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J Rassweiler

Publications and source records attributed to J Rassweiler.

At least 19 recordsLinked to original sources
PubMed2006

[The position of laparoscopic surgery in pediatric urology].

With growing experience in laparoscopic techniques there is a switch in pediatrics from ablative surgery to reconstructive procedures. Besides the established procedures such as laparoscopic nephrectomy and orchidopexy, procedures like heminephrectomy and pyeloplasty have proven practicable and become standard therapies in children and infants. Due to technical advances, as shown for our own patients, the number of treated infants is still increasing. However, laparoscopic reconstructive procedures presuppose a good deal of experience in preparation and suture techniques, and remain reserved for centers with daily experience in laparoscopy. Daily experience with difficult urological laparoscopic procedures in adults will remain more common than in pediatric centres.

Child↗
PubMed2006

[Laparoscopic pelvic surgery: Where do we stand in the year 2006?].

Laparoscopic radical prostatectomy has become an equivalent alternative to the open retropubic approach, offering the advantages of minimally invasive surgery. It is being applied increasingly in Germany and the rest of Europe. Whether the surgical robot da Vinci will be used for this procedure to the same extent as in the United States is unpredictable because of high investment and maintenance costs. Similarly, laparoscopic sacrocolpopexy has proven to be a viable option compared to open transabdominal or transvaginal surgery, showing a significant reduction in postoperative morbidity. The value of radical cystectomy is controversial despite proven feasability. On one hand, the technical difficulties of purely laparoscopic urinary diversion result in very long operating times, and in the case of the laparoscopically assisted creation of a neobladder, the advantage of this approach has to be questioned. On the other hand, a maximum rate of 30% of local recurrences and distant metastases indicates at least poor patient selection. In conclusion, this procedure should be limited to a few experienced centers.

Cystectomy↗
PubMed2005

[Ureteral injuries. Diagnostic and treatment algorithm].

The most common cause of iatrogenic injuries to the ureter (75%) is a gynecological or surgical pelvic procedure. The diagnosis of ureteral injuries is delayed in 66% (after days or weeks). Lack of hematuria is an unreliable sign to exclude injury, since 30% of all ureteral injuries do not even demonstrate microscopic hematuria or classic clinical symptoms and signs. In view of this, the diagnosis must be one of suspicion and further evaluations are mandatory in all cases of penetrating or blunt abdominal injuries. The most accurate diagnostic tools are CT scan with delayed excretory images and retrograde ureterography, which can also be used to guide stent placement. Low-grade injuries can be sufficiently treated with urinary diversion by PCN drainage or endoscopic ureteric stenting. The treatment of high-grade injuries depends on the localization and extent of the damage. The principles of repair include débridement, spatulation, lack of tension, stenting, postoperative drainage, and a watertight anastomosis with fine nonreactive absorbable suture. A delay in diagnosis is the most important factor contributing to the morbidity of ureteric injuries, and early treatment can reduce the complication rate to below 5%.

Algorithms↗
PubMed2005

Robotics and telesurgery--an update on their position in laparoscopic radical prostatectomy.

