Embryonic Tissue in the Midle Ear and Mastoid: Report of Two Cases

Neonatal Mesenchyme Temporal Bone Study: Typical Receding Pattern Versus Increase in Potter's Sequence

“…The presence of kidney, lung, and ear anomalies in Potter's sequence suggests that lung hypoplasia may be due to an abnormality of some systemic factor acting in both the lung and the ear,lSJg rather than the currently accepted mechanical concept; too little amniotic fluid (oligohydramnios) interferes with lung growth through the physical restriction of respiratory movements.20.21 Interestingly, although there is a variation in the mesenchyme volume among the patients, there is practically no difference between the right and left ears in each case (Figs. 7,8). Such symmetry between ears strengthens the suspicion that the amount of residual mesenchyme is not a random event, but that the ears respond equally to unknown systemic influences.…”

Development of the Middle Ear in Neonatal Chinchillas. I. Birth to 14 Days

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Abnormalities of the Neonatal Ear: Otoscopic Observations, Histologic Observations, and a Model for Contamination of the Middle Ear by Cellular Contents of Amniotic Fluid

“…11 Crowe and Polvogt reported temporal bone findings of 2 men aged 53 years and 63 years, which they interpreted as demonstrating a substantial amount of mesenchyme. 12 Takahara, et al recently provided histologic normative data of mesenchyme.l Fifty-three temporal bones without anomalies obtained from 41 patients, 26 weeks to 8 years of age, were selected. The authors discovered that the amount ofmesenchyme decreased in volume with increased postpartum maturity and nearly had disappeared within the first year.…”

“…8 Crowe and Polvogt have postulated that residual mesenchyme in middle aged men as demonstrated on temporal bone histology was a cause of their hearing loss. 12 The timing of the mesenchymal resorption is varible. The development of the middle ear space as a consequence ofmesenchymal disappearance has been reported from before term 8 to approximately 1 year.…”

“…1 • 7 However, adult patients with persistent mesenchyme have been reported. 12 By histologic evaluation, an effort was made in select cases to assess whether there would be a reasonable likelihood that the volume of mesenchyme could influence the appearance of the tympanic membrane by pneumatic otoscopy. Further, an effort was made to see if a specific condition or conditions was associated with a significant persistence of the mesenchyme.…”