Interobserver variation in the interpretation of abdominal radiographs

A total of 140 sets of abdominal radiographs were reviewed independently by four qualified diagnostic radiologists. The degree of interobserver agreement was determined by calculating kappa values for 19 commonly used radiographic signs and diagnoses. There was fair to excellent interobserver agreement for 11 signs and diagnoses and poor agreement for the remaining eight. The signs and diagnoses for which agreement is poor cannot be considered reliable and include particularly large bowel obstruction and nonspecific gas pattern.     

Effect of intersection spacing on MR image contrast and study time

The effects of section separation on image contrast and calculated T1 relaxation times were investigated in healthy volunteers and a phantom using an early commercial version magnetic resonance imaging system. The effects are explained qualitatively on the basis of side lobes of excitation occurring outside the selected section resulting in reduction of the time permitted for T1 relaxation. The options for dealing with imperfect section selection, including separation of the sections (i.e., leaving gaps) and nonsequential excitation, are illustrated and the trade-offs involved in each explained.     

Glutathione-S-epoxide transferase in human hair follicles

A fluorometric assay for determination of glutathione-S-epoxide transferase (GSH-T) activity in freshly isolated human hair follicles or cultured cells is described. With this assay, basal levels of the enzyme in hair follicles have been compared between smokers and non-smokers. No significant difference between both groups could be detected. GSH-T was not elevated after treatment of cultured hair follicle keratinocytes with benz[a]anthracene or clotrimazole. The same result was obtained with cultured skin fibroblasts from Ah-responsive and Ah-non-responsive mice. The possible significance of basal GSH-T levels for assessment of the risk of individuals for the carcinogenic action of polycyclic aromatic hydrocarbons is discussed.     

Pharmacokinetics and pharmacodynamics of lobaplatin (D-19466) in patients with advanced solid tumors, including patients with impaired renal of liver function.

The purpose of this study was to determine the influence of impaired renal and liver function on the pharmacokinetics and pharmacodynamics of lobaplatin in cancer patients. A total of 25 patients with advanced solid tumors not amenable for standard treatment entered the study. Patients had normal organ function or an impaired liver or renal function (two levels). The starting dose of lobaplatin was 50 mg/m2 i.v. given every 3 weeks. The blood and urine of all patients were sampled for the determination of (ultrafilterable) platinum, intact lobaplatin, creatinine, and blood cell counts. No objective responses were recorded. Five patients experienced no change and received 4-10 cycles (median, 6 cycles) of lobaplatin. The extent and duration of hematological toxicity were worse in patients with impaired renal function. Thrombocytopenia was most prominent; grade 4 toxicity was observed in 15 patients in the first two cycles of treatment. The concentration-time curves of ultrafilterable platinum and intact lobaplatin revealed almost identical patterns. The elimination of ultrafilterable platinum [final half-life (t1/2 final) = 131+/-15 min; clearance (Cl) = 125+/-14 ml/min/1.73 m2] was much faster than that of total platinum (t1/2 final = 6.8+/-4.3 days, CI = 34+/-11 ml/min/1.73 m2). No pharmacokinetic differences were observed between patients with normal organ function and those with an impaired liver function within the investigated range. An impaired renal function resulted in an increase of the t1/2 final due to a decrease of the total body Cl that resulted in a higher exposure of the body to the drug. The calculated creatinine Cl was linearly correlated with the total body clearance of ultrafilterable platinum (r = 0.91), which resulted in the dosage formula D = AUCinfinity (1.1 Cl(CrU) + 16), in which D represents dose, AUC represents area concentration-time curve, and Cl(CrU) represents creatinine Cl. The thrombocyte surviving fraction correlated well with the AUC value of ultrafilterable platinum (r = 0.72). It can be concluded that the hematological toxicity and the pharmacokinetics of lobaplatin are strongly affected by renal function. The total body Cl of ultrafilterable platinum correlated well with the creatinine Cl and the thrombocyte surviving fraction. In patients with renal function, represented by a creatinine clearance > or =30 ml/min/1.73 m2, the derived dosage formula will enable us to calculate the dose that is expected to lead to an acceptable extent of thrombocytopenia in a patient with a given renal function. Prospective studies with larger groups of patients are needed to prove the value of this dosage formula.     

Perforation of the inferior vena cava with aortic and vertebral penetration by a suprarenal Greenfield filter

Various complications have been reported after insertion of the Greenfield filter. This report describes an unusual complication after suprarenal placement of this filter: spreading of the filter struts, with perforation of the inferior vena cava, and penetration of the aorta and a vertebral body, followed by fracture of one of the struts.     

Pharmacokinetic comparison of cisplatin in solution with common lyophilized cisplatinum (Platinol)

Total platinum kinetics were studied after the administration of two formulation products of cisplatin: the lyophilized form and a ready-to-use solution. Twelve patients received both preparations during two successive cycles in a randomized crossover study. Platinum concentrations in plasma and urine were measured by atomic absorption spectrometry. Data were analyzed by means of a mixed-effect analysis of variance. Areas under the concentration-time curves up to 96 h were increased (p = 0.026) and slopes of the elimination phase were decreased (p = 0.035) during cycle 2 when compared with cycle 1. However, no difference in these two parameters was observed when comparing the two formulations. Three-day urinary platinum excretion was not related to either the treatment cycle or the formulation used. Because of its convenience of use and reduced risk of aerosolization, the ready-to-use formulation seems preferable.     

High-resolution MR imaging with local coils

We propose the following rules to govern the choice of local coils by the practicing radiologist: 1. Smaller coils permit smaller FOVs and better resolution. The coil should be as small as possible. 2. Match the ROS of the coil to the FOV, which will be determined by the anatomic region of interest. 3. For the case of a choice between surface coils or between a surface and a whole- or partial-volume coil, the anatomic region should lie on the high side of the crossover point. For the case of a choice among whole-volume coils, the smallest coil that surrounds the region of interest should be chosen. 4. Considerations in regard to the anatomic shape or the need to vary the position of the structure may alter the choice of coil from that obtained by S/N considerations alone.