Labyrinth Membranous

Meniere s disease is a condition in which there is increased volume of endolymph with dilatation of the membranous labyrinth. It is brought about by excessive production of endolymph or impaired outflow from the labyrinth. It is characterised by attacks of vertigo, tinnitus, nausea and vomiting. 

Fig. 31. (A) Rat duodenum stained for alkaline phosphatase with azo dye method (B5a). Semidense particles of azo dye are deposited in the plasma membranes of the microvilli X70,000. (B) Placental labyrinth cell reacted for alkaline phosphatase with the cadmium method (M22). Deposits are related only to the cell surface X56,000. (C) Brush border of proximal tubule cell of the kidney showing deposits of final product related to the surface of the microvilli. Cadmium method of Mizutani and Barrnett (M22) X 35,000. Electron micrographs, courtesy of R. J. Barrnett.

The snail-shaped cochlea, located in the temporal bone of the skull, contains a bony labyrinth and a membranous labyrinth. The bony labyrinth consists of the otic capsule (the external shell) and the modiolus (the internal axis). The membranous labyrinth, coiled inside the bony labyrinth, consists of three adjacent tubes the scala vestibuli, the scala media, and the scala tympani (O Figure 4-1). The scala vestibuli and the scala media are separated by Reissner s membrane the scala media and the scala tympani are separated by the basilar membrane and part of the osseous spiral lamina. The scala vestibuli and the scala tympani are filled with perilymph, a fluid whose ionic composition is similar to that of cerebrospinal fluid. The fluid sealed inside the scala media, the endolymph, contains a high concentration of potassium. 

The capillary bed should be regarded as continuous in all three dimensions, and in the intervillous space the maternal blood channels resemble a labyrinth of canals with diameters of capillary dimensions (27). At the level of exchange, fetal and maternal blood may be considered to flow in similar channels, but the maternal channel is free of an enclosing membrane and is bounded by the villi of the capillary bed. 

The membranous labyrinth is relatively easier to represent in three dimensions than the bone labyrinth since data are directly acquired by MR. The initial method applied to MR for 3D display of the labyrinth was the MIP (maximum intensity projection). The final image that is obtained represents a projectional roadmap of the labyrinthine components. The simplicity of using MIP has made it the most widely used algorithm for 3D imaging even in this case but since MIP results from summed inten-... 

We also performed a study (Neri et al. 2005) on 3D CT and MR co-registration in the assessment of cochlear implantation (Fig. 10.7). The main advantage of CT-MR fusion is the matching of the electrode and its natural location, which is the membranous labyrinth along the scale tympani. We tried to imagine a visualization method that was able to display not only the electrode itself, but was also capable of showing the real anatomical boundaries of the electrode within the surrounding structures of... 

Figure 6.18 Top Chemical wave in the BZ reaction propagating through a membrane labyrinth. The wave was initiated at the lower left corner of the 3.2 x 3.2 cm maze. Bottom Velocity field showing local propagation direction obtained from analysis of fifty images obtained at 50-s intervals. Lines show shortest paths between five points and the starting point S. (Reprinted with permission from Steinbock, O. Toth, A. Showalter, K. 1995. Navigating Complex Labyrinths Optimal Paths from Chemical Waves, Science 267, 868 871.

Von Hippel-Lindau disease predisposes to the development of various tumors (hemangioblastomas of the neuraxis and retina, tumors of the membranous labyrinth, renal clear cell carcinomas or cysts, pheochromocytomas, pancreatic cysts or tumors, and epididymal cystadenomas). Renal cancer constitutes one of the main causes of death (Richard et al. 1998). Conversely, meta-analysis of cases of coincident tuberous sclerosis complex shows that the risk of malignancy is comparable with the normal population (Tello et al. 1998). 

Coagulant is dissolved to an appropriate concentration in 4 concrete tank each with 13.5 m capacity. The coagulant solution is then transferred to tanks by membrane dosing pumps. Each coagulation line has 2 labyrinth Mixing Chambers (MC) and each reinforced concrete MC has five inclined baffles which create turbulent flow. The retention time of Mixing Chambers is 3 minutes. 

Ear the entire human hearing apparatus, consisting of three parts middle ear or tympanic cavity, membrane and eustachian tube, and the inner ear or labyrinth. 

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