Table 1 Minimal technical requirements for multiparametric prostate MRI according to the PI-RADS v. 2.1 guidelines
From: Multiparametric prostate MRI quality assessment using a semi-automated PI-QUAL software program
Axial T2-weighted imaging (T2-WI) | Diffusion-weighted imaging (DWI) | Dynamic contrast-enhanced (DCE) | |
|---|---|---|---|
Imaging planes | The same used for DWI and DCE | The same used for T2-WI and DCE | The same used for T2-WI and DWI |
Slice thickness | 3 mm, no gap | ≤ 4 mm, no gap | 3 mm, no gap |
Field of view | 12–20 cm (to encompass the entire prostate gland and seminal vesicles) | 16–22 cm | 12–20 cm (to encompass the entire prostate gland and seminal vesicles) |
In-plane resolution | ≤ 0.7 mm (phase) × ≤ 0.4 mm (frequency) | ≤ 2.5 mm (phase and frequency) | ≤ 2 mm (phase and frequency) |
Specific recommendations | |||
T2-WI acquisition | Axial plane: either straight axial to the patient or in an oblique axial plane matching the long axis of the prostate. At least one additional orthogonal plane (sagittal and/or coronal). Three-dimensional axial as an adjunct to two-dimensional acquisitions | – | – |
Low b value | – | 50–100 s/mm2 | – |
Intermediate b value | – | 800–1,000 s/mm2 | – |
High b value | – | Dedicated (≥ 1,400 s/mm2) Synthesised (from other b values) | – |
Temporal resolution | – | – | ≤ 15 s |
Total observation time | – | – | > 2 min |
Dose of Gd-based contrast agent | – | – | 0.1 mmol/kg |
Injection rate | – | – | 2–3 cc/s |
Fat suppression and/or subtraction | – | – | Recommended |