Deep anterior lamellar keratoplasty for keratoconus: Elements for success

Advanced keratoconus may require keratoplasty when the patient can no longer achieve functional vision with glasses and contact lenses. Deep anterior lamellar keratoplasty (DALK) has become the surgical treatment of choice due to its undisputed advantages over penetrating keratoplasty including the reduced risk of intraoperative complications, the absence of endothelial immune rejection, and the longer graft survival. Albeit "big-bubble" DALK still represents the most popular surgical method, several modifications have been developed over the years. This allowed standardization of the technique, with improved success rates and clinical outcomes. This review presents an overview on the literature on DALK surgery for keratoconus. We discuss state-of-the art surgical techniques, current evidence on the clinical outcomes and complications as well as possible future directions

Intravitreal Dexamethasone Implant in Patients Who Did Not Complete Anti-VEGF Loading Dose During the COVID-19 Pandemic: a Retrospective Observational Study

Introduction To compare the functional and anatomic outcomes between eyes in patients with diabetic macular edema (DME) who underwent a complete anti-vascular endothelial growth factor (VEGF) loading dose with aflibercept and those who were switched to dexamethasone intravitreal (DEX) implant after an incomplete anti-VEGF treatment regimen during the coronavirus disease 2019 (COVID-19) pandemic. Methods This was a retrospective and comparative study conducted on patients with DME. Main outcome measures were mean change in best corrected visual acuity (BCVA) and central retinal thickness (CRT) from baseline to month 4. Results Forty-three eyes (23 eyes in the anti-VEGF group and 20 eyes in the DEX group) were included. Mean BCVA significantly improved from 37.7 +/- 25.3 and 35.7 +/- 22.0 letters at baseline to 45.4 (23.9) (mean adjusted BCVA improvement 7.6 +/- 20.8 letters, p = 0.033) and 46.1 +/- 26.0 (mean adjusted BCVA improvement 10.6 +/- 15.9 letters, p = 0.049) at month 4 in the anti-VEGF and DEX groups, respectively, with no significant differences between study groups (mean adjusted BCVA difference 2.8 letters, 95% CI - 9.4 to 14.9 letters, p = 0.648). There were no statistically significant differences in the proportion of eyes that achieved a BCVA improvement of >= 5, >= 10, and >= 15 letters between groups. CRT was significantly reduced from baseline to month 4 in both DEX (mean adjusted CRT reduction 167.3 +/- 148.2 mu m, p = 0.012) and anti-VEGF groups (mean adjusted CRT reduction 109.9 +/- 181.9 mu m, p < 0.001), with no differences between them (mean adjusted CRT difference 56.1 mu m, 95% CI - 46.0 to 158.2 mu m, p = 0.273). Of 20 eyes in the DEX group, 16 (80.0%) and 9 (45.0%) eyes achieved a CRT reduction of >= 20% from baseline at 2 months and at 4 months, respectively. Conclusions Our results seem to suggest that DEX implant can significantly improve both functional and anatomic clinical outcomes in patients who were unable to complete anti-VEGF loading dose during the COVID-19 pandemic

Comment on: "Descemet-Stripping Automated Endothelial Keratoplasty Centration and Interface Folds: Surgical Management"

No abstract availabl

September consultation #2

Currently, the standard approach for managing epithelial ingrowth involves lifting of the LASIK flap followed by removal of the ingrowth through mechanical debridement. However, 30 years after surgery, safely lifting the LASIK flap without causing tears or damaging the flap may prove quite challenging

Re: Singh et al.: Vaccine-associated uveitis following COVID-19 vaccination: vaccine adverse event reporting system database analysis (Ophthalmology. 2023;130:179-186)

Although the VAERS database represents an essential tool for pharmacovigilance and its analysis allows prompt identification of safety signals and due consideration of serious vaccine side effects, higher levels of evidence would still be required to definitively establish causation. As we await more epidemiological data, we agree with the authors that it remains prudent to distinguish the observed temporal relationship from a true causal association.

