Evaluation of corneal epithelial wound healing after penetrating keratoplasty in patients receiving a new matrix therapy agent (regenerating agent)

The landscape of clinical trials in corneal regeneration: A systematic review of tissue engineering approaches in corneal disease

The limited availability of a healthy donor cornea and the incidence of allograft failure led researchers to seek other corneal substitutes via tissue engineering. Exploring the trend of clinical trials of the cornea with the vision of tissue engineering provides an opportunity to reveal future potential corneal substitutes. The results of this clinical trial are beneficial for future study designs to overcome the limitations of current therapeutic approaches. In this study, registered clinical trials of bio-based approaches were reviewed for corneal regeneration on March 22, 2024. Among the 3955 registered trials for the cornea, 392 trials were included in this study, which categorized in three main bio-based scaffolds, stem cells, and bioactive macromolecules. In addition to the acellular cornea and human amniotic membrane, several bio-based materials have been introduced as corneal substrates such as collagen, fibrin, and agarose. However, some synthetic materials have been introduced in recent studies to improve the desired properties of bio-based scaffolds for corneal substitutes. Nevertheless, new insights into corneal regenerative medicine have recently emerged from cell sheets with autologous and allogeneic cell sources. In addition, the future perspective of corneal regeneration is described through a literature review of recent experimental models.

Neurotrophic keratopathy: General features and new therapies

Neurotrophic keratopathy is an uncommon degenerative corneal disorder characterized by compromised corneal sensory innervation resulting in the formation of epithelial defects and nonhealing corneal ulcers. Various treatment modalities are available to stabilize disease progression, improve patient well-being, and prevent vision loss. For eligible patients, medical and surgical reinnervation have emerged as pioneering therapies, holding promise for better management. We present a comprehensive review of the disorder, providing an update relevant to ophthalmologists on pathogenesis, diagnosis, treatment options, and novel therapies targeting pathophysiological pathways.

First-Intention Incisional Wound Healing in Dogs and Cats: A Controlled Trial of Dermapliq and Manuka Honey

This study aimed to compare incisional wound healing in cats and dogs after the topical application of Μanuka honey and a new medical device, Dermapliq. Comparisons were made between each treatment and control, between the two treatments, and between dogs and cats. Twelve cats and twelve dogs were included in this study, and the impact of the two substances was examined through cosmetic, clinical, ultrasonographical, and histological evaluation. The use of Dermapliq in first-intention wound healing achieved a significantly better cosmetic evaluation score and better total clinical score at days 20-41, compared to the control, in both dogs and cats. The ultrasonographically estimated wound area was smaller with Dermapliq compared to the control. Wounds treated with Dermapliq showed histologically less inflammation compared to the control. The use of Manuka honey did not show a significantly better cosmetic score compared to the control. Skin thickening was significantly higher after using Manuka honey compared to the control and so was the total clinical score. However, the median wound area, as was evaluated ultrasonographically, was significantly smaller when wounds were treated with Manuka honey, the difference being more apparent in dogs. Dermapliq was proven to be a better choice in achieving favorable wound healing than Manuka honey in dogs and cats in first-intention healing. In our study, cats had a statistically better cosmetic score and less skin thickening and scar width compared to dogs. Histologically, cats showed significantly less edema, higher inflammation and angiogenesis scores, and lower fibroblast and epidermis thickening scores when compared to dogs.

Clinical applications of bioengineered tissue-cellular products for management of corneal diseases

PURPOSE OF REVIEW

To discuss bioengineered tissue-cellular products for treatment of corneal diseases that are currently in clinical use. These include tissue-cellular products that have received regulatory approval, are being used off-label in clinical practice, or are in active use in clinical trials.

RECENT FINDINGS

Due to the global shortage of donor corneal tissue, significant efforts have been made to develop bioengineering tissue-cellular products that can replace or augment the use of cadaveric tissue for corneal transplantation. The development of carrier substrates to support transplantation of cultivated limbal epithelial transplantation (CLET) has been a growing area of research. CLET offers a promising therapeutic alternative to conventional simple limbal epithelial transplantation and keratolimbal allografts for treatment of limbal stem cell deficiency. Engineered tissue matrices and porcine-derived corneas are potential alternatives to human donor tissue in anterior lamellar keratoplasty for corneal ulcers and scars, as well as intrastromal transplants for advanced keratoconus. For endothelial disease, substrate supported cultured endothelial cell grafts, and synthetic barrier devices are promising alternative to traditional endothelial keratoplasties.

SUMMARY

There has been increasing interest in cellular and acellular bioengineered tissue-cellular and synthetic products for treatment of corneal diseases, and many of these products have already seen clinical use. Industry and academia have important roles in advancing these products to later phase clinical trials and comparing them to conventional allograft approaches. Future development of full thickness donor corneas with cultivated epithelium, endothelium, and stromal keratocytes in a biosynthetic matrix will likely be an important next step in tissue alternatives. Continued progress in this field will be critical for addressing the global disease burden from corneal blindness.

