Biomedical subjects

Jens Rassweiler

Publications and source records attributed to Jens Rassweiler.

9 recordsLinked to original sources

PubMed2003

Technical evolution of laparoscopic radical prostatectomy after 450 cases.

BACKGROUND AND PURPOSE: In 1998, laparoscopic radical prostatectomy with primary access to the seminal vesicles was introduced. In 1999, we developed a laparoscopic technique similar to the classic retropubic radical prostatectomy. We focus here on the continuous technical evolution of our technique. PATIENTS AND METHODS: From March 1999 to May 2002, we performed 450 laparoscopic radical prostatectomies. All important data of the patients; data concerning the performance of the procedure, including technical modifications, conversion, reintervention, and complication rate; as well as follow-up information were documented contemporaneously. The patients were divided into three groups of 150 individuals each in order to analyze the influence of the technical evolution of the procedure. Additionally, we studied the transferability of our technique, comparing the learning curves of the three surgeons involved in the program. RESULTS: The technical modifications included the routine use of a voice-controlled robot (AESOP) for the camera, exposure of the apex with 120 degrees retracting forceps, a free-hand suturing technique instead of the Endostitch device for the dorsal vein complex, 5-mm clipping instead of bipolar coagulation for the nerve-sparing technique, initial 6 o'clock suturing of the urethra before complete division, control of the prostatic pedicles by use of 12-mm Hemo-lok clips instead of the Ultracision or Endo-GIA, the bladder neck-sparing technique in cases of T(1c) and T(2a) tumors, and interrupted instead of continuous sutures for the vesicourethral anastomosis. All these modifications resulted in a significant decrease in operating time and the rates of transfusion, open conversion, and reintervention. The introduction of the nerve-sparing technique increased the number of tumor-positive margins. The mean operating time of the third surgeon was significantly less than that of the first surgeon, but the transfusion, conversion, and reintervention rates did not differ significantly among the surgeons. CONCLUSIONS: Laparoscopic radical prostatectomy has undergone continuous technical evolution resulting in a significant improvement of the operative results. Although we were able to demonstrate the transferability of this difficult procedure, we feel that it should be performed only at centers of expertise.

Adult↗

PubMed2003

Laparoscopic versus open radical prostatectomy: a comparative study at a single institution.

PURPOSE: There is an ongoing debate about the benefits of laparoscopic radical prostatectomy compared to the open retropubic approach. We compared the last 219 patients treated with open retropubic prostatectomy with 438 patients treated with laparoscopic radical prostatectomy at our institution, focusing on operative data, complications and mid-term outcome. MATERIALS AND METHODS: From December 1994 to November 1999 a total of 219 patients were treated with open prostatectomy and pelvic lymph node dissection (group 1). From March 1999 to September 2002, 219 patients underwent early (group 2) and 219 underwent late (group 3) laparoscopic radical prostatectomy and pelvic lymph node dissection. The same surgeons performed both operations. All 3 groups were similar with respect to mean patient age, mean prostate specific antigen value, median Gleason score, previous transurethral resection of the prostate and neoadjuvant treatment, although there was a slight stage shift in favor of the 2 laparoscopic groups. RESULTS: Mean operating time was significantly shorter after open surgery (196 minutes) compared to the early laparoscopic group (288) but it did not differ significantly from the late laparoscopic group (218). Mean blood loss (1,550 versus 1,100 versus 800 cc) and transfusion rates (55.7% versus 30.1% versus 9.6%) in groups 1 to 3 favored the laparoscopic groups. The complication rate in groups 1 to 3 was lower for laparoscopy (19.2% versus 13.7% versus 6.4%), but the spectrum differed. The early laparoscopic group had a higher incidence of rectal injuries (1.8% versus 3.2% versus 1.4% in groups 1 to 3, respectively) and urinary leakage (0.5% versus 2.3% versus 0.9%), whereas more lymphoceles (6.9% versus 0% versus 0%), wound infection (2.3% versus 0.5% versus 0%), embolism/pneumonia (2.3% versus 0.5% versus 0.5%) and anastomotic strictures (15.9% versus 6.4% versus 4.1%) occurred after open surgery. The amount of postoperative analgesia was significantly greater after open surgery (50.8 versus 33.8 versus 30.1 mg. in groups 1 to 3, respectively). Median catheter time was longer after open retropubic prostatectomy (12 versus 7 versus 7 days in groups 1 to 3, respectively) but the continence rates were similar in all 3 groups at 12 months (89.9% versus 90.3% versus 91.7%). The rate of positive margins did not differ significantly in groups 1 to 3 (28.2% versus 21.0% versus 23.2%), prostate specific antigen recurrence was equivalent related to the different observation periods. CONCLUSIONS: Laparoscopic radical prostatectomy is technically demanding, with an initially longer operative time, higher incidence of rectal injuries and urinary leakage. The overall outcome after 219 cases favors the laparoscopic approach. Consequently, at our institution laparoscopic radical prostatectomy has become the method of choice.

