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PubMed1984

Nephrolithotony: percutaneous removal of renal calculi.

The development of percutaneous nephrostomy has laid the foundation for a major advance in the treatment of urolithiasis: the percutaneous removal of renal and ureteral calculi (i.e., nephrolithotony). With the use of a variety of instruments, calculi can be either removed intact or, if too large, fragmented in situ and then extracted. The method has wide applicability; more than 90% of all upper urinary tract calculi can be successfully treated. Length of hospitalization and costs are comparable to or less than those for open surgery; however, the period of convalescence is only 2-7 days. Continued advances in fluoroscopic technology and endoscopic instrumentation will enable the urologic surgeon to treat the majority of urinary tract conditions using endourologic techniques.

Dilatation↗
PubMed1984

Percutaneous extraction of upper urinary tract calculi.

Renal calculi less than 8-9 mm in diameter and ureteral calculi of various sizes can be removed intact using fluoroscopic guidance without the need for endoscopy. Advantages of percutaneous stone extraction include a shorter hospital stay, decreased cost, and avoidance of general anesthesia. When compared with fragmentation techniques, percutaneous extraction appears to be the treatment of choice for urinary tract calculi amenable to this technique.

Anesthesia↗
PubMed2006

Biomineralogy of human urinary calculi (kidney stones) from some geographic regions of Sri Lanka.

Kidney stones (urinary calculi) have become a global scourge since it has been recognized as one of the most painful medical problems. Primary causative factors for the formation of these stones are not clearly understood, though they are suspected to have a direct relationship to the composition of urine, which is mainly governed by diet and drinking water. Sixty nine urinary calculi samples which were collected from stone removal surgeries were analyzed chemically for their Na, K, Ca, Mg, Cu, Zn, Pb, Fe and phosphate contents. Structural and mineralogical properties of stones were studied by XRD and FT-IR methods. The mean contents of trace elements were 1348 mg kg(-1) (Na); 294 mg kg(-1) (K); 32% (Ca); 1426 mg kg(-1) (Mg); 8.39 mg kg(-1) (Mn); 258 mg kg(-1) (Fe); 67 mg kg(-1) (Cu); 675 mg kg(-1) (Zn); 69 mg kg(-1) (Pb); and 1.93% (PO (4) (3-) ). The major crystalline constituent in the calculi of Sri Lanka is calcium oxalate monohydrate. Principal component analysis was used to identify the multi element relationships in kidney stones. Three components were extracted and the first component represents positively correlated Na-K-Mg-PO (4) (3-) whereas the second components represent the larger positively weighted Fe-Cu-Pb. Ca-Zn correlated positively in the third component in which Mn-Cu correlated negatively. This study indicates that during the crystallization of human urinary stones, Ca shows more affinity towards oxalates whereas other alkali and alkaline earths precipitate with phosphates.

Calcium Oxalate↗
PubMed1976

A system of interpretation of infrared spectra of calculi for routine use in the clinical laboratory.

We have devised systematic schemes for objectives qualitative analysis of the IR spectra of calculi. These schemes are presented as flow charts based on questions each requiring a yes or no answer before going on to the next step. The specific question asked in each step concerns the similarity of a limited region of the spectrum to reference spectra. For renal calculi, 5 regions are evaluated and a maximum of 10 decisions is necessary to complete the analysis. Biliary calculi are treated similarily, with 5 spectral regions evaluated and a maximum of 8 yes-no decisions required. The method requires less technician time and is much less susceptible to differences in subjective judgment than the wet chemical procedure. Three percent of stones contain unusual components and are quickly recognized as such and identified using a library of reference spectra.

Calculi↗
PubMed1991

Endourological experience with cystine calculi and a treatment algorithm.

