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R Hartung

Publications and source records attributed to R Hartung.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Validity of iohexol clearance in patients with chronic renal failure and normal renal function in comparison to (99m)Tc-DTPA-clearance].

BACKGROUND AND OBJECTIVE: The most common method used for testing dynamic renal function is creatinine clearance, but it has some limitations, e. g. variable muscle mass and tubular secretion of creatinine. The use of radionuclides as an exact method is limited in terms of availability, cost and time needed for examination. We compared the plasma clearance of iohexol with the established (99m)Tc-diethylenetriaminepentaacetate acid (DTPA) clearance. The aim of the present study was to validate iohexol clearance as a simple and suitable method for measuring to determine GFR with a comparable sensitivity to radioisotopic methods. METHODS: 120 patients (49 females, 71 males), mean age of 56 (range 20 to 84) years with normal renal function and different stages of renal failure, mean creatinine clearance of 61.6 +/- 44,9 (range 1.8 - 181.1) ml/min/1.73 m2 received a bolus injection of 10 ml iohexol, a non-ionic low osmolar x-ray contrast medium. Using the one-compartment model, plasma samples were taken after 150, 240 and 480 minutes. The total plasma disappearance of iohexol was measured by x-ray fluorescence analysis and the clearance was calculated. The (99m)Tc-DTPA clearance was determined in accordance with a standard protocol. RESULTS: A high correlation was found between the clearance of iohexol and (99m)Tc-DTPA (r = 0.95). The average deviation between Iohexol and (99m)Tc-DTPA clearance was 7.4 ml/min/1.73 m2. Allergic and nephrotoxic side effects were not observed. CONCLUSION: Iohexol clearance is a valid method for measuring GFR in patients at any stages of renal failure. It is easy to perform and inexpensive.

Adult↗
PubMed2003

[Pseudoaneurysm of a subsegmental renal artery after percutaneous nephrolitholapaxy].

At postoperative day 10 of a percutaneous nephrolitholapaxy for a large stone in the right renal pelvis of a 78-year-old female patient, persistent gross hematuria, requiring blood transfusions, occurred. Selective renovasography showed a pseudoaneurysm of the branch of a segmental artery close to the lower renal calices. Subsequent selective placement of two "steel-coils" in the feeding artery through a coaxial catheter system resulted in complete and stable occlusion without loss of renal parenchyma. Thereafter, bleeding immediately stopped and the patient suffered no further complications. This tool of interventional radiology should be kept in mind before open surgery is considered.

Aged↗
PubMed2003

Significance of random bladder biopsies in superficial bladder cancer.

OBJECTIVES: We investigated to what extent biopsies of normal-appearing urothelium taken from patients with superficial bladder cancer (Ta, T1, Tis) showed malignant disease and whether those findings had impact on therapeutical decisions. PATIENTS AND METHODS: 1033 consecutive patients presenting with Ta, T1 or Tis (carcinoma in situ) superficial bladder tumors at increased risk for recurrence underwent multiple random biopsies from normal-appearing urothelium during transurethral resection (TUR). Patients with small, primary, singular tumors (smaller or equal to 1cm) were excluded from random biopsies. RESULTS: No tumor was found in the random biopsies of 905 patients (87.6%). 128 patients (12.4%) showed urothelial bladder cancer in their random biopsies (Tis: 74, Ta: 41, T1: 12, T2: 1). In 14 patients, where transurethral resection of the primary tumor revealed no signs of malignancy, urothelial bladder cancer was detected in the random biopsy material: Ta 8 patients, Tis 5 patients and T1 one patient. 21 patients with Ta tumors and 29 patients with T1 disease showed concomitant Tis. Upstaging of the primary, resected tumor by histological examination of the random biopsy material occurred in 75 patients (7%). Altogether, due to the random biopsy results therapy was altered in 70 patients (6.8%) of our series: It changed intravesical chemotherapy to BCG in 45, provoked a second TUR in 48 and cystectomy in 15 patients. CONCLUSIONS: While the clinical significance of random biopsies is still controversial, random biopsy results had strong impact on therapeutical decisions in our series. Regarding random bladder biopsies a simple tool for the urologist to identify high risk groups of patients, we recommend them as part of the routine management of superficial bladder cancer.

