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At least 991 records · Page 55Linked to original sources
PubMed1987

Pulsed dye laser fragmentation of ureteral calculi: initial clinical experience.

The pulsed dye laser, emitting at wavelengths of 504 nm. for 1 microsecond. at a frequency of 5 Hz. transmitted via a 250 mu in diameter silicon-coated quartz fiber, was passed into the ureter through the working channel of a 9.5F rigid ureteroscope. Seventeen patients with ureteral calculi too large to be extracted directly, who were unable to be treated by extracorporeal shock wave lithotripsy or who otherwise would have required transureteral or percutaneous ultrasonic stone removal, underwent attempted stone fragmentation by pulsed dye laser application. Of the 17 calculi 16 were fragmented to spontaneously passable or easily extractable fragments. There was no significant ureteral injury, thermal or otherwise, attributable to laser energy action. At 3-month followup 15 of the 17 ureters had improved and 2 showed evidence of ureterscopic injury. The mechanism of stone fragmentation by laser is small volume "shock wave" formation.

Coloring Agents↗
PubMed1986

Combined percutaneous and extracorporeal shock wave lithotripsy for staghorn calculi: an alternative to anatrophic nephrolithotomy.

Combinations of percutaneous and extracorporeal shock wave lithotripsy were performed on 46 patients with 52 staghorn calculi. Of the renal units 15 per cent had minute residual fragments but only 9.7 per cent with struvite had residual stones. The morbidity of this combined approach is less than that of anatrophic nephrolithotomy. We believe that the majority of staghorn calculi can be removed in this manner. Nephrostolithotomy should be the initial procedure in most instances. This less invasive approach is especially advantageous in patients at high risk for recurrence.

Adolescent↗
PubMed1986

Combined treatment of branched calculi by percutaneous nephrolithotomy and extracorporeal shock wave lithotripsy.

Eighty-seven patients with branched renal calculi were treated by a combination of percutaneous nephrolithotomy and extracorporeal shock wave lithotripsy. Stone debulking was achieved by percutaneous nephrolithotomy and residual stone fragments were destroyed by shock wave lithotripsy. Of the patients 70 (80 per cent) required 2 to 3 treatments, 12 (14 per cent) required 4 treatments and 5 (6 per cent) required 5 to 6 treatments. Results after 3 months indicated that 58 patients were free of stones, 3 had recurrent stones and 12 had disintegrated stone particles (less than 3 mm.) in the collecting system, while 13 were lost to followup. One patient had undergone nephrectomy. This treatment plan minimized the disadvantages of either technique when used alone and made open operative intervention unnecessary. Procedural and fluoroscopy times were reduced drastically compared to reported data on percutaneous nephrolithotomy only. We believe that more than 90 per cent of all branched calculi can be treated with this combined technique.

Adolescent↗
PubMed1985

Experimental observations on dissolution of uric acid calculi.

An in vitro model was devised to evaluate the efficacy of the different irrigating solutions utilized for local dissolution of uric acid stones. Tris (hydroxymethyl) aminomethane proved to be several times faster than sodium bicarbonate in dissolving uric acid calculi. The maximal dissolution rate was obtained when the highest pH (10.5) of Tris buffer was used in concentrations at or above 0.2 M. This makes the commercially available THAM-E an optimal choice. Stones averaging 1 cm. in diameter were dissolved in less than 48 hours when this compound was used. Sodium bicarbonate should only be used in solutions with concentrations lower than 0.2 M and pH below 9, if some dissolution is to be attempted. Concentrations and pH's above these levels will coat the stones with hard shells of sodium urate, making it impossible to dissolve them. The in vitro findings were confirmed in vivo in a limited study in pigs with human uric acid calculi surgically placed in their kidneys. Our results indicate how to make the best use of the solutions clinically available in order to obtain total dissolution of uric acid stones in short periods of time. We recommend the use of a 0.3 molar concentration of this buffer (THAM-E) at flow rates of about 50 cc per hour.

Animals↗
PubMed1984

Primary dissolution therapy of struvite calculi.

Percutaneous nephrostomy and hemiacidrin were used as primary treatment of magnesium ammonium phosphate calculi in 32 surgical candidates. Of 28 patients who actually received hemiacidrin 24 (85 per cent) had successful treatment (no surgery necessary), including 19 (68 per cent) who had total stone dissolution. There were no significant complications. Patients have been followed for 3 months to 7 years. Percutaneous nephrostomy with hemiacidrin infusion is another possible treatment in the growing alternatives available for patients with urinary struvite calculi.

Citrates↗
PubMed1982

Dissolution of cystine calculi by pelviocaliceal irrigation with tromethamine-E.

We report 3 cases of cystine calculi. The stones were dissolved by pelviocaliceal irrigation with tromethamine-E, performed either through a percutaneous nephrostomy tube or ureteral catheters. The 25, 27 and 37-day courses of irrigation were well tolerated by all patients. Complications included a single asymptomatic urinary tract infection that required antibiotic therapy and transient hematuria due to catheter irritation. Our experience demonstrates that cystine calculi, including staghorn, can be dissolved by tromethamine-E irrigation, thereby obviating the need for surgical intervention.

