C. van der Horst

Motor Cortical Representation of the Pelvic Floor Muscles

PURPOSE Pelvic floor muscle training involves rhythmical voluntary contractions of the external urethral sphincter and ancillary pelvic floor muscles. The representation of these muscles in the motor cortex has not been located precisely and unambiguously. We used functional magnetic resonance imaging to determine brain activity during slow and fast pelvic floor contractions. MATERIALS AND METHODS Cerebral responses were recorded in 17 healthy male volunteers, 21 to 47 years old, with normal bladder control. Functional magnetic resonance imaging was performed during metronome paced slow (0.25 Hertz) and fast (0.7 Hertz) contractions of the pelvic floor that mimicked the interruption of voiding. To study the somatotopy of the cortical representations, flexion-extension movements of the right toes were performed as a control task. RESULTS Functional magnetic resonance imaging during pelvic floor contractions detected activity of the supplementary motor area in the medial wall and of the midcingulate cortex, insula, posterior parietal cortex, putamen, thalamus, cerebellar vermis and upper ventral pons. There were no significant differences in activation between slow and fast contractions. Toe movements involved significantly stronger activity of the paracentral lobule (ie the medial primary motor cortex) than did the pelvic floor contractions. Otherwise the areas active during pelvic floor and leg muscle contractions overlapped considerably. CONCLUSIONS The motor cortical representation of pelvic floor muscles is located mostly in the supplementary motor area. It extends further ventrally and anteriorly than the representation of distal leg muscles.

Ätiologie und Pathophysiologie der Belastungsinkontinenz beim Mann

ZusammenfassungDie Belastungsinkontinenz ist eine seltene Erkrankung des Mannes. Mit einer durch die verbesserte Diagnostik der Prostataerkrankungen steigenden Anzahl von durchgeführten Operationen an der Prostata kommt es innerhalb der letzten Jahrzehnte zu einem konsekutiven Anstieg der von einer Belastungsinkontinenz betroffenen Männer. Als die vom Patienten – als auch vom Operateur – am meisten gefürchtete operationsbedingte Nebenwirkung ist die Inkontinenz einer der wichtigsten Faktoren in der Therapie der betroffenen Patienten. Eine eingeschränkte Kontinenzleistung bedeutet eine nicht unerhebliche Einschränkung der Lebensqualität der betroffenen Männer und deren Partner.Wenig bekannt ist über die pathophysiologischen Ursachen einer iatrogen verursachten Belastungsinkontinenz, von der vermutlich eher ältere als junge Männer betroffen sind. Die heutigen Kenntnisse stützen sich auf einige wenige klinisch experimentelle Studien.Neben der direkten myogenen oder neuronalen Schädigung des Schließmuskels scheinen eine nicht ausreichende Länge der funktionellen Urethra und eine gestörte Blasenfunktion wichtige Ursachen für das Auftreten einer postoperativen Inkontinenz zu sein. Zur Verbesserung der postoperativen Kontinenz nach radikaler Prostatektomie wurden verschiedene operative Modifikationen eingeführt. Der Erhalt des Blasenhalses, Schonung der puboprostatischen Bänder und der Gefäßnervenbündel sowie das Belassen der Samenblasenspitzen scheinen einen positiven Effekt auf die postoperative Kontinenzleistung zu haben.AbstractStress urinary incontinence is rare in men. Despite the improvements in diagnostic approaches to prostate diseases and surgical interventions on the prostate, stress incontinence has tended to increase in recent decades. The most frightening operative complication for both the patient and the surgeon is incontinence, which is one of the important factors in the treatment of the affected patients. The limited degree of continence considerably lowers the quality of life for the affected men and their partners.There is little information available about the pathophysiology of iatrogenic stress incontinence, which more likely affects older men rather than young men. The available information is based on a few experimental studies.Besides the direct damage to the muscular or neurological component of the external sphincter, insufficient length of the functional urethra and impaired bladder function seem to play an important role in the genesis of postoperative incontinence. In order to improve the postoperative continence status after radical prostatectomy a number of different operative modifications have been introduced. Preservation of the bladder neck, puboprostatic ligaments, and the neurovascular bundle as well as leaving the tips of the seminal vesicles seem to have a positive impact on the degree of postoperative continence.

