IC3D Classification of Corneal Dystrophies-Edition 3.

PURPOSE: The International Committee for the Classification of Corneal Dystrophies (IC3D) was created in 2005 to develop a new classification system integrating current information on phenotype, histopathology, and genetic analysis. This update is the third edition of the IC3D nomenclature. METHODS: Peer-reviewed publications from 2014 to 2023 were evaluated. The new information was used to update the anatomic classification and each of the 22 standardized templates including the level of evidence for being a corneal dystrophy [from category 1 (most evidence) to category 4 (least evidence)]. RESULTS: Epithelial recurrent erosion dystrophies now include epithelial recurrent erosion dystrophy, category 1 ( COL17A1 mutations, chromosome 10). Signs and symptoms are similar to Franceschetti corneal dystrophy, dystrophia Smolandiensis, and dystrophia Helsinglandica, category 4. Lisch epithelial corneal dystrophy, previously reported as X-linked, has been discovered to be autosomal dominant ( MCOLN1 mutations, chromosome 19). Classic lattice corneal dystrophy (LCD) results from TGFBI R124C mutation. The LCD variant group has over 80 dystrophies with non-R124C TGFBI mutations, amyloid deposition, and often similar phenotypes to classic LCD. We propose a new nomenclature for specific LCD pathogenic variants by appending the mutation using 1-letter amino acid abbreviations to LCD. Pre-Descemet corneal dystrophies include category 1, autosomal dominant, punctiform and polychromatic pre-Descemet corneal dystrophy (PPPCD) ( PRDX3 mutations, chromosome 10). Typically asymptomatic, it can be distinguished phenotypically from pre-Descemet corneal dystrophy, category 4. We include a corneal dystrophy management table. CONCLUSIONS: The IC3D third edition provides a current summary of corneal dystrophy information. The article is available online at https://corneasociety.org/publications/ic3d .

Infectious keratitis following corneal transplantation: A long-term cohort study.

BACKGROUND: To assess the long-term incidence and risk factors for post-keratoplasty infectious keratitis (IK), associated ocular pathogens, and antibiotic resistance profiles. METHODS: Cohort study including 2553 consecutive penetrating, endothelial, and anterior lamellar keratoplasties performed between 1992 and 2020. Medical and microbiological records of patients clinically diagnosed with IK were retrospectively reviewed. MAIN OUTCOME MEASURES: cumulative incidence of IK, infectious agent species, and antibiotics resistance profiles. RESULTS: The average follow-up time after transplantation was 112 ± 96 months. Eighty-nine IK episodes were recorded; microbiological tests were positive in 55/89 (62%). The cumulated incidence of postoperative IK was 5.50%/10.25% at 10/20 years. The occurrence of at least one episode of IK after transplantation was associated with lower graft survival in the long term (p < 0.0001). Rejection risk (adjusted Hazard Ratio, 2.29) and postoperative epithelial complications (HR, 3.44) were significantly and independently associated with a higher incidence of postoperative IK. Infectious agents included 41 bacteria, 10 HSV, 6 fungi, and 1 Acanthamoeba. The rate of antibiotic resistance was 0% for vancomycin, 13% for fluoroquinolones, 20% for rifamycin, 59% for aminoglycosides, and 73% for ticarcillin. In 41% of cases, patients were under prophylactic topical antibiotics before the infectious episode. Topical antibiotics were significantly associated with increased resistance to penicillin, carbapenems, and aminoglycosides. CONCLUSION: IK (mainly bacterial) is a frequent complication of corneal transplantation in the long term. Vancomycin and fluoroquinolones can be considered as first-line treatments. Prolonged postoperative antibiotic preventive treatment is not advisable as it may increase antibiotic resistance.

Comparison of optical aberrations in keratoconus with scleral versus rigid gas permeable lenses.

