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J J Rassweiler

Publications and source records attributed to J J Rassweiler.

At least 19 recordsLinked to original sources
PubMed2001

[Laparoscopic liver donor nephrectomy. Personal experiences and review of the literature].

Despite improved success rates, the number of kidney transplantations in Germany in the last few years has stagnated, resulting in increasing waiting lists of patients on dialysis. In Germany, only 16.7% of kidney transplantations are living-donor nephrectomies, representing a relatively low rate compared to other countries (The Netherlands 28%, Sweden 35%). Since April 1998, we have performed ten retroperitoneoscopic living-donor nephrectomies (six left, four right side). The mean operating time was 216 min (155-290) with minimal blood loss. No intraoperative complications were observed. Warm ischemia time amounted to a mean of 4 min (2-7). The mean cold ischemia time was 165 min (76-290). Postoperative hospital stay of the donors was 6 days (4-10). All transplants functioned immediately; mean serum creatinine dropped from initially 8.0 mg/dl (5.3-11.5) on day 1 to 1.4 mg/dl (0.9-1.6) 3 months after surgery. This did not differ from previously operated open donor nephrectomies. An analysis of the literature included data of 4240 patients from 25 publications between 1980 and 2000 reporting on either open or laparoscopic living donor nephrectomies.

Adult↗
PubMed2001

Retroperitoneal laparoscopic nephropexy.

Laparoscopic nephropexy is a suitable and clinically established procedure for the treatment of symptomatic nephroptosis. The availability of a minimally invasive therapy can facilitate decisions regarding the indication after careful selection of patients.

Adolescent↗
PubMed2001

Proposal for a "European Scoring System for Laparoscopic Operations in Urology".

PURPOSE: To propose a scoring system of difficulties for the most currently performed laparoscopic procedures in urology. MATERIALS AND METHODS: Each current laparoscopic procedure has been evaluated according to three different criteria: technical difficulty, operative risk and the attention required. Each criterion is scored from 1 (minimal impact of the criteria) to 7 (maximal impact of the criteria). The sum of the 3 criteria is used to classify each operation according to an increasing level of global difficulty, classified into 6 levels: easy (E: sum of criteria between 3 and 5), slightly difficult (SD: sum of criteria between 6 and 8), fairly difficult (FD: sum of criteria between 9 and 11), difficult (D: sum of criteria between 12 and 14), very difficult (VD: sum of criteria between 15 and 17), extremely difficult (ED: sum of criteria greater than 18). RESULTS: Procedures currently performed by laparoscopy have been selected for evaluation according to the above criteria, and retrospectively validated by European experts in laparoscopic urology according to their experience and the international literature. CONCLUSION: This proposal of a scoring scale system is a basis for discussion, teaching and learning of urological laparoscopy. By necessity, this scale is evolving and will be regularly reconsidered and updated every 5 years.

Humans↗
PubMed2001

Future developments and perspectives in laparoscopy.

