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PubMed1991

The impact of extracorporeal piezoelectric lithotripsy on the management of ureteric calculi: an audit.

The presentation and management of 153 patients with ureteric calculi requiring active treatment over a 12-month period were reviewed; 74% of patients had primary ureteric calculi and 26% had ureteric calculi composed of fragments resulting from extracorporeal piezoelectric shockwave lithotripsy (EPL) to renal calculi; 32 patients (21%) had more than 1 calculus or a steinstrasse. The primary procedures included were in situ EPL (n = 54), push-bang (44), retrograde ureteroscopy (40), Dormia basket extraction (6), push-pull (1), antegrade ureteroscopy (1) and combinations of these (7). The success of the primary procedure could not be predicted from stone size, site or duration in the ureter, but upper tract dilatation was significantly less (p less than 0.01) in the successful group. The overall success rate for complete stone extraction was 97%, but 54 patients (35%) required more than 1 procedure to achieve this. In situ EPL and push-bang, as either primary or secondary procedures, were successful in treating 79 patients (52%); 2 patients required ureterolithotomy (1.3%). The overall complication rate was 18%. Since EPL is only successful in treating approximately half of ureteric calculi, a range of other treatments should be available to maintain a low rate of open surgery.

Adolescent↗
PubMed1991

Staghorn calculi--long-term results of management.

We have treated 167 patients with staghorn calculi. Conservative therapy was used in 61 patients who have been followed up for 1 to 18 years (average 7.8). Chronic renal failure occurred in 22 of these patients and 7 died from uraemia. The causes of chronic renal failure were bilateral staghorn calculi, staghorn calculi and contralateral urinary calculi, and chronic pyelonephritis of the contralateral kidney. The morbidity and mortality rates following conservative treatment were higher than those following surgical management. The pathological findings in 47 kidneys after nephrectomy showed severe hydronephrosis, renal abscess and xanthogranulomatous pyelonephritis. These results indicated that staghorn calculi destroyed the kidney and early complete removal of these stones is advisable.

Adolescent↗
PubMed1991

Presentation and management of urethral calculi.

A total of 36 patients with urethral calculi are presented; 34 were males, aged 2 to 65 years (mean 43). Eight patients were under the age of 6 years and presented with retention of urine. Calculi were in the posterior urethra in 56% of the patients, 33% had associated urinary tract calculi, and 47% had other diseases of the lower urinary tract, the commonest being posterior urethral stricture (42%). Of these calculi, 58% could be manipulated endoscopically into the urinary bladder, then crushed. Associated urethral strictures were dealt with by visual internal urethrotomy before manipulating the calculi. Other methods of treatment and their complications are discussed.

Adolescent↗
PubMed1993

Extracorporeal shock wave lithotripsy for ureteric calculi with the Dornier MFL5000 lithotriptor at a multi-user centre.

We have reviewed 241 consecutive cases of ureteric calculi managed with the Dornier MFL5000 lithotriptor. The patients were individually managed by 24 visiting urologists between October 1990 and September 1991. There were 153 cases of upper ureteric calculi, of which 59 were successfully manipulated back to the renal pelvis prior to treatment, and 94 were treated in situ. There were 27 mid-ureteric and 61 lower ureteric cases; in 51% of stones treated in situ ureteric stents were placed prior to extracorporeal shock wave lithotripsy. All stones were radio-opaque and localised with on-line fluoroscopy. The outcome of treatment was assessed at 3 months, with failure defined as residual calculi > or = 4 mm. The follow-up rate was 89%. The overall fragmentation rate after a single treatment was 72%, which increased to 81% with re-treatment. Of the upper ureteric calculi, manipulated stones had a significantly higher fragmentation rate (85%) compared with in situ stones (63%). The fragmentation rate was 89% for mid-ureteric stones and 71% for lower ureteric stones. Factors that significantly influenced fragmentation were retrograde manipulation of stone, number of impulses delivered and age of the patient. Stone size, the presence of a ureteric stent and mode of anaesthesia did not significantly influence fragmentation. These results suggest the Dornier MFL5000 lithotriptor is effective for the management of ureteric calculi in a multi-user setting.

