Scleral contact lenses for visual rehabilitation in keratoconus and irregular astigmatism after refractive surgery

AbstractThis study aims to report our experience of using fluid-ventilated, gas-permeable scleral contact lenses (SCLs) for visual rehabilitation of patients with keratoconus and irregular astigmatism after refractive surgery. This is a noncomparative interventional case series reporting eight consecutive patients fitted with SCLs because of irregular astigmatism following the failure of other optical corrections. Retrospective chart review and data analysis included age, sex, etiology prior to lens fitting, visual outcomes, follow-up time, and complications. Twelve eyes of eight patients were studied. All eyes were fitted with SCLs due to unsatisfactory vision with spectacle correction or other contact lens modalities. Five eyes had keratoconus and seven had irregular corneas post refractive surgery. The mean follow-up period was 14.4 ± 1.3 months (range 11–17 months). The mean age was 32.63 ± 7.68 years (range 18–48 years). The average steepest keratometry(Kmax) of our series was 49.56 ± 12.2 D. The mean refractive astigmatism was 5.50 ± 5.3 D. The mean best corrected visual acuity (BCVA) in logarithm of the minimum angle of resolution improved from 0.71 ± 0.50 (range 0.10–1.40) to 0.05 ± 0.07 (range 0.00–0.15) after SCL fitting (p < 0.001). All reported eyes achieved significant improvement in the BCVA with SCL fitting. None of the patients discontinued to wear SCLs. SCLs should be considered lenses of choice in irregular corneas refractory to conventional optical correction

Long-Term Results after DMEK (Descemet’s Membrane Endothelial Keratoplasty)

Ziel der Arbeit: Evaluation der langfristigen Ergebnisse sowie der Komplikationsrate nach Descemet’s Membran Endothelialen Keratoplastik (DMEK) Methoden: Eine cross-sectional, Fall-Serien Studie. Insgesamt wurden 230 Augen von 142 Patienten, die zwischen 2010 und 2014 eine DMEK an der Universitäts-Augenklinik Marburg bekommen haben, untersucht. Die best-korrigierte Sehschärfe (BCVA), die Refraktion, die zentrale Hornhautdicke, das Hornhautvolumen sowie die Endothelialzelldichte wurden als Parameter herangezogen und mit den präoperativen Befunden verglichen. Die Transplantat-Überlebensrate sowie die postoperativen Komplikationen wurden ebenfalls betrachtet. Ergebnisse: Die Nachbeobachtungszeit betrug 47 ± 13.3 Monate. Bei den Patienten die keine anderen okuläre Erkrankungen hatten hat sich die BCVA von 0.60 ± 0.32 logMAR präoperativ auf bis zu 0.10 ± 0.22 logMAR verbessert (201 Augen). 71.1% dieser Patienten hatten eine BCVA von 0.11 logMAR oder besser (≥ 0.8 dezimal), wobei 49.2% dieser Patienten eine volle BCVA von 0.00 logMAR oder besser erreicht haben. Die zentrale Hornhautdicke hat von 675 ± 112µm präoperativ auf 547 ± 52 µm in der letzten Follow-up Untersuchung abgenommen, und das Hornhautvolumen hat von 65.2 ± 8.4 mm2 präoperativ auf 61.9 ± 5.4 mm2 abgenommen. Der Endothelzellverlust lag bei 1392 ± 455 Zellen/mm², was einem durchschnittlichen Verlust von 54.7% der Transplantatzellen entspricht. Die Transplantat-Überlebensrate lag bei 92% mit einer durchschnittlichen Überlebenszeit von 76.6 ± 1.3 Monaten. Schlussfolgerung: DMEK bietet hohe visuelle Ergebnisse und sehr gute klinische Befunde, die mehrere Jahre nach der Operation stabil bleiben können. Durch die hohe Transplantat-Überlebensrate und die niedrige postoperative Komplikationsrate wird DMEK derzeit als erste Wahl zur Behandlung von Endothelzellerkrankungen eingesetzt

Visual outcomes of topography-guided excimer laser surgery for treatment of patients with irregular astigmatism