Laparoscopy is handicapped by the reduction of the range of motion from six to only four degrees of freedom. In complicated cases (i.e. radical prostatectomy), there is often a crossing of the hands of surgeon and assistant. Finally, standard laparoscopes allow only 2D-vision. This has a major impact on technically difficult reconstructive procedures such as laparoscopic radical prostatectomy. Solutions include the understanding of the geometry of laparoscopy, but also newly developed surgical robots. During the last five years, there has been an increasing development and experience with robotics in urology. This article reviews the actual results focussing on the benefits and problems of robotics in laparoscopic radical prostatectomy. Own experiences with robot-assisted surgery include more than 1200 laparoscopic radical prostatectomies using a voice-controlled camera-arm (AESOP) as well as six telesurgical interventions with the da Vinci-system. Substantial experimental studies have been performed focussing on the geometry of laparoscopy and new training concepts such as perfused pelvitrainers and models for simulation of urethrovesical anastomosis. The recent literature on robotics in urology has been reviewed based on a MEDLINE/PUBMED research. The geometry of laparoscopy includes the angles between the instruments which have to be in a range of 25 degrees to 45 degrees ; the angles between the instrument and the working plane that should not exceed 55 degrees ; and the bi-planar angle between the shaft of the needle holder and the needle which has to be adapted according to the anatomical situation in range of 90 degrees to 110 degrees . 3-D-systems have not yet proved to be effective due to handling problems such as shutter glasses, video helmets or reduced brightness. At the moment, there are only two robotic surgical systems (AESOP, da Vinci) in clinical use, of which only the da Vinci provides stereovision and all six degrees of freedom (DOF). To date, more than 3000 laparoscopic radical prostatectomies have been performed worldwide at 92 centres with this system. The main advantage of the system represents the translation of open surgical skills to laparoscopy. Despite recent development of basic tools (e.g. bipolar forceps) for the da Vinci robot, investment and maintenance costs still represent the major problem of the device. Additionally, the device does not provide any haptic sense (i.e. tactile feedback). Robotic surgery represents a turning point of surgical research. However, broad use of robotic systems is limited mainly because of the high investment and running costs. Interestingly, more than in the field of cardiac surgery, there seems to be a need for telemanipulators in urology, mainly to reduce the learning curve of standard laparoscopy. However, new training concepts used in combination with mono-tasking computerized robots (AESOP) have proved their efficacy associated with a significant cost reduction.

Journal Article↗
PubMed2004

Transperitoneal laparoscopic radical prostatectomy: ascending technique.

BACKGROUND AND PURPOSE: To demonstrate the operative steps of transperitoneal laparoscopic radical prostatectomy with the ascending approach (Heilbronn technique). PATIENTS AND METHODS: The technique is based on our experience with more than 1000 cases of clinically localized prostate cancer from March 1999 to April 2004. The technical steps, instrumental requirements, patient data, complications, and reintervention rate were reviewed. RESULTS: The principles of the technique include the routine use of a voice-controlled robot (AESOP) for the camera, exposure of the prostatic apex with 120 degree retracting forceps, free-hand suturing for Santorini plexus control, application of 5-mm clips during the nerve-sparing technique, control of the prostatic pedicles by 12-mm Hem-o-Lock clips, the bladder neck-sparing technique in patients with stage T1c and T2a tumors, and use of interrupted sutures for the urethrovesical anastomosis. A considerable improvement was observed when comparing the first 300 with the most recent 300 cases (mean operating time 280 v 208 minutes; conversion rate 2.7% v 0.3%; reintervention rate 3.7% v 1.0%). CONCLUSIONS: Through our experience with more than 1000 cases, transperitoneal access for laparoscopic radical prostatectomy has proven to be feasible and transferable with results comparable to those of the original open approach. Besides the well-known advantages of minimally invasive surgery, the video endoscopic approach may offer further benefits in permitting optimization of the technique by video assessment.

Adult↗
PubMed2003

Present practice and development of minimally invasive techniques, imaging and training in European urology: results of a survey of the European Society of Uro-Technology (ESUT).

OBJECTIVES: The European Society of Urological Technology (ESUT) conducted a survey in order to assess and record the current trend between European urologists with regard to the application of new technologies in BPH, stone disease and imaging and to identify differences amongst urologists. MATERIAL AND METHODS: A total of 854 certified urologists and residents coming from European countries answered the ESUT survey during the XVIth Annual EAU Meeting in Geneva in 2001. The respondents were classified according to the geographical origin (Eastern, Southern and Northern Europe), year of certification (before 1980, and every 5 years hereafter) and power of the department in beds (less than 25, 26-50, and more than 50) in order to identify any differences in the replies mainly due to economical reasons, national or hospital policy and personal attitudes. RESULTS: According to the replies, in Eastern Europe more procedures related to BPH and stones are performed comparing to Northern and Southern Europe (165.8 versus 77.1 and 100.6/month/department, respectively). However, the Northern European urologists have access to every type of lithotriptor and most of the different minimally invasive treatments for BPH in a higher percentage, followed by the Southern and the Eastern European urologists. The most widespread intracorporeal lithotriptor is the pneumatic and the most common alternative minimally invasive BPH treatment is electrovaporization (80.7% and 45.6%, respectively). Holmium laser is the most frequent choice (40.1%) when the surveyed urologists were asked to choose which of the minimally invasive techniques would like to have access to. In total 79.4% (54.1% alone and 25.3% in collaboration with the radiologists) of the respondents perform the ultrasound studies while the remaining 20.6% declare that only the radiologists do the studies. Of the surveyed urologists, 92.8%, 89.6% and 94.9% are interested in hands-on courses, simulators and live surgery, respectively. CONCLUSIONS: The data obtained from the 854 surveyed European urologists and residents can be used as a tool to highlight the disparity between European countries and to advance training of European urologists.

