Lower Ureter Research Articles

The Effect of Extracorporeal Electromagnetic Shock Waves on the Morphology and Contractility of Rabbit Ureter

Purpose Although extracorporeal shock wave lithotripsy (ESWL) is known to cause pathologic changes in various organs, little is known about its effects on the ureter, the target organ in ESWL of ureteral stones in situ. In this study, we sought to determine the short-term effects of ESWL on the ureter. Materials and Methods Left lower ureteral segments of 21 rabbits were removed to serve as the control group and 2000 shocks were applied to the right lower ureters. Groups of 7 rabbits were sacrificed 1, 3 and 5 days after shock wave exposure. While histomorphological alterations were examined under light and transmission electron microscopy, contractility of all ureters was determined in organ baths. Results The epithelial cells disclosed no change after shock wave application. Histologically the muscular layer was the most affected part of the ureter. There was interstitial and intracellular edema on light microscopy and marked chromatin and mitochondrial changes at the subcellular level. The adventitial layer was also edematous. These changes were prominent on days 1 and 3 and returned to normal on day 5. The contractility of the ureters on day 1 was significantly reduced (p less than 0.05). However, the contractility of the samples on days 3 and 5 were not significantly different from controls. Conclusion Our findings demonstrate that electromagnetic shock waves produce reversible morphological and functional changes in rabbit ureteric muscle.

Use of semirigid ureteroscopes for treatment of ureteral calculi

The objective of this study is to evaluate the efficacy of ureteroscopic lithotripsy as the treatment of ureteral stones in the recent era by comparing the result using a semirigid ureteroscope with the result using a conventional ureteroscope. Between 1991 and 1994, 136 patients with ureteral calculi underwent transurethral ureteroscopic lithotripsy in our hospital. From July 1991 to March 1993, 14F rigid ureteroscope with the rod lens system was used for 82 patients (group 1), whereas from April 1993 to July 1994 either a 9.5F or 7F semirigid fiberoptic ureteroscope was used for 54 patients (group 2). Insertion of ureteroscopes was performed under continuous irrigation of saline without mechanical dilation of the ureteral orifice in both groups. The rates of complete removal of stone at the first trial were 56.1% in group 1 and 72.2% in group 2 with the overall complete removal rate of 62.5%. The complete removal rates of stones in the upper, middle and lower ureters were 18.2%, 54.8% and 72.4% in group 1 and 14.3%, 72.7% and 88.0% in group 2, respectively. The major reasons for unsuccessful treatments was upward migration of stones during the procedure. As intraoperative complications, ureteral disruption occurred in 1 case in group 1, and ureteral perforation in 5 patients in group 1 (6.1%) and 2 in group 2 (3.8%). Acute bacterial infection with prolonged fever was observed in 3 patients in group 1 and in none in group 2. From these results, the new semirigid ureteroscope with fiberoptic imaging bundles made the transurethral lithotripsy a safer and more efficient procedure for the treatment of ureteral calculi especially those in the lower ureters.

A study of tumor location and prognosis in renal pelvic and ureteral cancer

A total of 245 patients with renal pelvic and ureteral cancer (transitional cell carcinoma) were retrospectively analysed for tumor location and prognosis. In 133 renal pelvic cancer patients, 34 patients (25.6%) had tumor in lower calyx, 33 patients (24.8%) in renal pelvis, 31 patient (23.3%) in upper calyx, 21 patients (15.8%) in whole renal pelvis and 7 patients (5.2%) in middle calyx, respectively. In 128 ureteral cancer patients, 60 patients (46.9%) had tumor in lower ureter, 27 patients (21.1%) in distal end of ureter, 26 patients (20.3%) in middle ureter, 12 patients (9.4%) in upper ureter and 3 patients (2.3%) in whole ureter. In combination of tumor location, 101 patients (41.2%) had tumor in only renal pelvis, 94 patients (38.4%) had in only ureter, 14 patients (5.7%) had in renal pelvis and ureter, 19 patients (7.8%) had in renal pelvis and bladder, 12 patients (4.9%) had in ureter and bladder, and 5 patients (2%) had in renal pelvis, ureter and bladder. Five year survival rate of renal pelvic cancer according to tumor location were 55.9% in upper calyx tumor, 60.8% in middle calyx tumor, 63.8% in lower calyx tumor, 60.2% in renal pelvic tumor and 63.8% in PUJ tumor, respectively. There were no significant difference between those 5 groups. Five years survival rate of ureteral cancer according to tumor location, 90% in upper ureteral tumor, 60.8% in middle ureteral tumor, 66.5% in lower ureteral tumor and 52.6% in tumor of distal end of ureter, respectively. Also in those 4 groups, there were no significant difference.(ABSTRACT TRUNCATED AT 250 WORDS)

Outpatient fragmentation of ureteral calculi with mini-ureteroscopes and laser lithotripsy.

