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Christoph Seif

Publications and source records attributed to Christoph Seif.

13 recordsLinked to original sources
PubMed2006

Subthalamic stimulation modulates cortical control of urinary bladder in Parkinson's disease.

Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective therapy for off-period motor symptoms and dyskinesias in advanced Parkinson's disease. Clinical studies have shown that STN-DBS also ameliorates urinary bladder function in Parkinson's disease patients by delaying the first desire to void and increasing bladder capacity. This study aimed at investigating the effect of STN-DBS on the neural mechanisms underlying cerebral bladder control. Using PET to measure changes in regional cerebral blood flow (rCBF), 11 patients with bilateral STN-DBS were studied during urodynamic bladder filling in STN-DBS ON and OFF condition. A filled bladder led to a significant increase of rCBF in the anterior cingulate cortex, which was further enhanced during STN-DBS OFF. A significant interaction between bladder state and STN-DBS was observed in lateral frontal cortex with increased rCBF when the bladder was filled during STN-DBS OFF. The data suggest that STN-DBS ameliorates bladder dysfunction and that this modulation may result from facilitated processing of afferent bladder information.

Adult↗
PubMed2006

Nocturnal tumescence: a parameter for postoperative erectile integrity after nerve sparing radical prostatectomy.

PURPOSE: The exact process and time required for rehabilitation of erectile function after nerve sparing prostatectomy remain unclear to date. Different theories of the pathophysiology of postoperative erectile dysfunction are currently being discussed. In a prospective study we performed recordings of nocturnal penile tumescence and rigidity during the acute phase after nerve sparing radical prostatectomy, ie in the first night after removal of the catheter, to assess the organic penile integrity. MATERIALS AND METHODS: In 27 patients with local prostate carcinoma who had been sexually active before the intervention, we performed unilateral or bilateral nerve sparing radical prostatectomy. Preoperative sexual function of all patients was evaluated by the International Index of Erectile Function-5 questionnaire. On the day of catheter removal (postoperative day 7 to 14) an NPTR recording was performed on the following night with an erectometer (RigiScan). RESULTS: All patients had a preoperative IIEF score greater than 18. After removal of the catheter 25 of 27 patients (93%) showed 1 to 5 nocturnal rigidity increases by greater than 70% for at least 10 minutes. In a control group of 4 patients who underwent radical prostatectomy without nerve sparing, no nocturnal erections were recorded. CONCLUSIONS: NPTR recording during the acute phase after nerve sparing radical prostatectomy showed residual erectile function as early as the first night after catheter removal. These results are significant for selecting adequate pharmacological treatment for optimal therapy and rehabilitation of satisfactory erections and sexual function. In cases of early nocturnal tumescence, application of a PDE5 inhibitor can support successive organ rehabilitation. However, if tumescence does not occur, penile injection therapy is recommended.

Aged↗
PubMed2005

Penile carcinoma (pT1 G2): surveillance or inguinal lymph node dissection?

BACKGROUND: Due to the low incidence of squamous cell penile cancer and lack of well-designed studies, controversies persist over the therapeutic approach in patients with pT1 G2 carcinoma. PATIENTS AND METHODS: Between 1992 and 2003, 16 patients with T1 squamous penile cancer were treated in our institution either by surveillance or by inguinal lymph node dissection (ILND). RESULTS: A total of 8 primary lesions were classified as pT1 G2 carcinoma with 4 tumors developing early or delayed inguinal metastatic disease. CONCLUSIONS: The natural behavior of pT1 G2 squamous penile carcinoma and its metastatic potential has been underestimated in recent literature. Since morbidity after early ILND has markedly decreased and its superiority over delayed ILND has been shown, we advocate the early modified inguinal lymph node dissection until strong prognostic factors for positive inguinal lymph nodes have been validated.

Adult↗
PubMed2004

Methylene blue staining for nerve-sparing operative procedures: an animal model.

OBJECTIVES: To evaluate methylene blue fiber staining as a method of nerve fiber identification in an animal model, because the maintenance of organ function after surgery depends on exact intraoperative identification of the relevant nerve fibers. METHODS: Brindley electrodes were implanted bilaterally at S3 for sacral anterior root stimulation in six minipigs. For reference, stimulation-induced detrusor contractions were recorded urodynamically. After exposure of the ureterovesical junction on both sides, a 2:8 methylene blue solution was applied to the right side; the left side remained untreated. Bilateral dissection of the ureter from the surrounding tissue for a distance of 4 cm proximal to the ureterovesical junction was performed. The methylene blue-stained nerve fibers on the right side were spared; no particular attention was paid to the nerves on the left. Again, sacral anterior root stimulation-induced detrusor contractions were monitored urodynamically on both sides. Then, the identified nerve fibers on the right were cut intentionally, and the detrusor pressure was recorded again under stimulation. Finally, the dissected nerve structures were evaluated histologically. RESULTS: The reference bladder pressures after unilateral stimulation on the left side before ureter dissection showed a mean detrusor pressure (Pdet) of 19 cm H2O. On the right side, the Pdet was 18 cm H2O. After preparation on both sides, a mean Pdet of 3 cm H2O was recorded after left side stimulation, and a Pdet of 17 cm H2O after right side stimulation. When the stained nerve fibers on the right side were cut, no bladder contractions could be induced. The histomorphology of the stained and dissected structures revealed multiple autonomous nerve fibers and small vessels in connective tissue. CONCLUSIONS: The identification of minute nerve bundles is a tedious and difficult task. The results from our animal model demonstrated that supravital staining of autonomous nerve fibers with methylene blue is a simple and reliable method of identification.

