Miraldi F, Vesselle H, Faulhaber P F, Adler L P, Leisure G P
Department of Radiology, University Hospitals of Cleveland, School of Medicine, Case Western Reserve University, Ohio, USA.
Clin Nucl Med. 1998 Jan;23(1):3-7. doi: 10.1097/00003072-199801000-00002.
Positron emission tomography (PET) with fluorine-18 labeled deoxyglucose (FDG) can detect tumor recurrences in surgical patients that are otherwise difficult to assess by CT, as well as distant metastases and small malignant nodes that are not identified by other imaging modalities. However, the evaluation of such malignancy is complicated by urinary and colonic concentrations of FDG. Methods and examples of the elimination of artifactual accumulation of FDG in PET imaging of the abdomen and pelvis are presented.
Elimination of artifactual accumulation requires patient preparation that begins with cleansing of the colon using an isosmotic solution taken the evening prior to examination. Approximately 500 MBq of F-18 FDG is intravenously administered upon arrival at the PET facility and then the patient is hydrated. After administration of furosemide, a Foley catheter with a drainage bag is placed and the patient is then scanned. Just prior to scanning over the pelvis, normal saline is delivered retrogradely into the urinary bladder. At the end of scanning, the patient voids and repeated pelvic images are obtained.
These routines yield a clean scanning field. Lesions that will generally be missed because they are obscured by FDG accumulations along the colon or in the kidneys, ureters, or bladder are better visualized and identified with greater confidence. Artifacts that lead to misinterpretation also are reduced.
Elimination of artifactual accumulation of FDG in the colon and urinary system is essential if primary cancer, associated adenopathy, or subtle recurrences are to be evaluated in FDG PET imaging of the abdomen and pelvis.
使用氟-18标记的脱氧葡萄糖（FDG）的正电子发射断层扫描（PET）能够检测出手术患者中难以通过CT评估的肿瘤复发情况，以及其他成像方式无法识别的远处转移灶和小的恶性淋巴结。然而，FDG在尿液和结肠中的浓聚会使对这种恶性病变的评估变得复杂。本文介绍了在腹部和盆腔PET成像中消除FDG伪影积聚的方法及示例。
消除伪影积聚需要患者进行准备，首先在检查前一晚使用等渗溶液清洁结肠。患者到达PET设备后静脉注射约500MBq的F-18 FDG，然后进行水化。注射速尿后，放置带有引流袋的Foley导管，随后对患者进行扫描。在对盆腔进行扫描前，将生理盐水逆行注入膀胱。扫描结束时，患者排尿，并获取重复的盆腔图像。
这些常规操作可产生清晰的扫描视野。那些通常因结肠或肾脏、输尿管或膀胱中FDG积聚而被掩盖从而漏诊的病变，能得到更好的显示，并能更有把握地识别。导致误诊的伪影也会减少。
在对腹部和盆腔进行FDG PET成像以评估原发性癌症、相关腺病或微小复发时，消除结肠和泌尿系统中FDG的伪影积聚至关重要。