PURPOSE: to assess optical aberrations under scleral (SL) versus rigid gas permeable (RGP) lenses in patients with keratoconus. METHODS: A prospective study including 25 eyes of 14 patients. The best-corrected visual acuity (BCVA) with corrective glasses, RGP and SL, stage of keratoconus (Amsler-Krumeich classification), minimum pachymetry, maximum keratometry, and corneal higher-order aberrations (i.e, total HOAs, coma, and trefoil) with RGP and with SL were collected. Aberrometry was performed using iTrace® aberrometer (Tracey Technologies, USA). RESULTS: 80% of the included keratoconus patients were stage 4, with a mean age of 34.3 years (±8.8). There were no significant differences in mean BCVA (logMAR) between SL and RGP. The mean BCVAs were significantly better both with SL (p < 0.0001) and RGP (p < 0.0001) compared with corrective glasses. Total HOAs (p = 0.01), coma (p = 0.003) and trefoil (p = 0.008) were significantly lower with SL compared with RGP. The BCVA decreased with the stage of keratoconus in SL (p = 0.01) and RGP (p = 0.02). The BCVA decreased with decreasing minimum pachymetry in SL (p = 0.02) and RGP (p = 0.002), and with increasing maximum keratometry in SL (p = 0.02) and RGP (p = 0.01). Significant correlations were found between BCVA, total HOAs (p = 0.008), and coma (p = 0.02) in SL. CONCLUSION: For the same keratoconus patients, total higher order, coma and trefoil optical aberrations were reduced with scleral lenses compared to rigid gas permeable lenses.

Freeze-dried amniotic membrane graft with a spongy layer in bilateral peripheral ulcerative keratitis: a case report.

BACKGROUND: Peripheral ulcerative keratitis (PUK) is a group of inflammatory corneal ulcers with stromal thinning and peripheral localization. Amniotic membranes (AM) are used for their anti-inflammatory and healing properties. A freeze-drying process now allows maintaining the AM viable for a long time at room temperature without altering its physical, biological, and morphologic characteristics. The effectiveness of spongy freeze-dried amniotic membrane (FD-AM) graft with multimodal imaging in the management of severe corneal thinning PUK has not been reported. CASE PRESENTATION: A 67-year-old Caribbean man histologically diagnosed with ulcerative colitis, was referred to our tertiary eye care center for a deep nasal juxtalimbal ulcer of the left eye. He was treated with topical steroids and antibiotics, methylprednisolone pulses, and oral prednisone. Due to continuous stromal thinning with 100 µm of residual corneal thickness, the decision was made to perform surgery. Conjunctival resection, inlay and overlay spongy FD-AM (Visio Amtrix® S, Tissue Bank of France, FR) were performed to preserve globe integrity. Despite tapering off oral steroids, PUK developed in the fellow eye on the 2 months follow-up. Treatment with human monoclonal antibody against tumor necrosis factor-alpha was initiated to control the active underlying inflammation. Six months following surgery, the ulcer was healed and corneal thickness in front of the former ulceration was measured at 525 µm on anterior segment-optical coherence tomography. Confocal microscopy confirmed the integration of the amniotic membrane between the corneal epithelium and the anterior stroma. CONCLUSION: Transplantation of FD-AM with a spongy layer was associated with restoration of normal corneal thickness in the PUK area. It seems to be a safe, effective, and easily accessible solution for the surgical management of PUK with impending perforation.

Efficacy, Safety, and Outcomes following Accelerated and Iontophoresis Corneal Crosslinking in Progressive Keratoconus.

PURPOSE: To investigate the outcomes of accelerated (A-CXL) and iontophoresis (I-CXL) corneal crosslinking in a large retrospective cohort with progressive keratoconus. METHODS: This retrospective observational cohort study included consecutive patients treated by A-CXL (9 mW/5.4 J/cm2) or I-CXL with a minimal follow-up of 12 months. Visual acuity, manifest refraction, topography, specular microscopy, and corneal optical coherence tomography (OCT) were evaluated at baseline and at the last visit. Progression was defined as an increase in the maximum topographic keratometry (Kmax) of 1D. RESULTS: 302 eyes of 241 patients with a mean age of 25.2 ± 7.5 years were included from 2012 to 2019: 231 and 71 eyes in the A-CXL and I-CXL groups, respectively. The mean follow-up was 27.2 ± 13.2 months (maximum: 85.7 months). Preoperatively, the mean Kmax was 51.8 ± 4.0D, with no differences between groups. Mean topographic measurements and spherical equivalent remained stable during the follow-up. At the last visit, CXL failure was reported in 60 eyes (19.9%): 40 (14.7%) versus 20 (28.2%) in A-CXL versus I-CXL, respectively, p = 0.005. The likelihood of progression after CXL was significantly higher following I-CXL: RR = 1.62, CI95 = [1.02 to 2.59], p = 0.04. Demarcation line presence at 1 month was positively correlated with higher efficacy of CXL, p = 0.03. No endothelial damage was reported, especially in 51 thin corneas (range = 342-399 µm). CONCLUSIONS: A-CXL seems more effective than I-CXL in stabilizing keratoconus; this is to be taken into account when a therapeutic indication is posed according to the aggressiveness of the keratoconus.

