URETHROGRAPHY

URETHROGRAPHY (from Greek urethra-urinary passage and grapho-I write), a method for obtaining X-ray images of the contours of the urinary passage after preliminary distension of its lumen with a contrast substance (liquid or gaseous). Cunningham first applied U. in 1910. This method was subsequently thoroughly developed by Langer. As a contrast substance, a 20% solution of sodium bromide heated to body temperature, 20% iodipin, thorotrast, abrodil, sergozin, or air is usually used. The patient is placed on his back. One leg is abducted in an extended position, while the other, bent at the hip and knee joints, is slightly rotated outward. The pelvis is turned so that it forms a 40° angle on the side of the bent leg. The central ray is directed to the base of the penis, which is stretched parallel to the thigh of the bent leg. The contrast substance is introduced into the urethra from a Janetsky syringe with a Tarnowski rubber tip attached. The X-ray is taken twice—during the introduction of the contrast liquid, when the anterior part of the urethra is sufficiently distended, and during the act of urination after preliminary introduction of 150-200 cm³ of contrast solution into the bladder. The second X-ray gives a clear image of the distended posterior part of the urethra. The normal anterior urethra appears along the cavernous part as a uniform strip with parallel edges. The bulbar part of the urethra is expanded along the lower wall, forming a convex downward arc. The posterior part of the urethra, when filled from the syringe, appears as a narrow strip, forming a straight or slightly more than straight angle, extending to the bladder floor, which is located at the level of the symphysis or slightly above it. Sometimes a small filling defect in the shape of an elongated oval is visible, corresponding to the seminal hillock. In pathological cases, U. makes it possible to see changes in the urethral lumen. U. acquires special significance in congenital anomalies—double urethra, paraurethral passages, diverticula, helping not only in diagnosis but also in clarifying the details of surgical intervention. In urethral strictures, U. makes it possible to determine the number of narrowed areas, their location, the condition of the urethra proximal to the strictures, etc. All the features mentioned in each case have practical value, and their recognition by other methods is usually impossible. For all the listed lesions, it is recommended to perform U. with liquid contrast substances. For urethral stones and polyps, especially those located in the anterior part, it is more advisable to use air, as this enhances the contrast of the stone or polyp. In addition, air does not cause irritation of the mucous membrane.