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Biomedical subjects

D H Bagley

Publications and source records attributed to D H Bagley.

At least 37 records · Page 2Linked to original sources

Three-dimensional endoluminal ultrasonography of the ureter.

Endoluminal ultrasonography has been useful in demonstrating the ureteral and periureteral anatomy. Devices now available give cross-sectional images. A computer program is available to reconstruct these images into three-dimensional (3D) representations. Endoureteral sonography was performed using 6.2F endoluminal ultrasound catheters connected to a dedicated ultrasound unit giving cross-sectional images. The images along the segment in the study were collected by advancing the catheter to the most proximal portion and pulling it in antegrade fashion through the segment with a step-pulling device. The images were collected on videotape and reconstructed into 3D representations using a dedicated 3D computer system (Lis 6000-A). Anatomic features studied included ureteral strictures, obstructed ureteropelvic junction, ureteral neoplasms, and the ureterovesical junction. In each case, additional information and appreciation of the structure could be obtained with the 3D reconstruction. Endoluminal ultrasonography has provided an additional dimension to imaging of the ureter. Three-dimensional reconstruction of these images can give additional information regarding the longitudinal appearance of ureteral segments without the need for development of new ultrasound transducers. It can offer appreciation of anatomic features not evident with two-dimensional imaging alone.

Adult↗

Ureteroscopic endopyelotomy at a single setting.

PURPOSE: Endopyelotomy has become the initial treatment of choice for ureteropelvic junction obstruction. Debate persists regarding the preferred approach (percutaneous or ureteroscopic) and the need for preoperative stenting. We review our experience with ureteroscopic endopyelotomy without preoperative stenting. MATERIALS AND METHODS: We treated 21 patients a mean of 37 years old who had ureteropelvic junction obstruction with ureteroscopy and without preoperative stenting. Endoluminal ultrasound was performed in all cases for imaging the periureteral anatomy. A minimum of 1 year of followup is available in all cases. Success was defined as pain-free status with resolution of obstruction on diuretic renal scintigraphy. RESULTS: Success was achieved in 17 of 21 patients (81%). Complications included stent irritation, postoperative urinary tract infection and stent displacement requiring repositioning in 1 case each. Crossing vessels in 57% of the patients affected success (67 versus 100% in those with and without crossing vessels, respectively). No patient had significant hemorrhage. CONCLUSIONS: Ureteroscopic endopyelotomy without preoperative stenting is effective and safe for ureteropelvic junction obstruction.

Adolescent↗

Ureteroscopic management of intrarenal calculi.

PURPOSE: To determine its potential role in stone therapy, we evaluated our experience with the ureteroscopic removal of intrarenal calculi in 100 patients. We review the indications, techniques, stone-free and overall success rates, and complications. MATERIALS AND METHODS: From July 1994 to December 1996 ureteroscopic stone removal was attempted in 100 patients a mean of 52 years old who had renal calculi. Indications for treatment included concurrent ureteral stones in 56 cases, and failed extracorporeal shock wave lithotripsy, medical or percutaneous management as well as obesity and anatomical anomalies. There were 2 or more calculi in the affected kidney in 68 patients and stones greater than 6 mm. in 67. Treatment of intrarenal calculi was performed with flexible ureteroscopes, a laser or electrohydraulic lithotriptor and endoscopic graspers. The number and size of calculi were noted in each patient. Stone-free and overall success rates defined as 1 residual fragment less than 3 mm. were noted at 1 and 3-month followup visits. RESULTS: The overall success rate was 89%. Ureteroscopic treatment of intrarenal calculi resulted in a 77% stone-free rate. Of the 23 patients with residual calculi 12 (52%) had a single residual fragment less than 3 mm. The targeted stone was removed or fragmented in 98 patients (98%) and no ureteral calculi remained postoperatively. As expected, the number and size of the original stones inversely correlated with the success rate. There were no intraoperative complications, and only 3 urinary tract infections and 3 fevers were noted postoperatively. CONCLUSIONS: The use of smaller diameter ureteroscopes, better working instruments and more effective lithotriptors allow calculi in all parts of the collecting system to be engaged and treated. Success rates throughout the whole collecting system are comparable to if not better than those of extracorporeal shock wave lithotripsy and percutaneous approaches.