Animals↗
PubMed2004

Restoration of external urethral sphincter function after pudendal nerve end-to-end anastomosis in the male rabbit.

PURPOSE: In this study we rehabilitated external urethral sphincter function by pudendal nerve end-to-end anastomosis after experimental pudendal nerve axotomy in male rabbits. MATERIALS AND METHODS: A total of 17 animals were included in this study, including group 1-a control group of 5 (29.4%), group 2-6 (35.3%) and group 3-6 (35.3%). Animals from group 2 underwent bilateral axotomy and group 3 underwent pudendal nerve end-to-end anastomosis. In all groups we performed urodynamic investigations prior to axotomy, after axotomy or anastomosis, and 14, 42 and 90 days after axotomy or nerve anastomosis. RESULTS: In untreated group 1 control sphincter pressure was 28.5 cm H2O. In group 2 average urethral sphincter pressure was 5.6 cm H2O 14 days after axotomy with only a slight increase to 11.05 cm H2O by day 90. In group 3 external urethral pressure increased to 8.26 cm H2O after 14 days and to 21.32 cm H2O by postoperative day 90. CONCLUSIONS: External urethral sphincter deficiency after bilateral pudendal nerve axotomy demonstrates the primacy of the pudendal nerve in the innervation of the external urethral sphincter. We were able to rehabilitate external urethral sphincter function by performing pudendal nerve end-to-end anastomosis.

Anastomosis, Surgical↗
PubMed2003

The role of the carbachol test and concomitant diseases in patients with nonobstructive urinary retention undergoing sacral neuromodulation.

The aim of this study was to evaluate the percutaneous nerve evaluation (PNE) test success in patients with nonobstructive urinary retention. A total of 24 PNE tests were performed in patients with nonobstructive urinary retention and in 18 patients, a carbachol test was performed during urodynamics. The diagnosis relating to the acontractile detrusor was also assessed and compared to the outcome of the PNE test. The PNE test was successful in eight of 24 patients (33.3%) with the the highest success rate being observed in patients after hysterectomy (80%). It was successful in five of 12 patients with negative carbachol tests and in three of six patients with positive carbachol tests. We conclude that sacral neuromodulation is an effective treatment option in patients with nonobstructive urinary retention. PNE tests should be performed in all patients with therapy resistant nonobstructive urinary retention, because predictive factors do not exist.

Adult↗
PubMed2003

Risk of detrusor denervation in antireflux surgery demonstrated in a neurophysiological animal model.

PURPOSE: Earlier anatomical studies have shown a close connection between the ureterovesical junction and detrusor innervation. It prompted us to develop an animal model to demonstrate the risk of partial or complete impairment of this neuronal connection during antireflux surgery. MATERIALS AND METHODS: Six female Göttinger minipigs were anesthetized and laminectomized. After placement of the S3 sacral nerves into separate electrode compartments of a modified Brindley electrode the lower urinary tract was exposed by an abdominal midline incision. After bladder instillation with 150 ml NaCl 1 bilateral and 2 unilateral stimulations (left and right sides) were performed and intravesical pressure was recorded urodynamically. The left ureter was then prepared circularly in 3 steps 10, 5 and 1 cm, respectively, proximal to the ureterovesical junction. After each preparation step bilateral and unilateral stimulation was repeated. Results were recorded urodynamically and video documented. RESULTS: Bilateral stimulation before preparation of the left ureter led to a concentric detrusor contraction with an average maximum detrusor pressure of 51 cm H(2)O. Unilateral stimulation resulted in ipsilateralbound bladder tilting with an intravesical pressure of 18 and 19 cm H(2)O on the right and left sides, respectively. After preparation of the left ureter 10, 5 and 1 cm from the ureterovesical junction a maximum detrusor pressure of 17, 10 and 1 cm H(2)O was documented, respectively. While there was almost no stimulation response of the bladder after the last preparation step at 1 cm on the left ureter, the initial bladder pressure of 18 cm H(2)O could be reproduced under stimulation on the right side. CONCLUSIONS: Analogous to human cadaver studies, we were able to prove neurophysiologically strictly unilateral detrusor innervation, drawing from the pelvic plexus dorsomedial to the ureterovesical junction into the bladder. Preparation of this ureterovesical junction during antireflex surgery, coagulating measures in this area or the affixation of anchor sutures after a Vest suture involves the risk of unilateral or bilateral detrusor decentralization.

Animals↗
PubMed2003

The acute myotoxic effects of bupivacaine and ropivacaine after continuous peripheral nerve blockades.

