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PubMed1984

Computed tomography and composition of renal calculi.

The attenuation values of computed tomography were studied in 50 recovered renal calculi of more than 10 mm in diameter, in the hope of determining the composition of calculi in situ. The attenuation value of various calculi (mean +/- s.d.) in a 5 mm slice with a maximal rectangular region of interest was as follows (Hounsfield units); mixed calcium oxalate and phosphate 1,555 +/- 193 (n = 22), magnesium ammonium phosphate 1,285 +/- 284 (n = 18), calcium oxalate 1,690 (n = 1), calcium phosphate 1,400 (n = 2), cystine 757 +/- 114 (n = 5) and uric acid 480 (n = 2). Attenuation values ranging from 500 to 1,600 overlapped for various calculi, except those composed of uric acid calculi. There was no correlation between the attenuation value and the mineral content such as calcium or magnesium per unit weight of calculus. The mineral content per unit volume seemed to be attributable to the attenuation value. From the present results we conclude that the determination of calculous composition by the attenuation value is possible only for oxalate calculi of more than 1,600 and uric acid calculi of less than 500 attenuation value, provided that the proper CT slice location, the region of interest and the appropriate calculus size can be determined.

Calcium Oxalate↗
PubMed2000

Sex dependence of the components and structure of urinary calculi induced by biphenyl administration in rats.

To obtain definitive information about the mechanisms of urinary calculus formation and the structural characteristics of the calculi induced by biphenyl administration in rats, with a focus on the sex dependency, the constituents of the urinary calculi were analyzed by HPLC, inductively coupled plasma spectroscopy (ICP), micro Fourier transform infrared spectroscopy (mFT-IR), and ion chromatography (IC), and structural analyses were carried out by microscopy, mFT-IR, and the electron probe microanalyzer (EPMA) method. We attempted to account for the appreciably higher incidence of calculi in males than in females. mFT-IR analysis revealed that the biphenyl-induced urinary calculi in male rats are composed mainly of potassium 4-hydroxybiphenyl-o-sulfate (4-HBPOSK), whereas the calculi in female rats are composed mainly of 4-hydroxybiphenyl (4-HBP) and KHSO(4) produced by the hydrolysis of 4-HBPOSK. Observations of photomicrographs and the results of mFT-IR analysis indicated that the calculi in males have a multilayer structure consisting of alternating layers of 4-HBPOSK and calcium phosphate, whereas the calculi in females have no multilayer structure, but open holes in which needle-shaped crystals are present in some places. In view of the results of these analyses, including the EPMA analysis, it appears that calculus formation in males may involve a series of successive and irreversible reactions, whereas calculus formation in females may result from a series of reversible reactions, including the hydrolysis of 4-HBPOSK. It was inferred that the series of irreversible reactions involved in calculus formation in males is relatively more stable than that in the case of females, and thus, a sex difference in the reaction features may be responsible for the observed difference in the incidence of calculus formation.

Animals↗
PubMed2003

Preliminary report on the correlations among pineal concretions, prostatic calculi and age in human adult males.

By using quantitative image analysis of soft X-ray photographs on the bulk of extracted pineal glands and prostates, we made a preliminary investigation into the correlations among pineal concretions (% by mass), prostatic calculi (% by mass) and age (years) in 40 human adult males, ranging in age from 31 to 95 years (mean (+/-SD) 69.9 +/- 15.2 years), who died and underwent the routine dissection course. The mass concentrations of pineal concretions and prostatic calculi were 17.68 +/- 13.56% (range 0-51.34%) and 0.93 +/- 1.31% (range 0-5.82%), respectively. There was no correlation between the mass concentration of pineal concretions and aging (r = 0.03; P < 1.0). There was no correlation between mass concentration of prostatic calculi and aging (r = 0.28; P < 0.5). No pineal concretions and no prostatic calculi were observed in seven and 10 cases, respectively; in addition, in one case, neither-concretions nor calculi were seen. From such data and from the previously reported suggestion on the counteracting functions between the pineal gland and prostate, a negative correlation between the mass concentrations of pineal concretions and prostatic calculi was expected. This was certainly obtained, but the correlation was low (r = -0.39; P < 0.05). Such a low correlation and no correlations between the concentrations of pineal concretions and aging or between prostatic calculi and aging may have been caused by the examination of relatively older humans. Therefore, further investigations using a number of pair samples collected from males including younger age generations will be necessary.

