PROSTATE CANCER SCREENING, BIOPSY AND TREATMENT REIMAGINED
We are creating an office-based, high resolution MRI, and MR compatible biopsy and treatment devices, to eliminate the inefficiencies, complexities and costs of using prostate-specific antigen (PSA) with multi-parametric MRI and fusion.
Promaxo's patented MR technology takes advantage of proprietary ultra-fast and strong gradients and pre-polarization fields which can be switched on rapidly without causing bio-effects (e.g., nerve stimulation). Our prototype MRI systems have demonstrated rise- and fall-times about one-hundred times faster than conventional MRI. These rapid and strong gradients (about 10 T/m) permit collection of millions of points in k-space in tens of seconds, yielding images with spatial resolution of 30 microns, comparable to histology.
Rapid acquisition is more effective at collecting data earlier in the T2* relaxation time, thereby increasing signal. Based on classical formulas that take into account signal-to-noise ratio (SNR), we estimate that we could collect slices every 250µm, with 30µm resolution throughout the prostate in a few minutes. Collection of similar image sets with conventional MRI would take hours.
High gradients reduce sensitivity to artifacts (e.g., from metals or hemorrhage). The fast pulse sequences reduce artifacts introduced by patient movement, metallic implants, system engineering limitations, and field homogeneity. Gradient outputs are monitored in real-time to reduce artifacts due to eddy currents and amplifier non-linearity. The single-sided MRI concept has been adopted for the prostate by including novel RF coil geometries that obviate endorectal components.