Cornea最新文献

Purpose: Boston keratoprosthesis (KPro) is a widely used treatment for corneal diseases unsuitable for traditional keratoplasty. Postoperative complications, notably retroprosthetic membrane (RPM) formation and secondary glaucoma, significantly affect patient outcomes. Anterior segment optical coherence tomography (AS-OCT) enables precise visualization of KPro-related complications, such as angle closure and RPM formation. This study aimed to investigate the association between RPM formation and de novo angle closure in eyes with Boston KPro.

Methods: A retrospective analysis of patients who underwent Boston KPro type 1 implantation was conducted. Patients with preoperative angles documented by AS-OCT and a minimum 1-year follow-up with serial AS-OCT imaging were included. Demographic data, surgical details, visual acuity, intraocular pressure, and complications were recorded. The presence of RPM and angle closure was assessed clinically and via AS-OCT.

Results: This study included 18 eyes from 18 patients who underwent KPro implantation with a follow-up period averaging 4.7 years. Preoperative visual acuity was poor (20/400 or worse) in all eyes, with an improvement in 78% of cases to 20/200 or better postoperatively. Complications included angle closure in 61% of eyes, with a significant association between retroprosthetic membrane (RPM) formation and angle closure ( P = 0.0012). De novo glaucoma developed in 4 eyes, primarily associated with RPM and angle closure, and was managed medically.

Conclusions: This study highlights a significant association between RPM formation and de novo angle closure in eyes with Boston KPro. Our study findings strongly suggest that RPM formation plays a role in inducing angle closure, contributing to glaucoma development, and is the first study to provide AS-OCT evidence of potential causality. Understanding these associations can improve patient care and outcomes after KPro implantation. Strategies aimed at reducing RPM formation could potentially mitigate other KPro-related complications, including angle closure and de novo glaucoma.

Purpose: To describe the surgical technique for 2-piece mushroom penetrating keratoplasty using the "pull-through" technique in infant eyes.

Methods: Using a 250-μm microkeratome head, the donor cornea was split into anterior and posterior lamella, which were then punched to 8.0 to 8.5 and 6.0 mm, respectively. After partial trephination of the host cornea (depth = 250 μm, diameter = 7.5-8.0 mm), anterior stromal keratectomy was performed. Another partial-thickness trephination (6.0-mm diameter) was performed on the residual bed, which was then opened full thickness for about 1 o'clock hour at 12, 3, 6 and 9 o'clock positions. The donor anterior lamella was fixated with 4 cardinal sutures over the host residual bed that had been partially opened. Using corneal scissors, the central 6.0-mm trephination of the residual host cornea was completed full thickness and removed under the sutured donor anterior lamella. Descemet stripping automated endothelial keratoplasty microforceps were then inserted under the anterior lamella to grasp and deliver the donor posterior lamella into the anterior chamber through the pull-through technique. Suturing of the anterior lamella was completed with 12 additional interrupted stitches.

Results: Surgery was performed in 7 eyes with Peters anomaly between 2 and 12 months. No intraoperative complications were recorded. All grafts were clear at the last follow-up. All patients were able to fix and follow.

Conclusions: In infant eyes, fixation of a large anterior lamella over a smaller partially excised recipient cornea allows selective exchange of the centrally diseased host cornea under "semiclosed system" conditions, overcoming the threat of expulsion of intraocular structures posed by excessive vitreous pressure and possibly minimizing donor endothelial trauma.

Purpose: The aim of this study was to perform a systematic review of diagnostic test accuracy of the criteria used to define keratoconus progression.

Methods: A systematic search of MEDLINE/PubMed, EMBASE, Web of Science Core Collection, and Cochrane Central Register of Controlled Trials (CENTRAL) databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses of Diagnostic Test Accuracy Studies (PRISMA-DTA) guidelines, from inception to December 31, 2024. The study protocol was preregistered in the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42023391880). Risk of bias was assessed with the Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS-2). Eligible references included randomized controlled trials, cohort studies, cross-sectional studies, and case-control studies assessing the diagnostic accuracy of criteria used to define keratoconus progression, calculating sensitivity, specificity, and diagnostic odds ratio.

Results: Fifteen studies (2 prospective and 13 retrospective) were included, comprising 3547 eyes from 2654 individual patients. Overall, best-performing diagnostic tests for keratoconus progression were Belin/Ambrósio Enhanced Ectasia Display (BAD-D); ABCD 1 criteria >95 confidence interval; and anterior best-fit sphere radius, with maximum mean sensitivity/specificity values of 0.82/0.98, 0.81/1.00, and 0.86/0.94, respectively. In 2 studies, maximum keratometry (Kmax) had high specificity (0.91 and 1.00), but low sensitivity (0.70 and 0.49). Image criteria were poorer discriminators: deep learning of color-coded maps showed very low specificity (below 0.60) while anterior segment optical coherence tomography lacked sensitivity (below 0.68).