Adolescent↗
PubMed1975

Crystalline structure of salivary calculi. A microradiographic and microdiffractometric study.

The crystalline substances localized in different areas of salivary calculi were identified by using microradiographic and X-ray microdiffractometric techniques. All 19 calculi analyzed had a general pattern of apatite which was recognizable both in the center and at varying distances from the core. In addition to apatite patterns, six of the calculi gave a diffraction pattern of whitlockite, which in all but one case was located in the central part of the calculi. The influence of various factors on the distribution of the crystalline substances of apatite and whitlockite within the calculi is discussed.

Apatites↗
PubMed1987

Prostatic calculi.

The presence of calculi in 300 whole prostates from consecutive autopsies were investigated by the Faxitron imaging technique. Calculi were found in 99% of the prostates, their number and size increasing with age. They were mainly localized in the ducts in the borderzone between the middle lobes and the periferal prostate posterolaterally, but often some were also found anteriorly in the centreline. Calculi were never seen in the middle lobes. We found no statistically significant relation between the number, size or localization of calculi and other morphological or pathological parameters. Prostatic calculi seem to be a part of the normal process of aging, and do in only exceedingly rare cases assume any clinical importance.

Adolescent↗
PubMed1997

Accuracy of detection and measurement of renal calculi: in vitro comparison of three-dimensional spiral CT, radiography, and nephrotomography.

PURPOSE: To compare accuracy of three-dimensional (3D) spiral computed tomography (CT) performed without administration of contrast material with that of radiography and linear nephrotomography in detection and measurement of renal calculi. MATERIALS AND METHODS: Fifty renal calculi within an abdominal phantom were imaged with 3D spiral CT, radiography, and linear nephrotomography. Spiral CT data were analyzed with workstation-based 3D imaging software, with a thresholding procedure based on the maximally attenuating voxel within each calculus during measurement. Measurement accuracy and detection rates were compared according to modality. Conventional and magnification-corrected measurements from radiography and linear nephrotomography were included. RESULTS: Spiral CT depicted calculi and allowed determination of the collective two-dimensional and 3D linear measurements statistically significantly more accurately than the other techniques; the mean linear measurement errors along individual axes did not exceed 3.6%. With 3D spiral CT, calculus volumes were determined with a mean error of -4.8%. CONCLUSION: 3D spiral CT enabled highly accurate determination of the volumes and all three linear dimensions of renal calculi. In addition, 3D spiral CT depicted calculi more sensitively than traditional techniques and provided new information and improved accuracy in the evaluation of nephrolithiasis.

Bias↗
PubMed2000

Interventional radiology in the removal of salivary calculi.

PURPOSE: To prospectively investigate the efficacy of a wire basket extractor in the retrieval of salivary calculi and establish selection criteria for suitable cases. MATERIALS AND METHODS: Twenty-five consecutive patients (14 male, 11 female; age range, 13-69 years) with salivary calculi (20 submandibular, five parotid) were treated by using a commercially available wire basket extractor with intermittent fluoroscopic guidance. RESULTS: Elimination of calculi was accomplished in 10 (40%) cases. In an additional seven (28%) cases, either part of the calculus was removed or whole calculi were removed with others remaining. Failure to retrieve any stone occurred in eight (32%) cases. The most common cause of failure was attachment of the calculus to the duct wall. CONCLUSION: Interventional radiology provides a useful adjuvant method of calculus removal and complements extracorporeal lithotripsy. Basket retrieval of calculi has low morbidity and is rapid and less invasive than traditional surgery. It is most effective in retrieving mobile stones in the extraglandular parotid and submandibular ducts.

Adult↗
PubMed2005

Multi-tract percutaneous nephrolithotomy for large complete staghorn calculi.