Adult↗

PubMed2003

Oncological safety of laparoscopic surgery for urological malignancy: experience with more than 1,000 operations.

PURPOSE: Although laparoscopy is being increasingly used to treat urological malignancies, there is still concern regarding the induction of local recurrence and port site metastasis. To our knowledge no major clinical study with long-term followup has been presented in the field of urological laparoscopy. We assessed the oncological safety of laparoscopy with emphasis on incidence of local recurrence and port site metastasis, analyzing the risk factors for such events based on a 10-year experience. MATERIALS AND METHODS: From June 1992 to May 2002 we performed 1,098 laparoscopic procedures for urological malignancies, including 450 radical prostatectomies, 478 pelvic and 80 retroperitoneal lymph node dissections, 45 radical nephrectomies, 22 radical nephroureterectomies, 12 partial nephrectomies and 11 adrenalectomies. In 418 cases of laparoscopic radical prostatectomy pelvic lymphadenectomy was done simultaneously. Of the procedures 917 were performed transperitoneally, including 181 via retroperitoneal or extraperitoneal access. A total of 567 procedures were performed in case of histologically proven cancer, whereas 531 represented only staging operations. RESULTS: Median followup was 58 months (range 4 to 127). Eight local recurrences were observed (0.73% overall, 1.41% of histologically proven cases). There were recurrences after nephroureterectomy for transitional cell carcinoma of the ureter in 1 patient, after radical nephrectomy for renal cell carcinoma in 1, growing teratoma after retroperitoneal lymph node dissection in 2, local recurrence of prostate cancer in 3 and after removal of an adrenal metastasis of melanoma in 1. Two port site metastases (0.18% overall, 0.35% of histologically proved cases) occurred, including metastasis of small cell lung carcinoma after adrenalectomy and a residual mass following 2 cycles of chemotherapy after retroperitoneal lymph node dissection. CONCLUSIONS: According to our experience the incidence of local recurrence and the risk of port site metastases is low and seems to be mainly related to the aggressiveness of the tumor and immunosuppression status of the patient, respectively rather than to technical aspects of the laparoscopic approach.

Adrenalectomy↗

PubMed2002

Laparoscopic versus open retroperitoneal lymph node dissection: a cost analysis.