The aim of this study was to evaluate the efficacy, safety, and predictability of topography-guided treatments to enhance refractive status following other corneal surgical procedures. In a prospective case series study, 28 consecutive eyes of 26 patients with irregular astigmatism after radial keratotomy, corneal transplant, small hyperopic and myopic excimer laser optical zones, and corneal scars were operated. Laser-assisted in situ keratomileusis (LASIK) (n = 8) and photorefractive keratectomy (PRK) (n = 20) were performed using the ALLEGRETTO WAVE excimer laser and topography-guided customized ablation treatment software. Preoperative and postoperative uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), manifest and cycloplegic refraction, and corneal topography with asphericity were analyzed in 12 months follow-up. Uncorrected visual acuity (UCVA) changed from 0.2 +/- 0.2 or (20/100 +/- 20/100) to 0.51 +/- 0.31 or (20/40 +/- 20/60) in the LASIK group (P = 0.01) and from 0.34 +/- 0.16 or (20/60 +/- 20/120) to 0.5 +/- 0.23 or (20/40 +/- 20/80) in the PRK group (P = 0.01). Refractive cylinder decreased from -3.2 +/- 0.84 diopters (D) to -2.06 +/- 0.42 D in the LASIK group (P = 0.07) and from -2.25 +/- 0.39 D to -1.5 +/- 0.23 D in the PRK group (P = 0.008). Best corrected visual acuity did not change significantly in either group. Topography-guided treatment is effective in correcting the irregular astigmatism after refractive surgery. Topography-guided PRK can significantly reduce irregular astigmatism and increase the UCVA and BCVA

Myoring implantation alone versus corneal collagen cross-linking following myoring implantation for management of keratoconus: 1 year follow up

Purpose: To compare combined MyoRing implantation with previously corneal collagen cross-linking (CXL- MyoRing) versus MyoRing implantation alone in patients with keratoconus. Methods: This retrospective, comparative, cohort study included 33 eyes of 33 patients with keratoconus stage II and III according to Amsler-Krumeich classification. Two groups were performed for this study with 1 year follow up. The group 1 received MyoRing implantation and the group 2 received CXL approximately 12 months before MyoRing implantation. All patients had a complete pre and post-operative examination including visual, refractive and keratometry examinations. Results: In Group 1 at the end of follow up the mean UDVA and CDVA improved by 9 and 4 lines of logMAR. In Group 2 the mean UDVA and CDVA improved by 8 and 2 lines of logMAR. There was not observed a statistically significant difference between mean UDVA of two groups postoperatively (p = 0.142) whereas the mean CDVA in Group 2 was significantly better than mean Group 1 at the end of follow up (p= 0.018). Spherical equivalent error and refractive astigmatism were significantly reduced in both groups which no statistically significant differences was noted in these refractive parameters between two groups. The mean keratometric values also were reduced in both groups at the end of follow up which no statistically significant difference was observed between two groups. Conclusion: Both MyoRing implantation alone and combined MyoRing implantation with previously CXL were safe and effective methods for moderate and severe keratoconus and resulted in similar clinical outcomes after one year follow up. ExclusivelyMyoRing implantation alone demonstrated better outcome in mean CDVA

Pentacam-based phototherapeutic keratectomy outcome in superficial corneal opacities

Mohammad A RashadOphthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, EgyptPurpose: This study aimed to evaluate the effectiveness of phototherapeutic keratectomy (PTK) as an alternative treatment to keratoplasty using the Pentacam to assess depth of dense opacities.Methodology: PTK was performed in eleven eyes of ten patients with superficial corneal opacities after assessment by Scheimpflug images of the Pentacam for central corneal thickness (CCT) and opacity level and depth.Results: The best-corrected spectacle visual acuity (BCSVA) significantly improved. The preoperative mean logMAR was 0.85 (0.14 decimal equivalent, 6/42 Snellen&amp;#39;s equivalent), and the final postoperative mean logMAR was 0.58 (0.26 decimal equivalent, 6/23 Snellen&amp;#39;s equivalent). The mean preoperative CCT was 465.64 &amp;plusmn; 71.94 &amp;micro;m. The mean programmed ablation depth was 142.09 &amp;plusmn; 47.58 &amp;micro;m. The programmed ablation depth was correlated to mean logMAR early (1 month) and not correlated later (6 months). None of the eyes lost lines of BCSVA or developed serious complications, such as keratectasia, delayed epithelialization, or corneal melting.Conclusion: Corneal scars extending beyond the anterior one-fifth of the cornea can be treated safely and effectively by PTK due to the smoothing effect, with reduction of the cylinder rather than complete opacity removal. This can decrease the need for keratoplasty.Keywords: phototherapeutic keratectomy, PTK, corneal opacities, Pentaca

