SpotLight/SpotLight Duo with Low Dose Lung Cancer Screening Option

The SpotLight/SpotLight Duo with Low Dose Lung Cancer Screening Option is a computed tomography X-ray system that produces cross-sectional body images by reconstructing X-ray transmission data. The device is indicated for cardiovascular and thoracic imaging, and includes a new Low Dose CT option for lung cancer screening in medium and large patients following established protocols from the American College of Radiology (ACR) and American Association of Physicists in Medicine (AAPM).

The proposed device is technologically identical to the predicate (K230370) with no functional, performance, feature, or design changes except for added low-dose lung cancer screening protocols. Both use the same detector technology, X-ray sources (Varex MCS 2093 tubes), reconstruction algorithms (modified FDK cone beam), and system specifications. The key difference is that DLIR and ASIR-CV algorithms are incompatible with the new LD LCS option.

Bench testing evaluated image quality using standard phantoms and metrics: CT number accuracy, uniformity, noise power spectrum (NPS), modulation transfer function (MTF), contrast-to-noise ratio (CNR), and nodule sizing. AAPM CTDI dose value requirements for low-dose lung cancer screening were applied. Clinical evaluation used board-certified radiologist image quality assessment on 14 patient cases representing medium and large patient sizes per AAPM guidelines.

Substantial equivalence is established because the LD LCS option requires no hardware changes and only minor software modifications for protocol compatibility. Bench testing demonstrated all image quality metrics (uniformity, NPS, resolution, CNR, nodule detection) are maintained and comparable to the predicate device. Clinical evaluation of 14 cases confirmed diagnostic image quality with successful detection of small nodules down to 2mm. The proposed protocols comply with AAPM CTDI dose specifications for low-dose screening without introducing new safety or effectiveness concerns relative to the predicate device's established performance profile.