Comparison of Photochemical Crosslinking Versus Sutures for Bonding Conjunctival Grafts

Abstract

Background and ObjectivesTo explore whether Rose Bengal‐induced photochemical crosslinking (RB‐PCL) can be a replacement for sutures in conjunctival autograft bonding, we compared the safety, operating time, postoperative ocular signs, and inflammatory responses of RB‐PCL versus nylon suturing for sealing conjunctival autografts in rabbits.Study Design/Materials and MethodsThirty‐six New Zealand White rabbits underwent limbal conjunctival autografting using either sutures or RB‐PCL to attach conjunctival autografts to the bare sclera. Animals were randomized to one of two groups (18 per group): the suture group or RB‐PCL group. Photochemical crosslinking with a wavelength of 532 nm green light with an illumination intensity of 0.6 W/cm2 for 250 seconds (150 J/cm2) or suturing was performed followed by light examination at 3, 7, 28 days after surgery to evaluate the healing condition. Rabbits in each group were euthanized on day 3 (n = 6), 7 (n = 6), or 28 (n = 6) postoperatively, and the graft tissues from the surgical site were processed to evaluate inflammatory response by assessing protein levels of tumor necrosis factor α (TNF‐α), and interleukin 6 (IL‐6) as well as histological examination. Cell viability was evaluated by counting both total and dead cells on hematoxylin and eosin (H&E) stained tissue samples from both groups at 3 and 7 days after surgery. The surgery procedure time was recorded and the graft surface temperatures were measured before and after illumination.ResultsPhotochemical crosslinking effectively secured the limbal conjunctival autograft over an ocular conjunctival defect with no significant difference from the suture group. The time required for this light activated bonding method was ~550 seconds in comparison with the suture method of half hour. The differences of measured temperature on the graft surface before and after RB‐PCL treatment were 2.98 ± 0.11°C. The induction of IL‐6 and TNF‐α protein was remarkably reduced in the RB‐PCL group compared with the suture group at 3 and 7 days after surgery. Histology revealed less infiltrated neutrophils were observed in the RB‐PCL group than in the suture group at 3 and 7 days postoperatively. Furthermore, the RB‐PCL group showed a better healing process with less eye discharge and mild conjunctival congestion. No significant difference in percent dead cells was observed between RB‐PCL and suture groups at 3 and 7 days after surgery.ConclusionsRB‐PCL is a promising alternative for bonding the conjunctival autograft with shorter operation time, less inflammation and better healing outcomes compared to conventional suture. Thermal damage and phototoxicity were not observed using the RB‐PCL method in bonding conjunctival grafts. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Comparison of Photosensitized Tissue Bonding and Vet Glue in Closure of Incisional Wounds

“…The regenerative process of an injury depends on coordination of four stages (Fung et al 1999;Islam et al 2014;Ruprai 2019) i.e. hemostasis and coagulation stage (Gomes et al 2019) in which clotting of blood occurs to minimize blood loss (Wang et al 2019;Unsihuay et al 2021), inflammatory stage starts inflammatory reactions and removes the waste of dead cells (Feng et al 2020;Wang et al 2020;Lee et al 2022), proliferatory stage initiates within few days of wound and involves reconstruction of connective tissues, starts production of denovo network of circulatory system and construction of epithelium (Redmond and Kochevar 2019;Narayanan et al 2020;Noori-Dokht et al 2022;Yelkuvan et al 2023) and maturation phase (Yan et al 2022) which causes refurbishing of collagen form III to form I (Basov et al 2019; Fuentes-Lemus and Lopez-Alarcon Li et al 2021;Liu et al 2022;Liang et al 2023). Maturation phase involves the formation of scar and may last up to a year or more (Sarabi et al 2021;Wanasingha et al 2021;Klelemen et al 2022;Lee et al 2023).…”

New developments in the treatment of corneal ectatic disorders

“…Beyond the cornea, CXL has also been applied to other ocular structures, sometimes anecdotal, sometimes with great potential. For example, anecdotal reports of RF/UVA or RB/GL CXL of tarsus [187][188][189][190] , during glaucoma surgery [191][192][193][194][195][196] , and of amniotic grafts 165,[197][198][199][200][201][202] exist.…”