Scarred atrophic thyroid after I-131 therapy for Graves' disease documented at autopsy

Radioiodine is used as the definitive treatment of choice in most patients with Graves' hyperthyroidism. Most patients with Graves' disease eventually develop hypothyroidism following I-131 therapy and require thyroid hormone replacement therapy. We present a patient with aortic stenotic cardiac disease and coronary artery disease who suffered from fatigue, weight loss and atrial fibrillation. The patient's radionuclide study, as well as the T4 and TSH, confirmed Graves' disease and he received I-131 therapy. Our patient's development of hypothyroidism following 5 mCi I-131 therapy after seven days later was considered as unusual; in addition, our patient, at autopsy, had documented histopathologic changes confirming atrophy and fibrosis of the thyroid gland.     

Nodular hepatocellular carcinoma--treatment with intraarterial injection of I-131 Lipiodol

Twenty four patients with hepatocellular carcinoma who refused surgery or had unresectable tumor ranging 2.5 to 8.0 cm in size were treated with intrahepatic arterial injection of iodine-131-labeled iodized oil (I-131 Lipodol) in an attempt to achieve internal radiation of tumor. 555-2,220 MBq in 3-8 ml of I-131 Lipiodol was injected into the hepatic artery or proximal to the tumor feeding vessel depending on the tumor size. Tumor size reduction was observed in 88.9% of tumor smaller than 4.0 cm in diameter, 65.5% between 4.1 to 6.0 cm, and 25.0% of larger than 6.1cm, respectively. The tumor size reduction was corresponded to the gradual drop of serum AFP levels, decreased uptake on gallium-67 scintigraphy, and devascularization on follow-up angiography. Tumors having significant A-V shunts revealed further tumor growth. Adverse reactions from the treatment include fever, mild abdominal pain, nausea and elevation of transaminases. These have been mild and well-tolerated by the patients. This method was able to provide long term local control without complications related to thyroid, lung, GI tract and bone marrow.     

Location of aldosterone-producing adenomas with 131I-19-iodocholesterol.

We used 131I-19-iodocholesterol as an adrenal-imaging agent in 27 hypertensive patients who had biochemical evidence of abnormalities in the renin-angiotensin-aldosterone system. In 10 of 12 patients in whom the biochemical findings suggested the presence of an aldosterone-producing adenoma the adrenal uptake was asymmetric. The adenoma was subsequently confirmed in all eight patients in this group who underwent operation. In contrast, the adrenal uptake was asymmetric in only one of 13 patients with biochemical evidence of iodopathic hyperaldosteronism or low-renin essential hypertension. Two patients with adrenal carcinoma causing primary aldosteronism did not concentrate the isotope in their tumors. When metabolic studies suggest an aldosterone-producing adenoma, adrenal imaging with 131I-19-iodocholesterol may locate the tumor before operation.     

131I-β-CIT多巴胺转运蛋白显像的基础研究

用过氧乙酸法进行 1 31 I标记 β- CIT。以 MPTP连续 5 d注入猫股静脉内 ,建立 PD模型。取正常猫 6只、PD模型猫 3只 ,每只分别注入 74 MBq/ 0 .5 ml　 1 31 I- β- CIT,观察 4 h和 2 0 h时动物体内分布情况。将 74 MBq/0 .5 ml/只 1 31 I- β- CIT经股静脉分别注入正常组及 PD组猫体内 ,于注射后 0 .5、1、2、4、2 0 h进行脑显像 ,计算纹状体 1 31 I-β- CIT的特异性结合。结果显示 :标记物 1 31 I-β- CIT放化纯达 97.6 2 %± 0 .31%。室温下放置 4 h以及分别与水、人新鲜血清孵育 4 h后 ,放化纯平均值分别为 95 .33%± 0 .5 9%、95 .14 %± 0 .87%、95 .0 6 %± 0 .6 4 %。猫静脉注射 1 31 I- β- CIT后 ,放射性主要浓聚于纹状体区 ,其次为肺、肝、肾。以每克组织中放射性占总放射性计数的百分比计算 ,正常猫 4 h和 2 0 h纹状体 /小脑比值分别为 18.31± 3.5 0和 2 0 .5 1± 2 .2 3。 2 0 h PD猫纹状体 /小脑的比值为 11.2 0± 0 .2 9,与 2 0 h正常猫相比显著下降 (P<0 .0 5 )。显像研究显示正常猫纹状体 2 0 h特异性结合为 4 .83± 0 .82 ,PD模型猫为 2 .92± 0 .6 6 ,两者有显著性差异 (P<0 .0 5 )。分布研究与显像研究的结果相符。因此 ,β- CIT是一种较理想的 DAT配体 ,碘标 β- CIT的 DAT功能显     

Clearance and renal extraction of technetium-99m-L,L-ethylenedicysteine, I-131-ortho-iodohippurate and I-125-iothalamate in pigs.