Cohort Studies↗
PubMed2002

[Minimally invasive therapy of obstruction of the kidney pelvis].

We report on 109 patients with ureteropelvic junction obstruction (UPJO) treated according to the following algorithm: intrinsic stenoses were treated by laser endopyelotomy (LEP). We used retroperitoneoscopy with ureterolysis to manage significant extrinsic UPJO due to a crossing vessel and either non-dismembered pyeloplasty in cases of an anterior vessel or dismembered pyeloplasty in cases of a posterior crossing vessel. Children were mostly treated by open dismembered pyeloplasty. Analysis of the factors that influence the postoperative results in the group of 64 patients treated by LEP showed significance for the presence of extrinsic causes of UPJO and the underlying grade of hydronephrosis. Based on our own results and the review of the literature, minimally invasive approaches for the management of UPJO have been proven safe and effective with results comparable to open surgery.

Adolescent↗
PubMed2002

[Geometry of laparoscopy, telesurgery, training and telementoring].

Laparoscopic surgery in general is handicapped by the reduction of the range of motion from 6 to 4 degrees of freedom. This has a major impact on technically difficult procedures such as laparoscopic radical prostatectomy. Solutions for this problem include understanding the geometry of laparoscopy with sophisticated training programs, but also newly developed surgical robots, computer simulators, and telementoring. This article evaluates the value of these alternatives based on own experience and an analysis of the current literature. Our experience with robot-assisted surgery includes 244 laparoscopic radical prostatectomies using a voice-controlled camera arm (AESOP) and 6 telesurgical interventions with the da Vinci system. Additionally, experimental studies were performed focussing on the geometry of laparoscopy and new training concepts such as perfused pelvitrainers and computer simulation. Three-dimensional systems have not yet proved to be effective due to handling problems such as shutter glasses, video helmets, or reduced brightness. At present, there are only two robotic surgical systems (ZEUS, da Vinci) in clinical use for telesurgery, of which only the da Vinci provides stereovision and all 6 degrees of freedom (DOF). In the meantime, more than 100 laparoscopic radical prostatectomies have been performed with this system. However, there was no evidence of any advantages over the conventional laparoscopic approach. The ZEUS in combination with the telecommunication system SOKRATES is the only device that enables telemanipulation and telementoring over long distances (i.e., transatlantic). Robotic surgery represents a turning point in surgical research. However, broad use of robotic systems is limited mainly because of high investment and running costs. Whereas audiovisual telementoring will play a clear role in future training concepts, the need for telemanipulation or telesurgery has not yet been clarified.

Computer Simulation↗
PubMed2002

[Results of comprehensive data collection concerning urologic laparoscopy].

To evaluate the current status of laparoscopy, the "Working Group Laparoscopy" of the German Urological Association performed a questionnaire among urologists in Germany. Of 300 questionnaires 183 were returned and analyzed (61%): 54% of the departments already performed laparoscopy and another 50% are planning to introduce this technique. The major concerns are economical (70%), long learning curve (92%), investment (53%), and lack of scientific data (76%). Simple nephrectomy, cryptorchism, and varicoceles are treated by 66, 59, and 58 of the 96 departments laparoscopically (of 183 resp.). Laparoscopic surgery for radical prostatectomy and tumor nephrectomy is done by 32 and 34 of 96 departments. Only a minority of the centers performs more than 40 laparoscopies per year and indication. Compared to a survey conducted in 1995, the acceptance level of this technique has increased (100% vs 48%). Only a minority of the departments performs more than 40 laparoscopic interventions per year for one indication.

