99mTc-枸橼酸盐显像鉴别骨转移癌与良性退行性骨病变

目的 探讨99mTc-枸橼酸盐(99mTc-citrate)显像在骨转移癌与良性退行性骨病鉴别诊断中的价值.方法 对99mTc-亚甲基二膦酸盐(99mTc-MDP)骨显像阳性患者39例(92个病灶)在显像后的2～7 d内行99mTc-citrate显像,并分别进行定性及半定量分析,所有患者的临床诊断均经病理学、影像学、临床随访等证实.结果 定性分析:23例(48个病灶)骨转移癌患者的99mTc-citrate显像示72.92%病灶(35/48)呈异常浓聚;16例良性退行性骨病变者99mTc-citrate显像示88.64%病灶(39/44)无异常浓聚.半定量分析:99mTc-citrate显像示48个骨转移灶的病灶与健侧放射性摄取比(RUR)=1.47±0.42,44个良性退行性骨病灶RUR=1.09±0.38,两者相比差异有显著性(t=2.887,P＜0.01);而99mTc-MDP显像示48个骨转移灶RUR=1.96±0.25,44个良性退行性骨病灶RUR=1.87±0.21,差异无显著性(t=1.178,P＞0.20).结论 对99mTc-MDP骨显像阳性患者,99mTc-citrate显像在鉴别骨转移癌和良性退行性骨病中具有一定价值.     

Gastrointestinal scintigraphy with 99mTc-DTPA labeled tablets in fed and fasting subjects

The in vitro and in vivo dissolution of a sustained release theophylline formulation labeled with ^99mTc-diethyltriaminepentaacetic acid (DTPA) has been monitored in six subjects with a scintillation camera. The study was performed in fasting conditions and was repeated after ingestion of a standardized meal. Results showed that the presence of food in the stomach dramatically increased the oesoduodenal transit time of the tablet (74±27 min vs 352±77 min, P<0.001) but did not modify the biodisponibility of theophylline. This study is another example when scintigraphy can be of definite value in pharmacokinetics.     

Gastrointestinal scintigraphy with 99mTc-DTPA labeled tablets in fed and fasting subjects

The in vitro and in vivo dissolution of a sustained release theophylline formulation labeled with 99mTc-diethyltriaminepentaacetic acid (DTPA) has been monitored in six subjects with a scintillation camera. The study was performed in fasting conditions and was repeated after ingestion of a standardized meal. Results showed that the presence of food in the stomach dramatically increased the oesoduodenal transit time of the tablet (74 +/- 27 min vs 352 +/- 77 min, P less than 0.001) but did not modify the biodisponibility of theophylline. This study is another example when scintigraphy can be of definite value in pharmacokinetics.     

Measurement of glomerular filtration rate with 99mTc-DTPA: A comparison of gamma camera methods

A comparison has been made between three gamma camera methods for estimation of glomerular filtration rate (GFR) using ^99mTc-DTPA in a group of 27 patients with widely different renal function. Plasma clearance of ^99mTc-DTPA by multiple blood sampling was used as the reference. Percentage uptake of chelate in the bladder and kidneys at 20 min after injection gave the lowest standard error of 8.0 ml/min. Techniques using early uptake of isotope in the kidneys at 2 min after injection gave less accurate estimates. Correction for the vascular activity in the renal region of interest improved the results for the 2 min uptake technique. Gamma camera techniques provide rapid estimates of GFR which are less accurate than those obtained by plasma clearance of labelled chelate.     

Clinical experience with 99mTc-MAG3, mercaptoacetyltriglycine, and a comparison with 99mTc-DTPA

The preparation, application and clinical usage of 99mTc-mercaptoacetyltriglycine, MAG3, a tubular secreted compound, is described in the first 225 patients in a phase III study. Image quality, relative renal function, and renal transit times were compared with a 4 fold greater administered activity of 99mTc-DTPA in 11 patients. Correlation coefficients of 0.94 for relative function, 0.83 for parenchymal transit time index and 0.82 for whole kidney transit time index were found. Frusemide responses were similar. 99mTc-MAG3 is an efficacious radiopharmaceutical for routine renal radionuclide studies, giving excellent image quality in patients with hypertension, poor renal function, obstructive nephropathy or a renal transplant.     

Relationship between severity of clinical symptoms and delay in gastric emptying in chronic gastritis; studied with 99mTc-DTPA scintigraphy

The gastric emptying time is studied with ^99mTC-DTPA-labeled mixed meal in 18 patients with chronic gastritis, all confirmed by endoscopic examination and biopsy. Emptying was slow in all such patients, but the intensity of symptomatology showed no correlation with gastric emptying half time.     

Relationship between severity of clinical symptoms and delay in gastric emptying in chronic gastritis; studied with 99mTc-DTPA scintigraphy

The gastric emptying time is studied with 99mTC-DTPA-labeled mixed meal in 18 patients with chronic gastritis, all confirmed by endoscopic examination and biopsy. Emptying was slow in all such patients, but the intensity of symptomatology showed no correlation with gastric emptying half time.     

