Blood Vessels on Reissner's Membrane

Abstract

The purpose of this paper is to investigate in detail the prevalence, localization, and course of the vessels in Reissner's membrane in the well-developed cochleae of individuals of various ages. 1) Of 181 prenatal and postnatal temporal bone specimens, 36 bones (19.9%) showed a total of 43 blood vessels along the surfaces of Reissner's membrane on the scala vestibuli side. In relation to age, 15 vessels were found in 12 out of 16 bones (75%) in the 15-week-old fetus group; 19 vessels were present in 15 out of 58 bones (25.8%) in the 0–1 year age group; 8 vessels were seen in 8 out of 55 bones (14.2%) in the 1–10 year age group; and only 1 vessel was found in 1 out of 52 bones (1.9%) in the 10–102 year age group. 2) Of the 43 vessels, 41 were present in the apical turn, and the remaining 2 vessels were located in the the upper half of the middle turn. 3) There were two types of courses followed by the vessels on Reissner's membrane. Among the 43 vessels observed, 3 vessels ran over the surface of the membrane all the way from the area near the spiral limbus to the vestibular crest. The remaining 40 vessels ran across the fluid space of the scala vestibuli, attached to the membrane somewhere between the spiral limbus and the vestibular crest, and then took their courses along the membrane up to the area of the vestibular crest. 4) The cause of death of the 22 postnatal individuals with vessels on Reissner's membrane was studied. Fifteen individuals expired from congenital anomalies of the heart, brain, digestive organ, lung, or kidney. Among these, congenital heart anomaly cases occurred with an extremely high rate (66.6%). 5) The vessels on Reissner's membrane appeared to occur as an element in the incomplete development of the cochlea. They seemed to be in the process of devascularization, mostly in the first decade, in both the congenital anomaly cases and the noncongenital cases.