Spontaneous healing of the tympanic membrane after traumatic perforation in rats
Marcos Miranda de Araújo1, Adriana Andrade Batista Murashima1, Vani Maria Alves2
1Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo (USP), Ribeirão Preto, SP, Brazil.
Unlabelled:
The most common etiologies of tympanic membrane perforation are infections and trauma.
Objective:
The objective of the present study was to assess the healing of traumatic tympanic membrane perforation in rats.
Methods:
The tympanic membrane from male Wistar rats was perforated in the anterior and posterior portions to the handle of the malleus. Five tympanic membranes were evaluated 3 days after tympanic perforation; 5 after 5 days; 5 after 7 days; 3 after 10 days; and 4 after 14 days. The tympanic membranes were submitted to histopathological evaluation after hematoxylin-eosin staining.
Results:
Tympanic membrane closure occurred at about 7-10 days after injury and the healing process was complete by day 14. The proliferative activity of the outer epithelial layer was present close to the handle of the malleus and to the tympanic annulus.
Conclusion:
The spontaneous healing process of the tympanic membrane starts from the outer epithelial layer, with later healing of the lamina propria and the mucosal layer.
Insights
Traumatic tympanic membrane perforation in rats heals spontaneously. The outer epithelial layer initiates healing within 7-10 days, completing by day 14.
Area of Science:
- Otolaryngology
- Regenerative Medicine
- Histopathology
Background:
- Tympanic membrane perforations commonly result from infections or trauma.
- Understanding the healing mechanisms is crucial for clinical management.
Purpose of the Study:
- To investigate the spontaneous healing process of traumatic tympanic membrane perforations.
- To evaluate the timeline and cellular activity during tympanic membrane repair in a rodent model.
Main Methods:
- Male Wistar rats underwent surgical perforation of the tympanic membrane.
- Tympanic membranes were histopathologically evaluated using hematoxylin-eosin staining at various time points (3, 5, 7, 10, and 14 days post-injury).
Main Results:
- Spontaneous closure of traumatic tympanic membrane perforations was observed between 7 and 10 days.
- Complete healing was achieved by day 14.
- Proliferative activity was noted in the outer epithelial layer near the malleus handle and tympanic annulus.
Conclusions:
- Spontaneous tympanic membrane healing originates from the outer epithelial layer.
- Subsequent healing involves the lamina propria and mucosal layers.
- This study provides insights into the natural regenerative capacity of the tympanic membrane.
