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Dive into the research topics where Jan Breza is active.

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Featured researches published by Jan Breza.


The Journal of Urology | 1989

Detailed anatomy of penile neurovascular structures: surgical significance.

Jan Breza; Sherif R. Aboseif; Bradley R. Orvis; Tom F. Lue; Emil A. Tanagho

In 10 formalin-preserved adult male cadavers, dissection of the penile veins, arteries and nerves revealed information of clinical importance. The main venous drainage of the corpora cavernosa is via the cavernous veins, with additional drainage through the circumflex, deep dorsal, and crural veins. The arterial supply of the cavernous bodies varied remarkably, and the incidence of an accessory internal pudendal artery was high. The cavernous nerves, previously believed to be microscopic structures, were in fact identifiable grossly, and we were able to follow them from the region of the hilum of the penis to the prostate. The nature of these nerves was then confirmed by serial histologic sectioning. This detailed knowledge of the venous drainage and arterial and nervous supply of the penis, as well as of the relationships among the cavernous structures in the hilum of the penis, can elucidate the cause of erectile dysfunction and provide a valuable guide for surgical correction of vasculogenic and neurogenic impotence.


Urology | 1994

Is colchicine effective in Peyronie'sdisease? A pilot study

Emre Akkus; Jan Breza; Serge Carrier; Ates Kadioglu; Jamil Rehman; Tom Lue

OBJECTIVES The treatment of Peyronies disease with oral or topical agents has not been entirely satisfactory. In this pilot study, we hypothesized that colchicine, known to induce collagenase activity and decrease collagen synthesis, might be an ideal agent in the treatment of Peyronies disease. METHODS Colchicine was administered orally for 3 to 5 months to a group of 24 previously untreated patients with Peyronies disease. RESULTS Peyronies plaque decreased or disappeared in 12 of the 24 patients, 7 of 9 patients with painful erections reported significant relief, and penile curvature was improved in 7 of 19 cases. Erectile status, narrowing of the penis, and accompanying Dupuytrens contracture did not change in any of the cases. CONCLUSIONS Although this pilot study shows some promising results of the use of colchicine in the treatment of Peyronies disease, the ultimate usefulness of this agent will be determined only by a prospective double-blind clinical study.


The Journal of Urology | 1993

High Flow Priapism: A Spectrum of Disease

Gerald Brock; Jan Breza; Tom F. Lue; Emil A. Tanagho

We describe 4 cases of high flow arterial priapism, ranging from 1 week to 3 years in duration. The mode of presentation, evaluation using a duplex scanner, treatment and ultimate resolution are discussed. In 1 patient treated with ice compression the erection subsided spontaneously. One patient underwent percutaneous embolization and achieved detumescence. In 2 men a vascular pseudocapsule formed around the site of the ruptured cavernous artery that provided an important anatomical landmark for intraoperative localization. The ruptured branch of the cavernous artery was ligated in an open procedure. Based on these cases and a review of the literature, we outline a modified diagnostic and therapeutic approach for patients with high flow arterial priapism.


The Journal of Urology | 1989

Erectile Response to Acute and Chronic Occlusion of the Internal Pudendal and Penile Arteries

Sherif R. Aboseif; Jan Breza; Bradley R. Orvis; Tom F. Lue; Emil A. Tanagho

We designed two animal experiments to elucidate the effect of obstruction of the internal pudendal artery on erectile function. In five dogs the internal pudendal or penile artery was acutely clamped unilaterally or bilaterally with a non-crushing vascular clamp. In eight dogs, the internal pudendal or penile artery was ligated, unilaterally or bilaterally, and occlusion was maintained for two months. In both models, electrodes were implanted around the cavernous nerves for electroerection. In unilateral occlusion, blood flow in the contralateral internal pudendal artery was recorded via an ultrasonic probe. In both unilateral and bilateral occlusion, intracavernous pressure in both corpora cavernosa was recorded through a 21-gauge butterfly needle connected to a Statham transducer. In the chronic model, selective pudendal angiography was done after the erection study was completed; the dogs were then sacrificed and the penile tissue was examined histologically under light microscopy. Unilateral acute clamping of the internal pudendal or penile artery caused a compensatory increase in arterial flow in the contralateral pudendal artery with only moderate impairment of intracavernous pressure on the ipsilateral side, but bilateral occlusion resulted in a marked reduction in the intracavernous pressure response to neurostimulation. In contrast, chronic obstruction of penile vessels had a minimal effect on erectile function due to the development of a rich network of collaterals around the penis. Histological evaluation revealed mild local changes in the cavernous tissue with characteristic compensatory enlargement of branches of the cavernous artery on the control side in cases of unilateral occlusion.


