Pitfalls and artifacts using the D-SPECT dedicated cardiac camera

Abstract

Myocardial perfusion imaging (MPI) is a well-established and widely used imagingtechnique for the assessment of patients with known or suspected coronary artery disease. Pitfalls and artifacts associated with conventional gamma cameras are well known and the ways to avoid and correct them have been described. In recent years solid-state detector dedicated cardiac cameras were introduced and have been shown to offer improved accuracy in addition to new imaging protocols and novel applications. The purpose of this manuscript is to familiarize the readers with the causes and effects of technical, patient related and operator-related pitfalls and artifacts associated with the D-SPECT dedicated cardiac camera with solid-state detectors. The manuscript offers guidance on how to avoid these factors, how to detect them and how to correct better for them, providing high-quality diagnostic images.

D-SPECT: New technology, old tricks

“…6 Their paper is based on single-center experience and is largely qualitative, but is nevertheless a useful resource for those new to cardiac CZT technology on the recognition and troubleshooting of common technical artifacts in clinical practice.…”

“…7 Allie et al provide some examples of breast and diaphragmatic attenuation artifacts which illustrates the benefits of patient repositioning. 6 Notably, the Discovery NM/CT 570c (GE Healthcare) camera has an integrated CT which provides an efficient platform for CT attenuation correction, coronary calcium scoring, or even CT coronary angiography in the same sitting. The added cost of such a system limits its availability, and both the Discovery series and D-SPECT can use CT data acquired on another camera to be integrated with the SPECT imaging from the CZT acquisition.…”

“…However, this approach is not feasible for dedicated cardiac CZT cameras due to different hardware setup. Instead, dedicated cardiac CZT cameras rely on sinogram analysis for motion detection, and some examples are provided by Allie et al 6 On NaI SPECT cameras, minor motion artifacts may be managed by motion-correction software suited to different camera systems, while significant motion usually requires repeat imaging. On the CZT systems, repeat imaging is required, but, as pointed out, can be quickly performed.…”

“…Allie et al also have examples of other artifacts, e.g., detector failure, sub-diaphragmatic scatter, and region-of-interest delineation, which will be useful for new users of the D-SPECT. 6 The cardiac-centric design of dedicated cardiac CZT cameras confers many advantages, but is also its Achilles heel. It may be difficult to position the heart of a very large patient in the center of the field-of-view.…”

“…Even metropolitan Nuclear Medicine centers may not have sufficient Nuclear Cardiology throughput to economically justify the purchase and running costs of a dedicated cardiac CZT camera. We welcome the manuscript of Allie and colleagues 6 as a valuable reference for the new user of this technology. New technology is always exciting, but let's not forget that the versatility of the standard NaI SPECT camera has made it the workhorse of Nuclear Medicine for decades, and will likely remain so for many more years to come.…”