Cornea最新文献

Purpose: The purpose of this study was to investigate the differences in guttae ultramorphology and their relation to visual function in eyes with Fuchs endothelial corneal dystrophy (FECD).

Methods: Thirty FECD eyes without ocular comorbidities were included. Visual functional parameters (best-corrected visual acuity with high-contrast and low-contrast letters and contrast sensitivity/LogCS) and corneal morphology measured with Scheimpflug tomography (Pentacam) were assessed. The surgically removed Descemet membranes were examined by light and transmission electron microscopy.

Results: Preoperative mean best-corrected visual acuity (logarithm of the minimum angle of resolution) was 0.52 ± 0.18, LogCS 0.96 ± 0.21 and central corneal thickness 640 ± 55 μm. All eyes had signs of subclinical corneal edema in Scheimpflug tomography; clinically visible corneal edema was present in 40% of eyes. Histological findings included a posterior fibrillar zone (PFZ) in 10 specimens (33%) and abnormal collagen depositions in Descemet membranes in 14 specimens (47%). Guttae buried within the PFZ were present only in eyes with clinically visible edema (n = 4, 13%). There was no difference in visual function results and tomography parameters between eyes with and without PFZ or between protruding guttae and guttae embedded in a PFZ, respectively.

Conclusions: Guttae morphology and density were not correlated with visual functional parameters. Guttae buried in a PFZ occurred only in eyes with clinically manifest edema, and thereby, they are an ultramorphological sign for advanced FECD. Subclinical edema was present in all eyes and might be more relevant for quality of vision than guttae ultramorphology.

Purpose: To describe the use of crescentic autograft as a graft salvage technique for inadvertently undersized donor lenticules in superficial anterior lamellar keratoplasty (SALK).

Methods: A prospective interventional study included 5 eyes of 4 patients who underwent SALK and had an inadvertently undersized donor lenticule. The described technique involves the preparation of a crescent-shaped graft from the host lenticule itself that is matched to fit into the remaining bare recipient stromal bed.

Results: At 6-week follow-up, the crescentic autograft was uniformly epithelized along with the donor tissue. There were no incidences of graft dehiscence, rejection, or infection.

Conclusions: Crescentic autograft from the host lenticule offers a simple, easy-to perform, and unique technique to manage cases of undersized donor lenticules in SALK with no additional risks.

Purpose: The aim of this study was to assess the outcomes of off-centered Descemet membrane endothelial keratoplasty (DMEK) grafts compared to descemetorhexis.

Methods: This is a retrospective case series of DMEK procedures conducted between June 2022 and July 2023 with postoperative graft decentration, characterized by a gap between the graft and descemetorhexis edge.

Results: Eight eyes of 8 patients met the inclusion criteria. The average gap between the descemetorhexis edge and DMEK graft was 911.2 μm (range 306-1468). The resulting focal peripheral edema overlying the gap resolved in all cases, with a median time of 3 months. Best-corrected visual acuity improved from 0.49 (±0.26) logarithm of the minimum angle of resolution to 0.01 (±0.02) logarithm of the minimum angle of resolution at 12 months (P = 0.003). Central corneal thickness decreased from 646.5 (±177.8) μm to 473.7 (±29.6) μm at 12 months (P = 0.05). One eye, in the overlapped area of host-donor Descemet membranes, had small peripheral partial graft detachment less than one-third of graft surface area. No eyes required graft rebubbling. A larger descemetorhexis to DMEK gap showed a trend toward longer resolution times (P = 0.06). Focal edema in the inferonasal periphery took longer to recover compared with the nasal position (P = 0.01). Larger descemetorhexis to DMEK gaps did not significantly influence the longitudinal visual acuity trend (P = 0.75).

Conclusions: Decentered DMEK, characterized by a gap between the graft and descemetorhexis edge, leads to focal stromal edema that diminishes over time, with no impact on final visual acuity.

Purpose: To evaluate the outcomes of patients treated with corneal allogeneic intrastromal ring segments cut with femtosecond laser (Femto-CAIRS) without concomitant corneal crosslinking.

