Vesical Imaging-Reporting and Data System (VI-RADS)

The Vesical Imaging–Reporting and Data System (VI-RADS) is a structured reporting scheme for multiparametric bladder MRI in the evaluation of suspected bladder cancer. A systematic approach to bladder lesion based on multiparametric MRI (mpMRI) was proposed by the European Association of Urology in 2018 ¹.

Assessment categories

A combination of imaging findings - T2WI (SC-category), DWI (DW-category), and dynamic contrast enhancement (CE-category) - predicts the probability of cancer that is clinically significant, which is defined as the presence of any of the following. 

Each lesion is assigned a score from 1 to 5 indicating the likelihood of clinically significant cancer:

VI-RADS 1

• muscle invasion is highly unlikely
• SC, CE and DW category 1

VI-RADS 2

• muscle invasion is unlikely to be present
• SC category 2-3
• CE and/or DW category 2

VI-RADS 3

• presence of muscle invasion is equivocal
• SC, CE and DW category 3

VI-RADS 4

• muscle invasion is likely
• SC category 3-5
• DW and/or CE category 4

VI-RADS 5

• invasion of muscle and beyond the bladder is very likely
• SC category 4-5
• DW and/or CE category 5

Radiographic features

Assessment for T2-WI with structural category (SC)

SC1-category

• uninterrupted low signal line representing the integrity of muscularis propria
• lesion <1 cm
• exophytic tumor with stalk and/or high signal thickened inner layer

SC2-category

• uninterrupted low signal line representing the integrity of muscularis propria
• lesion >1 cm
• exophytic tumor with stalk and/or high signal thickened inner layer or sessile/broad-based tumor with high signal thickened inner layer

SC3-category

• lack of category 2 findings with associated presence of an exophytic tumor without stalk
  or
• sessile/broad-based tumor without high signal thickened inner layer but with no clear disruption of low signal muscularis propria

SC4-category

• interruption of low signal line suggesting extension of the intermediate signal tumor tissue to muscularis propria

SC5-category

• extension of intermediate signal tumor to extravesical fat, representing the invasion of the entire bladder wall and extravesical tissues

Assessment for DCE with contrast-enhanced category (CE)

CE1-category

• no early enhancement of the muscularis propria
• lesions corresponding to SC1 findings

CE2-category

• no early enhancement of muscularis propria with early enhancement of inner layer
• lesions corresponding to SC2 findings

CE3-category

• lack of category 2 findings but with no clear disruption of low signal muscularis propria
• lesions corresponding to SC3 findings

CE4-category

• tumor early enhancement extends focally to muscularis propria

CE5-category

• tumor early enhancement extends to the entire bladder wall and to extravesical fat

Assessment for DWI/ADC with DW category (DW)

DW1-category

• muscularis propria with intermediate continuous signal on DWI
• lesion <1 cm
• hyperintense on DWI and hypointense on ADC, with or without stalk and/ or low signal thickened inner layer on DWI

DW2-category

• muscularis propria with continuous intermediate signal on DWI
• lesion >1 cm
• hyperintense on DWI and hypointense on ADC, with low signal stalk and/or low signal thickened inner layer on DWI
  or
• broad-based/sessile tumor with low/intermediate signal thickened inner layer on DWI

DW3-category

• lack of category 2 findings (lesions corresponding to T2 category 3 findings) but with no clear disruption of low signal muscularis propria

DW4-category

• high signal tumor on DWI and low signal tumor on ADC extending focally to muscularis propria

DW5-category

• high signal tumor on DWI and low signal tumor on ADC extending to the entire bladder wall and extravesical fat

See also

• RADS (Reporting and Data Systems)