EANM guideline for ventilation/perfusion single-photon emission computed tomography (SPECT) for diagnosis of pulmonary embolism and beyond.

These guidelines update the previous EANM 2009 guidelines on the diagnosis of pulmonary embolism (PE). Relevant new aspects are related to (a) quantification of PE and other ventilation/perfusion defects; (b) follow-up of patients with PE; (c) chronic PE; and (d) description of additional pulmonary physiological changes leading to diagnoses of left ventricular heart failure (HF), chronic obstructive pulmonary disease (COPD) and pneumonia. The diagnosis of PE should be reported when a mismatch of one segment or two subsegments is found.

Diagnosing venous thromboembolism in pregnancy.

Objective: We report the imaging outcomes of all pregnant patients referred for suspected thromboembolism over a 43-month period.

Methods: We identified 168 patients who underwent ventilation/perfusion (VQ) single-photon emission CT (SPECT), CT pulmonary angiography (CTPA) or a Doppler ultrasound scan of the lower legs, as well as a control group of 89 non-pregnant age- and sex-matched patients who underwent VQ SPECT during the same period. Imaging outcomes were recorded, and radiation doses were calculated for individual patients.

Three-year clinical experience with VQ SPECT for diagnosing pulmonary embolism: diagnostic performance.

Ventilation-perfusion (VQ) single-photon emission computed tomography (SPECT) comprised the administration of SmartVent (n=386) or Technegas (n=1564) and 200 MBq (99m)Tc-MAA. 1406 scans were normal, 462 showed PE, 61 showed a singular subsegmental mismatched defect, 21 scans were non-diagnostic. 26% of scans performed with Technegas showed PE, compared to 15% with SmartVent.

Higher extracellular fluid volume in women is concealed by scaling to body surface area.

Objective: The objective was to assess body surface area (BSA) for scaling extracellular fluid volume (ECV) in comparison with estimated lean body mass (LBM) and total body water (TBW) across a range of body mass indices (BMI).

Methods: This was a multi-centre study from 15 centres that submitted raw data from routine measurement of GFR in potential kidney transplant donors. There were 819 men and 1059 women in total.

Efficacy of various SPECT reconstruction algorithms in differentiating bowel uptake from inferior wall uptake in myocardial perfusion scans.

Objective: Bowel uptake is a frequent artefact in myocardial perfusion scans (MPS) that can impede the assessment of the inferior wall, necessitating repeat acquisitions. This study is a retrospective analysis of MPS reconstructed with different algorithms to see whether corrections for scatter or depth-dependent loss of resolution may help differentiate apparently joined uptake in the inferior wall of the left ventricle from that in the bowel.

Methods: A total of 79 sequential stress MPS acquired 1 h after injection of 600 MBq Tc-tetrofosmin on a Siemens Symbia T were reconstructed using filtered back projection (FBP), iteratively with ordered subset expectation maximization (OSEM) and iteratively with three-dimensional collimator beam modelling (Siemens Flash3D), Flash3D with scatter correction (SC) and/or attenuation correction (AC).

Resolution recovery in planar bone scans: diagnostic value in metastatic disease.

Recovery of spatial resolution lost through increasing lesion-to-detector distance can improve the spatial resolution of planar images. We compare two commercial solutions, HiScan (http://www.scivis.

The reliability of glomerular filtration rate measured from plasma clearance: a multi-centre study of 1,878 healthy potential renal transplant donors.

Purpose: The objective of the study was to undertake a clinical audit of departmental performance in the measurement of glomerular filtration rate (GFR) using the coefficient of variation (CV) of extracellular fluid volume (ECFV) as the benchmark. ECFV is held within narrow limits in healthy subjects, narrower than GFR, and should therefore have a low CV.

Methods: Fifteen departments participated in this retrospective study of healthy renal transplant donors.

Extracellular fluid volume and glomerular filtration rate in 1878 healthy potential renal transplant donors: effects of age, gender, obesity and scaling.

Unlabelled: Aim. The aim of this study was to investigate the influence of age, gender, obesity and scaling on glomerular filtration rate (GFR) and extracellular fluid volume (ECV) in healthy subjects.

Methods: This is a retrospective multi-centre study of 1878 healthy prospective kidney transplant donors (819 men) from 15 centres.

Can plasma D-dimer predict the result of a ventilation-perfusion scan?