Laser lithotripsy with mini-ureteroscopes is a minimally invasive method to fragment ureteral calculi. This study reviewed the efficacy and morbidity of outpatient laser lithotripsy for the treatment of ureteral calculi. The 248 patients were initially treated by outpatient ureteroscopy and laser lithotripsy with the Candela pulsed-dye laser over a period of 3 1/2 years. Thirty-six patients had prior unsuccessful fragmentation of ureteral calculi by SWL. Twenty-eight patients had undergone unsuccessful ureteroscopy with attempted basket extraction or attempted fragmentation with methods other than laser. Calculi were located in the upper ureter in 31% and in lower ureter in 69% of these patients. The 1-month stone-free rate was 92% for upper ureteral calculi and 96% for lower ureteral calculi, with an overall success rate of 94.7%. Ninety per cent of the patients were discharged the same day and 96% within 23 hours. Hospital admission was needed in only 4% of patients. Parenteral analgesia was required in 18% of patients, and major complications occurred in 0.8%. The combination of mini-ureteroscopes and laser lithotripsy is an effective method for fragmentation of ureteral calculi in outpatients with low morbidity and few complications.

In situ extracorporeal shock wave lithotripsy (ESWL) for the management of primary ureteric calculi in children

Lithotripsy was used to treat 19 children (3 to 16 years of age) with primary ureteric calculi. No attempts were made to mobillize the stones to the kidney. Stones were located in the upper ureter in seven patients, middle ureter in three, and lower ureter in nine. Stone size ranged from 5 to 25 mm (average, 10.4 mm). All treatments were performed in the outpatient unit. Two children required general anesthesia, and 17 received intravenous sedation. The mean amount of energy used was 17.8 kV, and the average number of shock waves was 5,489. Before commencement of lithotripsy, two patients needed ureteric catheterization, and two had placement of double pigtail catheters. Of the 18 children who had adequate follow-up, 17 (94.4%) were completely stone-free, without any complication. The authors conclude that in situ extracorporeal shock wave lithotripsy is a safe and effective method for the treatment of primary ureteric calculi in children.

Urinary Undiversion in Adults with Myelodysplasia: Long-Term Followup

A total of 14 women and 6 men 19 to 39 years old (mean age 27 years) with myelodysplasia underwent undiversion 8 to 29 years (mean 16) after ileal conduit diversion. The main reasons for diversion were incontinence in 17 patients and failed ureteral reimplants in 3, and those for undiversion were a desire for an improved quality of life in 16, increasing hydronephrosis in 4 and stomal problems in 3. Preoperative assessment included upper and lower tract imaging, and video urodynamics. Operations on the ureters included reimplantation into an intussuscepted nipple valve in 8 patients, tunneled reimplants into a sigmoid augmentation in 3 and the ureters joined to either the bladder or lower ureter without interposing bowel in 9. All reimplantations were done with nonrefluxing techniques. A total of 18 patients underwent bladder augmentation and 2 women in whom cystectomy was performed for pyocystis underwent substitutions. Simultaneous continence procedures in 18 patients included trigonal tubularization in 2, artificial sphincter implantation in 2, a bladder neck sling in 5 or bladder neck tapering and a sling in 9. The patients were followed for a mean of 69 months (range 21 to 133). Eight patients required reintervention within 1 year for problems, such as anastomotic leak in 1, bladder neck obstruction in 1, incontinence in 1, artificial urinary sphincter revisions in 1 and bladder stones in 1. One patient had a recurrent renal calculus 10 years after undiversion. All patients experienced either persistence of normal upper tract appearance or improvement and/or stabilization of hydronephrosis. Mean bladder capacity was 77cc preoperatively and 480cc postoperatively, while mean pressure at capacity decreased from 50 to 14cm. water with detubularized augmentation. Of the patients 17 are completely dry, 2 wear 1 pad per day and 1 has enuresis. All but 1 patient who voids with straining are on intermittent self-catheterization. All patients, on followup interviews, reported an improved quality of life without a stoma. We conclude that undiversion provides an improved quality of life and an acceptable morbidity rate. The choice of operation depends on the anatomy of the patient. We prefer a nonprosthetic type of incontinence procedure when intermittent self-catheterization is to be done. No long-term morbidity has yet been noted.

