Prone mammoPET acquisition improves the ability to fuse MRI and PET breast scans.
OBJECTIVE
This study compared prone acquisition of PET scans with traditional supine acquisition to improve fusion of PET scans with MRI scans and improve evaluation of enhancing breast lesions detected on MRI.


METHODS
MRI breast scans are acquired in the prone position using a breast coil to allow the breasts to hang pendant. An apparatus was fabricated to allow prone acquisition of PET scans. Fused scans from 2 patients acquired both prone and supine were contrasted with those from 3 patients acquired supine only. All 5 MRI scans were acquired on standard scanners. The PET scans were acquired with a PET/CT unit using a low-dose CT scan for attenuation correction. The PET and MRI volumes were matched twice (using a semiautomated registration method) by different operators. The additional value of fusion was judged using reports from the original (nonfused) MRI and PET, joint rereading of the volumes side by side, and examination of fused images.


RESULTS
Of 12 enhancing lesions on breast MRI, 7 demonstrated uptake on PET/CT. In the 3 supine-only cases, the fused images were not interpretable because of the marked distortion of the breasts. In the 2 prone cases, the fused images increased our confidence in characterizing a lesion as benign or malignant. Interpretations were confirmed by clinical follow up in 2 or histologic results in 3 patients.


CONCLUSIONS
PET MRI fusion is feasible and may assist in localizing lesions detected on either study. A more extensive study is underway to confirm the value of this fusion technique.
Moy
Linda
L
Department of Radiology, New York University School of Medicine, New York, NY 10016, USA.
Noz
Marilyn E
ME
Maguire
Gerald Q
GQ
Ponzo
Fabio
F
Deans
Abby E
AE
Murphy-Walcott
Antoinette D
AD
Kramer
Elissa L
EL
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D003287:Contrast Media; D005240:Feasibility Studies; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D016684:Prone Position; D012680:Sensitivity and Specificity; D016683:Supine Position
D003287:Contrast Media; D019786:Gadolinium DTPA