Quantification of myocardial blood flow with 82Rb positron emission tomography: clinical validation with 15O-water.

PURPOSE: Quantification of myocardial blood flow (MBF) with generator-produced (82)Rb is an attractive alternative for centres without an on-site cyclotron. Our aim was to validate (82)Rb-measured MBF in relation to that measured using (15)O-water, as a tracer 100% of which can be extracted from the circulation even at high flow rates, in healthy control subject and patients with mild coronary artery disease (CAD). METHODS: MBF was measured at rest and during adenosine-induced hyperaemia with (82)Rb and (15)O-water PET in 33 participants (22 control subjects, aged 30 ± 13 years; 11 CAD patients without transmural infarction, aged 60 ± 13 years). A one-tissue compartment (82)Rb model with ventricular spillover correction was used. The (82)Rb flow-dependent extraction rate was derived from (15)O-water measurements in a subset of 11 control subjects. Myocardial flow reserve (MFR) was defined as the hyperaemic/rest MBF. Pearson's correlation r, Bland-Altman 95% limits of agreement (LoA), and Lin's concordance correlation ρ (c) (measuring both precision and accuracy) were used. RESULTS: Over the entire MBF range (0.66-4.7 ml/min/g), concordance was excellent for MBF (r = 0.90, [(82)Rb-(15)O-water] mean difference ± SD = 0.04 ± 0.66 ml/min/g, LoA = -1.26 to 1.33 ml/min/g, ρ(c) = 0.88) and MFR (range 1.79-5.81, r = 0.83, mean difference = 0.14 ± 0.58, LoA = -0.99 to 1.28, ρ(c) = 0.82). Hyperaemic MBF was reduced in CAD patients compared with the subset of 11 control subjects (2.53 ± 0.74 vs. 3.62 ± 0.68 ml/min/g, p = 0.002, for (15)O-water; 2.53 ± 1.01 vs. 3.82 ± 1.21 ml/min/g, p = 0.013, for (82)Rb) and this was paralleled by a lower MFR (2.65 ± 0.62 vs. 3.79 ± 0.98, p = 0.004, for (15)O-water; 2.85 ± 0.91 vs. 3.88 ± 0.91, p = 0.012, for (82)Rb). Myocardial perfusion was homogeneous in 1,114 of 1,122 segments (99.3%) and there were no differences in MBF among the coronary artery territories (p > 0.31). CONCLUSION: Quantification of MBF with (82)Rb with a newly derived correction for the nonlinear extraction function was validated against MBF measured using (15)O-water in control subjects and patients with mild CAD, where it was found to be accurate at high flow rates. (82)Rb-derived MBF estimates seem robust for clinical research, advancing a step further towards its implementation in clinical routine.

Dual-wavelength digital holographic microscopy with sub-nanometer axial accuracy

We present dual-wavelength Digital Holographic Microscopy (DHM) measurements on a certified 8.9 nm high Chromium thin step sample and demonstrate sub-nanometer axial accuracy. We introduce a modified DHM Reference Calibrated Hologram (RCH) reconstruction algorithm taking into account amplitude contributions. By combining this with a temporal averaging procedure and a specific dual-wavelength DHM arrangement, it is shown that specimen topography can be measured with an accuracy, defined as the axial standard deviation, reduced to at least 0.9 nm. Indeed, it is reported that averaging each of the two wavefronts recorded with real-time dual-wavelength DHM can provide up to 30% spatial noise reduction for the given configuration, thanks to their non-correlated nature. ©2008 COPYRIGHT SPIE

Warning systems in a computerized nursing process for Intensive Care Units

A hybrid study combining technological production and methodological research aiming to establish associations between the data and information that are part of a Computerized Nursing Process according to the ICNP® Version 1.0, indicators of patient safety and quality of care. Based on the guidelines of the Agency for Healthcare Research and Quality and the American Association of Critical Care Nurses for the expansion of warning systems, five warning systems were developed: potential for iatrogenic pneumothorax, potential for care-related infections, potential for suture dehiscence in patients after abdominal or pelvic surgery, potential for loss of vascular access, and potential for endotracheal extubation. The warning systems are a continuous computerized resource of essential situations that promote patient safety and enable the construction of a way to stimulate clinical reasoning and support clinical decision making of nurses in intensive care.

Diagnostic performance of &supl;⁸F-fluorodeoxyglucose positron emission tomography in giant cell arteritis: a systematic review and meta-analysis.

