Focal Vascular Photopenia as a Metabolic Signature of Pulmonary Embolism on AI-Enhanced 18 F-FDG PET/CT.

Artificial intelligence (AI)-enhanced reconstruction of 18 F-FDG PET/CT may reveal important metabolic patterns barely visible on standard reconstructions. In this case, AI-enhanced reconstruction demonstrated sharply demarcated photopenia with discrete surrounding foci of increased uptake corresponding to verified pulmonary embolisms in the right pulmonary artery. Traditional PET systems and reconstructions lack the ability to identify such subtle 18 F-FDG patterns. The improved image resolution and the AI‑enhanced reconstruction highlight the ability of modern PET/CT systems to disclose clinically relevant metabolic abnormalities-including "cold spots"-that may otherwise be overlooked. Written consent from the patient has been obtained.