Attitude of Health Personnel↗
PubMed2002

Renal chemoembolization with mitomycin c/Ethibloc: pharmacokinetics and efficacy in an animal model.

BACKGROUND AND PURPOSE: Arterial embolization can be an alternative treatment for kidney malignancy. We investigated the efficacy of renal embolization with a combination of an occlusive agent (Ethibloc) and the cytotoxic substance mitomycin C (MMC) in an animal model. MATERIALS AND METHODS: In 32 rats with implanted Yoshida sarcoma, nephrectomy was carried out 15, 30, 60, or 90 minutes after chemoembolization (1 mg v 2 mg of MMC/mL of Ethibloc) or chemoperfusion (1 mg of MMC/mL of NaCl) of the tumor-bearing kidney. The MMC tissue concentration was measured in the kidney specimens. Six dogs also underwent chemoembolization or chemoperfusion with monitoring of MMC serum concentration at the same intervals. We compared the survival time of rats with Yoshida sarcoma after chemoembolization (N = 15), chemoperfusion (N = 18), embolization (N = 18), nephrectomy (N = 21), and no treatment (N = 25). RESULTS: The MMC tissue concentration in the rat model was much higher after chemoembolization than after chemoperfusion for at least 1.5 hours. The MMC serum concentration in the dogs showed a high initial peak (0.6 mg/L) after chemoperfusion, then dropped quickly to the same level seen 30 minutes after chemoembolization with 1 mg of MMC/mL of Ethibloc (0.15 mg/L). The MMC serum concentration following chemoembolization with 2 mg of MMC/mL of Ethibloc stayed higher (0.3-0.25 mg/L) for 60 minutes. The survival rates after nephrectomy were equal to those after chemoembolization (80% survival after 30 days), with poorer survival being seen after embolization (75%) and chemoperfusion (70%). In the control group, all rats were dead at the 27th day. CONCLUSION: Chemoembolization produces persistently high tissue concentrations of MMC and avoids toxic peak serum levels. It improves the efficacy of organ ablative vasoocclusion in renal malignancies.

Animals↗
PubMed2001

Ultrasound in endourology.

Ultrasonography was first used as a therapeutic aid in endourology in the early 1970s. Since that time, ultrasound has played an important role, and nowadays, interventional ultrasonography is an established procedure in urology. Procedures on the kidney, bladder, and prostate, which require different puncture techniques, are performed under ultrasound guidance. Today, extracorporeal shockwaves for the treatment of stones and Peyronie's disease are applied under ultrasonic control. Furthermore, high-intensity focused ultrasound (HIFU) is used experimentally for the treatment of renal tumors and, clinically, for the treatment of prostate cancer. In urologic emergencies, diagnostic and interventional ultrasonography is an important tool. Interventional ultrasound in urology has become an outstanding tool for the planning and performance of a variety of procedures, and every urologist should be able to use these technologies.

Biopsy, Needle↗
PubMed2001

Robotic and telesurgery: will they change our future?

In urology, at the end of the last millennium, there was an increasing use of computerized technology, extracorporeal shock wave lithotripsy, microwave therapy and high-energy focused ultrasound. However, experience with manipulating robots in urological surgery is still very limited. Laparoscopic surgery is handicapped by a reduction of the range of motion because of the fixed trocar position. The da Vinci system is the first surgical system to address all these problems adequately. The system consists of two main components: the surgeon's viewing and control console with three-dimensional imaging and the surgical arm unit that positions and manoeuvres detachable surgical instruments. The surgeon performs the procedure seated at the console holding specially designed instruments. Telerobotic laparoscopic radical prostatectomy provides advantages such as stereovision, dexterity and tremor filtering, but there is a learning curve with the device, mainly because of the magnification, the three-dimensional image and the lack of tactile feedback. However, after only a short period of time, the experienced surgeon is able to become familiar with the device. The impact of robotics in urological surgery is therefore very promising, and we are convinced that it will totally change the future of urological surgery.