PURPOSE: The aim of this study was to conduct a systematic review and perform a meta-analysis on the diagnostic performances of (18)F-fluorodeoxyglucose positron emission tomography (FDG PET) for giant cell arteritis (GCA), with or without polymyalgia rheumatica (PMR). METHODS: MEDLINE, Embase and the Cochrane Library were searched for articles in English that evaluated FDG PET in GCA or PMR. All complete studies were reviewed and qualitatively analysed. Studies that fulfilled the three following criteria were included in a meta-analysis: (1) FDG PET used as a diagnostic tool for GCA and PMR; (2) American College of Rheumatology and Healey criteria used as the reference standard for the diagnosis of GCA and PMR, respectively; and (3) the use of a control group. RESULTS: We found 14 complete articles. A smooth linear or long segmental pattern of FDG uptake in the aorta and its main branches seems to be a characteristic pattern of GCA. Vessel uptake that was superior to liver uptake was considered an efficient marker for vasculitis. The meta-analysis of six selected studies (101 vasculitis and 182 controls) provided the following results: sensitivity 0.80 [95% confidence interval (CI) 0.63-0.91], specificity 0.89 (95% CI 0.78-0.94), positive predictive value 0.85 (95% CI 0.62-0.95), negative predictive value 0.88 (95% CI 0.72-0.95), positive likelihood ratio 6.73 (95% CI 3.55-12.77), negative likelihood ratio 0.25 (95% CI 0.13-0.46) and accuracy 0.84 (95% CI 0.76-0.90). CONCLUSION: We found overall valuable diagnostic performances for FDG PET against reference criteria. Standardized FDG uptake criteria are needed to optimize these diagnostic performances.

Radioimmuno positron emission tomography with monoclonal antibodies: a new approach to quantifying in vivo tumour concentration and biodistribution for radioimmunotherapy.

Radioimmunodetection of tumours with monoclonal antibodies is becoming an established procedure. Positron emission tomography (PET) shows better resolution than normal gamma camera single photon emission tomography and can provide more precise quantitative data. Thus, in the present study, these powerful methods have been combined to perform radioimmuno PET (RI-PET). Monoclonal antibodies directed against carcinoembryonic antigen (CEA) an IgG, its F(ab')2 and a mouse-human chimeric IgG derived from it were labelled with 124I, a positron-emitting radionuclide with a convenient physical half-life of four days. Mice, xenografted with a CEA-producing human colon carcinoma, were injected with the 124I-MAb and the tumours were visualized using PET. The concentrations of 124I in tumour and normal tissue were determined by both PET and direct radioactivity counting of the dissected animals, with very good agreement. To allow PET quantification, a procedure was established to account for the presence of radioactivity during the absorption correction measurement (transmission scan). Comparison of PET and tissue counting indicates that this novel combination of radioimmunolocalization and PET (RI-PET) will provide, in addition to more precise diagnosis, more accurate radiation dosimetry for radioimmunotherapy.

Ictal cerebral positron emission tomography (PET) in focal status epilepticus.

The diagnosis of focal status epilepticus (SE) can be challenging, particularly when clinical manifestations leave doubts about its nature, and electroencephalography (EEG) is not conclusive. This work addresses the utility of ictal (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) in focal SE, which was performed in eight patients in whom SE was finally diagnosed. Clinical, MRI and EEG data were reviewed. (18)F-FDG-PET proved useful: (1) to establish the diagnosis of focal SE, when clinical elements were equivocal or the EEG did not show clear-cut epileptiform abnormalities; (2) to delineate the epileptogenic area in view of possible resective surgery; and (3) when clinical features, MRI and EEG were incongruent regarding the origin of SE. We suggest that ictal (18)F-FDG-PET may represent a valuable diagnostic tool in selected patients with focal SE or frequent focal seizures.

Imaging of tophaceous gout: computed tomography provides specific images compared with magnetic resonance imaging and ultrasonography.

OBJECTIVE: To determine the usefulness of computed tomography (CT), magnetic resonance imaging (MRI), and Doppler ultrasonography (US) in providing specific images of gouty tophi. METHODS: Four male patients with chronic gout with tophi affecting the knee joints (three cases) or the olecranon processes of the elbows (one case) were assessed. Crystallographic analyses of the synovial fluid or tissue aspirates of the areas of interest were made with polarising light microscopy, alizarin red staining, and x ray diffraction. CT was performed with a GE scanner, MR imaging was obtained with a 1.5 T Magneton (Siemens), and ultrasonography with colour Doppler was carried out by standard technique. RESULTS: Crystallographic analyses showed monosodium urate (MSU) crystals in the specimens of the four patients; hydroxyapatite and calcium pyrophosphate dihydrate (CPPD) crystals were not found. A diffuse soft tissue thickening was seen on plain radiographs but no calcifications or ossifications of the tophi. CT disclosed lesions containing round and oval opacities, with a mean density of about 160 Hounsfield units (HU). With MRI, lesions were of low to intermediate signal intensity on T(1) and T(2) weighting. After contrast injection in two cases, enhancement of the tophus was seen in one. Colour Doppler US showed the tophi to be hypoechogenic with peripheral increase of the blood flow in three cases. CONCLUSION: The MR and colour Doppler US images showed the tophi as masses surrounded by a hypervascular area, which cannot be considered as specific for gout. But on CT images, masses of about 160 HU density were clearly seen, which correspond to MSU crystal deposits.

