Kitamura Yoshiyuki, Baba Shingo, Isoda Takuro, Maruoka Yasuhiro, Kawanami Satoshi, Himuro Kazuhiko, Sasaki Masayuki, Honda Hiroshi
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Asia Ocean J Nucl Med Biol. 2017 Winter;5(1):30-36. doi: 10.22038/aojnmb.2016.7747.
In positron emission tomography (PET) studies, thoracic movement under free-breathing conditions is a cause of image degradation. Respiratory gating (RG) is commonly used to solve this problem. Two different methods, i.e., phase-gating (PG) and amplitude-gating (AG) PET, are available for respiratory gating. It is important to know the strengths and weaknesses of both methods when selecting an RG method for a given patient. We conducted this study to clarify whether AG or PG is preferable for measuring fluorodeoxyglucose (FDG) accumulation in lung adenocarcinoma and to investigate patient conditions which are most suitable for AG and PG methods.
A total of 31 patients (11 males, 20 females; average age: 70.1±11.6 yrs) with 44 lung lesions, diagnosed as lung adenocarcinoma between April 2012 and March 2013, were investigated. Whole-body FDG-PET/CT scan was performed with both PG and AG methods in all patients. The maximum standardized uptake value (SUV) of PG, AG, and the control data of these two methods were measured, and the increase ratio (IR), calculated as IR(%)= (Post - Pre)/Pre × 100, was calculated. The diameter and position of lung lesions were also analyzed. We defined an 'effective lesion' of PG (or AG) as a lesion which showed a higher IR compared to AG (or PG). 8 (25.8%).
The average SUV and average IR were 8.99±7.94 and %21.4±25.6 in PG and 7.60±6.70 and %4.0±14.4 in AG, respectively. Although there was no significant difference between the average SUV of PG and AG (P=0.09), the average IR of PG was significantly higher than that of AG (P<0.01). The number of PG- and AG-effective lesions was 32 (72.7%) and 12 (28.3%), respectively. There was no significant difference in the average diameter or position of the lesions between the PG- and AG-effective lesions. There were 23 (74.2%) PG-effective and 8 (25.8%) AG-effective patients. No significant difference was observed in sex or age between PG- and AG-effective patients.
The PG method was more effective for measuring FDG accumulation of lung lesions under free-breathing conditions in comparison with the AG method.
在正电子发射断层扫描（PET）研究中，自由呼吸条件下的胸部运动是图像退化的一个原因。呼吸门控（RG）常用于解决此问题。有两种不同的方法，即相位门控（PG）和幅度门控（AG）PET，可用于呼吸门控。在为特定患者选择RG方法时，了解这两种方法的优缺点很重要。我们进行这项研究以阐明在测量肺腺癌中氟脱氧葡萄糖（FDG）蓄积时AG还是PG更可取，并调查最适合AG和PG方法的患者情况。
对2012年4月至2013年3月期间诊断为肺腺癌的31例患者（11例男性，20例女性；平均年龄：70.1±11.6岁）的44个肺部病变进行了研究。所有患者均采用PG和AG方法进行全身FDG-PET/CT扫描。测量PG、AG的最大标准化摄取值（SUV）以及这两种方法的对照数据，并计算增加率（IR），计算公式为IR(%) = (Post - Pre)/Pre × 100。还分析了肺部病变的直径和位置。我们将PG（或AG）的“有效病变”定义为与AG（或PG）相比IR更高的病变。8例（25.8%）。
PG的平均SUV和平均IR分别为8.99±7.94和21.4±25.6%，AG的分别为7.60±6.70和4.0±14.4%。虽然PG和AG的平均SUV之间无显著差异（P = 0.09），但PG的平均IR显著高于AG（P<0.01）。PG有效病变和AG有效病变的数量分别为32例（72.7%）和12例（28.3%）。PG有效病变和AG有效病变之间病变的平均直径或位置无显著差异。有23例（74.2%）PG有效患者和8例（25.8%）AG有效患者。PG有效患者和AG有效患者在性别或年龄上未观察到显著差异。
与AG方法相比，PG方法在自由呼吸条件下测量肺部病变的FDG蓄积更有效。
