Bai Jingming, Hashimoto Jun, Ogawa Koichi, Nakahara Tadaki, Suzuki Takayuki, Kubo Atsushi
21st Century Center of Excellence Program, School of Medicine, Keio University, Tokyo, Japan.
Ann Nucl Med. 2007 Jan;21(1):25-32. doi: 10.1007/BF03033996.
The aim of this study was to elucidate the clinical usefulness of scatter correction with an artificial neural network (ANN) in 99mTc and 123I dual-isotope SPECT.
Two algorithms for ANN scatter correction were tested: ANN-10 and ANN-3 employing 10 and 3 energy windows for data acquisition, respectively. Three patients underwent myocardial or brain SPECT with one of the following combinations of radiopharmaceuticals administered: 99mTc-tetrofosmin and 123I-metaiodobenzylguanidine (MIBG), 99mTc-methoxyisobutylisonitrile (MIBI) and 123I-beta-methyl-paraiodophenyl-pentadecanoic acid (BMIPP), or 99mTc-ethyl-cistainate dimmer (ECD) and 123I-iomazenil. The patients were also referred for single-isotope imaging incorporating conventional triple-energy window (TEW) scatter correction. Crosstalk- and scatter-corrected 99mTc- and 123I-SPECT images in dual-isotope acquisition with ANN were compared with those in single-isotope acquisition.
The ANN method well separated 123I and 99mTc primary photons. Although ANN-10 yielded images of poor quality, ANN-3 offered comparable image quality with the single-isotope scan without significant increase of acquisition time.
The proposed method is clinically useful because it provides various combinations of information without anatomical misregistration with one acquisition.
本研究的目的是阐明人工神经网络（ANN）散射校正在99mTc和123I双同位素SPECT中的临床应用价值。
测试了两种用于ANN散射校正的算法：分别采用10个和3个能量窗进行数据采集的ANN-10和ANN-3。3例患者接受心肌或脑SPECT检查，给予以下放射性药物组合之一：99mTc-替曲膦和123I-间碘苄胍（MIBG）、99mTc-甲氧基异丁基异腈（MIBI）和123I-β-甲基-对碘苯基十五烷酸（BMIPP），或99mTc-双半胱乙酯（ECD）和123I-碘美普尔。这些患者还接受了采用传统三能量窗（TEW）散射校正的单同位素成像。将ANN双同位素采集中经串扰和散射校正的99mTc和123I-SPECT图像与单同位素采集中的图像进行比较。
ANN方法能很好地分离123I和99mTc的原始光子。虽然ANN-10生成的图像质量较差，但ANN-3提供的图像质量与单同位素扫描相当，且采集时间没有显著增加。
所提出的方法在临床上是有用的，因为它通过一次采集就能提供各种信息组合，且不存在解剖学配准错误。
