Notghi Alp, O'Brien Joseph, Clarke Elizabeth A, Thomson William H
City Hospital, Sandwell and West Birmingham Hospitals NHS Trust, Dudley Road, Birmingham, B18 7QH, UK.
Nucl Med Commun. 2010 Mar;31(3):217-26. doi: 10.1097/MNM.0b013e328334fc53.
In this study, we have investigated the feasibility of a 180 degrees DaTSCAN brain SPECT acquisition. This technique has the advantage of being 'open view' for the patient and therefore more acceptable for claustrophobic patients. It also enables easier access for a technologist to hold the patient's head during acquisition to reduce movement in confused patients or in those with severe tremor.
In the first part of this study, we validated the practicality and image quality of a 180 degrees acquisition using a DaTSCAN Alderson head phantom with different camera configurations on GE Infinia and Philips AXIS gamma cameras. The effect on image quality of using half the acquisition time was also assessed. In the second part of the study, 50 sets of patient data were reprocessed by reconstructing half of the 360 degrees data to mimic a single-head 180 degrees acquisition. The 180 degrees images were then compared with 360 degrees images for the same patient using a visual score system. The effect of half-time 180 degrees data acquisition on quantification was also assessed using GE QuantiSPECT software.
All phantom images from 180 degrees acquisitions contained some degree of distortion at the periphery, but clearly retain the presence of centrally positioned caudate and putamen; hence 180 degrees acquisitions were deemed to produce clinically useful diagnostic images. The shorter (half) acquisition time leads to noisier but acceptable images for all configurations. In the patient study, there was complete agreement between the two reporters with no clinical difference in the diagnostic accuracy between the 180 degrees and 360 degrees images. However, 6 of 50 180 degrees images were marked as poor quality but reportable, compared with 0 of 50 in 360 degrees images. Quantification gave consistently lower nuclei to background ratio values for 180 degrees compared with 360 degrees for normal and abnormal patients.
It is possible to obtain diagnostic DaTSCAN images using 180 degrees acquisition in difficult patients. The total length of the study may also be shortened by half using L-mode or V-mode camera head configuration.
在本研究中，我们调查了180°DaTSCAN脑SPECT采集的可行性。该技术的优点是对患者而言为“开放式视野”，因此对于幽闭恐惧症患者更易接受。它还使技术人员在采集过程中更容易扶住患者头部，以减少意识模糊患者或严重震颤患者的头部运动。
在本研究的第一部分，我们使用DaTSCAN Alderson头部模型，在GE Infinia和飞利浦AXISγ相机上采用不同的相机配置，验证了180°采集的实用性和图像质量。还评估了使用一半采集时间对图像质量的影响。在研究的第二部分，通过重建360°数据的一半来重新处理50组患者数据，以模拟单头180°采集。然后使用视觉评分系统将同一患者的180°图像与360°图像进行比较。还使用GE QuantiSPECT软件评估了180°数据半时采集对定量分析的影响。
180°采集的所有模型图像在外围都存在一定程度的失真，但清晰地保留了位于中心位置的尾状核和壳核；因此，180°采集被认为可产生临床有用的诊断图像。较短（一半）的采集时间会导致所有配置的图像噪声增加，但仍可接受。在患者研究中，两位报告者之间完全一致，180°和360°图像的诊断准确性在临床上没有差异。然而，50张180°图像中有6张被标记为质量较差但可报告，而360°图像中50张里有0张。与360°相比，正常和异常患者的180°定量分析得出的核与背景比值始终较低。
对于情况复杂的患者，使用180°采集有可能获得诊断性DaTSCAN图像。使用L模式或V模式摄像头配置，研究的总时长也可能缩短一半。