SPECT using 99mTc-DTPA for the assessment of disease activity in Graves' ophthalmopathy: a comparison with the results from MRI

Currently available methods for the estimation of disease activity in the orbits of patients with Graves' ophthalmopathy (GO) have the disadvantages of being either expensive or time consuming. The aim of this study was to develop a quick, reliable method using Tc labelled diethylenetriaminepentaacetic acid (DTPA) and four-headed single photon emission computed tomography (SPECT) for this purpose. The theoretical basis of the method is that the high capillarization and oedema in the orbit may be reflected on Tc-DTPA images in GO. SPECT data of 28 orbits of 14 patients with GO were compared with magnetic resonance imaging (MRI) T2 relaxation time scores. Based on the number of 'active' muscles with T2 relaxation times of more than 70 ms in a given orbit, an MRI score of 0 (no active muscle) to 4 (all rectus muscles active) was assigned to the orbit. With MRI, 18 orbits were inactive, and 10 were active. Thirty minutes after the intravenous administration of 7 MBq.kg Tc-DTPA, 128 projections were acquired by a four-headed SPECT. On the sum of six transaxial slices containing the entire bulbar region of the skull, a triangle-like region of interest (ROI) was drawn (OR ROI). This ROI was 'slipped' to the right temporal region of the brain as reference site (B ROI). The count ratios of OR/B were calculated and compared to MRI score values. In the group of 18 inactive orbits (an MRI score of zero on both sides), in the transaxial plane, the mean OR/B value was 6.4+/-1.17, and in the group of 10 active orbits (an MRI score of 1-3) 8.30+/-2.08, the difference being significant (P <0.05). Tc-DTPA orbital SPECT is a promising method for the estimation of disease activity in the orbits of patients with Graves' ophthalmopathy.     

99mTc-DTPA and 99mTc-rhenium sulfur aerosol compared as adjuncts to perfusion scintigraphy in patients with suspected pulmonary embolism

Two radiopharmaceuticals, ^99mTc-DTPA (D) and ^99mTc-rhenium sulfur (R) were evaluated with a nebulizer delivering submicronic particles. Seventy-seven patients were examined (42 D, 35 R). For all patients, the examination began with a ventilation study. Immediately after the last ventilation view, ^99mTc MAA was injected. Aerosol performance was assessed in 37 D and 17 R. Nebulization yield was 8.98% for D and 9.31% for R. A lung clearance study was performed in 12 patients for D and in 12 different patients for R. The lung clearance was 0.22%/min for R and 2.35%/min for D. The quality of ventilation and the quantification of bronchial and gastric activity were evaluated; the difference between the two groups was not statistically significant. It may be concluded that radioaerosols allow good quality images to be obtained. The yield of the nebulizer is adequate, so that nebulization of 20 mCi delivers approximately 2 mCi of aerosol activity to the lung. When pulmonary embolism is being investigated, R, due to its slower lung clearance, would appear to be preferable to D for patients suspected of increased bronchoalveolar permeability, especially if the time between nebulization and recording is greater than 10 min.     

99mTc-DTPA and 99mTc-rhenium sulfur aerosol compared as adjuncts to perfusion scintigraphy in patients with suspected pulmonary embolism

Two radiopharmaceuticals, 99mTc-DTPA (D) and 99mTc-rhenium sulfur (R), were evaluated with a nebulizer delivering submicronic particles. Seventy-seven patients were examined (42 D, 35 R). For all patients, the examination began with a ventilation study. Immediately after the last ventilation view, 99mTc MAA was injected. Aerosol performance was assessed in 37 D and 17 R. Nebulization yield was 8.98% for D and 9.31% for R. A lung clearance study was performed in 12 patients for D and in 12 different patients for R. The lung clearance was 0.22%/min for R and 2.35%/min for D. The quality of ventilation and the quantification of bronchial and gastric activity were evaluated; the difference between the two groups was not statistically significant. It may be concluded that radioaerosols allow good quality images to be obtained. The yield of the nebulizer is adequate, so that nebulization of 20 mCi delivers approximately 2 mCi of aerosol activity to the lung. When pulmonary embolism is being investigated, R, due to its slower lung clearance, would appear to be preferable to D for patients suspected of increased bronchoalveolar permeability, especially if the time between nebulization and recording is greater than 10 min.     

Clinical comparison of bone scintigraphy with 99Tcm-DPD, 99Tcm-HDP and 99Tcm-MDP

The bone-imaging agents MDP, DPD and HDP were compared radiochemically (only minor differences were found) in 12 patients with prostatic and 12 patients with breast carcinoma. Each patient received both MDP and either DPD or HDP. The scintigraphic examinations were compared visually and quantitatively. The uptake ratio normal bone/soft tissue was higher for DPD and HDP than for MDP. The ratio pathologic bone/normal bone was highest for MDP, particularly for prostatic carcinoma. The differences in this ratio for breast carcinoma were in general non-significant. The observed differences were minor and of little practical importance.     