Adult↗
PubMed1998

Paediatric ureteric calculi: efficacy of primary in situ extracorporeal shock wave lithotripsy.

OBJECTIVE: To evaluate the efficacy of primary in situ extracorporeal shockwave lithotripsy (ESWL) for the treatment of ureteric calculi in children. PATIENTS AND METHODS: The Wolf 2500 Piezolith was used to treat 63 children (aged 4 months to 12 years) with 76 ureteric calculi, including 10 children with impacted calculi. The calculi were located in 14 upper, 13 mid and 44 lower ureters, and the stone burden varied from 4 to 17.8 mm (mean 12.6). All children aged < or = 10 years were treated under general anaesthesia; lithotripsy was attempted under intravenous sedation in the older children. RESULTS: At the 3-month follow-up, there was an overall successful outcome in 55 children (87%), which included 12 of 13, eight of nine (89%) and 35 of 41 (85%) of the children with upper, mid and lower ureteric calculi, respectively, and nine of the 10 with impacted calculi. Re-treatment was required in 20 (36%) patients, while auxiliary procedures after ESWL were required in three (6%). The major complications encountered were ureteric obstruction with sepsis in two children, bacteraemia in another and urinary retention due to a urethral stone fragment in a fourth child. CONCLUSIONS: In situ ESWL was an effective treatment modality for ureteric calculi at all levels in children, even when impacted. In the short term, complications were minimal, but the long-term effects need further assessment.

Child↗
PubMed1998

Holmium: YAG lasertripsy for ureteric calculi: an experience of 300 procedures.

OBJECTIVE: To assess the success of holmium:YAG lasertripsy in the management of ureteric calculi and to audit the complications of the procedure, with special reference to strictures in the ureter. PATIENTS AND METHODS: A total of 300 ureteroscopic laser procedures were carried out on 265 patients (204 male and 61 female, median age 51 years, range 2-95) with ureteric calculi. At ureteroscopy, the calculi were present in the upper ureter in 44%, mid-ureter in 37% and lower ureter in 19% of patients; most calculi were > 5 mm. A 7.5 F Wolf semi-rigid ureteroscope was used and the holmium:YAG laser energy delivered using the Sharplan ML210 device at 0.8-1.0 J/pulse. The patients were followed up at approximately 6 weeks with limited intravenous urography or ultrasonography to assess clearance and the incidence of strictures. RESULTS: Stones were completely cleared in 90% of the patients, with the best results in the lower and mid-ureter (97% and 96%, respectively) followed by the upper ureter (89%). Alternative procedures were required in only 17 (7%) patients; extracorporeal shock-wave lithotripsy in 13, percutaneous nephrolithotomy in two and open pyelolithotomy in two patients. Complications with ureteric perforation in 11 patients, including laparotomy for peritonitis in one, serious sepsis in two and strictures in 10 patients. Strictures were more common in association with impacted calculi in the upper ureter early in the series. CONCLUSIONS: Holmium:YAG lasertripsy is a highly effective treatment for ureteric calculi, with strictures related to the treatment of difficult upper ureteric calculi.

Adolescent↗
PubMedDate not supplied

Endoscopic-assisted disruption of urinary calculi using a holmium:YAG laser in standing horses.

OBJECTIVE: To describe a technique for endoscope-assisted disruption and removal of urinary calculi using a holmium:YAG laser in sedated, standing horses. STUDY DESIGN: Retrospective study. ANIMALS: Six horses with urinary calculi. METHODS: A holmium:YAG laser was used to disrupt naturally occurring urinary calculi in horses (4 geldings, 1 stallion, 1 mare). Ischial urethrotomy was performed in male horses to provide a portal for the endoscope and laser fiber. Calculus fragments were removed by a combination of lavage, transendoscopic basket snare removal, forceps, and digital manipulation. Ischial urethrotomies healed by second intention. Follow-up was obtained by recheck examination and telephone interview of owners. RESULTS: No major operative or postoperative complications occurred. Two calculi (1 stallion and 1 mare) were fragmented by a combination of laser ablation and manual disruption with a lithotrite. Postoperative dysuria occurred in the mare, but resolved after 1 month. Mean (+/- SD) follow-up was 306 +/- 149 days; no other complications were reported. CONCLUSIONS: Calcium carbonate urinary calculi (up to 15 cm in diameter) in horses can be effectively fragmented with a holmium:YAG laser. It is not known if this technique would be completely effective for larger calculi or extremely dense calculi. CLINICAL RELEVANCE: Calculus disruption by an endoscopically assisted holmium:YAG laser offers a minimally invasive method that can be performed in standing horses and that minimizes patient risk.