Adult↗
PubMed2003

Electrocautery: principles and practice.

We explain the basic physics of transurethral resection of the prostate (TURP). Modifications of electrodes or high-frequency units that should improve TURP are discussed. Finally, we introduce Coagulating Intermittent Cutting (CIC), which is a TURP using a modified high-frequency generator. Results of in vitro experiments and the first data from a multicenter trial are demonstrated.

Animals↗
PubMed2002

[Significance of endorectal nuclear magnetic resonance tomography and transrectal ultrasound diagnosis in local staging of prostatic carcinoma].

METHODS: We assessed the staging accuracy of endorectal magnetic resonance imaging (eMRI) and transrectal ultrasonography (TRUS) for localized prostate cancer. 54 patients with biopsy proven prostate cancer underwent TRUS and eMRI prior to radical retropubic prostatectomy. The MR images were prospectively interpreted by two radiologists. These findings were compared with the histopathological results. RESULTS: Overall accuracy of eMRI in defining local tumor stage was 93% by radiologist A and 56% by radiologist B. Overall accuracy by TRUS was 63%. Analysis of interobserver agreement showed a poor correlation regarding MRI studies. Endorectal MRI was more sensitive than TRUS for detecting capsular penetration and seminal vesicle involvement. TRUS revealed a relatively high specificity and was superior to eMRI in this regard. CONCLUSION: This series shows the current limited value of TRUS and eMRI for planning treatment in patients with clinically localized prostate cancer.

Aged↗
PubMed2002

[Virtual endoscopy of the urinary tract].

This review article depicts the technique of virtual uro-endoscopy and its diagnostic value and highlights future aspects. The raw data are acquired using CT, MR, or ultrasound. Sufficient contrast between the wall of the hollow organ and its interior is reached by administering gas or contrast medium into the bladder or injecting contrast media i.v. After processing of these data, virtual endoscopic procedures can be watched on a screen in the same way as a cine-film of a conventional endoscopic operation. Virtual endoscopy is a reliable method with a high sensitivity for pathologies larger than 0.5 cm. It is not invasive, and there are situations that cause difficulties in conventional endoscopy (e.g. gross hematuria, diverticula, strictures) that cause no technical problems in virtual endoscopy. Problems encountered in virtual endoscopy are due to its poor sensitivity for pathologies smaller than 0.5 cm, for carcinoma in situ, and for ureteral calculi. So far there are no routine-indications for virtual endoscopy in urology. Nevertheless, it can be of additional value in diagnosis providing the indications are carefully controlled. In future, virtual endoscopy will probably become integrated into the spectrum of urologic diagnostics investigations.

Contrast Media↗
PubMed2001

Oral intake of poppy seed: a reliable and simple method for diagnosing vesico-enteric fistula.

PURPOSE: In up to 50% of patients with vesico-enteric fistula conventional diagnostic methods fail. We report a simple and low cost diagnostic method that involves the oral intake of poppy seed. MATERIALS AND METHODS: From 1994 to 1999, 17 patients in whom vesico-enteric fistula was suspected underwent the poppy seed test. We administered 250 gm. poppy seed orally in the evening and the urinary excretion of poppy seed was evaluated during the next 2 days. RESULTS: Of the 17 patients 11 excreted the black seeds in the urine for 2 days after oral intake of the seeds. The diagnosis was supported by conventional diagnostic methods in 9 of the 11 cases, while in the remaining 2 the poppy seed test was the only preoperative diagnostic procedure that proved the existence of a fistula. The diagnosis was confirmed by surgical exploration in all 11 patients. In the remaining 6 patients with a nonspecific complaint vesico-enteric fistula was excluded by conventional diagnostic techniques and by the success of nonoperative therapy. CONCLUSIONS: The oral intake of poppy seed is a simple and ready available method for diagnosing vesico-enteric fistula. It may support the surgeon decision when conventional diagnostic tools fail.

