Teruaki Chiba; Makoto Hosono; Yoshihiro Komeya; Sung-Woon Im; Ryuichiro Ashikaga; Taro Shimono; Norio Tsuchiya; Masahiro Okada; Kazushi Hanada; Yukinobu Yagyu; Yasumasa Nishimura; Takamichi Murakami
ANNALS OF NUCLEAR MEDICINE SPRINGER 22 (6) 513 - 519 0914-7187 2008/07
Objective The objective of our study was to evaluate diagnostic ability and features of quantitative indices of three modalities: uptake rate on norcholesterol scintigraphy, computed tomography (CT) attenuation value, and fat suppression on chemical-shift magnetic resonance imaging (MRI) for characterizing adrenal adenomas.
Methods Image findings of norcholesterol scintigraphy, CT, and MRI were reviewed for 78 patients with functioning (n = 48) or nonfunctioning (n = 30) adrenal masses. The norcholesterol uptake rate, attenuation value on unenhanced CT, and suppression on in-phase to opposed-phase MRI were measured for adrenal masses.
Results The norcholesterol uptake rate, CT attenuation value, and MR suppression index showed the sensitivity of 60%, 82%, and 100%, respectively, for functioning adenomas of < 2.0 cm, and 96%, 79%, and 67%, respectively, for those of >= 2.0 cm. A statistically significant correlation was observed between size and norcholesterol uptake, and between CT attenuation value and MR suppression index. Regarding norcholesterol uptake, the adenoma-to-contralateral gland ratio was significantly higher in cortisol releasing than in aldosterone-releasing adenomas.
Conclusions The norcholesterol uptake rate was reliable for characterization of adenomas among adrenal masses of >= 2.0 cm. CT attenuation value and MR suppression index were well correlated with each other, and were useful regardless of mass size.