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Raymond J Leveillee

Publications and source records attributed to Raymond J Leveillee.

At least 19 recordsLinked to original sources
PubMed2006

Frequency of ureteroscope damage seen at a tertiary care center.

PURPOSE: There is controversy regarding ureteroscope durability. Little is known regarding the subsequent durability of a flexible ureteroscope after major damage has been incurred and the ureteroscope has been repaired. Maintenance and repair are associated with significant cost. We reviewed and assessed the frequency and cause of ureteroscope damage at our medical center. MATERIALS AND METHODS: From December 2001 we prospectively recorded the specific use of all ureteroscopes and any resultant damage at a single tertiary care institution. We then reviewed a total of 601 ureteroscopic cases involving 654 semirigid and flexible ureteroscope uses from December 2001 to November 2004. Cases were performed by multiple residents and fellows under the supervision of 3 attending urologists (CML, RJL and VGB). Retrograde and antegrade cases involving stones, urothelial carcinoma, strictures and diagnostic evaluations were included. Repairs for the respective ureteroscopes were performed by the original manufacturer. RESULTS: A total of 53 reports of damage (8.1% of total uses) were recorded. Major damage when the scope was deemed unusable and required repair was seen in 39 cases (6.0%). Four newly purchased flexible ureteroscopes were entered into the study and they provided 40 to 48 uses before the initial repair was needed. After these new ureteroscopes underwent comprehensive repair for major damage they averaged only 11.1 uses (median 8) before needing repair again. Older model ureteroscopes that underwent repair before being entered into our study averaged between 4.75 and 7.7 uses before being sent for subsequent repair. Of the total of 39 breakages 39 for which ureteroscopes were sent for repair 14 (35.9%) were the result of errant laser firing, 11 (28.2%) were the result of excessive torque, 8 (20.5% 8) were the result of decreased flexion in the distal tip or another loss of function without obvious iatrogenic cause, 3 (7.7%) were the result of multifocal catastrophic damage involving laser firing and excessive torque, and 3 (7.7%) were the result of cleaning and processing outside of the ureteroscopy suite. CONCLUSIONS: The most important risk factors for predicting the number of uses expected from a ureteroscope at our institution is ureteroscope age and whether the ureteroscope has undergone comprehensive repair as the result of prior damage. Our analysis suggests that after damage occurs to a ureteroscope more damage occurs with greater frequency. The cost of maintaining previously used ureteroscopes should be carefully considered in comparison to the cost of purchasing a new ureteroscope.

Equipment Failure↗
PubMed2006

Combining hand assisted laparoscopic nephroureterectomy with cystoscopic circumferential excision of the distal ureter without primary closure of the bladder cuff--is it safe?

PURPOSE: We have previously described our technique of combining HAL-NU using early ureteral ligation with simultaneous cystoscopic circumferential excision of the distal intramural ureter without primary closure of the bladder cuff. We report the oncological sequelae in patients who underwent HAL-NU using our technique of complete ureteral removal. MATERIALS AND METHODS: We retrospectively evaluated all patients who underwent HAL-NU from April 1999 through July 2004. Cystograms were performed 1 week postoperatively in all patients. Pathological findings were reviewed. Cystoscopy was performed every 3 months to assess bladder recurrences. Upper tract imaging was performed postoperatively and then annually. The locations of recurrence and need for adjuvant treatment were assessed. RESULTS: A total of 49 patients with an average age of 67 years underwent HAL-NU. Gravity cystography confirmed that bladder defects had completely sealed at 1 week in all patients. Mean followup was 10.6 months (median 10, range 1 to 52). Of the patients 20 (49%) had bladder tumors postoperatively. Two patients were found to have advanced stage disease, leading to chemotherapy with radiation therapy in 1 and radical cystectomy in the other at 4 and 14 months, respectively. A total of 25 patients had postoperative pelvic imaging. Four patients with pathological stage T2 (1) and T3 (3) had metastatic disease at followup. One patient was known to have pulmonary metastases preoperatively and HAL-NU was performed for refractory hematuria. Two patients were noted to have distant metastases to the liver, lung and bone at 1 and 3 months postoperatively, respectively. One patient was found to have distant metastases to the liver and retroperitoneal lymph nodes 2 years after surgery. No patients were found to have local pelvic or peritoneal metastases. CONCLUSIONS: HAL-NU with cystoscopic excision of the distal ureter is feasible, safe and effective for upper tract transitional cell carcinoma. Oncological sequelae are comparable to results after open surgery. There is no evidence to suggest pelvic or peritoneal tumor seeding since no cases of pelvic or abdominal recurrence were discovered after surgery, while allowing the bladder defect to close spontaneously with catheter drainage. Our technique of ureterectomy ensures complete removal of the entire ureter, eliminating the possibility of ureteral stump recurrences. Early ligation of the ureter prevents tumor migration during renal manipulation, minimizing the risk of local tumor recurrences postoperatively.