Humans↗
PubMed2001

Incidence and outcome of patients with adrenal metastases of renal cell cancer.

OBJECTIVES: To evaluate the outcome of patients with adrenal metastasis in renal tumors to establish the oncologic necessity of adrenalectomy in these patients. Radical nephrectomy for renal cell cancer includes simultaneous ipsilateral adrenalectomy. Recent reports suggest that adrenal involvement in renal cell cancer is rare and can be predicted by computed tomography or distinct algorithms. METHODS: In a retrospective analysis of 866 consecutive patients who underwent nephrectomy and adrenalectomy, we established the rate of adrenal metastasis and obtained follow-up information to evaluate disease outcome. RESULTS: We calculated an adrenal metastasis rate of 3.1% (n = 27); of these 27 patients, only 6 (0.7% of all patients) presented with a solitary adrenal metastasis. Kaplan-Meier analysis demonstrated that patients with solitary adrenal and multiple metastases have a poor outcome. The median survival of patients with localized renal cancer was 43.9 months compared with 21.3 months for patients with a solitary adrenal metastasis and 11.0 months for patients with multiple metastases. CONCLUSIONS: Ipsilateral, solitary, and synchronous metastases in renal cell cancer are rare and patients have a poor outcome despite surgical resection. Therefore, simultaneous adrenalectomy can be omitted during radical nephrectomy if the preoperative examinations or algorithms used do not predict adrenal metastasis in the patient with renal cell cancer.

Adrenal Gland Neoplasms↗
PubMed2001

The ability of the American Joint Committee on Cancer Staging system to predict progression-free survival after radical prostatectomy.

OBJECTIVE: To examine, in a retrospective analysis of outcome based on prostate-specific antigen (PSA) levels, whether the 1992 and revised 1997 staging criteria for prostate cancer can be used to predict progression-free survival for patients after radical prostatectomy for pT2 and pT3 prostate cancer. PATIENTS AND METHODS: In all, 291 patients with a PSA determination during a 6-month interval after radical prostatectomy were analysed (mean follow-up 5.2 years). In the absence of a uniform system of pathological staging, the histopathological stage was defined according to the 1992 and 1997 American Joint Cancer Committee/Union Internationale Contre le Cancer (AJCC/UICC) tumour-nodes-metastases (TNM) staging classification. Findings were correlated with the PSA value after surgery. The subgroups of pT2 and pT3 disease were compared for the time to PSA progression, using Kaplan-Meier data analysis and the log-rank test. RESULTS: The biochemical progression-free 5-year survival rates for stage pT2 were 83% (pT2a), 81% (pT2b) and 62% (pT2c); there were no significant differences in the pT2 subgroups. The recurrence-free rates for pT3 were 79% (pT3a), 65% (pT3b) and 50% (pT3c); the actuarial recurrence-free rate was significantly different for patients with 1997 AJCC pT3a vs pT3b disease (P=0.0132). There was no significant difference in the 1992 AJCC stages pT2a vs pT2b (P=0.1232) and the recurrence-free rate was not significantly different for patients with 1992 AJCC pT3a vs pT3b disease (P=0.9). There was a significant difference in the likelihood of a PSA relapse between patients with positive and negative surgical margins (P=0.131). CONCLUSION: These results support the current revised 1997 AJCC/UICC staging system for prostate cancer. There is an urgent need to develop a pathological equivalent to the AJCC/UIC TNM clinical staging system. Greater clinical input and evaluation from different institutions are essential to reach consensus on pathological staging categories that maximize the predictability of outcome after definitive therapy. Crucial issues are the definition and quantification of extraprostatic extension and definition of surgical margin categories.

