Interrater Agreement of BT-RADS for Evaluation of Follow-up MRI in Patients with Treated Primary Brain Tumor

Boxplot graph showing time (in months) from the oldest MRI to the prior MRI used by readers to assign a BT-RADS score. The maximum and minimum values are represented at either end of the whiskers. The box represents the interquartile range (25th percentile to the 75th percentile), with the median value represented by the thick horizontal black line within the box. Outliers are shown away from the whiskers and box by the symbol (○).

Violin graph showing boxplot inside an attenuation plot. The width of the attenuation plot at any region corresponds to the frequency of the data points at that region. For the boxplot, the maximum and minimum values are represented at either end of the whiskers. The box represents the interquartile range (25th percentile to the 75th percentile), with the median value represented by a thick horizontal black line either within the box or at either end of the box. The mean value is represented by the black triangle (▴). Outliers are shown away from the whiskers and box by small black dots (●). On a scale of 1–5 (with 1 = very little, and 5 = great deal), all 6 readers rated how much perfusion contributed to their interpretation of scan and assignment of BT-RADS score.

Violin graph showing boxplot inside an attenuation plot. The width of the attenuation plot at any region corresponds to the frequency of the data points at that region. For the boxplot, the maximum and minimum values are represented at either end of the whiskers. The box represents the interquartile range (25th percentile to the 75th percentile), with the median value represented by a thick horizontal black line either within the box or at either end of the box. The mean value is represented by the black triangle (▴). Outliers are shown away from the whiskers and box by small black dots (●). On a scale of 1–5 (with 1 = not sure at all, and 5 = absolutely sure), all 6 readers rated their level of confidence for the BT-RADS score they assigned to each case. Neuroradiologists (Faculty_1, Faculty _2, Faculty _3, and Faculty _4); Radiology residents (Resident_1 and Resident_2).

Imaging from a patient with agreement among all readers. A 48-year-old man with IDH–wild-type glioblastoma. FLAIR (A) and T1 postcontrast (B) imaging 18 months after surgery showing abnormal FLAIR and enhancing treated tumor in the left temporal lobe. FLAIR (C) and T1 postcontrast (D) 2 months later showing marked increase in the size of abnormal masslike FLAIR and enhancement (white arrows) with >25% increase in cross-sectional area. All readers gave the study a score of BT-RADS 4.