Adolescent↗

Ureteroscopic retrograde endopyelotomy.

With improvements in technology, we continue to seek new surgical techniques to approach old surgical issues. Antegrade percutaneous endopyelotomy has become the most common first-line approach to treatment of ureteropelvic junction obstruction, however, it is now possible to treat this condition successfully through a retrograde ureteroscopic approach. By combining the latest small ureteroscopes with the technology of endoluminal ultrasound, it is possible to treat this disease in a single setting without the complications of ureteral strictures or significant postoperative hemorrhage, thereby eliminating the need for a nephrostomy tube and dramatically reducing the morbidity of the procedure.

Catheterization↗

Intrarenal use of the holmium laser.

BACKGROUND AND OBJECTIVE: We investigated the safety, effectiveness, and techniques of the holmium (Ho:YAG) laser intrarenally. Data are presented on 52 patients who were treated with the Ho:YAG laser intrarenally for urinary calculi or neoplasms. STUDY DESIGN/MATERIALS AND METHODS: The Ho:YAG laser has a wavelength of 2,100 nm, which is delivered in pulsed fashion via a small flexible quartz fiber (365 microns), which is placed through a working channel (> 2.2 Fr) of a small diameter endoscope. RESULTS: Sixty-three intrarenal procedures were performed with the Ho:YAG laser for calculi and neoplasms. Twenty-four procedures were performed for intrarenal neoplasms. Average total energy used in these patients was 2.61 kilojoules (kJ) with a maximum of 15.28 kJ. Thirty-nine procedures were performed for intrarenal calculi; 7/39 procedures were approached percutaneously. Average total energy in stone patients was 5.41 kJ with a maximum of 37.77 kJ. CONCLUSION: The Ho:YAG laser can be used safely and effectively to treat intrarenal calculi or neoplasms. All types of calculi were fragmented and all patients with intrarenal tumor were treated successfully. There were no vascular or renal injuries and there was no evidence of renal loss. No intrarenal strictures were seen on follow-up. The Ho:YAG laser energy can be delivered through a small flexible quartz fiber passed through a small diameter endoscope. The techniques and applications of the Ho:YAG laser make it well suited for urologic application.

Adult↗

Adjuvant mitomycin C following endoscopic treatment of upper tract transitional cell carcinoma.

PURPOSE: A variety of topical agents have been used for transitional cell carcinoma of the upper tract. Mitomycin C has limited systemic absorption when given intravesically because of its high molecular weight. We reviewed our experience with mitomycin C following endoscopic treatment of upper tract transitional cell carcinoma. MATERIALS AND METHODS: Since 1991, 19 patients (21 renal units) have undergone a total of 28 treatments with mitomycin C for high volume, recurrent or multifocal transitional cell carcinoma. Of the 19 patients 12 had an absolute indication for nephron sparing treatment. Following ureteroscopic biopsy and treatment of upper tract transitional cell carcinoma, 40 mg. mitomycin C in 3 divided doses was instilled via a ureteral catheter, which was clamped between doses to give an exposure time of 30 minutes. Eighteen patients have undergone ureteroscopic surveillance following a total of 26 treatments. RESULTS: No systemic side effects occurred during or after treatment with mitomycin C. One patient had a prominent local inflammatory reaction following neodymium:YAG ablation and mitomycin C treatment of a renal pelvic tumor. The average size of the treated tumors was 17 mm. (range 5 to 30). The grade of the tumors (when known) was 1 in 5 patients, 1 to 2 in 2, 2 in 8 and 3 in 4. Most tumors were treated with either neodymium:YAG (6 cases) or holmium:YAG laser (8) or a combination of both (8). Following 1 to 4 treatments with mitomycin C 11 of 19 evaluable renal units (58%) were rendered free of disease. Six of those 11 renal units (54%) had an ipsilateral recurrence after a mean of 30 months of followup, 4 of which were treated endoscopically, and 7 (64%) are now disease-free without extirpative surgery. Four patients have undergone nephroureterectomy for persistent or recurrent disease. No patient has suffered local or distant progression of disease. CONCLUSIONS: Instillation of mitomycin C for upper tract transitional cell carcinoma appears to be safe and can be considered for adjuvant treatment in select cases. More data are necessary to determine its efficacy.

