• To our knowledge, the normal changes that occur in the tympanic membrane after birth have not been described, despite several reports that their otoscopic appearance in healthy, full-term infants is different from that in adults. To provide such a description, the tympanic membranes of 54 temporal bones that had no pathologic evidence of otologic diseases, from patients aged 33 weeks' gestation to 91 years, were examined with light or electron microscopy. The changes encountered in thickness, cellularity, vascularity, collagen, and elastin indicated that the eardrum continues to change beyond the first year of life and into old age.
(Arch Otolaryngol Head Neck Surg. 1991; 117:627-634)
Carlos B. Ruah, Patricia A. Schachern, Daniel Zelterman, Michael M. Paparella, Tae H. Yoon. Age-Related Morphologic Changes in the Human Tympanic MembraneA Light and Electron Microscopic Study. Arch Otolaryngol Head Neck Surg. 1991;117(6):627–634. doi:10.1001/archotol.1991.01870180063013