Cornea最新文献

Purpose: (1) To compare total endothelial cell damage from loading and ejection of Descemet membrane endothelial keratoplasty (DMEK) grafts through Straiko and Lions World Vision Institute (LWVI) glass cannulas. (2) To isolate and quantify endothelial cell damage from loading or ejection alone in Straiko tubes.

Methods: DMEK grafts were peeled, stained with Calcein-AM (CAM), and imaged under fluorescence microscopy to evaluate baseline endothelial damage. Grafts were then loaded and ejected from Straiko and LWVI glass cannulas, and reimaged. Loss of CAM fluorescence signal was evaluated to calculate change in Area of Cell Damage (ACD). ACD changes were compared between Straiko and LWVI cannulas. Custom-made Straiko "half-tubes," consisting of only the loading or ejection end of a Straiko tube, were used to isolate graft loading from ejection, and CAM-based ACD was again assessed.

Results: Loading and ejection resulted in a significant increase in ACD for both Straiko (4.88% ± 0.53%) and LWVI (4.22% ± 0.57%) cannulas, but this was not statistically different between cannulas ( P = 0.42). For Straiko half-tubes, ejection alone (3.08% ± 0.31%) resulted in a significantly greater increase in ACD compared with loading alone (1.38% ± 0.36%) ( P = 0.004).

Conclusions: Ejection of DMEK grafts through a Straiko tube causes more endothelial cell damage than loading. Loading and ejection of DMEK grafts through Straiko and LWVI tubes were associated with similar endothelial cell damage. Bore size alone cannot explain these results. The overall damage, measured using CAM, was lower than previously reported studies that relied on different methods for quantifying damage.

Purpose: To present 4 family members with posterior polymorphous corneal dystrophy (PPCD), nonkeratoconic steep corneas, and myopia caused by a previously unknown genetic alteration in the ZEB1 gene.

Methods: Ophthalmic examinations and corneal curvature analyses were performed for all patients. Whole-exome targeted gene panel sequencing was performed for 1 patient. Pathogenic variant confirmation and segregation of the variant were performed for all 4 patients using Sanger sequencing.

Results: A mother and her 3 children presented with bilateral diffuse corneal opacities, vesicular aggregates at the Descemet membrane level, and endothelial stippling, compatible with the diagnosis of PPCD. All patients had steeper than average keratometry readings with normal globe axial lengths and refractive moderate to extremely high myopia, ranging from -2 to -16.5 diopters (spherical equivalent). The younger patients had more severe findings, with the youngest, an 11-month-old girl, presenting with keratometry readings of 66.72 × 69.48 @ 132 degrees and 66.10 × 67.32 @ 34 degrees in the right and left eyes, respectively. The ZEB1 :c.794-1G>A; chr10-31809053G>A; NM_001174096.2 mutation was detected in all patients.

Conclusions: We describe a novel ZEB1 mutation associated with PPCD, nonkeratoconic steep corneas, and myopia. PPCD3 should be considered not only as an endothelial pathology but also as an ectatic disorder and should be ruled out in young children presenting with high myopia.

Purpose: To report the first known use of combined decellularized Descemet membrane anterior keratoplasty with penetrating keratoplasty (PKP) in a pediatric patient.

Methods: A 2-month-old boy with bilateral sclerocornea underwent bilateral sequential PKP. In the left eye, PKP performed at 2 months of age was complicated by a persistent epithelial defect postoperatively with a 1 month delay in epithelialization. As a result, the patient underwent PKP with a combined decellularized Descemet membrane corneal allograft implantation in the right eye at 3 months of age to enhance early postoperative healing. This was performed by creating a central 3-mm superficial keratectomy before placing Descemet membrane allograft onto the full-thickness graft.

Results: Compared to the 1-month delay in epithelialization after PKP in the left eye, the right eye, which underwent combined PKP and decellularized Descemet membrane corneal allograft, was fully epithelialized by the first postoperative week. The grafts remain clear and intact at 12 months of age. The patient exhibited significant improvement in visual behavior.

Conclusions: This case highlights the successful use of decellularized Descemet membrane anterior keratoplasty in preventing a persistent epithelial defect in the early postoperative period for a pediatric patient with sclerocornea. This may be a viable option for similar pediatric cases with delayed epithelial healing while promoting graft survival and minimizing the need for additional surgical interventions.

