Evaluation of the upper urinary tract using transureteric ultrasound--a review of the technique and typical imaging appearances.

Ureteric strictures and pelviureteric junction obstruction often present a diagnostic conundrum to radiologists, particularly after the first-line investigations have failed to provide a definitive answer. Transureteric ultrasonography (TUU) is a relatively novel technique performed by the radiologist, which uses a miniature endoluminal ultrasound probe to interrogate the ureteric anatomy and peri-ureteric soft tissues. In this review, we discuss how TUU is performed, and the normal imaging appearances of the ureter and surrounding anatomical structures. We also focus on the various pathological processes that can be accurately evaluated or diagnosed using TUU including lymphadenopathy, calculi, ureteric neoplasms, ureteritis, crossing vessels and aneurysms. As TUU is not well established in UK practice as yet, we suggest possible indications for its use in the diagnostic work-up of urological patients and future applications.

The issue of prophylactic antibiotics prior to flexible cystoscopy.

OBJECTIVE: The aim of this study was to determine whether single-dose parenteral antibacterial therapy significantly alters the rate of infection in patients undergoing flexible cystourethroscopy. PATIENTS AND METHODS: 162 patients were studied prospectively having either received parenteral antibacterial chemoprophylaxis prior to flexible cystourethroscopy or not. Pre- and postprocedure mid stream samples of urine (MSSU) were obtained to objectively evaluate the presence of infection. RESULTS: Gentamicin prophylaxis reduced the rate of post-cystoscopy-positive MSSUs from 21 to 5%. CONCLUSION: The surprisingly high rate of infection after flexible cystoscopy was significantly reduced by a single dose of gentamicin.

The effects of pH changes on human and ferret detrusor muscle function.

1. The effects of altering extracellular pH on the electrically evoked contractions of ferret and human bladder (detrusor) smooth muscle have been investigated. pH was varied by changing superfusate PCO2 or NaHCO3 concentration. Acidosis increased force when superfusate PCO2 was raised but decreased force when the NaHCO3 concentration was reduced. 2. Intracellular pH (pHi) in isolated ferret detrusor cells was measured separately by epifluorescence microscopy. Extracellular pH changes caused by altering superfusate PCO2 were accompanied by similar changes of pHi, whereas variation of the NaHCO3 concentration had smaller effects on pHi. 3. It was proposed that intracellular acidosis increased contraction but extracellular acidosis depressed contraction. 4. Other interventions, such as addition and removal of NH4Cl, Cl- replacement, and NaHCO3 replacement with HEPES, changed pHi and had predictable effects on force. It was possible to describe unique relationships between tension and either intracellular or extracellular pH regardless of the means whereby pH changes were brought about. 5. Resting tension was reduced whether brought about by either intracellular or extracellular acidosis. K+ contractures were similarly affected by acidosis. Ferret preparations showed low levels of spontaneous activity, which was reduced by acidosis and enhanced by alkalosis.

Does extracorporeal shockwave lithotripsy cause hypertension?

Several series have suggested that the incidence of hypertension following extracorporeal shockwave lithotripsy (ESWL) may be as high as 8%. In this study, changes in blood pressure and the incidence of hypertension have been observed in 733 patients 12 to 44 months after renal ESWL on the Dornier HM3. The incidence of hypertension following ESWL was 8.1%. In patients with a pre-ESWL diastolic pressure less than 90 mmHg, the incidence of those with a diastolic greater than or equal to 100 mm Hg post-operatively was significantly greater than that predicted by historical data. There was no overall change in the mean blood pressure of the group. The hypertensive risk of ESWL remains unclear. However, blood pressure surveillance should be performed following ESWL and a prospective study is required.

Is extracorporeal shock wave lithotripsy safe in patients with calcific arterial disease?

In an experimental model using calcified aortic and iliac vessels ex vivo it has been shown that extracorporeal shock wave lithotripsy (ESWL) does not produce radiologically detectable damage to the vessel wall using the treatment regimen required to destroy renal calculi in vivo. The wall of aneurysmal vessels differ in being both calcified and expanded, and whilst anecdotal evidence suggests that lithotripsy of these too may be safe, experimental evidence is not yet available.

Indomethacin as prophylaxis against ureteral colic following extracorporeal shock wave lithotripsy.

