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J J Rassweiler

Publications and source records attributed to J J Rassweiler.

16 recordsLinked to original sources
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↗
PubMed1996

[Transperitoneal and retroperitoneal laparoscopic nephrectomy in comparison with conventional nephrectomy].

We report on our clinical experience with laparoscopic nephrectomy in 35 patients. We have performed a total of 18 transperitoneal laparoscopic nephrectomies (TLN) for benign renal disease. After the introduction of a hydraulic dissecting device, we have since performed 17 retroperitoneal laparoscopic nephrectomies (RLN). These data were compared with those in 19 consecutive open nephrectomies (N). All groups were comparable in terms of indication. The mean operative time for benign disease was 206.5 min for TLN, 211.2 min for RLN and 117 min for N. Analgesic medication requirement per patient was 2 days for TLN, 1 day for RLN and 4 days for N, while the postoperative hospital stay averaged 7 days for TLN, 6 days for RLN and 10 days for N. Our results demonstrate the advantage of a laparoscopic approach over open surgery and also reveal the distinct benefit of a retroperitoneal approach. However, due to the small number of indications this procedure should be restricted to a few urologic centers.

Humans↗
PubMed1996

[The future of laparoscopic surgery in urology].

Laparoscopy has followed the typical phases in the development of any new operative technique. We have now begun to realize its limitation and are beginning to standardize the procedures and specify their indications. Since laparoscopy predominantly reduces the trauma of access, the development of a total operative trauma score has assisted us in determining the impact of specific laparoscopic procedures compared to their open alternatives. Laparoscopy is responsible for less blood loss, less postoperative pain, a shorter hospital stay and a very small scar, all of which accounts for its popularity among patients. A rational combination of laparoscopy, endoscopy and open surgery to treat urological diseases should be developed in the future.

Forecasting↗
PubMed1996

Retroperitoneal laparoscopic lymph node dissection for staging non-seminomatous germ cell tumors before and after chemotherapy.

We describe our experience with laparoscopic retroperitoneal lymph node dissection in 19 patients with non-seminomatous germ cell tumors. Twelve patients had stage I disease with no clinical evidence (CT-scan, ultrasound, tumor markers) of metastases; 7 patients (stage IIb=2, stage IIc=5) had residual tumor after chemotherapy but with negative tumor markers. A laparoscopic dissection was used to asses more fully the pathologic status of the relevant retroperitoneal lymph nodes of both groups. The patient was positioned and trocars introduced at sites similar to that used for transperitoneal laparoscopic nephrectomy (flank position, five ports - 3 x 10 mm; 2 x 5 mm). After reflecting the colon anteromedially, the landmarks of the lymph node dissection were isolated-namely the ureter, aorta, inferior vena cava, and both renal veins. The lymph node dissection included the paracaval, interaorto-caval, upper preaortic, and right common iliac zonal nodes for right-sided tumors, and paraaortic, upper preaortic zones for left-sided tumors. Retrieval of the lymph nodal chains was accomplished using a small organ bag. The mean duration of the procedure was 298 (range 150-405) minutes. In only one patient was a lymph node positive for tumor (stage I). Otherwise nodes showed extensive necrosis (after chemotherapy). No intraoperative complications were encountered but three patients developed a delayed complication (ureteral stenosis, pulmonary embolism, and retrograde ejaculation, respectively). Whereas we completed the dissection in each patient with stage I tumors, the laparoscopic procedure was more difficult in patients with stage II tumors after chemotherapy. In two patients with stage IIb disease laparoscopic lymphadenectomy was successful. In four other patients parts of the dissection had to be done after conversion to an open (conventional) operation using a small incision (suprainguinal or pararectal); in one patient the laparoscopic approach was abandoned and converted to an open operation. In the post-chemotherapy group the outcome depended primarily on the tumor bulk prior to drug treatment. In two patients in whom all residual necrotic tissue was removed laparoscopically they had "minor" disease (stage IIb); the others had stage IIc tumors. Our preliminary experience suggests that a modified laparoscopic lymph node dissection is feasible for stage I tumors and in selected patients with marker negative residual tumor after chemotherapy (stage IIb).

Feasibility Studies↗
PubMed1995

The clinical introduction of a third generation lithotriptor: Modulith SL 20.

The Modulith SL 20* was designed as a third generation lithotriptor with outstanding disintegrative efficacy in vitro, and equipped with a combined fluoroscopic and ultrasound localization system integrated in a multifunctional table. Its introduction to clinical extracorporeal shock wave lithotripsy took place in 3 phases. In phase 1 (49 patients) only in line ultrasound localization was possible. The many caliceal stones were adequately disintegrated with restricted generator voltage. In phase 2 (81 patients) fluoroscopic localization with the virtual focus of an adapted x-ray C-arm unit enabled in situ lithotripsy of ureteral stones in 33% of all patients. Phase 3 (549 patients) was characterized by additionally increasing the generator voltage to 20 kv. This development of the lithotriptor by improving the localization system and shock wave energy resulted in the possibility for successful disintegration of stones in the entire upper urinary tract (including the complete ureter), decreased treatment time (52 to 39 minutes) and an improved efficiency quotient (0.45 to 0.67). During phase 3 auxiliary measures were performed before lithotripsy in 24% of the cases. After 1.8% of the treatments minor or moderate perirenal fluid collection or bleeding was detected by routine followup sonography. A 91% stone-free rate was achieved with only 9.3% curative auxiliary measures after extracorporeal shock wave lithotripsy, including a 23% retreatment rate. Thus, the Modulith device had a high efficacy quotient compared with other lithotriptors.