Animals↗
PubMed1986

Randomized trial of allopurinol in the prevention of calcium oxalate calculi.

In a double-blind study, we examined the efficacy of allopurinol in the prevention of recurrent calcium oxalate calculi of the kidney. Sixty patients with hyperuricosuria and normocalciuria who had a history of calculi were randomly assigned to receive either allopurinol (100 mg three times daily) or a placebo. After the study, the placebo group had 63.4 percent fewer calculi (P less than 0.001), whereas the allopurinol group had 81.2 percent fewer calculi (P less than 0.001). During the study period, the mean rate of calculous events was 0.26 per patient per year in the placebo group and 0.12 in the allopurinol group. When the treatment groups were compared by actuarial analysis, the allopurinol group was found to have a significantly longer time before recurrence of calculi (P less than 0.02). We conclude that allopurinol is effective in the prevention of calcium oxalate stones in patients with hyperuricosuria. The large reduction in the frequency of calculi in the placebo group underscores the positive treatment bias that regularly occurs in trials of prophylaxis against renal calculi when historical controls are used.

Allopurinol↗
PubMed2002

The Dornier Compact Delta lithotripter: the first 150 ureteral calculi.

BACKGROUND AND PURPOSE: Shockwave lithotripsy (SWL) is the least invasive treatment for ureteral calculi and is the best accepted by patients and clinicians. This prospective study was performed to evaluate the results of SWL for all ureteral calculi. PATIENTS AND METHODS: Between April 1999 and May 2000, there were 150 SWL treatments for ureteral calculi at our center. All patients who completed treatment (24 females, 126 males with an average age of 54 +/- 14 years) were entered in the study and were assessed at 1 and 3 months with a plain film of the kidneys, ureters, and bladder and an ultrasound scan or intravenous urogram if clinically indicated. The outcome has been analyzed according to stone size, location (lower ureter [LU], midureter [MU], and upper ureter [UU], number of treatments per stone, number of shocks per stone, and stone-free rate (SFR). The analgesia requirements during each treatment and complications have also been analyzed. RESULTS: The SFR in the UU was 77% at 1 month and 85% at 3 months. The SFR in the MU was 74% at both 1 and 3 months. The SFR in the LU was 65% at 1 month and 74% at 3 months. Overall, the SFR for all calculi was 72% at 1 month and 79% at 3 months. Ureteroscopic extraction was necessary in 19% of the patients and conservative management for the remaining asymptomatic fragments, which were 2 mm or smaller. All of these asymptomatic fragments were seen to have passed spontaneously on follow-up imaging studies. Ureteral stents were not placed routinely prior to SWL, but there were 32 calculi (21%) for which stents had been placed prior to SWL: 29 (19%) in the UU, 3 (2%) in the MU, and 0 in LU. There was no difference in the SFR or ureteroscopy rate in UU calculi treated with or without stents and no difference in the number of treatments needed to achieve these SFRs. The efficiency quotient for the UU was 55%, 45% for the MU, and 45% for the LU. Oral analgesia was given routinely; however, additional intravenous analgesia was necessary in 24% of treatments. No serious complications were seen. CONCLUSIONS: The Dornier Compact Delta lithotripter provides an effective noninvasive treatment for ureteral calculi that is achieved with minimal anesthesia and a low complication rate. Placement of ureteral stents prior to SWL does not enhance the SFR or obviate intervention if SWL fails. We recommend a low threshold for ureteroscopic treatment if significant progress is not made in fragmenting the stone with SWL.

Adult↗
PubMed2003

Treatment of ureteral calculi with ballistic lithotripsy.