UNLABELLED: Bupivacaine causes muscle damage. However, the myotoxic potency of ropivacaine is still unexplored. Therefore, we performed this study to compare the effects of bupivacaine and ropivacaine on skeletal muscle tissue in equipotent concentrations. Femoral nerve catheters were inserted into anesthetized minipigs, and 20 mL of either bupivacaine (5 mg/mL) or ropivacaine (7.5 mg/mL) was injected. Subsequently, bupivacaine (2.5 mg/mL) and ropivacaine (3.75 mg/mL) were continuously infused over 6 h. Control animals were treated with corresponding volumes of normal saline. Finally, muscle samples were dissected at injection sites. After processing and staining, histological patterns of muscle damage were blindly examined, scored (0 = no damage to 3 = myonecrosis), and statistically analyzed. After normal saline, only interstitial edema was found. Bupivacaine treatment caused severe tissue damage (score, 2.3 +/- 0.7), whereas ropivacaine induced fiber injury of a significantly smaller extent (score, 1.3 +/- 0.8). Furthermore, bupivacaine, but not ropivacaine, induced apoptosis in muscle fibers. In summary, both drugs induce muscle damage with similar histological patterns. Compared with bupivacaine, which induces both necrosis and apoptosis, the tissue damage caused by ropivacaine is significantly less severe. We conclude that ropivacaine's myotoxic potential is more moderate in comparison with that of bupivacaine. IMPLICATIONS: After continuous peripheral nerve blockades, the long-acting local anesthetics bupivacaine and ropivacaine both induce fiber necrosis in porcine skeletal muscle tissue. In comparison with ropivacaine, bupivacaine causes tissue damage of a significantly larger extent and additionally induces apoptosis in skeletal muscle cells.

Amides↗
PubMed2003

[Continuous bilateral sacral neuromodulation as a minimally invasive implantation technique in patients with functional bladder changes].

OBJECTIVE: Up to 50% of patients with bladder dysfunctions undergoing sacral neuromodulation treatment are non-responders. The most common treatment method today is the implantable neuromodulation system described by Tanagho and Schmidt; which allows unilateral sacral nerve stimulation. Our aim was to increase the number of responders and to improve the general efficiency of chronic sacral neuromodulation; therefore we have developed the bilateral electrode implantation by minimally invasive laminectomy. METHODS: PNE-tests were carried out to assess which patients were likely to be good responders. Thirty patients (16 with detrusor instability, 14 with hypocontractile detrusors) were subjected to minimally invasive laminectomy and received implants of bilateral electrodes. RESULTS: In those patients with a hyopcontractile detrusor, the level of residual urine of initially 350 ml was reduced to 58 ml, and the maximum detrusor pressure during micturition increased from initially 12 cMH2O to 34 cmH2O. In the other patient group with detrusor instability, the average number of incontinence incidences could be reduced from initially 7.2 to 1 per day, while the bladder capacity rose from 198 ml to 348 ml. The modulation effect did not show any signs of deteriorating in any of the patients. The follow-up period was 28 months on average. CONCLUSIONS: Clinical experience has shown that optimal neuromodulation in patients with bladder dysfunction can be achieved by this new approach involving bilateral electrode implantation. Moreover, the laminectomy implantation method guarantees a minimum of invasive trauma and enables optimal placement and fixation of the electrode.

Electric Stimulation Therapy↗
PubMedDate not supplied

Priapism - etiology, pathophysiology and management.

The understanding of erectile physiology has improved the prompt diagnosis and treatment of priapism. Priapism is defined as prolonged and persistent erection of the penis without sexual stimulation and failure to subside despite orgasm. Numerous etiologies of this condition are considered. Among others a disturbed detumescence mechanism, which may due to excess release of contractile neurotransmitters, obstruction of draining venules, malfunction of the intrinsic detumescence mechanism or prolonged relaxation of intracavernosal smooth muscle are postulated. Treatment of priapism varies from a conservative medical to a drastic surgical approach. Two main types of priapism; veno-occlusive low flow (ischemic) and arterial high flow (non-ischemic), must be distinguished to choose the correct treatment option for each type. Patient history, physical examination, penile hemodynamics and corporeal metabolic blood quality provides distinction between a static or dynamic pathology. Priapism can be treated effectively with intracavernous vasoconstrictive agents or surgical shunting. Alternative options, such as intracavernous injection of methylene blue (MB) or selective penile arterial embolization (SPEA), for the management of high and low flow priapism are described and a survey on current treatment modalities is given.

Journal Article↗
PubMedDate not supplied

Urolithiasis in children.

In general, the criteria for the treatment of urolithiasis in children are the same as those for adults. Today, extracorporeal shock wave lithotripsy (ESWL) is the method of choice in the treatment of most pediatric urinary stones. Stone-free rates between 67% and 93% at short-term follow-up, and 57% to 92% at long-term follow-up, have proven the efficacy of ESWL treatment in children. Nevertheless, the demand for auxiliary measures still remains. In order to achieve the most beneficial success rates under low complications, it is advisable to perform this type of ESWL in centers that claim the experience necessary for ESWL and endourological measures in children.

Journal Article↗