Reiche W, Grundmann M, Huber G
Institut für Neuroradiologie, Universität des Saarlandes, Homburg/Saar.
Radiologe. 1995 Nov;35(11):838-43.
For effective drug therapy of Parkinson's syndrome (PS), it is necessary to distinguish between idiopathic and secondary genesis and PS in neuronal systemic degeneration. [123I]Iodobenzamide ([123I] IBZM) is a radiolabelled benzamide and binds specifically to the cerebral dopamine receptor (D2) in the basal ganglia. The purpose of this study was to determine the value of the [123I]IBZM D2-receptor SPECT in the differential diagnosis of PS. A total of 38 patients (20 females, 18 males; age 61 +/- 13.3 years), with typical extrapyramidal symptoms were investigated. Twenty suffered from idiopathic and 11 from secondary PS. Seven patients in whom a neurological disease could be excluded, served as controls. SPECT data were acquired 90 min after i.v. injection of 185-200 MBq [123I]IBZM. After reconstruction with a Butterworth filter (cutoff frequency 0.5) and attenuation correction (coefficient 0.12 cm(-1)) we quantify the IBZM basal ganglia uptake as ratio to teh frontal D2-receptor-free cortex (BG/FC). The patients with idiopathic PS (IPS) and the controls revealed high and specific IBZM uptake in the basal ganglia compared to the adjacent frontal brain tissue (IPS: BG/FC = 1.44 +/- 0.10; controls: BG/FC = 1.48 +/- 0.10). A significant decreased striatal IBZM uptake is found in cases with secondary PS (BG/FC = 1.25 +/- 0.10; p<0.0001, t-test compared to controls and IPS). The patient group with IPS can be subdivided into patients without L-dopatherapy (BG/FC = 1.49 +/- 0.07), patients with longstanding L-dopa-therapy demonstrating significantly decreased striatal IBZM uptake (BG/FC = 1.31 +/- 0.04; p<0.0001, t-test compared to controls and other IPS), which correlates pathophysiological with a reduction of free D2 receptors, and patients with de novo PS showing a slight increased striatal IBZM uptake (BG/FC = 1.56 +/- 0.05), which represents D2-receptor stimulation. [123I]IBZM-SPECT is a sensitive and non-invasive test for striatal D2-receptor density and activity which permits relatively clear discrimination between idiopathic and secondary PS and yields important information for differential therapy.
为实现帕金森综合征（PS）的有效药物治疗，有必要区分特发性和继发性病因以及神经元系统变性中的PS。[123I]碘苯甲酰胺（[123I] IBZM）是一种放射性标记的苯甲酰胺，可特异性结合基底节中的脑多巴胺受体（D2）。本研究的目的是确定[123I]IBZM D2受体单光子发射计算机断层扫描（SPECT）在PS鉴别诊断中的价值。共对38例有典型锥体外系症状的患者（20例女性，18例男性；年龄61±13.3岁）进行了研究。其中20例患有特发性PS，11例患有继发性PS。7例可排除神经系统疾病的患者作为对照。静脉注射185 - 200 MBq [123I]IBZM后90分钟采集SPECT数据。用巴特沃斯滤波器（截止频率0.5）重建并进行衰减校正（系数0.12 cm(-1)）后，我们将IBZM在基底节的摄取量量化为与额叶无D2受体皮质的比值（BG/FC）。特发性PS（IPS）患者和对照组与相邻额叶脑组织相比，基底节显示出高且特异的IBZM摄取（IPS：BG/FC = 1.44±0.10；对照组：BG/FC = 1.48±0.10）。继发性PS患者纹状体IBZM摄取显著降低（BG/FC = 1.25±0.10；p<0.0001，与对照组和IPS进行t检验）。IPS患者组可细分为未接受左旋多巴治疗的患者（BG/FC = 1.49±0.07）、长期接受左旋多巴治疗且纹状体IBZM摄取显著降低的患者（BG/FC = 1.31±0.04；p<0.0001，与对照组和其他IPS进行t检验），这在病理生理上与游离D2受体减少相关，以及新发PS患者，其纹状体IBZM摄取略有增加（BG/FC = 1.56±0.05），这代表D2受体刺激。[123I]IBZM - SPECT是一种用于检测纹状体D2受体密度和活性的敏感且无创的检查，它能够相对清晰地区分特发性和继发性PS，并为鉴别治疗提供重要信息。