BACKGROUND AND PURPOSE: Ballistic lithotripsy is one of the new intracorporeal lithotripsy methods. In this study, the efficacy and complications of this method in the management of ureteral calculi were evaluated. PATIENTS AND METHODS: From November 1999 to December 2001, 340 patients (mean age 39.8 years; range 1.5-82 years) with a total of 362 ureteral calculi (bilateral in 22 cases) were treated with an 8.5F rigid ureteroscope and the Swiss Lithoclast. Of the calculi, 115 (32%) were located in the upper ureter, 63 (17%) in the middle ureter, and 184 (51%) in the lower ureter. The mean stone size was 10.4 mm (range 5-22 mm). RESULTS: Nearly all (344; 95%) of the calculi were accessible with the ureteroscope, and 321 calculi (88.7%) were fragmented completely, either with no residual fragments or with residual fragments <3 mm. In 3 cases (0.8%), there were residual fragments of about 4 mm after the procedure that passed spontaneously. Twenty calculi (5.5%) migrated to the kidney during the procedure and were subsequently treated with adjuvant SWL. Major complications occurred in 2 cases (0.54%): ureteral perforation and stenosis in 1 patient each. The 2-week stone-free rate was 89.5% (324/362). CONCLUSION: Lithoclast ballistic lithotripsy is a safe and effective approach for the treatment of ureteral calculi regardless of composition.

Adolescent↗
PubMed1994

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.

Adolescent↗
PubMed2004

Progression of nephrolithiasis: long-term outcomes with observation of asymptomatic calculi.

BACKGROUND AND PURPOSE: Observation is often recommended for patients presenting with asymptomatic renal calculi. This study evaluated the natural history of asymptomatic calculi and the risk of progression of disease. PATIENTS AND METHODS: We conducted a retrospective evaluation of 300 male patients average age 62.8 years who were followed for a mean of 3.26 years for asymptomatic renal calculi in an outpatient urology clinic. At presentation, the mean cumulative stone diameter was 10.8 mm; 56% were lower-pole stones, and 48% of the patients had multiple calculi. Patients underwent annual radiographic imaging and clinic visits with standardized questions regarding the development of symptoms or complications from calculi. Progression of disease was defined as the need for surgical intervention, the development of pain, or stone growth on serial imaging. RESULTS: Overall, 77% of patients experienced disease progression, with 26% requiring surgical intervention. Stone size was positively associated with progression: those with an isolated stone >/=4 mm on presentation were 26% more likely to fail observation than patients with smaller solitary calculi (P = 0.012). Stone growth was less common in those with upper-pole and middle-pole stones (47% v 61%) for lower-pole stones; P = 0.002). Urine uric acid concentration correlated positively with the rate of stone growth (P = 0.05). Likewise, serum uric acid concentration predicted stone growth (odds ratio = 3.6). CONCLUSIONS: Stratification of risk of progression according to presenting stone size, location, and composition may facilitate discussions with the patient regarding the alternatives of observation versus intervention. Specifically, small non-uric acid calculi in the upper pole may be most amenable to observation.

Adult↗
PubMed1990

Minimally invasive treatment of ureteric calculi using modern techniques.

Between July 1985 and July 1986, 226 upper and 62 distal ureteric calculi were treated. In situ extracorporeal shockwave lithotripsy (ESWL) is the treatment of choice for upper and distal ureteric calculi, with success rates of 81 and 76% respectively. Retrograde manipulation of the calculus was undertaken only when in situ ESWL was impossible because of difficulty in localisation. Although ESWL after successful mobilisation was successful in 95% of patients, retrograde mobilisation was possible in only 80%. Antegrade ureterorenoscopy via a percutaneous nephrostomy was performed to avoid open surgery if retrograde mobilisation was not feasible, and was successful in 90%. Two second generation lithotripters, the modified Dornier HM3+ and the Wolf Piezolith 2200, both suitable for treatment without anaesthesia, were compared in terms of efficacy. In situ ESWL of upper ureteric calculi was successful in 70.6% with the HM3+ and 37.2% with the Piezolith 2200. In situ ESWL of middle ureteric calculi was successful in 81.8% with the modified HM3+, while in situ treatment of middle ureteric calculi was impossible with the Piezolith 2200 because of inadequate ultrasound localisation. Distal ureteric calculi were treated successfully in 71.4% with the modified Dornier HM3+ and in 64% with the Piezolith 2200. We report our experience of ESWL using the prone position for iliac ureteric calculi; 8 of 10 patients were treated successfully in situ.

Humans↗
PubMed1990

In situ lithotripsy of ureteral calculi: review of 261 cases.