INTRODUCTION: The treatment of large complete staghorn calculi requires a sandwich combination of percutaneous nephrolithotomy (PCNL) and shockwave lithotripsy (SWL) or sometimes open surgery. Many urologists hesitate to place more than 2-3 tracts during PCNL because of the belief that this may increase complications. We present data to support multi-tract PCNL for large (surface area >3,000 mm(2)) complete staghorn calculi. PATIENTS AND METHODS: From July 1998 to October 2003, 121 renal units (103 patients) with large complete staghorn renal calculi were treated with PCNL. All procedures were performed in the prone position after retrograde ureteral catheterization. Fluoroscopy-guided punctures were made by the urologist followed by track dilation to 34 french. When multiple tracts were anticipated all punctures were usually made at the outset and preplaced wires were put into the collecting system or down the ureter. Stones were fragmented and removed using a combination of pneumatic lithotripsy and suction. Postoperative stone clearance was documented on X-ray KUB. RESULTS: 121 renal units of 103 patients (15 women and 88 men, mean age 43 years) were treated. Six patients had associated bladder calculi that were treated simultaneously. The stone surface area was 3,089-6,012 (mean 4,800) mm(2). 10 patients (9.7%) had renal insufficiency with a mean (range) serum creatinine of 3.0 (1.5-5.5) mg/dl. The number of tracts required per patient were 2 tracts in 11, 3 tracts in 68, 4 tracts in 39, and 5 tracts in 3, giving a total of 397 tracts in 121 renal units, over a total of 140 procedures (including second-look procedures in 19 renal units). The points of entry of these tracts were 121 upper calyx (30.4%), 178 middle calyx (44.8%), and 98 lower calyx (24.6%). All 121 units had one upper polar access tract of which 92 (76%) were supracostal. Complications were blood transfusion (n = 18), pseudoaneurysm (n = 2), fever (n = 22), septic shock (n = 1) and hydrothorax (n = 3). PCNL monotherapy achieved an 84% complete clearance rate that improved to 94% with SWL in 8 renal units with small residual fragments. Stone compositions were calcium oxalate (91%), uric acid (2%) and mixed (7%). CONCLUSION: Aggressive PCNL monotherapy using multiple tracts is safe and effective, and should be the first option for massive renal staghorn calculi.

Adult↗
PubMed1993

Total blood and urine protein of urolithiasis patients with renal calculi of different chemical composition.

We determined total blood protein (TBP) and total urine protein (TUP) in healthy subjects and urolithiasis (UL) patients with renal calculi of different chemical composition: phosphate (CaP), oxalate (CaOx) and urate (HUr). We discussed the peculiarities of TBP and TUP distribution curves obtained and showed that the data on TBP and TUP do not make it possible to reliably single out patients with UL or determine the chemical composition of calculi in their kidneys. However, it was established that the comparison of TUP measurement results for UL patients using the Ponseau-S and sulfosalicylic acid methods makes it possible to reliably separate patients with Ca-containing calculi (CaP and CaOx) from those with HUr calculi. The explanation to this phenomenon using the data on the fractional composition of TUP and the organic matrix of those patients' calculi is given.

Azo Compounds↗
PubMed1997

Indications for open stone removal of urinary calculi.

In a retrospective study we analyzed patients undergoing open stone removal in the Department of Urology of the University of Tübingen. In 2.7% of all urinary calculi, open stone surgery was necessary. Open operation was performed on all patients with complete staghorn calculi as well as on patients with renal pelvic stones and simultaneous morphological obstruction. Partial staghorn calculi were operated on only after endoscopic treatment had failed. Small renal pelvic stones and ureteral stones were surgically removed only after extracorporeal shock wave lithotripsy (ESWL) and endoscopic surgery had been unsuccessful. The treatment of choice for ureteral calculi is ESWL. If ESWL is impossible, an endoscopic approach is advisable. Open operations of ureteral calculi only have to be performed if endoscopic therapy has failed or if there is a simultaneous morphological obstruction. Meta-analysis of publications from 1981 to 1995 confirmed our approach regarding indications for open stone removal. Comparison of the results reported in the literature is very difficult because of the missing, but generally accepted definition of stone free. In addition different examination techniques to determine the status 'stone free' make it difficult to compare the various studies.

Endoscopy↗
PubMed1993

New aspects on the composition, structure and origin of calcium oxalate monohydrate calculi.

