SRS MR Distortion Phantom

Characterize Geometric Accuracy for MR Use in Treatment Planning
The SRS MR Distortion Phantom is useful for verifying image fusion and deformable image registration algorithms used in various treatment planning systems. The tissue equivalent, anthropomorphic design closely matches clinical imaging scenarios.

Tissue Equivalent, Anthropomorphic Head
The skull is made from a plastic-based trabecular bone substitute, and the interstitial and surrounding soft tissues are made from a proprietary signal-generating water-based polymer. The entire phantom is encased in a clear plastic shell to protect gel from desiccation. Specially designed pads allow fixation with any stereotactic frame or mounting devices for end-to-end
testing. The phantom is also suitable for frameless SRS QA.

Finely Detailed Inter-Cranial 3D Design
The entire inter-cranial portion of the skull volume is filled with an orthogonal 3D grid of 2.5 mm diameter cross-like shaped rods spaced 10 mm (I-S), 10.5 mm (AP), and 11 mm (L-R). Extra material added in the grid intersections increases grid signal. Five extended axis-rods intersect at the reference origin of the grid. The end of each extended axis is fitted with CT/MR markers allowing for accurate positioning with lasers and co-registration of CT and MR image sets.

The phantom contains air voids on both sides that replicate ear canals. These voids are utilized to assess common distortions encountered in clinical settings.

The SRS MR Distortion Phantom can be imaged using X-ray, CT and MR. It images well with all MRI sequences tested to date, including T1 weighted, T2 weighted, 3D Time of Flight, MPRAGE and CISS.