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Purpose Percutaneous radiofrequency ablation (RFA) combined with vertebral augmentation offers effective local tumor control and structural stabilization for symptomatic spinal metastases. Following RFA, early identification of residual or recurrent active disease is critical for definitive treatment. Morphological imaging modalities (MRI and CT) are frequently confounded by post-procedural edema, hemorrhage, and mechanical distortion, making the differentiation between post-ablation necrosis, reactive inflammation, and residual viable tumor challenging. In this study, we highlight a case that demonstrates the clinical utility of serial F-18 FDG PET/CT as a functional imaging modality to monitor metabolic response and guide retreatment strategies in the post-ablation setting.Materials and Methods We retrospectively evaluated the clinical and imaging course of targeted spinal RFA and augmentation in the setting of radiation-refractory metastatic disease. The index patient presented with a symptomatic pathologic fracture of the L3 vertebral body secondary to metastatic gallbladder adenocarcinoma. The baseline pre-procedural F18-FDG PET/CT demonstrated focal metabolic activity localizing to the metastatic lesion. The patient subsequently underwent fluoroscopically guided percutaneous RFA followed immediately by vertebral augmentation. Serial post-procedural 18F-FDG PET/CT scans—acquired as part of the patient’s routine systemic surveillance—were evaluated to monitor the ablation zone for radiotracer uptake and determine local metabolic response.Results Initial post-procedural PET imaging demonstrated borderline radiotracer uptake at the ablation margin, consistent with post-treatment changes. Subsequent short-interval follow-up PET/CT revealed increasing focal metabolic activity along the anterior border of the L3 target zone, successfully identifying local tumor progression or residual active disease prior to the onset of progressive clinical symptoms or gross morphological changes. A contrast enhanced MRI was subsequently obtained, which demonstrated non-specific enhancement in the region of interest. Guided by the functional imaging findings, a targeted repeat RFA and vertebral augmentation was performed at the level. Subsequent follow-up PET scans demonstrated a photopenic ablation zone with no abnormal focal metabolic activity and subsequent and follow up MRI demonstrated no suspicious contrast enhancement pattern, confirming a grossly complete treatment response and establishing durable tumor control.Conclusion Combined RFA and vertebral augmentation is highly effective for achieving local tumor control in radiation-refractory spinal metastases. Crucially, F-18 FDG PET is an indispensable tool in the post-ablation setting. By accurately identifying focally increased metabolic activity independently of post-procedural morphological changes, functional imaging can overcome the inherent limitations of MRI and CT and assist in early diagnosis of residual or recurrent disease. Because oncology patients often undergo serial PET imaging for restaging, evaluating the ablation site provides a critical added benefit without incurring additional healthcare costs or radiation exposure.Disclosures R. Thakkar: None. A. Krajewski: None.