Between May 1984 and January 1988, 18 patients (31 pyeloureteral units) with documented symptomatic cystine stones were treated. Stone size ranged from 5 to 56 mm. in largest diameter, with an average of 21 mm. All pyeloureteral units were treated initially by endourological methods, including ureteroscopy in 10, percutaneous ultrasonic lithotripsy in 9, extracorporeal shock wave lithotripsy (ESWL) in 10 and chemolysis in 2. Of the patients 10 required a combination of these technologies and 2 required an open operation. Of the 31 units 23 were free of stones when the patient was discharged from the hospital. Of 8 patients with retained stones only 3 had fragments greater than 3 mm. in diameter. Based on this experience an algorithm was developed for the urological management of cystine stones. Ureteral calculi may be removed by ureteroscopic techniques or manipulated into the renal pelvis and managed as renal stones. Cystine renal calculi of less than 1.5 cm. may be treated with ESWL monotherapy. Stones of 1.5 to 3 cm. may be treated with ESWL and dissolution, or percutaneous ultrasonic lithotripsy plus dissolution. Staghorn calculi may be treated by percutaneous ultrasonic lithotripsy plus ESWL and/or dissolution for retained fragments.

Acetylcysteine↗
PubMed1990

Electrohydraulic lithotripsy of renal and ureteral calculi.

Electrohydraulic lithotripsy was used to manage 45 upper tract calculi (23 renal and 22 ureteral stones) in 40 patients. Electrohydraulic lithotripsy successfully fragmented 91% of the calculi. All ureteral fragments cleared; in 2 patients with renal calculi solitary 4 mm. stone fragments remained. There were no intraoperative or long-term complications directly related to the use of electrohydraulic lithotripsy in the upper urinary tract. We conclude that intrarenal and intraureteral electrohydraulic lithotripsy is a safe, effective, inexpensive means to perform intracorporeal lithotripsy.

Adolescent↗
PubMed1989

First clinical experience with a Q-switched neodymium:YAG laser for urinary calculi.

Animal studies using a high intensity nanosecond pulsed neodymium:YAG laser did not reveal any serious tissue damage. Following these investigations patient treatment was begun in June 1987. Laser energy of a neodymium:YAG laser with an 8 nsec. pulse duration and a repetition rate of up to 50 Hz. was coupled into a flexible 600 resp. 400 micron. quartz fiber. Laser-induced breakdown was created with 35 to 50 mJ. at the fiber tip, resulting in a shock wave that disintegrated the calculus into tiny fragments. A total of 56 patients with 58 calculi (54 ureteral and 4 kidney stones) was treated from June 1987 to March 1988. Of the calculi 48 could be fragmented completely, while 6 others were reduced to a size small enough to be removed with forceps. Four stones composed of calcium oxalate monohydrate could not be disintegrated. The combination of laser stone disintegration with flexible ureterorenoscopy implies the possibility of an atraumatic, 1-step procedure for fragmentation of ureteral and kidney calculi.

Endoscopy↗
PubMed1985

Percutaneous removal of renal and ureteral calculi: experience with 400 cases.

Percutaneous removal of renal and ureteral calculi was performed in 500 patients since 1979. Experience with our first 100 cases enabled us to accumulate a variety of techniques. We report our experience with the subsequent 400 cases. As judged by plain films of the kidneys, ureters and bladder, and renal tomograms without contrast medium we attained a status free of stones in 99 per cent of the patients with renal and 94.5 per cent with ureteral calculi. Intravenous-assisted local anesthesia was used in 94 per cent of the cases. There was no mortality and the incidence of complications was low. Most patients with renal and ureteral calculi can be managed successfully and safely by percutaneous methods with good patient tolerance and minimal convalescence.

Adolescent↗
PubMed1984

Percutaneous nephrolithotomy: extraction of renal and ureteral calculi from 100 patients.

A percutaneous nephrostomy tract was used as a conduit to the kidney and ureter for extraction of 149 calculi in 100 patients. A variety of grasping and fragmentation techniques under fluoroscopic and endoscopic control were used to extract calculi in 88 per cent of the patients. With experience, operator efficiency and rate of stone extraction increased from 76 per cent early in the series to 91 per cent in the most recent patients, and the incidence of complications decreased from 17 to 5 per cent. Percutaneous removal of upper tract urinary calculi appears to be an appropriate alternative to an open operation in most patients with symptomatic urolithiasis.