Disease Progression↗
PubMed2001

Limited value of endorectal magnetic resonance imaging and transrectal ultrasonography in the staging of clinically localized prostate cancer.

OBJECTIVE: To examine the role of endorectal magnetic resonance imaging (eMRI) and transrectal ultrasonography (TRUS) for clinically localized prostate cancer and to assess interobserver agreement in interpreting MRI studies. PATIENTS AND METHODS: Fifty-four patients with biopsy-confirmed prostate cancer underwent TRUS and eMRI before radical retropubic prostatectomy. The MR images were prospectively interpreted by two radiologists with special expertise in this field. The criteria evaluated prospectively in each patient were extracapsular extension (ECE) and seminal vesicle invasion (SVI). The results were correlated with the histopathological findings after radical prostatectomy. RESULTS: At pathology, 27 patients had stage pT2, 15 had stage pT3a and 12 had stage pT3b lesions. The overall accuracy of eMRI in defining local tumour stage was 93% by radiologist A and 56% by radiologist B; the overall accuracy by TRUS was 63%. There was a poor correlation for the MRI studies between observers. The eMRI was more sensitive than TRUS for detecting ECE and SVI in organ-confined prostate cancer. TRUS had a relatively high specificity for ECE and SVI, and was better than eMRI in this regard. CONCLUSION: Whereas MRI tended to over-stage, TRUS under-staged prostate cancer. This series shows the current limited value of TRUS and eMRI for planning treatment in patients with clinically localized prostate cancer. Treatment decisions should not be altered based on TRUS or eMRI findings alone.

Aged↗
PubMed2001

Diagnosis and monitoring of urological tumors using positron emission tomography.

The purpose of this article was to critically review the diagnostic value of positron emission tomography (PET) in urological oncology. Urinary tract tumor assessment is hampered by the renal elimination of (18)F-fluorodeoxyglucose (FDG), the most commonly used PET radiopharmaceutical. PET imaging offers no significant benefits over conventional imaging modalities for renal cell and bladder carcinomas. As a result of the low metabolic activity of prostate cancer, PET does not differentiate adequately between adenoma and carcinoma, nor detect local recurrence after radical prostatectomy with sufficient sensitivity. However, lymph node staging with FDG-PET, specifically in bladder cancer, has been shown to have a potential clinical benefit. Further studies are required to determine the clinical value of retroperitoneal lymph node staging and recurrent disease detection in germ cell tumors. Finally, encouraging early results exist for the use of serial PET measurements to predict and assess therapy response to chemotherapy which may also be valuable in urological oncology.

Carcinoma, Renal Cell↗
PubMed2001

Giant malignant mesenchymoma of the spermatic cord with bidirectional differentiation.

BACKGROUND: Spermatic cord neoplasms are a rare tumor entity and, moreover, of benign behavior. Malignant tumors of the spermatic cord are mostly of mesenchymal origin. We present the unusual case of a giant malignant mesenchymoma of the spermatic cord with bidirectional differentiation into a liposarcoma and a leiomyosarcoma. CASE REPORT: A 84-year-old male patient presented with a scrotal mass on the left side which was observed growing since 1 year and misdiagnosed as scrotal hernia or testicular hydrocele. Ultrasound and computed tomography demonstrated a solid tumor suggesting a spermatic cord tumor. The patient underwent hemiscrotectomy, and the histological examination of the 2,500-gram specimen revealed a malignant mesenchymoma originating from the spermatic cord with two distinct histopathological compartments of liposarcoma and leiomyosarcoma. Because an adjuvant therapy protocol is of questionable effect and because of the patient's age no further therapy was applied. The patient was closely followed and is now, 5 years after surgery, still free of disease. CONCLUSION: Even in older patients, scrotal masses should be considered malignant tumors as long as no benign diagnosis has been proven. Although malignant mesenchymomas are rare tumors with poor prognosis, in selected cases even large tumor masses, as presented, can be cured by surgery.