Aged↗

Use of p53 in the diagnosis of upper-tract transitional cell carcinoma.

OBJECTIVES: To assess the usefulness of p53 staining of cytology specimens obtained ureteroscopically in the diagnosis of upper-tract transitional cell carcinoma (TCC). METHODS: We collected specimens from 43 patients undergoing a total of 50 ureteroscopic procedures for a variety of indications, including the diagnosis of TCC. Specimens were obtained by direct biopsy with forceps or basket whenever possible. We examined specimens for evidence of TCC by cytospin as well as cell block for any visible fragments. Each specimen was then stained for overexpression of p53 by immunohistochemical staining, and the degree of staining was graded. Eight patients subsequently underwent nephroureterectomy; the pathologic specimens were stained for p53 and compared with the cytology results. RESULTS: Staining for p53 was positive in specimens from 36 of 50 procedures, including all 28 with ureteroscopic or cytologic evidence of TCC (P < 0.0001). By contrast, cytology accurately diagnosed only 23 of the 28. Specimens from all 14 procedures that were negative also stained negative for p53. Specimens from all 8 procedures with no tumor seen and atypical cytology stained positive for p53; 4 of 5 patients with adequate follow-up have had a tissue diagnosis of TCC at that site. Overall, 35 of the 36 specimens that stained positive for p53 were obtained from patients with some history of TCC (P < 0.0001). No significant association could be found between degree of staining and grade (P = 0.3034). The degree of staining of ureteroscopic biopsy specimens was identical to that of the nephroureterectomy specimen in 6 of 8 cases. CONCLUSIONS: p53 nuclear protein staining of cytology specimens obtained ureteroscopically appears to correlate well with the presence of upper-tract urinary TCC. Further study is needed to determine if it can provide a definitive diagnosis in cases with indeterminate cytologic findings.

Carcinoma, Transitional Cell↗

Ureteroscopic biopsy: technique and specimen preparation.

Because tissue samples obtained ureteroscopically are small, the techniques for biopsy and for handling and processing the samples are crucial. Our aim is to describe the biopsy technique in great detail so other centers can reproduce it. Patients were evaluated by retrograde ureteropyelography and ureteroscopy for diagnosis. The entire collecting system was examined using a combination of small-diameter rigid and flexible ureteroscopes. Samples were retrieved by aspiration, saline lavage, or, when possible, biopsy of visible tumor by a basket or cup forceps. Multiple samples were obtained from all patients. Fresh specimens were hand delivered to the cytopathology laboratory, where they were evaluated with the cytospin technique. A cell block was prepared whenever there was any visible tissue in the sample. Since we have practiced this technique of handling specimens, our ability to diagnose and grade upper tract neoplasms ureteroscopically has improved markedly. Use of this technique can improve the diagnostic accuracy of ureteroscopic biopsy.

Biopsy, Needle↗

Upper-tract transitional cell carcinoma.

Advances in ureteroscopic techniques have made it possible to treat many upper-tract tumors conservatively. Such treatment has demonstrated acceptable survival and renal preservation in high-risk patients, particularly those with a solitary kidney, bilateral tumors, poor renal function, or prohibitive operative risk. It is also preferred in patients with grade I TCC, particularly when located in the distal ureter. For patients with regionally extensive upper-tract urothelial neoplasms, use of endourologic techniques should be considered to control hemorrhage, relieve obstruction, and preserve as much functioning renal tissue as possible. Success with small, solitary, low-grade tumors allows the application of this technique to patients with a normal contralateral kidney on an elective basis. Adjuvant BCG or mitomycin C therapy appears to be safe, but confirmation of any benefits awaits the results of larger trials. Benign neoplasms can occur in the upper urinary tract and should be distinguished from TCC, thus avoiding more radical treatment for a benign lesion. Endoscopic surveillance should be maintained because recurrences can develop without radiographic evidence.