Adult↗
PubMed2003

Endoscopic surgery for renal calculi.

PURPOSE OF REVIEW: Endoscopic surgery plays an important role in the treatment of renal calculi, especially for the more complex cases. Recent advancements have improved the efficacy of procedures, and increasing surgeon experience is associated with low complication rates. This article will review recent literature pertinent to endoscopic surgery for renal calculi. RECENT FINDINGS: Endoscopic renal calculus removal is associated with up to >90% calculus clearance rates. This is true for both retrograde and percutaneous approaches. The added utility of flexible instrumentation and holmium laser therapy have contributed greatly to improving surgical success. With increased experience in endoscopic techniques, major complications occur in approximately 1% of patients. Most procedures are performed on an outpatient (retrograde) basis or a <23 h inpatient (percutaneous) basis. SUMMARY: Endoscopic surgery is safe, and the most efficacious therapy with low morbidity for renal calculi.

Endoscopy↗
PubMed2005

Emergency drainage for urosepsis associated with upper urinary tract calculi.

PURPOSE: We examined the characteristics of patients with urosepsis associated with upper urinary tract calculi requiring emergency drainage. MATERIALS AND METHODS: From January 1994 to December 2003, 424 patients were admitted to our urological department a total of 473 times for treatment of upper urinary tract calculi, of whom 53 required a total of 59 emergency drainage procedures for urosepsis. We summarized the characteristics of these patients and events, and determined risk factors for emergency drainage using logistic regression analysis. RESULTS: In 14 events (24%) intensive management, such as the use of vasopressors and anticoagulants, was performed. Transient thrombocytopenia less than 100,000/mm occurred in 18 events (31%). Hyperbilirubinemia occurred in 8 of 38 events (16%) without prior antibiotic therapy. One patient (2%) died of urosepsis. Patients with calculi who underwent emergency drainage required a longer hospital stay than those without emergency drainage (25.2 vs 14.8 days, p <0.001). Of the variables analyzed poor performance status (Karnofsky performance status 70% or less, OR 2.9, p = 0.003), age 75 years or older (OR 2.1, p = 0.038) and female sex (OR 1.8, p = 0.046) were risk factors on multivariate analysis. CONCLUSIONS: Our findings suggest that the frequency of emergency drainage in elderly patients with poor performance status has increased in recent years, at least in our rural area of Japan. Preventing calculous formation and urinary tract infection in individuals with poor performance status will be of considerable importance in the future.

Aged↗
PubMedDate not supplied

Does ultra-low-dose CT with a radiation dose equivalent to that of KUB suffice to detect renal and ureteral calculi?

The objective of this study was to evaluate the diagnostic yield of multislice CT using a radiation dose equivalent to that of conventional abdominal x-ray (KUB). One hundred forty-two patients were prospectively examined with ultrasound and a radically dose-reduced CT protocol (120 kV, 6.9 eff. mAs). Number and size of calculi, presence of urinary obstruction, and alternative diagnoses were recorded and confirmed by stone removal/discharge or by clinical and imaging follow-up. The mean effective whole-body dose was 0.5 mSv in men and 0.7 mSv in women. The sensitivity and specificity in detecting patients with calculi was 97% and 95% for CT and 67% and 90% for ultrasound. Urinary obstruction was similarly assessed, whereas CT identified significantly more alternative diagnoses than ultrasound (P<0.001). With regard to published data for standard-dose CT, the present CT protocol seems to be comparable in its diagnostic yield in assessing patients with calculi, and its radiation dose is equivalent to that of KUB.

Adolescent↗
PubMed2005

Endoscopic treatment of multiple prostatic calculi causing urinary retention.