Conclusions: Composite indexes combining multiple data such as BAD-D and ABCD, or global measurements of the corneal surfaces, such as best-fit sphere radius, might be ideal criteria to define disease progression, instead of single-point measurements.

Purpose: Describe aims, methods, characteristics of donors, donor corneas and recipients, and potential impact of the Diabetes Endothelial Keratoplasty Study (DEKS).

Methods: The DEKS is a randomized, clinical trial to assess graft success and endothelial cell density (ECD) 1 year after Descemet membrane endothelial keratoplasty (DMEK) using corneas from donors with versus without diabetes in a 1:2 minimization assignment. Diabetes severity in the donor is assessed by medical history, postmortem HbA1c, and donor skin advanced glycation end-products and oxidation markers. A central image analysis reading center assesses baseline donor, 1-month and 1-year postoperative ECD.

Results: The DEKS used corneas from 1154 donors for 1421 DMEK procedures on 1097 participants (324 bilateral) at 28 clinical sites. Forty-eight tissue preparations failed (3%). Mean donor age was 65 years; mean eye bank-determined screening ECD was 2709 cells/mm 2 . Ultimately, 106 (9%) of 1154 donors without diabetes history were classified as diabetic based on postmortem HbA1c ≥6.5%, and 509 (36%) of 1421 donor lenticules were classified as coming from diabetic donors. Recipients were 58% female, 96% White, and 53% phakic. Study eyes were treated for Fuchs endothelial corneal dystrophy (96%), pseudophakic corneal edema (2%), and failed endothelial keratoplasty (2%). Mean recipient age was 70 years; 21% had diabetes history and 26 (2%) had central laboratory determined HbA1c ≥6.5% without diabetes history.

Conclusions: The DEKS will increase understanding of factors related to DMEK success while determining whether diabetes and/or diabetes severity in the donor and/or recipient adversely affects graft success and endothelial cell loss.

Purpose: Maroteaux-Lamy syndrome (MPSVI) is a rare lysosomal storage disorder caused by an Arylsulfatase B ( ARSB ) deficiency, leading to dermatan sulfate and chondroitin-4-sulfate accumulation. It manifests various systemic clinical features. Enzyme Replacement Therapy with Galsulfase (Naglazyme) manages systemic symptoms, but ocular manifestations, such as corneal opacity, often require surgery. This study examines histopathological features of corneas in patients with MPSVI who underwent penetrating keratoplasty (PK).

Methods: A retrospective study of 3 patients with MPSVI included demographics, genetics, clinical history, and ophthalmological findings. Six corneas were analyzed with hematoxylin-eosin and histochemical stains, focusing on structural changes and glycosaminoglycan (GAG) deposition.

Results: All patients, diagnosed between ages 16 months and 11 years, exhibited multisystem involvement. All had corneal clouding because of GAG accumulation, with PK performed between ages 14 and 22. Visual improvement was limited by optic nerve atrophy despite Enzyme Replacement Therapy. Histopathological analysis revealed hydropic-like changes in basal keratinocytes, intracytoplasmic and subepithelial GAG deposits, and thinned Bowman layer disruption. The stroma displayed elongated deposits, whereas Descemet membrane showed thinning without GAG deposits. Endothelium GAG deposits were also identified.

Conclusions: The study highlights the alterations in various corneal layers, which have seldom been reported on Maroteaux-Lamy syndrome. Nonetheless, the GAG deposits identified and the changes in Bowman layer align with the literature. PK temporarily improved corneal clarity. However, long-term visual outcomes were poor because of optic nerve damage. Early diagnosis and multidisciplinary management are essential to improve outcomes.

Purpose: To compare endothelial cell morphometry, corneal thickness, and transparency of donor corneas during extended hypothermic storage in XTRA4 and Optisol-GS.

Methods: Mate donor corneas were stored in XTRA4 or Optisol-GS at 2 to 8°C for up to 28 days. Endothelial cell density, coefficient of variation (CV), and hexagonality (HEX) were evaluated by specular microscopy. Central corneal thickness (CCT) was measured by Optical Coherence Tomography (OCT). Endothelium quality, stromal edema, and Descemet folds were graded by slit lamp using defined grading scales.

Results: Endothelial cell density, CV, and HEX were similar between cohorts through day 21 ( P > 0.05); however, HEX was higher in the XTRA4 group on the final day ( P = 0.03). Endothelial cell viability was comparable at all time points ( P > 0.05). Initial stromal thickness averaged 520 ± 38 μm (XTRA4) and 502 ± 28 μm (Optisol-GS), with no difference through day 7 ( P > 0.05). Beyond day 7, XTRA4 corneas were significantly thinner (all P < 0.05). Stromal thickness increased over time in both cohorts ( P < 0.05), with a smaller Δ in XTRA4 (15 ± 19 μm) versus Optisol-GS (158 ± 54 μm). Edema scores were similar at baseline (median = 1), although Optisol-GS trended higher by day 21 ( P < 0.001). Descemet folds were fewer in Optisol-GS initially by 1 grade ( P < 0.01) but became more severe than XTRA4 after day 14 (all P < 0.01).

