Experimental cholesteatoma: a comparison between spontaneous and induced models

Area of Science:

• Otolaryngology
• Experimental Pathology
• Animal Models

Background:

• Cholesteatoma, a destructive epidermal growth in the middle ear, lacks fully elucidated spontaneous and induced animal models.
• Understanding cholesteatoma pathogenesis is crucial for developing effective therapeutic strategies.

Purpose of the Study:

• To compare the incidence and histopathological features of spontaneous cholesteatoma with two induced models in Mongolian gerbils: External Auditory Canal (EAC) obliteration and Auditory Tube (AT) cauterization.
• To evaluate the efficacy of EAC obliteration and AT cauterization in creating reproducible cholesteatoma models.

Main Methods:

• Fifty-four gerbil ears were allocated into three groups: EAC obliteration, AT cauterization, and a control group.
• Histological assessment for cholesteatoma incidence and classification was performed at 2, 4, 8, and 16 weeks post-intervention.

Main Results:

• Cholesteatoma was detected in 30 out of 53 evaluated ears, with a significantly higher incidence in the intervention groups (p<0.0001).
• No significant histological differences were found between cholesteatomas developed in the EAC obliteration and AT cauterization models at similar stages.
• Both induced models demonstrated a higher cholesteatoma incidence compared to the control group.

Conclusions:

• Both EAC obliteration and AT cauterization serve as effective methods for inducing cholesteatoma in gerbils, significantly increasing incidence over control groups.
• Despite differences in induction methods, the resulting cholesteatomas exhibited identical histopathological characteristics at comparable stages.
• These findings support the utility of these induced models for studying cholesteatoma pathogenesis and evaluating potential treatments.