The authors report 261 cases of single ureteral calculi treated with in situ lithotripsy after retrograde manipulations had failed. Previous reports have indicated that extracorporeal lithotripsy of impacted ureteral calculi has not been highly successful. Two hundred five of the calculi were located in the proximal ureter, above the sacroiliac joint; 27 were in the presacral ureter, overlying the bony pelvis; and 29 were in the juxtavesicular ureter, below the inferior border of the sacroiliac joint. Retrograde ureteral catheters were in place during lithotripsy for 215 calculi. Two hundred fifty-four (97%) calculi were successfully treated with lithotripsy and, when necessary, with additional postlithotripsy radiologic and urologic interventions. Seven (3%) calculi were not successfully fragmented. Nephrostomy was performed in 13 (5%) patients. Retrograde ureteral catheters were not found to enhance calculus fragmentation. In situ lithotripsy of ureteral calculi has been shown to be feasible as an alternative to ureterolithotomy when retrograde manipulation has failed.

Follow-Up Studies↗
PubMed1990

Shock wave monotherapy of staghorn calculi.

From June 1987 to October 1988, 52 staghorn calculi were treated without anesthesia by shock wave lithotripsy with the second-generation lithotriptor, Lithostar Siemens. 36 calculi were evaluated. Multiple sessions (n = 1-6) were necessary according to the size of the stone. The mean hospital stay for complete treatment was 7 days. Double-J stenting was used in 45% of the patients with calculi of less than 40 mm and in 81% of the patients with calculi of greater than 40 mm. After 3 months, 50% of the patients with calculi of less than 40 mm were free of stones, as were 43% of the patients with calculi greater than 40 mm. After 9 months, the stone-free rate rose to 75%. At 3 months, the success rate (stone free or residual fragments of less than 4 mm) is 87.5% and rose to 92% at 9 months. Two severe complications were observed: one patient with acute infected hydronephrosis with sepsis and one with perirenal hematoma. Shock wave lithotripsy monotherapy of staghorn calculi is possible in multiple treatment sessions. Double-J stenting is mandatory in most of the cases but, even in this condition, anesthesia is not necessary.

Humans↗
PubMed2006

Factors affecting calcium oxalate dihydrate fragmented calculi regrowth.

BACKGROUND: The use of extracorporeal shock wave lithotripsy (ESWL) to treat calcium oxalate dihydrate (COD) renal calculi gives excellent fragmentation results. However, the retention of post-ESWL fragments within the kidney remains an important health problem. This study examined the effect of various urinary conditions and crystallization inhibitors on the regrowth of spontaneously-passed post-ESWL COD calculi fragments. METHODS: Post-ESWL COD calculi fragments were incubated in chambers containing synthetic urine varying in pH and calcium concentration: pH = 5.5 normocalciuria (3.75 mM), pH = 5.5 hypercalciuria (6.25 mM), pH = 6.5 normocalciuria (3.75 mM) or pH = 6.5 hypercalciuria (6.25 mM). Fragment growth was evaluated by measuring increases in weight. Fragment growth was standardized by calculating the relative mass increase. RESULTS: Calcium oxalate monohydrate (COM) crystals formed on COD renal calculi fragments under all conditions. Under pH = 5.5 normocalciuria conditions, only COM crystals formed (growth rate = 0.22 +/- 0.04 microg/mg x h). Under pH = 5.5 hypercalciuria and under pH = 6.5 normocalciuria conditions, COM crystals and a small number of new COD crystals formed (growth rate = 0.32 +/- 0.03 microg/mg x h and 0.35 +/- 0.05 microg/mg x h, respectively). Under pH = 6.5 hypercalciuria conditions, large amounts of COD, COM, hydroxyapatite and brushite crystals formed (growth rate = 3.87 +/- 0. 34 microg/mg x h). A study of three crystallization inhibitors demonstrated that phytate completely inhibited fragment growth (2.27 microM at pH = 5.5 and 4.55 microM at pH = 6.5, both under hypercalciuria conditions), while 69.0 microM pyrophosphate caused an 87% reduction in mass under pH = 6.5 hypercalciuria conditions. In contrast, 5.29 mM citrate did not inhibit fragment mass increase under pH = 6.5 hypercalciuria conditions. CONCLUSION: The growth rate of COD calculi fragments under pH = 6.5 hypercalciuria conditions was approximately ten times that observed under the other three conditions. This observation suggests COD calculi residual fragments in the kidneys together with hypercalciuria and high urinary pH values may be a risk factor for stone growth. The study also showed the effectiveness of specific crystallization inhibitors in slowing calculi fragment growth.

