TRANSPARENT CHAMBER 

 TECHNIQUE 



Williams, Anat. Rec, 1930, 47, 187). 

 It makes possible a microscopic study 

 of the original tissues of the ear, with 

 their original nerve, blood vessel and 

 lymphatic vessel supply. 



A third type, termed the "moat cham- 

 ber", developed by Abell and Clark 

 (Anat. Rec, 1932, 53, 121; and Abell, 

 Anat. Rec, 1937, 69, 14) contains 

 a small space, or "moat", accessible 

 to the outside, in which may be placed 

 any fluid substance, in order to ob- 

 serve, through the micrscope, the effect 

 upon the tissues. The fluid may be 

 withdrawn later, for chemical analysis. 

 This chamber, in Abell's hands, has 

 been used for studies on the absorption 

 of methylene blue, reactions to a phos- 

 phate buffer, rate of absorption of urea, 

 rate of diffusion from blood vessels of 

 nitrogenous substances, reaction of 

 blood vessels to foreign protein in a 

 sensitized animal (Abel and Schenck), 

 and behavior of vessels in hypertension 

 (Abel and Page). 



A fourth type, named the "removable 

 top" chamber has been developed by 

 R. G. Williams, for the purpose, origi- 

 nally, of obtaining easy access to the 

 living tissue of the chamber, in order 

 that transplants of organs or tissues, 

 or implantation of granular substances, 

 might be made, without seriously dis- 

 turbing the delicate tissues. It con- 

 tains a device by which the top cover 

 may be temporarily lifted off merely by 

 unscrewing two or three nuts. This 

 chamber has undergone steady improve- 

 ment. The original model (R. G. 

 Williams, J. Morph., 1939, 65, 17) was a 

 modification of the "moat" chamber- 

 constructed of glass and mica. This 

 was improved (R. G. Williams, Anat. 

 Rec, 1948, 101, 291) by the substitution, 

 for glass, of tantalum — the metal which 

 is practically inert in contact with 

 living tissues — and the replacement of 

 a major part of the relatively large, 

 flat surface that comes in contact with 

 living tissue, by a tantalum gauze, 

 which becomes virtually a part of the 

 ear. Finally Williams and Roberts 

 (Anat. Rec, 1950, 107, 359) have intro- 

 duced a fifth type of chamber, a radi- 

 cally modified tantalum and mica 

 chamber, which still further reduces the 

 flat surfaces next living tissue, has a 

 longer life than any other type of 

 chamber (although many "round-table" 

 and "moat" chambers have survived 

 well over a year), is so little irritating 

 to the ear that outer splints and shields 

 have been found unnecessary, can be 

 installed in much less time than is re- 

 quired for other chambers, gives beau- 

 tiful pictures of blood capillary growth 



353 TRANSPARENT CHAMBER 



TECHNIQUE 



and behavior, has a removable top for 

 transplanting, could be modified to 

 study preformed tissue, and has been 

 adapted for the introduction or removal 

 of fluids, for which the "moat" cham- 

 ber was devised. Epidermis, which 

 forms an annoying temporary invader 

 of "round-table" chambers in about 

 one-fourth of installed chambers, never 

 invades the latest tantalum chambers. 

 On the other hand, up to the present, 

 neither nerves nor lymphatics, which 

 have been studied in "round-table" 

 chambers, have been seen in the new 

 type chambers, although these tissues 

 could probably be brought in by slight 

 modifications of the chamber. Success- 

 ful autogenous transplants have been 

 made by Williams in one or the other 

 variety of his ingenious chambers, of 

 thyroid, adrenal cortex, spleen, lymph 

 node and testis, many of which have 

 survived and have been available for 

 microscopic study for months, and even 

 for 3-ears (cf. Am. J. Anat., vols. 62, 

 77, 81, and Anat. Rec, vols. 73, 104, 

 179). 



In other laboratories, Ebert, Florey 

 and Pullinger (J. Path, and Bact., 

 1939, 48, 379) have described a "round- 

 table" chamber, modified chiefly by the 

 substitution of another plastic, "per- 

 spex", for celluloid, and the use of a 

 vertical instead of an oblique access 

 hole in the base. They give an excel- 

 lent description of the entire method of 

 construction and installation of the 

 chambers. Ebert, Ahern and Block 

 (Science, 1949, 110, No. 2868, p. 665) 

 describe further modifications, using 

 the same or a similar plastic, namely 

 "plexiglas" (acrylic and methacrylate 

 resin), which include a reduction in 

 outside diameter from 32 to 25 mm. (a 

 dimension also used by Essex); replace- 

 ment of "buffers" by remote supports 

 (as in Sandison's chambers); replace- 

 ment of metal bolts and nuts by plastic 

 rods; elimination of splints and shields; 

 and a quadruple punch, guided by a 

 double, transparent template, which is 

 very helpful in installing chambers. 

 Essex, H. E. (Methods in Medical 

 Research, Year Book Publishers, 1948, 

 1, 139) gives again a complete descrip- 

 tion of the construction and installa- 

 tion of a chamber made of "lucite" 

 (methyl methacrylate resin), modelled 

 after the Ebert, Florey, Pullinger style 

 of "round-table" chaml)er. He studies 

 the ear with the rabbit in its normal 

 position, rather than on its back. 



On account of the greater ease of 

 construction, greater clearness and 

 freedom from warping, we have tried 

 lucite in our laboratory, but it has been 