A nano-phytochemical ophthalmic solution for marked improvement of corneal wound healing in healthy or diabetic mice

Aim: To formulate a novel nano-phytochemical ophthalmic solution to promote corneal wound healing. Methods: Dipotassium glycyrrhizinate (DG) and palmatine (PAL) were used to formulate this formulation marked as DG-PAL, and its efficacy and mechanisms for promoting corneal wound healing were evaluated in mice. Results: DG-PAL was easily fabricated with excellent physical profiles. In in vivo efficiency evaluations, DG-PAL demonstrated an excellent promoting effect on corneal epithelial/nerve wound healing in both healthy and diabetic mice. These effects were involved in the DG-PAL-induced decreased expression levels of HMGB1 and its signaling-related factors in the corneas and trigeminal neurons of the healthy or diabetic mice. Conclusion: DG-PAL possibly represents a promising ophthalmic solution for promoting corneal wound healing.

Effect of 2% Hyaluronic Acid on the Rate of Healing of Corneal Epithelial Defect After Pterygium Surgery: A Randomized Controlled Trial

Purpose

The study aimed to investigate the effects of 2% hyaluronic acid (HA) on corneal epithelial defect after pterygium surgery in comparison with the control group, measured in terms of the healing rate of corneal epithelial defect and pain score after surgery.

Methods

In this double-blind randomized clinical trial, fifty patients with primary pterygium were randomized into 2 groups: a control group or the group treated with a single topical application of 2% HA. Comprehensive ophthalmological examinations included measuring the area of corneal epithelium defect using ImageJ freeware and the pain score assessment after the operation.

Results

The mean and SD of the area of epithelial defect measured on postoperative Day 0, 1, and 2 were 10.89 ± 1.33 mm², 5.04 ± 0.87mm², and 2.44 ± 0.74 mm² for the HA group, and 11.14 ± 1.11 mm², 7.74 ± 1.17 mm², and 5.31 ± 1.15 mm² for the control group, respectively. While the initial area of the defect on Day 0 was essentially the same for both groups (p = 0.478), the area of the defect in the HA group was significantly smaller on both Day 1 and Day 2 (p < 0.001, p < 0.001), respectively. Similarly, the HA group exhibited a statistically significant higher rate of healing for the cornea epithelial defect over Day 0 and 1 compared to the control group (5.85 ± 0.89 mm²/day vs 3.14 ± 1.28 mm²/day, p < 0.001), respectively. The median (range) pain scores were evaluated at Day 0 was 7 (4–10) in the HA group and 7 (3–10) in the control group (p = 0.953). There was no statistically significant difference between two groups (p > 0.05) for Days 1, 2, and 3.

Conclusion

A single topical application of 2% HA tended to accelerate the healing process of corneal epithelium defect after pterygium surgery without any observable adverse effects during short-term follow-up.

Comparative Analysis of Matrix-Regenerating Agent and Corneal Cross-Linking in an Experimental Alkali Burn Rabbit Model

PURPOSE

This study aimed to investigate the clinical and histopathological effects of corneal cross-linking (CXL) and matrix-regenerating agent (RGTA) treatments after corneal alkali burn.

MATERIALS AND METHODS

Twenty-four alkali-burned corneas from 24 rabbits were divided into three groups: control, CXL, and RGTA. All animals were investigated for epithelial healing, opacification, ulceration, and neovascularization at days 1, 7, 14, and 21 after the alkali burn. Corneas were excised and sent for histological examination on day 21.

RESULTS

One animal each from the CXL and control groups exhibited moderate ulceration, while no ulceration was observed in the RGTA group. No significant difference was observed among the groups in corneal thickness or corneal opacity measurements at the final visit (p = .058 and p = .544, respectively). Both RGTA and CXL treatments were effective in terms of epithelial healing and neovascularization (p = .023 and p = .03, respectively). On histological examination, the CXL and RGTA groups were more effective in treating epithelial loss, stromal edema, corneal vascularization, and leukocytic infiltration than the control group (p < .05). The immunohistochemical staining scores of the CXL and RGTA groups for caspase-3, vascular endothelial growth factor, and matrix metalloproteinase-9 in the epithelium and stroma were significantly lower than those in the control group (p < .05). In the immunohistochemical examination for inducible nitric oxide synthase, epithelial staining scores were similar among the groups (p > .05). In contrast, the stromal staining scores of the CXL and RGTA groups were lower than those of the control group (p < .05).

CONCLUSION

Both CXL and RGTA therapies were effective in reducing anatomical and histopathological complications after corneal alkali burn. Further investigation is needed to determine the optimal timing, duration, and dosage of these treatments.

Matrix Regenerating Agent (RGTA) in a Neurotrophic Corneal Ulcer

Neurotrophic keratopathy is a condition associated with corneal damage and impaired corneal healing. There are no specific treatments available for this disease and current treatments are not associated with improved visual function. Matrix regenerating agents (RGTA) are recent topical agents showing positive results in the treatment of several corneal conditions, including neurotrophic keratopathy.

We report the case of a 73-year-old patient with a neurotrophic ulcer treated with RGTA.

Treatment with RGTA allowed complete corneal healing and a dramatic recovery in visual function in our patient. RGTA solutions are an important and safe therapeutic option for the treatment of selected corneal pathology.