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R Peschel

Publications and source records attributed to R Peschel.

At least 37 records · Page 2Linked to original sources
PubMed1998

Laparoscopic surgery for pheochromocytoma: adrenalectomy, partial resection, excision of paragangliomas.

PURPOSE: Surgical treatment of pheochromocytoma includes adrenalectomy, adrenal sparing surgery and excision of extraadrenal paragangliomas. We report our experience using laparoscopy for these procedures. MATERIALS AND METHODS: Between June 1992 and November 1997, 19 patients underwent laparoscopic surgery for pheochromocytoma. Of the patients 14 had solitary tumors, and 4 presented with bilateral pheochromocytomas and 1 or 2 additional paragangliomas. In 1 patient a recurrent pheochromocytoma was found in the contralateral adrenal following previous right adrenalectomy. One patient each had myocardiopathy, amaurosis and stroke secondary to severe hypertension. Two patients were pregnant. RESULTS: All solitary tumors were treated with laparoscopic adrenalectomy. Laparoscopic adrenal sparing surgery (4 cases, 2 bilateral) and bilateral adrenalectomy (1) were performed for multiple familial pheochromocytoma, and all paragangliomas were excised simultaneously. The pregnant patients underwent surgery at 16 and 20 weeks of gestation, respectively. All procedures were completed as planned. The rate of minor intraoperative and postoperative complications was 11% and 16%, respectively, and there were no major complications. In all patients the catecholamine levels returned to normal and no residual tumors were found at followup. None of the patients undergoing partial resection required steroid replacement therapy. CONCLUSIONS: In experienced hands, laparoscopic surgery for solitary and multiple pheochromocytoma and paraganglioma is feasible and safe, and does not increase the specific risks associated with pheochromocytoma surgery.

Adrenal Gland Neoplasms↗
PubMed1998

Correlation of medical dosimetry quality indicators to the local tumor control in patients with prostate cancer treated with iodine-125 interstitial implants.

The treatment of prostate cancer by 125I interstitial implants has been extensively studied with mixed results by one institution or another. A recent study from Hahnemann [Int. J. Radiat. Oncol., Biol., Phys. 21,955-960 (1991)] reported results that were extremely poor compared to those reported in an earlier study at Yale [Int. J. Radiat. Oncol., Biol., Phys. 14, 1153-1157 (1988)] or those in an Eastern Virginia Study [Cancer 63, 2415-2420 (1989)]; differences in 5-yr survival rates being more than a factor of 2. Such large discrepancies from institution to institution led us to a reexamination of the dosimetry. This study analyzed quantitatively three-dimensional dosimetric parameters of 110 prostate cancer patients treated with 125I interstitial implants. The study searched for "cutoff" values in each parameter that divided the patients into two groups with statistically significant differences in the local recurrence-free survival rates. A comparison of the three-dimensional isodose surfaces of patients with favorable values in all of the parameters to those patients with all unfavorable parameters show how these characteristics translated into poor dose coverage and much inhomogeneity within the implant even for cases that met the traditional criteria for adequacy (160 Gy to the tumor volume). Patients in the favorable group had 10-yr survival rates higher by a factor of up to 2 compared to those in the unfavorable group. The strong correlation of three-dimensional volume-dose parameters to the local control rate observed in this study further emphasizes how important it is to assess the three-dimensional dosimetric adequacy of interstitial implants before deciding on their clinical efficacy. If implants are performed with appropriate attention to dosimetry parameters, excellent clinical results are obtained. On the other hand, if dosimetry parameters are not correct, the implant results can be poor.

Adenocarcinoma↗
PubMed1998

Laparoscopic nephron sparing surgery for small renal cell carcinoma.

PURPOSE: In recent years the detection rate for small renal tumors has increased due to the widespread use of advanced diagnostic imaging techniques, which in turn has increased the need for nephron sparing surgery. We investigate whether laparoscopic surgery is a suitable approach to partial resection of small renal tumors. MATERIALS AND METHODS: Between June 1994 and October 1996, 7 patients underwent laparoscopic wedge resection of the kidney for renal tumors up to 2 cm. in diameter. Hemostasis was achieved mainly by bipolar coagulation. In addition, the resection surface was cauterized with an argon beam coagulator and then sealed with fibrin glue. In 1 procedure a novel ultrasonic dissector was tested. RESULTS: All procedures could be completed as planned. The only intraoperative complication was a pneumothorax that resolved spontaneously within 2 days. There were no postoperative complications. Histological examination yielded stage pT1 grade I renal cell carcinoma in 3, stage pT1 grade II in 2 and multilocular cysts in 2 cases. All patients had negative surgical margins. Postoperatively, renal function as assessed by serum creatinine was unchanged. Neither local recurrences nor metastases were observed during a followup of 7 to 35 months. CONCLUSIONS: Our results indicate that laparoscopic partial nephrectomy is feasible for small renal cell carcinoma, and is associated with low morbidity and a low complication rate.