INTRODUCTION: As urologists head into the new millennium, it has become clear that laparoscopy will play a significant role in successful urologic practice. Issues that are addressed in this article include: (1) What are the new limits? (2) Technological advances. (3) Adequate training. (4) How to technically simplify the laparoscopic procedures? MATERIALS AND METHODS: To answer the stated questions a review of the literature has been undertaken together with interviews of the leading experts and laparoscopic working groups in urologic laparoscopy. The gathered information has been summarized and focussed with the aim of presenting the perspectives of laparoscopy in urology. RESULTS AND DISCUSSION: Standardized indications for laparoscopic urological surgery are benign nephrectomy, nephroureterectomy, cryptorchidism, adrenalectomy, renal cysts, lymphocele and bilateral or relapsing varicocele. Future indications might include living donor nephrectomy, partial nephrectomy and cyst decortication for adult polycystic kidney disease. Controversy exists about the laparoscopic treatment of malignancies in the urinary tract. Whereas pelvic lymph node dissection--even if performed with decreasing frequency--is accepted worldwide, retroperitoneal lymphadenectomy for low-stage testis cancer is currently performed only at few centers. The recent breakthrough in uro-oncological laparoscopic surgery has been laparoscopic radical prostatectomy changing our views on the limits of laparoscopic urology. Endoscopic suturing devices (i.e. Endostitch) are further being developed, and a prototype reapproximating micro-clips (VCS stapler) has been used to perform a uretero-ureterostomy laparoscopically in a porcine model. Nevertheless, the ability of endoscopic suturing using the standard equipment has still to be considered as a "conditio sine qua non". Improvements for tissue division and dissection include an electrosurgical snare to perform a partial nephrectomy, the development of a pneumodissector and hydrodissector. Robotics, including the AESOP 3000 and ZEUS represent a glimpse of the future. By positioning the optique in a voice-controlled full range motion mechanic arm, the image on the screen is very steady and the ergonomics of the surgeons is increased significantly. The da Vinci-System, however, is the first system that has translated all visions of telepresence surgery into clinical reality, recently also for laparoscopic radical prostatectomy. CONCLUSIONS: The future of laparoscopic urology is a two-tiered approach. On the first tier, the advancement of complex reconstructive and ablative surgery such as laparoscopic prostatectomy or, laparoscopic retroperitoneal node dissection, will be undertaken by referral centers of expertise. It is from these individuals that we will look to in order to separate what is feasible and what is reasonable. The second tier will be focusing on simplifying the procedure for the average urologist. As such, developments such as the pneumodissector, hydrodissection, and hand assistance will bring exstirpative laparoscopy into the realm of more urologists. What is critical is that the urologic community supports both groups of laparoscopists.

Education, Medical, Graduate↗
PubMed2001

Treatment of renal stones by extracorporeal shockwave lithotripsy: an update.

AIM: Despite the extensive experience with minimal invasive stone therapy, there are still different views on the ideal management of renal stones. MATERIALS AND METHODS: Analysis of the literature includes more than 14,000 patients. We have compared these data with long-term results of two major stone centers in Germany. The results have been compared concerning the anatomical kidney situation, stone size, stone localization and observation time. RESULTS: According to the importance of residual fragments following extracorporeal shock wave lithotripsy (ESWL), we have to distinguish between clinically insignificant residual fragments and clinically significant residual fragments (CIRF). 24 months following ESWL stone passage occurs as a continuous process, and if there are no clinical symptoms, any endoscopic procedure should be considered as overtreatment. According to these results, stone-free rates of patients increase in longer follow-up periods. Newer ESWL technology has increased the percentage of CIRF. CONCLUSION: We consider ESWL in most patients with renal calculi as first-line treatment, except in patients with renal calculi bigger than 30 mm in diameter.

Humans↗
PubMed2000

Laparoscopic partial nephrectomy. The European experience.

Laparoscopic partial nephrectomy is technically difficult but oncologically effective. The operation should be performed in centers with expertise. Hemostasis can be achieved using bipolar coagulation and fibrin glue-coated cellulose. Further studies will determine whether less invasive alternatives (focused ultrasound, cryotherapy) will meet the high standard of open (or laparoscopic) nephron-sparing surgery for small renal cell carcinoma.

Carcinoma, Renal Cell↗
PubMed2000

Retroperitoneoscopic and laparoscopic suturing: tips and strategies for improving efficiency.

BACKGROUND: The difficulties of minimally invasive reconstructive surgery, laparoscopically or retroperitoneoscopically, are caused by spatial limitation and fixed trocar positions and, therefore, restricted movement and handling of the instruments. In addition to a standardization of the technique, continual training, and improved instrument technologies, optimization of the geometry of reconstructive surgery, such as angles and distances between the working ports or the camera and needle position, are imperative to providing an optimal clinical performance. MATERIALS AND METHODS: After designing a standardized suturing technique and conducting an experimental analysis of the geometric factors important in reconstructive surgery, we transferred these results to our clinical setting. A series of 116 reconstructive laparoscopic and retroperitoneoscopic procedures (nephropexy, pyeloplasty, bladder neck suspension, and radical prostatectomy) were analyzed according to the technical realization and quality of reconstruction. Trocar and table positions were adjusted according to our preliminary results, as were the position of the instruments and camera. RESULTS: The trocar and instrument positions are critical for the clinical outcome of reconstructive surgery. Continual training in a standardized suturing technique, together with the clinical application of the important geometric rules, can reduce surgery time by 50%. The time required for suturing single knots could be decreased even more: as much as 75%, thus ensuring efficient and safe reconstructive surgery. CONCLUSION: Reconstructive procedures such as pyeloplasty or radical prostatectomy can be standardized and performed in an acceptable amount of time with adequate quality when adhering to a standardized technique and the important geometric rules. Improved performance in terms of time and quality will increase the acceptance of these procedures, which can help to solve the problem associated with a low total number of indications for laparoscopy and retroperitoneoscopy.