Aged↗
PubMed2001

Coagulating intermittent cutting. Improved high-frequency surgery in transurethral prostatectomy.

OBJECTIVES: Transurethral prostatectomy (TURP) is the gold standard in surgical therapy of symptomatic bladder outlet obstruction. TURP is characterised by immediate treatment success, due to the removal of obstruction combined with a long-lasting improvement of symptoms and voiding parameters. In spite of good long-term results of TURP, intraoperative blood loss produces morbidity. We investigated a blood-sparing cut using a new high-frequency technology. METHODS: (1) A standard high frequency generator was extended in its function by additional electronics. (2) The possibility of a blood-sparing cut using 'coagulating intermittent cutting' (CIC cocut BMP) was quantified ex vivo using a blood-perfused porcine kidney. Four cuts next to each other were performed through the parenchyma using a standard resectoscope with a standard loop. This was done with a commercially available generator and CIC cocut BMP. The blood loss was determined semiqantitatively. RESULTS: (1) In a first step 'coagulating cutting' with coagulating and cutting periods (10/94-- 08/96) was developed. During each cut, phases with predominant cutting effect alternate with coagulating phases of defined duration. As a disadvantage, operation time increased due to lower cutting speed. In a second step cutting combined with coagulation effect with high voltage pulses -- 'coagulating intermittent cutting' (08/96--06/97) -- was developed. In this technique, the output signal consists of a pulse-modulated sinusoidal voltage with high amplitudes. But gas bubbles impaired vision. This finally resulted in the 'coagulating intermittent cutting' with constant voltage pulses and control of pulse intervals (CIC cocut BMP, since 07/97 up to now). (2) Comparing the function of the high-frequency generators in vitro, the Wilcoxon test for paired samples revealed a significant reduction of the observed bleeding with the CIC cocut BMP (p = 0.002). CONCLUSIONS: 'Coagulating intermittent cutting' improves the gold standard of TURP with reduced blood loss. The procedure is feasible with a standard resection equipment. The already trained surgeon has no further learning cure, and teaching of classical TURP is maintained.

Animals↗
PubMed2001

Do alpha-blockers prevent the occurrence of acute urinary retention?

Acute urinary retention (AUR) is a common complication of benign prostatic hyperplasia (BPH) and the incidence varies widely from 0.4 to 25% per year in men seen in urology practices. It has been estimated that AUR is the indication for surgery in around 25-30% of patients undergoing transurethral resection of the prostate (TURP) and that emergency TURP for AUR is associated with greater morbidity than elective TURP. Risk factors for AUR include lower urinary tract symptoms (LUTS), depressed peak urinary flow rate, enlarged prostate, high postvoid residual (PVR) urine and old age. Alfuzosin has been shown to significantly increase maximum flow rate and relieve bladder outlet obstruction, resulting in a reduction in PVR urine. A pooled analysis of 11 placebo-controlled studies involving 1,470 patients with LUTS suggestive of BPH indicates that significantly greater improvements were observed in patients treated with alfuzosin than with placebo. A 6-month placebo controlled study of 518 patients reported a 0.4% incidence of AUR in the alfuzosin group compared with a 2.4% incidence with placebo (p = 0.04). These positive effects on PVR could be related to the reduction in incidence of AUR seen in alfuzosin-treated patients.

Acute Disease↗
PubMed2001

Adrenal sparing surgery during radical nephrectomy in patients with renal cell cancer: a new algorithm.