Adult↗
PubMed1997

New onset hypertension after extracorporeal shock wave lithotripsy: age related incidence and prediction by intrarenal resistive index.

PURPOSE: In a recent study we found an increased resistive index immediately after extracorporeal shock wave lithotripsy (ESWL) in patients older than 60 years, which suggests renovascular disturbance. The present 26-month followup study was undertaken to investigate the relevance of elevated resistive index levels and the incidence of new onset hypertension. MATERIALS AND METHODS: Of the initial 76 patients 57, including 20 of the 23 at risk patients 60 or greater years, group 3), were followed for more than 26 +/- 6 months after ESWL. Followup included 2 resistive index measurements by Doppler ultrasound of the treated and the contralateral kidney, at least 2 blood pressure measurements 1 week apart and excretory urography as well as determination of plasma renin activity in 9 patients. RESULTS: With 1 exception, elevated resistive index levels and hypertension were observed exclusively in patients older than 60 years. In these patients the resistive index ranged between 0.65 and 0.86 (mean plus or minus standard deviation 0.74 +/- 0.05, normal less than 0.7). This increase in resistive index was statistically significant (p < 0.0001). Compared to the levels obtained immediately after ESWL, the resistive index continued to increase in all 9 patients older than 60 years who had hypertension (45%), whereas in the normotensive patients the resistive index was either stable or decreased. There was a strong positive correlation (0.903) between pathological resistive index levels and blood pressure. CONCLUSIONS: Patients older than 60 years are at risk for disturbances of renal perfusion as assessed by the resistive index, and 45% of these patients have new onset hypertension within 26 months of treatment.

Adolescent↗
PubMed1996

Laparoscopic and retroperitoneoscopic repair of ureteropelvic junction obstruction.

OBJECTIVES: The aim of this study was to evaluate laparoscopic and retroperitoneoscopic pyeloplasty and to compare the efficacy of dismembered and nondismembered techniques. METHODS: Since May 1993, a modified laparoscopic transperitoneal (14 patients) and a retroperitoneoscopic approach (3 patients) have been used for the management of ureteropelvic junction obstruction. In 7 patients aberrant vessels were encountered; 1 patient had a horseshoe kidney. Surgical repair was achieved by dismembered pyeloplasty (8 patients), nondismembered Fenger-plasty (longitudinal incision, transverse closure; 3 patients), transaction and reanastomosis of the renal pelvis (1 patient), ureterolysis and displacement of crossing vessels (4 patients). RESULTS: In 1 patient dismembered pyeloplasty could not be scheduled because of cardiovascular problems. A minimal transient lesion of the sympathetic nerve was observed postoperatively in 1 patient and pulmonary embolism in another. The operative time in dismembered pyeloplasty was between 240 and 360 minutes (mean, 280); the results were good in all patients. Equally good results were obtained with nondismembered Fenger-plasty, and the operating time was shorter (120 to 180 minutes). Ureterolysis was found to have a failure rate of 50%. CONCLUSIONS: Laparoscopic dismembered pyeloplasty yielded good results but it is too complicated to become a standard procedure. Nondismembered Fenger-plasty, which also showed good results, is more suitable for laparoscopy and retroperitoneoscopy. The indications for this technique should be defined more precisely as more experience is being collected. The results of ureterolysis when used as a single measure were poor, and, therefore, this technique should be abandoned.

Adolescent↗
PubMed1996

[Laparoscopic spermatic vein ligation].

Between December 1991 and November 1995 a total of 231 patients underwent laparoscopic varix ligation in our department. The laparoscopic varicocelectomy offers a lower rate of morbidity, allows for microscopic dissection with preservation of the spermatic artery and is amenable to bilateral ligation without a second incision. The spermatic arteries were identified by using a laparoscopic vascular Doppler probe. Any laparoscopic procedure carries some risk of injury to intra-abdominal organs when placing the primary trocar. Therefore, a new extraperitoneal approach has been developed to avoid these risks.

Adult↗
PubMed1996

[Laparoscopic and retroperitoneoscopic kidney pyeloplasty].

