Effect of Platelet-Rich Plasma on Corneal Epithelial Healing after Phototherapeutic Keratectomy: An Intraindividual Contralateral Randomized Study

Comparison of the repeatability and reproducibility of corneal thickness mapping using optical coherence tomography according to tear film break-up time

BACKGROUND

To compare the repeatability and reproducibility of corneal and corneal epithelial thickness mapping using anterior segment optical coherence tomography (AS-OCT) according to tear film break-up time (TBUT).

METHODS

The included eyes were divided into three subgroups according to TBUT (group 1: TBUT ≤ 5 s, group 2: 5 s < TBUT ≤ 10 s, and group 3: TBUT > 10 s). All eyes were imaged separately thrice by two operators to obtain the thickness maps (TMs) of the cornea and corneal epithelium based on spatial zones encompassing a 9-mm-diameter area. Each TM consisted of 25 areas. Intraoperator (repeatability) and interoperator (reproducibility) standard deviations (Sws), coefficients of variation (CoVs), and intraclass correlation coefficients (ICCs) among the tests were calculated and compared in all the areas.

RESULTS

Altogether, 132 eyes of 67 subjects were included (50, 47, and 35 eyes in groups 1, 2, and 3; respectively). The ICCs of corneal epithelial thickness and corneal thickness were > 0.75 in most of the areas. Pairwise comparisons showed that AS-OCT exhibited lower repeatability in group 1 than in groups 2 and 3 (P < 0.05). However groups 2 and 3 showed similar results. Sws and CoVs of corneal epithelial thickness exhibited no significant interoperator differences. While no significant differences were observed in corneal thickness in most of the areas.

CONCLUSIONS

TBUT significantly influences the repeatability of corneal and corneal epithelial thickness measurements. Poor tear film stability requires careful evaluation of corneal epithelial thickness.

Classic lattice corneal dystrophy: a brief review and summary of treatment modalities

PURPOSE

To provide a brief summary and comparison of the most recent literature on available and theorized treatment modalities for classic lattice corneal dystrophy (LCD). This paper aims to support practitioners in their management of this disease.

METHODS

A search was carried out on available literature through PubMed and Google Scholar of English language articles up to January 2023 that relate to the treatment of LCD. Due to scarcity of literature regarding specific novel therapies for LCD, results from other corneal pathologies (granular corneal dystrophy, corneal scarring) are sometimes included for contrast, which is clearly denoted.

RESULTS

LCD is a slowly progressive disease that leads to recurrent epithelial corneal erosions, stromal haze, corneal opacification, substantial discomfort, and visual impairment. Due to its autosomal-dominant inheritance pattern, this disease can persist throughout ancestral lines and requires consistent treatment and follow-up. An optimal management plan is necessary to (1) prolong years of life with best achievable visual acuity; (2) treat painful recurrent corneal erosions as they occur; (3) ensure proper follow-up throughout the life of a patient, as well as monitor at-risk offspring; and (4) monitor efficacy of treatment.

CONCLUSIONS

This paper addresses (1) treatment for early disease including corneal epithelial debridement, photo therapeutic keratectomy (PTK), femtosecond laser-assisted lamellar keratectomy (FLK), and others; (2) treatment for late disease including full thickness keratoplasties and anterior lamellar keratoplasties; and (3) potential future treatment considerations including a wide variety of topical/systemic, genetic, and regenerative approaches.

Advances and prospects of platelet-rich plasma therapy in veterinary ophthalmology

In the recent decades, there has been a significant uptick on the use of platelet-rich plasma (PRP) as a better alternative for ophthalmologic therapies in pathologies, primarily of the ocular surface. PRP is a class of liquid platelet concentrate containing a supra-physiological concentration of platelets in a relatively small amount of plasma. Its potential to heal various tissues has piqued interest in its therapeutic application as a biomaterial in regenerative medicine. It is currently a popular therapeutic agent in plastic surgery, cardiothoracic surgery, reconstructive surgery, and even oral and maxillofacial surgery. Based on the data from in vitro and in vivo studies, it can be concluded that PRP possesses adequate therapeutic potential in ocular pathologies, especially those involving cornea. In addition, the high concentrations of growth factors (TGF-β, VEGF, EGF) present in the PRP accelerate the healing of the corneal epithelium. PRP has great therapeutic prospects in veterinary ophthalmology as a regenerative therapeutic modality. However, several variables are yet to be defined and standardized that can directly affect the efficacy of PRP application in different ophthalmic conditions. There is a shortage of research on the use of PRP in ocular surface defects compared to the number of studies and reports on the use of autologous and allogeneic serum eye drops. Therefore, a data-driven approach is required to generate consensus/guidelines for the preparation, characterization, and therapeutic use of PRP in veterinary ophthalmology. This review aims to inform readers of the latest research on PRP, including its preparation methods, physiological and biochemical properties, clinical applications in veterinary ophthalmology, and their safety and efficacy.

Effect of BIO-PLYTM, a Platelet-Rich Plasma Derived Biologic on PRRSV-2-Infected Macrophages

Porcine Reproductive and Respiratory Syndrome (PRRS) is the one of the most devastating diseases impacting the swine industry worldwide. Control and prevention methods rely on biosafety measures and vaccination. As an RNA virus with a high rate of mutation, vaccines are only partially effective against circulating and newly emerging strains. To reduce the burden of this disease, research on alternative control methods is needed. Here, we assess the in vitro antiviral effect of a novel platelet-rich plasma-derived biologic termed BIO-PLY^TM (for the BIOactive fraction of Platelet-rich plasma LYsate) from both swine and equine origin. Our results show that BIO-PLY^TM significantly reduces the amount of PRRSV viral load determined by RT-qPCR and the number of infectious viral particles measured by TCID50 in infected porcine alveolar and parenchymal macrophages. This study also showed limited toxicity of BIO-PLY^TM in vitro and aspects of its immunomodulatory capacity evaluating the regulation of reactive oxygen species and cytokines production in infected cells. Finally, this study presents promising data on the effect of BIO-PLY^TM on other RNA viruses such as human A influenza viruses and coronavirus.