Postnatal development of the middle ear in New Zealand White rabbits: ossicles and tympanic ring.

We studied the postnatal development of the middle ear (ME) in New Zealand White rabbits. Bullae were scanned using a desktop X-ray microtomograph and 3D models of the ME ossicles as well as the tympanic ring (TR) were prepared. In 0, 1, 2 days old rabbits the ossification process was incomplete.

Perfusion and diffusion limitations in middle ear gas exchange: the exchange of CO2 as a test case.

A long standing debate on perfusion/diffusion limitations in the context of middle ear (ME) gas exchange was revisited using data obtained from previous iso-pressure gas-exchange measurements in different mammals. We tried to determine whether the exchange of CO(2) in the ME is limited by perfusion or by diffusion by comparing the mass specific cardiac output (msQ) and the mass specific initial CO(2) flow rate into air-washed MEs (msV(i) CO(2)) of rabbits and rats. Based on previously published allometry at rest, the msQ was 0.

High-resolution measurements of middle ear gas volume changes in the rabbit enables estimation of its mucosal CO(2) conductance.

Transmucosal CO(2) exchange in the middle ear (ME) of the New Zealand White rabbit (Oryctolagus cuniculus) was studied using an accurate novel detecting and recording system for measuring gas volume changes at constant pressure, based on a principle that was previously used by Kania et al. (Acta Otolaryngol 124:408-410, 2004). After the ME cavity was washed with ambient air, the initial diffusion rate of CO(2) (V(.

Experimental model for investigating trans-mucosal gas exchanges in the middle ear of the rat.

Objective: The total pressure in the middle ear depends on the air composition of this gas pocket, i.e. on gas exchanges occurring through either the Eustachian tube (ET) or mucosa.