PURPOSE: Laparoscopic retroperitoneal lymph node dissection is significantly less morbid than open retroperitoneal lymph node dissection but it is generally more costly due to longer operative time and disposable equipment. In response to budgetary pressure at our large county hospital we identified the cost components of laparoscopic retroperitoneal lymph node dissection that could be targeted to decrease procedure costs before expanding our laparoscopic retroperitoneal lymph node dissection program. MATERIALS AND METHODS: A comprehensive literature review of open and laparoscopic retroperitoneal lymph node dissection was performed and certain parameters were abstracted, including operative time and equipment, hospital stay, perioperative complications and surgical success rates. Using these data the projected overall cost and individual cost centers at our institution were compared for open and laparoscopic retroperitoneal lymph node dissection. Decision tree analysis models were devised to estimate the cost of each treatment using commercially available software. We performed 1 and 2-way sensitivity analysis to evaluate the effect of individual treatment variables on overall cost. Base case analysis involved a young man with clinical stage I nonseminomatous testicular cancer who was a candidate for retroperitoneal lymph node dissection. RESULTS: Based on a review of the costs at our institution open retroperitoneal lymph node dissection was a less costly procedure at $7,162 versus $7,804 for the laparoscopic approach. The slight cost superiority of the open approach was due to significantly lower costs associated with operating room time and equipment. On the other hand, the laparoscopic procedure showed a cost advantage for hospital stay. On 1-way sensitivity analysis laparoscopic dissection was less costly when operative time was less than 3.6 hours, hospitalization was less than 2.2 days or laparoscopic equipment costs were less than $768. On 2-way sensitivity analysis the laparoscopic approach was cost advantageous when performed in less than 5 hours or when the patient was discharged home within 2 days postoperatively. CONCLUSIONS: The primary cost variables for surgical treatment for testicular cancer include operative time, hospital stay and equipment cost. According to published data and decision tree analysis open retroperitoneal lymph node dissection is slightly less costly (less than $650) than laparoscopic retroperitoneal lymph node dissection for the surgical treatment of clinical stage I nonseminomatous testicular cancer at our institution. Our model identifies several measures that can be applied at any institution to render laparoscopic retroperitoneal lymph node dissection economically superior to the open approach.

Adult↗

PubMed2002

Current laparoscopic practice patterns in urology: results of a survey among urologists in Germany and Switzerland.

OBJECTIVES: A survey was performed to assess the current practice patterns in laparoscopy among urologists in Germany and Switzerland. METHODS: Using the database directory of the German and Swiss Urological Association urological departments were identified. A detailed questionnaire was designed and sent by postal service. Responding questionnaires were analyzed. RESULTS: The overall response rate was 64%. Fifty-four percent of respondents in Germany and 33% in Switzerland already perform laparoscopy; another 50% and 56% are planning to introduce laparoscopy. Thirty-six percent think that laparoscopy is economical and 77% await shortening of hospital stay. Major concerns are: Economical aspects, lengthy learning curve, investment, and lack of scientific data. The number of laparoscopic procedures during 12 months was registered for 19 indications. More than 40 procedures for one indication are performed by only 6% of the departments. CONCLUSIONS: The survey reveals an increasing number of departments performing laparoscopy and broad acceptance of the technology but combined with some major concerns. Currently only a minority of the departments perform more than 40 procedures for one indication suggesting that at present laparoscopy is mainly a center-based technology.

Data Collection↗

PubMed2002

Simulators and endourological training.

Acquisition of skills laboratory training seems to be of importance in the training of surgeons, and is intended to cover the gap between theoretical learning and real practice. Economic and ethical reasons limit the use of animals during the learning process, while trends in medical change have severely restricted the available time to teach and to learn. With the incorporation of laparoscopy and the blossoming of minimally invasive techniques, mainly endoscopy, simulators have gained wide acceptance as an important tool in the surgeon's learning process. Two types of simulators are currently available: inanimates or mannequins and virtual reality simulators. A review of the recent literature shows that there is generally a significant improvement in dexterity after using simulators, whichever type is used. It is still unknown whether training simulation influences the patient's outcome positively.

Clinical Competence↗

PubMed2002

Transurethral resection for bladder cancer using 5-aminolevulinic acid induced fluorescence endoscopy versus white light endoscopy.

