Diseases of the kidneys, ureters and bladder, with special reference to the diseases of women (1922) (14765585852)

Identifier: diseasesofkidney01kell (find matches)
Title: Diseases of the kidneys, ureters and bladder, with special reference to the diseases of women
Year: 1922 (1920s)
Authors: Kelly, Howard A. (Howard Atwood), 1858-1943 Brödel, Max, 1870-1941 Burnam, Curtis Field, 1877-
Subjects:
Publisher: New York, London : D. Appleton and company



Text Appearing Before Image:
SIMPLE NTTZE CYSTOSrOPE FOR P.LADDER EXAMINATION. 2S7 Optical Principles of the Cystoscope.--Tiik Lkxsks.- Tlic ()i)tieal system ofthe Nitze cystoscopo, wliicli cnii betaken as a type, is shown in Fipire 150. Itis simpler for purposes of understanding to consider tli(^ lenses apart from theprism. As will hv shown, the prism acts exactly as a mirror and transfers theimage of the bladder throngh the lens system. These lenses accomplishthe following optical effects: iirst, the closer the object is to the end ofthe cystoscope the greater its magnifications, and the farther away, the smallerits magnifications; second, an object close to the lens and highly magnified
Text Appearing After Image:
Fig. 151.—Nitze Cystoscope. Showing ocular position of lenses in tube, the prism, thebeak with Mignon light. This is the type of all modern electrical c\stoscopes. can only be seen in part, and the further away the object, the greater theamount of it that can be seen. These facts rest upon the principle that the cys-toscope can ordinarily take in only the field of an angle of from 70 to 80 de-grees. For instance, we all recognize that by this angle of measurement thefinger held close to the eye may be taller than a church steeple a short distanceaway. At a distance of about 3 cm. from the optical part of a cystoscope an ob-ject will seem natural size. At a greater distance it is smaller than natural, andcloser it is larger. The two plano-convex lenses situated near the beak end ofthe shaft make a real upside-down image of the object looked at. In the middleof Hae shaft there is a second convex lens which brings the image to the ocular 288 EXAMINATION OF URINARY TRACT BY NITZE CYSTOS