Equipment Design↗
PubMed2000

Long-term experience with laparoscopic retroperitoneal lymph node dissection in the management of low-stage testis cancer.

OBJECTIVES: We describe our experience with laparoscopic retroperitoneal lymphadenectomy (LRLA) in 34 patients with low-stage germ cell tumors treated from 1992 to 1998. All patients had clinical stage-I disease with no clinical evidence (CT scan, ultrasound, tumor markers) of metastases. A laparoscopic dissection was used to assess the pathologic status of the relevant retroperitoneal lymph nodes. MATERIAL AND METHODS: 17 patients were treated by a transperitoneal laparoscopic approach, whereas in the last 17 patients retroperitoneoscopic retroperitoneal lymph node dissection was performed. The lymph node dissection was performed identically to open surgery with the modified template according to Weissbach including the paracaval, interaortocaval, upper pre-aortic, and right common iliac zonal nodes for right-sided tumors, and para-aortic, upper pre-aortic zones for left-sided tumors. Retrieval of the lymph node chains was accomplished using a small organ bag. RESULTS: The procedure could be completed successfully in 30 of 34 patients with stage-I disease. In these cases the mean duration of the procedure was 248 min. In 3 patients the lymphadenectomy was abandoned, because frozen section showed metastasis. In 1 case conversion to open surgery was necessary because of bleeding from the aorta. One patient developed a delayed ureteral stenosis which required operative repair. Three patients required temporary insertion of an indwelling ureteral stent, and another patient had a pulmonary embolism with an uneventful outcome. One patient with a LRLA on the right side later developed retrograde ejaculation. In 6 of the 33 patients (18%) embryonal carcinoma or mixed carcinoma was found. The postoperative hospital stay averaged 5.3 (3-9) days for the patients without complications or conversion to open surgery. After a median follow-up of 40 months no regional relapse occurred, but 2 patients developed pulmonary metastases which were treated successfully by three cycles of platinum-based chemotherapy. All patients have no evidence of disease. CONCLUSIONS: Our experience suggests that LRLA is a safe and accurate method for low-stage germ cell tumors with minimal invasiveness, but because of its technical difficulty it should be restricted to experienced centers.

Follow-Up Studies↗
PubMed1999

Retroperitoneoscopic renal surgery: our approach.

INTRODUCTION: In the United States and Europe, the retroperitoneoscopic approach to renal surgery has generally been less popular than the transperitoneal laparoscopic approach, primarily because of its "smaller" working space and surgeons' relative unfamiliarity with the optimal operative technique. Presented herein are our current techniques, developed in more than 400 retroperitoneoscopic renal procedures at two major centers performing urologic laparoscopic surgery. TECHNICAL CONSIDERATIONS: Creation of an adequate working space in the retroperitoneum outside of, and posterior to, Gerota's fascia is a critical first step. At one institution, this working space is created with a balloon dilator; at the other, finger dissection is employed for this purpose. A longitudinal incision is made in Gerota's fascia, parallel and close to the psoas muscle, to access the renal hilum. During nephrectomy, the renal hilum is approached initially, followed subsequently by mobilization of the specimen. CONCLUSION: Retroperitoneoscopy allows superb, early access to the renal hilum while avoiding the peritoneal cavity, and is our preferred approach for performing most laparoscopic renal surgery, including radical nephrectomy for cancer. The techniques we describe have made retroperitoneoscopy a dependable, user-friendly, and routine approach for minimally invasive surgery of the kidney at our two centers.

