Usefulness and Safety of 0.4% Sodium Hyaluronate as a Submucosal Injection Solution in Rabbits

다국어 초록 (Multilingual Abstract)

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) with submucosal saline injection are well-established methods for excising nonpolypoid early neoplastic lesions of the gastrointestinal tract in humans. In EMR and ESD, this submucosal injection forms a bulla that lifts the lesion, provides a safety cushion during resection, and reduces the risk of perforation. Commonly used solutions include normal saline (NS), 10% glycerol, and 0.4% sodium hyaluronate (SH). Among these, 0.4% SH is the most preferred solution in humans due to its slow absorption. While the usefulness of EMR and ESD in humans has been well-documented, information on its application in veterinary medicine remains limited. This study aimed to compare the usefulness and safety of 0.4% SH with 10% glycerol and NS as a gastric submucosal injection solution in rabbits with goals of providing a veterinary perspective on the application of submucosal injection solutions and highlighting the clinical relevance for endoscopic procedures in animals. A conventional gastrotomy was performed to expose the gastric lumen, followed by a submucosal injection. In macroscopic evaluations of mucosal elevation using a digital caliper, 0.4% SH showed a statistically significant elevation effect compared with NS, unlike 10% glycerol. Histomorphometric analysis further revealed that 0.4% SH maintained submucosal space expansion for the longest duration. In addition, histopathological analysis showed no tissue damage except for hemorrhage across all of the submucosal injection groups. In conclusion, 0.4% SH is considered the most preferable submucosal injection material in veterinary medicine, particularly for its usefulness and safety. Based on the results of this study, minimally invasive techniques such as EMR and ESD are expected to be applicable in animals. This study provides the first veterinary-specific evaluation of 0.4% SH as a submucosal injection solution in endoscopic resection (ER), demonstrating its potential benefits in minimally invasive endoscopic procedures. The findings suggest that 0.4% SH may enhance the safety and efficacy of ER, making it a preferable choice for submucosal injection in this context in veterinary medicine.