Methods: Patients with keratoconus treated with Femto-CAIRS at the American University of Beirut Medical Center were included (May 2022-January 2023). A proprietary software program was developed on the femtosecond laser to cut allogeneic segments. Visual, refractive, tomographic, aberrometric, and epithelial data by anterior segment optical coherence tomography were measured at baseline and 1, 3, 6, and 12 months postoperatively.

Results: 20 eyes of 15 patients were included and followed up for 12 months. The manifest refraction spherical equivalent and cylinder improved from -6.79 ± 4.9 diopter (D) and -4.25 ± 1.8 D to -1.88 ± 2.9 D (P < 0.001) and -2.64 ± 1.4 D (P = 0.01) 12 months postoperatively, respectively. 75% of eyes gained 3 or more corrected distance visual acuity lines, most of which (65%) gained 4 lines or more 12 months postoperatively. The maximum keratometry and vertical coma decreased by 5.2 D (P < 0.001) and 1 μm (P = 0.001), respectively, 3 months postoperatively and remained stable until 12 months. The largest anterior stromal elevation over the central 5-mm diameter decreased from 36.0 ± 18.2 μm preoperatively to 19.9 ± 9.25 μm at 1 week postoperatively (P < 0.001) and remained relatively stable. Epithelial thickness over the cone increased relative to baseline starting 1 month postoperatively and becoming stable after 6 months while the mean epithelial thickness central to the ring peaked at 1 month after which it decreased to reach a plateau at 6 months.

Conclusions: The Femto-CAIRS procedure improves visual and tomographic parameters and allows repeatable and safe results with the possibility of customization for individualized management.

Purpose: The novel endothelial keratoprosthesis EndoArt improves corneal edema by reducing the inflow of aqueous humor into the cornea. We assessed the early outcome after EndoArt implantation in patients at a high risk of graft failure after keratoplasty.

Methods: This retrospective study included 14 patients with high-risk eyes owing to at least one of the following risk factors for graft failure after keratoplasty: multiple previous surgeries (glaucoma surgery, keratoplasty) and recurrent intraocular inflammation because of uveitis, aniridia, or anterior synechia. After descemetorhexis, the EndoArt keratoprosthesis was placed on the posterior stroma, secured with a gas bubble and 1 to 3 transcorneal holding sutures. Best spectacle-corrected visual acuity and central corneal thickness were calculated preoperatively and postoperatively. In addition, detachment of the keratoprosthesis and the need for additional gas injections (rebubbling) were analyzed.

Results: Octafluoropropane (C3F8) 12% in 11 patients and sulfur hexafluoride 20% in 3 patients were used to attach EndoArt. Detachments requiring at least 1 rebubbling occurred in 8 eyes. Preoperative best spectacle-corrected visual acuity was 1.6 (±0.6) logarithm of the minimal angle of resolution and improved to 1.3 (±0.6) after 12 weeks. Preoperative central corneal thickness (771.8 μm ± 157) significantly decreased postoperatively in all patients (622.1 μm ± 184.7 [P = 0.025] and 562.8 μm ± 183.6 [P = 0.012] after 6 and 12 weeks, respectively).

Conclusions: EndoArt improved visual acuity and significantly reduced corneal thickness within 3 months postoperatively, subjectively, but not statistically significantly. The rebubbling rates in this cohort with an altered anterior segment anatomy were relatively high. Patients at a high risk of graft failure may benefit from this novel endothelial keratoprosthesis.

Purpose: To examine clinical results up to 10 years after Descemet Membrane Endothelial Keratoplasty (DMEK) and Triple-DMEK.

Methods: Prospective study including 201 eyes, of which 54 eyes [38 DMEKs and 16 Triple-DMEKs; Fuchs endothelial dystrophy (n = 45), pseudophakic bullous keratopathy (n = 9)] reached the minimum follow-up of 5 years and were followed up for up to 10 years. We evaluated best-corrected visual acuity (BCVA, logarithm of the minimum angle of resolution [logMAR]), endothelial cell density (ECD, cells/mm2), minimal central corneal thickness (CCT, μm), central retinal thickness (μm), rebubbling, graft survival and re-DMEK rate, chamber angle alterations, and incidence of glaucoma.