Ureteral extracorporeal shock wave lithotripsy utilizing Dornier MFL 5000.

Early reports indicated that stones in the upper ureter that have been manipulated back into the kidney have a higher success rate with SWL than those treated in situ. Difficulties in detecting stones in the mid and lower ureter with lithotripters using ultrasonographic localization also limit in situ SWL of ureteral calculi. We treated 254 patients with ureteral calculi (85 upper, 72 mid, and 97 lower) using in situ SWL on the Dornier MFL 5000. The mean stone volume was 1.4 cm2. Approximately one third of the patients required more than one session. The mean number of shock waves was 2010 (range 1400-3000) with a mean voltage of 20 kV (range 14-30 kV). Fragmentation was achieved in 92.6% of the patients. Only 0.4% of the sessions involved general anesthesia. At 3-month follow-up, available in 75% of the patients, the stone-free rate was 82.6%. Ureteral calculi can be treated effectively in situ by means of SWL.

A Ureteral Small Cell Carcinoma Mixed with Malignant Mesodermal and Ectodermal Elements: A Clinicopathological, Morphological and Immunohistochemical Study

A 60-year-old male with a small cell carcinoma of the right lower ureter is presented. The tumor mainly comprised a small cell carcinoma but also included a full variety of histological types such as transitional cell carcinoma, squamous cell carcinoma, adenocarcinoma, leiomyosarcoma and chondrosarcoma. Immunohistochemical staining was positive for neuron specific enolase and cluster 1 small cell lung cancer antigen/N-CAM in the small cell carcinoma and S-100 in the chondrosarcoma component. The patient underwent a right nephroureterectomy, and received prophylactic radiation of the pelvic and para-aortic lymph node regions and cisplatin and etoposide combination chemotherapy. Eight months after the chemotherapy, a transitional cell carcinoma was found in the bladder neck, and a cystectomy with urethrectomy performed. To our knowledge, this is the second report of a small cell carcinoma originating from the ureter.

High Pressure Versus Low Pressure Electromagnetic Extracorporeal Lithotripsy

A low pressure and an upgraded high pressure electromagnetic lithotriptor were compared for the treatment of calculi within the ureter. The upgrading allows for increased energy density onto the stone surface. We targeted 139 ureteral calculi (average diameter 8.1mm.) with the low pressure system. The mean number of shock waves was 7,308, 9,226 and 5,304 for calculi in the upper, mid and lower ureter, respectively, and the energy density corresponded to 0.222, mJ./mm.2, 0.224mJ./mm.2 and 0.223mJ./mm.2, respectively. Immediate fragmentation was achieved in 39 of 51 upper (77%), 21 of 42 mid (50%) and 22 of 46 lower (49%) ureteral calculi. The upgraded shock wave tube was used in 52 calculi (average diameter 6.1mm.). The mean number of shock waves was 6,250, 14,150 and 3,400 for calculi in the upper, mid and lower ureter, respectively, and the energy density corresponded to 0.32mJ./mm.2, 0.33mJ./mm.2 and 0.30mJ./mm.2, respectively. Immediate fragmentation was achieved in 11 of 16 upper (69%), 4 of 6 mid (67%) and 7 of 30 lower (23%) ureteral calculi. The communition rate did not significantly increase, which implies that the focal energy density is not the only decisive parameter in fragmentation by extracorporeal shock wave lithotripsy.

Laparoscopic ureterolithotomy for impacted lower ureteral calculi: Initial case report

A laparoscopic ureterolithotomy was performed in a 63-year-old man who presented with azotaemia and large impacted calculi in the lower ureter. Although the procedure was performed transperitoneally, the ureter was completely re-peritonealized and drained extraperitoneally.

Extracorporeal Electromagnetic Shock Wave Lithotripsy of Ureteric Stones in Situ

Between June 1989 and June 1990, 277 patients with ureteric stones were treated by the Siemens Lithostar Plus in situ. In 113 patients, the stones were in the upper third of ureter, in 51 in the midureter, and in another 113 in the lower ureter. After a mean follow-up of 32 weeks, 79% of the patients were stone free. While this figure was 85% for upper ureteric stones, it was 71 % and 76% for mid and lower ureteric stones, respectively. There was complete fragment clearance in 86% of the stones with a diameter of 1 to 10 mm (n = 140), 78% of those 11 to 20 mm (n = 118), and 32% of those larger than 21 mm (n = 19). We believe that, despite the fact that some of the stones in the present series were impacted, such high success rates justify in situ extracorporeal lithotripsy as the initial treatment of ureteric stones.