The Journal of Urology | 1989

Local and systemic effects of chronic intracavernous injection of papaverine, prostaglandin E1, and saline in primates

Sherif R. Aboseif; Jan Breza; Ruud Bosch; Francois Benard; Christian G. Stief; Walter Stackl; Tom F. Lue; Emil A. Tanagho

To compare the local and systemic effects of chronic intracavernous injection of papaverine, prostaglandin E1, and saline on erectile tissue, eight pigtail monkeys underwent 75 injections over a nine-month period. Monkeys were divided into three groups; each group received papaverine (10 mg.), prostaglandin E1 (20 micrograms.), or saline (one ml.). The erectile response was closely observed for two hours after each injection to monitor the onset, degree, and duration of erection. Liver function tests were performed every three months to detect early systemic metabolic changes. After sacrifice, the simian penises were perfused in situ and examined histologically with both light and electron microscopy. Papaverine resulted in an initially strong erectile response, but this was maintained throughout the length of the study in only two monkeys. In contrast, prostaglandin E1 resulted in tumescence that was maintained in all monkeys over the nine-month period. In addition, the papaverine group had elevated liver enzymes and significant histologic changes with loss of normal architecture on both light and electron microscopy. The other two groups showed only minimal histologic changes or none.


The Journal of Urology | 1990

The Effect of Venous Incompetence and Arterial Insufficiency on Erectile Function: An Animal Model

Sherif R. Aboseif; Ulrich Wetterauer; Jan Breza; Francois Benard; Ruud Bosch; Christian G. Stief; Tom F. Lue; Emil A. Tanagho

We designed an animal model to elucidate the effect of venous leakage and arterial insufficiency on erectile function. In 10 dogs, electrodes were implanted around the cavernous nerves for electroerection and blood flow in the internal pudendal artery was recorded. Venous leakage was mimicked by inserting needles of varying gauges (30 to 16G) into the corpus cavernosum and the erectile response to neurostimulation was recorded before and after the creation of the leak. The relationship between the size and the amount of the venous leakage, the changes in the intracavernous pressure (peak and drop), and the changes in the peak and maintenance arterial blood flow were documented. Arterial blood flow was then reduced by 25 and 50 per cent by means of a screw clamp on the terminal aorta. The erectile response to neurostimulation was again determined, with the same electrical parameters, first with reduced blood flow alone, then in combination with leakage of varying size. Our results showed that minor cavernous vein leakage in the presence of normal arterial flow and a healthy sinusoidal system had a minimal effect on erectile function owing to a compensatory increase in penile blood flow. However, when reduction of arterial blood flow was superimposed on venous leakage, even of a minor degree, the erectile response to neurostimulation was markedly impaired.


Urology | 1994

Improved hemodynamic response after long-term intracavernous injection for impotence

Gregory A. Marshall; Jan Breza; Tom F. Lue

OBJECTIVE To investigate the phenomenon of spontaneous erections in patients on long-term intracavernous injection therapy. METHODS We undertook an objective assessment of the penile circulation of 35 patients; 21 used prostaglandin E1 (PGE1) alone and 14 used a combination of papaverine, phentolamine, and PGE1. All underwent duplex ultrasonography before initiation of home self-injection and again after a mean of thirty-one months of treatment (most patients performed injections once or twice a week). RESULTS The diameter of the cavernosal arteries did not change significantly after treatment. However, the mean peak flow velocity increased highly significantly (P < 0.001): 17.9 cm/second in the right cavernous artery and 21.2 cm/second on the left before treatment; 24 cm/second on the right and 29 cm/second on the left after treatment. More than one third (13 of 35 patients [35%]) achieved functional erection without injection at least some of the time, giving clinical support to the sonographic findings. CONCLUSIONS We suggest that the combination of vasodilatory drugs and sexual stimulation may act to improve sinusoidal and penile arteriolar smooth muscle function.


