Pulmonary embolism and lung scanning: cost-effectiveness and benefit:risk

The cost-effectiveness of pulmonary imaging (lung scan) on the management of 2,023 patients was studied. Prior and postscan probabilities of pulmonary embolism (PE) were obtained from referring physicians. After the scan, anticoagulant therapy (ACT) was appropriately changed in 20% of the patients and confirmed in 67%. The incremental cost of scanning was $124 per patient when the prior probability was 0.01-9.99%, dropping to $38 when the probability was 10-25%. Hospitalization and ACT cost was reduced when the prior probability was 25.01-99.99%. The greatest benefit in lives saved was when the prior probability was 25-74.99%; 1.5% of this probability group would survive as a result of the change in management attributable to the scan, at a cost of $117 per life saved. The benefit:risk ratio, as measured by lives saved compared to estimates of lives lost due to radiation exposure, was of the order of 6,000:1.     

Percutaneous Biliary Interventions: Inside and Outside the Box: Gallbladder: Role of Interventional Radiology

Percutaneous cholecystostomy is an established procedure for the management of patients with acute cholecystitis and with significant medical comorbidities that would make laparoscopic cholecystectomy excessively risky. In this review, we will explore the role of percutaneous cholecystostomy in the management of acute cholecystitis as well as other applications in the management of biliary pathology. The indications, grading, technical considerations, and postprocedure management in the setting of acute cholecystitis are discussed. In addition, we will discuss the potential role of percutaneous cholecystostomy in the management of gallstones and biliary strictures, in establishing internal biliary drainage, and in a joint setting with other clinicians such as gastroenterologists in the management of complex biliary pathology.     

Comparison of ERCP and MRCP: invasiveness and cost

The purpose of this study was to compare ERCP and MRCP in terms of invasiveness and cost. A questionnaire regarding patient satisfaction was distributed to 23 ERCP patients and 63 MRCP patients. The practical cost of each examination and total yearly cost for 2002, including medication costs for post-ERCP pancreatitis, were calculated. On a trial basis, the total yearly cost for 2002 was also calculated as a percentage of the cost in 1996. Results of the questionnaire showed that patients tended to favor MRCP over ERCP. In our hospital, the practical costs of MRCP and ERCP were 2063 points and 3964 points, respectively. Medication costs for pancreatitis corresponded to about 3% of the total yearly cost for ERCP. The total yearly costs for both examinations and the medication costs for pancreatitis were about 1,360,000 points. The result of trial calculation with the examination percentage of 1996 was about 1,950,000 points. The results of our study demonstrated that MRCP is a noninvasive examination for patients and that its popularization contributed to a reduction in medical costs. For further popularization of equipment and advanced imaging methods, careful assessment of examination costs is important.     

Sorption and desorption of Co(II) on alumina:: mechanisms and effect of humic substances

The effects of pH, ionic strength and humic substances on the sorption and desorption of Co(II) on alumina and silica were, respectively investigated by using radiotracer ⁶⁰Co. The distribution coefficients, the breakthrough curves and the displacement curves were experimentally determined in the batch and the column experiments. The pH and the humic substances influenced the sorption of Co(II) on alumina greatly as compared with the sorption of Co(II) on silica. It was found that the sorption characteristics of Co(II) onto alumina and silica are distinctly different, that the strong chemical bonds are formed between the bare alumina surface and Co(II) and between the coated alumina surface and Co(II), and that a transition from the adsorption to the surface-induced precipitation of Co(II) on the bare alumina surface takes place.     

