Table 2.
Overview of recommended MR sequences and commercial online availability for clinical breast cancer treatment on hybrid machines.
| Type of MR sequence | Advantages (+) and disadvantages (-) | Availability on Unity (Elekta AB) | Availability on MRIdian® (ViewRay®) |
|---|---|---|---|
| Postoperative | |||
| T1-weighted with fat suppression (9, 20, 34) | + Differentiation between glandular breast tissue and seroma | Not available* | Not available |
| T1-weighted without fat suppression (9, 20, 34) | + Best visualization of surgical clips | 3D T1-weighted FFE | 3D T2/T1-weighted TRUFI |
| T2-weighted with or without fat suppression (17, 19, 21, 22, 24) | + Visualization of lumpectomy cavity and seromaramya + Differentiation between glandular breast tissue and seroma | 3D T2-weighted TSE without fat suppression* | 3D T2/T1-weighted TRUFI |
| DWI (35) | + Differentiation between malignant and benign tissue in case of irradical resection ramya – Susceptible to geometric distortions | Not available* | Not available* |
| Preoperative | |||
| T1-weighted contrast-enhanced with fat suppression (35–38) | + Visualization of tumour and tumour spiculae ramya – Injection of and irradiation with contrast agent | No standard contrast injection available | No standard contrast injection available |
| T2-weighted with or without fat suppression (35) | + Differentiation between tumour and post-biopsy changes | 3D T2 TSE without fat suppression* | 3D T2/T1-weighted TRUFI |
| DWI (35) | + Differentiation between malignant and benign tissue ramya – Susceptible to geometric distortions | Not available* | Not available* |
TSE, turbo spin echo (fast spin echo); FFE, fast field echo (spoiled gradient echo); TRUFI, true fast imaging with steady state precession (balanced steady state free precession).
*
Not available in online treatment setting. Acquiring DWI and MR sequences with fat suppression is possible offline—outside online treatment setting mode.
This table does not provide an exhaustive overview of all imaging possibilities but only refers to MR sequences mentioned in this article and currently commercially available imaging options.