99mTc-L,L-ethylenedicysteine (99mTc-EC) has been proposed as a 99mTc-labelled alternative to radio-iodinated ortho-iodohippurate (OIH) for renal imaging and evaluation of renal function. The kinetics of this new renal function agent were studied by a single-injection plasma clearance technique in pigs. 99mTc-EC, 131I-OIH and 125I-iothalamate were injected and the plasma concentration of the three tracers was followed for 240 min. Renal, hepatic and total plasma clearance were calculated. There was no difference between the renal plasma clearance of 99mTc-EC and 131I-OIH (175 +/- 9 versus 178 +/- 8 ml min-1, P = 0.43), whereas the difference between the total plasma clearance of 99mTc-EC and 131I-OIH was highly significant (268 +/- 16 versus 185 +/- 9 ml min-1, P = 0.0001). 99mTc-EC had a significant hepatic clearance of 83 +/- 10 ml min-1 whereas the hepatic clearance of 131I-OIH was negligible. Renal plasma extraction of both 99mTc-EC and 131I-OIH decreased significantly between 2 and 240 min post-injection from 0.85 to 0.45% for 99mTc-EC and from 0.93 to 0.57% for 131I-OIH. Red blood cell binding of 99mTc-EC and 131I-OIH was 6.1% and 20%, respectively. The protein binding of 99mTc-EC and 131I-OIH was 32% for both tracers. We conclude that 99mTc-EC is not a suitable tracer for measuring renal function by the single-injection plasma clearance technique in pigs. This is due to a decreasing renal extraction and a significant hepatic clearance.     

血浆NT-ProBNP在~(131)碘治疗甲亢及甲亢性心脏病中的应用

目的:探讨血浆N末端脑钠肽前体(NT-ProBNP)在131碘治疗甲亢及甲亢性心脏病(甲亢心)中的应用价值。方法:亚临床甲亢组30例,平均年龄39.4±14.2岁,甲亢组45例,平均年龄42.9±16.7岁,甲亢心组21例,平均年龄46.4±13.9岁,正常对照组37例,平均年龄41.5±11.4岁,采用门控心肌显像法评价心脏功能,血浆NT-ProBNP、游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)水平用罗氏电化学发光分析仪(Cobase601)测定。结果:甲状腺激素FT3、FT4与NT-ProBNP水平之间呈显著正相关,相关系数分别为0.505(P<0.01)和0.535(P<0.01);治疗前后的NT-ProBNP水平比较差异有显著性统计学意义(P<0.01)。结论:131碘治疗甲亢及甲亢心时,NT-ProBNP是评价疗效的有用指标。     

Radioimmunoimaging of human small cell lung carcinoma with I-131 tumor specific monoclonal antibody

In this study, an IgM monoclonal antibody (MAb600D11) directed against human small cell lung cancer (NCI-H69) was radiolabeled with iodine-131, and the biodistribution and image quality of the radiolabeled antibody was evaluated. Radiolabeling was achieved in a solid-phase system consisting of 1,3,4,6-tetrachloro-3a,6a-diphenylglycoluril. Labeling efficiencies and protein purification were accomplished using gel exclusion chromatography while radioimmunoreactivity was determined using a solid-phase radioimmunoassay procedure. The biodistribution of I-131-labeled MAbs was determined in Sprague-Dawley rats up to 7 days after injection. Highest organ concentrations were observed in liver (3.91 +/- 0.47 (SD) and 0.17 +/- 0.04 (SD) mean percent injected dose at 1-7 days after injections) and in thyroid (5.33 +/- 0.71 (SD) and 5.32 +/- 2.01 (SD) mean percent injected dose at 1-7 days after injection). Nude mice, bearing either a small cell lung tumor (NCI-H69) or a nonspecific tumor (adenocarcinoma), were injected with 400-800 microCi of I-131 labeled monoclonal antibody. Optimum tumor visualization was observed 2-4 days after injection with tumor concentrations as high as 10.4% of the initial injected dose. The results demonstrated that radioimmunoimaging of human small cell lung carcinoma was feasible with the tumor-specific IgM I-131-labeled MAb.     

Recovery of total I-131 activity within focal volumes using SPECT and 3D OSEM

We experimentally investigated the SPECT recovery of I-131 activity in multiple spheres located simultaneously at different locations within a cylindrical phantom that had an elliptical cross section. The sphere volumes ranged from 209 cc down to 4.2 cc. A Prism 3000 camera and two types of parallel-hexagonal-hole collimation were employed: high energy (HE) and ultra high energy (UHE). Using appropriately-different 3D models of the point source response function for the two types of collimation, approximately the same recovery of activity could be achieved with either collimation by 3D OSEM reconstruction. The recovery coefficient was greater with no background activity in the phantom by 0.10, on average, compared to that with background. In the HE collimation case, the activity recovery was considerably better for all volumes using 3D OSEM reconstruction than it had been in the past using 1D SAGE reconstruction. Recovery-coefficient-based correction in a simulated patient case involving spherical tumours moderately improved the activity estimates (average error reduced from 14% to 9% for UHE collimation, and from 15% to 11% for HE collimation). For a test case with HE collimation, increasing the projection-image sampling density while decreasing the image voxel size increased the recovery coefficient by 0.075 on average, and, if used in a full set of calibration measurements of recovery coefficient versus volume, might lead to further improvement in accuracy for the patient case.