Carcinoma, Transitional Cell↗

Spiral computed tomography for staghorn calculi.

OBJECTIVES: To assess the utility of spiral computed tomography (CT) with three-dimensional reconstruction for preoperative planning of percutaneous nephrostolithotomy in patients with complex branched calculi (full staghorns). METHODS: Patients with complex branched stones were imaged with spiral CT with three-dimensional reconstruction. These images were compared with standard imaging modalities, including excretory urography and plain radiographs, for planning percutaneous access for nephrostolithotomy. The utility of the scan was evaluated. RESULTS: Ten patients with branched calculi were studied. Anatomic abnormalities were present in 5 patients. Excellent three-dimensional images were obtained in all patients without any complications related to the study. In 1 patient with multiple calculi in a horseshoe kidney, the three-dimensional image indicated a branched stone. The spiral CT scan was not helpful in directing percutaneous access in any patient. In a single patient, residual fragments noted during nephrostolithotomy were located by reference to the spiral CT scan. CONCLUSIONS: Spiral CT scans with three-dimensional reconstruction provide three-dimensional imaging of branched renal calculi. This modality provides minimal additional information over that obtained from standard radiographic studies for guiding nephrostolithotomy and cannot be recommended as a routine preoperative study. It was helpful in 1 patient to locate a residual fragment.

Adult↗

Grading of upper urinary tract transitional cell carcinoma by computed DNA content and p53 expression.

OBJECTIVES: Transitional cell carcinomas of upper urinary tract (uttTCC) constitute 5% to 6% of all urothelial tumors. Ureteropyeloscopy has become the standard for clinical evaluation of uutTCC. Moreover, endoscopic treatments have been advocated as a conservative approach for low grade tumors or patients with intermediate grade tumors whose renal function is compromised. Therefore, grading has become the most predictive variable in defining therapeutic approach. In addition to morphologic evaluation, a series of biologic markers may be used to increase the accuracy of grading such as DNA analysis and p53 protein expression. In this study, we have evaluated these markers by means of cell image analysis with the SAMBA 400 system. METHODS: Thirteen cases of uttTCC were studied with cytologic smear, cell block, and histologic confirmation. DNA analysis was performed on cytologic smear. Immunostaining was performed on cell blocks. A grade was assigned on the basis of DNA evaluation and p53 expression quantitation. These grades were combined for each case and compared with the initial cytologic grading and the final histologic grading. RESULTS: Cytology alone diagnosed TCC in all but 1 case that was diagnosed atypical. Discrepancies were found in primary grading: cytologic grading concurred with histologic grading in 6 of the 13 cases. CONCLUSIONS: These results, although in a limited but selected number of cases, show the potential of computerized evaluation of biologic markers as parameters for a more objective grading of tumors.

Biomarkers, Tumor↗

Ureteroscopy. Development and instrumentation.

Advances in ureteroscope and working instrument designs now allow the treatment of a variety of upper urinary tract disorders in a minimally invasive fashion. This field has benefited from the close cooperation between endourologists, engineers, and manufactures. Continued cooperation should result in even further improvements in ureteroscopic instrumentation. This article also presents the development of flexible and rigid ureteroscopes and working instruments. Knowledge of these features can assist the urologist in choosing the most appropriate tool for different ureteroscopic tasks.

Equipment Design↗

Initial use of Browne Pneumatic Impactor.