Measurement of glomerular filtration rate with 99mTc-DTPA: a comparison of gamma camera methods

A comparison has been made between three gamma camera methods for estimation of glomerular filtration rate (GFR) using 99mTc-DTPA in a group of 27 patients with widely different renal function. Plasma clearance of 99mTc-DTPA by multiple blood sampling was used as the reference. Percentage uptake of chelate in the bladder and kidneys at 20 min after injection gave the lowest standard error of 8.0 ml/min. Techniques using early uptake of isotope in the kidneys at 2 min after injection gave less accurate estimates. Correction for the vascular activity in the renal region of interest improved the results for the 2 min uptake technique. Gamma camera techniques provide rapid estimates of GFR which are less accurate than those obtained by plasma clearance of labelled chelate.     

The value of99mTc-DTPA renal scintigraphy in the evaluation of post-traumatic abdominal fluid collection

A patient with a post-traumatic retroperitoneal urinoma is presented. On admission, there was a clinical suspicion of retroperitoneal hematoma and ultrasonography (US) was performed which showed a hypoechoic fluid collection suggesting retroperitoneal hematoma. In order to determine the nature of the fluid, radionuclide angiography and renal scan were performed successively with 99mTc-DTPA. Demonstration of urinary leakage into the mass in the delayed renal scintigraphic images suggested a urinoma. At laparotomy, total transection of the left ureter in the uretero-pelvic region was found and the diagnosis of urinoma was confirmed.     

The scintigraphy of sacroiliac joints. A comparison of 99mTc-DPD and 99mTc-MDP

The accumulation of 99mTc-methylene diphosphonate (99mTc-MDP) and 99mTc-dicarboxypropane diphosphonate (99mTc-DPD) in sacroiliac (si) joints was evaluated as a function of imaging time in 22 control patients and 5 patients with sacroiliitis. The controls were injected with either 99mTc-DPD or 99mTc-MDP (12 and 10 patients, respectively) and the patients with sacroiliitis with both agents within 5 days. Both the anterior and posterior views of the si joints were taken. The sacroiliac joint-to-sacrum (SI/S) ratio was calculated with the region of interest method. No statistically significant differences between these bone-seeking agents were found in the SI/S ratios of the control or the diseased patients. A clear overlap of indices (mean +/- SD) was found between the control patients and the patients with sacroiliitis. When the inflamed si joint was divided into three small adjacent areas and the SI/S ratios calculated for these areas, a statistically significant (P less than 0.001) increase in the SI/S ratio was noticed when compared with the SI/S ratio of the whole joint. Comparison of control patients and patients with sacroiliitis showed the most significant differences in the anterior views as well as in the P value: P less than 0.001 in all patients injected with 99mTc-DPD and in most patients injected with 99mTc-MDP. In the posterior views, the significance was less marked. In every case, the inflamed part of the si joint was visible in the anterior views. The background subtraction had the greatest effect on the SI/S ratio of anterior images, but in the posterior views no significance was found.(ABSTRACT TRUNCATED AT 250 WORDS)     

Tc-99m HMPAO scintigraphy in amiodarone-induced acute lung toxicity: comparison with Tc-99m DTPA inhalation scintigraphy

PURPOSE: This case demonstrates the use of Tc-99m HMPAO scintigraphy in amiodarone (AD)-induced lung toxicity. The aim of this presentation is also to discuss different scintigraphic modalities in the diagnosis and follow up in AD-induced lung toxicity. MATERIALS AND METHODS: A 77-year-old man, with a suspicious AD-induced acute lung toxicity, underwent Tc-99m DTPA aerosol inhalation scintigraphy and Tc-99m HMPAO scintigraphy. RESULTS: Rapid alveolar clearance of Tc-99m DTPA was found during AD therapy and increased lung uptake of Tc-99m HMPAO was also demonstrated. These findings supported the diagnosis AD lung toxicity. After cessation of therapy, Tc-99m DTPA alveolar clearance was decreased. Although there was some decrease in L/H and L/B ratios of Tc-99m HMPAO after 3 weeks of stopping therapy, Tc-99m HMPAO uptake in the lungs was still continued. This finding may be the result of ongoing pulmonary inflammation as a result of the long half-life of AD. CONCLUSION: Compared with Tc-99m DTPA aerosol inhalation scintigraphy, Tc-99m HMPAO scintigraphy may have a role in the diagnosis of AD lung toxicity. Nevertheless, there is a need for longitudinal studies investigating patients under AD therapy using follow-up Tc-9m HMPAO scintigraphy.     

Mismatch between 99mTc-DTPA aerosol and 81mKr lung ventilation scintigraphy: a pitfall of radionuclide imaging

Pulmonary ventilation and perfusion scintigraphies were performed using 99mTc-MAA, 81mKr, and 99mTc-DTPA aerosol in a patient with asthma. Lung perfusion scintigraphy and 99mTc-DTPA aerosol scintigraphy showed multiple matching defects, however, 81mKr ventilation scintigraphy showed mismatch with lung perfusion scintigraphy. A pitfall of this examination was discussed.