The aim of this study was to evaluate laparoscopic and retroperitoneoscopic pyeloplasty and to compare the efficacy of dismembered and non-dismembered techniques. Between April 1993 and December 1995 a modified laparoscopic transperitoneal (18 patients) and a retroperitoneoscopic approach (3 patients) were used for the management of ureteropelvic junction obstruction. In 11 patients aberrant vessels were encountered; one patient had a horse-shoe kidney. Surgical repair was achieved by dismembered pyeloplasty (8 patients), non-dismembered Fenger-plasty (longitudinal incision-transverse closure: 7 patients), transection and reanastomosis of the renal pelvis (1 patient), ureterolysis and displacement of ventrally crossing vessels (4 patients). In one patient dismembered pyeloplasty could not be scheduled because of cardiovascular problems. A minimal transient lesion of the sympathetic nerve was observed postoperatively in one patient and pulmonary embolism in another. The operative time in dismembered pyeloplasty was between 240 and 360 min (mean 280); the results were good in all patients. Equally good results were obtained with non-dismembered Fenger-plasty, and the operating time was shorter (120-180 min). Ureterolysis was found to have a failure rate of 50%. Laparoscopic dismembered pyeloplasty yielded good results, but it is too complicated to become a standard procedure. Non-dismembered Fenger-plasty, which also showed good results, is more suitable for laparoscopy and retroperitoneoscopy. The indications for this technique should be defined more precisely as more experience is collected. The results of ureterolysis-when used as a single measure-were poor, and therefore this technique should be abandoned.

Adolescent↗
PubMed1995

Diagnostic laparoscopic retroperitoneal lymph node dissection for non seminomatous testicular tumor.

Retroperitoneal lymph node dissection for nonseminomatous testicular tumor. A modified retroperitoneal lymph node dissection for stage I testicular tumor has been described by Weissbach. We have developed a two-step procedure for performing laparoscopic retroperitoneal lymph-adenectomy within these boundaries. In the first step, a ventral approach is used. The colon is dissected free, then the spermatic vein is excised, and the borders of the dissection are defined. Removal of retroaortic and retrocaval nodal tissue is technically not feasible via the ventral approach. Therefore, in the second step, a lateral approach is employed, which is the key to success since it permits easy transection of the lumbar vessels. Thus complete lymph node dissection can be achieved. Between August 1992 and March 1994 this procedure was performed in 15 patients. In nine patients, the tumor was on the right side and in six on the left. Conversion to open surgery was necessary in two patients because of uncontrollable bleeding and a large metastasis, respectively. Microscopic metastases were detected in two other patients. Apart from the above-mentioned bleeding no major complications occurred; no blood transfusion were required. The results obtained so far demonstrate that this procedure is technically feasible. Therefore, we have decided to perform laparoscopic retroperitoneal lymphadenectomy also in patients with stage II B tumors who have received chemotherapy; to date one patient with a left-sided stage II B tumor has been operated on successfully.

Adult↗
PubMed1994

Laparoscopic retroperitoneal lymph node dissection for clinical stage I nonseminomatous testicular tumor.

OBJECTIVES: An appropriate laparoscopic technique for diagnostic retroperitoneal lymph node dissection in clinical Stage I testicular tumors is presented and its efficiency and morbidity are evaluated. METHODS: A two-step procedure has been developed. In the first step, a ventral approach is used. The colon is dissected free, then the spermatic vein is excised and the borders of dissection are defined. Via the ventral approach removal of retroaortic and retrocaval nodal tissue is technically not feasible. Therefore, in the second step, a lateral approach is used, which is the key to success because it permits straightforward transection of the lumbar vessels. Thus, complete lymph node dissection within the boundaries described by Weissbach can be achieved. Between August 1992 and March 1994, this procedure was performed in 15 patients. In 9 patients, the tumor was on the right side and in 6 it was on the left. RESULTS: Conversion to open surgery was necessary in 2 patients because of uncontrollable bleeding and a large metastasis. Microscopic metastasis were detected in 2 other patients. Apart from the bleeding just mentioned, no major complications occurred; no blood transfusions were required. CONCLUSIONS: The results obtained so far demonstrate that the technique is feasible and decreases postoperative morbidity. It therefore warrants further consideration.

Adult↗
PubMed1994

[Laparoscopic interventions in pediatric urology].

Between January 1992 and June 1993 a total of 36 children underwent laparoscopic surgery in our department. On account of its superior validity, diagnostic laparoscopic surgery for nonpalpable testicles has become a viable alternative to the currently available imaging techniques. Furthermore, diagnostic laparoscopy has the benefit of enabling the surgeon to proceed directly with adequate therapy. Our results gained in 29 pediatric laparoscopic procedures for varicoceles show that it is a very efficient technique that entails few complications. The varicocele persisted in only 1 of the 29 children. In 2 patients laparoscopic nephrectomy was performed, which in technical terms turned out to be less complicated than in adults. Postoperatively, 1 patient developed an incarcerated hernia at the site of trocar insertion. In 2 patients a laparoscopic Lich-Gregoir procedure was performed for vesicoureteral reflux, which, however, cannot yet be considered a viable alternative to the conventional operative techniques.