Impact of Electrostimulation of Neurovascular Bundles and Pudendal Nerves on the Membranous Urethra in Male Rabbits

PURPOSE The pathophysiology of post-prostatectomy incontinence is supposed to be multifactorial. The impact of the neurovascular bundles on sphincter function is still under debate. We clarified the impact of cavernous nerves function on the MU. We compared MU pressure responses in male rabbits following electrophysiological stimulation trials on the neurovascular bundles vs pudendal nerve stimulation. MATERIALS AND METHODS Six male Chinchilla Bastard rabbits were included in this study. Pudendal and cavernous nerve branches were exposed bilaterally in all animals. Randomized electrostimulation of pudendal nerve fibers and the cavernous nerves, as confirmed by erection,) were done using a biphasic signal form of 0.3 mA for 200 microseconds. Stimulation frequency was changed in a randomized pattern from 10 to 40 Hz. Changes in MU pressure were measured urodynamically via a transurethral microtip catheter placed in the MU. Stimulation responses of the 2 nerve structures were compared. RESULTS Mean baseline pressure in the MU without stimulation was 23 cm H(2)O (range 20 to 25) in all animals. During unilateral pudendal stimulation the mean pressure response increased highly significantly to 33, 43, 59 and 60 cm H(2)O at 10, 20, 30 and 40 Hz, respectively (p <0.005). In contrast, compared to baseline pressure cavernous nerve stimulation did not result in any significant changes in proximal urethral pressure (mean 23 cm H(2)O, range 20 to 25, p >0.05). CONCLUSIONS Our results confirm the primacy of the pudendal nerve in the external urethral sphincter innervation. In contrast, stimulation of the cavernous nerves did not produce any pressure changes in the MU. These results confirm that the neurovascular bundles have no functional impact on the MU.

Erektile Dysfunktion nach radikaler Prostatektomie

BACKGROUND Postoperative erectile dysfunction (ED) is one of the potential after-effects of radical prostatectomy. The aim of this study was to learn which caregivers inform the patients prior to the intervention about the risk of ED, which individuals the patients discuss this issue with, and whether the patients preoperatively consider use of a PDE5 inhibitor for proerectile therapy after the operation. METHODS Using the IIEF-5 questionnaire, the preoperative erectile function of 110 patients was evaluated after the hospital admission interview. The patients were asked who had informed them about the risk of postoperative ED. They were also asked in whom they had confided to discuss this issue and whether they were prepared to undergo postoperative proerectile therapy with a PDE5 inhibitor. The patients were subsequently assigned to one of two groups: group I, consisting of those with a preoperative IIEF score > or = 21, or group II, those with a preoperative IIEF score <21. RESULTS The answers given by groups I and II did not differ significantly. The median patient age was the same, 68, in both groups. In addition to being informed about postoperative ED by the hospital doctor on admission (100%), the patients were informed about this by the following individuals (results for group II in parentheses): board-certified urologist, 81.8% (74%); general practitioner (GP), 27.3%; partner, 12.1% (11.7%); self-help groups, 0% (2.6%); and friends, 3% (6.5%). Patients also discussed the risk of postoperative ED with the following individuals (results for group II in parentheses): local urologist, 66.7% (63.4%); partner, 45.5% (42.9%); hospital doctor, 39.4% (42.9%); GP, 21.2% (23.4%); friends, 9.1% (14.3); or no one, 3% (5.2%). Regarding whether patients were willing to undergo postoperative therapy using a PDE5 inhibitor, 36.4% in group I and 32.5% in group II said yes, 12.1% in group I and 11.7% in group II said no, and 51.5% in group I and 55.8% in group II were undecided. CONCLUSION Irrespective of the patients erectile status, the hospital doctor and the local urologist informed the patients about the risk of postoperative ED. Satisfactory information delivered by at least two people occurred in over 70% of all cases. The most frequent confidant of the patient for discussing this issue was his local urologist. Fewer than 50% of the patients discussed this topic with their partners. Possible reasons for underestimating the importance of sexual function could be the frequent taboo status of sexuality as a discussion topic in relationships, as well as preoperative distress. These circumstances should be taken into account by offering sufficient information, including that on the availability of postoperative proerectile therapy, for both the patient and his partner as early as possible, i.e., at the stage of choosing a treatment option.

Die extendierte Sentinel-Lymphadenektomie im Rahmen der radikalen Prostatektomie?

Extended lymph node dissection during radical prostatectomy for prostate cancer remains a disputed area. Sentinel lymph scans help identify the first lymph node stages in the lymph drainage of the prostate. This study was designed to investigate the detection rate of lymph node metastasis by extended lymph node dissection and sentinel lymph node scanning in patients undergoing radical retropubic prostatectomy (RRP) for localized prostate cancer. In this study at our department from 2005 to 2006, a total of 108 patients with localized prostate carcinoma were treated with radical prostatectomy including extended lymph node dissection. A sentinel lymph node scan with 160 MBq of technetium-99m-Nanocoll (Tc) was performed 1 day before surgery. A C-Trak gamma probe (AEA Technologies, Morgan Hills, CA, USA) was used intraoperatively to detect the sentinel lymph nodes. Scan findings were correlated with tumor stage, Gleason score, prostate-specific antigen (PSA) level, and histological lymph node status. Scans revealed sentinel lymph nodes on the film 2 h after Tc administration in 98 of 108 patients (91%). Histologically proven lymph node metastases were detected in 15 of those 98 patients (15%) with a positive sentinel scan. Those 15 patients had a PSA level greater than 10 ng/ml or a Gleason score greater than 6 and at least a pT2 tumor. Specifically, six patients had a pT2 tumor, and nine patients had a pT3 tumor. Of patients placed in a risk group defined as PSA above 10 ng/ml or Gleason score greater than 6, 15 out of 50 patients (30%) had sentinel positive lymph nodes with metastasis. These data suggest that extended sentinel lymph node dissection helps identify lymph node metastasis in patients with PSA above 10 ng/ml or a Gleason score above 6 in 30% of cases. Further studies will show whether these numbers will hold true in patients undergoing radical prostatectomy for prostate cancer.