Usability of computerized nursing process from the ICNP® in intensive care units

OBJECTIVE To analyze the usability of Computerized Nursing Process (CNP) from the ICNP® 1.0 in Intensive Care Units in accordance with the criteria established by the standards of the International Organization for Standardization and the Brazilian Association of Technical Standards of systems. METHOD This is a before-and-after semi-experimental quantitative study, with a sample of 34 participants (nurses, professors and systems programmers), carried out in three Intensive Care Units. RESULTS The evaluated criteria (use, content and interface) showed that CNP has usability criteria, as it integrates a logical data structure, clinical assessment, diagnostics and nursing interventions. CONCLUSION The CNP is a source of information and knowledge that provide nurses with new ways of learning in intensive care, for it is a place that provides complete, comprehensive, and detailed content, supported by current and relevant data and scientific research information for Nursing practices.

Post-axial polydactyly type A2, overgrowth and autistic traits associated with a chromosome 13q31.3 microduplication encompassing miR-17-92 and GPC5.

Genomic rearrangements at chromosome 13q31.3q32.1 have been associated with digital anomalies, dysmorphic features, and variable degree of mental disability. Microdeletions leading to haploinsufficiency of miR17∼92, a cluster of micro RNA genes closely linked to GPC5 in both mouse and human genomes, has recently been associated with digital anomalies in the Feingold like syndrome. Here, we report on a boy with familial dominant post-axial polydactyly (PAP) type A, overgrowth, significant facial dysmorphisms and autistic traits who carries the smallest germline microduplication known so far in that region. The microduplication encompasses the whole miR17∼92 cluster and the first 5 exons of GPC5. This report supports the newly recognized role of miR17∼92 gene dosage in digital developmental anomalies, and suggests a possible role of GPC5 in growth regulation and in cognitive development.

Computerized advice on drug dosage to improve prescribing practice.

BACKGROUND: Maintaining therapeutic concentrations of drugs with a narrow therapeutic window is a complex task. Several computer systems have been designed to help doctors determine optimum drug dosage. Significant improvements in health care could be achieved if computer advice improved health outcomes and could be implemented in routine practice in a cost effective fashion. This is an updated version of an earlier Cochrane systematic review, by Walton et al, published in 2001. OBJECTIVES: To assess whether computerised advice on drug dosage has beneficial effects on the process or outcome of health care. SEARCH STRATEGY: We searched the Cochrane Effective Practice and Organisation of Care Group specialized register (June 1996 to December 2006), MEDLINE (1966 to December 2006), EMBASE (1980 to December 2006), hand searched the journal Therapeutic Drug Monitoring (1979 to March 2007) and the Journal of the American Medical Informatics Association (1996 to March 2007) as well as reference lists from primary articles. SELECTION CRITERIA: Randomized controlled trials, controlled trials, controlled before and after studies and interrupted time series analyses of computerized advice on drug dosage were included. The participants were health professionals responsible for patient care. The outcomes were: any objectively measured change in the behaviour of the health care provider (such as changes in the dose of drug used); any change in the health of patients resulting from computerized advice (such as adverse reactions to drugs). DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and assessed study quality. MAIN RESULTS: Twenty-six comparisons (23 articles) were included (as compared to fifteen comparisons in the original review) including a wide range of drugs in inpatient and outpatient settings. Interventions usually targeted doctors although some studies attempted to influence prescriptions by pharmacists and nurses. Although all studies used reliable outcome measures, their quality was generally low. Computerized advice for drug dosage gave significant benefits by:1.increasing the initial dose (standardised mean difference 1.12, 95% CI 0.33 to 1.92)2.increasing serum concentrations (standradised mean difference 1.12, 95% CI 0.43 to 1.82)3.reducing the time to therapeutic stabilisation (standardised mean difference -0.55, 95%CI -1.03 to -0.08)4.reducing the risk of toxic drug level (rate ratio 0.45, 95% CI 0.30 to 0.70)5.reducing the length of hospital stay (standardised mean difference -0.35, 95% CI -0.52 to -0.17). AUTHORS' CONCLUSIONS: This review suggests that computerized advice for drug dosage has some benefits: it increased the initial dose of drug, increased serum drug concentrations and led to a more rapid therapeutic control. It also reduced the risk of toxic drug levels and the length of time spent in the hospital. However, it had no effect on adverse reactions. In addition, there was no evidence to suggest that some decision support technical features (such as its integration into a computer physician order entry system) or aspects of organization of care (such as the setting) could optimise the effect of computerised advice.