Management of Ureteral Stones by Extracorporeal Shock Wave Lithotripsy Using Lithostar Lithotriptor

In 282 patients 290 ureteral stones were treated with extracorporeal shock wave lithotripsy using the Lithostar lithotriptor. Stones were in the upper ureter in 198 units (68.3%), middle ureter in 36 (12.4%) and lower ureter in 56 (19.3%). The average stone mass was 11.9 mm. and the mean number of shock waves was 4,913 for all levels with a mean kv. of 16.9. The average number of sessions was 1.5 for all sites. Auxiliary measures in the form of ureteral catheterization were done in 24 patients (8.5%) and internal stenting in 12 (4.25%), all of whom had upper or middle ureteral stones. Disintegration of the stones was achieved in 99% of the upper, 93.7% of the middle and 91.7% of the lower ureteral stones. However, clearance of fragments within 3 months from the last session was achieved in 94.8% of the upper, 87.5% of the middle and 91.7% of the lower ureteral stones for an overall stone-free rate of 93.3%.

Extracorporeal shock-wave lithotripsy (ESWL) monotherapy for stones in lower ureter

Extracorporeal shock-wave lithotripsy (ESWL) has been accepted as the method of choice for most upper urinary tract calculi. However, in cases of stones in the lower ureter, ureteroscopic procedures have generally been preferred. Using the Dornier HM3 lithotriptor with modifications in the patient's position, we were able to successfully treat 155 unselected cases of lower ureteral calculi. The average stone size was 9.6 mm (range 5–23 mm). One hundred forty-three patients had stones located below the lower margin of the sacroiliac joint. These patients were placed in a supine position. The stones were visualized radiologically without use of a ureteral catheter in 78 percent of the patients; in 22 percent a ureteral catheter was inserted prior to ESWL to aid in stone localization. In 145 patients (94 %) treatment was completed in one session; 10 patients (6%) required two sessions. Of the patients, 38 percent were free of stones one day after ESWL; 97 percent became stone free within three months, and only 3 patients required endoscopic manipulation, after ESWL. Twelve patients had stones in the midureter overlying the sacroileum. They were placed in the prone position, and the calculi were visualized with the aid of a ureteral catheter. All these patients became free of stones one month after treatment. There were no significant treatment-related complications except for bacteremia in 1 case. In view of the remarkable efficacy, negligible complication rate, and shorter hospital stay as compared to ureteroscopic stone manipulations, we recommend high energy ESWL as the primary monotherapy of mid and lower ureteral stones.

Extracorporeal Shock Wave Lithotripsy for Ureteral Calculi

Second generation tubless lithotriptors allow for easy prone positioning of patients, resulting in increased use of extracorporeal shock wave lithotripsy (ESWL*) for calculi in the ureter, especially in the mid and lower third portions. The 3-month stone-free rate with single stones using a Dornier HM3 and a Medstone STS lithotriptor in the upper ureter was 79% (316 patients) and 81% (188), respectively, while in the mid ureter it was 60% (20 patients) and 81% (32), respectively, and in the lower ureter it was 80% (5 patients) and 85% (26), respectively. The retreatment rate with single stones using the Dornier HM3 and the Medstone STS devices was 5% and 4%, respectively, in the upper ureter, 13% and 12%, respectively, in the mid ureter, and 0% and 5%, respectively, in the lower ureter. The second procedure rate after ESWL with single stones using the Dornier HM3 and the Medstone STS units was 6% and 6%, respectively, in the upper ureter, 15% and 16%, respectively, in the mid ureter, and 0% and 17%, respectively, in the lower ureter. Expectant management is still an acceptable method to treat small ureteral stones, and it is questionable whether ESWL is the appropriate treatment for lower third ureteral stones compared to equally effective and less expensive ureteroscopy.

Minimally Invasive Ureteroscopy Using Adjustable Electrohydraulic Lithotripsy

Eighty-five ureteroscopies and electrohydraulic lithotripsies were performed using semirigid ureteroscopes of 6.5F outer diameter and probes of 2.4F and 3.3F. Prototypes of new lithotripters were employed with the option to set the energy infinitely within a range of approximately 250 mJ to 1400 mJ per pulse. Increased energy was provided by a rise in the voltage, thus modifying the peak pressure and the initial slope of the shock wave according to our previous tests. One-third of the stones were located in the upper ureter, 15% in the middle, and 46% in the lower ureter. Half of the patients had been previously treated with the Dornier MFL 5000 without success. More than 85% of the manipulations were performed under local anesthesia. Stone contact was achieved in 99%, and lithotripsy was fully successful in more than 90% with an average energy per pulse of 450 mJ. In 7%, partial disintegration was achieved, and the residual stone was flushed back into the renal pelvis and effectively treated by extracorp...

