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The Journal of Urology | 1998

RETROPERITONEOSCOPY: EXPERIENCE WITH 200 CASES

Jens Rassweiler; O. Seemann; Thomas Frede; Thomas Oliver Henkel; Peter Alken

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.


The Journal of Urology | 1996

Laparoscopic Retroperitoneal Lymph Node Dissection for Nonseminomatous Germ Cell Tumors: Indications and Limitations

Jens Rassweiler; O. Seemann; Thomas Oliver Henkel; Christian Stock; Thomas Frede; Peter Alken

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).


European Urology | 2000

Long–Term Experience with Laparoscopic Retroperitoneal Lymph Node Dissection in the Management of Low–Stage Testis Cancer

Jens Rassweiler; Thomas Frede; E. Lenz; O. Seemann; Peter Alken

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.


Minimally Invasive Therapy & Allied Technologies | 2001

Telepresence surgery: first experiences with laparoscopic radical prostatectomy

Jens Rassweiler; Thomas Frede; O. Seemann; Christian Stock; L. Sentker

The concept of an intelligent steerable surgical instrument system has been described by various authors. Since 1998, telesurgical minimally invasive procedures have been performed with the da Vinci system, mainly for cardiac bypass surgery. We present our initial experience using the device for robot-assisted laparoscopic radical prostatectomy. 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 manoeuvres detachable surgical instruments. These instruments are introduced via two 8 mm trocars and allow movements in all six degrees of freedom (DoF). The surgeon performs the procedure while seated at the console holding specially designed instruments. Highly specialised computer software and mechanics transmit the surgeon‘s hand movements exactly to the microsurgical movements of the manipulators at the operative site. The system used is a W-shaped five trocar arrangement, with the robot‘s arms at the lateral trocars (8 mm) and two assistant trocars medially (10 mm). A sixth trocar was used in the right suprapubic area for retraction of the gland (Foley catheter). The left assistant used different instruments, such as bipolar forceps, Ultracision, and Endoclip, wheras the right assistant mainly used the suction–irrigation device. The Intuitive System was attached after trocar placement and exposure of Retzius‘ space. We treated six patients (two pT2, four pT3, median Gleason score 6). The operating room time averaged 315 (range 242–480) min, including pelvic lymph-node dissection. No intra-operative complications occured, one patient required transfusions. There were no positive margins, median catheter time was 5 days. Three patients were completely continent after 1 month. Telerobotic laparoscopic radical prostatectomy is feasible. There is a learning curve with the device, mainly due to the magnification, 3D image and lack of tactile feedback. However, the experienced surgeon can become familiar with the device after a short time. There is still a need for further development of instruments for urological procedures.


Chirurg | 1998

Retroperitoneoskopie – Erfahrungen mit den ersten 200 Fällen

Jens Rassweiler; Thomas Frede; O. Seemann

Summary. 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.Zusammenfassung. Der retroperitoneale Zugang findet breite Anwendung bei offenen Operationen in der Urologie. Mit Einführung der Ballondissektionstechnik konnte dieser anatomische Zugang auch für laparoskopische Operationen genutzt werden. Material und Methode: Zwischen 12/1992 und 10/1997 wurden 200 retroperitoneale Operationen an 197 Patienten (Alter 4–82 Jahre) durchgeführt: 78 Nephrektomien, 50 Nierencystenresektionen, 14 Nephropexien, 11 Ureterolysen, 8 retroperitoneale Lymphadenektomien, 8 Nierenbiopsien, 6 Adrenalektomien, 6 Heminephrektomien, 6 Pyeloplastiken, 5 Ureterolithotomien, 6 Ureterocutaneostomien sowie 2 andere. 38 Patienten (19 %) waren bereits abdominell , 22 (11 %) an Niere und Ureter voroperiert. Die Präparation des Retroperitonealraums erfolgte in 14 Fällen mit Hilfe eines Ballonkatheters, in 93 Fällen mittels eines Ballontrokarsystems, während in den letzten 93 Fällen eine Präparation des Retroperitoneums mit dem Zeigefinger sich als ausreichend erwies. Ergebnisse: Die Eingriffe wurden wie folgt klassifiziert: 76 einfache Operationen (z. B. Nierenbiopsie, Nierencystenresektion, Ureterocutaneostomie), 102 schwierige (z. B. Adrenalektomie, Nephrektomie, Nephropexie) und 22 sehr schwierige Eingriffe (z. B. Pyeloplastik, Heminephrektomie, Lymphadenektomie). Während der ersten 50 Fälle zeigte sich eine signifikante Lernkurve, welche sich in einer höheren Operationszeit und Komplikations- sowie Konversionsrate widerspiegelte. Abhängig vom Schwierigkeitsgrad des Eingriffs betrugen die mittlere Operationszeiten 45–100 min bei leichten Eingriffen, 95–185 min bei schwierigen und 185–240 min bei sehr schwierigen Operationen. In den letzten 50 Fällen war die Komplikations-, Konversions- sowie Reinterventionsrate mit offenen Eingriffen vergleichbar (2, 4 und 2 %). Schlußfolgerung: Nach mehr als 200 retroperitoneoskopischen Eingriffen wurde die Zugangstechnik bedeutend vereinfacht, so daß das Verfahren heute standardisiert, sicher und reproduzierbar ist.


Journal of Endourology | 1998

Organ Retrieval Systems for Endoscopic Nephrectomy: A Comparative Study

Jens Rassweiler; Christian Stock; Thomas Frede; O. Seemann; Peter Alken


Journal of Endourology | 1997

Laparoscopy-Assisted Penile Revascularization: A New Method

M. Hatzinger; O. Seemann; L. Grenacher; Jens Rassweiler


Der Urologe B | 2000

Die laparoskopische Kolposuspension nach Burch Fakt und Fiktion

Jens Rassweiler; Thomas Frede; O. Seemann; T. Jaeger


Atlas of The Urologic Clinics | 1999

Laparoscopic Radical Retroperitoneal Lymph Node Dissection for Low-Stage Testis Cancer

Jens Rassweiler; Thomas Frede; Elke Lenz; O. Seemann; Peter Alken


Der Urologe B | 2000

Die laparoskopische Kolposuspension nach Burch

Jens Rassweiler; Thomas Frede; O. Seemann; Thomas V. Jaeger

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Thomas Frede

Université libre de Bruxelles

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Thomas Frede

Université libre de Bruxelles

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Christian Stock

German Cancer Research Center

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E. Lenz

Heidelberg University

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Elke Lenz

Heidelberg University

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