A two-compartment phosphate-doped gel phantom for localized spectroscopy.

Acrylamide gel loaded with phosphate has been used in two compartment phantoms designed to assess localized spectroscopy techniques. A chemical shift difference of 2.3 ppm was produced by changing the pH from 6 to 8.9. The 31P relaxation times were modified by doping the gels with paramagnetic ions. For a T1 of approximately 1 sec nickel doping gave a T2 of approximately 110 msec and manganese doping gave a T2 of approximately 8 msec. Gel phantoms are more robust than their liquid equivalent and are not prone to leakage. The construction of small compartments with very thin walls is possible, making this type of phantom suitable for small bore imaging/spectroscopy systems.