A guide for a brave future for lung ventilation/perfusion tomography: the most important pulmonary nuclear medicine technique

Excerpt

Until this century, planar imaging was the primary non-invasive method for the diagnosis of pulmonary embolism (PE). This historical technique combined with so-called probabilistic interpretation suffered disrepute since the PIOPED I study showed that 65% of scans were non-diagnostic [1]. The European Association of Nuclear Medicine (EANM) guideline written by Bajc et al. [2] is a state-of-the-art guideline of the most important pulmonary nuclear medicine technique. This seminal work updates the EANM’s previous and first guideline for ventilation/perfusion scintigraphy (V/P) published in 2009 [3, 4]. A decade ago, in 2009, the EANM guideline had already determined that the principle of probabilistic diagnosis was obsolete based on the overwhelming superiority of V/P single-photon emission computed tomography (SPECT) combined with a holistic interpretation [3, 4]. The improved technique reduced the number of non-diagnostic findings to 4% or less, while sensitivity and specificity were excellent [5]. Recent V/P_SPECT studies have shown that interpretation of all patterns representing ventilation, together with perfusion, achieves conclusive reports in 97 to 99% of cases [6, 7]. The ability to quantify the regional ventilation and perfusion gives pulmonary V/P_SPECT the paramount role of nuclear imaging techniques when leveraging the knowledge of lung physiology together with pathophysiology. Ventilation imaging maps regional ventilation and helps define lung borders, thereby facilitating the recognition of peripheral perfusion defects. Furthermore, the ventilation scan is essential in providing additional information about cardiopulmonary disorders beyond PE such as chronic obstructive pulmonary disease (COPD), asthma, pneumonia, and left heart failure and in clinically challenging situations such as chronic pulmonary embolism and chronic thromboembolic pulmonary hypertension (CTEPH). A combined 1-day V/P study is recommended as it increases the specificity for PE diagnosis and allows the detection of additional pathology [2]. In this respect, ventilation imaging has an invaluable role as part of the lung V/P scintigraphy. V/P_SPECT has a key role in diagnosing PE in pregnant women. …