Table 2.
VI-RADS scoring system [26].
| Score | Description |
|---|---|
| T2WI Score Structural category (SC) |
Muscularis propria is T2 hypointense Tumor is T2 intermediate in signal |
| SC 1 | Uninterrupted low signal intensity (SI) line representing the muscularis propria. Lesion < 1 cm Exophytic tumor
|
| SC 2 | Uninterrupted low signal intensity (SI) line representing the muscularis propria Lesion > 1 cm Exophytic tumor with stalk +/− high SI thickened inner layer, when present. Sessile/broad-based tumor with high SI thickened inner layer, when present |
| SC 3 | Lack of category 2 findings with no clear disruption of low SI muscularis propria. Associated presence of
|
| SC 4 | Intermediate SI tumor interrupts low SI line (muscularis propria) |
| SC 5 | Intermediate SI tumor extends into extravesical fat |
| DCE Score Contrast-enhanced category (CE) |
Tumor and inner layer enhance early Muscle should not enhance early |
| CE 1 | No early enhancement of muscularis propria |
| CE 2 | No early enhancement of muscularis propria with early enhancement of inner layer |
| CE 3 | Lack of category 2 findings with no clear disruption of muscularis propria |
| CE 4 | Early enhancing tumor extends into muscularis propria |
| CE 5 | Early enhancing tumor extends to entire bladder wall and to extravesical fat |
| DWI/ADC score Diffusion weighted category (DW) |
Tumor is hyperintense on DWI, hypointense on ADC Muscularis propria is intermediate SI on DWI Stalk and inner layer are low SI on DWI |
| DW 1 | Intact intermediate SI muscularis propria on DWI Lesion < 1 cm |
| DW 2 | Intact intermediate SI muscularis propria on DWI Lesion > 1 cm |
| DW 3 | Lack of category 2 findings with no clear disruption of muscularis propria |
| DW 4 | Tumor (high SI on DWI/low SI on ADC) extends into muscularis propria |
| DW 5 | Tumor (high SI on DWI/low SI on ADC) extends to entire bladder wall and extravesical fat |
| Final Score | T2WI helpful especially for VI-RADS 1-3 DWI and DCE are dominant sequences for risk estimate, especially for VI-RADS 4-5 |
| VI-RADS 1 | Muscle invasion highly unlikely SC 1, CE 1, and DW 1 |
| VI-RADS 2 | Muscle invasion unlikely SC 2 + CE 2 and DW 2 SC 3 + CE 2 and DW 2 |
| VI-RADS 3 | Muscle invasion equivocal SC 3 + CE 3 and/or DW 3 (or below) |
| VI-RADS 4 | Muscle invasion likely SC 4 + CE 4 and/or DW 4 (or below) SC 5 + CE 4 and/or DW 4 (or below) |
| VI-RADS 5 | SC 4 + CE 5 and/or DW 5 SC 5 + CE 5 and/or DW 5 |