Microvasculature of the tympanic membrane

In order to investigate the blood flow of the tympanic membrane (TM) in various conditions, the microvasculature of the TM was observed by scanning electron microscope, using casting methods. Differences in vascular patterns between pars tensa and pars flaccida were observed, suggesting that vascular distribution in TM is closely concerned with the arrangement of radial fibers in the intermediate fibrous layer. Once inflammation was induced, changes in blood vessels quickly took place and most remarkably at the central zone of TM. The TM which closed earlier was found to leak resin at the edge of the perforation. It is proposed that an active blood flow to the perforation edge is necessary for a smooth closing.