Asymmetric Intrastromal Corneal Ring Segments with Progressive Base Width and Thickness for Keratoconus: Evaluation of Efficacy and Analysis of Epithelial Remodeling.

Purpose: The aim of this study is to describe visual outcomes and epithelial remodeling following the implantation of asymmetric intracorneal ring segments (ICRSs) of variable thickness and base width for the management of duck-type keratoconus. Methods: A prospective observational study of patients with duck-type keratoconus was conducted. All patients received one ICRS AJL PRO + implant (AJL Ophthalmic). We analyzed demographic and clinical data, anterior segment optical coherence tomography (AS-OCT) data and Scheimpflug camera images obtained with a Placido disc MS-39 (CSO, Firenze, Italy) one and six months after surgery to determine keratometric and aberrometric outcomes and epithelial remodeling. Results: We studied 33 keratoconic eyes. ICRS implantation significantly improved both corrected distance visual acuity (CDVA) and uncorrected distance visual acuity at six months, as assessed with the logMAR (minimum angle of resolution) system, from 0.32 ± 0.19 to 0.12 ± 0.12 (p < 0.001) and from 0.75 ± 0.38 to 0.37 ± 0.24 (p < 0.001), respectively. Overall, 87% of implanted eyes gained ≥ 1 line of CDVA, and 3% of patients (n = 1) lost one line of CDVA; 55% of eyes attained a manifest refraction spherical equivalent between +1.50 and -1.50 D. Epithelial remodeling was greater at the wider and thicker end (+11.33 µm ± 12.95; p < 0.001 relative to the initial value) than at the narrower and thinner end (+2.24 µm ± 5.67; p = 0.01). Coma aberration was significantly reduced from 1.62 ± 0.81 µm to 0.99 ± 0.59 µm (p < 0.001). Conclusions: AJL-PRO + ICRS implantation for duck-type keratoconus improves refractive, topographic, aberrometric and visual parameters and induces progressive epithelial thickening along the segment.

Intraocular Lens Calcification After Pseudophakic Endothelial Keratoplasty.

PURPOSE: To determine the incidence and to document risk factors for intraocular lens (IOL) calcification after pseudophakic endothelial keratoplasty. METHODS: We retrospectively studied 2700 consecutive penetrating, anterior lamellar and endothelial keratoplasties carried out between December 1992 and June 2022 at the National Eye Hospital, Paris, France. DESIGN: Retrospective cohort study. RESULTS: All IOL calcification cases were associated with endothelial keratoplasty. Out of 588 endothelial keratoplasty procedures, 576 eyes were pseudophakic at the end of surgery. Fourteen cases of IOL calcification were observed during follow-up. The cumulative incidence of IOL calcification after endothelial keratoplasty was 4.5%±1.3% at 60 months. Hydrophilic acrylic IOL material (P < .001) and use of SF6 for anterior chamber tamponade (P = .001) were significantly and independently associated with the cumulative incidence of IOL calcification. CONCLUSION: The incidence of IOL calcifications seems to be around 5%. Ophthalmologists should avoid hydrophilic acrylic IOLs in patients with endothelial disorders. When the patient already has a hydrophilic IOL, SF6 should be avoided. The only effective treatment is IOL exchange.

Corneal Epithelial Thickness Mapping in the Diagnosis of Ocular Surface Disorders Involving the Corneal Epithelium: A Comparative Study.