PURPOSE: Ipsilateral adrenalectomy is usually performed during radical nephrectomy because of renal cell cancer. Because renal tumors are detected more often in the earlier stages due to widespread use of ultrasound and computerized tomography, we define a subset of patients who would be eligible for adrenal sparing surgery. In a retrospective analysis we evaluated whether parameters obtained preoperatively are able to predict adrenal metastasis. MATERIALS AND METHODS: A total of 866 consecutive patients who underwent nephrectomy and ipsilateral adrenalectomy from 1983 to 1999 were evaluated. Preoperative parameters, including tumor size, location, clinical stage, number of tumors, and patient age and sex, were retrospectively compared with the histological results. Univariate and multivariate analyses were performed. RESULTS: A total of 27 (3.1%) adrenal metastases were noted in the 866 patients, and 63% were on the left side and 37% on the right side. Mean tumor size was 10 cm. with versus 6 cm. without adrenal involvement. Of the 27 patients 21 had multiple metastases at diagnosis and only 6 (0.7% of all 866) presented with solitary ipsilateral adrenal metastasis. Univariate and multivariate analyses revealed tumor size and M stage as best preoperative predictors of adrenal involvement. CONCLUSIONS: Adrenal sparing surgery is possible, and we suggest a new algorithm. If maximum tumor size measured by computerized tomography is less than 8 cm. and staging examination does not show organ or lymph node metastases, adrenalectomy is not necessary because of oncological reasons. This algorithm has to be validated by a prospective analysis.

Adolescent↗
PubMed2001

Coagulating intermittent cutting: improved high-frequency surgery in transurethral prostatectomy.

PURPOSE: Despite the good long-term results of transurethral resection of the prostate (TURP), intraoperative blood loss and TUR syndrome produce morbidity. Thus, TURP is still considered invasive therapy. Many minor invasive alternative treatment modalities have been developed in recent years. MATERIAL AND METHODS: To minimize the risk of bleeding, we have improved on the high-frequency technology. The output signals of commercially available high-frequency generators were modulated such that each cut results in an efficient coagulation zone in the tissue with excellent cutting quality. RESULTS: Laboratory and in vitro studies using porcine kidneys as well as clinical trials showed good cutting characteristics accompanied by a significant reduction of bleeding. As a result, blood transfusions were less necessary, TUR syndrome occurred less often, the indwelling catheter could be removed earlier in the postoperative period, and hospitalization time was reduced. CONCLUSIONS: We believe that this improved high-frequency technology, termed coagulating intermittent cutting, results in blood-sparing tissue resection and reduction of morbidity.

Animals↗
PubMed2000

New ultradeformable drug carriers for potential transdermal application of interleukin-2 and interferon-alpha: theoretic and practical aspects.

Transfersomes (TFs) are highly deformable hydrophilic lipid vesicles that are able to penetrate the skin barrier spontaneously because of their characteristics. Transfersomes are able to transport noninvasively low- and high-molecular-weight molecules into the body. We describe the formulation and several biologic characteristics of interleukin-2 (IL-2)- and interferon-alpha (IFNalpha )-containing TFs. TFs contain natural phosphatidylcholine and sodium cholate. Recombinant human IL-2 and human hybrid IFNalpha were added to TFs and incubated for 24 hours at 4 degrees C. Immunotransfersomes were isolated from free IL-2 and IFNalpha by filtration (Centrisart, Sartorius). The biologic activity of immunotransfersomes was measured by a cytotoxic lymphoid line assay for IL-2 and by an A549-encephalomyocarditis virus assay for IFN; concentrations of proteins were determined by the enzyme-linked immunosorbent assay (ELISA). It was possible to incorporate a large amount of IL-2 and IFN in TFs (75-80%), and the incorporated IL-2, and IFN were biologically active. The increased lipid/protein ratio (90.9/1.0) led to a growing probability of association. We were thus able to show that IL-2 and IFN are trapped by transfersomes in a biologically active form and in sufficient concentrations for immunotherapy. In upcoming experiments these IL-2- and IFN-containing TFs will be used for a transdermal approach in the murine RENCA cell line model.

Administration, Cutaneous↗