Fireworks Ocular Injury in Saudi Children; Profile and Management Outcomes

Background: To explore the demographic profiling, causes, types, complications, management outcomes, and severity of fireworks- inflicted ocular injuries and traumas in children in KSA.Methods: This is a retrospective study of 115 cases with eye injuries managed at the Emergency Department, of our institution between 2003 and 2019. Demography, clinical features at presentation, mode of management and the Best Corrected Visual Acuity (BCVA) were evaluated at the last follow up. Results: The study included 117 eyes of 115 children [median age: 9 years; 96 (83.5%) boys; 19(16.5%) girls]. Fifty-six (48.7%) participants were bystanders. The injuries were caused mainly due to bangers (n=47; 40.9%), rockets in bottle (n=28; 24.3%), firecrackers (n=27; 23.5%), and nonspecific reasons (n=13; 11.3%). The children had presented with various severity levels: corneal abrasion (n=52; 44.4%); cataract (n=47;40.2%); penetrating injury (n=40; 34.2%); secondary glaucoma (n=22;18.8%); subluxated lens (n=19;16.2%); limbal stem cell deficiency (n=14;12.0%); Iridodialysis (n=12;10.3%), and vitreous hemorrhage (n=11;9.4%). Management interventions of the eyes under study included: penetrating injury repair (n=40; 34.2%), lens removal plus intraocular lens implantation (n=26; 22.2%), removal of foreign body (n=9; 7.7%). The BCVA after six months was 20/20- 20/60 in 49(41%) cases; 20/70 - 20/200 in 27 (23.1%) cases; <20/200-20/400 in 7 (6%) cases, and <20/400 in 34(29.1%) of the cases. Out of 51.3% eyes with <20/200 before management, only 35% recorded severe visual impairment.Conclusion: Fireworks-related eye injuries were mainly observed in boys primarily due to the use of bangers . Visual disability remained in one-third of the managed cases.

Bone Morphogenetic Protein 4 (BMP4) Enhances the Differentiation of Human Induced Pluripotent Stem Cells into Limbal Progenitor Cells

Corneal epithelium maintains visual acuity and is regenerated by the proliferation and differentiation of limbal progenitor cells. Transplantation of human limbal progenitor cells could restore the integrity and functionality of the corneal surface in patients with limbal stem cell deficiency. However, multiple protocols are employed to differentiate human induced pluripotent stem (iPS) cells into corneal epithelium or limbal progenitor cells. The aim of this study was to optimize a protocol that uses bone morphogenetic protein 4 (BMP4) and limbal cell-specific medium. Human dermal fibroblast-derived iPS cells were differentiated into limbal progenitor cells using limbal cell-specific (PI) medium and varying doses (1, 10, and 50 ng/mL) and durations (1, 3, and 10 days) of BMP4 treatment. Differentiated human iPS cells were analyzed by real-time polymerase chain reaction (RT-PCR), Western blotting, and immunocytochemical studies at 2 or 4 weeks after BMP4 treatment. Culturing human dermal fibroblast-derived iPS cells in limbal cell-specific medium and BMP4 gave rise to limbal progenitor and corneal epithelial-like cells. The optimal protocol of 10 ng/mL and three days of BMP4 treatment elicited significantly higher limbal progenitor marker (ABCG2, ∆Np63α) expression and less corneal epithelial cell marker (CK3, CK12) expression than the other combinations of BMP4 dose and duration. In conclusion, this study identified a successful reprogramming strategy to induce limbal progenitor cells from human iPS cells using limbal cell-specific medium and BMP4. Additionally, our experiments indicate that the optimal BMP4 dose and duration favor limbal progenitor cell differentiation over corneal epithelial cells and maintain the phenotype of limbal stem cells. These findings contribute to the development of therapies for limbal stem cell deficiency disorders.

