At the Society of Nuclear Medicine and Molecular Imaging's 2026 Annual Meeting in Los Angeles, researchers unveiled a breakthrough that could transform how doctors treat one of the most difficult lung diseases to diagnose: a new SPECT/CT imaging technique that finally reveals what standard scans cannot—whether a patient's lungs are inflamed or scarred. This distinction matters enormously, because the wrong treatment can cause serious harm.
Interstitial lung disease encompasses more than 200 different conditions and affects approximately 650,000 people across the United States, claiming an estimated 25,000 to 30,000 lives annually. The disease progresses in stages, and doctors have long struggled to pinpoint whether a patient's lungs are in the inflammatory phase—when anti-inflammatory drugs can help—or the fibrotic phase, when scar tissue has already formed. Current imaging can show structural damage, but it cannot reliably detect inflammation without invasive procedures.
"While current imaging techniques can provide a structural view of fibrosis in the lungs, there is no reliable, non-invasive way to identify inflammation," said Druin Burch, a consultant physician at John Radcliffe Hospital in Oxford, United Kingdom, who worked on the study. During the COVID-19 pandemic, researchers observed this challenge firsthand: all infected patients initially had inflammation, and anti-inflammatory treatments proved highly effective. But outside that uniform scenario, identifying which patients would actually benefit from these drugs has remained elusive.
The new approach uses a molecular imaging agent called ⁹⁹ᵐTc-maraciclatide, which visualizes the formation of new blood vessels—a hallmark sign of inflammatory disease. In a pilot study, researchers scanned 15 participants: five with idiopathic pulmonary fibrosis, five with fibrotic hypersensitivity pneumonitis, and five healthy controls. Nuclear medicine physicians and thoracic radiologists analyzed the images using standardized measures including radiological patterns, standardized uptake values, and target-to-background ratios.
The results were striking. Healthy controls showed minimal tracer uptake in their lungs, while both groups of patients with interstitial lung disease demonstrated distinct, measurable uptake. The target-to-background ratio—a key indicator of inflammation—was numerically higher in the diseased lung tissue compared to healthy tissue. This clear distinction means the scan can reliably separate inflammation from fibrosis, allowing doctors to choose treatments wisely.
"Being able to differentiate the fibrotic and inflammation stages of ILD is not just beneficial to inform treatment decisions, but also for the development of new therapies," Burch noted. The ability to identify which patients have active inflammation could unlock access to a wide range of anti-inflammatory drugs that currently sit on the shelf, deemed too risky without a reliable way to confirm they would help.
Before patients can access this imaging in hospitals and clinics, a Phase 3 study in a larger population is required. The encouraging news: ⁹⁹ᵐTc-maraciclatide has already received FDA Fast Track designation for imaging interstitial lung disease, a pathway that accelerates development of promising treatments. If a Phase 3 trial begins soon, this tool could reach patients within approximately two years—potentially opening new doors for hundreds of thousands of people searching for the right treatment.