Dual-layer spectral CT fusion imaging for lung biopsies: more accurate targets, diagnostic samplings, and biomarker information?

Abstract

The increasingly widespread use of computed tomography (CT) has increased the number of detected lung lesions, which are then subjected to needle biopsy to obtain histopathological diagnosis. Obtaining high-quality biopsy specimens is fundamental for diagnosis and biomolecular characterisation that guide therapy decision-making. In order to obtain samples with high diagnostic potential, fusion imaging techniques, such as fusion between positron emission tomography and CT, have been introduced to target the biopsy where there more viable neoplastic cells can be sampled. Nowadays, dual-layer spectral CT represents a novel technology enabling an increased tissue characterisation. In particular, Z-effective images, i.e., colour-coded images based on the effective atomic number of tissue components, provide a higher level of discrimination than usual imaged based on x-ray attenuation in Hounsfield units and offer the potential of a better tissue characterisation. Our hypothesis is based on the future use of data provided by spectral CT, in particular by Z-effective images, as a guide for appropriate biopsy sampling for histopathological and biomolecular characterisation in the era of patient tailored-therapy.

Dual-Layer Spectral CT as Innovative Imaging Guidance in Lung Biopsies: Could Color-Coded Z-Effective Images Allow More Diagnostic Samplings and Biomarkers Information?

“…Before starting this study, Fontana et al conducted a thorough evaluation of various reconstruction techniques and imaging combinations. This investigation led to the conclusion that the most accurate results were obtained through the use of combined Zeff map/CBCT fusion imaging [41].…”

Transcatheter Aortic Valve Implantation (TAVI) Planning with Dual-Layer Spectral CT Using Virtual Monoenergetic Image (VMI) Reconstructions and 20 mL of Contrast Media

“…From a single study, it is possible to decide retrospectively to enhance contrast by employing VMI reconstructions, create a virtual non-contrast image [18] to minimize patient radiation exposure, or investigate tissue composition through the utilization of Z effective images [19,20]. With dual-layer technology, there is no need to schedule a separate examination for a specific clinical question.…”

Computed-Tomography-Guided Lung Biopsy: A Practice-Oriented Document on Techniques and Principles and a Review of the Literature

“…Another option is to register intraprocedural CBCT images to dual-layer spectral CT images. Spectral CT is a novel technology that enables better tissue characterization, specifically using Z -effective images based on the effective atomic number of tissue components, potentially us allowing to detect more-viable neoplastic tissue areas to be biopsied [ 135 ]. Information on the effective atomic number of the tissue is obtained from the spectral decomposition in the form of photoelectric and Compton scattering data [ 136 ].…”