Adolescent↗
PubMed1980

A crystallographic study of prostatic calculi.

We analyzed 70 prostatic calculi using crystallographic methods and determined the individual composition of the layers, structures and ultrastructures, thus, obtaining a more precise classification of these calculi.

Apatites↗
PubMed1980

Adjuvant surgical techniques in the removal of staghorn calculi.

Surgical removal of staghorn calculi can be difficult. We describe a retrospective review of 21 patients who underwent 22 operations for the removal of staghorn calculi. Subsequent urinary infections occurred in 30 per cent and recurrent stones developed in 20 per cent of the patients. We emphasize the accuracy and importance of intraoperative roentgenography, the usefulness and morbidity of hemiacidrin irrigation and the postoperative stability of renal function measured by a radionuclide renal function test.

Adult↗
PubMed1979

Ultrasound evaluation of bladder calculi.

A case is presented in which the identification of intravesical calculi by ultrasound was an aid in management. Bladder stones appear as high intensity echoes within the bladder, have an associated acoustic shadow and shift to the dependent portion of the bladder with alterations in position. Ultrasound provides a rapid, safe imaging technique to diagnose or verify the presence of bladder calculi.

Child, Preschool↗
PubMed1979

Directional growth of renal calculi.

The forces involved in shaping urinary calculi reside in crystalline characteristics and especially in local influences. Box pleves may restrict passage and, by allowing mobility, help shape a round calculus. Fixation, occurring with a rapidly growing infection stone, facilitates initial growth on a matrix mold in a funnel pelvis, further aided by pelviocaliceal paralysis from bacterial endotoxins and later by stasis. Branched calculi are further shaped by contact with the pelvic and infundibular walls. Through pressure and mucous coating they grow only at the ends. Late caliceal obstruction frees the ends for clubbing. Consideration of these forces aids in prognosis and surgical removal, and may offer opportunities for prevention.

Calcium Oxalate↗
PubMed1977

Staghorn calculi in children.

Nineteen children who underwent extensive nephrotomies and anatrophic nephrotomies for staghorn calculi (bilateral in 4 cases) are presented. Proteus infection was the cause of the calculus in most cases. In the absence of recurrent stones, renal growth and function were excellent post-operatively. Stone recurrence was minimal if all calculi were removed and infection was controlled. Followup ranged from a few months to 13 years.

Adolescent↗
PubMed1977

The localization of intrarenal calculi during surgery.

This is a summary review of past and present technology for accurate anatomical localization of calculi within the surgically exposed kidney. The methodology is applicable to reconstructive renal surgery for pathological processes other than calculi.

Fluoroscopy↗
PubMed1976

The surgical fate of ureteral calculi: review of Mayo Clinic experience.

A review of 1,061 patients who underwent ureterolithotomy of transurethral manipulation revealed 2 factors that are important to consider; 1) the roentgenographic size of the calculi measured at the largest diameter and 2) the location of the calculus. These 2 facotrs in addition to the general medical condition of the patient, the duration of severity of symptoms and the status of the upper urinary tract provide suitable guide lines for individual management of ureteral calculi.

Adolescent↗
PubMed1976

Dissolution of residual renal calculi with hemiacidrin.

Hemiacidrin irrigation of the renal collection system via nephrostomy for the dissolution of residual postoperative calculi is described in 14 cases. The irrigation successfully dissolved 13 to 16 caliceal calculi. It did not dissolve any parenchymal calcifications. No known stones of pure calcium oxalate or apatite have been dissolved. Residual stones can safely be dissolved with hemiacidrin irrigation via nephrostomy if clear open drainage and scrupulously sterile urine are maintained.

Adult↗
PubMed2000

Intensive medical management of ureteral calculi.

OBJECTIVES: To compare two treatment regimens in patients with ureteral calculi. One regimen (control arm) used routine drugs, and the second regimen (treatment arm) used the same routine drugs plus uncommonly used drugs. METHODS: Between February and October 1998, 70 consecutive patients were evaluated for symptomatic ureteral calculi. Thirty-five patients were randomized to a control arm and received ketorolac, oxycodone, and acetaminophen combination tablets and prochlorperazine suppositories. Thirty-five patients were randomized to the treatment arm and received the same medications plus nifedipine XL, prednisone, and trimethoprim/sulfa combination tablets and plain acetaminophen. Stone passage rates, work days lost, emergency room visits, surgical interventions, and possible side effects of the drugs were recorded. RESULTS: The treatment arm (addition of nifedipine XL, prednisone, trimethoprim/sulfa, and plain acetaminophen) had higher (86% versus 56%) stone passage rates and fewer lost work days (mean 1.76 versus 4.9), emergency room visits (1 versus 4), and surgical interventions (2 versus 15). Both arms exhibited similar potential drug side effects. CONCLUSIONS: The addition of a calcium channel blocking agent, steroids, antibiotics, and more acetaminophen effected a higher stone passage rate and fewer lost work days, emergency room visits, and surgical interventions.

