ProUroCare Medical, Inc., of Minneapolis, Minn., has filed a de novo application with the FDA seeking marketing clearance for its prostate mechanical imaging (PMI) device (ProUroScan). This will allow the agency to review and potentially classify such systems as Class II devices subject to special controls.
The company’s filing asks the FDA to define mechanical imaging systems as devices intended to produce an elastic image of the prostate as an aid in documenting abnormalities of the prostate that are initially identified by digital rectal examination (DRE).
ProUroScan uses a transrectal probe with pressure sensor arrays and a motion tracking system. The system provides real-time elasticity images of the prostate, the company said. The device can detect and pinpoint nodules because they differ in hardness from surrounding healthy tissue. In a study published in Urology (2008;71:425-429), researchers showed that PMI results correlated strongly with DRE findings.
The investigators tested PMI and DRE results for correlation against a transrectal ultrasound of the prostate guided biopsy for a subgroup of 21 men with elevated PSA levels. Of 13 patients with biopsy-confirmed malignant nodules, PMI identified 10 of the nodules and DRE identified six. PMI findings were consistent with all eight biopsy-negative cases. DRE resulted in one false-positive result in the eight biopsy-negative cases.
“The PMI device has the potential to document prostate nodularity by producing 3D images of the gland and its internal structures based on their respective hardness,” the researchers concluded.