Results: Fifty-four eyes had a 5-year and 37 eyes an 8- to 10-year follow-up. Mean follow-up was 94.4 ± 12.1 months. Best-corrected visual acuity increased from 0.6 ± 0.3 logMAR to 0.1 ± 0.2 logMAR at 6 months (P ≤ 0.001) and was 539 ± 54 μm at long term. Endothelial cell density decreased from 2488 ± 320.9 (donor) to 980.1 ± 437 cells/mm2 with an average ECD loss/year of 4% and did not correlate with BCVA. Central corneal thickness decreased from 596.9 ± 82.2 μm to 498.6 ± 24.3 μm at 12 months (P ≤ 0.001) and remained stable (P = 1.000). Mean rebubbling rate was 0.3 ± 0.5/eye and did not correlate with BCVA. Eight eyes (14.8%) received at least 1 rebubbling. Primary graft failure/rejection rate was 1.5%/0% within the first postoperative year, and secondary graft failure rate was 12.4% at 7 years. Eight eyes (preoperative n = 3, de novo n = 5) had open-angle glaucoma without chamber angle changes (14.8%, P ≤ 0.001).

Conclusions: Although ECD decreases continuously in the long-term follow-up, excellent visual acuity can be preserved 10 years after DMEK and Triple-DMEK. The final outcome can be estimated 6 months after surgery.

Purpose: To manage ocular surface complications and recover conjunctival and corneal epithelia after unilateral severe chemical burn.

Methods: We performed simple conjunctival epithelial transplantation (SCET) to obtain renewal of fornix and bulbar-tarsal conjunctiva epithelium, followed by simple limbal epithelial transplantation (SLET) to recover limbal function and epithelial corneal surface. Slit-lamp examination, fluorescein staining, in vivo confocal microscopy, Kheirkhah grading system for symblepharon severity, Wong-Baker FACES Pain Rating Scale, and best-corrected visual acuity were assessed before surgery, at 1 to 3 months after SCET and SLET, and thereafter at 6 to 12 to 36 months.

Results: Two patients with unilateral burn injuries underwent surgery. Eye mobility and fornix reconstruction were promptly achieved, and conjunctival epithelium with goblet cells was observed on the bulbar and tarsal conjunctiva 3 months after SCET. After SLET, corneal epithelium and cornea-conjunctiva transition zone were observed at 3 and 6 months, respectively. From before surgery to 6 months after SLET, symblepharon improved from grade IVa2 and IIIb2 to Ic0 and Ib0, the Wong-Baker FACES Pain Rating Scale changed from grade 6 and 4 to 0, and best-corrected visual acuity upgraded from 1.40 and 1.10 logarithm of the minimum angle of resolution to 0.5 logarithm of the minimum angle of resolution, in patient 1 and 2, respectively. After 3 years, results remained stable.

Conclusions: SCET effectively healed the bare conjunctival area relieving subjective symptoms and discomfort. Sequential SCET and SLET showed to be feasible in restoring a normal ocular surface with long-lasting results suggesting the aim in patients with severe ocular burn is not merely corneal epithelium renewal but also the regeneration of ocular surface homeostasis.

Purpose: This study sought to determine the effect of donor preservation time and other donor tissue factors on the clinical outcomes of keratolimbal allograft (KLAL) transplantation.

Methods: In this retrospective chart review of patients who underwent KLAL transplantation, electronic health records were reviewed for relevant patient ocular and surgical history. Donor tissue factors were collected from donor reports. The primary outcome measure was time to epithelialization. Exclusion criteria included prior ocular surface stem cell transplantation, loss to follow-up, missing data from medical records, indication for surgery other than limbal stem cell deficiency, and early removal of KLAL tissue. Regression analysis was performed to compare time to epithelialization and donor tissue factors. Subgroup analysis was performed using the Student t test to evaluate the impact of donor preservation time on time to epithelialization.

Results: A total of 154 eyes were identified of which 122 were included for analysis. The mean time to epithelialization was 55 days and median was 35 days. No donor tissue factors were found to affect total time to corneal epithelialization. Subgroup analysis comparing the effect of different total preservation times on time to epithelialization did not reveal any statistically significant associations.

Conclusions: No relationship was found between time to donor tissue preservation and time to epithelialization after KLAL surgery. It appears that limbal stem cells can be safely stored for up to 9 days in corneal storage solution in hypothermic temperatures without clinical consequences.