Hydrogel Placement Research Articles

Treatment of Neural Anosmia by Topical Application of Basic Fibroblast Growth Factor–Gelatin Hydrogel in the Nasal Cavity

A new treatment of neural anosmia. To investigate the effects of basic fibroblast growth factor (bFGF)-gelatin hydrogel on recovery of neural anosmia in mice. Anosmia was induced by intraperitoneal injection of 3-methylindole, 200 mg/kg. One week later, the animals underwent 1 of the following 3 procedures bilaterally: (1) group A: single-shot intranasal drip infusion of phosphate-buffered saline, (2) group B: single-shot intranasal drip infusion of bFGF, and (3) group C: placement of bFGF-gelatin hydrogel in the nasal cavity. The olfactory function of the animal was evaluated by the odor-detection test (ODT) 2 and 4 weeks later. Following the testing, the animal was killed, the thickness of the olfactory epithelium was measured, and the number of olfactory marker protein (OMP)-positive cells was counted. Research installation. Mice. The placement of bFGF-gelatin hydrogel in the nasal cavity. An ODT, thickness of olfactory epithelium, the number of OMP-positive cells The ODT proved that neural anosmia recovered in group C but not in groups A and B. Histologically, olfactory epithelium became thicker and the number of OMP-positive cells increased in group C, while such functional and histologic recovery was poor in groups A and B. These findings suggested that placement of bFGF-gelatin hydrogel in the nasal cavity was an efficient way to facilitate recovery of neural anosmia. As a gelatin hydrogel degrades slowly in the body, bFGF is gradually released around the site of the lesion; thus, it constantly exerts its effects on neural regeneration.

Real‐time tracking of vocal fold injections with optical coherence tomography

Optical coherence tomography (OCT) is a promising new imaging modality that can help discern the layered microstructure of vocal folds. In the future, subepithelial injections of implants will improve vocal fold pliability where there is stiffness of phonatory mucosa. Using OCT both to delineate the depth of subepithelial injections real-time and to serially image the implant over time would be valuable, and has not been demonstrated previously. Ex vivo study using excised calf larynges and survival study using canines in vivo. An investigation was done employing real-time OCT imaging of subepithelial injection pulses into phonatory mucosa of four calf larynges ex vivo to track the presence of subepithelial implants in phonatory mucosa in a survival study using an in vivo canine model. OCT readily identified polyethylene glycol (PEG)-based hydrogel in the subepithelial plane in both the ex vivo calf study and the in vivo canine study. Ex vivo calf images correlated with histological specimens obtained immediately postinjection. Images obtained in this study provide confirmation of the hydrogel injection depth in real time, and allow for the implant to be tracked during a canine survival study. OCT can confirm subepithelial placement of hydrogel implant in the vocal fold with sufficient resolution to provide instantaneous feedback of an injection pulse. Survival studies in an in vivo canine model indicate that OCT can potentially be helpful in monitoring rheologically appropriate implants within the superficial lamina propria.