Funktionelle Ergebnisse nach temporärer Dauerableitung der hypokontraktilen Blase

BACKGROUND Impaired bladder emptying is a common problem in older people and a challenging task in treatment. Conservative and medical treatment options have shown beneficial effects on micturition; however, in a substantial number of patients the effectiveness of these therapies is disappointing. In the end the decompensated bladder needs indwelling catheterisation. To study the effects on the detrusor function, we analysed the urodynamic data of 31 patients during long-term bladder drainage retrospectively. PATIENTS AND METHODS All 17 female and 14 male patients showed impaired detrusor contractility, enlarged bladder capacity, decreased sensitivity and a high post-void residual urine volume (PVR). After exclusion of an acute pathology, the patients were treated continuously with a suprapubic catheter for an average of 13.1 weeks. By urodynamic measurements before and after the drainage period, we analysed the filling parameters, pressure-flow patterns, PVR and detrusor contractility. RESULTS At the end of the drainage period, significant changes in the detrusor function were obvious. Compared with the pre-treatment situation, the bladder volume at first desire to void decreased from 306.92 ml to 281.7 ml and the maximum bladder capacity from 691.8 ml to 496.8 ml, respectively. The compliance of the detrusor muscle diminished in the same period of time from 65.6 ml/cmH2O to 51.8 ml/cmH2O. The PVR dropped by 227.2 ml in average. The maximum flow rate was 9.4 ml/s, and the maximum detrusor pressure increased slightly up to 23.6 cmH2O. CONCLUSION The continuous drainage of the bladder results in significant changes in the motoric as well as sensoric detrusor function. The reduced bladder capacity and the decreased PVR might be indications of a regenerating process of the detrusor. The long-term drainage of the bladder shows beneficial and therefore therapeutic effects. It still remains to be investigated on a functional as well as structural basis to what extent age, gender and pathogenesis influences the rehabilitation of the detrusor.

Erektile Dysfunktion nach radikaler Prostatektomie@@@Erectile dysfunction after radical prostatectomy: Aufklärung, Ansprechpartner, postoperative proerektile Therapie@@@Patient information, contact persons, postoperative proerectile therapy

BACKGROUND Postoperative erectile dysfunction (ED) is one of the potential after-effects of radical prostatectomy. The aim of this study was to learn which caregivers inform the patients prior to the intervention about the risk of ED, which individuals the patients discuss this issue with, and whether the patients preoperatively consider use of a PDE5 inhibitor for proerectile therapy after the operation. METHODS Using the IIEF-5 questionnaire, the preoperative erectile function of 110 patients was evaluated after the hospital admission interview. The patients were asked who had informed them about the risk of postoperative ED. They were also asked in whom they had confided to discuss this issue and whether they were prepared to undergo postoperative proerectile therapy with a PDE5 inhibitor. The patients were subsequently assigned to one of two groups: group I, consisting of those with a preoperative IIEF score > or = 21, or group II, those with a preoperative IIEF score <21. RESULTS The answers given by groups I and II did not differ significantly. The median patient age was the same, 68, in both groups. In addition to being informed about postoperative ED by the hospital doctor on admission (100%), the patients were informed about this by the following individuals (results for group II in parentheses): board-certified urologist, 81.8% (74%); general practitioner (GP), 27.3%; partner, 12.1% (11.7%); self-help groups, 0% (2.6%); and friends, 3% (6.5%). Patients also discussed the risk of postoperative ED with the following individuals (results for group II in parentheses): local urologist, 66.7% (63.4%); partner, 45.5% (42.9%); hospital doctor, 39.4% (42.9%); GP, 21.2% (23.4%); friends, 9.1% (14.3); or no one, 3% (5.2%). Regarding whether patients were willing to undergo postoperative therapy using a PDE5 inhibitor, 36.4% in group I and 32.5% in group II said yes, 12.1% in group I and 11.7% in group II said no, and 51.5% in group I and 55.8% in group II were undecided. CONCLUSION Irrespective of the patients erectile status, the hospital doctor and the local urologist informed the patients about the risk of postoperative ED. Satisfactory information delivered by at least two people occurred in over 70% of all cases. The most frequent confidant of the patient for discussing this issue was his local urologist. Fewer than 50% of the patients discussed this topic with their partners. Possible reasons for underestimating the importance of sexual function could be the frequent taboo status of sexuality as a discussion topic in relationships, as well as preoperative distress. These circumstances should be taken into account by offering sufficient information, including that on the availability of postoperative proerectile therapy, for both the patient and his partner as early as possible, i.e., at the stage of choosing a treatment option.