Adult↗
PubMed2005

Hand-assisted laparoscopic removal of retroperitoneal liposarcoma.

Liposarcoma is known to be the most common soft-tissue sarcoma, and the treatment of retroperitoneal disease is surgical excision. We present a case of complete surgical removal with concomitant nephrectomy using a hand-assisted laparoscopic approach and provide a review of the published studies.

Aged↗
PubMed2005

Rare case of carcinoid tumor arising within teratoma in kidney.

Not all enhancing lesions in the kidney are renal cell carcinoma. We report a rare case of a carcinoid tumor arising within a teratoma of the kidney in an asymptomatic female patient. Carcinoid tumors and teratomas involving the kidneys are rare. The two entities existing simultaneously in the same kidney are exceptionally unique. Still, the radiographic characteristics of these lesions have been previously described and should be familiar to practicing physicians.

Carcinoid Tumor↗
PubMed2005

Geometry and temperature distribution during radiofrequency tissue ablation: an experimental ex vivo model.

PURPOSE: To investigate the temperature distribution and geometry of lesions created by radiofrequency (RF) tissue ablation. MATERIALS AND METHODS: We developed an ex-vivo thermal model based on the ability of egg whites to coagulate at 62 degrees to 65 degrees C. This property allows us to observe and record the formation of "lesions" created by different commercially available RF generators and probes. RESULTS: The lesions created by the Radionics Cool-Tip RF system were mostly cylindrical or barrel-shaped, while RITA StarBurst XL and StarBurst XLi electrodes produced cone-like or mushroom-shaped lesions. The time required to achieve maximum lesion size was between 3 and 5 minutes in most trials. The formation of lesions stopped when thermodynamic equilibrium was achieved. CONCLUSIONS: The geometry of lesions does not correlate precisely with manufacturer reports, which describe spherical lesions for both RF systems. The 12-minute treatment cycle recommended by company's algorithm may not be necessary because lesion formation was completed and thermodynamic equilibrium was reached significantly earlier. We believe the results of our study may be useful in better understanding the RF ablation process, better planning, and improvement of clinical outcome.

Animals↗
PubMed2005

Computer-assisted laparoscopic pyeloplasty: University of Miami experience with the daVinci Surgical System.

PURPOSE: We report our experience with laparoscopic pyeloplasty using the daVinci surgical platform. PATIENTS AND METHODS: We routinely performed laparoscopic pyeloplasties prior to acquiring the daVinci system. We prospectively evaluated 26 computer-assisted laparoscopic pyeloplasties (CLP) performed since acquiring the device in March 2003. There were 15 male and 11 female patients with a mean age of 34.5 years, who underwent right-sided procedures in 11 cases and left-sided procedures in 15 cases. Four patients (15%) had secondary ureteropelvic junction obstruction. All procedures were performed through a transperitoneal approach over stents placed preoperatively. The operative time excluded the time needed for stent insertion. Radiographic objective success was defined as adequate cortical drainage (t (1/2) < or =15 minutes) and preserved or improved renal function on MAG-3 diuretic renography. RESULTS: A total of 23 dismembered pyeloplasties and 3 Y-V plasties were performed. In five patients, nephroscopy was performed for stone removal. The mean operative time and blood loss were 245 minutes and 69 mL, respectively. There were no intraoperative complications or open conversions. Three minor postoperative complications were noted. The mean length of hospital stay was 2 days (range 1-5 days). In 19 evaluable patients, at a median follow-up of 6 months (range 2-10 days), 15 (79%) had complete symptom resolution, while 3 (16%) had marked symptom improvement. The overall subjective improvement rate thus was 95%. The objective success rate based on our strict diuretic renography criteria was 100%. The overall clinical success rate was 95% (18/19). CONCLUSIONS: Robot-assisted laparoscopic pyeloplasty is a feasible alternative to laparoscopic or open pyeloplasty with excellent short-term subjective and objective success rates.

Adolescent↗
PubMed2004

Trocar arrangement for HALS.