Calcium↗
PubMed2001

Ultrastructure of selected calcium oxalate-containing urinary calculi from dogs.

OBJECTIVE: To elucidate the ultrastructural details of calcium oxalate-containing urinary calculi from dogs. Sample Population-38 specimens selected from a collection of 8,297 oxalate-containing urinary calculi from dogs: 22 specimens composed of calcium oxalate (calcium oxalate monohydrate [COM], calcium oxalate dihydrate [COD], or COM and COD) and 16 specimens composed of calcium oxalate with amorphous calcium phosphate. PROCEDURE: Analyses of specimens included use of plain, reflected, and polarized light microscopy, X-ray diffractometry, scanning electron microscopy (SEM) with backscattered electron (BSE) imagery, and electron microprobe analysis. RESULTS: Four texture types were observed in calcium oxalate calculi; 4 texture types of calcium oxalate-calcium phosphate-mixed calculi were recognized. Texture types were delineated through differences in calcium oxalate crystal sizes, which were affected by urine supersaturation and abundance of crystal nucleation sites. Segregation of calcium oxalate from calcium phosphate indicated they do not precipitate under the same conditions. Deposition of calcium phosphate between calcium oxalate crystals decreased the volume of pore spaces within calculi. Porosity was observed along boundaries between COM and COD. Minute pores increased the surface area of calculi exposed to urine, and this increase in liquid-solid interface promotes interaction of crystals with the surrounding urine. CONCLUSIONS AND CLINICAL RELEVANCE: Calcium oxalate urolithiasis is of major concern, because it is often a recurrent disease among dogs, principally treated by surgical removal of calculi, with few effective dissolution strategies. Understanding the ultrastructure and mineralogic content of calcium oxalate and its association with amorphous calcium phosphate is a step toward the solution of this increasingly important medical problem.

Animals↗
PubMed1990

Urinary tract calculi dissolved by means of renacidin. An experimental study.

Removal urinary tract calculi by surgery may be difficult in patients with poor health or in patients who have been operated on earlier. By means of percutaneous nephrostomy it is possible to irrigate the renal pelvis with Renacidin to dissolve calculi. Renacidin is a buffer and mainly consists of citrate and gluconate. The solution makes it possible to dissolve some calculi. This study was carried out in order to evaluate the influence of the concentration of renacidin and of the speed of the irrigation. Urinary tract calculi were obtained from five patients. The calculi were cut into 2 mm thick slices. Each slice was weighed before it was placed in a chamber for irrigation. Irrigation of the slices by means of renacidin was performed at speeds of 30, 60 or 120 ml/h. Slices wre also kept in vessels containing renacidin without replacing the fluid during the irrigation. In two series dissolution was investigated for various concentrations of renacidin. Elementary analysis using absorption and spectrophotometric techniques was performed and a qualitative evaluation of the distribution of the inorganic components was carried out using the microradiographic technique. The speed of the dissolution of urinary calculi varied between 0.43 and 7.7 mg/h. Two stones were easily dissolved (5 and 7.7 mg/h) while the three others were more resistant (0.5, 1.0 and 3.0). Diluted renacidin fluid (1:3) was less effective and reduced dissolution from 5.8 to 0.7 mg/h. The speed of the irrigation was of minor importance in the experimental situation. The dissolving effect of renacidin varied for different calculi.(ABSTRACT TRUNCATED AT 250 WORDS)

Citrates↗
PubMed1992

[Radiopacity of the cystine calculi on KUB].

To study the radiopacity of cystine calculi. We have compared them with oxalate and/or phosphate calculi on plain X-ray films (KUB). Eleven pure cystine calculi from 5 people in 4 families, and 8 oxalate and/or phosphate calculi as controls were obtained from patients by lithotomy or spontaneous discharge in Dokkyo University School of Medicine and affiliated hospitals, since 1978. The radiopacity of cystine calculi was measured by a densitometer PDA-60 (Konika Co.), comparing the density of the calculus with that of the area surrounding the calculus on KUB. All cystine calculi were easily recognized on KUB, and their densities were fairly identical with those of oxalate and/or phosphate calculi.

Adult↗