Digital Tomosynthesis for Evaluating Metastatic Lung Nodules: Nodule Visibility, Learning Curves, and Reading Times

Abstract

ObjectiveTo evaluate nodule visibility, learning curves, and reading times for digital tomosynthesis (DT).Materials and MethodsWe included 80 patients who underwent computed tomography (CT) and DT before pulmonary metastasectomy. One experienced chest radiologist annotated all visible nodules on thin-section CT scans using computer-aided detection software. Two radiologists used CT as the reference standard and retrospectively graded the visibility of nodules on DT. Nodule detection performance was evaluated in four sessions of 20 cases each by six readers. After each session, readers were unblinded to the DT images by revealing the true-positive markings and were instructed to self-analyze their own misreads. Receiver-operating-characteristic curves were determined.ResultsAmong 414 nodules on CT, 53.3% (221/414) were visible on DT. The main reason for not seeing a nodule on DT was small size (93.3%, ≤ 5 mm). DT revealed a substantial number of malignant nodules (84.1%, 143/170). The proportion of malignant nodules among visible nodules on DT was significantly higher (64.7%, 143/221) than that on CT (41.1%, 170/414) (p < 0.001). Area under the curve (AUC) values at the initial session were > 0.8, and the average detection rate for malignant nodules was 85% (210/246). The inter-session analysis of the AUC showed no significant differences among the readers, and the detection rate for malignant nodules did not differ across sessions. A slight improvement in reading times was observed.ConclusionMost malignant nodules > 5 mm were visible on DT. As nodule detection performance was high from the initial session, DT may be readily applicable for radiology residents and board-certified radiologists.

Detection and Characterization of Solid Pulmonary Nodules at Digital Chest Tomosynthesis: Data from a Cohort of the Pilot Swedish Cardiopulmonary Bioimage Study

“…Observers worked at a department of thoracic radiology, reading DTS as part of daily clinical practice, a factor that limits the generalization of the results to the general in the reference truth. Retrospectively, 95% of solid nodules included in our study were considered visible at DTS, which is higher than the previously reported 53%-71% (19) and 53% (20), though the former applied a strict requirement of definitely visible and the latter included small nodules (43% of nodules were 3 mm).…”

“…Previous studies (9,19,20) reported detection rates between 56% and 70% by using DTS for CT-proven nodules, and these results were mainly in patients who were initially admitted for CT because they were suspected of having disease. DTS was suggested (3,6) as a low-dose alternative to CT for lung cancer screening; however, to our knowledge, no previous studies investigated DTS in imaging incidental nodules detected in a population cohort.…”

“…Inability to detect or correctly classify nodules at DTS can be affected by multiple factors, where the limited depth resolution of DTS is considered as one of the more important limitations of the modality (20). Another factor is motion artifacts, and this study involved cases with suboptimal image quality, deliberately not excluded to be more representative of the clinical situation.…”

Digital chest tomosynthesis: the 2017 updated review of an emerging application

“…Practically any cancer can spread to the lungs, but the neoplasms commonly do include bladder, colon, breast, prostate, sarcoma, Wilms tumour, and neuroblastoma. DCT could be an ideal imaging tool for this problem; alternating CT scan and DCT interval examinations may become an optimal solution to reduce costs and radiation risk (36). DCT could be quickly introduced in the routine diagnostic workflow as a casesolving technique in oncologic patients with suspected or ambiguous pulmonary lesions on radiography (37).…”

Detection of Acetabular and Proximal Femoral Radiographic Abnormalities Showed by Hip Digital Tomosynthesis in Special Functional Position Compared with Conventional Radiography

“…Therefore, hip digital tomosynthesis in special functional position (DT -SFP) has been designed for investigation of hip joint. DT is a newly digitalized sectional imaging technology developed in recent years and has greater advantages over conventional radiography in the imaging quality and diagnostic accuracy in showing some complex anatomical structures (9,10). Thus, the application of DT for skeletal imaging has gradually attracted more and more attention in recent years (11)(12)(13).…”