The appropriate position of the hand-access device and trocars for hand-assisted laparoscopic surgery depends on several factors, including the surgeon's preference, physical stature, and handedness; the patient's anatomy; and the type of procedure being performed. This article reviews the options, including measures for special circumstances such as patient obesity.

Equipment Design↗
PubMed2004

Application of strict radiologic criteria to define success in laparoscopic pyeloplasty.

PURPOSE: To review our experience and utilize rigorous radiologic criteria to establish success in laparoscopic pyeloplasty. PATIENTS AND METHODS: The hospital records of consecutive adult patients who underwent laparoscopic pyeloplasty for ureteropelvic junction (UPJ) obstruction during a 5-year period at our institution were reviewed. We identified 47 candidates for study inclusion. With one open conversion secondary to excessive fibrosis and one patient requiring repeat laparoscopic pyeloplasty for recurrence, 46 patients with 47 renal units were included for analysis. Thirteen renal units had prior surgery for UPJ obstruction. Preoperative and postoperative symptomatology were compared to determine subjective outcome. Mercaptoacetyltriglycine (MAG3) nuclear renography was performed preoperatively and postoperatively to assess differential renal function (DRF) and obstruction, defined as a T1/2 -20 minutes, and evaluate objective success. There were 34 dismembered and 13 Y-V pyeloplasties. RESULTS: The mean operative time was 341.6 minutes (range 200-717 minutes). The mean preoperative T1/2 was 48.4 minutes (range 14 minutes-xc), with a mean DRF of 39.8% (range 22%-60%). The mean postoperative T1/2 was 9.32 minutes (range 2-27 minutes), and the mean DRF was 39.5% (range 7%-57%). The average length of hospital stay was 2.25 days (range 1-3 days). At a mean follow-up of 19.93 months (range 2-55 months), the subjective success rate was 95.7%, and the objective success rate was 93.6%. CONCLUSION: Even when using strict radiologic criteria to define success, laparoscopic pyeloplasty is found to be similar to open surgery in its efficacy for the correction of adult UPJ obstruction.

Adolescent↗
PubMed2004

Internet based multi-institutional clinical research: a convenient and secure option.

PURPOSE: As randomized, prospective trials have become an integral part of clinical research, multi-institutional, collaborative research has become a necessity. However, it may be cumbersome for participants at remote facilities to participate because the submission and compilation of data and results are at times lengthy processes. Internet based clinical studies have been found to be a rapid, easily accessible, safe and secure method of performing multi-institutional trials. MATERIALS AND METHODS: The Internet was used at geographically distant medical centers to enroll patients into a multi-institutional, prospective, randomized trial for the management of lower pole renal calculi. The Clinical Research Web-based Information Center secure computer web based program (Simplified Clinical Data Systems, Amherst, New Hampshire) was established to input preliminary demographic and clinical data, randomize patients, and collect treatment and followup information without paper chart documentation. The primary investigators in the study were sent a questionnaire to determine the ease of use of this Internet based program. The results were tabulated. RESULTS: A total of 112 patients from 21 participating institutions were randomized into the secure web site for inclusion into a lower pole renal stone clinical trial. Of the investigators 64% responded to the questionnaire. The majority of those having enrolled patients into the study reported no difficulties or only minimal difficulties in navigating the web site. Moreover, investigators from remote locations throughout North America described the improved convenience, rapid transmission of information, and ability to review and update patient data as benefits of enrolling patients using the Internet. The Internet based system also permits the prompt compilation of data at the host research site for performing interim data assessments and eventually the final analysis. CONCLUSIONS: A web based data collection center allows for large, multi-institutional trials to be done with unprecedented accuracy and efficiency. Through centralization of data capture, and real-time study monitoring and data analysis the system removes these responsibilities from those at individual test sites, permitting investigators to concentrate instead on other aspects of the study and its progress. State-of-the-art security protects all information to ensure confidentiality. The Internet may prove to be an invaluable tool in the future of clinical research.

Biomedical Research↗
PubMed2003

Radiofrequency interstitial tissue ablation: wet electrode.