PURPOSE: The purpose of this study was to analyze the role of corneal epithelial thickness (ET) mapping provided by spectral domain optical coherence tomography in the diagnosis of ocular surface disorders (OSDs) involving the corneal epithelium. DESIGN: This was a retrospective comparative study. METHODS: Institutional settings are as follows. Study population includes 303 eyes with an OSD and 55 normal eyes (controls). Observation procedures include spectral domain optical coherence tomography with epithelial mapping in the central 6 mm. Main outcome measures include ET map classification (normal, doughnut, spoke-wheel, localized/diffuse, and thinning/thickening patterns) and ET data and statistics (minimum, maximum, and SD). A quantitative threshold was determined with receiver operating curves to distinguish pathological from normal corneas. Sensitivity and specificity of classification and quantitative data were calculated using all eyes to assess the ability to distinguish corneas with a given corneal disorder from other conditions. RESULTS: Classification of full agreement between 3 readers was obtained in 75.4% to 99.4% of cases. Main OSD features were keratoconus (135 eyes), doughnut pattern (sensitivity/specificity = 56/94%), and max-min ET ≥ 13 µm (84/43%); limbal deficiency (56 eyes), spoke-wheel pattern (66/98%), and max-min ET ≥ 14 µm (91/59%); epithelial basement membrane dystrophy (55 eyes), inferior thickening pattern (55/92%), and central ET > 56 µm (53/81%); dry eye (21 eyes), superior thinning pattern (67/88%), and minimal ET ≤ 44 µm (86/48%); pterygium (10 eyes), nasal thickening pattern (100/86%), and nasal ET > 56 µm (80/71%); and in situ carcinoma (11 eyes), max ET > 60 µm (91/60%), and ET SD >5 µm (100/58%). CONCLUSIONS: The epithelial map pattern recognition combined with quantitative analysis of ET is relevant for the diagnosis of OSDs and for distinguishing various OSDs from each other. Deep learning analysis of big data could lead to the fully automated diagnosis of these disorders.

Anterior chamber fibrin reaction during Descemet membrane endothelial keratoplasty.

PURPOSE: To report a series of five cases of intraoperative spontaneous anterior chamber fibrin reaction during Descemet Membrane Endothelial Keratoplasty (DMEK). METHODS: We retrospectively collected demographic data and data for ocular disease history for each patient. Donor age, preoperative graft endothelial density, surgical complications on surgery and intraoperative OCT videos, intraoperative management and outcome were assessed. The same standardized DMEK technique was used for all patients. RESULTS: We report intraoperative fibrin formation in five eyes subjected to DMEK. Three pseudophakic eyes underwent single DMEK, and the other two underwent combined DMEK and cataract surgery. In one case, a fibrin filament was observed before graft insertion, with multiplication during surgery, whereas, in the other four cases, strands of fibrin from the iris appeared after graft insertion. This complication resulted in graft failure in four cases (80%). No recipient- or donor-related risk factor was identified. CONCLUSIONS AND IMPORTANCE: The anterior chamber fibrin reaction is a very uncommon complication of DMEK. The underlying pathophysiological mechanisms remain unknown, but analyses of surgical videos and intraoperative OCT suggest iris involvement. This phenomenon may be induced by chronic subclinical anterior chamber inflammation, due to a blood-aqueous barrier breakdown associated with acute iris trauma during surgery. Thus, intraoperative microtraumatism of the iris should be avoided.

Tocilizumab versus Rituximab in Patients with Moderate to Severe Steroid-resistant Graves' Orbitopathy.

INTRODUCTION: To describe the efficacy of tocilizumab in patients with Graves' orbitopathy resistant or dependent to steroids and compare to rituximab treated patients. PATIENTS AND METHODS: Graves's orbitopathy response was considered as decrease of at least 2 points of the CAS. RESULTS: Twenty-one patients were included, 7 patients were treated with tocilizumab and 14 with rituximab. The primary was achieved in all 7 patients (100%) on tocilizumab and 9 out of 14 patients on (64%) rituximab (p = .17). Mean change in CAS was consistent with a decrease of 3.3 ± 0.5 points in patients on tocilizumab versus 2.5 ± 1.9 in patients on rituximab (p = .07). One patient on tocilizumab (14%) and 4 patients (29%) on rituximab experienced significant relapse during the follow-up. The difference in relapse-free survival was not significant in patients on tocilizumab (10.8 ± 4 months) compared with rituximab (17.88 ± 3.66). CONCLUSION: We showed a significant improvement in the CAS, visual acuity, diplopia, and proptosis with both tocilizumab and rituximab.

Anterior chamber tap cytology in acute postoperative endophthalmitis: a case-control study.

