EANM guidelines for ventilation/perfusion scintigraphy

Abstract

Pulmonary embolism (PE) can only be diagnosed with imaging techniques, which in practice is performed using ventilation/perfusion scintigraphy (V/P(SCAN)) or multidetector computed tomography of the pulmonary arteries (MDCT). The epidemiology, natural history, pathophysiology and clinical presentation of PE are briefly reviewed. The primary objective of Part 1 of the Task Group's report was to develop a methodological approach to and interpretation criteria for PE. The basic principle for the diagnosis of PE based upon V/P(SCAN) is to recognize lung segments or subsegments without perfusion but preserved ventilation, i.e. mismatch. Ventilation studies are in general performed after inhalation of Krypton or technetium-labelled aerosol of diethylene triamine pentaacetic acid (DTPA) or Technegas. Perfusion studies are performed after intravenous injection of macroaggregated human albumin. Radiation exposure using documented isotope doses is 1.2-2 mSv. Planar and tomographic techniques (V/P(PLANAR) and V/P(SPECT)) are analysed. V/P(SPECT) has higher sensitivity and specificity than V/P(PLANAR). The interpretation of either V/P(PLANAR) or V/P(SPECT) should follow holistic principles rather than obsolete probabilistic rules. PE should be reported when mismatch of more than one subsegment is found. For the diagnosis of chronic PE, V/P(SCAN) is of value. The additional diagnostic yield from V/P(SCAN) includes chronic obstructive lung disease (COPD), heart failure and pneumonia. Pitfalls in V/P(SCAN) interpretation are considered. V/P(SPECT) is strongly preferred to V/P(PLANAR) as the former permits the accurate diagnosis of PE even in the presence of comorbid diseases such as COPD and pneumonia. Technegas is preferred to DTPA in patients with COPD.

Diagnosing venous thromboembolism in pregnancy

“…16 The European Association of Nuclear Medicine (EANM) have recently produced guidelines 17,18 which have led to a more extensive interest in its use. Whilst there have been considerable studies on the diagnostic performance of "traditional" planar VQ scans, most commonly by the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) trials and their subsequent reanalyses, [19][20][21] available data for VQ SPECT are inhomogeneous in terms of the ventilation tracer used and the reporting criteria.…”

Lung perfusion: MRI vs. SPECT for screening in suspected chronic thromboembolic pulmonary hypertension

“…SPECT imaging represents deposition of radio‐isotope particles in the capillaries and small arterioles in the lung,9 with acquisition times around 10 minutes in a pseudosteady‐state of lung perfusion. DCE MR perfusion images are, however, dynamically acquired in the first pass of gadolinium; and a 3D dataset is acquired (here, approximately every 0.5 sec) during a breath‐hold.…”

“…It is important that the diagnosis of CTEPH is made, as pulmonary endarterectomy is associated with increased survival and a favorable functional outcome in CTEPH 1. The 2013 World Symposium on Pulmonary Hypertension recommended single photon emission computed tomography (SPECT) ventilation/perfusion (V/Q) scintigraphy as the preferred screening test for CTEPH,8 but this entails injection of 100 MBq of 99mTc‐labeled macroaggregated human albumin, resulting in exposure to ionizing radiation with an effective dose of 0.017 mSv/MBq 9…”

The Economic Value of Hybrid Single‐photon Emission Computed Tomography With Computed Tomography Imaging in Pulmonary Embolism Diagnosis

“…Acute PE is a potentially fatal disease with mortality between 10 and 30% if untreated 4, 5. Although various symptoms, signs, laboratory tests, and/or predisposing patient factors can be used to formulate a clinical likelihood of PE, these parameters are often nonspecific6, 7 making PE diagnosis very challenging even in a highly suspected case.…”

“…V/Q single‐photon emission computed tomography (V/Q SPECT), which utilizes three‐dimensional nuclear medicine imaging of ventilation and perfusion, is an underutilized but valuable tool to evaluate and quantify the extent of acute PE, as well as establish alternate diagnoses 10. The imaging practice guidelines of the Society of Nuclear Medicine detail the advantage of using SPECT to obtain a three‐dimensional evaluation of the lungs,11 while the European Association of Nuclear Medicine guidelines recommend V/Q SPECT as the preferred modality whenever possible 4. Despite its high diagnostic accuracy, the use of SPECT for evaluation of acute PE remains limited 12.…”