Helmut H. Knispel
Free University of Berlin
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Featured researches published by Helmut H. Knispel.
European Urology | 2014
Alexander Bachmann; Andrea Tubaro; Neil J. Barber; Frank d’Ancona; Gordon Muir; U. Witzsch; Marc-Oliver Grimm; Joan Benejam; Jens-Uwe Stolzenburg; Antony C.P. Riddick; Sascha Pahernik; Herman Roelink; Filip Ameye; C. Saussine; Franck Bruyère; Wolfgang Loidl; Tim Larner; Nirjan-Kumar Gogoi; Richard G. Hindley; Rolf Muschter; Andrew Thorpe; Nitin Shrotri; Stuart Graham; Moritz Hamann; Kurt Miller; Martin Schostak; Carlos Capitán; Helmut H. Knispel; J. Andrew Thomas
BACKGROUND The comparative outcome with GreenLight (GL) photoselective vaporisation of the prostate and transurethral resection of the prostate (TURP) in men with lower urinary tract symptoms due to benign prostatic obstruction (BPO) has been questioned. OBJECTIVE The primary objective of the GOLIATH study was to evaluate the noninferiority of 180-W GL XPS (XPS) to TURP for International Prostate Symptom Score (IPSS) and maximum flow rate (Qmax) at 6 mo and the proportion of patients who were complication free. DESIGN, SETTING, AND PARTICIPANTS Prospective randomised controlled trial at 29 centres in 9 European countries involving 281 patients with BPO. INTERVENTION 180-W GL XPS system or TURP. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Measurements used were IPSS, Qmax, prostate volume (PV), postvoid residual (PVR) and complications, perioperative parameters, and reintervention rates. Noninferiority was evaluated using one-sided tests at the 2.5% level of significance. The statistical significance of other comparisons was assessed at the (two-sided) 5% level. RESULTS AND LIMITATIONS The study demonstrated the noninferiority of XPS to TURP for IPSS, Qmax, and complication-free proportion. PV and PVR were comparable between groups. Time until stable health status, length of catheterisation, and length of hospital stay were superior with XPS (p<0.001). Early reintervention rate within 30 d was three times higher after TURP (p=0.025); however, the overall postoperative reintervention rates were not significantly different between treatment arms. A limitation was the short follow-up. CONCLUSIONS XPS was shown to be noninferior (comparable) to TURP in terms of IPSS, Qmax, and proportion of patients free of complications. XPS results in a lower rate of early reinterventions but has a similar rate after 6 mo. TRIAL REGISTRATION ClinicalTrials.gov, identifier NCT01218672.
The Journal of Urology | 1991
Helmut H. Knispel; Carsten Goessl; R. Beckmann
Externally applied acetylcholine (ACh) in human corpus cavernosum has been shown to cause endothelium-dependent smooth muscle relaxation. Changes in isometric tension in rabbit cavernous smooth muscle strips mounted in organ bath chambers were monitored in the presence of blocking agents. Nitric oxide (NO) is known as an endothelium-derived relaxation factor (EDRF). Addition of specific inhibitors of nitric oxide synthesis, such as L-n-monomethyl arginine (L-NMMA) at 5 x 10(-4) mol/l.. or L-n-nitro arginine (L-NOARG) at 2 x 10(-4) mol/l. to strips precontracted with phenylephrine (PE) at 3.16 x 10(-6) mol/l. led to significant increases in tension. In the presence of L-NMMA or L-NOARG, relaxing effects of ACh at 10(-8)-3.16 x 10(-5) mol/l. mediated by muscarinic receptors were almost completely abolished. These data indicate that rabbit cavernous smooth muscle is under the control of basal NO release. They constitute strong evidence that cholinergically induced endothelial formation of NO plays a crucial role in relaxing cavernous smooth muscle.
The Journal of Urology | 1997
Carsten Goessl; Helmut H. Knispel; Kurt Miller; R. Klän
PURPOSE We determined whether routine excretory urography (IVP) at initial diagnosis of bladder cancer is useful in screening the upper urinary tract for clinically inapparent urothelial tumors. MATERIALS AND METHODS IVPs and ultrasound findings of 314 patients with bladder cancer were reviewed retrospectively. RESULTS Only 1 silent upper urinary tract tumor was detected with IVP (0.3%), resulting in nephroureterectomy. IVP had no further therapeutic consequences except for destruction of an asymptomatic prevesical stone. IVP was followed by ureterorenoscopy in 5 patients with negative results. Upper urinary tract obstruction could be documented equally well by sonography in all cases. CONCLUSIONS Routine IVP at first diagnosis of bladder cancer is unnecessary.