Absenteeism↗
PubMed2001

Impact of power index, hydroureteronephrosis, stone size, and composition on the efficacy of in situ boosted ESWL for primary proximal ureteral calculi.

OBJECTIVES: The efficacy, safety, feasibility, and outcome of in situ treatment applied to select proximal ureteral calculi was assessed and analyzed with a view to avoiding auxiliary interventions and providing high clearance rates in the shortest possible time. We studied the impact of several clinically important variables, including power index, degree of hydroureteronephrosis (HDUN), stone size, and composition on the efficacy of sequential in situ boosted extracorporeal shock wave lithotripsy (ESWL) in a select group. The power index requirement for the in situ boosted protocol and the impact of the stone size/composition, degree of HDUN, and clearance rates were also analyzed. METHODS: An in situ (no instrumentation) boosted protocol was applied to 130 primary unimpacted proximal ureteral calculi with no prior intervention. A typical session with the Siemens Lithostar Plus comprised 3000 shock waves, in installments of 500, deployed at a power setting of 1 to 4 kV with a gradual stepwise escalation. Sequential boosted additional sessions of ESWL were administered on days 2, 7, and 14, tailored to the degree of fragmentation, clearance status, and amount of residual stone bulk. Several parameters (shock waves, kilovolts used, fluoroscopy time, number of sessions, stone size, composition, fragmentation, clearance, and HDUN) were recorded and the results analyzed statistically. RESULTS: The results were excellent in 83.8%, with a mean duration to complete clearance of 11.3 days. In situ ESWL failed in 7.69%, and the auxiliary intervention rate was 10.7%. Pre-ESWL HDUN was present in 78.3%, the mean power index was 184.6/session/case, and the average stone burden was 8.9 mm(2). Calcium oxalate monohydrate was the most common stone (56%). Renal colic was the most common side effect observed. The power index, fragmentation at the first session, and stone size were found to be the most favorable significant variables affecting stone clearance. The degree of HDUN, number of sessions, and stone composition did not significantly impact the clearance rates. CONCLUSIONS: In situ boosted ESWL should be the first-line therapeutic modality in select unimpacted primary proximal ureteral stones.

Adolescent↗
PubMed2002

Ureteroscopy and holmium:YAG laser lithotripsy: an emerging definitive management strategy for symptomatic ureteral calculi in pregnancy.

OBJECTIVES: To review the results of holmium laser lithotripsy in a cohort of patients who presented with symptomatic urolithiasis in pregnancy. Symptomatic urolithiasis in pregnancy that does not respond to conservative measures has traditionally been managed with ureteral stent insertion or percutaneous nephrostomy. Holmium:yttrium-aluminum-garnet (YAG) laser lithotripsy using state-of-the-art ureteroscopes represents an emerging strategy for definitive stone management in pregnancy. METHODS: A retrospective analysis was conducted at two tertiary stone centers from January 1996 to August 2001 to identify pregnant patients who were treated with ureteroscopic holmium laser lithotripsy for symptomatic urolithiasis or encrusted stents. Eight patients with a total of 10 symptomatic ureteral calculi and two encrusted ureteral stents were treated. The mean gestational age at presentation was 22 weeks. The mean stone size was 8.1 mm. The stones were located in the proximal ureter/ureteropelvic junction (n = 3), midureter (n = 1), and distal ureter (n = 6). RESULTS: Complete stone fragmentation and/or removal of encrusted ureteral stents were achieved in all patients using the holmium:YAG laser. The overall procedural success rate was 91%. The overall stone-free rate was 89%. No obstetric or urologic complications were encountered. CONCLUSIONS: Ureteroscopy and holmium laser lithotripsy can be performed safely in all stages of pregnancy, providing definitive management of symptomatic ureteral calculi. The procedure can be done with minimal or no fluoroscopy and avoids the undesirable features of stents or nephrostomy tubes.

Adult↗
PubMed1991

Treatment of staghorn calculi with extracorporeal shock-wave lithotripsy and percutaneous nephrolithotomy.

Between August 1983 and August 1987, 72 staghorn calculi were treated in 66 patients. Treatment was with percutaneous nephrolithotomy (PCNL) in 30, extracorporeal shock-wave lithotripsy (ESWL) in 18, combination PCNL-ESWL in 23, and nephrectomy in 1. Complications occurred in 59 percent of patients and were twice as common after PCNL as after ESWL. Radiologic follow-up on 69 kidneys (97%) showed 58 percent were stone-free, 15 percent had residual sand or matchheads less than 5 mm, 17 percent had residual fragments of 5-15 mm, and 10 percent had greater than 15 mm residual stone burden. With a mean follow-up of thirty months, 2 of 40 stone-free patients had persistent asymptomatic Proteus urinary tract infections, and 4 of 22 patients with residual calculi less than or equal to 15 mm required additional operative treatment.

Combined Modality Therapy↗