Large-Diameter Modified Big-Bubble Deep Anterior Lamellar Keratoplasty in Post-Radial Keratotomy Eyes

PURPOSE: To report the outcomes of our modified large-diameter (9-mm) big-bubble deep anterior lamellar keratoplasty (DALK) technique with improved success rates of pneumatic dissection in post-radial keratotomy (RK) eyes.DESIGN: Retrospective case series.METHODS: At Ospedali Privati Forli, "Villa Igea," Forli, Italy., modified big-bubble DALK was performed in consecutive post-RK eyes. The technique included large-diameter (9-mm) deep partial-thickness trephination based on the thinnest anterior segment optical coherence tomography pachymetry value at 9 mm, air injection through a cannula advanced 2 mm centripetally from the base of the trephination, limited stromal clearance of the central 6-mm optical zone, and suturing of a 9-mm anterior lamellar graft prepared by microkeratome dissection. Success rate of pneumatic dissection, corrected distance visual acuity (CDVA), keratometric astigmatism, and complications were recorded.RESULTS: Eight eyes of 7 patients were included. Pneumatic dissection succeeded in 7 cases (87.5%). CDVA significantly improved from 0.94 +/- 0.43 to 0.14 +/- 0.06 logMAR (P <.001). All eyes reached Snellen CDVA >= 20/40, whereas 3 eyes (37.5%) reached >= 20/25. At the last follow-up, 5 eyes (62.5%) had a final keratometric astigmatism <= 4 diopters, whereas 2 eyes (25.0%) had <= 2 diopters.CONCLUSION: Big-bubble DALK can be successfully performed in post-RK eyes with our standardized technique. (c) 2022 Elsevier Inc. All rights reserved

Twenty-Two-Year Clinical Outcome of a Case of Endokeratoplasty

Purpose:The purpose of this study was to report the 22-year clinical outcome of a patient who underwent endokeratoplasty.Methods:To report the clinical outcomes of 37-year-old male who underwent endokeratoplasty for decompensated Fuchs endothelial dystrophy in 1998.Results:After subsequent cataract surgery and iridoplasty, at 22 years post endokeratoplasty, the Snellen best spectacle-corrected visual acuity is 20/20 (-5.50 sphere -3.00 cylinder at 135 degrees), endothelial cell count is 645 cells/mm2, central corneal thickness is 644 m, and the cornea remains clear with no evidence of graft rejection or failure.Conclusions:To the best of our knowledge, this is the longest reported outcome for selective endothelial replacement. The patient undergoing endokeratoplasty can achieve an excellent visual acuity and long-term graft survival

Microscope-Integrated Intraoperative Optical Coherence Tomography-Guided Big-Bubble Deep Anterior Lamellar Keratoplasty

Purpose: The purpose of this study was to evaluate the feasibility of microscope-integrated intraoperative optical coherence tomography (OCT) for real-time quantitative analysis of surgical planes in big-bubble deep anterior lamellar keratoplasty (DALK). Methods: In this interventional case series, intraoperative OCT-guided big-bubble DALK was performed in 16 consecutive eyes of 16 patients with keratoconus. Trephination depth was measured using the intraoperative OCT caliper tool. Aiming for a depth within 150 mu m from the endothelial surface, the trephination groove was extended to a deeper plane using a 15-degree blade. Repeat OCT scans were taken to measure residual stromal thickness before insertion of the DALK probe from the bottom of the extended trephination. Caliper measurements, success rate of pneumatic dissection, and complications were recorded. Results: After trephination, residual stromal thickness exceeded 150 mu m in all eyes and averaged 257.1 +/- 42.5 mu m. In each case, the initial trephination groove was extended to a depth within 150 mu m from the endothelial surface (118.9 +/- 27.1 mu m). Big-bubble formation was achieved in 12 eyes (75%). Type 1 bubble was obtained in 11 eyes. Perforation requiring conversion to penetrating keratoplasty occurred in 4 eyes during insertion of the cannula into a residual stromal bed of <100 mu m (n = 2; 63 and 75 mu m) or layer-by-layer dissection (n = 2). Conclusions: Quantitative analysis of intraoperative OCT scans can be used to assist decision-making on whether to proceed with pneumatic dissection or extend the trephination groove, thereby facilitating insertion of the injection cannula at the desired stromal depth