In this paper a thorough study on the composition and structure of calcium oxalate monohydrate (COM) papillary calculi is presented. In 86.4% of these calculi, small amounts of phosphates were detected and generally located at the calculi core. This demonstrates the importance of phosphates as the heterogeneous nucleus of 'pure' COM calculi. Study of the main biochemical parameters of these patients showed that the most frequent biochemical alteration was associated with hypocitraturia (25%), whereas hypercalciuria and/or hyperoxaluria were detected in very few cases. With respect to the urinary pH values, 70% of the patients presented values lower than 6 and 30% higher than 6. These facts indicate that in a number of cases the formation of phosphates is not the result of persistent high urinary pH values, and the presence of occasional papillary microinfections must be suspected. It is clear that, by avoiding the formation of heterogeneous phosphate nuclei, 'pure' COM calculi would not develop, and consequently therapies for these individuals under these conditions must take this into account.

Calcium↗
PubMed2001

Urinary calculi on computed radiography: comparison of observer performance with hard-copy versus soft-copy images on different viewer systems.

OBJECTIVE: The purpose of this study was to compare observer performance for detecting urinary calculi using abdominal computed radiography with hard-copy versus soft-copy images and with a high-resolution video monitor versus a liquid-crystal-display (LCD) monitor. MATERIALS AND METHODS: We compared observer performance for detecting urinary calculi using three sets of radiographs-hard-copy images, soft-copy images displayed on a LCD monitor (1280 x 1024 bits), and soft-copy images displayed on a high-resolution video monitor using receiver operating characteristic curve analysis with a continuous rating scale. Computed radiography was archived with a 2140 x 1760 pixel resolution and a 10-bit depth. The selected data set included 62 images: 27 images showing proven urinary calculi smaller than 6 mm and three in number, and 35 images containing no proven abnormalities. Eleven radiologists (three genitourinary radiologists and eight general radiologists) participated in the study. Interpretations of three sets of randomly distributed radiographs were performed individually in three separate sessions at 1-week intervals. RESULTS: No statistically significant differences were found in the area under the receiver operating characteristic curve for detecting urinary calculi or in the interpreting times between soft-copy and hard-copy images; the mean areas under the receiver operating characteristic curve of hard-copy images, soft-copy images displayed on an LCD monitor, and soft-copy images displayed on a high-resolution video monitor were 0.579, 0.610, and 0.732, respectively. However, soft-copy images showed relatively improved diagnostic accuracy among less experienced radiologists (p < 0.05). CONCLUSION: For detecting urinary calculi, soft-copy images offered a diagnostic accuracy similar to or slightly more accurate than that of hard-copy images obtained in a laser-printed film-based environment. The diagnostic performance with soft-copy images viewed on an LCD monitor was comparable to that of soft-copy images viewed on a high-resolution video monitor.

Data Display↗
PubMed1984

The morphology of salivary calculi. A scanning electron microscopic study.

Salivary calculi are a common disorder in the submandibular gland duct system, but the etiology and pathogenesis of the concrements remain unclear. Ten submandibular gland calculi were examined in a scanning electron microscope after critical-point drying, fracturing, and gold coating. The surface of the calculi was built up of numerous knobs covered by a smooth and occasionally filamentous substance, probably of mucinous origin. Microorganisms were commonly found at the surface. The nuclei of the calculi, which were rather homogeneous, were surrounded by lamellated structures. Between the lamellae spheroid bodies, 20-100 microns in diameter, were present. These spheroid bodies are probably of mucinous origin, which together with an amorphous granulated substance builds up the matrix. Microorganism-like structures occasionally appeared at the interface between lamellae. Microorganisms can be an important factor by providing an organic matrix in the later phase of the pathogenesis of salivary calculi. However, the nuclei did not show morphological evidence of any particular factor explaining the etiology of salivary calculus.

Bacteria↗
PubMed2002

An observational study of staghorn calculi in south Sri Lanka.

OBJECTIVES: To ascertain patient characteristics, management strategies and outcome of patients with staghorn calculi in southern Sri Lanka. METHODS: All patients with staghorn calculi seen at the urology unit in a teaching hospital during a period of eighteen months were included in this prospective study. Data in relation to patient demography, investigations, treatment and postoperative complications were collected. RESULTS: There were 60 patients with a mean age of 54 years. Eight (13%) of them were female. Urine pH was less than 7.0 in 52 (87%) patients. Urine culture was positive for bacteria in four (7%) patients. 58 patients underwent open surgery, and two patients were managed non-operatively. Seven (12%) patients developed postoperative complications. CONCLUSIONS: Staghorn calculi elsewhere are usually commoner in females and associated with alkaline urine. But in our study there was a clear male preponderance (M:F = 6.5:1), and urine pH was alkaline in 8 (13%) patients only. Hence the aetiological factors for staghorn calculi in Sri Lanka appear to be different. Although open surgical procedures which form the mainstay of treatment of staghom calculi in Sri Lanka can be performed safely and effectively, there is a necessity to provide minimal access surgical facilities.