Although prostatic calculi are relatively common, the etiology of these stones is not clear. We report a case with multiple prostatic calculi causing urinary obstruction and a concomitant bladder stone. We treated these stones endoscopically. We found a lot of different sized stones endoscopically, some protruding into the urethra, some filling different cavities on the prostate. So these cavities suggest prostatic calculi may occur related to intraprostatic reflux in the congenital or acquired diverticulum of the prostatic tissue. In addition, the stone composition of the bladder and prostatic stones was the same. All of these results show that the origin of bladder and prostatic stones can be the same. This case also supports a theory of intraprostatic reflux and urine stasis.

Calculi↗
PubMed1990

Extracorporeal shockwave lithotripsy monotherapy for paediatric urinary tract calculi.

The role of extracorporeal shockwave lithotripsy (ESWL) in the management of paediatric urinary tract calculi was evaluated. The study group included 22 children (13 male, 9 female) with an age range of 2 to 13 years. The renal calculi, including staghorn and ureteric calculi, varied in size from 0.3 to 5 cm. Overall stone clearance at 3 months was 79% with a low incidence of complications (2 children required nephrostomy drainage for sepsis). ESWL is a non-invasive method of managing even complex stones in children of all ages, irrespective of size or position.

Adolescent↗
PubMed1975

Relationship of bacterial infection in urine and calculi to canine urolithiasis.

In 26 dogs treated surgically for urolithiasis, bacteriological examination of the urine and the interior of calculi showed that infection was present in both materials in 14 cases. Infection with phosphate calculi, present in 13 of these 14 dogs, was associated with a variety of bacteria including Staphylococcus aureus, Staph epidermidis, Streptococcus faecalis, Escherichia coli and Proteus spp. In a follow-up examination of 16 dogs, organisms different from the original isolates were recovered from some cases. The significance of the persistence of viable bacteria within canine bladder calculi is discussed.

Animals↗
PubMed1989

Ureterorenoscopy in the management of renal and ureteric calculi.

A total of 172 ureterorenoscopies were performed in 112 patients with 131 ureteric and renal calculi. The success rates for retrieval were 65, 59 and 79% in the upper, middle and lower third of the ureter, respectively. 32% of renal calculi were removed by ureterorenoscopy. By combined endourological techniques 89% of all stones were removed. Few complications occurred, and no late sequelae were recorded. It is concluded that ureterorenoscopic stone retrieval is an efficient and safe procedure, especially for lower ureteric stones. In the hand of a trained endourologist it might be attempted for upper ureteric calculi as well, and for certain renal stones in selected patients.

Adult↗
PubMed1990

Cystitis, urolithiasis and cystic calculi in ageing guineapigs.

Nineteen cases of cystitis were diagnosed at necropsy and/or by histology in a group of 170 (96 females, 74 males) guineapigs (11.2%). Seventeen of the 19 cases (89.4%) were females. The mean age of guineapigs with cystitis was 34.7 months, which was higher than the mean age of 24 months of the 170 members of the study group. In addition, 6 cases of urolithiasis and cystic calculi in 5 females and one male were also found in the 170 guineapigs (3.5%). The mean age of the 6 cases was 30 months, which was also higher than the mean age of the 170 animals. The study suggests that aged female guineapigs were much more predisposed to cystitis and urolithiasis or cystic calculi than male and young guineapigs. The cause may be related to infection with Escherichia coli and Staphylococcus sp, cystic calculi, diabetes mellitus and female guineapig urogenital anatomy and function.

Aging↗
PubMed1984

Percutaneous extraction of renal and ureteral calculi: technical considerations.

Most renal calculi up to 12 mm in diameter and most upper-ureteral calculi can be removed intact percutaneously in one stage, using fluoroscopic rather than endoscopic control. By eliminating a second-stage fragmentation procedure (e.g., ultrasonic lithotripsy), hospital stays are shortened, costs are decreased, and morbidity is lessened. The techniques for percutaneous one-stage removal of upper urinary tract calculi are described.

Fluoroscopy↗