refractive error, ranging from -12.00 to +3.50 diopters (D) for sphere and from -0.75 to -3.75 D for cylinder.

RESULTS

The mean uncorrected distance visual acuity after ICL implantation was 0.31 ± 0.36 logMAR and the corrected distance visual acuity was 0.12 ± 0.10 logMAR. The mean efficacy index was 0.86. No eyes lost lines of visual acuity, two eyes did not change after surgery, two eyes gained one line, and two eyes gained two lines. The mean safety index was 1.17. No intraoperative complications were found and ICL explantation or repositioning was not required during the follow-up. No cases of cataract, pigment dispersion glaucoma, pupillary block, or other vision-threatening complications were found.

CONCLUSIONS

ICL implantation may be considered a reasonable surgical procedure for correcting residual refractive errors after radial keratotomy. [J Refract Surg. 2017;33(6):395-398.].

Different Use of Cell Surface Glycosaminoglycans As Adherence Receptors to Corneal Cells by Gram Positive and Gram Negative Pathogens

The epithelium of the cornea is continuously exposed to pathogens, and adhesion to epithelial cells is regarded as an essential first step in bacterial pathogenesis. In this article, the involvement of glycosaminoglycans in the adhesion of various pathogenic bacteria to corneal epithelial cells is analyzed. All microorganisms use glycosaminoglycans as receptors, but arranged in different patterns depending on the Gram-type of the bacterium. The heparan sulfate chains of syndecans are the main receptors, though other molecular species also seem to be involved, particularly in Gram-negative bacteria. Adherence is inhibited differentially by peptides, including heparin binding sequences, indicating the participation of various groups of Gram-positive, and -negative adhesins. The length of the saccharides produces a major effect, and low molecular weight chains inhibit the binding of Gram-negative microorganisms but increase the adherence of Gram-positives. Pathogen adhesion appears to occur preferentially through sulfated domains, and is very dependent on N- and 6-O-sulfation of the glucosamine residue and, to a lesser extent, 2-O sulfation of uronic acid. These data show the differential use of corneal receptors, which could facilitate the development of new anti-infective strategies.

Posterior chamber collagen copolymer phakic intraocular lens with a central hole to correct myopia: One-year follow-up

PURPOSE

To assess the predictability, stability, efficacy, and safety of a newly developed posterior chamber phakic intraocular lens (pIOL) (model V4c Visian Implantable Collamer Lens) to correct moderate to high myopia.

SETTING

Fernández-Vega Ophthalmological Institute, Oviedo, Spain.

DESIGN

Prospective case series.

METHODS

This study evaluated eyes that had implantation of the new pIOL model with a central hole for myopia correction. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, intraocular pressure (IOP), endothelial cell density, pIOL vault, and adverse events were evaluated over 12 months.

RESULTS

The study comprised 147 eyes of 80 patients. Preoperatively, the mean spherical equivalent (SE) was -8.80 diopters (D) ± 2.60 (SD). At 12 months, the mean SE was -0.14 ± 0.26 D, with 93.9% of eyes within ±0.50 D of the target and 100% of eyes within ±1.00 D. The mean UDVA and CDVA were 0.028 ± 0.055 logMAR and 0.003 ± 0.013 logMAR, respectively. The efficacy and safety indices were 1.00 and 1.04, respectively. All eyes had unchanged CDVA or gained 1 or more lines during the follow-up. The IOP remained stable over time; no eye developed anterior subcapsular cataract. Twelve months postoperatively, the mean vault was 405.5 ± 184.7 μm (range 100 to 980 μm), and the mean endothelial cell loss was 1.7%.

CONCLUSION

The good refractive and visual acuity outcomes and the highly stable IOP values obtained over 12 months support the use of the new pIOL model with a central hole for the correction of moderate to high myopia.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Five-year functional outcomes and vault of -20 diopter myopic phakic intraocular lens implantation

PURPOSE

To evaluate refractive and visual outcomes and complications associated with phakic intraocular lens (pIOL) implantation to correct high myopia.

SETTINGS

Fernández-Vega Ophthalmological Institute, Oviedo, Spain.

DESIGN

Retrospective observational case series.

METHODS

Uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA), refraction, vault, and adverse effects were evaluated after 5 years with Visian ICMV4 pIOL.

RESULTS

Mean spherical equivalent (SE) dropped from -18.32 ± 2.37 diopters (D) preoperatively to -0.88 ± 0.52D 5 years postoperatively; 61% of eyes were within ±0.75 D of the target. The mean Snellen decimal CDVA and UDVA were 0.73 ± 0.23 and 0.55 ± 0.26, respectively. More than 50% of eyes achieved 20/25 or better CDVA postoperatively. Four eyes had lost 2 or 1 lines of CDVA, 10 eyes had not lost any lines from preoperatively, and 46 eyes had gained 1 or more lines of CDVA 5 years postoperatively. The safety index was 1.26 ± 0.32. Forty eyes had UDVA of 20/40 or better postoperatively. The efficacy index was 0.99 ± 0.42. At 5-year follow-up, the mean central vault was 475.28 ± 216.38 μm. No eyes showed central contact between the pIOL and crystalline lens. Nevertheless, 10 eyes showed peripheral contact with a central vault between 150 and 260 μm. Two eyes developed anterior subcapsular cataract, although only 1 eye required cataract surgery.

CONCLUSIONS

Predictability, safety and effective outcomes of posterior pIOL of (- were good, as well as postoperative complications over the long term. A central vault of 260 μm was enough to prevent the peripheral contact between the pIOL and crystalline lens in eyes with high myopia.

FINANCIAL DISCLOSURE

The authors have no proprietary interest in any of the materials mentioned in this article.

Prevalence of cataract after collagen copolymer phakic intraocular lens implantation for myopia, hyperopia, and astigmatism

PURPOSE

To evaluate the prevalence of cataract after Implantable Collamer Lens phakic intraocular lens (pIOL) implantation with different models at different ages and for different refractive powers.

SETTING

Fernández-Vega Ophthalmological Institute, Oviedo, Spain.

DESIGN

Retrospective nonrandomized clinical study.

METHODS

The pIOL (models V4, V4b, or V4c) was implanted in all cases.

RESULTS

The study included 3420 eyes (1898 patients). The mean patient age at surgery was 31.2 years ± 6.4 (SD) (range 18 to 50 years) and the mean spherical refractive error, -7.27 ± 5.24 diopters (D) (range -26.5 to 12.5 D). Twenty-one eyes (0.61%) of 15 patients had pIOL explantation (all model V4) because cataract developed. The mean age of the patients who had explantation was 39.43 ± 4.57 years; 7 were younger than 40 years, and 8 were 40 years or older. The mean spherical equivalent was -10.1 ± 5.41 D; 3 eyes had a pIOL power less than -10.50 D, 4 eyes between -10.50 D and -13.50 D, and 14 higher than -13.50 D. The mean time between pIOL implantation and cataract surgery was 4.2 ± 1.8 years. No eye with implantation of the latest models (V4b and V4c) developed cataract. The mean vault distance in eyes that developed cataracts was 103 ± 69 μm.

CONCLUSIONS

The incidence of cataract was low after pIOL implantation at the 6-year follow-up. The rate of cataract was higher in older patients and in those with high refractive errors.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.