Urological Research | 1992
Helmut H. Knispel; Carsten Goessl; R. Beckmann
SummaryWe investigated in vitro the relaxant effect of exogenous acetylcholine (ACh) and electric-field stimulation (EFS) on rabbit and human corpus cavernosum smooth muscle strips (CC) precontracted with phenylephrine. The effects of EFS and ACh were monitored alone, after muscarinic receptor blockade and after inhibition of nitric oxide (NO) formation with l-N-nitroarginine (l-NOARG). In rabbit und human CC, both atropine and l-NOARG abolished the relaxant effects of ACh. The relaxant effects of EFS, however, were only slightly reduced by atropine to 97.5±17.5% in human CC and to 89.0±6.1% in rabbit CC. l-NOARG further reduced the EFS effects to 0.8±1.7% in human CC and to 16.2±8.7% in rabbit CC. In strips obtained from impotent patients with diabetes mellitus, the relaxant effects appeared to be significantly less than in strips from nondiabetic impotent men. Tetrodotoxin blocked the relaxant EFS effects in human and rabbit strips completely. The data indicate the important role of NO in cholinergically induced relaxation of cavernous smooth muscle in rabbits and humans. Our findings support the idea of NO as the nonadrenergic noncholinergic neurotransmitter in penile erection in both species. Rabbit erectile tissue might serve as an in vitro animal model for further investigation.
The Journal of Urology | 2015
Alexander Bachmann; Andrea Tubaro; Neil J. Barber; Frank d’Ancona; Gordon Muir; U. Witzsch; Marc-Oliver Grimm; Joan Benejam; Jens-Uwe Stolzenburg; Antony C.P. Riddick; Sascha Pahernik; Herman Roelink; Filip Ameye; C. Saussine; Franck Bruyère; Wolfgang Loidl; Tim Larner; Nirjan-Kumar Gogoi; Richard G. Hindley; Rolf Muschter; Andrew Thorpe; Nitin Shrotri; Stuart L. Graham; Moritz Hamann; Kurt Miller; Martin Schostak; Carlos Capitán; Helmut H. Knispel; J. Andrew Thomas
PURPOSE We present the 1-year results of the GOLIATH prospective randomized controlled trial comparing transurethral resection of the prostate to GreenLight XPS for the treatment of men with nonneurogenic lower urinary tract symptoms due to prostate enlargement. The updated results at 1 year show that transurethral resection of the prostate and GreenLight XPS remain equivalent, and confirm the therapeutic durability of both procedures. We also report 1-year followup data from several functional questionnaires (OABq-SF, ICIQ-SF and IIEF-5) and objective assessments. MATERIALS AND METHODS A total of 291 patients were enrolled at 29 sites in 9 European countries. Patients were randomized 1:1 to undergo GreenLight XPS or transurethral resection of the prostate. The trial was designed to evaluate the hypothesis that GreenLight XPS is noninferior to transurethral resection of the prostate on the International Prostate Symptom Score at 6 months. Several objective parameters were assessed, including maximum urinary flow rate, post-void residual urine volume, prostate volume and prostate specific antigen, in addition to functional questionnaires and adverse events at each followup. RESULTS Of the 291 enrolled patients 281 were randomized and 269 received treatment. Noninferiority of GreenLight XPS was maintained at 12 months. Maximum urinary flow rate, post-void residual urine volume, prostate volume and prostate specific antigen were not statistically different between the treatment arms at 12 months. The complication-free rate at 1 year was 84.6% after GreenLight XPS vs 80.5% after transurethral resection of the prostate. At 12 months 4 patients treated with GreenLight XPS and 4 who underwent transurethral resection of the prostate had unresolved urinary incontinence. CONCLUSIONS Followup at 1 year demonstrated that photoselective vaporization of the prostate produced efficacy outcomes similar to those of transurethral resection of the prostate. The complication-free rates and overall reintervention rates were comparable between the treatment groups.