Humans↗
PubMed1998

[Retroperitoneoscopy--experiences with the first cases].

UNLABELLED: A retroperitoneal access is most commonly applied for open procedures in urology. With introduction of the balloon dissecting technique, this anatomical route could also be used for laparoscopic surgery. MATERIALS AND METHODS: From 12/1992 to 10/1997, a total of 200 retroperitoneoscopic procedures have been performed in 197 patients (age 4-82 years): 78 nephrectomies, 50 renal cyst resections, 14 nephropexies, 11 ureterolyses, 8 retroperitoneal lymph-node dissections, 8 renal biopsies, 6 adrenalectomies, 6 heminephrectomies, 6 pyeloplasties, 5 ureterolithotomies, 6 ureterocutaneostomies and 2 others. Thirty-eight patients (19%) had undergone previous abdominal surgery; 22 (11%) had had kidney and ureter operations. Dissection of the retroperitoneal space was done with a balloon catheter in 14 or a balloon trocar system in 93 cases, and in the last 93 patients digital dissection with the index finger proved to be sufficient. RESULTS: We classified 76 as simple (i.e., renal biopsy, renal cyst resections, ureterocutaneostomy) and 102 as difficult (i.e. adrenalectomy, nephrectomy, nephropexy) and 22 (11%) as very difficult operations (i.e., pyeloplasty, heminephrectomy, lymphadenectomy). There has been a significant learning curve during the first 50 cases as reflected by increased operating time and complications and the conversion rate to open surgery. After that, the OR times mainly depended on the difficulty of the procedure, averaging 45-100 min for an easy retroperitoneoscopy, 95-185 min for a difficult and 185-240 min for a very difficult operation. In the last 50 cases, the complications, conversion and reintervention rate have become comparable to open surgery (2, 4 and 2%). CONCLUSIONS: After more than 200 cases of retroperitoneoscopy, the access technique has been significantly simplified. The procedure is standardized, safe and reproducible.

Adolescent↗
PubMed1998

Retroperitoneoscopy: experience with 200 cases.

PURPOSE: A retroperitoneal access is commonly used for open urological procedures. Since the introduction of the balloon dissecting technique by Gaur this anatomical route has also been used for laparoscopic surgery. We present our experience with retroperitoneoscopy in 200 cases. MATERIALS AND METHODS: From December 1992 to October 1997 a total of 200 retroperitoneoscopic procedures were performed in 197 patients 4 to 82 years old, comprising 78 nephrectomies, 50 renal cyst resections, 14 nephropexies, 11 ureterolyses, 8 retroperitoneal lymph node dissections, 8 renal biopsies, 6 adrenalectomies, 6 heminephrectomies, 6 pyeloplasties, 5 ureterolithotomies, 6 ureterocutaneostomies and 2 others. Of the patients 38 (19%) and 22 (11%) had undergone previous abdominal surgery, and kidney and ureter operations, respectively. Dissection of the retroperitoneal space was enabled by the use of a balloon catheter in 14, balloon trocar system in 93 and finger dissection technique in 93 cases. RESULTS: We classified 76 procedures (38%) as simple (renal biopsy, renal cyst resections, ureterocutaneostomy), 102 (51%) as difficult (adrenalectomy, nephrectomy, nephropexy) and 22 (11%) as very difficult (pyeloplasty, heminephrectomy, lymphadenectomy). There was a significant learning curve during the first 50 cases reflected by longer operating time, and higher complication, conversion to open surgery and open reintervention rates (14, 10 and 6%, respectively). In addition to the learning curve, mean operating time depended on the difficulty of the procedure, averaging 45 to 100 minutes for a simple, 95 to 185 for a difficult and 185 to 240 for a very difficult retroperitoneoscopy. In the last 50 cases the complication, conversion and reintervention rates (2, 4 and 2%, respectively) were acceptable for routine clinical application. CONCLUSIONS: After experience with more than 200 cases of retroperitoneoscopy the access technique has been significantly simplified. The procedure is standardized, safe and reproducible.