The Journal of Urology | 1993

Intracavernous sodium nitroprusside : inappropriate impotence treatment

Gerald Brock; Jan Breza; Tom F. Lue

On the basis of reports describing nitric oxide as a form of endothelium-derived relaxing factor and on our own experience with intracavernous use of nitric oxide-releasing substances in animal models, we undertook an approved human study of intracavernous sodium nitroprusside as a treatment for impotence. We report our early experience in which severe hypotension and only mild tumescence in our first 3 patients caused us to discontinue the trial.


World Journal of Urology | 2010

Improvement of histopathological classification of adrenal gland tumors by genetic differentiation

Torsten Gruschwitz; Jan Breza; Heiko Wunderlich; Kerstin Junker

PurposeThere are often problems in differentiating between benign and malignant adrenal gland tumors by imaging and histopathology. Fine-needle biopsy is possible but not used owing to problems in histopathological differentiation. On account of considerable differences in the therapy and aftercare of benign and malignant adrenal tumors, correct classification of tumor type is of greatest importance. The purpose of this study was to define specific genetic alterations differentiating between adenomas and carcinomas.MethodsDNA was isolated from tumor areas in paraffin sections and amplified by a modified protocol for DOP-PCR. After labeling of tumor-DNA and normal DNA with biotin-dUTP and digoxigenin-dUTP, respectively, comparative genomic hybridization (CGH) was carried out according to standard protocols. Retrospectively, 26 (16 adenomas and 10 carcinomas) tumors of the adrenal cortex were analyzed.ResultsGenetic alterations were found in 5/16 adenomas (31.25%) and in all adrenocortical carcinomas. The mean number of genetic changes per tumor was 8.7 (range 6–12) in carcinomas. The benign cortical tumors present 1.6 changes (range 0–3) per tumor. Only a moderate correlation between number of alterations and size of tumor was seen. Furthermore, specific chromosomal alterations of carcinomas were identified.ConclusionsGenetic evaluation facilitates differentiation between adrenal gland tumors. Genetic tests should be used in routine diagnostics of adrenal specimens. Potentially, fine-needle biopsy can be established as standard diagnostics of adrenal tumors with unknown genesis.


Urology | 1990

Cavernous vein arterialization for vasculogenic impotence: An animal model

Jan Breza; Sherif R. Aboseif; Tom F. Lue; Emil A. Tanagho

We designed acute and chronic animal models to evaluate a new procedure of arterialization of the cavernous vein. In the acute study, arteriogenic impotence was induced in 6 dogs by bilateral ligation of the penile arteries just proximal to the crus of the penis. The cavernous vein and penile artery were anastomosed proximal to the site of ligation, and the pudendal vein was ligated proximally to prevent the diversion of arterial blood away from the penis. Erection was induced either by electrostimulation of the cavernous nerves or by intracavernous injection of papaverine, and the erectile response was studied before and after cavernous vein arterialization. Four dogs were followed up for two months to evaluate the long-term effects of the procedure. Shortly after arterialization of the cavernous vein, the basal flow rate in the internal pudendal artery increased dramatically to almost six times the control rate, and the erectile response to neurostimulation was approximately 85 percent of control. Selective pudendal arteriography at two months confirmed the patency of all arteriovenous anastomoses. However, scanning electron microscopy and histologic examination revealed sinusoidal damage most probably consequent to the chronically elevated arterial flow.

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Tom F. Lue

University of California

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Ruud Bosch

University of California

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Anup Patel

University of California

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Gerald Brock

University of California

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