Animal Model of Chronic Tympanic Membrane Perforation

Abstract

Chronic tympanic membrane perforations (TMP) can be a source of significant morbidity from hearing loss, recurrent middle ear infections, changes in lifestyle, and risk of cholesteatoma formation. Laboratory experiments of TMP have been fraught by the rapid and high rate of spontaneous healing observed in animal models. There is controversy on the minimal time that perforations in animal models must have in order to be considered chronic TMP and thus have clinical relevance, with authors suggesting time periods of perforation patency of 8–12 weeks. In this article, we sought to create a clinically significant experimental model that could yield a high rate of perforation patency for at least 8 weeks. Animals undergoing acute TMP were exposed to three different experimental situations to delay the healing of the perforation: fractionated radiation, topical lipopolysaccharide application, and a combined dexamethasone and mitomycin C (DXM/MC) solution. In our study, the use of DXM/MC reliably produced TMP lasting at least 8 weeks in 86.48% of the cases without the need to reopen the perforation, infolding the edges of the membrane, or using physical barriers to prevent TMP closure. Histologically, the resulting perforated tympanum showed hyaline changes of the remnant tympanum and hyperkeratosis of the squamous epithelia of the external auditory canal. We believe that this model is reproducible and has potential use in experiments of delayed healing of TMP. Anat Rec, 303:619–625, 2020. © 2019 American Association for Anatomy

Non-Invasive Optical Screening of Streptococcus Pneumonia Based Inflammatory Changes of the Tympanic Membrane and Mastoid Mucosa in Guinea Pig Otitis Media Using Optical Coherence Tomography

“…Therefore, a less number of ex vivo specimens were involved in this study preliminarily. Although the number of specimens is less, the feasibility was sufficiently confirmed through the obtained quantitative and qualitative results and precisely verified with previously reported histological and quantitative assessments [18], [30], [31], [40]- [42]. Nevertheless, using the current results to determine a threshold parameter confirmed through a P value analysis is challenging due to the lack of in vivo assessments.…”

Decellularized tympanic membrane scaffold with bone marrow mesenchymal stem cells for repairing tympanic membrane perforation

“…A 50%‐sized perforation was made on the anterior half of the TM using a syringe tip through eardroscopy. A chronic TMP animal model was prepared as described previously 18 . Combined with local application of mitomycin C/dexamethasone, a gelatin sponge soaked in mitomycin C (0.5 mg/ml) was placed on the perforation of the TMP for 10 min and was then removed.…”

“…A chronic TMP animal model was prepared as described previously. 18 Combined with local application of mitomycin C/ dexamethasone, a gelatin sponge soaked in mitomycin C (0.5 mg/ml) was placed on the perforation of the TMP for 10 min and was then removed. A second gelatin sponge soaked in dexamethasone (5 mg/ml) was placed over the perforation for 10 min and removed.…”

The Dorsal Skinfold Chamber as a New Tympanic Membrane Wound Healing Model: Intravital Insights into the Pathophysiology of Epithelialized Wounds

“…Laceration of rodent tympanic membranes leads to regular spontaneous closure within weeks [ 34 , 35 , 36 , 37 ]. Therefore, various methods of mechanical and biochemical attenuation of spontaneous closure have been reported (e.g., thermal myringotomies, epithelialized flaps, and topical mitomycin/corticoid) [ 3 , 18 , 32 , 38 , 39 , 40 , 41 , 42 ]. Still, the resulting defect size is not standardized, and wound attenuation may interfere with wound treatment.…”