Purpose: To investigate the effectiveness and safety of accelerated epithelium-on crosslinking to stabilize tomographically suspicious fellow eyes of young patients with unilateral clinically evident keratoconus (KC) compared with observation alone.

Methods: This retrospective observational study included 43 fellow eyes of 43 young patients with unilateral clinically evident KC who completed a 24-month follow-up. Twenty-four eyes underwent accelerated epithelium-on crosslinking [epi-on corneal crosslinking (CXL) group] and 19 eyes were observed (observation group). A third healthy control group was added for comparison. The primary outcome measures were tomographic parameters and topometric indices assessed by pentacam. Secondary outcome measures included corneal ectatic progression defined as 1-diopter or more increase in maximum or steep keratometry (K max or K 2 ), visual & refractive outcomes, and complications.

Results: Baseline demographic and tomographic characteristics were similar between the epi-on CXL and observation groups ( P > 0.05). Almost all mean tomographic parameters and topometric indices showed insignificant differences between baseline and after 24 months in the epi-on CXL and control groups ( P > 0.05), whereas a significant progression was documented in the observation group ( P < 0.05). At the end of the follow-up, progression was documented in 1 eye (4.2%) and in 8 eyes (42.1%) in the epi-on CXL and observation groups, respectively. Visual and refractive outcomes were more favorable in the epi-on CXL group. No significant complications were reported after accelerated epi-on CXL.

Conclusions: Accelerated epithelium-on CXL was safe and achieved better tomographic stability and less corneal ectatic progression in tomographically suspicious fellow eyes of young patients with unilateral clinically evident keratoconus compared with observation alone.

Purpose: In the past decade, drone use has surged across recreational, commercial, and military sectors, leading to an increase in drone-related injuries, ranging from minor abrasions to severe trauma, such as head injuries and ocular damage. We present the first case of bilateral penetrating ocular injury caused by drone propeller blades, which resulted in significant visual impairment.

Methods: A 45-year-old man presented with bilateral corneoscleral laceration with uveal and vitreous tissue prolapse following an injury with the propeller blades of an agricultural drone. Visual acuity at presentation was light perception in both eyes with inaccurate light projection in the right eye and accurate light projection in the left eye. Bilateral corneoscleral laceration repair was performed under general anesthesia.

Results: The visual prognosis in the right eye was poor because of the involvement of a large scleral tear, which extended posteriorly beyond the equator. The vision in the left eye subsequently improved to 6/24, three months postoperatively.

Conclusions: This case underscores the potential dangers of drones, even in controlled environments, and emphasizes the need for stricter regulations to ensure their safe use and prevent severe injuries, particularly to sensitive areas like the eyes. This case also highlights the importance of proper initial visual assessment, as it can act as a surrogate marker for postoperative visual prognosis.

Purpose: Keratoconus is a progressive corneal ectasia leading to visual impairment. Corneal collagen cross-linking (CXL) is a widely used intervention to halt progression, with 2 main approaches: epithelium-on (Epi-On) and epithelium-off (Epi-Off). This study presents a meta-analysis integrating findings from existing literature and newly analyzed data.

Methods: A systematic search was performed to compare Epi-On and Epi-Off CXL outcomes from 2014 to 2024. Meta-analysis techniques were employed to evaluate the changes in visual and imaging outcomes based on the differences between baseline to available 6-month, 1-year, 2-year, and 3-year follow-up. In addition, subgroup analyses were conducted based on study design (randomized controlled trials vs. non-RCT and observational studies) and risk of bias (high vs. low), using standardized risk assessment tools.