Equipment Design↗
PubMed2001

Heilbronn laparoscopic radical prostatectomy. Technique and results after 100 cases.

INTRODUCTION: In 1999, Guillonneau and Vallancien presented a refined approach of a descending laparoscopic radical prostatectomy which based mainly on the primary access to the seminal vesicles and an improved suturing and knotting technique. Based on our own experience reconstructive laparoscopy as well as with open retropubic radical prostatectomy we have used a combined ascending/descending technique similar to open surgery. In this paper we want to describe our approach and to present the initial results with the Heilbronn technique. MATERIALS AND METHODS: A transperitoneal approach is used with a W-shaped arrangement of the trocars (13-mm umbilical port, 2 x 10 mm medial, 2 x 5 mm lateral ports). After the exposure of the Retzius' space and control of the dorsal vein complex the urethra is incised and the distal pedicles of the prostate (+/- the neurovascular bundle) are transsected. We now pull the apex ventrally and start with the incision at the bladder neck followed by a transvesical access to both vasa deferentia and seminal vesicles. The gland is entrapped in the Extraction Bag. After accomplishing the posterior wall of the urethrovesical anastomosis with five interrupted sutures, the foley catheter is placed into the bladder and the bladder neck is closed. Now the prostate is extracted via the umbilical incision. From March 1999 to June 2000, we have performed 100 cases (48 pT2-, 47 pT3- and 5 pT4 tumors). The mean preoperative PSA was 26.8 (1.4-75.5) ng/ml. Two tumors were grade 1, 72 grade 2 and 26 grade 3. Median Gleason score was 6 (3-9). All specimen were inked and examined according to the Stanford protocol. Postoperative continence was evaluated using a questionnaire monitored by a colleague who was involved in surgery. RESULTS: We had 5 conversions (rectal injury, difficult dissection, adhesion, 2x bleeding at the dorsal vein complex). The mean operating time was 278 (180-500) min., the transfusion rate 31%. One patient required reintervention due to bleeding from the right obturator fossa. 95% of the patients did not require any analgesia on the second postoperative day. Positive margins were found in 17% of the patients, of which 12 had a PSA nadir to a value of less than 0.1 ng/ml within 3 weeks after surgery. In 82 patients, the anastomosis was tight after removal of the catheter, median catheter time was 8 (6-30) days. 4% developed a stricture at the anastomotic site which could be treated by laser incision. On discharge 33% were continent, after 6 months 81%, whereas only 2 patients still suffer from grade II stress incontinence at 9 months. CONCLUSIONS: Laparoscopic radical prostatectomy is feasible but requires laparoscopic expertise. Its learning curve is still ongoing. Morbidity is low, oncological control is similar to results of open surgery, functional results are promising.

Aged↗
PubMed2001

Telesurgical laparoscopic radical prostatectomy. Initial experience.

