Diffusion-Imaging (DWI)
This post was updated June 2025.
Of all the sequences performed during a full-body MRI, diffusion-weighted imaging is arguably the most critical for the detection of cancer. However, diffusion-imaging suffers challenges at higher magnetic strengths resulting in increasing distortion of full-body application. In other words, full-body DWI is more difficult to implement on 3T platforms compared to 1.5T. As a result, many 3T providers omit diffusion as the resulting image quality adds no clinical value. Click here to read more about the importance and challenges of DWI.
Below is a table that compares 1.5T and 3T MRI platforms and the use or inclusion of diffusion-weighted imaging.
Diffusion-weighted Imaging (DWI)
| Location | Magnet Strength | Scan Time | DWI Performed | True Full-body DWI | Comment |
|---|---|---|---|---|---|
| Adelaide MRI | 1.5T | 40 - 60 minutes | Likely | No | Not a true full-body MRI |
| Aspect Radiology | 3T | 45 minutes | No | N/A | |
| Brisbane Radiology | 3T | 45 - 60 minutes | Yes* | Yes* | *DWI without clinical value |
| CRT Imaging | 3T | 45 minutes | Yes | No | Segmented DWI |
| Ezra | 3T | 60 minutes | No | N/A | |
| HealthScreen | 1.5T | Unknown | Likely | Unknown | |
| Mermaid Beach Radiology | 3T | 60+ - 100 minutes, depending on package | Yes | Yes | Recent price increase with base package now at $3750 for 60-75 minute scan; or $4250 with addition of quantitative imaging. |
| Panorama Radiology Specialists | 3T | Over 3 days | Likely | No | Not a true full-body MRI |
| Prenuvo (USA) | 1.5T | >50 minutes | Yes | Yes | |
| Prenuvo (AUS) | 1.5T Open MRI | >50 minutes | Yes | Yes | Sensitivity is less than USA Prenuvo. Advertised at 10mm+ |
Conclusion
Looking at all the providers, only two are known to include true full-body diffusion in their imaging - Prenuvo (USA / AUS) and Mermaid Beach Radiology (3T). Full-body diffusion is the “cancer money shot”, and is considered to be the most important acquisition in cancer imaging on MRI.
We appreciate that geographical location, may for most individuals, be the ultimate decider between these two.
However, the Whole Body MRI Pty Ltd partner Mermaid Beach Radiology has a the advantage of utilising a 3T platform, enabling faster acquisition of more high-resolution data compared to Prenuvo’s 1.5T closed (USA) & open systems (AUS).
This vast data differential is further exacerbated by differing scan times - 50 minutes on the slower 1.5T compared to 100 minutes on the faster 3T. In full-body MRI, less is less.
When factoring value for money, Mermaid Beach Radiology comes out significantly cheaper as a once-off payment ($3750 versus approximately $4000 AUD for USA / $3500 for AUS location), but also as a function of scan time, included technology and patient experience.