Results: This meta-analysis included 28 studies, covering 1764 eyes including 875 (49.6%) Epi-Off and 889 (50.4%) Epi-On treated eyes. Maximum keratometry flattening was observed at 6 months (ES = 0.183, P = 0.039), became more pronounced at 1 year (ES = 0.639, P = 0.004), and remained significant at 2 years (ES = 0.377, P <0.001). Central corneal thickness significantly reduced after Epi-Off treatment at 6 months (ES = 0.327, P = 0.012) and 1 year (ES = 0.247, P = 0.040) more than Epi-on group. In addition, spherical equivalent improved significantly at 2 years (ES = -0.395, P = 0.048). In contrast, no significant differences were observed in steepest keratometry, average keratometry, best-corrected distance visual acuity, and uncorrected distance visual acuity between the 2 groups across all follow-up durations. Subgroup analysis supported the robustness of structural outcomes in Epi-Off, particularly in lower risk, observational studies and nonrandomized clinical trials, whereas functional outcomes remained not significant.

Conclusions: Epi-Off CXL demonstrates superior topographic and tomographic improvements compared with Epi-On, although visual acuity outcomes remain equivalent. These findings support a personalized approach in selecting CXL technique based on patient profile and treatment goals.

Purpose: Conjunctival autografts (CAGs) are the gold standard treatment after pterygium resection, but it is challenging to achieve consistently thin Tenon-free CAGs with manual dissection. We herein report the reproducibility and clinical outcomes of a novel algorithm to produce customizable trapezoidal CAGs using femtosecond laser (femtosecond lasers)-assisted pterygium surgery.

Methods: We first tested this algorithm in 4 pig eyes to show reproducibility. We then treated 15 pterygia of 14 patients using this algorithm. After manual pterygium excision, 7-mm x 10-mm preset trapezoidal CAGs were dissected with the Ziemer FEMTO LDV Z8 laser set at a 60 μm depth. The achieved thickness was measured with intraoperative optical coherence tomography, and the achieved area was calculated.

Results: For the pig eyes, the average CAG length and width were 9.8 ± 0.1 mm and 7.3 ± 0.04 mm, respectively, with a mean deviation of 7.3% ± 3.2% and 7.5% ± 4.1%, respectively. The mean age of the patients was 56.8 ± 7.3 years. The programmed and achieved CAG areas were 70 mm 2 and 72.5 ± 3.9 mm 2 , respectively, with a mean deviation of 4.7% ± 4.6%. The eventual CAG thickness was 59.5 ± 3.9 μm, with a minimal deviation of 4.4% ± 4.6%. The average time to remove the FSL-prepared CAG to unfold it onto the cornea was 19.9 ± 14.9 seconds. At the postoperative month 3 follow-up, no postoperative complications or recurrences occurred, and all donor CAG sites had completely healed.

Conclusions: This novel algorithm using the FEMTO LDV Z8 in Femtosecond Laser-Assisted Pterygium Surgery provides consistent and customizable trapezoid ultrathin CAGs. Longer follow-up and larger cohorts will need to be studied for recurrence and complication rates.

Purpose: To assess the frequency and histopathological features of stromal corneal dystrophies. In addition, we sought to evaluate the concordance between the clinical diagnoses provided by ophthalmologists and the pathological reports.

Methods: We retrospectively analyzed all cases of stromal corneal dystrophies between 1996 and 2022. Data were collected from pathological reports of corneal buttons obtained from penetrating keratoplasties (PK). Clinical and pathological diagnoses along with demographic information were recorded. Concordance between clinical and pathological diagnoses was assessed using frequency analysis and Cohen kappa coefficient.

Results: Histopathological review of 1440 corneal specimens from PK revealed 56 (3.8%) stromal corneal dystrophies in 53 patients. The most common dystrophy found was lattice corneal dystrophy (LCD), present in 30 specimens (53.6%), followed by granular corneal dystrophy type 2 in 14 specimens (25.0%), granular corneal dystrophy type 1 in 7 specimens (12.5%), and macular corneal dystrophy in 5 specimens (8.9%). Concordance between clinical and pathological diagnoses was observed in 37 of 45 cases, resulting in an overall concordance rate of 82.2% with a Cohen kappa coefficient of 0.64.

Conclusions: The concordance rate of 82.2% and Cohen kappa coefficient of 0.64 indicate strong agreement between clinical and pathological diagnoses of stromal corneal dystrophies. However, despite ranking as the second most common dystrophy, the absence of clinical diagnoses for granular corneal dystrophy type 2 highlights the critical need to use both Masson Trichrome and Congo red stains when granular or lattice-like deposits are present in the cornea to ensure precise and reliable diagnosis.