Minimally invasive methods for destroying tissue have been investigated for more than a decade, and growing interest has emerged in small probe or needle ablative techniques. Many energy sources that freeze or heat tissue have been studied. This paper discusses radiofrequency (RF) thermal therapy as delivered by the saline-augmented ("wet" or virtual) electrode. The technique modifies the electric field distribution and the resultant heat deposition within tissues by interstitially infusing a highly conductive electrolyte solution during the application of RF energy. We consider the mechanism of action of the saline-augmented probe, with emphasis on tissue electrical impedance, temperature distributions, and how the fluid circumvents the limitations of standard "dry" probes. If optimized for the particular application, the wet electrode can produce small to large ablation volumes quickly and controllably with a single needle stick. Because there is no desiccation or extremely high temperature, the tissue is not subjected to a phase shift of carbonization, which may reduce post-treatment inflammation and improve healing. The liquid RF electrode will find applications in the interstitial treatment of various tissues, including tumors.

Animals↗
PubMed2003

Hand-assisted laparoscopic nephrectomy for stage T1 and large stage T2 renal tumors.

BACKGROUND AND PURPOSE: Standard laparoscopic nephrectomy (LN) has been shown to be as effective oncologically as open surgery for both stage T1 and stage T2 renal tumors. While much has been published regarding the increasing indications for laparoscopic nephrectomy, there is little in the literature regarding the advantages of hand-assisted laparoscopy (HAL) for the treatment of large (>7-cm) stage T2 renal tumors. To our knowledge, this study is the first to directly compare the results in pathologic stage T1 and stage T2 tumors. Our aim was to assess whether HAL nephrectomy for these larger tumors maintains the same advantages enjoyed by HAL for the smaller ones (<7 cm). PATIENTS AND METHODS: One hundred HAL renal extirpative procedures were performed over a 3-year period. Of these, 60 were radical nephrectomies for malignant disease, of which 50 tumors were stage T1 and 10 stage T2. Standard HAL nephrectomy was performed through a vertical midline or paramedian incision, and the specimen was sent for histologic examination and tumor staging. We retrospectively analyzed our charts to determine if HAL nephrectomy for T2 tumors was as advantageous as for T1 tumors. We collected data on patient age, ASA score, average tumor size, estimated blood loss, operative time, conversion rate, rate of complications, and length of hospital stay. Follow-up ranged from 4 to 26 months with a mean of 11 months. RESULTS: The mean size was 4.68 and 9.22 cm for stage T1 and T2 tumors, respectively. Intraoperatively, stage T2 tumors were associated with less blood loss than were T1 tumors (105 mL v 190 mL). Operative times were equivalent, at 190 and 185 minutes for stage T1 and T2, respectively. No open conversions were required in the T2 group v four (8.7%) in the T1 group. Three of these open conversions were seen in the first 25 HAL cases. No complications or conversions were seen in the stage T2 patients. Of note, the majority of the operations for stage T2 disease were performed after the learning curve had been surpassed. CONCLUSION: The HAL nephrectomy maintains the benefits associated with standard LN. Stage T1 and T2 tumors are equally amenable to HAL nephrectomy, enjoying the same perioperative advantages. The larger size of the higher-stage tumors does not appear to hinder intact organ removal via a 7-cm hand incision. For the novice laparoscopist, we recommend approaching smaller tumors first with HAL nephrectomy, as there is a learning curve. As surgical expertise with HAL nephrectomy increases, larger tumors (stage T2) can be removed safely and expeditiously with little blood loss and a low complication rate. In the short term, patients with stage T2 cancers appear to enjoy the same disease-free survival rate as those with tumors of lower stage. Longer-term follow-up is clearly needed; however, we anticipate the same excellent results as have been demonstrated by others performing conventional radical LN.

Blood Loss, Surgical↗
PubMed2003

Variables affecting deflection of a new third-generation flexible ureteropyeloscope (DUR-8 elite).

BACKGROUND AND PURPOSE: We performed an ex vivo study to measure the effects of various factors on the deflection angles of a new flexible ureteroscope with active primary and secondary deflections. MATERIALS AND METHODS: Active primary and secondary deflections in different sequences were measured initially without working devices (baseline measures). Nine different working instruments were then placed in the working channel, and alterations in ureteroscope deflectability were measured. RESULTS: Baseline measures showed excellent angles of deflections, consistent with the manufacturer's reporting. Among the wires tested, only the stiff wire had a negative (minor) impact on deflectability. There were similar minimal decreases of deflection with baskets. The 1.6F electrohydraulic lithotripsy (EHL) probe had minimal influence on deflectability compared with the 3.0F EHL probe. The 200-microm and 365-microm laser fibers significantly (>20 degrees ) decreased the angles of deflection. CONCLUSIONS: In spite of the changes in deflectability with almost all working instruments, there were no significant decreases in the angles with most of them. The sequence is important in obtaining optimal deflection.

