Impact of MR-Based Attenuation Correction on Neurologic PET Studies
| Autor: | Jing Qi, Jonathan McConathy, Richard Laforest, Yi Su, Tammie L.S. Benzinger, Akash Sharma, Agus Priatna, Brian B. Rubin |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Amyloid
medicine.medical_specialty business.industry Attenuation Brain Magnetic Resonance Imaging Multimodal Imaging Article 030218 nuclear medicine & medical imaging Food and drug administration Radiation exposure 03 medical and health sciences 0302 clinical medicine Activity measurements Positron-Emission Tomography Image Processing Computer-Assisted medicine Prescribing information Humans Radiology Nuclear Medicine and imaging Radiology Nuclear medicine business Correction for attenuation 030217 neurology & neurosurgery |
| Zdroj: | Journal of Nuclear Medicine. 57:913-917 |
| ISSN: | 2159-662X 0161-5505 |
| Popis: | Hybrid PET and MR scanners have become a reality in recent years, with the benefits of reduced radiation exposure, reduction of imaging time, and potential advantages in quantification. Appropriate attenuation correction remains a challenge. Biases in PET activity measurements were demonstrated using the current MR-based attenuation-correction technique. We aimed to investigate the impact of using a standard MR-based attenuation correction technique on the clinical and research utility of a PET/MR hybrid scanner for amyloid imaging. Methods: Florbetapir scans were obtained for 40 participants on a hybrid scanner with simultaneous MR acquisition. PET images were reconstructed using both MR- and CT-derived attenuation maps. Quantitative analysis was performed for both datasets to assess the impact of MR-based attenuation correction to absolute PET activity measurements as well as target-to-reference ratio (SUVR). Clinical assessment was also performed by a nuclear medicine physician to determine amyloid status based on the criteria in the Food and Drug Administration prescribing information for florbetapir. Results: MR-based attenuation correction led to underestimation of PET activity for most parts of the brain, with a small overestimation for deep brain regions. There was also an overestimation of SUVRs with cerebellar reference. SUVR measurements obtained from the 2 attenuation-correction methods were strongly correlated. Clinical assessment of amyloid status resulted in identical classification as positive or negative regardless of the attenuation-correction methods. Conclusion: MR-based attenuation correction causes biases in quantitative measurements. The biases may be accounted for by a linear model, although the spatial variation cannot be easily modeled. The quantitative differences, however, did not affect clinical assessment as positive or negative. |
| Databáze: | OpenAIRE |
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