AIMS: To determine anterior chamber tap cytology characteristics in acute postoperative bacterial endophthalmitis. METHODS: 488 eyes of 488 patients were included in this retrospective case-control study. The study group included 93 eyes with bacteriologically documented endophthalmitis and 85 eyes with clinical endophthalmitis. The control group included 33 eyes with non-infectious postoperative inflammation, 116 eyes with acute uveitis and 161 cataract surgery eyes with no ocular inflammation. Cytological analysis, direct examination and microbiological cultures were performed in aqueous humour (AqH) samples. Inclusion criteria for the study group were the following: suspected endophthalmitis within 30 days following cataract surgery by phacoemulsification, secondary lens implantation, pars plana vitrectomy or intravitreal injection; best-corrected visual acuity (BCVA) <20/400; hypopyon or cyclitic membrane; absence of visibility of the retina; vitritis at a slit-lamp examination or in ultrasound B-scan. RESULTS: Cell line counts (mainly polymorphonuclear neutrophils) were significantly higher in the two endophthalmitis study subgroups than in the three control subgroups. The study group showed a predominance of polymorphonuclear neutrophils as opposed to the three control subgroups including uveitis (p<0.00001). The best sensitivity/specificity was obtained using a polymorphonuclear neutrophil threshold of 10 per field (sensitivity, 0.90; specificity, 0.75). The sensitivity of the bacterial culture was 32% in the AqH. High neutrophil count was associated with poorer initial BCVA (rs=0.62; p<0.00001) and higher risk of retinal detachment during (p=0.04) and after (p<0.001) hospitalisation. CONCLUSION: Anterior chamber tap cytology is a quick and accessible tool complementary to culture and PCR for the management of acute postoperative endophthalmitis.

Freeze-Dried Versus Cryopreserved Amniotic Membranes in Corneal Ulcers Treated by Overlay Transplantation: A Case-Control Study.

PURPOSE: The purpose of this study was to assess cryopreserved amniotic membrane (C-AM) versus chorion-free freeze-dried amniotic membrane (FD-AM) overlay transplantation for corneal ulcers in a French tertiary ophthalmology hospital. METHODS: Between March and July 2020, when C-AMs were not available because of the COVID-19 pandemic, 28 corneal ulcers underwent FD-AM overlay transplantation and were retrospectively compared with 22 corneal ulcers treated with C-AM during the same period in 2018. All patients had at least 3 months of follow-up, and those who underwent combined surgeries were excluded. Ulcers were assessed at baseline and then at 72 hours, 1 month, and 3 months. Population demographics, follow-up time, ulcer etiologies, epithelial defect size, ulcer depth, and complications were also recorded. RESULTS: Baseline characteristics and clinical features of both groups were comparable. There was no statistically significant difference in the number of overlay AM transplantations (P = 0.52) or early detachments (P = 0.57). At 3 months, the corneal healing rate was almost the same in both groups (89% and 91% for FD-AM and C-AM, respectively; P = 0.87). Complications were equally uncommon (11% and 9%, respectively; P = 0.92). In logistic regression, the type of the membrane did not influence corneal healing at 1 month (P = 0.42) or 3 months (P = 0.99), regardless of the depth of the ulcer. However, whatever the type of AM used, the deeper the ulcer was, the less likely it was to heal at 3 months (P = 0.02). CONCLUSIONS: This is the first study that provides positive insight into the effectiveness of FD-AM compared with C-AM when used as overlay transplantation for treating corneal ulcers.

Update on fungal keratitis in France: a case-control study.

PURPOSE: To report an epidemiological update of documented fungal keratitis (FK) in a French tertiary ophthalmological centre from 2014 to 2018 in comparison with a previous period from 1993 to 2008. METHODS: Sixty-two consecutive FK documented by microbiological corneal scrapings were compared with the 64 FK of the previous study. Amphotericin B and voriconazole eye drops were administered hourly. Population characteristics, clinical findings, aetiological organisms and treatments were analysed. RESULTS: The most frequently identified fungi were Fusarium (61%), Aspergillus (6.5%) and Candida (5%). Thirty out of 44 cases examined with in vivo confocal microscopy (IVCM) presented filaments. Ten required conventional cross-linking, 9 therapeutic penetrating keratoplasty, and 2 enucleation. Risk factors significantly associated with the absence of response to medical treatment were patient age (p = 0.01), presence of a deep stromal infiltrate at presentation (p = 0.04) and high numbers of filaments in IVCM images (p = 0.01). The two populations were comparable in age, but not in sex ratio males/females (18/44 versus 37/26 in the previous study; p = 0.001). The frequency of contact lens-associated infection increased from 35.5% to 71% (p = 0.0001) between the two periods. Since then, filamentous FK increased from 69% (44/64) to 95% (59/62) (p = 0.0001). A history of keratoplasty was less frequently reported during the last period (3.2% (2/62) versus 17% (11/64) of cases (p = 0.01)). A clear decrease in the frequency of therapeutic keratoplasty was noted from 39% (25/64) to 14% (9/62) (p = 0.02). CONCLUSION: The frequency of filamentous keratomycosis is currently increasing. Elderly patients and the presence of numerous filaments in IVCM are associated with poor clinical outcomes.

