Histological response to injected dextranomer-based implant in a rat model

Area of Science:

• Biomedical Engineering
• Histopathology
• Urology

Background:

• Dextranomers in sodium hyaluronan (DiHA) are used for submucosal injections.
• Understanding the histopathological effects of DiHA is crucial for clinical applications.

Purpose of the Study:

• To investigate short- and long-term histopathological alterations following submucosal bladder injection of DiHA in a rat model.
• To assess potential migration of DiHA to the brain.

Main Methods:

• Sixty Sprague-Dawley rats were injected with saline (control) or DiHA into the bladder submucosa.
• Rats were sacrificed at 3, 6, and 12 months post-injection.
• Bladder tissue and brain sections were histopathologically examined for inflammation, fibroblast invasion, collagen formation, capillary growth, giant cells, and material migration.

Main Results:

• No DiHA migration to the brain was detected in any group.
• Significant histopathological changes in DiHA-injected bladders included granuloma formation (43.3%), foreign body giant cells (76.6%), 100% inflammatory infiltration, and 100% fibroblast presence around microspheres.
• These changes were observed across all time points.

Conclusions:

• Submucosal DiHA injection induces significant local histopathological reactions in the rat bladder.
• The long-term clinical implications of these reactions, particularly granuloma formation, remain unclear.
• Further prospective studies are needed to clarify the long-term effects for clinical applications.