European Urology | 2009
Andreas Böhle; Herbert Leyh; Christian Frei; Michael Kühn; Reinhold Tschada; Tobias Pottek; Walter Wagner; Helmut H. Knispel; Wolfgang von Pokrzywnitzki; Ferruh Zorlu; Karin Helsberg; Birgit Lübben; Victoria Soldatenkova; Clemens Stoffregen; Hartwig Büttner
BACKGROUND Recurrence prophylaxis with intravesical gemcitabine (GEM) was effective and safe in patients with non-muscle-invasive bladder cancer (NMIBC); efficacy as single-shot instillation remains to be proved. OBJECTIVE To compare the efficacy of a single GEM instillation versus placebo (PBO) immediately after transurethral resection (TUR) of tumour in patients with histologically confirmed NMIBC (pTa/pT1,G1-3). DESIGN, SETTING, AND PARTICIPANTS This was a double-blind, randomised, PBO-controlled study in patients with clinical evidence of primary or recurrent NMIBC (Ta/T1,G1-3). Of 355 patients randomised at 24 urologic centres, 328 underwent TUR and received instillation (92.4%; GEM/PBO: 166/162). In case of nonmalignancy, carcinoma in situ (CIS), > or = pT2 disease, or intraoperative complications, patients were discontinued. INTERVENTION We used a single, postoperative 30-40-min instillation of GEM (2000 mg/100 ml of saline) or PBO (100 ml of saline) followed by continuous bladder irrigation for > or = 20 h. A second TUR (no instillation) and adjuvant bacillus Calmette-Guérin (BCG) instillations were allowed. MEASUREMENTS Primary outcome was recurrence-free survival (RFS). Secondary outcomes included type of recurrence and adverse events. To detect a difference in RFS, 191 recurrences were required (80% power, log-rank-test, alpha = 0.050). RESULTS AND LIMITATIONS Two hundred forty-eight patients (69.9%, GEM, PBO: 124, 124) had histologically confirmed pTa/pT1 G1-3 Gx tumour and were eligible for efficacy (GEM: 76.6% male; median age: 65 yr; PBO: 83.1% male; median age: 67 yr). Treatment groups were balanced (pTa: 75.0%, 71.0%; G1-G2: 85.5%, 87.9%; recurrent tumour: 24.2%, 21.0%; BCG: 10.5%, 16.9%). After a median follow-up of 24 mo, there were only 94 recurrences and 11 deaths. The study was terminated early based on predefined decision criteria. RFS was high in both groups (12-mo RFS [95% confidence interval (CI)]: GEM: 77.7% [68.8-84.3]; PBO: 75.3% [66.3-82.3]). There was no significant group difference (hazard ratio [HR]: 0.946 [0.64-1.39], log-rank test, p=0.777). CONCLUSIONS In this study of NMIBC, the immediate single instillation of GEM 2000 mg/100 ml of saline after TUR was not superior to PBO in terms of RFS. Rigid continuous irrigation and improved TUR/cystoscopy techniques may have contributed to the high RFS in both groups.
European Urology | 2016
James Andrew Thomas; Andrea Tubaro; Neil J. Barber; Frank d’Ancona; Gordon Muir; U. Witzsch; Marc-Oliver Grimm; Joan Benejam; Jens-Uwe Stolzenburg; Antony C.P. Riddick; Sascha Pahernik; Herman Roelink; Filip Ameye; C. Saussine; Franck Bruyère; Wolfgang Loidl; Tim Larner; Nirjan-Kumar Gogoi; Richard G. Hindley; Rolf Muschter; Andrew Thorpe; Nitin Shrotri; Stuart L. Graham; Moritz Hamann; Kurt Miller; Martin Schostak; Carlos Capitán; Helmut H. Knispel; Alexander Bachmann
BACKGROUND The GOLIATH study is a 2-yr trial comparing transurethral resection of prostate (TURP) to photoselective vaporization with the GreenLight XPS Laser System (GL-XPS) for the treatment of benign prostatic obstruction (BPO). Noninferiority of GL-XPS to TURP was demonstrated based on a 6-mo follow-up from the study. OBJECTIVE To determine whether treatment effects observed at 6 mo between GL-XPS and TURP was maintained at the 2-yr follow-up. DESIGN, SETTING, AND PARTICIPANTS Prospective randomized controlled trial at 29 centers in nine European countries involving 281 patients with BPO. INTERVENTION Photoselective vaporization using the 180-W GreenLight GL-XPS or conventional (monopolar or bipolar) TURP. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The primary outcome was the International Prostate Symptom Score for which a margin of three was used to evaluate the noninferiority of GL-XPS. Secondary outcomes included Qmax, prostate volume, prostate specific antigen, Overactive Bladder Questionnaire Short Form, International Consultation on Incontinence Questionnaire Short Form, occurrence of surgical retreatment, and freedom from complications. RESULTS AND LIMITATIONS One hundred and thirty-six patients were treated using GL-XPS and 133 using TURP. Noninferiority of GL-XPS on International Prostate Symptom Score, Qmax, and freedom from complications was demonstrated at 6-mo and was sustained at 2-yr. The proportion of patients complication-free through 24-mo was 83.6% GL-XPS versus 78.9% TURP. Reductions in prostate volume and prostate specific antigen were similar in both arms and sustained over the course of the trial. Compared with the 1(st) yr of the study, very few adverse events or retreatments were reported in either arm. Treatment differences in the Overactive Bladder Questionnaire Short Form observed at 12-mo were not statistically significant at 24-mo. A limitation was that patients and treating physicians were not blinded to the therapy. CONCLUSIONS Twenty-four-mo follow-up data demonstrated that GL-XPS provides a durable surgical option for the treatment of BPO that exhibits efficacy and safety outcomes similar to TURP. PATIENT SUMMARY The long-term effectiveness and safety of GLP-XLS was similar to conventional TURP for the treatment of prostate enlargement.