Conclusions: XTRA4 preserves the corneal endothelium similarly to Optisol-GS for up to 14 days while maintaining consistently thinner corneas for up to 28 days. This antiswelling property may improve eye bank logistics and support future laboratory and clinical studies toward extending hypothermic storage beyond the current 14-day limit.

Purpose: Tibial bone keratoprostheses are used in situations where conventional corneal transplantation is not viable. However, the prognosis is often guarded in cases of ocular surface diseases, such as autoimmune conditions or chemical burns, because of the risk of tissue necrosis and subsequent prosthesis extrusion. In this study, we describe an innovative approach using a dermal fat graft to manage keratoprosthesis (KPro) exposure and avoid extrusion.

Methods: We report the case of a man with a history of bilateral chemical burns caused by caustic soda, who underwent tibial bone keratoprosthesis implantation in the left eye. The procedure was later complicated by buccal mucosa necrosis, leading to prosthesis exposure. This was successfully managed with a dermal fat graft. Clinical history, examination findings, imaging, and a literature review are presented.

Results: At 5 years of follow-up, the KPro remained well positioned, with the dermal fat graft fully epithelialized and no evidence of extrusion or other complications. The patient maintained a stable uncorrected visual acuity of 0.3.

Conclusions: This case provides the first evidence of a favorable outcome following dermal fat graft implantation as a treatment for KPro exposure to prevent extrusion. Since KPro extrusion is one of the most frequent postoperative complications, its prevention is of utmost importance. The use of a dermal fat graft in such high-risk cases may offer a more stable and biocompatible solution for long-term prosthesis retention.

Purpose: To investigate the refractive predictability and corneal thickness change after femtosecond laser-assisted lenticule intrastromal keratoplasty (FS-LIKE) or small-incision lenticule intrastromal keratoplasty (SMI-LIKE).

Methods: Pentacam topography and optical coherence tomography measurements were taken of all eyes at 1 day and 1, 3, and 6 months after surgery. Anterior lamellar thickness, lenticule thickness, and posterior lamellar thickness were measured.

Results: The study included 23 eyes (18 patients) that underwent FS-LIKE (n = 12) or SMI-LIKE (n = 11). At 6 months after surgery, the linear regression model suggested superior predictability for the FS-LIKE group (102% correction efficiency) and slight under-correction for the SMI-LIKE group (95% correction efficiency). Compared with preoperative values, the central corneal thickness and the corneal volume were highest on the first postoperative day and subsequently remained stable in both groups. After surgery, the mean lenticule thickness for the FS-LIKE and SMI-LIKE groups were 102.3 ± 29.8 and 114.1 ± 22.5 μm, respectively, which was consistent with planned values. The mean anterior lamellar thickness for the FS-LIKE group was thicker than the planned flap thickness, whereas the value for the SMI-LIKE group was thinner. No significant changes were observed in the posterior lamellar thickness for the 2 groups over the follow-up period.

Conclusions: FS-LIKE could achieve better refractive predictability compared with SMI-LIKE, and the corneal remodeling might explain the difference between the 2 procedures.

Purpose: To report clinical outcomes of cyanoacrylate glue patches in managing corneal melting in keratoprosthesis (KPro).

Methods: Multicenter, retrospective, noncontrolled, interventional case series. Subjects underwent cyanoacrylate glue patches for corneal melt after KPro implantation, regardless of the underlying cause, KPro design, or melt severity. Clinical success was defined as resolving aqueous leak, halting further corneal melting, and avoiding KPro or carrier corneal graft exchange for at least 12 months after cyanoacrylate glue patch application.

Results: Sixteen eyes of 15 patients with KPro underwent a cyanoacrylate glue patch for corneal melting. The mean time from KPro implantation to the development of corneal melt was 49.2 months. Implanted KPro models included Lucia (37.5%) and Boston type 1 with titanium (31.2%) or polymethylacrylate backplate (31.2%). Underlying etiologies for KPro implantation included recurrent graft rejection (56.2%), autoimmune disease (31.2%), and chemical injury (12.5%). A combined procedure with a cyanoacrylate glue patch and amniotic membrane transplantation was performed in 2 cases. The criteria for clinical success were met in 87.5% of patients, with only 2 eyes (12.5%) exhibiting clinical failure. Glue patches were retained successfully for a mean time of 25.50 ± 23.87 months (range: 0-84 months).

Conclusions: Cyanoacrylate glue patches provide a simple, safe, cost-effective, and effective treatment for corneal melts in patients with KPro.