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This paper describes an experimental setup that combines friction measurements with in situ confocal Raman microscopy on a lubricating fluid film. The setup allows the determination of film thickness and shear-rate profiles, the position-dependent lubricant composition within the rubbing contact, as well as optical imaging of the contact and its surroundings. The tribological contact can be investigated at continuous rubbing conditions over a range of sliding speeds from 1×10-3 to 2 m/s. The setup’s capabilities are demonstrated for a soft poly(dimethylsiloxane) sphere pressed and rotated against a quartz flat. Friction forces are presented in the boundary, mixed, and elastohydrodynamic lubrication (EHL) regimes for both a hydrophilic and a hydrophobic flat surface. Optical images of the contact show that, for single-phase aqueous Newtonian lubricants in the EHL regime, starvation of the contact occurs above a critical value of the product of the entrainment speed and the lubricant viscosity. Starvation results in a lower film thickness and lower friction values than predicted by numerical calculations that do not take starvation into account. The capability to determine, using Raman spectroscopy, the composition of the lubricant within the contact is demonstrated for oil-in-water emulsions, stabilized by a nonionic surfactant (Tween 60). The oil concentration was found to depend on both the sliding speed and the position within the rubbing contact. For the investigated tribological conditions, the oil content within the contact was lower than that of the bulk emulsion. This is attributed to the fact that the aqueous matrix phase preferentially wets the hydrophilic quartz slide, which prevents oil droplets from entering the contact if the film thickness is of the order of the droplet size. The ability to determine friction forces, lubricant composition and film thickness, and shear-rate profiles will provide invaluable information in the pursuit of a better understanding of lubrication of soft and hard contacts by multiphase complex fluids. [ABSTRACT FROM AUTHOR]

We have developed and tested a multistep-index x-ray waveguide. The waveguide geometry allows for a controlled positioning of the waveguide gap down to the nanometer range. The waveguide consists of two closely spaced flat fused-silica substrates, coated with an aluminum layer. On top of the aluminum layer we deposited an optically transparent spacer layer. The aluminum layers are the mirrors of an optical interferometer, which is used to measure the separation and parallelism of the waveguide surfaces. The x rays are guided within the gap between the spacer layers. We have observed so-called cladding modes and demonstrate waveguiding in a multistep index structure having a gap width of 59 nm over a length of 5 mm. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Background: In ALK-positive advanced NSCLC, crizotinib has a high response rate and effectively increases quality of life and survival. CT measurement of the tumor may insufficiently reflect the actual tumor load changes during targeted therapy with crizotinib. We explored whether 18F-FDG PET measured metabolic changes are different from CT based changes and studied the impact of these changes on disease progression. Methods: 18F-FDG PET/CT was performed prior to and after 6 weeks of crizotinib treatment. Tumor response on CT was classified with RECIST 1.1, while 18F-FDG PET response was assessed according to the 1999 EORTC recommendations and PERCIST criteria. Agreement was assessed using McNemars test. During follow-up, patients received additional PET/CT during crizotinib treatment and second generation ALK inhibition. We assessed whether PET was able to detect progression earlier then CT. Results: In this exploratory study 15 patients were analyzed who were treated with crizotinib. There was a good agreement in the applicability of CT and 18F-FDG PET/CT using the EORTC recommendations. During first line crizotinib and subsequent second line ALK inhibitors, PET was able to detect progression earlier then CT in 10/22 (45%) events of progression and in the others disease progression was detected simultaneously. Conclusion: In advanced ALK positive NSCLC PET was able to detect progressive disease earlier than with CT in nearly half of the assessments while both imaging tests performed similar in the others. [ABSTRACT FROM AUTHOR]

