J. Graff

Long-Term Followup in 1,003 Extracorporeal Shock Wave Lithotripsy Patients

We evaluated 1,003 patients treated with extracorporeal shock wave lithotripsy after a mean followup of 19.1 months (range 12 to 26 months). Followup excretory urograms were normal in 97 per cent of the patients. Two-thirds of the patients reported further discharge of residual fragments, mainly during the first 3 months. Rehospitalization was necessary in 57 patients. Over-all, the rate free of stones after followup was 72.2 per cent and it was not different for primary and recurrent stone patients. Rates free of stones were influenced mainly by the primary stone location and the number of stones in a renal unit. Patients with lower caliceal stones had a rate without calculi of only 57.8 per cent. Almost identical results were obtained for stones other than in the lower calix, when fragments were found in the lower calix at the time the patient was discharged from the hospital. The pre-treatment stone volume, as determined by measuring the stone area in square millimeters, did not influence the final rates free of stones for calculi up to 400 mm.2, that is 2.4 cm. of a sphere. Only calculi larger than 400 mm.2 showed an inverse relationship to the final rate free of stones. Multiple stones yielded a success rate of 64 per cent, with 90 per cent of the patients having regrowth of residual fragments. Serious complications during followup were not encountered.

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.

Extracorporeal Shock Wave Lithotripsy for Ureteral Stones: A Retrospective Analysis of 417 Cases

We treated 417 patients with upper ureteral stones with extracorporeal shock wave lithotripsy. All patients with obstructing stones underwent retrograde manipulation, which was successful in 57 per cent. Management of obstructing stones in situ (215 patients) with and without decompression of the collecting system required additional treatments in 13 per cent and ancillary procedures in 25 per cent. Nonocclusive ureteral stones were not manipulated. Treatment of these stones in situ slightly increased the need for postoperative ancillary procedures, compared to successful repositioning into the kidney (5.9 versus 3 per cent). Secondary treatments, however, were necessary as often as with occlusive stones. The main reason for failure of extracorporeal shock wave lithotripsy was the lack of fluid around an impacted stone. An energy absorptive effect of muscle tissue for stones projecting on the psoas muscle could not be demonstrated. The best and most consistent results were obtained when the stone was manipulated successfully into the renal collecting system.

Critical Evaluation of Treatment of Staghorn Calculi by Percutaneous Nephrolithotomy and Extracorporeal Shock Wave Lithotripsy

The combined use of percutaneous nephrolithotomy and extracorporeal shock wave lithotripsy in patients with staghorn calculi has become an established treatment regimen. We evaluated the results of 90 staghorn calculi-bearing kidneys treated with such combination therapy after a mean follow-up of approximately 2 years. A total of 69 kidneys (76.7 per cent) became free of stones at some point after treatment. However, due to stone recurrence this number decreased to 55 kidneys (61.1 per cent) at the end of follow-up. Patients who had undergone a previous open operation on the stone-bearing kidney showed less favorable results than the over-all group. When our results were compared to reported data on open surgery or percutaneous nephrolithotomy alone even better results may have been obtained by such treatment modalities. However, our data indicate that percutaneous stone debulking combined with further destruction of residual stone fragments by shock wave lithotripsy certainly is less invasive than an open operation and provides an alternative to percutaneous treatment alone, which can yield comparable results.

Effect of High-Energy Shock Waves on Bony Tissue

The indication for extracorporeal shock-wave lithotripsy (ESWL) in the treatment of lumbar and distal ureteral stones is well established. Ureteral calculi projecting onto the bony structures of the pelvis are not amenable to ESWL. Treatment options would include shock-wave treatment with the patient in a prone position where shock waves would pass through intestinal structures, or in a supine position where shock waves would traverse the pelvic bones. In order to investigate the effect of high-energy shock waves on bony tissue, an experimental study was undertaken using 26 female rabbits weighing 2.3–4.4 kg. Under intravenous anesthesia, the left anterior iliac spine and the left distal femur were each exposed to 1500 shocks. A generator voltage of 20 kV (1000 bars) and 25 kV (1300 bars) was used in each of two groups of 12 rabbits. Treatments were performed using the Dornier HM3 lithotripter. Four animals from each group were sacrificed after 2, 14, and 21 days following shock wave. A thorough necropsy examination was performed and all exposed tissues were examined histologically.

