Use of 3.0-T MRI for stereotactic radiosurgery planning for treatment of brain metastases: a single-institution retrospective review.
OBJECTIVE
To investigate the efficacy of 3.0-T magnetic resonance imaging (MRI) for detecting brain metastases for stereotactic radiosurgery (SRS) planning.


METHODS
All adult patients scheduled for SRS treatment for brain metastases at our institution between October 2005 and January 2008 were eligible for analysis. All patients underwent radiosurgery treatment planning 3.0-T MRI on the day of scheduled radiosurgery and a diagnostic 1.5-T MRI in the days or weeks prior to radiosurgery for comparison. Both scans were interpreted by neuroradiologists who reported their findings in the radiology reports. We performed a retrospective review of the radiology reports to determine the number of brain metastases identified using each MRI system.


RESULTS
Of 254 patients scheduled for treatment from October 2005 to January 2008, 138 patients had radiology reports that explicitly described the number of metastases identified on both scans. With a median interval of 17 days (range, 1-82) between scans, the number of metastases detected using 1.5-T MRI system ranged from 1 to 5 and from 1 to 8 using the 3.0 T-MRI system. Twenty-two percent of patients were found to have a greater number of metastases with the 3.0 T-MRI system. The difference in number of metastases detected between the two scans for the entire cohort ranged from 0 to 6. Neither histology (p = 0.52 by chi-sq test) nor time between scans (p = 0.62 by linear regression) were significantly associated with the difference in number of metastases between scans.


CONCLUSIONS
The 3.0-T MRI system appears to be superior to a 1.5-T MRI system for detecting brain metastases, which may have significant implications in determining the appropriate treatment modality. Our findings suggest the need for a prospectively designed study to further evaluate the use of a 3.0 T-MRI system for stereotactic radiosurgery planning in the treatment of brain metastases.
Saconn
Paul A
PA
Department of Radiation Oncology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.
Shaw
Edward G
EG
Chan
Michael D
MD
Squire
Sarah E
SE
Johnson
Annette J
AJ
McMullen
Kevin P
KP
Tatter
Stephen B
SB
Ellis
Thomas L
TL
Lovato
James
J
Bourland
J Daniel
JD
Ekstrand
Kenneth E
KE
DeGuzman
Allan F
AF
Munley
Michael T
MT
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001932:Brain Neoplasms / Q000556:secondary* / Q000601:surgery*; D016009:Chi-Square Distribution; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000706:statistics & numerical data; D008499:Medical Records / Q000706:statistics & numerical data; D008875:Middle Aged; D016634:Radiosurgery; D012189:Retrospective Studies; D013997:Time Factors; D055815:Young Adult