Spectral CT in kidney evaluation, a pictorial review
Number:28ESURABS0041
Type:Educational Electronic Presentation
Authors: Tomás França de Santana, João Lopes Dias, António Pedro Matos, José Laert, José Sardinha
Keywords:Dual-energy CT, Spectral CT, Kidney evaluation, VMI, Material specific maps, VNC
SECTIONS
Educational objective

Describing the advantages Spectral Computed Tomography (SCT) can provide in tomodensitometric kidney evaluation in comparison to standard Computed Tomography (CT) using examples from clinical practice.

Topic Review

CT is widely used for kidney assessment. Main indications include urolithiasis evaluation and renal tumor characterization.

SCT is one of the most recent advances in CT. CT Scanners with spectral analysis capability can be source-based, using X-ray beams with different energy levels, or detector-based, relying on the detection of different energy levels in X-ray photons. Spectral analysis is based on different x-ray photon interactions with matter at different energy levels. The fact that different materials have different attenuation coefficients at different energy levels can be leveraged, through a myriad of post-processing techniques, to produce several sub-sets of images that can provide a significant amount of additional information. [1]

In addition to the usual CT images, SCT acquisitions allow the production of the following subsets of series: virtual...

...read more

Fig. 1 Axial VNC image reconstructed after intravenous iodinated contrast administration. A 3 mm renal stone is evident in the left kidney´s middle caliceal group (arrow).
Fig. 2 Axial non-contrast enhanced SCT acquisition (A). Respective Uric acid/HAP map (B) and HAP/uric acid map (C) reconstructed from the spectral acquisition data-file. Coraliform urolithiasis involving the left kidney’s middle and lower caliceal groups (arrow). Uric acid/HAP and HAP/uric acid maps revealing the stone´s poor uric acid content (black in B) and its rich HAP content (white in C).
Conclusions

SCT provides additional value in kidney evaluation, namely in renal mass characterization and urolithiasis detection/compositional analysis. Adequate use of this technique also may also allow radiation and contrast dose reductions. 

 

 

References:

[1] So A, Nicolaou S. Spectral Computed Tomography: Fundamental Principles and Recent Developments. Korean J Radiol. 2021 Jan;22(1):86-96. doi: 10.3348/kjr.2020.0144. Epub 2020 Sep 10. PMID: 32932564; PMCID: PMC7772378.

[2] Vrtiska TJ, Takahashi N, Fletcher JG, Hartman RP, Yu L, Kawashima A. Genitourinary applications of dual-energy CT. AJR Am J Roentgenol. 2010 Jun;194(6):1434-42. doi: 10.2214/AJR.10.4404. PMID: 20489081; PMCID: PMC4144010.

[3] G. Ma, D. Han, S. Dang, N. Yu, Q. Yang, C. Yang, C. Jin, Y. Dou, Replacing...

...read more

Same Authors as...