To determine the safety and effectiveness of the Browne Pneumatic Impactor (BPI), a new pneumatic mechanical lithotripter, in fragmenting urinary calculi. Nine patients were treated between November 1995 and March 1996. The calculi were located in the bladder and urethra in one case, the bladder alone in one case, the distal ureter in six cases, and the proximal ureter in one case. The device was used through semirigid and actively deflectable, flexible fiberoptic endoscopes. All patients were treated on an outpatient basis. Fragmentation of the urinary calculi was successful in all patients when the stone could be reached endoscopically. The device worked irrespective of stone size or composition. There were no intraoperative or long-term complications directly related to the use of the device. All treated patients were stone free at 1-month follow-up, with no evidence of ureteral obstruction. The results of our initial study show that the BPI is a simple, safe, and reliable intracorporeal lithotripter, able to fragment the hardest urinary calculi through semirigid and actively deflectable, flexible fiberoptic endoscopes with no complications related to use of the device.

Adult↗

Endoluminal sonographic evaluation of ureteral and renal pelvic neoplasms.

The objective of this study was to demonstrate the feasibility of endoluminal ultrasonography as an adjunct to endoscopy for the evaluation of urothelial neoplasms. An endoluminal ultrasound system using a 12.5 or 20 MHz transducer housed in a 6.2 French catheter was used intraureterally in 38 patients being evaluated endoscopically for suspected tumors in the renal pelvis or ureter. The ultrasonographic, endoscopic, and pathologic findings were evaluated. The location, size, and sonographic characteristics of the tumors in the upper urinary tract were well demonstrated. The information obtained by this technique can be used to guide endoscopic biopsy and laser ablation of the tumor. Endoluminal ultrasonography also has proved helpful in defining the location of a tumor relative to an adjacent vessel and in identifying crossing vessels that cause extrinsic filling defects in the ureter. In a few pathologically correlated cases, endoluminal ultrasonography was accurate in assessing invasion. We have evaluated successfully a variety of non-neoplastic filling defects in relatively few cases. Determination of the eventual usefulness of this technique awaits greater clinical experience and large clinical trials.

Adolescent↗

Diagnostic accuracy of ureteroscopic biopsy in upper tract transitional cell carcinoma.

PURPOSE: Our aim was to determine the accuracy of ureteroscopic biopsies and cytological techniques compared to open surgical specimens of upper tract transitional cell carcinoma. MATERIALS AND METHODS: From 1985 to 1995, 51 cases of upper tract transitional cell carcinoma were diagnosed ureteroscopically and distal ureterectomy or nephroureterectomy was performed. Each patient underwent direct ureteroscopic inspection and biopsy. Fresh samples were delivered to the cytopathology laboratory, where they were examined using cytospin and smear. A cell block was prepared when visible tissue was present. Grades of ureteroscopic biopsies were compared to grades and stages of surgical specimens in 42 cases. RESULTS: Cytological evaluation was positive for malignancy in 48 of the 51 cases (94.1%). Grading of ureteroscopic specimens was possible in 42 cases (82.4%). Transitional cell carcinoma grade on ureteroscopy accurately predicted tumor grade and stage in the surgical specimens. Of 30 low or moderate grade ureteroscopic specimens 27 (90%) proved to be low or moderate grade transitional cell carcinoma in the surgical specimens, while 11 of the 12 high grade ureteroscopic specimens (91.6%) proved to be high grade transitional cell carcinoma (p < 0.0001). Of 30 low or moderate grade ureteroscopic specimens 26 (86.6%) had a low stage (Ta or T1) tumor. In contrast, 8 of 12 high grade ureteroscopic specimens (66.7%) had invasive tumor (stage T2 or T3) in the surgical specimen (p = 0.0006). CONCLUSIONS: Ureteroscopic inspection and biopsy combined with cytological techniques provide accurate information regarding grade and stage of upper tract transitional cell carcinoma.

Adult↗

Ureteroscopic treatment and surveillance of upper urinary tract transitional cell carcinoma.

