Garcia Carlos A, Van Nostrand Douglas, Atkins F, Acio E, Butler C, Esposito G, Kulkarni K, Majd M
Division of Nuclear Medicine, Department of Medicine, Washington Hospital Center, 110 Irving Street, NW, Washington, DC 20010, USA.
Mol Imaging Biol. 2006 Jan-Feb;8(1):24-9. doi: 10.1007/s11307-005-0030-3.
Brown fat uptake of 2-deoxy-2-[F-18]fluoro-D: -glucose (FDG) on a positron emission tomography (PET) scan limits the ability to assess for cancer. Drugs such as benzodiazepine, propranolol, and reserpine have been proposed to reduce this uptake, but the studies have been either small clinical or preclinical trials. As an alternative, we evaluated the effect of controlling the patient's environmental temperature on brown fat uptake of FDG.
From January 1, 2002 to November 30, 2004, patients were identified who had (1) a pattern of FDG uptake in the neck/paravertebral areas suggestive of brown fat, (2) a repeat FDG-PET scan after control of the patient's environmental temperature, and (3) no evidence of cancer in the neck/paravertebral areas by other diagnostic methods. For the follow-up PET scan, all patients wore warm clothing and avoided exposure to cold air during their transit to our facility. After arrival, patients were kept in a separate temperature-controlled room (at least 75 degrees F) for 15 minutes to two hours before FDG injection as well as during the uptake phase. Four physicians blindly and retrospectively assessed the FDG uptake in the neck and paravertebral regions on all initial and temperature-controlled PET scans by visually grading the radioactivity on a semiquantitative scale (0 = background, 1+ = background but <liver, 2+ = equal to liver, 3+ >liver). The changes in maximal SUVs were determined in the left and right neck region. Data were evaluated using a two-tail t-test.
Ten patients met the above criteria. The median age was 32 years with a range of 11-58 years. In comparing the semiquantitative uptake and the SUVs of FDG in the neck and paravertebral areas on the initial PET scan to the temperature-controlled PET scan, the mean decrease and the standard deviation of the decrease demonstrated a statistically significant decrease in with P values range from <0.02 to <0.001.
Controlling the patient's environmental temperature prior to the dosing and during the uptake phase can significantly reduce FDG uptake in brown fat in the neck and paravertebral areas. Further studies are warranted to determine the most effective protocol to control the patient's environmental temperature in order to minimize brown fat uptake.
正电子发射断层扫描（PET）中棕色脂肪对2-脱氧-2-[F-18]氟-D-葡萄糖（FDG）的摄取限制了评估癌症的能力。已提出使用苯二氮卓、普萘洛尔和利血平等药物来减少这种摄取，但这些研究要么是小型临床试验，要么是临床前试验。作为一种替代方法，我们评估了控制患者环境温度对棕色脂肪摄取FDG的影响。
从2002年1月1日至2004年11月30日，确定符合以下条件的患者：（1）颈部/椎旁区域有提示棕色脂肪的FDG摄取模式；（2）在控制患者环境温度后进行重复FDG-PET扫描；（3）通过其他诊断方法在颈部/椎旁区域无癌症证据。在后续的PET扫描中，所有患者在前往我们机构的途中都穿着保暖衣物并避免暴露于冷空气。到达后，在注射FDG前以及摄取阶段，患者被安置在一个单独的温度控制房间（至少75华氏度）中15分钟至2小时。四名医生通过在半定量量表上对放射性进行视觉分级（0 = 背景，1+ = 高于背景但低于肝脏，2+ = 等于肝脏，3+ >肝脏），对所有初始和温度控制的PET扫描中颈部和椎旁区域的FDG摄取进行盲法回顾性评估。确定左、右颈部区域最大SUV的变化。使用双尾t检验评估数据。
10名患者符合上述标准。中位年龄为32岁，范围为11 - 58岁。将初始PET扫描与温度控制PET扫描中颈部和椎旁区域FDG的半定量摄取和SUV进行比较，平均下降幅度和下降的标准差显示出统计学上的显著下降，P值范围从<0.02至<0.001。
在给药前和摄取阶段控制患者的环境温度可显著降低颈部和椎旁区域棕色脂肪对FDG的摄取。有必要进行进一步研究以确定控制患者环境温度的最有效方案，以使棕色脂肪摄取最小化。