Die extendierte Sentinel-Lymphadenektomie im Rahmen der radikalen Prostatektomie?@@@Extended sentinel lymph node dissection in radical prostatectomy for prostate cancer: Untersuchungen im Kieler Risikokollektiv@@@A study in the Kiel risk population

Extended lymph node dissection during radical prostatectomy for prostate cancer remains a disputed area. Sentinel lymph scans help identify the first lymph node stages in the lymph drainage of the prostate. This study was designed to investigate the detection rate of lymph node metastasis by extended lymph node dissection and sentinel lymph node scanning in patients undergoing radical retropubic prostatectomy (RRP) for localized prostate cancer. In this study at our department from 2005 to 2006, a total of 108 patients with localized prostate carcinoma were treated with radical prostatectomy including extended lymph node dissection. A sentinel lymph node scan with 160 MBq of technetium-99m-Nanocoll (Tc) was performed 1 day before surgery. A C-Trak gamma probe (AEA Technologies, Morgan Hills, CA, USA) was used intraoperatively to detect the sentinel lymph nodes. Scan findings were correlated with tumor stage, Gleason score, prostate-specific antigen (PSA) level, and histological lymph node status. Scans revealed sentinel lymph nodes on the film 2 h after Tc administration in 98 of 108 patients (91%). Histologically proven lymph node metastases were detected in 15 of those 98 patients (15%) with a positive sentinel scan. Those 15 patients had a PSA level greater than 10 ng/ml or a Gleason score greater than 6 and at least a pT2 tumor. Specifically, six patients had a pT2 tumor, and nine patients had a pT3 tumor. Of patients placed in a risk group defined as PSA above 10 ng/ml or Gleason score greater than 6, 15 out of 50 patients (30%) had sentinel positive lymph nodes with metastasis. These data suggest that extended sentinel lymph node dissection helps identify lymph node metastasis in patients with PSA above 10 ng/ml or a Gleason score above 6 in 30% of cases. Further studies will show whether these numbers will hold true in patients undergoing radical prostatectomy for prostate cancer.

Funktionelle Ergebnisse nach temporärer Dauerableitung der hypokontraktilen Blase@@@Functional results after temporary continuous drainage of the hypocontractile bladder: Zur Rehabilitationsfähigkeit des Detrusors@@@The potential rehabilitation of the detrusor

BACKGROUND Impaired bladder emptying is a common problem in older people and a challenging task in treatment. Conservative and medical treatment options have shown beneficial effects on micturition; however, in a substantial number of patients the effectiveness of these therapies is disappointing. In the end the decompensated bladder needs indwelling catheterisation. To study the effects on the detrusor function, we analysed the urodynamic data of 31 patients during long-term bladder drainage retrospectively. PATIENTS AND METHODS All 17 female and 14 male patients showed impaired detrusor contractility, enlarged bladder capacity, decreased sensitivity and a high post-void residual urine volume (PVR). After exclusion of an acute pathology, the patients were treated continuously with a suprapubic catheter for an average of 13.1 weeks. By urodynamic measurements before and after the drainage period, we analysed the filling parameters, pressure-flow patterns, PVR and detrusor contractility. RESULTS At the end of the drainage period, significant changes in the detrusor function were obvious. Compared with the pre-treatment situation, the bladder volume at first desire to void decreased from 306.92 ml to 281.7 ml and the maximum bladder capacity from 691.8 ml to 496.8 ml, respectively. The compliance of the detrusor muscle diminished in the same period of time from 65.6 ml/cmH2O to 51.8 ml/cmH2O. The PVR dropped by 227.2 ml in average. The maximum flow rate was 9.4 ml/s, and the maximum detrusor pressure increased slightly up to 23.6 cmH2O. CONCLUSION The continuous drainage of the bladder results in significant changes in the motoric as well as sensoric detrusor function. The reduced bladder capacity and the decreased PVR might be indications of a regenerating process of the detrusor. The long-term drainage of the bladder shows beneficial and therefore therapeutic effects. It still remains to be investigated on a functional as well as structural basis to what extent age, gender and pathogenesis influences the rehabilitation of the detrusor.