Early corneal pachymetry maps after cataract surgery and influence of 3D digital visualization system in minimizing corneal oedema.

PURPOSE: To describe the early topography of corneal swelling occurring after cataract surgery and to evaluate the impact of the three-dimensional (3D) digital visualization system in minimizing corneal oedema. METHODS: Prospective observational, single-centre, consecutive case series of 134 patients undergoing cataract surgery performed by the same surgeon, with either 3D or conventional visualization systems. Eyes were assigned to two groups based on their anterior chamber depth (group ACD ≤3 mm and group ACD >3 mm). Optical coherence tomography was performed to evaluate postoperative corneal swelling. RESULTS: Three corneal swelling profiles were identified on the first postoperative day type 1, limited corneal oedema near peripheral corneal incisions; type 2, dome-shaped corneal swelling spreading from the principal corneal incision and reaching the paracentral cornea; type 3, continuous oedema spreading from the principal incision to central cornea, with a generalized oedema predominating in the upper part of the cornea. On the first day after surgery, in group ACD ≤3 mm, visual acuity was significantly better in patients undergoing surgery with 3D visualization (0.023 vs 0.072 logMar, p = 0.014) with reduced central corneal thickening 17.3 µm (±3.2) in comparison with conventional visualization 44.0 µm (±9.3) (p = 0.0082). In group ACD >3 mm, no significant association was found between the use of the 3D system and pachymetry changes and early visual rehabilitation. On day 21 after surgery, no significant differences in corneal pachymetry values were observed between the two surgical approaches in both groups. CONCLUSIONS: We describe early postoperative corneal map profiles providing insight into the pathogenesis of postoperative corneal swelling and possible prevention strategies. By improving visualization of the narrow surgical space in patients with shallow anterior chambers, the 3D system could help to minimize postoperative corneal oedema.

Corneal and Epithelial Thickness Mapping: Comparison of Swept-Source- and Spectral-Domain-Optical Coherence Tomography.

OBJECTIVE: To compare the results and repeatability of the corneal thickness (CT) and epithelial thickness (ET) maps provided by Swept-Source-Optical Coherence Tomography with those of Spectral-Domain-OCT in normal eyes. METHODS: 30 normal eyes of 30 patients were assessed by 3 trained operators with SS-OCT and SD-OCT. RESULTS: The central and minimum ET obtained with both devices were correlated: central ET, r = 0.86, p < 0.05; minimum ET, r = 0.72, p < 0.05. Compared with SD-OCT, SS-OCT tended to underestimate these figures by 1.4 and 1.9 µm on average. The central and minimum CT obtained with both devices were strongly correlated: central CT, r = 0.994, p < 0.05; minimum CT, r = 0.995, p < 0.05. SS-OCT tended to overestimate these figures by 11 and 14 µm on average. Repeatability was good for both devices with a mean coefficient of variation of measurements <6% for ET and <2% for CT. Interoperator variability (standard deviation and COV) was significantly higher for SS-OCT than for SD-OCT for all local epithelial thicknesses and significantly lower for the central CT and several local corneal thicknesses, whereas no significant differences between both technologies were found for the central and minimum ET and the minimum CT. CONCLUSION: SS-OCT and SD-OCT provide reproducible measurements of CT and ET in normal corneas with a strong correlation between both technologies. However, both technologies are not interchangeable when the main thickness parameters (i.e., central and minimum CT and minimum ET) are used for diagnosing early keratoconus or calculating the expected residual stromal bed thickness before corneal refractive surgery or anterior lamellar keratoplasty.

Comparative Study of Asymmetric Versus Non-asymmetric Intrastromal Corneal Ring Segments for the Management of Keratoconus.

