Advanced respiratory imaging company 4D Medical has obtained U.S. Food and Drug Administration (FDA) 510(k) clearance for CT:VQ, a non-contrast, ventilation-perfusion (VQ) imaging solution.

4D Medical said CT:VQ is the world’s first technology of its kind. In parallel, the U.S. Centers for Medicare & Medicaid Services (CMS) confirmed reimbursement for CT:VQ under Category III CPT codes—the payment adds to existing reimbursement for the underlying chest CT.

CT:VQ converts standard, non-contrast chest CTs into quantitative, lobar ventilation (V) and perfusion (Q) maps. It’s delivered as software-as-a-service (SaaS) and integrates with routine radiology workflows (DICOM-based, PACS imaging), leveraging the about 14,500 CT scanners in the U.S. installed base.

The company hopes CT:VQ can bring functional lung imaging to sites without the capacity for nuclear medicine. It transforms routine, non-contrast chest CT into a reimbursable V/Q study, removing the necessity of new hardware. The appointment is completed in one visit without injections.

After that, radiologists receive high-res, quantitative V/Q maps directly in PACS, allowing pulmonologists to get information for PE workups, CTEPH assessment, COPD phenotyping, BLVR planning, and ongoing monitoring.

Clinical validation for the technology included quantitative performance testing against SPECT, expert reader studies, and real-world cases in multiple lung conditions. Early U.S. clinical partners were Stanford University and Brooke Army Medical Center—the latter revealed initial findings at this year’s American Thoracic Society meeting.

“CT:VQ gives clinicians all the contrast—and none of the injections,” said Andreas Fouras, Ph.D., founder and CEO of 4DMedical. “With FDA clearance and Medicare payment in place, any hospital with a CT scanner can turn a routine chest CT into a high–resolution ventilation–perfusion study in minutes, without new hardware or workflow complexity. The word ‘breakthrough’ is overused, but we believe the unprecedented capabilities of CT:VQ qualify for that description.”