PURPOSE: Endoscopy done under fluorescence induced by 5-aminolevulinic acid has proved to be a procedure with high sensitivity for detecting transitional cell carcinoma of the bladder. In this multicenter, parallel group, phase III study we compared 5-aminolevulinic acid fluorescence endoscopy guided transurethral bladder resection with transurethral bladder resection done using only white light endoscopy. The proportion of tumor-free resected cases in the 2 groups was evaluated. MATERIALS AND METHODS: After patient stratification according to participating centers and European Organization for the Research and Treatment of Cancer risk score 65 and 64 were randomized to the 5-aminolevulinic acid fluorescence and white light endoscopy groups, respectively. Residual tumor was evaluated in the 2 groups by repeat transurethral resection 10 to 14 days later. Analysis was performed according to the intent to treat principle with all patients randomized, followed by per protocol analysis. RESULTS: Intent to treat analysis revealed that in the white light endoscopy group 40.6% of cases were resected tumor-free at primary resection, whereas with 5-aminolevulinic acid fluorescence endoscopy guided transurethral resection 61.5% were resected tumor-free (p <0014). On protocol analysis 46.9% patients in the white light and 67.3% in the 5-aminolevulinic acid fluorescence endoscopy groups were resected tumor-free (p <0.031). No difference was noted in the 2 groups in regard to side effects or laboratory findings. CONCLUSIONS: The risk of residual tumor after transurethral resection of transitional cell carcinoma is significantly decreased by 5-aminolevulinic acid fluorescence endoscopy.

Adult↗

PubMedDate not supplied

Laparoscopic radical prostatectomy: a European virus with global potentials.

OBJECTIVES: To review the current status of the Laparoscopic Radical Prostatectomy in Europe (LRP). METHODS: The published peer reviewed articles on the experience of the European groups performing Laparoscopic Radical Prostatectomy. RESULTS: Three different approaches have been described for LRP, two of them transperitoneally (early dissection of seminal vesicles or of the prostatic apex) and one totally extra peritoneally. Results in terms of per operative performances and immediate outcomes seem to be comparable with the exception of the bleeding and the transfusion rate that seem higher in the transperitoneal approach with early dissection of the prostatic apex. Conversion rates have been described up to 5% but it is rare after the 20 first cases; after the learning curve has been overcome the complication rate varies between 10% and 17%. Being a novel technique, all the series have a short median follow-up of around one year. The one-year continence rates are comparable to the ones described with the classical open approach, as it is the potency rate. The rate of positive margins bounces between 2 and 49% depending mainly on case selection. A long and steady learning curve burdens the technique in terms of complications. CONCLUSIONS: LRP is feasible, teachable and reproducible. Although no comparative series with the open approach are available yet, functional and oncological results seem to be comparable to the ones reached after open Retropubic Radical Prostatectomy.

Adenocarcinoma↗

PubMedDate not supplied

Robotics, telesurgery and telementoring--their position in modern urological laparoscopy.

OBJECTIVES: Laparoscopic surgery in general is handicapped by the reduction of the range of motion from six to four degrees of freedom. This has a major impact on technically difficult procedures such as laparoscopic radical prostatectomy. Solutions for this problems include the understanding of the geometry of laparoscopy with sophisticated training programs, but lie also in newly developed surgical robots, computer simulators and telementoring. This article evaluates the value of these alternatives based on own experiences and an analysis of the current literature. METHODS: Own experiences with robot-assisted surgery include 406 laparoscopic radical prostatectomies using a voice-controlled camera-arm (AESOP) as well as 6 telesurgical interventions with the Da Vinci-system. Additionally, substantial experimental studies have been performed focussing on the geometry of laparoscopy and new training concepts such as perfused pelvitrainers and computer simulation. Moreover, the current literature of the last 10 years on telesurgery and telementoring has been reviewed. RESULTS: 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 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 to 110 degrees. 3-D-systems did 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 (ZEUS, Da Vinci) in clinical use for telesurgery, of which only the Da Vinci provides stereovision and all six degrees of freedom (DOF). In the meantime, more than 200 laparoscopic radical prostatectomies have been performed with this system. Until now, 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 enabling to realize telemanipulation and telementoring over long distances (i.e. transatlantic). CONCLUSION: 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. Whereas there will be a clear role of audio-visual telementoring in future training concepts, the need of telemanipulation/telesurgery has not yet been clarified. New technological concepts promote the development of hand-held mechanical manipulators (i.e. 6-DOF-needle-holder) used in combination with mono-tasking computerized robots (i.e. AESOP) resulting in a significant cost reduction.

Computer Simulation↗