The use of plasma D-dimer assay has been advocated for the exclusion of pulmonary embolism. We retrospectively looked at 840 patients in whom both ventilation-perfusion scan and D-dimer assay were performed within 48 h. The negative predictive value of a negative D-dimer assay was 96% for emergency admissions and 98% for inpatients.

On specificity of 2nd generation TSH receptor autoantibody measurements.

Background: TSH receptor (TSHR) antibodies (TRAb) are the hallmark in the serological diagnosis of Graves' disease (autoimmune hyperthyroidism). Irrespective of receptor origin second generation TRAb assays have been shown to be more sensitive than original first generation assays. The specificity of both assay generations is claimed to be close to 100% for discriminating healthy individuals from Graves' disease patients.

Influence of female sex hormones on thyroid parameters determined in a thyroid screening.

This is a cross-sectional study with a non-randomly selected population to ascertain the influence of female sex hormones on thyroid function. TSH, TT4, FT4, TT3 and FT3 were determined in 251 women using either oral hormonal contraceptives or hormone replacement treatment, 255 women not taking either, and a control group of 900 men. Women with normal thyroid morphology using oral hormonal contraceptives in the pre-menopausal group had a significantly higher TT4 and TT3, and lower FT3, respectively, than both non-users and men.

Can administration of metoclopramide reduce artefacts related to abdominal activity in myocardial perfusion SPECT?

Objectives: Myocardial perfusion SPECT is frequently affected by artefacts related to abdominal activity. Metoclopramide has been suggested to relieve this, but two previous studies have shown conflicting results.

Methods: Ninety-five patients received 10 mg metoclopramide orally after injection of 99mTc-tetrofosmin for the stress scan and 86 patients had metoclopramide after their rest injection.

X-ray-based attenuation correction of myocardial perfusion scans: practical feasibility and diagnostic impact.

Objectives: This study describes the practical implementation of X-ray-based attenuation correction (AC) of myocardial perfusion scans in a large teaching hospital, characterizes the impact of AC on the diagnostic confidence of the interpreter and tries to predict which patients are likely to benefit from the technique.

Methods: One hundred and seven consecutive patients underwent a 2 day (99m)Tc-tetrofosmin protocol with adenosine stress using GE Millennium VG with AC and ECG-gated acquisition (ECG-g). The diagnostic impact of AC/ECG-g was judged by a panel of three observers.

18F-FDG PET for detecting myocardial viability: validation of 3D data acquisition.

Unlabelled: (18)F-FDG PET is an important diagnostic tool for detecting myocardial viability in patients with coronary artery disease. In combination with perfusion scanning, (18)F-FDG PET allows differentiation between reversibly and irreversibly damaged myocardium and selection of patients likely to benefit from revascularization. Viability PET is usually performed in two-dimensional (2D) mode.

99mTc labelled model drug carriers - labeling, stability and organ distribution in rats.

The surface characteristics of intravenously administered particulate drug carriers decisively influence the protein adsorption that is regarded as a key factor for the in vivo fate of the carriers. We labeled surface-modified polymer particles with the gamma-emitting radioisotope 99mTc in order to test their properties in blood and follow their in vivo fate. The biodistribution was different in various types of polymer particles.

Autoantibodies to thyroperoxidase (TPOAb) in a large population of euthyroid subjects: implications for the definition of TPOAb reference intervals.

Objective: Measurement of autoantibodies against thyroperoxidase (TPOAb) plays an important role in the diagnosis of autoimmune thyroid disease. The assessment of reference intervals for TPOAb, however, is a controversial issue since elevated TPOAb values are sometimes found in subjects without other evidence of thyroid disease.

Methods: TPOAb were measured in 1,295 euthyroid individuals using a highly sensitive, fully automated chemiluminescence assay (Advantage A-TPO, Nichols Institute Diagnostics, CA, USA).

Retinoic acid for redifferentiation of thyroid cancer--does it hold its promise?

Objectives: To evaluate the effectiveness of isotretinoin for improving (131)I uptake in recurrent/metastasized thyroid cancer with no/insufficient (131)I uptake.

Design: Retrospective analysis of 25 patients treated between June 1999 and May 2001.

Methods: 15 female and 10 male patients were given isotretinoin at 1 mg/kg for 3 months, followed by (131)I treatment.