Clinical performance of a new hybrid contact lens for keratoconus

Objectives: To compare the clinical performance of the Clearkone hybrid contact lens for the treatment of keratoconus against the habitual contact lens of the patients. Methods: A total of 33 eyes from 18 patients were fitted with the Clearkone. High- and low-contrast visual acuity (HCVA and LCVA), central corneal thickness (CCT), and contrast sensitivity acuity (CSF) were recorded with habitual lenses (prestudy visit) and after 1 week, 15 days, and 1 month of wear of prescribed Clearkone. Subjective vision and comfort were rated using visual analogue scales (VAS). Results: Three patients discontinued the study, one because of diffuse corneal staining after 1 day of use and the other two because of extreme discomfort. The rest of the patients completed the 1-month study. High contrast visual acuity and LCVA (logMAR) improved significantly from 0.16 6 0.12 and 0.44 6 0.22, respectively, with the patient’s habitual contact lenses to 20.006 6 0.058 and 0.23 6 0.13 after 1 day wearing Clearkone, remaining significant during all follow-up visits (P,0.001; repeated measures analysis of variance [RM-ANOVA]). There were no statistically significant differences in the mean CCT. The improvement of CSF was statistically significant with hybrid contact lenses prescribed compared with the patient’s habitual contact lenses (P,0.001; RM-ANOVA test). Improvement in VAS score, with prescribed Clearkone, was statistically significant for comfort (P=0.043; RM-ANOVA test), but not for the subjective vision (P=0.759; RM-ANOVA test). Conclusions: Clearkone provides an improvement in visual acuity, contrast sensitivity, and subjective comfort in patients with keratoconus when compared with other contact lens options. However, clinicians must get specific training to fit the lens and be aware of potential adverse event

Femtosecond laser-assisted Cvintal topoplasty

We present a case of late high progressive astigmatism following penetrating keratoplasty for keratoconus, which was associated with peripheral thinning in the donor-receptor area, which may be recognized as recurrence of ectasia. Treatment was accomplished with Cvintal's Topoplasty assisted by femtosecond laser for a top hat, followed by resuture with peroperative adjustment guided by ceratoscopy.Apresentamos um relato de astigmatismo tardio progressivo pós-transplante de córnea para ceratocone, associado à afinamento periférico na junção doador-receptor, o que presumidamente pode ser considerado como recorrência da ectasia. O caso foi tratado por meio de Topoplastia de Cvintal assistida por laser de femtossegundo para a confecção da incisão com geometria top hat, seguido de sutura com ajuste per-operatório guiado por ceratoscopia.Instituto Benjamin Constant Serviço de OftalmologiaInstituto Benjamin Constant Setor de CórneaInstituto de Olhos Renato AmbrósioUniversidade Federal de São Paulo (UNIFESP) OftalmologiaUNIFESP, OftalmologiaSciEL

Eccentric lamellar keratolimbal grafts harvested with a manually guided microkeratome

Background: To perform lamellar keratolimbal allograft transplantation in a one- step procedure with a single graft, we investigated the feasibility of harvesting eccentric lamellar keratolimbal grafts from conventionally processed corneoscleral buttons using a manually guided microkeratome in conjunction with an artificial anterior chamber system. Methods: We used the Moria LSK- One microkeratome and the automated lamellar therapeutic keratoplasty ( ALTK) system ( Antony, France). Ten human donor eyes were used to obtain single- piece lamellar keratolimbal grafts. Specimens were processed for light and electron microscopy. Results: Eccentric keratolimbal grafts could be obtained from all human donor buttons. Grafts include a crescent- shaped limbal and a large corneal portion. No visible damage to the limbal region was discernible. Conclusion: Our data show that the LSK- One microkeratome in conjunction with the ALTK system allows harvesting eccentric keratolimbal grafts from donor corneoscleral buttons. Copyright (c) 2007 S. Karger AG, Basel

Nonsurgical Procedures for Keratoconus Management

Objectives. To describe the past 20 years’ correction modalities for keratoconus and their visual outcomes and possible complications. Methods. A review of the published literature related to the visual outcomes and possible complications in the context of keratoconus management using nonsurgical procedures for the last 20 years (glasses and contact lenses) was performed. Original articles that reported the outcome of any correction modalities of keratoconus management were reviewed. Results. The most nonsurgical procedure used on keratoconus management is the contact lens fitting. Soft contact lenses and soft toric contact lenses, rigid gas-permeable contact lenses, piggyback contact lens system, hybrid contact lenses, and scleral and corneoscleral contact lenses form the contemporary range of available lens types for keratoconus management with contact lenses. All of them try to restore the vision, improve the quality of life, and delay surgical procedures in patients with this disease. Complications are derived from the intolerance of using contact lens, and the use of each depends on keratoconus severity. Conclusions. In the context of nonsurgical procedures, the use of contact lenses for the management of keratoconic patients represents a good alternative to restore vision and improve the quality of live in this population