Human epidermal growth factor receptor (HER)2 imaging with radiolabeled trastuzumab might support HER2-targeted therapy. It is, however, frequently questioned whether HER2 imaging is also possible during trastuzumab treatment as the receptor might be saturated. We studied the effect of trastuzumab treatment on 111In-trastuzumab uptake. Patients received trastuzumab weekly and paclitaxel once every 3 weeks, 111In-trastuzumab was injected on day 1 of cycle 1 and day 15 of cycle 4. Whole-body planar scintigraphy was acquired at different time points postinjection. Tumor uptake and organ distribution between the first and repeated scan series were calculated via residence times. Twenty-five tumor lesions in 12 patients were visualized on both scintigraphy series. Tumor uptake decreased (19.6%; p 5 .03). The residence times of normal organs remained similar except for the cardiac blood pool (+ 16.3%; p 5 .014). Trastuzumab treatment decreases tumor 111In-trastuzumab uptake around 20%. HER2 imaging is feasible during trastuzumab treatment. [ABSTRACT FROM AUTHOR]

To assess the diagnostic value of lung scintigraphy and helical computed tomography (hCT) in patients with suspected pulmonary embolism (PE), all English-language articles that described lung scintigraphy and hCT in patients with suspected PE were retrieved. Articles were assessed for strength of methodology, based on nine a priori-defined criteria. Parameters of diagnostic accuracy and results of management studies were calculated and evaluated. Lung scintigraphy is diagnostic in approximately 50% of patients with suspected PE. A normal perfusion scan has a chance of recurrent PE in two of 693 patients (0.3%; 95% CI: 0.2–0.4%: fatal in 0.15%). A high-probability lung scan is correlated with angiographically proven PE in 308 of 350 patients (88%; 95% CI: 84–91%). Pulmonary embolism was proven in 385 of 1529 patients (25%; 95% CI; 24–28%) with a nondiagnostic lung scan. Helical CT studies were compared with angiography and lung scintigraphy in 1171 patients, with a prevalence of PE of 39%. The sensitivity and specificity of hCT was 283/320 (88%; 95% CI: 83–91%) and 374/408 (92%; 95% CI:89–94%), respectively. Only one prospective management study using hCT was available. In patients in whom anticoagulants were withheld based on a normal hCT study, recurrent thromboembolic events occurred in six of 109 patients (5.5%; 95% CI: 2–12%), with one fatality (1%; 95% CI: 0.02–4.3%. Lung scintigraphy is evaluated extensively and yields a diagnostic result in 50% of patients. Helical CT has similar positive predictive value to a high-probability lung scan. However, the exact role of hCT in the management of patients with suspected PE needs to be determined in prospective studies. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 52-year-old female with low-grade follicilar non-Hodgkin lymphoma stage II, for which she undergo several cycles of chemotherapy. 18 F-fluorodeoxyglucose (18 -FDG) positron emission tomography (PET) showed uptake concentric around the transverse colon suspect for local recurrence of the disease. It mentions that the scan was repeated and showed active lymphadenopathy and multiple lesions in the peritoneum.

¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸FDG-PET) scintigraphy is a useful imaging technique in the evaluation of metastasised thyroid carcinoma. Administration of recombinant human thyrotropin (rhTSH, Thyrogen®) increases the diagnostic yield of this procedure. Here we present a 64-year-old male who was followed for Hürthle cell carcinoma of the thyroid with several intrapulmonary metastases. He developed sudden complaints of neck pain following rhTSH administration as part of the routine preparation for a diagnostic ¹⁸FDG-PET÷CT procedure. This investigation subsequently revealed a previously undetected metastatic lesion in the first cervical vertebra, with no signs of spinal cord compression. Treatment with a nonsteroidal anti-inflammatory drug reduced the symptoms sufficiently, and a few weeks later the neurosurgeon performed a complete resection of the metastasis. It is likely that the symptoms were caused by oedema and÷or increased blood flow to the lesion. Physicians should be aware that rhTSH administration to patients with disseminated thyroid carcinoma may lead to sudden onset of symptoms caused by previously occult metastases.

