Visualization of brown adipose tissue with 99mTc-methoxyisobutylisonitrile on SPECT/CT.
Brown adipose tissue (BAT) is retained into adulthood in some patients. It has been imaged using several radiopharmaceuticals, including (18)F-FDG. Using SPECT/CT, we assessed whether and how frequently uptake of (99m)Tc-methoxyisobutylisonitrile ((99m)Tc-MIBI) was present in expected locations of BAT.


METHODS
A total of 205 SPECT/CT scans using (99m)Tc-MIBI for parathyroid imaging were reviewed for the presence of (99m)Tc-MIBI uptake in expected locations of BAT.


RESULTS
We detected (99m)Tc-MIBI uptake in BAT in 13 of 205 patients (6.3%). When BAT was visualized, it was detected on both early and delayed scans. The patients with (99m)Tc-MIBI uptake in BAT were younger than the patients with no (99m)Tc-MIBI uptake (P=0.044).


CONCLUSIONS
Uptake of (99m)Tc-MIBI in BAT is relatively common in this adult patient population and should not be confused with (99m)Tc-MIBI-avid-tumors. SPECT/CT can be useful for defining such tracer uptake as a normal physiologic variant.
Goetze
Sibyll
S
Division of Nuclear Medicine, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland 21287-0817, USA.
Lavely
William C
WC
Ziessman
Harvey A
HA
Wahl
Richard L
RL
D002001:Adipose Tissue, Brown / Q000000981:diagnostic imaging*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*
D017256:Technetium Tc 99m Sestamibi