Dedicated Breast Computed Tomography With a Photon-Counting Detector

Abstract

OBJECTIVES: The purpose of this work is to present the data obtained from the first clinical in vivo application of a new dedicated spiral breast computed tomography (B-CT) equipped with a photon-counting detector. MATERIALS AND METHODS: The institutional review board approved this retrospective study. Twelve women referred for breast cancer screening were included and underwent bilateral spiral B-CT acquired in prone position. Additional sonography was performed in case of dense breast tissue or any B-CT findings. In 3 women, previous mammography was available for comparison. Soft tissue (ST) and high-resolution (HR) images were reconstructed. Two independent radiologists performed separately the readout for subjective image quality and for imaging findings detection. Objective image quality evaluation was performed in consensus and included spatial resolution, contrast resolution, signal-to-noise ratio (SNR), and contrast-to-noise ratio. All women were asked to report about positioning comfort and overall comfort during data acquisition. RESULTS: The major pectoral muscle was included in 15 breast CT scans (62.5%); glandular component was partially missing in 2 (8.3%) of the 24 scanned breasts. A thin "ring artifact" was present in all scans but had no influence on image interpretations; no other artifacts were present. Subjective image quality assessment showed excellent agreement between the 2 readers (= 1). Three masses were depicted in B-CT and were confirmed as simple cysts in sonography. Additional 5 simple cysts and 2 solid benign lesions were identified only in sonography. A total of 12 calcifications were depicted with a median size of 1.1 mm (interquartile range, 0.7-1.7 mm) on HR and 1.4 mm (interquartile range, 1.1-1.8 mm) on ST images. Median SNRgl, SNRfat, and contrast-to-noise ratio were significantly higher in ST than in HR reconstructions (each, P < 0.001). A mild discomfort due to positioning of the rib cage on the table was reported by 2 women (16.7%); otherwise, no discomfort was reported. CONCLUSIONS: The new dedicated B-CT equipped with a photon-counting detector provides high-quality images with potential for screening of breast cancer along with minor patient discomfort.

Quantitative characterization of breast tissues with dedicated CT imaging

“…Among them, tomosynthesis is often used in clinical practice as a second-level examination (Sechopoulos 2013a, Sechopoulos 2013b. Breast Computed Tomography (BCT) instead, although not widely used clinically, is arising an increasing interest and several research groups worldwide performed clinical trials (Lindfors 2008, O'Connell 2010, Kalender 2017, Berger 2019. A few clinical systems are available commercially: the Friedrich-Alexander University of Erlangen-Nürnberg A c c e p t e d M a n u s c r i p t (Germany) § and the Rochester Medical Center (USA) promoted startup companies to manufacture and commercialize their prototypes.…”

Recent advances in X-ray imaging of breast tissue: From two- to three-dimensional imaging

“…Thereby, the best example is the german company AB-CT -Advanced Breast-CT which developed a clinical device called nu:view [65] that is installedamong othersat the University Hospital of Zurich. The first results of clinical in vivo BCT imaging have just recently been published by Berger et al showing high image quality, low radiation dose (between 4.4 and 5.7 mGy obtained by Monte-Carlo simulations) and improved patient comfort [66]. In Fig.…”

“…One of the major discussed issues remaining is the applied radiation dose which should be as low as reasonably achievable (ALARA principle). The introduction of the photon-counting detector technology with several benefits compared to conventionally used flat panel detectors [62] with high quantum efficiencies helps to further decrease the MGD in BCT [63][64][65][66]. In 2011, Kalender et al introduced a high resolution spiral BCT with a very low MGD (below 5 mGy) [63] and short acquisition times (below ten seconds) [63,64].…”

Dose and spatial resolution analysis of grating-based phase-contrast mammography using an inverse Compton x-ray source

“…They recently presented the first results of clinical in vivo imaging. 31 As already mentioned, the attenuation-based signal suffers from low soft tissue contrast that should be improved by phase-contrast imaging. But for this application, the applied MGD remains a challenging topic that needs to be investigated and reduced for tomography applications of the breast as-for grating-based phasecontrast imaging-it is above the maximum allowable clinical MGD and only investigated with small but representative tissue sections of a mastectomy specimen.…”