Antihistamines and aircrew: usefulness of fexofenadine

INTRODUCTION: The aim of this study was to establish whether fexofenadine hydrochloride, an antihistamine, modulates daytime sleepiness or performance. METHODS: The effects of fexofenadine (120, 180, and 240 mg) on digit symbol substitution, tracking, and vigilance tasks, and on objective (multiple sleep latency test) and subjective sleepiness, were studied in six healthy volunteers (two males, four females, aged 20-34 [mean 26.5] yr) from 1 h pre-ingestion to 8 h post-ingestion. The study was placebo-controlled and double-blind with a six-way cross-over design. The centrally acting antihistamine, promethazine (10 mg), was used as an active control to confirm the sensitivity of the experimental procedures. RESULTS: There were no changes in performance or sleepiness with any dose of fexofenadine at any time, compared with placebo. Promethazine, compared with both placebo and fexofenadine, impaired performance on the digit symbol substitution task (2.5 h post-ingestion), vigilance task (2.5-5h post-ingestion) and tracking task (2.5-3.5 h post-ingestion), increased objective sleepiness (1.5-2.5 h post-ingestion) and subjective sleepiness (1.5-8h post-ingestion). CONCLUSION: Consideration may be given to the clinical use of currently licensed doses of fexofenadine (120-180 mg) by individuals involved in skilled activity. Fexofenadine may be potentially useful for aircrew.     

Verification of IMRT: Techniques and Problems

PURPOSE: IMRT (intensity-modulated radiotherapy) verification techniques are reviewed together with investigations demonstrating the intrinsic verification problems. MATERIAL AND METHODS: Different IMRT verification procedures for either class solutions or individual patients are demonstrated. Among the latter are techniques like fluence or three-dimensional (3-D) dose distribution verification within a transfer phantom. Different radiographic films and absolute dose probes are investigated for their suitability. Finally, Monte Carlo techniques (XVMC/VEF) are used for error detection and IMRT verification. RESULTS: During introduction of clinical IMRT for head and neck (H and N) tumors, we concurrently applied fluence, relative, and absolute dose measurement. While fluence and relative dose are in rather good agreement with calculations, absolute dose is always low when compared to the TPS (TMS 6.1A, Nucletron B.V.) by 5-7%. This deviation seems to depend not on the number of segments, but can strongly depend on MLC misalignment. Further investigations have revealed the importance of a detailed commissioning of the TPS down to the small-field range using diamond or diode probes and its detailed verification. In addition, simple tests have shown that dose calculation approximations in the IMRT option of TMS are one major source of the dose deviation. XVMC/VEF does not use such approximations. CONCLUSION: The procedure starts with a detailed TPS commissioning and verification process. Different verification methods are recommended during clinical IMRT implementation phase, in order to locate sources of error. Later on, a minimal program could consist of a fluence or relative dose verification procedure with few films and absolute dose measurement, followed by an intensive MLC quality assurance (QA). Inverse Monte Carlo systems, like IMCO(++)/IKO or Hyperion, seem to be able to reduce the effort.     

Analysis of doping: possibilities and limitations

The role of modern instrumental analysis in today doping control procedures is described. With reference to the analytical methods, to the requirements of the International Olympic Committee for laboratory accreditation and to the regulations for substantiating a positive result, we show how a laboratory for doping control is functioning. The limits of today analyses are shown, making it obvious that the analytical results from an accredited laboratory are not the weak point in doping control.     

Telemedicine: opinions of dermatovenerologist and patient

The article presents the results of the survey of the dermatovenereologists and patients to explore their attitude to the telemedicine consultations. It is found that most of the dermatovenereologists have the positive attitude towards telemedicine consultations. From the perspective of patients using telemedicine technology is likely to breach the protection of personal privacy.     

The lumbar facet joint: a review of current knowledge: Part II: diagnosis and management

This article is the second article in a two-part review on lumbar facet joint pathology. In this review, we discuss the current concepts and controversies regarding the proper diagnosis and management of patients presenting with presumed facet-mediated lower back pain. All efforts were made to include the most relevant literature from the fields of radiology, orthopaedics, physiatry, and pain management. Our focus in this article is on presenting the evidence supporting or refuting the most commonly employed injection-based therapies for facet-mediated lower back pain.     

Percutaneous Biliary Interventions: Inside and Outside the Box: Biliary Strictures: Etiologies and Medical Management

Biliary strictures have several etiologies that can broadly be classified into benign and malignant causes. The clinical presentation is variable with strictures identified incidentally on imaging or during the evaluation of routine laboratory abnormalities. Symptoms and cholangitis lead to imaging that can diagnose biliary strictures. The diagnosis and medical management of biliary strictures will be discussed in this article.