Objective: The purpose of this study was to evaluate whether (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) can be used to assess the therapeutic response of brain abscess.
Methods: A study was conducted on 10 consecutive patients with brain abscess. Magnetic resonance imaging (MRI) with diffuse-weighted imaging (DWI) was performed at 3 and 6 weeks after surgical treatment and intravenous antibiotics therapy and FDG-PET at 6 weeks after treatment. The extent of the abscess, signal changes on MRI, and FDG-PET standardized uptake values were analyzed and correlated with the response to therapy.
Results: Aspiration or craniotomy with excision of the abscess followed by intravenous antibiotics for 6-8 weeks resulted in good recovery with no recurrence. In 10 patients, two had low signal intensity on the DWI; one had no uptake on FDG-PET imaging after 6 weeks antibiotics and discontinued intravenous treatment, but the other patient had diffuse, increased uptake on FDG-PET imaging after 6 weeks antibiotics and underwent an additional 2 weeks of intravenous antibiotics. The remaining eight patients had high signals on the DWI. Four had no uptake on FDG-PET imaging and the treatment period varied from 6 to 8 weeks (mean, 6.75 weeks). Among the other four patients, FDG was accumulated in a diffuse or local area corresponding to a high signal area within the DWI and 2 weeks of intravenous antibiotics was added.
Conclusion: MRI plus FDG-PET improved the accuracy of assessing therapeutic responses to antibiotics treatment of brain abscess and aided in optimizing therapy.
Keywords: 18F-Fluorodeoxyglucose positron emission tomography; Antibiotics; Brain abscess; Diffusion-weighted imaging; Magnetic resonance imaging.