PURPOSE: To compare the outcomes obtained with models of asymmetric and non-asymmetric intracorneal ring segments (ICRS) in keratoconic eyes with asymmetric topo-graphic patterns. METHODS: In this prospective observational study, ICRS were implanted alternately in patients with the same tomographic patterns of keratoconus assigned to four groups. Patients with the "duck" phenotype received one asymmetric or non-asymmetric ICRS and patients with the "snowman" pheno-type received two asymmetric or non-asymmetric ICRS. Visual, refractive, astigmatism, keratometric, and corneal aberrometry changes were evaluated over a 6-month follow-up period. RESULTS: Sixty-eight eyes were analyzed. No significant difference was observed between the use of one asymmetric and one non-asymmetric ICRS in duck phenotypes. In snowman keratoconus, the inferior-superior index decreased significantly (P = .03) with asymmetric but not with non-asymmetric ICRS implantation. Total corneal higher order aberrations and coma rates were lower, but not significantly so, after the implantation of two asymmetric ICRS in snowman phenotypes (2.85 ± 0.89 to 2.60 ± 0.91 µm, P = .20 and 2.64 ± 0.93 to 2.39 ± 0.98 µm, P = .21), and significantly higher after the implantation of two non-asymmetric ICRS (2.56 ± 1.28 to 3.08 ± 1.62 µm, P = .02 and 2.34 ± 1.27 to 2.84 ± 1.62 µm, P = .02). CONCLUSIONS: Asymmetric ICRS did not improve the outcomes of ICRS implantation in duck keratoconus. However, the implantation of two asymmetric ICRS was more effective than that of two non-asymmetric ICRS for decreasing vertical asymmetry and preventing increases in corneal aberration in the snowman phenotype of keratoconus. [J Refract Surg. 2021;37(8):552-561.].

Postoperative Corneal Epithelial Remodeling After Intracorneal Ring Segment Procedures for Keratoconus: An Optical Coherence Tomography Study.

PURPOSE: To assess epithelial corneal remodeling by anterior segment optical coherence tomography (AS-OCT) after intracorneal ring segments (ICRS) implantation in keratoconic eyes. METHODS: This prospective observational study included patients with keratoconus receiving ICRS of different arc lengths according to their tomographic pattern. AS-OCT and corneal topography (Scheimpflug camera) were performed before and 1, 3, and 6 months after surgery. Corneal pachymetry mapping was performed and total corneal and epithelial thicknesses (3-mm central and 16 points on 6-mm zone) were measured over the pupil center using AS-OCT. Topographic parameters were also assessed. RESULTS: A total of 68 keratoconic eyes were analyzed (Amsler-Krumeich stages 1 to 4) in four groups of 17 eyes: 210° ICRS, 320° ICRS, double 160° ICRS, and single 160° ICRS. Corneal pachymetry mapping revealed that epithelial thickness increased significantly in the internal zones juxtaposed to the ICRS without smoothing during the postoperative period (P < .05). Mean maximum epithelial thickness increased from 67 ± 6 to 79 ± 7 µm for 210° ICRS, 66 ± 9 to 82 ± 4 µm for 320° ICRS, 63 ± 6 to 78 ± 7 µm for double 160° ICRS, and 62 ± 5 to 77 ± 5 µm for single 160° ICRS (P < .0001). Significant epithelial thickening at the apex of the cone was observed in all groups (P < .05). CONCLUSIONS: Significant epithelial thickening occurs after ICRS implantation adjacent to the ICRS to compensate for the ridge created with a thickening of epithelium over the cone due to regularization of the stromal surface. [J Refract Surg. 2021;37(6):404-413.].

Long-Term Results and Refractive Error After Cataract Surgery With a Scleral Incision in Eyes With Deep Anterior Lamellar Keratoplasty.

PURPOSE: Phacoemulsification in eyes with deep anterior lamellar keratoplasty (DALK) is associated with possible decreased graft survival and difficult IOL power calculation. We assessed cataract surgery in eyes with previous DALK. METHODS: Thirty-three consecutive eyes with DALK and further phacoemulsification with scleral incision were included in this retrospective study. At each postoperative visit, eyes were assessed with manifest refraction, optical coherence tomography, specular corneal topography, and noncontact wide-field specular microscopy. RESULTS: The average postkeratoplasty follow-up time was 102 months [95%-CI, (85-119)]. Cataract surgery was performed on average 43 months (30-56) after DALK. The average postphacoemulsification follow-up time was 58 months [42-74]. All grafts remained clear during follow-up. The best spectacle-corrected logarithm of the minimum angle of resolution visual acuity improved by 2.5 lines [1.8-3.1] on average after cataract surgery from 0.58 (20/77) to 0.34 (20/44) (P < 0.001). The spherical equivalent and intraocular pressure significantly improved from -4.1 D to -1.7 D and from 15.9 to 14.0 mm Hg, respectively. The corneal central thickness was not significantly modified, and the endothelial density decreased by 5.3% from 2081 to 1970 cells/mm2 (P = 0.003). The minimal difference between the achieved and predicted spherical equivalents [-0.05 D, (-2.33; +2.21)] was obtained with the Hoffer Q formula using the IOLMaster axial length and the Orbscan keratometry. CONCLUSIONS: Patients with DALK who underwent phacoemulsification with a scleral incision had a satisfying residual refractive error, very high graft survival, and very few complications. The Hoffer Q formula with the IOLMaster axial length and the specular corneal topography keratometry seems to be the most accurate for IOL calculation.