Adolescent↗
PubMed1998

Retroperitoneal and pelvic extraperitoneal laparoscopy: an international perspective.

OBJECTIVES: To assess technical preferences and current practice trends of retroperitoneal and pelvic extraperitoneal laparoscopy. METHODS: A questionnaire survey of 36 selected urologic laparoscopic centers worldwide was performed. RESULTS: Twenty-four centers (67%) responded. Overall, 3988 laparoscopic procedures were reported: transperitoneal approach (n = 2945) and retroperitoneal/extraperitoneal approach (n = 1043). Retroperitoneoscopic/extraperitoneoscopic procedures included adrenalectomy (n = 74), nephrectomy (n = 299), ureteral procedures (n = 166), pelvic lymph node dissection (n = 197), bladder neck suspension (n = 210), varix ligation (n = 91), and lumbar sympathectomy (n = 6). Mean number of total laparoscopic procedures performed in 1995 per center was 41 (range 5 to 86). Major complications occurred in 49 (4.7%) patients and included visceral complications in 26 (2.5%) patients and vascular complications in 23 (2.2%). Open conversion was performed in 69 (6.6%) patients, electively in 41 and emergently in 28 (visceral injuries, n = 16; vascular injuries, n = 1 2). Retroperitoneoscopy/extraperitoneoscopy is gaining in acceptance worldwide: in 1993, the mean estimated ratio of transperitoneal laparoscopic cases versus retroperitoneoscopic/ extraperitoneoscopic cases per center was 74:26; however, in 1996 the ratio was 49:51. CONCLUSIONS: Retroperitoneoscopy and pelvic extraperitoneoscopy are important adjuncts to the laparoscopic armamentarium in urologic surgery. The overall major complication rate associated with retroperitoneoscopy/extraperitoneoscopy was 4.7%.

Humans↗
PubMed1997

[Techniques for bladder neck suspension with osseous screw fixation].

We investigated the technical feasibility and clinical results of bone fixation techniques in combination with needle suspension for correction of female stress urinary incontinence. In our experience the screw-like bone anchor, which is drilled into the public tubercle, represents a minimally invasive but very stable and reliable technique. However, the needle suspension fixed to the bone anchor turned out to be critical. Even though the suspension was fixed in the paraurethral tissue with a deep Z-stitch between the bladder neck and the midurethra, the 1-year recurrence rate was 76%. Our data showed that the suspension sutures pull through the paraurethral tissue because there is no paravesical scar formation as in open procedures. Modifications of the suspension technique (four-point suspension, simultaneous laparoscopic or digital dissection of the paravesical space, combination with sling procedures) revealed significantly improved short-term results. Therefore we conclude that after improvement of the suspension technique the bone anchor will represent a valid option for minimally invasive fixation of a bladder neck suspension.

Bone Screws↗
PubMed1996

New methods of searching for medical literature: comparison of two systems, implementation and user reactions in a urologic department.

Knowledge Finder is the first Medline retrieval system based on CD-ROM technology that allows natural-language queries and accounts for deviations in spelling and terminology. Retrieved citations are ranked in accordance with their possible relevance (fuzzy logic algorithms), thus resulting in speedy orientation on a topic of interest. EasyOrder is an additional software module that enables the user to place an automatic electronic order at the library of choice, via modem, to receive a copy of a full-text article by mail or facsimile. We performed a study comparing search results and times when using a Boolean versus a fuzzy system. This article describes the underlying new concepts, implementation in a urologic department and user reactions to the new possibilities.

CD-ROM↗
PubMed1996

Laparoscopic retroperitoneal lymph node dissection for nonseminomatous germ cell tumors: indications and limitations.

