Cost-effectiveness of extracorporeal shock-wave lithotripsy

A study was done comparing the charges and outcomes for extracorporeal shock-wave lithotripsy (ESWL) with those for percutaneous nephrostolithotomy (PCN), which was the treatment of choice at our hospital for stones of the upper urinary tract when ESWL was introduced. Using a retrospective cohort design, patients were matched for age, sex, physical status index (American Society of Anesthesiologists), stone size, and urinary tract obstruction. Twenty-nine pairs of PCN and ESWL patients with complete data were matched. The groups were not significantly different in the matching parameters. Seventy-two per cent of patients in each group (21/29) were stone-free after the initial hospitalization. PCN patients required more auxiliary procedures per patient than did the ESWL patients; in addition, 5 (17%) of the PCN patients had perforation of the renal pelvis and 5 (17%) required transfusions. On discharge, 48 per cent (14/29) of the PCN patients had nephrostomies compared with none of the ESWL patients. The ESWL group had a shorter mean length of stay (2.9 vs 8.7 days, p less than 0.0005) and lower charges in all categories. Total charges were significantly less for ESWL ($9,290 vs $11,796 for PCN, p less than 0.005) as were physicians' fees ($3,391 vs $5,607, p less than 0.0005), room and board charges ($825 vs $2,164, p less than 0.0005), and operating room fees ($313 vs $1,452, p less than 0.0005). We conclude that ESWL is a cost-effective means for treating stones of the kidney and upper urinary tract.     

The effect of different calcium antagonists and a calcium agonist on the metabolism of propranolol by isolated rat hepatocytes

Summary— The influence of the dihydropyridine calcium entry blockers nicardipine, amlodipine, nifedipine, isradipine and of the dihydropyridine calcium entry promotor BAY K 8644 on the disappearance rate of propranolol by isolated rat hepatocytes was compared to the effect of diltiazem and verapamil, two non-dihydropyridine calcium channel blockers and known inhibitors of hepatic cytochrome P450 mixed function oxidases. All compounds dose-dependently inhibited the disappearance rate of propranolol. Nicardipine and isradipine were more potent in inhibiting the disappearance rate of propranolol than the other dihydropyridines and than diltiazem and verapamil. The inhibitory effect of nicardipine on the disappearance rate of propranolol was not stereoselective and was not influenced by age.     

Bone scintigraphy in chondroblastoma

Scintigraphy in 3 patients with chondroblastoma showed that the tumors were hyperemic and avidly accumulated the radionuclide. These changes were also present in adjacent normal bone, but to a lesser degree. This suggest that radionuclide uptake in chondroblastoma is a function of the blood supply to the tumor rather than primary matrix extraction.     

Extracorporeal shock-wave lithotripsy for children

We report the cases of 17 children between the ages of 3 and 17 years who underwent 19 treatments using extracorporeal shock-wave lithotripsy. Stone size averaged 14.9 mm, with a range of 3 to 25 mm. The number of shock waves delivered averaged 1720, with a range of 600 to 2000. Treatment time averaged 36 minutes, with a range of 15 to 55 minutes. The average length of hospital stay was 2.2 days. In nine of the 19 treatments the kidneys were rendered free of stones. There were no complications.     

Congenital hepatic artery aneurysm simulating pancreatic carcinoma

The authors report a case of a hepatic artery aneurysm that simulated a mass in the head of the pancreas. The correct diagnosis was made preoperatively based on several findings: curvilinear calcification within the mass on CT, a well-defined cystic collection on ultrasound, absence of biliary duct dilatation or jaundice, and presence of other aneurysms.     

3D polymer scaffolds for tissue engineering

This review discusses some of the most common polymer scaffold fabrication techniques used for tissue engineering applications. Although the field of scaffold fabrication is now well established and advancing at a fast rate, more progress remains to be made, especially in engineering small diameter blood vessels and providing scaffolds that can support deep tissue structures. With this in mind, we introduce two new lithographic methods that we expect to go some way to addressing this problem.