ESWL of stones in the mid-ureter.

Two hundred and twenty patients with a ureteric calculus were treated by in situ ESWL; in 60 of these the stone was located in the mid-ureter. Treatment was given without anesthesia or with sedoanalgesia only. Complete or partial stone clearance at the time of discharge from hospital was achieved in 95% irrespective of the site of the stone and there were no complications. It is suggested that in situ ESWL is effective in the treatment of stones in mid ureter as well as those in upper and lower ureter.

A study on the passage of the upper urinary tract stones after in situ ESWL

Two hundred patients with upper urinary tract stones underwent in situ ESWL with Lithostar during the recent 20 months at Kanagawa Prefectural Atsugi Hospital. Actual residual stone rates were calculated based on the period from the initiation of the treatment to the stone free status, and discussed according to the location and size of the stone treated. Total 200 patients were submitted to 1.67 +/- 0.97 treatment sessions with 6742 +/- 5545 shock waves. After 3 months, 148 patients (78%) showed stone free status, and 32 patients (16%) had residual stones less than 4 mm. The actual residual stone rates were 90.5%, 66.5%, 39.1%, 26.9% and 17.9% after 1, 3, 6, 12 and 20 weeks, respectively. The residual stone rate were lower in the lower ureter, uretero-pelvic junction, upper ureter, renal parenchyma or diverticulum and renal pelvis or calyx in order. As for the size, the larger the stones the higher the residual stone rates; the therapeutic results were significantly worse in patient group of stones larger than 21 mm compared to the patient group of smaller stones (p less than 1%). The destructed stones were passed gradually up to 6th week after in situ ESWL, however, after that fragments seldom passed out. Therefore, it was concluded that decision on the additional or combination therapeutic intervention, if necessary, should be made after 6 weeks. Combination therapy with endoscopic surgery and/or others was seemingly needed for the patients with stones of more than 21 mm in size and of renal pelvis and renal calyx to improve the rates of stone free.

Extracorporeal shock wave lithotripsy with ultrasound-guided lithostar plus.

Since 1989, the Siemens lithostar plus, an upgrade of the lithostar with the ultrasonically guided overhead module, has been available for clinical use. This unit may be used for the treatment of either biliary or urinary calculi. We report on 75 patients with urinary calculi treated between March 1989 and June 1990 with the lithostar overhead module. Stone localization showed a rate of: caliceal stones 33.5%, pelvic stones 44%, upper ureteral stones 9.3% and lower ureter stones 13%. The overall disintegration rate was 86%, with a stone-free rate after 3 months of 78%.

Anterior Pelvic Reconstruction with Ileum after Cancer Treatment

Ileum has been used to reconstruct the lower urinary tract in 15 patients (10 women, five men) after treatment for bladder or gynaecological cancer. Seven patients had previously received radical pelvic irradiation. Four methods were used: group 1 (five patients): bladder patch after partial cystectomy or bladder augmentation after clam cystotomy for bladder contracture; group 2 (four patients): bladder replacement after subtotal (supratrigonal) cystectomy; group 3 (two patients): ureteric replacement for lower ureteric obstruction or fistula, and group 4 (four patients): complete replacement of bladder and lower ureters after anterior pelvic exenteration, with creation of neovagina from caecum in the two female patients. Review of the results indicates that ileum provides a versatile and safe material for anterior pelvic reconstruction in cancer patients even after previous pelvic irradiation.

Silent Obstruction after Extracorporeal Piezoelectric Lithotripsy

Extracorporeal piezoelectric lithotripsy (EPL) is frequently used to treat renal calculi. We are presenting a case that developed silent ureteric obstruction following three sessions of EPL of 4,000 shocks each. The obstruction was silent and asymptomatic, and was detected 6 weeks later on a routine follow-up renogram. The obstruction was due to an impacted stone fragment in the lower ureter. After release of the obstruction, the kidney function did not return to pre-therapy levels due to irreversible damage. This case demonstrates the importance of doing renograms before and within a few days after shock therapy for renal stones.