PURPOSE: We describe our experience with laparoscopic retroperitoneal lymph node dissection in 26 patients with nonseminomatous germ cell tumors: 17 had stage I disease with no clinical (computerized tomography, ultrasound or tumor markers) evidence of metastases and 9 (2 with stage IIb and 7 with stage IIc disease) had residual tumor after chemotherapy but with negative tumor markers. Laparoscopic dissection was performed to assess more fully pathological status of the relevant retroperitoneal lymph nodes in both groups. MATERIALS AND METHODS: The patient was positioned and trocars were introduced at sites similar to that used for transperitoneal laparoscopic nephrectomy (flank position with 3, 10 mm. and 2, 5 mm. ports). After the white line of Toldt was incised and the colon was reflected anteromedially, the retroperitoneal space was exposed. The landmarks of lymph node dissection were then isolated, including the ureter, aorta, inferior vena cava and both renal veins. Lymph node dissection was performed identical to that for open surgery, with a modified template including the paracaval, interaortocaval, upper preaortic and right common iliac nodes for right tumors, and para-aortic and upper preaortic nodes for left tumors. Lymph node chains were retrieved with a small organ bag. RESULTS: The procedure was completed successfully in 16 of 17 patients with stage I disease (mean duration 268 minutes for the left and 312 minutes for the right sides). No intraoperative complications were encountered. One patient had delayed ureteral stenosis requiring operative repair, 1 had a pulmonary embolism with an uneventful outcome and 1 who underwent laparoscopic retroperitoneal lymph node dissection on the right side later had retrograde ejaculation. Embryonal carcinoma was found in 1 of the 17 patients. Average postoperative hospital stay was 4.5 days for patients without complications or conversion to an open procedure. After a median followup of 27 months no patient had regional relapse but 2 had pulmonary metastases that were treated successfully with 3 cycles of platinum based chemotherapy. Laparoscopic dissection was significantly more difficult in patients with stage II tumors after chemotherapy. Only in 2 patients with stage IIb disease was laparoscopic lymphadenectomy successful. In 5 of the 7 patients with stage IIc cancer portions of the dissection had to be done after conversion to an open (conventional) operation via a small incision (suprainguinal or pararectal). In 1 patient the laparoscopic approach was completely abandoned and converted to an open operation via a standard midline incision. In all 9 cases histopathological examination revealed complete necrosis. No patient has evidence of disease. CONCLUSIONS: Our preliminary experience suggests that a modified laparoscopic retroperitoneal lymph node dissection is feasible for stage I tumors. However, it cannot be recommended after previous chemotherapy (stages IIb and IIc disease).

Follow-Up Studies↗
PubMed1996

[Laparoscopy].

Explore the source record for details and available documents.

Diffusion of Innovation↗
PubMed1996

[Retroperitoneoscopy. Technique and experiences with the first 100 patients].

Retroperitoneoscopic procedures were already being performed in the late 1970s. The clinical breakthrough of retroperitoneoscopy, however, was initiated in 1992 by the balloon-dissecting technique of Gaur, together with the experience gained with transperitoneal laparoscopic procedures in the upper retroperitoneum. We have modified the balloon-dissecting technique into a hydraulic video-optically controlled balloon dissection of the retroperitoneal space, and this procedure was recently further simplified. From December 1992 to December 1995 we performed 100 retroperitoneoscopic procedures in 98 patients (aged 4-82 years). Twenty-two patients had undergone previous abdominal surgery, 16 patients had been operated on for kidney and ureter problems. We performed 28 simple procedures (6 renal biopsies, 17 renal cyst resections, 4 ureterocutaneostomies, 1 foreign body retrieval), 65 difficult operations (47 nephrectomies, 5 nephroureterectomies, 5 nephropexies, 4 ureterolithotomies, 2x ureterolysis). There were also 9 complicated cases (5 heminephrectomies, 2 tumor nephrectomies, 2 dismembered pyeloplasties). Operating time, complications and conversion rate to open surgery mainly depended on the difficulty of the procedure and the personal learning curve, resulting in 50-90 min, 0% and 3.8%, respectively, for an easy retroperitoneoscopy, 90-210 min, 12% and 9.2% respectively for a difficult operation, and 180-390 min, 22% and 11%, respectively, for a very difficult procedure. Excluding the 17 patients with complications or conversion (unclear anatomy, extremely difficult dissection), the mean postoperative need for analgesics was 0.7 vials, and the mean hospital stay was 4.7 days. We have now passed most of our learning curve, and retroperitoneoscopy has become a standardized procedure that is a part of the training program for the experienced urologist.

Biopsy↗