Urology | 1998
Carsten Goessl; Helmut H. Knispel; U. Fiedler; B Härle; K Steffen-Wilke; Kurt Miller
OBJECTIVES To investigate the effects of oral oxybutynin chloride (OC) on standard urodynamic measures in children with myelomeningocele (MMC) and detrusor hyperreflexia. METHODS Forty-one MMC children with detrusor hyperreflexia (19 boys and 22 girls, aged 2 months to 15 years; mean 4.9 years) were evaluated urodynamically before and within 3 months after initiation of oral OC therapy (0.2 to 0.3 mg/kg/day). Therapy with oral OC was always combined with clean intermittent catheterization (CIC). RESULTS Oral OC treatment caused an increase in bladder capacity from 141 +/- 96 to 197 +/- 99 mL (+ 40%; P < 0.01), a decrease in detrusor pressure at maximal capacity from 45 +/- 32 to 28 +/- 23 cm H2O (-38%; P < 0.01), and an increase in detrusor compliance from 6.5 +/- 5.6 to 16.8 +/- 13.7 mL/cm H2O (+ 158%; P < 0.01). Improvement in urodynamic measures and continence were correlated. After a follow-up of at least 2 years, effective protection of renal function was achieved in 38 of the 41 children (93%) with conservative therapy alone. Adverse effects resulted in discontinuation of oral OC treatment in only 2 cases. CONCLUSIONS Treatment with oral OC and CIC is effective and safe in children with MMC and detrusor hyperreflexia and should be initiated early when indicated by urodynamic findings.
Urology | 1992
Helmut H. Knispel; Carsten Goessl; R. Beckmann
We investigated the relaxant effect of electric field stimulation (EFS) on rabbit cavernous smooth muscle strips in vitro precontracted by phenylephrine. Effects of EFS were monitored alone, and following muscarinic receptor blockade, and inhibition of nitric oxide (NO) formation by L-N-monomethylarginine (L-NMMA) or by L-N-nitroarginine (L-NOARG). Atropine only slightly reduced the relaxant effect of EFS to 89.0 +/- 6.1 percent. Additional application of L-NMMA further reduced the relaxant effect to 37.3 +/- 15.3 percent. Substitution of L-NOARG for L-NMMA led to a more pronounced inhibition of relaxant effects to 16.2 +/- 8.7 percent. The results indicate that neurogenically induced relaxation of rabbit cavernous smooth muscle is mediated mainly by NO formation and argue against a substantial role of relaxing peptidergic neurotransmitters, such as vasoactive intestinal polypeptide and calcitonin-gene-related peptide, in penile erection.
Urologia Internationalis | 1996
Helmut H. Knispel; R. Klän; Gerd Offermann; Kurt Miller
Some transplantation centers still suggest nephrectomy in patients with autosomal dominant polycystic kidney disease (ADPKD) before kidney transplantation at least in selected cases. We wanted to learn whether prior nephrectomy is beneficial. The outcome of kidney transplantation in 47 consecutive ADPKD patients without prior nephrectomy was compared with that in matched controls with respect to complications of ADPKD. Although ADPKD patients were older than controls (mean, 50.1 vs. 40.3 years), there was no statistically significant difference in 1- and 5-year allograft survival between ADPKD patients and controls: 76.6 and 68.0%, respectively, in ADPKD patients, and 83.9 and 56.3% in controls. After a mean follow-up of 66.5 months 3 patients with ADPKD had cyst infections and were managed with antibiotics. Two patients had episodes of hematuria; neither required invasive therapy. There was no renal malignancy and clinical sign of urolithiasis in any patient. No posttransplantation nephrectomy was required. With only few indications remaining, there is no rationale for routine pretransplantation nephrectomy in patients with ADPKD.