PURPOSE: We determined the efficacy of ureteroscopic treatment of upper urinary tract transitional cell carcinoma. MATERIALS AND METHODS: Of 92 patients diagnosed with upper urinary tract transitional cell carcinoma at our institution from 1985 to 1995, 38 (41 kidneys) underwent ureteroscopic treatment and followup. Semirigid and flexible ureteroscopes were used to examine the collecting system. Tumors were biopsied, and treated with fulguration, the neodymium:YAG laser and/or the holmium:YAG laser. Patients were treated every 6 to 12 weeks until tumor-free and then followed on a strict endoscopic protocol. RESULTS: Mean and median followup was 35.1 and 26 months, respectively (range 3 to 116). Grading of ureteroscopic biopsies was possible in 40 of 41 cases. Initial grading of tumors was low (grade 1 or 1 to 2) in 21 kidneys, grade 2 in 14 and grade 3 in 5. Of 41 kidneys 28 (68%) were documented as tumor-free ureteroscopically at some time following treatment, including 8 (29%) with subsequent recurrences that were treated endoscopically and 24 (86%) with no evidence of disease at the most recent followup. No patient to date has had progression of disease during endoscopic followup. High tumor grade, size and multifocality were significantly associated with tumor persistence and recurrence. Location in the kidney versus ureter was not a significant prognostic factor. Of the recurrent tumors 75% were not identified radiographically but were only discovered endoscopically. Two of 8 kidneys removed after endoscopic treatment had no tumor stage (pT0). CONCLUSIONS: Endoscopic treatment of upper urinary tract transitional cell carcinoma is a reasonable method to treat carefully select patients based on strict indications. Complete endoscopic followup at regular intervals is essential to rule out recurrences.

Aged↗

Endoluminal sonographic imaging of the ureteropelvic junction.

Endoluminal ultrasound imaging of the ureter can demonstrate the periureteral anatomy. Ultrasound probes are available as catheters from 3.5F to 6.2F. The transducer is available as a 12.5 or 20 MHz design and gives a cross-sectional image with penetration of 1.5 to 2 cm. Endoureteral ultrasonography has demonstrated blood vessels associated with the obstructed ureteropelvic junction (UPJ) in more than 50% of patients. These vessels have been located at all sites adjacent to the UPJ. The anteromedial location is the most common site. In comparison, only 8 significant crossing vessels were found in 44 patients with a normal UPJ. Inspection of the UPJ with a high insertion of the ureter demonstrates a characteristic sonographic image with a septum between the ureteral and renal pelvic lumen. Endoluminal ultrasonography of the obstructed UPJ can be used to guide the site of endopyelotomy to avoid damage to adjacent vessels. The presence of such vessels may also be related to the success of the procedure. An ultrasound-guided cutting device has been developed for preclinical studies.

Humans↗

Laparoscopic division of crossing vessels at the ureteropelvic junction.

Endopyelotomy has become an accepted mode of treatment for primary and secondary ureteropelvic junction (UPJ) obstruction, but a 15% to 30% failure rate persists. The presence of crossing vessels at the UPJ has been implicated as a common cause of complications, failures, and recurrences. In the past, renal angiography was necessary to identify crossing vessels. We have utilized endoluminal ultrasonography to identify crossing vessels at the UPJ and to guide endoscopic incisional techniques. Previously, whenever crossing vessels were identified that could not be safely avoided during endopyelotomy, we had recommended dismembered pyeloplasty, an open surgical procedure with a long recovery time. We report our experience with laparoscopic division of crossing vessels in two patients, one with a symptomatic horseshoe kidney. Each patient had a large crossing vessel identified by endoluminal ultrasonography; consequently, endopyelotomy was abandoned. The location and distribution of the vessels were then delineated by angiography. The aberrant vessels were dissected free and divided laparoscopically. The patients returned to work within 1 week. Follow-up diuretic renal scans showed complete resolution of obstruction (T1/2 < 10 minutes) in one patient; no change was noted in the patient with a horseshoe kidney. Both patients have remained free of symptoms and normotensive for more than 12 months. Laparoscopic division of crossing vessels may play a role in the treatment of patients with extrinsic ureteral obstruction from aberrant vessels.

Adult↗