Purpose: To prospectively describe in a population of oncological second opinion patients: (1) the outcome of routine revisions of histopathological and radiological material, (2) the frequency and extent of discrepancy between the second and first opinion and (3) the location of further treatment or follow-up., Patients and Methods: In a population of 466 consecutive patients seeking a second opinion at the Surgical Oncology Outpatient Clinic, demographic and clinical patient characteristics were registered prospectively, as were the results of routine revision of histopathological and radiological material and the location of further treatment or follow-up. A classification system was developed to categorize the differences between the second and first opinion., Results: The mean age of the 403 eligible patients was 52 years. Most patients (87%) were women, of whom 83% were diagnosed with breast cancer. Revision of histopathological and radiological material was performed in 80 and 61% of the cases, respectively, and resulted in a major change in treatment or prognosis in 3 and 2% of patients, respectively. In 317 patients (79%), the second opinion could be compared with the first opinion, resulting in an identical advise in 68%, a minor discrepancy in 16% and a major discrepancy in another 16% of patients. For further treatment 78% of patients were referred back to their first specialist., Conclusion: One third of patient-initiated second opinion consultations resulted in a discrepancy with the first opinion. Half of these different advise lead to major changes in therapy or prognosis.

Members of the Dutch working group on soft tissue tumours developed an up-to-standard evidence-based multidisciplinary clinical practice guideline for the diagnosis of soft tissue tumours and the treatment and follow-up of soft tissue sarcomas, in cooperation with the Dutch Association of Comprehensive Cancer Centres and the Dutch Institute for Healthcare Improvement. A soft tissue sarcoma is defined as every non-epithelial tumour that does not originate in haematopoietic or lymphatic system, central nervous system or bone. The guideline lists 'alarm signals' to raise awareness of malignancy and recommends consulting a multidisciplinary team. Non-invasive imaging has to be completed before proceeding to any invasive (diagnostic) procedure or assessment of dissemination. Aspiration cytology can be useful for differentiating between sarcoma and other malignancies. A definite diagnosis is obtained by means of image-guided needle biopsy. Tumours will be classified according to the World Health Organization and graded according to the Federation Nationale des Centres de Lutte Contre le Cancer. Surgical excision with a tumour free margin of 2 cm is the core of therapy, taking into account vital structures when necessary. In case of small superficial tumours (diameter < or = 3 cm) excision biopsy may be justified. Radiotherapy is almost always necessary and certainly indicated when wide margins are impossible even after re-resection. In the case of primary metastatic disease, an individual decision should be taken after multi-disciplinary consultation concerning the possibility of curative or palliative treatment. Neither neo-adjuvant nor adjuvant chemotherapy is standard. Chemotherapy may be useful in metastatic disease. The guideline advises referring patients who are eligible for chemotherapy to a centre and that they should be included in a study protocol.

Rationale and Objectives: To show the impact of the introduction of multi-detector computed tomography (CT) on radiologic workflow and to demonstrate how this reflects on picture archiving and communications systems (PACS) requirements., Materials and Methods: Production measurements were obtained from different CT scanners (first two single-slice CT scanners; from December 2001 single and 4-slice CT; from April 2002 single and 16-slice CT) in number of patients from the radiologic information system. Implications on our PACS were recorded in terms of images and studies stored. Furthermore, our PACS design was made so that optimal use of 3-dimensional imaging within the radiologic workflow was possible. Finally, the number of non-diagnosed studies were recorded every day since the start of the transition to a filmless radiology department., Results: This PACS design achieved a high level of integration between simple viewing and advanced 3-dimensional imaging and is optimized for handling large amounts of data. Overall increase of patients scanned with CT from January 2002-December 2003 was 54%. The number of series increased by 286% from December 2001-April 2003 and by 130% from April 2002-December 2003. From January 2002-February 2003, the number of images per patient increased from 175 to 450 (157%). Non-diagnosed studies decreased from about 100-120 before to practically zero after PACS implementation., Conclusion: PACS significantly increases productivity because of availability of the images and elimination of certain manual tasks. These results show that although the amount of examinations increases significantly with the introduction of MDCT, simultaneous introduction of PACS and filmless operation allows radiologists to handle the growth in workload.

Objective: Three-dimensional data for noninvasive imaging of the coronary arteries are acquired from electron beam CT, multidetector CT, or MR imaging. Most commonly, surface rendering is used for three-dimensional processing, but recent advances in hardware and software technology have made it possible to use volume rendering. Our objective was to compare volume rendering with surface rendering for the visualization of the coronary artery tree., Conclusion: Our experience in the comparison of both techniques shows that because of intrinsic problems associated with surface rendering, volume rendering produces better image quality.