Parameters influencing piezoelectric shock wave lithotripsy of biliary calculi.

A total of 225 human gallbladder stones were divided into sets of two, three, or four identical calculi (with maximum diameters of 6-26 mm) and submitted to piezoelectric shock wave lithotripsy in vitro in order to investigate the influence of the following parameters on stone disintegration: shock wave intensity, pulse frequency, and various physicochemical parameters such as the volume and viscosity of the fluid surrounding the stone, the hardness of the calculus, and its chemical composition. The fragmentation efficacy increased with enhanced shock wave energy (P less than 0.01). If the volume of the fluid (30 mL) surrounding the calculus was small, the disintegration end-point (defined by maximum fragment diameters less than or equal to 4 mm) was achieved after a lower number of pulses (median: 250 pulses) than in the case of a large fluid volume (80 mL) (500 pulses; P less than 0.01). On the other hand, however, factors such as the shock wave pulse rate (0.9 Hz vs 1.6 Hz), variations in viscosity of a water-jelly mixture surrounding the stone, the chemical composition of the stones as determined by X-ray diffractometry, and stone hardness were found to have no significant influence on the fragmentation efficacy.

Significance of computed tomography for shock-wave therapy of radiolucent gallbladder stones.

One hundred eleven symptomatic patients (91 women, 20 men) with solitary "radiolucent" stones (proved by a plain radiograph) underwent examination with computed tomography for stone analysis before extracorporeal shock-wave lithotripsy with a second-generation piezoelectric lithoptripter. The aim of the study was to assess the importance of computed tomography as a diagnostic pretreatment procedure compared with the plain abdominal radiograph: computed tomography density values greater than 50 Hounsfield units (HU) were found in 64 of 111 patients with radiolucent stones (58%). Of these 64, 50 patients even had values greater than 90 HU (50/111;45%). The majority of the stones with density values greater than 50 HU had a hyperdense rim (43 of 64) with a mean maximum attenuation of 134 +/- 68 HU. A significantly higher degree of stone disintegration was achieved with stones of group A (less than or equal to 50 HU) than with those in group B (greater than 50 HU and less than or equal to 90 HU) and group C (greater than 90 HU) with respect to the mean maximum fragment size after the first (P less than 0.001) and last (P less than 0.01) lithotripsy and with respect to the total number of shock waves applied (P less than 0.001) and the number of treatments (P less than 0.001). No difference was observed between groups B and C. After all follow-up periods, the rate of complete stone disappearance was higher in group A than in group B (NS for 1, 2, and 4 months of follow-up; P less than 0.01 for month 8; P less than 0.05 for month 12) and group C (P less than 0.05 for 1, 2, and 4 months of follow-up; P less than 0.001 for months 8 and 12). The authors conclude that computed tomographic analysis of gallstones before lithotripsy is more sensitive in detecting nonradiolucent stones than in the plain radiograph. Computed tomographic stone analysis seems to provide a better selection of patients suitable for biliary lithotripsy and could become a standard diagnostic pretreatment procedure to improve stone disintegration and complete stone disappearance after shock-wave lithotripsy and adjuvant chemolitholysis.

[Imaging procedures prior to the extracorporeal shockwave lithotripsy of gallstones]. / Bildgebende Verfahren vor extrakorporaler Stosswellenlithotripsie von Gallenblasensteinen.

In order to determine whether cholecystography and computed tomography (CT) are capable of better gallstone characterization than conventional radiography alone, 91 patients (76 females, 15 males; mean age 47 +/- 12 years) with symptomatic single gallstones were studied prospectively prior to extracorporeal shock-wave lithotripsy with concomitant oral stone dissolution therapy. In addition, the value of oral cholecystography in demonstrating patency of the cystic duct was compared with ultrasound assessment of gallbladder function. Despite "negative" plain gallbladder radiographs in all patients, oral cholecystography showed significant stone calcification in 8 of the 91 patients and CT showed stone calcifications in 52 of the 91 patients. In 12 patients the maximum stone density was between 50 and 90 Hounsfield units, and in 40 patients it was more than 90 Hounsfield units. CT revealed ring-like calcification in the majority (79%) of these stones. Oral cholecystography showed satisfactory concentration of contrast medium in all patients, while ultrasonography of the gallbladder following a chemically defined test meal demonstrated contractility of more than 50% of initial volume in 69 patients and of less than 30% in 9 patients. Although oral cholecystography is a simple, readily available complication-free method, ultrasound assessment of gallbladder contraction is better for selecting patients for extracorporeal shock-wave lithotripsy. CT allows significantly better characterization of gallstones than oral cholecystography and conventional plain gallbladder radiography.

[Experimental detection of hemorrhage in the circulation area of the superior mesenteric artery by intra-arterial nuclide angiography]. / Experimenteller Nachweis von Blutungen im Versorgungsgebiet der A. mesenterica superior durch intraarterielle Nuklidangiographie.

A new experimentally proven method for diagnosis and localisation of acute bleeding in the flow area of the arteria mesenterica superior is reported. By selective intra-arterial nuclide injection microhemorrhage below the proof limit of angiography can be registered and relatively exact localized by additional geometric procedure. Using this method, the exact location of angiographic, negative bleedings could be determined in experimentally produced bleedings in the jejunoileal transit and in the distal ileum. We explain the experimental arrangement and the results. The diagnostic value of the examination is discussed.

[Isolated pleural recurrence of Hodgkin's disease]. / Isoliertes pleurales Rezidiv eines Morbus Hodgkin.

Relapses of Hodgkin's disease are predominantly nodal or systemic. An extranodal manifestation is a rare exception. We report on a patient who developed an isolated pleural relapse at the margin of the irradiation field after successful radiotherapy of a Hodgkin's disease stage I.

[Intramural pseudodiverticulosis of the esophagus]. / Die intramurale Pseudodivertikulose des Osophagus.

Esophageal intramural pseudodiverticulosis is a rare condition of yet unknown etiology. Histologic findings of pseudodiverticulosis are characterized by dilated submucosal mucous glands in the esophagus wall. The clinical features including slowly progressive dysphagia mimic those of esophageal carcinoma. The diagnosis is established by radiologic examination, revealing numerous tiny outpouchings of the esophagus wall filled with contrast material. Endoscopic biopsy of the frequently associated stenosis of the upper esophagus is mandatory. Computer tomography shows localized thickening of the esophagus wall. Manometry reveals motoric dysfunction. Etiology and therapeutic management are discussed.

[Chemotherapy of metastatic gastric cancer--x-ray follow-up]. / Chemotherapie bei metastasierendem Magenkarzinom--eine röntgenologische Verlaufsbeobachtung.

In most cases of metastatic gastric cancer, treatment with cytostatic drugs seems to be justified. Responsiveness to chemotherapy, according to the MAF-schedule (Methotrexate, Adriamycin, 5-Fluorouracil) was reported to be successful in 50% of this cancer type.