An Analysis of the Progression of Conjunctivalisation after Transplantation of Cultivated Corneal Epithelium

Purpose. To analyse the recurrence of superficial neovascularisation after previous corneal surface reconstruction with cultivated corneal epithelial cells. Materials and Methods. Forty-eight eyes underwent autologous transplantation of cultivated corneal epithelium to treat partial or total limbal stem cell deficiency caused by chemical or thermal injury. The carrier for the epithelial sheets was a denuded amniotic membrane. Follow-up was conducted for up to 120 months. Recurrent revascularisation (measured in terms of clock hours affected) was evaluated with slit-lamp examination and the support of confocal microscopy. Results. During the long-term observation, only 7 eyes had stable epithelia with no neovascularisation from the conjunctiva. Nineteen eyes developed pathologic vessels in 1 quadrant, with additional 4 eyes developing them in 2 quadrants. Twelve patients developed subtotal or total conjunctivalisation of the corneal surface. They were referred for second cultivated epithelium transplantation (3 patients), allogenic keratolimbal transplantation (7 patients), or keratoprosthesis (2 patients). Six patients withdrew consent. The use of confocal scans of up to 100 µm in resolution enabled the detection of pathologic microvasculature originating from the conjunctiva and the exclusion of stromal vascular ingrowth. Conclusions. Local ingrowth of the conjunctiva is a common complication after the transplantation of cultivated epithelial cells. Severe and progressive vascularisation inevitably leads to graft failure. However, if local ingrowth stops before reaching the central cornea, the treatment even with this complication can be considered a success.

Midterm outcomes of penetrating keratoplasty following allogeneic cultivated limbal epithelial transplantation in patients with bilateral limbal stem cell deficiency

AIM: To evaluate the midterm outcomes of penetrating keratoplasty (PK) following allogeneic cultivated limbal epithelial transplantation (CLET) for bilateral total limbal stem cell deficiency (LSCD). METHODS: Ten patients (10 eyes) with bilateral LSCD were enrolled in this prospective noncomparative case series study. Each participant underwent PK approximately 6mo after a CLET. Topical tacrolimus, topical and systemic steroids, and oral ciclosporin were administered postoperatively. Best-corrected visual acuity (BCVA), intraocular pressure (IOP), ocular surface grading scores (OSS), corneal graft epithelial rehabilitation, persistent epithelial defect (PED), immunological rejection, and graft survival rate were assessed. RESULTS: The time interval between PK and allogeneic CLET was 6.90±1.29 (6-10)mo. BCVA improved from 2.46±0.32 logMAR preoperatively to 0.77±0.55 logMAR post-PK (P<0.001). Kaplan-Meier analysis of mean graft survival revealed graft survival rates of 100% at 12 and 24mo and 80.0% at 36mo. PEDs appeared in 5 eyes at different periods post-PK, and graft rejection occurred in 4 eyes. The total OSS decreased from 12.4±4.4 before allogeneic CLET to 1.4±1.51 after PK. CONCLUSION: A sequential therapy design of PK following allogeneic CLET can maintain a stable ocular surface with improved BCVA despite the relatively high graft rejection rate.

PALT (Partial Allogeneic Limbal Transplantation): A New Surgical Technique For Limbal Stem Cell Deficiency

PurposeLimbal stem cell deficiency (LSCD) is a rare but extremely relevant disease of the eye. LSCD patients often require a variety of surgical procedures, including keratoplasty in some cases. However, the outcome of these surgeries, including opacification and revascularization, is often frustrating due to LSCD relapse.MethodsWe developed a new surgical technique for the treatment of LSCD in which partial allogenic limbal transplantation (PALT) is carried out as part of penetrating keratoplasty (PK). After the PK, 1-8 slices from the limbal tissue of the donor graft are prepared and placed under the double running sutures attaching the corneal graft. This procedure was performed on 14 patients with LSCD, caused by severe ocular burn in 5 cases and by infection in 9. Between one and eight limbal transplants were used depending on the extension of the LSCD. ResultsAll 14 patients showed stable or increased visual acuity after the PALT surgery compared to their preoperative visual acuity. All of the grafts were integrated into the superficial corneal layers without progression of corneal vascularization beyond the limbal grafts. The median follow-up period was 12 months on average.ConclusionThe PALT method seems to be a promising surgical procedure for the treatment of patients with LSCD. It can be properly carried out in the context of keratoplasty and does not require a separate donor tissue. The PALT grafts may offer the possibility of constructing a new limbal region, resulting in stable or even increased visual acuity and the absence of corneal vascularization.