Adolescent↗
PubMed1994

[Laparoscopic retroperitoneal lymph node excision in clinical stage I non-seminomatous testicular cancer].

Modified retroperitoneal lymph node dissection for stage I testicular tumors has been described by Weissbach. For performing laparoscopic retroperitoneal lymphadenectomy within these boundaries, we have developed a two-step procedure. In the first step, a ventral approach is used. The colon is dissected free, then the spermatic vein is excised, and the borders of dissection are defined. Removal of retroaortic and retrocaval nodal tissue is technically not feasible from the ventral approach. Therefore, in the second step, a lateral approach is employed, which is the key to success since it allows for easy transection of the lumbar vessels. Thus complete lymph node dissection can be realized. Between August 1992 and June 1993 this procedure was performed in 11 patients. In 7 patients, the tumor was on the right side and in 4 on the left. Conversion to open surgery was necessary in two patients because of uncontrollable bleeding and a large metastasis, respectively. Microscopic metastases were detected in two other patients. No major complications occurred; no blood transfusions were required. So far, the results have been encouraging.

Adult↗
PubMed1993

Laparoscopic retroperitoneal lymphadenectomy in the pig: initial report.

The value of retroperitoneal lymphadenectomy in the management of nonseminomatous testicular tumors is still a matter of controversy. Lymphadenectomy doubtlessly has great advantages but is somewhat down-graded by the considerable associated morbidity. Our experimental study in six pigs has shown that retroperitoneal lymphadenectomy by means of laparoscopic techniques is feasible. Clinical trials will follow. Should they prove successful, the role of retroperitoneal lymphadenectomy in the management of testicular tumors has to be reassessed.

Animals↗
PubMed1993

Left-sided laparoscopic adrenalectomy.

Laparoscopic transperitoneal adrenalectomy was performed in a 42-year-old female with a left adrenocortical adenoma causing Conn's syndrome. No technical problems occurred during surgery and the patient recovered quickly.

Adrenal Cortex Neoplasms↗
PubMed1991

A dosimetric analysis of Morris, Fletcher, and Henschke systems for treatment of uterine cervix carcinoma.

The role of intracavitary irradiation in the treatment of uterine cervix carcinoma is well established, and over the years a number of different systems for intracavitary irradiation have been developed. To compare the clinical efficacy of different systems and to develop guidelines for the design of applicators with new sources such as americium-241, we present a dosimetric comparison of three systems: (a) the Morris system, a modified Stockholm technique; (b) the Henschke system; and (c) the Fletcher system. Using a computerized planning system, dose distributions with different configurations of each system were calculated. For each case, doses to point A, B, and a set of reference points representing bladder and rectum were also calculated. Also, the 60 Gy reference volumes, as defined by ICRU Report No. 38, 1985, were calculated for six different treatment regimens. These treatment regimens employ widely different combinations of whole pelvis external beam dose, split pelvis external beam dose, and intracavitary irradiation dose to achieve similar clinical outcomes for the treatment of various stages of cervix carcinoma. From this analysis we observe the following: (a) The Morris system produces a higher dose rate to point A (70 to 90 cGy/hr) compared to the Fletcher or Henschke system (50 to 70 cGy/hr); (b) the doses to point B relative to point A dose are about the same for all three systems at 28 to 32%; (c) the doses to reference rectum and bladder points relative to point A dose for clinically equivalent configurations are about the same for Fletcher and Henschke systems (58-65%) not including the effects of shields in the vaginal ovoids, and somewhat higher for the Morris system (72-79%); (d) the volume treated to a given dose rate by each intracavitary system alone is about the same; and (e) the 60 Gy volume depends critically upon the external beam whole pelvis dose, rising steeply as the external beam whole pelvis dose approaches 30 Gy. Since different groups have used widely different prescriptions of external beam whole pelvis dose, ranging from 0 to 50 Gy depending upon stage, the 60 Gy volumes for these various dose prescriptions are strikingly different. Because the Morris system uses lower values for the external beam whole pelvis dose than the others, its 60 Gy volume for the advanced Stage IIB and IIIB is 2 to 4 times lower than others. This choice makes the Morris system more conservative than others, probably resulting in slightly lower cure rates for the advanced stage disease.

Brachytherapy↗