TY - JOUR

T1 - Hybrid FDG PET/MRI vs. FDG PET and CT in patients with suspected dementia

T2 - A comparison of diagnostic yield and propagated influence on clinical diagnosis and patient management

AU - Kaltoft, Nicolai Stefan

AU - Marner, Lisbeth

AU - Larsen, Vibeke Andree

AU - Hasselbalch, Steen Gregers

AU - Law, Ian

AU - Henriksen, Otto Mølby

PY - 2019

Y1 - 2019

N2 - BACKGROUND: Both 18F-fluoro-deoxy-glucose (FDG) positron emission tomography (PET), computed tomography (CT) and magnetic resonance imaging (MRI) are routinely used in the evaluation of memory clinic patients. Hybrid PET/MR systems now allow simultaneous PET and MRI imaging within the duration of the PET emission scan.PURPOSE: To compare the diagnostic yield of PET/MRI using an abbreviated MR protocol with that of separate PET and CT in a mixed memory clinic population, and the propagated influences on clinical diagnosis and patient management.MATERIAL AND METHODS: Consecutive memory clinic patients (n = 78) undergoing both CT and hybrid FDG PET/MRI scans were identified retrospectively. MRI and CT were separately evaluated for vascular and structural pathology. PET scans were classified according to the presence of neurodegenerative or vascular disease using CT or MRI, respectively, for anatomical guiding. A memory clinic expert assessed the clinical impact of the additional findings and/or change of PET classification achieved by MRI anatomical guiding as compared to CT guiding.RESULTS: MRI lead to significantly higher Fazekas scores, higher medial temporal and global cortical atrophy scores, and identified more patients with infarcts (28 vs 8, p<0.001) compared to CT. MRI changed PET classification in 13 (17%) patients. Addition of MRI to CT had minor clinical impact in 4/78 (5%) and major clinical impact in 13/78 (17%) of patients.CONCLUSION: The study demonstrates the capabilities of PET/MRI systems for routine clinical imaging of memory clinic patients, and that even an abbreviated hybrid PET/MRI protocol provides significant additional information influencing clinical diagnosis and patient management in a substantial fraction of patients when compared to separate PET and CT.

AB - BACKGROUND: Both 18F-fluoro-deoxy-glucose (FDG) positron emission tomography (PET), computed tomography (CT) and magnetic resonance imaging (MRI) are routinely used in the evaluation of memory clinic patients. Hybrid PET/MR systems now allow simultaneous PET and MRI imaging within the duration of the PET emission scan.PURPOSE: To compare the diagnostic yield of PET/MRI using an abbreviated MR protocol with that of separate PET and CT in a mixed memory clinic population, and the propagated influences on clinical diagnosis and patient management.MATERIAL AND METHODS: Consecutive memory clinic patients (n = 78) undergoing both CT and hybrid FDG PET/MRI scans were identified retrospectively. MRI and CT were separately evaluated for vascular and structural pathology. PET scans were classified according to the presence of neurodegenerative or vascular disease using CT or MRI, respectively, for anatomical guiding. A memory clinic expert assessed the clinical impact of the additional findings and/or change of PET classification achieved by MRI anatomical guiding as compared to CT guiding.RESULTS: MRI lead to significantly higher Fazekas scores, higher medial temporal and global cortical atrophy scores, and identified more patients with infarcts (28 vs 8, p<0.001) compared to CT. MRI changed PET classification in 13 (17%) patients. Addition of MRI to CT had minor clinical impact in 4/78 (5%) and major clinical impact in 13/78 (17%) of patients.CONCLUSION: The study demonstrates the capabilities of PET/MRI systems for routine clinical imaging of memory clinic patients, and that even an abbreviated hybrid PET/MRI protocol provides significant additional information influencing clinical diagnosis and patient management in a substantial fraction of patients when compared to separate PET and CT.

KW - Adolescent

KW - Adult

KW - Dementia/diagnostic imaging

KW - Female

KW - Fluorodeoxyglucose F18/administration & dosage

KW - Humans

KW - Male

KW - Positron-Emission Tomography

KW - Retrospective Studies

KW - Tomography, X-Ray Computed

U2 - 10.1371/journal.pone.0216409

DO - 10.1371/journal.pone.0216409

M3 - Journal article

C2 - 31048902

VL - 14

JO - PLoS ONE

JF - PLoS ONE

SN - 1932-6203

IS - 5

M1 - e0216409

ER -