Equipment Design↗
PubMed2003

Limitations of noncontrast CT for measuring ureteral stones.

BACKGROUND AND PURPOSE: Patients with renal colic are frequently evaluated in the emergency room with a helical noncontrast CT scan (NCCT) as the primary imaging modality. Treatment decisions are often based on the size of the ureteral stone(s). We wished to assess the accuracy of NCCT in estimating ureteral stone size compared with plain abdominal (KUB) films. PATIENTS AND METHODS: Forty-eight patients were identified who had ureteral stones seen on NCCT and KUB films performed on the same day. The number of consecutive images on which a ureteral stone was visible on NCCT was multiplied by the reconstruction interval of 5 mm to create a size estimate, which was compared with the measurements of the same stone seen on the KUB film. RESULTS: The NCCT overestimated stone size by approximately 30% to 50% compared with KUB. CONCLUSION: Counting the number of consecutive NCCT images depicting a ureteral stone is not an accurate method of stone measurement when a reconstruction interval of 5 mm is used. Urologists should consider stone measurement techniques carefully and understand the limitations of imaging studies when evaluating patients with symptomatic ureteral stones.

Analysis of Variance↗
PubMed2003

Intracorporeal lithotripsy: which modality is best?

PURPOSE OF REVIEW: A large number of related articles published within the last year were reviewed. Different types of intracorporeal lithotripter devices were compared according to their advantages, disadvantages, efficacy, safety and clinical applications. General directions of future developments are discussed. RECENT FINDINGS: Ultrasound lithotripters employed through rigid endoscopes provide high fragmentation rates (97-100%) and stone free rate (94%). Clinical evaluation of a new combination ultrasound and pneumatic lithotripter reported an overall stone free rate of 80-89.7%. No major complications were observed. The holmium:YAG (Yttrium-Aluminum-Garnet) laser lithotripter is able to destroy all compositions of stone. The stone free rate for ureteral stones is close to 100%. Complications are rare and minimal. Newer wavelengths such as erbium:YAG are currently impractical. There are limited clinical data regarding frequency-doubled double-pulse neodymium:YAG laser lithotripsy. SUMMARY: Ultrasound lithotripsy is still the preferable modality applied through rigid endoscopes. A new combination of ultrasound and pneumatic impactor includes the advantages of each mode. The holmium:YAG laser lithotripter is the method of choice for flexible endoscopic procedures. Further development of new lithotripters with different energy sources and their combination is necessary.

Humans↗
PubMed2003

Estimation of acute blood loss in the anticoagulated rabbit model using 3 modalities of radio frequency energy ablation.

PURPOSE: An anticoagulated animal model was tested to evaluate estimated acute blood loss (EABL) following tissue ablation with 3 modalities of radio frequency (RF) thermal energy. MATERIALS AND METHODS: Four groups of randomly divided rabbits were established. Group 1 (3 control and 3 anticoagulated rabbits) underwent sham treatment (noRF), group 2 (2 control and 7 anticoagulated) received single probe dry RF (dRF) (475 KHz and 5 W for 2 minutes), group 3 (2 control and 7 anticoagulated) received single probe wet RF (wRF) (475 KHz with 14.6% hypertonic saline at 50 W for 40 seconds) and group 4 (3 control and 7 anticoagulated) was treated with vapor RF (vRF) (0.9% normal saline for 10 seconds). Oral warfarin sodium was the anticoagulant. Following a midline incision ablation was performed on the left kidney and liver. Pre-weighed gauze pads were used to collect EABL for a 5-minute observation period after needle probe removal. Temperature data were recorded from the right kidney using fiberoptic thermocouples. Lesions were grossly inspected and measured. RESULTS: Anticoagulation resulted in super anticoagulated animals with an average prothrombin time of almost 140 seconds. EABL was the least from the ablated left kidney for vRF (50 mg), followed by wRF (260 mg), dRF (390 mg) and noRF (1,800 mg). EABL was the least from the liver for vRF (10 mg), followed by wRF (470 mg), dRF (1,260 mg) and noRF (2,680 mg). A greater percent of total ablative time at 10 mm was spent at greater than 50C during wRF and vRF. Measured ablative lesions size was largest following vRF ablation. CONCLUSIONS: The thermal coagulative effects of RF ablation resulted in less bleeding compared with controls in this orally anticoagulated animal model. The novel RF modality vRF is introduced.

Animals↗