New Generator for Low Pressure Lithotripsy with the Dornier HM3: Preliminary Experience of 2 Centers

The technical innovation of a low pressure generator with a standard ellipsoid installed into the Dornier HM3 lithotriptor leads to a decrease in pressure at the second focus by 30 per cent. The preliminary experience with 273 patients treated at 2 centers is presented. The success rate in terms of stone disintegration was similar compared to the old generator (96 versus 97 per cent). However, the rate of secondary treatments increased from 8 to 15.5 per cent, respectively. Owing to the lower peak pressures at the second focus, an additional 700 impulses per session were necessary. The method of anesthesia was changed to a combination of an anxiolytic and analgesic drug in the majority of the patients. Treatment was judged as free of pain or with easily tolerable pain in 93 and 88 per cent of the patients, respectively.

Erfahrungen mit der ESWL bei 417 hohen Harnleitersteinen

In einer retrospektiven Analyse haben wir die Behandlungsergebnisse von 417 Patienten mit Harnleitersteinen ausgewertet, welche von Juli 1984 bis Januar 1986 an unserer Klinik behandelt wurden (17,9% des Gesamtkollektivs der ESWL-Patienten). Die Steinlokalisationen waren wie folgt verteilt: 44% subinfundibular, 35% hochlumbal und 18% mittelumbal. Bei 20% der Patienten lag ein zusatzliches Nierenbecken- und/oder Kelchkonkrement vor. Bei jedem okkludierenden Harnleiterstein wurde primar die Reposition mittels eines Ureterenkatheters versucht. Wenn die Reposition mislang, erfolgte eine Behandlung in situ oder die Einlage einer perkutanen Nephrostomie (Indikationen: Sepsis, deutlicher Kreatininanstieg, therapierefraktare Koliken). Somit wurden bei 87,5% der Patienten praoperativ adjuvante Masnahmen durchgefuhrt. Der Erfolg der Reposition war unabhangig vom Steinquerdurchmesser und von der Liegezeit des Konkrementes.

Influence of Papaverine on Rat Bladder Contractions in vivo

In an acute rat model (in vivo) spontaneous rhythmic bladder contractions were induced by ligation of the urethra. In addition single bladder contractions were recorded during neurostimulation of the pelvic nerve. Spontaneous and electrically induced bladder contractions were sensitive to papaverine and isoprenaline in vivo. The basal bladder pressure and bladder contraction parameters were reduced more potently by isoprenaline. Blood pressure decreased significantly after isoprenaline injection (0.5-50 micrograms/kg = 4.73 x 10(-6)-4.73 x 10(-4) mol/l) and high concentration of papaverine (5 mg/kg = 2.95 x 10(-2) mol/l). Compared to isoprenaline papaverine was less toxic. These results are different to previous in vitro investigations in rat bladder strips. In vivo papaverine seems to be less effective on nerve-mediated bladder contractions and decreases bladder pressure. Our results indicate that beta-adrenergic receptors play a potent role in the inhibition of spontaneous and pelvic nerve-induced bladder contraction.

Four Years of Experience with Ureteroscopy: Technique and Results in More Than 500 Cases

Since the introduction of ureteroscopy in July, 1984, more than 530 procedures have been performed at our department for ureteral stones and various ureteral pathologies.

Technical Modifications of the Dornier HM3: Preliminary Results from a Single Center

Since October, 1986, three technical modifications have been introduced to the Dornier HM3 lithotripter: 1) The low-pressure generator works with reduced pressures in the second focus. At a generator voltage of 18 kV, a focus pressure of 600 bars is generated, compared to the old standard generator with 900 bars. This decreased focal pressure reduces the pain perception of the patient while maintaining an equally-effective stone disintegration. 2) The theoretical background for the introduction of a modified semiellipsoid reflector was to modify the shock-wave generation and propagation unit in such a way that most of the painful shock-wave elements would be eliminated. The diameter of the semi-ellipsoid was increased to 17.2 cm (standard HM3, 15.6 cm) and the geometric dimensions changed. These alterations lead to a more accurate focussing with reduction of the focal area which increased the energy in the second focus by 10–20% while using the same generator voltage. Because of the increased diameter, the area of shock-wave entry on the skin was diminished. This results in a considerably reduced pain perception during shock-wave release. 3) The twin-pulse technique represents a modification of the triggering unit. Synchronized with the R-wave of the ECG, two impulses are released at a constant interval of 70 msec. In order to avoid interference with atrial or ventricular conduction, the first impulse is released 30–40 msec after recognition of the ‘R’ wave.