Adult↗
PubMed1994

Retroperitoneal laparoscopic nephrectomy and other procedures in the upper retroperitoneum using a balloon dissection technique.

This article describes a hydraulic balloon dissection technique. The retroperitoneum is developed via a small lumbodorsal incision between the edges of the musculus latissimus dorsi and musculus obliquus externus and then after visualization of its correct position the balloon catheter is filled with 500-1,200 ml of warm normal saline (according to patient size). The device consists of the finger of a surgeon's glove ligated around the end of a rigid bladder catheter. The balloon insufflation is maintained for 5 min to guarantee adequate hemostasis. Recently, we have replaced the balloon catheter by a balloon trocar sheath allowing direct endoscopic control of the hydraulic dissection. After retrieval of the balloon the CO2 insufflator is connected to the first trocar. All secondary trocars are placed under endoscopic control. The hydraulic dissection techniques also enable optimal creation of an effective pneumoperitoneum in children. Until now, we have used this technique for twelve procedures in the upper retroperitoneum including five nephrectomies, two nephroureterectomies, one tumor nephrectomy, one nephropexy, one renal cyst marsupialization and two renal biopsies. Up to now we have encountered no major complications. Three of the nephrectomized patients had undergone multiple previous abdominal surgical interventions. The retroperitoneal approach allows the surgeon to apply similar dissecting techniques as used in respective open procedures. It has become the routine approach for laparoscopic procedures in benign renal disease. This procedure can be performed even in cases with previous abdominal surgery.

Adult↗
PubMed1993

The technique of transperitoneal laparoscopic nephrectomy, adrenalectomy and nephroureterectomy.

In the traditional kidney position three trocars are inserted after creation of a pneumoperitoneum: 10 mm periumbilical (port I), 10/12 mm subcostal (port II) and 12/10 mm above the iliac spine (port III) in the mamillary line. After laterocolic incision the colon is dissected away from the lateral wall. Thereafter two 5-mm trocars (ports IV, V) are inserted into the lateral abdominal wall parallel to parts II and III. Following clipping and dissection of the ovarian (spermatic) vein, the ureter is isolated and incised. Then the cranial part of the ureter is used as a retractor exposing the renal hilum for dissection of the renal vessels. The main renal artery and vein are dissected separately by use of an endoscopic stapling device (Endo-GIA, white magazine). Finally, the kidney including Gerota's fascia is isolated from the adrenal and the upper peritoneum. Entrapment of the organ is performed with a specially designed bag (Lap-sac). The neck of the bag is brought out onto the surface of the abdomen (via port II/III) allowing digital morcellation with index finger inside the bag and removal of the organ in several pieces. We have applied this technique for 17 procedures in the upper retroperitoneum: 9 transperitoneal laparoscopic nephrectomies (TLN) for benign disease (5 hydronephrosis, 3 renovascular disease, 1 chronic pyelonephritis), 3 radical TLN including adrenalectomy for renal cell carcinoma (T2G2), 1 adrenalectomy for a cortical adrenaloma, 1 nephroureterectomy, 1 diagnostic ureterolysis and 2 modified retroperitoneal lymphadenectomies for stage I testicular cancer. The mean operation time was 4 h (2-5), the mean postoperative hospital stay 6 days (4-12).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenalectomy↗
PubMed1993

[Laparoscopic training in urology. An essential principle of laparoscopic interventions in the retroperitoneum].

The main problem with clinical introduction of laparoscopic techniques in urology is that despite experience with endoscopy no significant endoscopic training is given. Laparoscopic nephrectomy, in particular, is a rather complicated procedure and needs an adequate training concept: The beginner should have the possibility of practising in vitro in a closed "pelvi-trainer" to learn video-optical coordination and orientation; then it is necessary to get used to handling the instruments and practise the different steps of the procedure (i.e. clipping of vessels, sacking of the kidney) either in phantom models or in explanted animal organs. On this basis, we performed laparoscopic nephrectomy in an animal model (n = 18 porcine kidneys). We were able to standardize the technique of creating a pneumoperitoneum, the positioning of the animal, the site and size of the trocars, and preparation and clipping techniques (i.e. Endo-GIA) and entrapment of the kidney (testing different organ bags). A step-by-step approach was used for the introduction to clinical application. For simulation and training of video-assisted preparation techniques in patients and step-wise introduction to laparoscopy (instruments, endocoagulation, trocars), we created a "lap-tent", which was placed over the wound after exposition of Gerota's fascia. Further preparation was performed under laparoscopic conditions (without pneumoperitoneum) with a limited time allowed (1 h). Thereafter, we started with time-limited laparoscopy and laparoscopic lymphadenectomy prior to pelvic surgery (prostatectomy, cystectomy) to introduce the staff to the technique of pneumoperitoneum and placement of the trocars and to the use of the instruments in general. Based on this step-by-step training concept, after a 6-months period we were successful in introducing transperitoneal laparoscopic nephrectomy (TLN) to our clinical routine. So far, we have performed 20 laparoscopic nephrectomies, 1 nephro-ureterectomy, 4 tumour nephrectomies (inducing adrenalectomy), 2 adrenalectomies, and 6 modified retroperitoneal lymphadenectomies. In the lesser pelvis we have experience with 20 laparoscopic varicocelectomies, 23 pelvic lymphadenectomies, and 5 diagnostic laparoscopies for cryptorchidism (February 1993).

Adrenalectomy↗