Female↗
PubMed1991

Magnetic resonance imaging of renal calculi: an in vitro study.

Extracorporeal shock wave lithotripsy (ESWL) has been established as a standard method of urinary stone treatment. Poor fragmentation with an increased rate of complications has been noticed with certain calculi types (calcium oxalate monohydrate and cystine). In devising appropriate pre-operative strategies, it would be useful to know the calculi composition. We have investigated the in vitro utility of using magnetic resonance imaging (MRI) in analyzing urinary calculi. Our in vitro analysis found no difference in signal characteristics between calculi of varying composition. The absence of signal can be understood from a molecular basis. We conclude that MRI will not offer any assistance in characterizing the composition of urinary calculi.

Humans↗
PubMed1999

The impact of contemporary bladder management techniques on struvite calculi associated with spinal cord injury.

OBJECTIVE: To evaluate the incidence, risk factors and complications of upper tract struvite calculi, often associated with spinal cord injury (SCI), as such patients have a high incidence of urinary infection complicating their neurogenic voiding dysfunction, by reviewing a large population of patients with SCI in whom modern techniques of bladder management were used. PATIENTS AND METHODS: Between 1982 and 1996, 1669 patients with SCI were admitted to our institution; 1359 of these patients sustained their injuries during the study period. During this time, their bladder management was based on urodynamic and imaging criteria, using techniques such as early intermittent catheterization, sphincterotomy and bladder augmentation where possible to create a catheter-free, low-pressure reservoir. All instances of upper tract struvite calculi in this population were documented. Risk factors for stone development, presentation and complications, management and recurrence rates were assessed. RESULTS: Over the 15 years, 58 patients (3.5% of the SCI population) were treated for a total of 144 episodes of struvite calculi. The incidence of stones in those injured since 1982 was 1. 5%; 67% of these patients had complete spinal cord lesions, 54% had lesions of the cervical cord and 53% developed their first stone >10 years after injury. Only 22% presented within 2 years of injury. The group of patients developing stones had a significantly higher incidence of indwelling catheters (49%), bladder stones (52%) and vesico-ureteric reflux (28%) than those who were stone-free. The development of recurrent urinary tract infections was the most common mode of presentation. The stone-free rate after treatment was 87%. Normal renal function was preserved in 72% of patients. CONCLUSIONS: In a large population of patients with SCI managed using contemporary bladder techniques the incidence of upper tract calculi was 3.5%; 30% of these stones were complete or partial staghorns. Those patients with complete cord lesions, permanent indwelling catheters and vesico-ureteric reflux were at the highest risk. Stone clearance was 87% and recurrent stones occurred in 69% of patients. Struvite renal calculi continue to be a significant problem in the spinal cord injury population.

Adolescent↗
PubMed2000

The current therapy of urinary calculi in Thailand.

The paper analyses the impact of modern therapy of urinary calculi in Thailand since the introduction of ESWL and endourology (PCNL and URS) in 1988. Up to then, conservative and open surgical measures had been the standard procedures. The study covers 12 medical centres in the north, northeast, south and central parts of the country between 1988 and 1997. Approximately 40 ESWL machines have been in use. ESWL was used in 66.1 per cent and 20.8 per cent of patients with renal and ureteric calculi respectively. Only 1.1 per cent of the patients had PCNL. URS was used in 20.8 per cent of patients with ureteric calculi. Open operations were required in 32.6 per cent and 53.6 per cent of patients with renal and ureteric calculi respectively. Nephrectomy was required in 4.8 per cent--16.0 per cent of patients with renal calculi. Certain considerations have been put forward to appraise the situation concerning urinary stone therapy in Thailand.

Adult↗