The RSNA exhibit floor may have been awash in X-ray machines and ultrasound systems, but there were some notable exceptions. That high-tech wow factor was apparent in the Philips Healthcare booth, where the first all-digital PET/CT scanner, called Vereos, was introduced.
The standard PET/CT technology features a ring of scintillator crystals coupled with photomultiplier tubes. Philips replaced the vacuum technology with a digital photon-counting technology, improving the volumetric resolution by a factor of two, according to Kirill Shalyaev, PhD, Sr. Director, Product Management, Advanced Molecular Imaging, Philips Healthcare.
“There is no analog signal conversion anywhere in the imaging chain,” he explains, adding that one-to-one coupling of the scintillator crystals and the digital photon-counting detectors drive resolution and eliminates dead time. “[In the standard technology], when light hits the crystal and a photon hits the multiplier, it has to relax before it counts the next photon.”
In addition to improving throughput, enabling visualization of features down to 2.4 mm, and offering the potential to reduce injected dose, the new technology has proven to be a crowd pleaser among one of the modality’s primary referrer groups, medical oncologists. Shalyaev says one nuclear medicine physician said, “We used to be called unclear medicine; now it’s clear.”
Philips also had news in CT with its IQon Spectral CT, the world’s first, says Andy Mack, Sr. Director, CT Product Management, Philips Healthcare. Pending 510 K clearance, the scanner employs a spectral detector that converts low energy (40 KEV) output into images using yttrium-based scintillator crystals, and high-energy output (200 KeV) via the more traditional gadolinium oxysulfide, or GOS, scintillators.
“Because the two different images are acquired simultaneously, they are aligned in time and space,” Mack says. “We can provide the incremental information without adding time or a special mode. A lot of the time, we don’t know until after the exam whether we should have used a different mode.”
In images acquired at lower energy, there is improvement in visualizing contrast enhancement, useful in distinguishing lesions from cysts, and at high energy there is a reduction in metal artifacts. Mack expects that radiologists will read the high-energy grayscale images and review the colored low-energy images as needed.
Also worth a mention is a nifty application found in the Toshiba booth. Developers at TAMS continue to push the envelope when it comes to innovative non-contrast MR protocols. This year, Beverly Plost, Director, MR, described a time-slip technique that uses the patient’s cerebral spinal fluid as a tracer to distinguish Alzheimer’s from hydrocephalus, which might otherwise require a lumbar puncture. That’s patient-centered care.