[The causes of urodynamic disorders of the urinary tract leading to hydronephrotic transformation].

Experience had with the treatment of 372 patients, admitted to the Clinical Center of Urology--Sofia, and 16 patients--to the Clinic of Urology of the Military Medical Academy, over the period 1990 through 1992, shows that the causes leading to hydronephrotic transformation comprise diseases of congenital and acquired nature involving upper and lower urinary tracts. Congenital disorders affect men and women at an equal male-to-female ratio--1:1, while acquired ones--at 1.8:1 male-to-female ratio; causes located in both upper and lower urinary tract are recorded at a 6.

[The indications and choice for open surgical intervention in hydronephrotic transformation].

Out of the total of 372 patients treated for congenital and acquired hydronephrotic transformations over a three-year period (1990 through 1992), seventeen cases are subjected to treatment with antibiotics and antispasmodics followed by observation, and in 124 cases various types of open pyeloplastic procedures are performed. The indications for operative management of hydronephrotic transformation depends on the results of objective and laboratory studies, and subjective complaints. Accidentally discovered hydronephrotic transformations, I-II degree, may be subjected to conservative management followed by an observation period with good results.

[Drainage (prosthesis) of the pyelocaliceal system].

Of 372 patients, treated in the Clinical Center of Urology-Sofia, and sixteen patients treated in the urological clinic at the Military Medical Academy-Sofia, in 241 cases various types of polyethylene drainage systems and prostheses are used, classified into two basic groups: intraoperative prosthetic replacement, and therapeutic prosthetic replacement. Intraoperative prosthetic replacement of the pyelocaliceal system reduces intrarenal pressure, promotes uneventful operative wound healing, precludes obstruction due to the so-called sterile edema at the site of operation, and serves as a drainage and splint; nephrostoma is indicated in selected cases against the background of additional complications, whereas prosthetic replacement during endourologic manipulations is mandatory. The complications associated with prosthetic replacement of the pyelocaliceal system are rare, and lend themselves readily to nonoperative treatment, but in isolated cases surgical intervention is necessitated.

[The diseases causing stenosis and obstruction of the ureter].

A total of 681 patients with stenosis and obstruction of the ureter (SOU) have been observed over a period of 5 years. The male/female ratio was 1:1.25.

[The modern treatment of stenosis and obstruction of the ureter].

The methods used for treatment of stenosis and obstruction of the ureter (SOU) are: conservative treatment, extracorporal lithotripsy, transureteral operations, surgical management. The different genesis of the nosologic entities underlying--SOU requires adequate effective and organ preserving treatment. In the authors series of 681 patients the mot common approach to treatment und transureteral operations (46.