INTRODUCTION: Telepresence surgery offers theoretically to overcome two main problems of laparoscopic surgery, i.e. the limitation to only four degrees of freedom and the lack of stereovision. Since 1998, telesurgical minimally invasive procedures have been performed with the da Vinci system mainly for cardiac bypass surgery. Clinical experience in urology is still very limited. We want to present our initial experience using the device for robot-assisted laparoscopic radical prostatectomy. MATERIAL AND METHODS: The Intuitive surgical system consists of two main components: the surgeon's viewing and control console with 3D imaging and the surgical arm unit that positions and maneuvers detachable surgical instruments. These instruments introduced via two 8-mm trocars allow movements in all 6 degrees of freedom due to the EndoWrist technology. The surgeon performs the procedure seated at the console holding specially designed instruments. Highly specialized computer software and mechanics transfer the surgeon's hand movements exactly to the microsurgical movements of the manipulators at the operative site. We have used a semilunar-shaped 5-trocar arrangement with the robot's arms at the lateral trocars and two assistant trocars medially. A sixth trocar was used in the right suprapubic area for retraction of the gland. The left assistant used different instruments such as bipolar forceps, Ultracision, Endoclip, whereas the right assistant mainly used the suction-irrigation device. Except the first case, the Intuitive System was attached after exposure of Retzius' space. RESULTS: We have treated 6 patients (2 pT2, 4 pT3, median Gleason score 6). The OR time averaged 315 (242-480) min including pelvic lymph node dissection. No intraoperative complications occurred, 1 patient required transfusions. There were no positive margins, median catheter time was 5 days. 3 patients were completely continent after 1 month. CONCLUSION: Telerobotic laparoscopic surgery offers several advantages over all presently available techniques, such as all six degrees of freedom, dexterity enhancement, tremor filtering, and stereovision. There is a learning curve with the device, mainly because of the magnification, the 3D image and the lack of tactile feedback. However, only after a short period of time, the experienced surgeon is able to get familiar with the device. However, there are still concerns with respect to the high investment and running costs of the device as well as regarding the necessity of further developments of instruments for urological procedures.

Aged↗
PubMed2001

Laparoscopic radical prostatectomy with the Heilbronn technique: an analysis of the first 180 cases.

PURPOSE: In 1998 Guillonneau and Vallancien introduced laparoscopic radical prostatectomy with primary access to the seminal vesicle. In 1999 we developed a different laparoscopic technique similar to the classic retropubic radical prostatectomy. We focus on early results and the learning curve of the procedure in the first 180 patients. MATERIALS AND METHODS: A transperitoneal approach is used with immediate access to Retzius' space. After the dorsal vein complex is endoscopically sutured, the urethra is incised and distal pedicles of the prostate with or without the neurovascular bundle transected. The apex is then pulled ventrally followed with incision at the bladder neck, and transvesical access to vas deferens and seminal vesicle. After completing the posterior wall of the urethrovesical anastomosis with 5 interrupted endoscopic sutures, the Foley catheter is placed, bladder neck closed and specimen extracted via the umbilical incision. From March 1999 to December 2000 we have performed 180 procedures, including 3 for stage pT1 tumor, 88 pT2, 82 pT3 and 7 pT4. Mean preoperative PSA was 13.3 ng./ml. (range 1.4 to 148), mean specimen weight 37.4 gm. (10 to 125) and median Gleason score 6 (3 to 9). For evaluation of the learning curve a separate analysis of 3 groups with 60 patients in each was done. Differences between groups 1 (first 60 patients) and 3 (last 60) were analyzed for statistically significant differences. RESULTS: Mean operating time was 271 minutes (range 150 to 500) and transfusion rate 31%. The reintervention rate was 4.4% and complication rate 18.8%. Of the patients 92% did not require any analgesia on postoperative day 2. Positive margins were found in 16% of the patients. The rate of positive margins in pT2 tumors was 2.3%, pT3a 15% and pT3b 34%. After a median followup of 12 months (range 3 to 23) in 9 (5%) patients a prostate specific antigen relapse was observed. The anastomosis was tight after removal of the catheter in 83% of patients, with a median time of 7 days (range 5 to 30). An anastomotic stricture had to be treated with laser incision in 3.3% of patients. On discharge from the hospital 33% of patients were continent, after 6 months 74% and after 12 months 97%. Analysis of the learning curve revealed significant differences in operating time (324 versus 265 minutes), conversion rate to open surgery (8.1% versus 1.7%), complication rate (23.3% versus 11.7%) and rate of prolonged catheterization (31.6% versus 10%, respectively), whereas the percentage of positive margins and continence rates showed no influence. CONCLUSIONS: Laparoscopic radical prostatectomy requires significant laparoscopic expertise with an ongoing learning curve. Morbidity is low, oncological control similar to results of open surgery and functional results are promising. The procedure should be performed only at dedicated centers with adequate training and expertise.

Adult↗