Radiation Dose Overlay Improves Radiologists' Interpretation of Post-therapy Computed Tomography Imaging for Thoracic...

Radiation therapy dose visualizations created by radiation oncologists are not accessible to diagnostic radiologists; however, access may improve interpretation accuracy and confidence when applied to surveillance imaging of patients with radiation therapy-treated thoracic malignancies.

In a prospective analysis of retrospectively acquired data, 32 imaging series of patients treated with radiation therapy for thoracic malignancies (14 men, 18 women; mean age, 71 years ± SD 10.35 years) were interpreted. One cardiothoracic radiology attending and 1 radiology resident interpreted pretreatment, treatment planning, and posttreatment computed tomography (CT) images in anonymized software sessions first without, then-after a 1 month "washout period"-with access to radiation therapy dose overlays. Readers then labeled treated lesion(s) and treatment effect(s) and recorded their confidence using a Likert scale (1-5) and agreement with yes/no statements. Binary data were analyzed with McNemar's and Fisher's tests, whereas Likert scale data were analyzed with paired 2-sided t tests.

With the addition of radiation dose visualization, the identification of all treated lesions increased from 61% to 81% of CT series (P < .001). This was most pronounced in CT series with multiple treated lesions (15%-54% of CT series, P = .004). Confidence in identification ability also increased from a rating of 4.1 to 4.8 on a scale of 1 to 5 (P < .001), and the desire to access the chart for additional patient information decreased from 3.63 to 3.28 (P = .005).

Access to radiation dose visualization was associated with increased correct identification rate of irradiated lesions and treatment effects, as well as radiologists' confidence in said identifications.