Ureteral colic occurs in 24 to 34 per cent of all patients following extracorporeal shock wave lithotripsy. Recent research has shown prostaglandin synthetase inhibitors to be effective in relieving the pain associated with ureteral colic. Our prospective, controlled, double-blind, randomized study was designed to test the efficacy of indomethacin in the prophylactic treatment of pain after extracorporeal shock wave lithotripsy. Patients undergoing extracorporeal shock wave lithotripsy were randomized into 2 groups. Group 1 received 100 mg. indomethacin suppositories twice daily and group 2 received placebo suppositories. After extracorporeal shock wave lithotripsy 2 analgesics were available to the patients: oral co-dydramol or intramuscular pethidine was offered in the normal manner by the nursing staff. The pre-extracorporeal shock wave lithotripsy x-ray was used to make a quantitative estimate of the total stone burden in each patient. The post-extracorporeal shock wave lithotripsy analgesic requirement was used to compare the 2 groups. Of 112 patients recruited to the study 55 received indomethacin and 57 received placebo. The request for analgesia in the 2 groups was not different (28 of 55 and 33 of 57, respectively). However, in the indomethacin group only 6 patients required pethidine (10 doses), compared to 18 (41 doses) in the placebo group. This difference is statistically significant (p less than 0.01). There was no difference between the 2 groups in the occurrence of ureteral steinstrasse. Indomethacin has been shown to be effective in the prophylactic treatment of ureteral colic after lithotripsy.

Clinical comparison of extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy in treating renal calculi.

STUDY OBJECTIVE: To compare extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy for efficacy in treating renal calculi. DESIGN: Non-randomised multicentre cohort study with 3 month follow up and 13 month data collection period. SETTING: Lithotripter centre in London, tertiary referral hospital, and urological clinics in several secondary and tertiary care centres. PATIENTS: 933 of 1001 patients treated by lithotripsy at the lithotripter centre were compared with 195 treated by nephrolithotomy. Missing patients were due to incomplete collection of data. Age and sex distributions and characteristics of the stones were similar in the two treatment groups. Two patients died in the lithotripsy group. Three month follow up was achieved in about 84% of both groups (783/933 for lithotripsy; 163/195 for nephrolithotomy). INTERVENTIONS: The nephrolithotomy group had surgical nephrolithotomy alone. In the lithotripsy group 83% (774/933) had lithotripsy alone, 11% (103/933) had combined lithotripsy and nephrolithotomy, and 6% (56/933) had lithotripsy plus ureteroscopy. Single and combined lithotripter treatments were analysed as one group and compared with nephrolithotomy. END POINT: Presence of stones three months after treatment. MEASUREMENTS AND MAIN RESULTS: Presence of residual stones was assessed by plain radiography, ultrasonography, or intravenous urography. After adjustment for age and size and position of stone for patients with single stones the likelihood of being free of stones three months after treatment was significantly greater in the nephrolithotomy group than the lithotripsy group (odds ratio 6.6; 95% confidence interval 3.0 to 14.6) and the response was particularly pronounced with staghorn calculi (62% (8/13) v 15% (141/96) patients free of stones after nephrolithotomy and lithotripsy, respectively). OTHER FINDINGS: 19%(146/775) of patients who had had lithotripsy had to be readmitted within three months after treatment compared with 14%(23/162) who had nephrolithotomy; and 64%(94/146) of readmissions after lithotripsy were for complications compared with 30%(7/23) of readmissions after nephrolithotomy. CONCLUSIONS: Nephrolithotomy may be preferable to lithotripsy for treating renal stones and it may not be wise to invest heavily in lithotripsy facilities.

The destruction of renal calculi by external shock-waves: practical operation and initial results with the Dornier lithotripter.

ESWL is now the treatment of choice for most renal calculi. Large stones (20 mm) and staghorn stones may require preliminary debulking before lithotripsy and stones in the lower part of the ureter require pushing back into the renal pelvis before treatment. Compared with open surgery and percutaneous nephrolithotomy the procedure is less traumatic for the patient and may result in a shorter hospital stay and a faster return to normal life for the patient. It has been estimated that in 10 to 20 years' time around 70% of patients with urinary stone disease will be treated by ESWL.

Report on the first 1000 patients treated at St Thomas' Hospital by extracorporeal shockwave lithotripsy.

Since March 1985, over 1000 patients have been treated on the lithotripter at St Thomas' Hospital. Since it is the only machine in the country offering treatment to National Health Service patients at no cost to the referring Health Authority, there has been a heavy demand for treatment and 97% of referrals have been accepted. Analysis of the first 1000 patients shows extracorporeal shockwave lithotripsy (ESWL) to be a safe procedure with a low morbidity rate and no mortality. The number of patients who were stone-free 3 months after treatment was low (44.1%) compared with the numbers reported in other series. The most likely reasons for this are the poor follow-up rate (48.9%), the stringent criteria for the diagnosis of "stone-free" and a possible skewed referral and follow-up pattern.

A new in vitro microsuperfusion technique for investigation of human detrusor muscle.

There is a paucity of information regarding the behaviour of human detrusor muscle in vitro. This is mainly due to the dependence of muscle bath techniques on large strips of material, which can be obtained only at open operations and which may not be viable because of limited diffusion of oxygen and metabolites through the tissue. We report a new technique for the in vitro study of muscle obtained during endoscopic procedures by cup biopsy. The results obtained from normal muscle show that this technique gives consistent and reproducible results.