Nömayr Anton, Römer Wolfgang, Strobel Daniel, Bautz Werner, Kuwert Torsten
Clinic of Nuclear Medicine, University of Erlangen/Nürnberg, Germany.
Nucl Med Commun. 2006 Jun;27(6):521-8. doi: 10.1097/00006231-200606000-00008.
The anatomical accuracy of hardware-based registration of skeletal single photon emission computed tomography (SPECT) and X-ray computerized tomography (CT) has as yet not been studied. The aim of this study was to evaluate this variable in the lower spine for a newly introduced hybrid SPECT/spiral-CT camera.
In 22 patients referred for degenerative joint disease or tumours, whole-body bone scintigraphy including hybrid SPECT/spiral CT of the lower spine was performed. Subsequent analyses were performed on these pairs of images as well as on data sets obtained after using a rigid automated fusion procedure in addition. Two observers independently measured the distances between the visually determined centres of gravity of the CT and SPECT representation of the fourth and fifth lumbar vertebral body in the X-, Y- and Z-directions (X-, Y- and Z-distances).
The distances determined by the two observers for the two vertebral bodies correlated significantly and were averaged for further analysis. For hybrid SPECT/spiral CT without consecutive automated registration, the mean X-, Y- and Z-distances were 1.6+/-1.9 mm, 1.7+/-1.3 mm and 0.9+/-0.5 mm, respectively. Additional automated registration lowered these values to 1.2+/-0.9 mm, 1.1+/-0.7 mm and 0.8+/-0.4 mm, respectively. The difference for the Y-distance proved statistically significant (P<0.05). Additional automated registration significantly reduced the number of subjects in whom at least one of the distances determined was greater than the SPECT pixel size of 4.6 mm from 14% (n=3) to 0% (P<0.05).
Hardware-based fusion between skeletal SPECT and CT offers a nearly perfect data match in the lower spine. The additional use of a tool for automated rigid registration has the potential to reduce the error of alignment even further and may be useful in patients with reduced compliance leading to movements between the two examinations.
基于硬件的骨骼单光子发射计算机断层扫描（SPECT）与X射线计算机断层扫描（CT）配准的解剖学准确性尚未得到研究。本研究的目的是评估一种新引入的混合SPECT/螺旋CT相机在下脊柱中的这一变量。
对22例因退行性关节疾病或肿瘤就诊的患者进行了包括下脊柱混合SPECT/螺旋CT的全身骨闪烁显像。随后对这些图像对以及在使用刚性自动融合程序后获得的数据集进行分析。两名观察者独立测量在X、Y和Z方向（X、Y和Z距离）上视觉确定的第四和第五腰椎椎体CT和SPECT图像重心之间的距离。
两名观察者确定的两个椎体的距离显著相关，并进行平均以进行进一步分析。对于没有连续自动配准的混合SPECT/螺旋CT，平均X、Y和Z距离分别为1.6±1.9mm、1.7±1.3mm和0.9±0.5mm。额外的自动配准将这些值分别降低到1.2±0.9mm、1.1±0.7mm和0.8±0.4mm。Y距离的差异具有统计学意义（P<0.05）。额外的自动配准显著减少了至少一个确定距离大于SPECT像素大小4.6mm的受试者数量，从14%（n=3）降至0%（P<0.05）。
骨骼SPECT与CT之间基于硬件的融合在下脊柱中提供了近乎完美的数据匹配。额外使用自动刚性配准工具有可能进一步减少配准误差，对于在两次检查之间因顺应性降低导致移动的患者可能有用。
