Dual-energy computed tomography in crystalline arthritis: knowns and unknowns

Abstract

Purpose of reviewTo give an overview of what can reasonably be considered as known about dual-energy computed tomography (DECT) in crystal-related arthropathies, and what still needs to be explored. Recent findingsRecent studies suggest an overall superiority of DECT over ultrasound in gout in terms of sensitivity (89 vs. 84%) and specificity (91 vs. 84%), except in early disease. Additional studies are needed to optimize DECT postprocessing settings in order to improve the specificity of the technique and eliminate all artifacts. Evidence has been controversial concerning DECT's ability to detect monosodium urate (MSU) crystal deposits on vessel walls, or whether or not MSU-coded plaques are artifacts. DECT can be used to monitor MSU crystal depletion during urate-lowering treatment; MSU crystal volume is associated with cardiovascular risk and disease activity. There are some reports on calcium-containing crystal deposition diseases (calcium pyrophosphate and basic calcium phosphate) demonstrating that DECT can characterize and discriminate between the different types of crystals. SummaryOur knowledge about the use of DECT in crystal-related arthropathies continues to expand. Some unknowns have been clarified but there's still lots to learn, particularly concerning gout management and the potential use of DECT in calcium-containing crystal-related arthropathies.

The Clinical Utility of Dual-Energy Computed Tomography in the Diagnosis of Gout—A Cross-Sectional Study

“…This could give false-positive results. Although there are studies that have attempted to optimize DECT post-processing settings to reduce artifacts, additional studies are needed to improve the automatic elimination of all artifacts [ 6 , 7 , 8 , 16 , 17 , 18 , 19 ].…”

Describing calcium pyrophosphate deposition: undoing the tower of Babel!

“…In this section, we focus on conventional radiography and ultrasound, which have predominantly contributed to the definition and characterization of CPPD. More advanced imaging techniques, such as DECT and multi energy spectral photon-counting CT (SPCCT) [30,31], have made significant progress in recent years towards identifying CPPD, but they currently offer limited data in a large series of patients, and to date, they do not offer a real added value in characterizing CPPD when compared to ultrasound or radiography. We are confident that in the near future, these techniques will significantly contribute to gaining deeper insights of the disease's clinical impact and pathogenesis.…”