Prevention of infection after corneal refractive surgery: a French survey.

PURPOSE: To report the French refractive surgeons' real-life practices for preventing infection after corneal refractive surgery (photorefractive keratotomy [PRK], laser in situ keratomileusis [LASIK], and small-incision lenticule extraction). SETTING: France. DESIGN: Anonymous practice survey. METHODS: The questionnaire was sent in a single email invitation to 400 declared refractive surgeons. The following information was recorded between December 2019 and April 2020, before the coronavirus pandemic: demographics data, preoperative evaluation and preparation of the patient, surgical management, immediate and postoperative protocol, and infections reported after corneal refractive surgery. RESULTS: Eighty-three of 400 surgeons (20.75%) responded to the questionnaire; 55 (66.0%) performed more than 50 corneal refractive surgeries a year, and 25 (30.1%) performed more than 200 procedures a year. Thirty-six (43.4%) surgeons wore 3 protective items, 37 (44.6%) 2, 5 (6.0%) 1, and 5 (6.0%) zero. Seventy-seven (92.8%) surgeons used povidone-iodine for skin area disinfection and 54 (65%) for conjunctival fornix disinfection. The contact time of povidone-iodine was less than 3 minutes for 71 (85.0%) surgeons. Twenty surgeons (24.1%) reported at least 1 postrefractive surgery infection. Twenty percent of surgeons who wore sterile gloves for PRK reported postoperative infections compared with 62.5% for those who did not (P = .008). These figures were, respectively, 8.7% and 66.7% for the use of sterile gloves during LASIK (P = .002); 8.9% of surgeons who wore surgical masks for LASIK reported postoperative infections compared with 50.0% for those who did not (P = .01). CONCLUSIONS: Practices are variable among French refractive surgeons. Wearing a surgical mask and sterile gloves during corneal refractive surgery appears to be advisable.

Multimodal imaging of Hurler syndrome-related keratopathy treated with deep anterior lamellar keratoplasty.

BACKGROUND: Hurler syndrome-associated keratopathy is an exceedingly rare corneal disorder that requires corneal transplantation in advanced stages. Precise assessment of the corneal condition is necessary for deciding which type of keratoplasty (i.e., deep anterior lamellar or penetrating) should be proposed. We aimed to confront the results of multimodal imaging with those of histology in a case of Hurler syndrome-associated keratopathy. CASE PRESENTATION: A 16-year-old patient with Hurler's syndrome treated with hematopoietic stem cell transplantation was referred for decreased vision related to advanced keratopathy. The patient was treated with deep anterior lamellar keratoplasty (DALK) in both eyes with uncomplicated outcome. Visual acuity improved from 0.1 (20/200) preoperatively to 0.32 (20/63) and 0.63 (20/32) after transplantation. The corneal endothelial cell density was 2400 cells/mm2 in both eyes 3 years after transplantation. In vivo confocal microscopy (IVCM) and spectral domain optical coherence tomography (SD-OCT) were performed preoperatively. The corneal buttons retrieved during keratoplasty were processed for histology. In SD-OCT scans, corneal opacities appeared as diffuse stromal hyperreflectivity associated with increased corneal thickness. IVCM showed diffuse cytoplasmic granular hyperreflectivity and rounded/ellipsoid aspects of keratocytes, presence of small intracellular vacuoles, and hyperreflective epithelial intercellular spaces. Bowman's layer was thin and irregular. The corneal endothelium was poorly visualized but no endothelial damage was observed. Histology showed irregular orientation and organization of stromal lamellae, with the presence of macrophages whose cytoplasm appeared clear and granular. A perinuclear clear halo was visible within the epithelial basal cells. Bowman's layer featured breaks and irregularities. CONCLUSIONS: The observed corneal multimodal imaging features in mucopolysaccharidosis-related keratopathy were concordant with histology. Compared with standard histology, multimodal imaging allowed additional keratocyte features to be observed. It revealed both morphological and structural changes of all corneal layers but the endothelium. This information is essential for therapeutic management which should include DALK as the first-choice treatment in case of impaired visual acuity.