Radioimmunotherapy of colorectal cancer liver metastases: combination with radiotherapy.

The expected therapeutic gain of a combined radioimmunotherapy (RIT) with conventional radiotherapy (RT) would be a synergy of tumor irradiation, provided that toxic, dose-limiting side effects concern different organs. We have shown in a model of subcutaneous human colon cancer transplants in nude mice that RIT with 131I-labeled anti-CEA antibody fragments combined with fractionated RT give an additive therapeutic effect without increase of side effects. A second study of different timing schedules of RIT and RT has shown that close association of both therapies without delay is more efficient than a therapy with a treatment-free interval of two weeks. In a new model of human colon cancer liver metastases in nude mice, early treatment with RIT and with RT has been curative, whereas therapies initiated later were less efficient, suggesting that the combined therapy is likely to be more efficient in an adjuvant situation after surgery. At the clinical level, six patients with limited liver metastatic disease from colorectal cancer were treated with RIT using 200 mCi 131I-labeled anti-CEA MAb F(ab')2 fragments combined with fractionated external beam RT of 20 Gy to the entire liver. As expected, spontaneously reversible bone marrow toxicity grade 3 to 4 and reversible liver toxicity grade 1 to 3 have been observed. By computerized tomography, three patients showed stable disease and one patient partial remission, whereas two patients had progressive disease. In conclusion, animal experiments have shown a clear advantage of combined RT and RIT, and the clinical study shows the feasibility of such a therapy in patients with colorectal cancer liver metastases.

Transthoracic adrenal biopsy procedure using artificial carbon dioxide pneumothorax as outpatient procedure.

Many routes have been described for percutaneous adrenal gland biopsy. They require either a complex non-axial path or a long hydrodissection or even pass through an organ thereby increasing complications. We describe here an approach using an artificially-induced carbon dioxide (CO2) pneumothorax, performed as an outpatient procedure in a 57-year-old woman. Under local anaesthesia, 200 ml of CO2 was injected in the pleural space through a Veress needle under computed tomography fluoroscopy, to clear the lung parenchyma from the biopsy route. Using this technique, transthoracic adrenal biopsy can be performed under simple local anaesthesia as an safely outpatient procedure.

Direct MR arthrography of the shoulder under axial traction: Feasibility study to evaluate the superior labrum-biceps tendon complex and articular cartilage.

PURPOSE: To assess the value of adding axial traction to direct MR arthrography of the shoulder, in terms of subacromial and glenohumeral joint space widths, and coverage of the superior labrum-biceps tendon complex and articular cartilage by contrast material. MATERIALS AND METHODS: Twenty-one patients investigated by direct MR arthrography of the shoulder were prospectively included. Studies were performed with a 3 Tesla (T) unit and included a three-dimensional isotropic fat-suppressed T1-weighted gradient-recalled echo sequence, without and with axial traction (4 kg). Two radiologists independently measured the width of the subacromial, superior, and inferior glenohumeral joint spaces. They subsequently rated the amount of contrast material around the superior labrum-biceps tendon complex and between glenohumeral cartilage surfaces, using a three-point scale: 0 = no, 1 = partial, 2 = full. RESULTS: Under traction, the subacromial (Δ = 2.0 mm, P = 0.0003), superior (Δ = 0.7 mm, P = 0.0001) and inferior (Δ = 1.4 mm, P = 0.0006) glenohumeral joint space widths were all significantly increased, and both readers noted significantly more contrast material around the superior labrum-biceps tendon complex (P = 0.014), and between the superior (P = 0.001) and inferior (P = 0.025) glenohumeral cartilage surfaces. CONCLUSION: Direct MR arthrography of the shoulder under axial traction increases subacromial and glenohumeral joint space widths, and prompts better coverage of the superior labrum-biceps tendon complex and articular cartilage by contrast material. J. Magn. Reson. Imaging 2013;37:1228-1233. © 2012 Wiley Periodicals, Inc.