Department of Nuclear Medicine, University Hospital Bonn, Bonn, Germany.
J Nucl Med. 2011 Jul;52(7):1063-7. doi: 10.2967/jnumed.110.083626. Epub 2011 Jun 16.
(99m)Tc-macroaggregated albumin ((99m)Tc-MAA) scanning precedes radioembolization of the liver to detect extrahepatic shunting to the lung or gastrointestinal tract. Despite strict preventive measures in the production of (99m)Tc-MAA and in scanning protocols, the images frequently show a gastric concentration of free (99m)Tc-pertechnetate, hindering accurate evaluation of the gastroduodenal region. Our aim was to evaluate whether oral administration of sodium perchlorate (NaClO(4)) before (99m)Tc-MAA scanning will improve its accuracy by blocking free (99m)Tc-pertechnetate gastric uptake.
In 144 patients, 171 diagnostic hepatic angiograms combined with a (99m)Tc-MAA scan were performed; 86 angiograms were performed after oral administration of NaClO(4), and 85 were performed without this premedication. Clinical follow-up, esophagogastroduodenoscopy, and angiography served as reference standards.
(99m)Tc-MAA studies showed tracer uptake in the gastric region of 25 patients who did not receive NaClO(4). The uptake was interpreted as a free (99m)Tc-pertechnetate concentration in 21 studies and as a (99m)Tc-MAA accumulation in 4 studies. In 5 patients with a free (99m)Tc-pertechnetate concentration, aberrant vessels were detected in angiographic reexamination, and 3 patients developed gastrointestinal ulcer. In 7 studies, gastric findings viewed pretherapeutically as free (99m)Tc-pertechnetate were retrospectively classified as equivocal. Of the patients receiving NaClO(4), 2 showed gastric accumulation of (99m)Tc-MAA but no equivocal or free (99m)Tc-pertechnetate. Oral administration of NaClO(4) increased the negative predictive value and accuracy of the test concerning the detection of gastric perfusion from 68% and 69%, respectively, to 93% and 94%, respectively.
Oral administration of NaClO(4) before the test angiogram with (99m)Tc-MAA resulted in effective avoidance of free (99m)Tc-pertechnetate concentration and, consequently, of equivocal findings in the gastroduodenal region. This technique increased test accuracy and reporter confidence, saved time in reviewing the angiograms, and can improve treatment planning and reduce therapeutic side effects.
评估在 (99m)Tc-巨聚合白蛋白 ((99m)Tc-MAA) 扫描前口服高氯酸钠 (NaClO(4)) 是否可以通过阻止游离 (99m)Tc-高锝酸盐胃摄取来提高其准确性。
在 144 例患者中，共进行了 171 次诊断性肝血管造影术和 (99m)Tc-MAA 扫描；86 次血管造影术在口服 NaClO(4)后进行，85 次血管造影术未进行该预处理。临床随访、食管胃十二指肠镜检查和血管造影术作为参考标准。
在未接受 NaClO(4)的 25 例患者中，(99m)Tc-MAA 研究显示胃区有示踪剂摄取。21 次研究中摄取被解释为游离 (99m)Tc-高锝酸盐浓度，4 次研究中摄取被解释为 (99m)Tc-MAA 聚集。在 5 例游离 (99m)Tc-高锝酸盐浓度的患者中，血管造影复查发现异常血管，3 例发生胃肠道溃疡。在 7 项研究中，治疗前胃发现被视为游离 (99m)Tc-高锝酸盐的被回顾性分类为不确定。在接受 NaClO(4)的患者中，有 2 例显示 (99m)Tc-MAA 胃积聚，但无不确定或游离 (99m)Tc-高锝酸盐。在测试前口服 NaClO(4)可使检测胃灌注的试验的阴性预测值和准确性分别从 68%和 69%提高到 93%和 94%。
在 (99m)Tc-MAA 试验血管造影前口服 NaClO(4)可有效避免游离 (99m)Tc-高锝酸盐浓度，从而避免胃十二指肠区域出现不确定结果。该技术提高了试验的准确性和报告者的信心，节省了血管造影复查时间，并可改善治疗计划，减少治疗副作用。
