A micro-autoradiographical study of the localization of 99mTc(Sn)-MDP and 99mTc-MDP in undecalcified bone sections

The localization of 99mTc(Sn)-MDP in bone tissue was compared with 99mTc-MDP by means of microautoradiography of undecalcified bone sections. Sections of good histological quality were obtained by a rapid embedding method in methylmethacrylate. No differences were found in the localization of these radiopharmaceuticals in fetal rat calvariae after incubation in vitro or in rat femora after administration in vivo. In the incubation experiment, hydrolyzed 99mTc was formed. The uptake was high in areas of new bone formation. No uptake was seen in cells or in resorbing areas. In compact bone 99mTc(Sn)-MDP was predominantly taken up in the vicinity of blood vessels.     

Fast diagnosis (6 h) of clinically silent pyonephrosis by combined use of 99mTc-MDP and 67Ga citrate

A fast diagnosis (6 h) of clinically latent pyonephrosis by combined use of ^99mTc-MDP and ⁶⁷Ga-citrate is reported. This technique combines the potential early detection of focal infectious processes by ⁶⁷Ga and the high-pulse separation possibility of multiple isotopes. A brief prospective study (6 months) showed the interest of this technique: in six cases focal bone and/or joint infections were found three of which were absolutely latent clinically.     

Fast Diagnosis (6h) of clinically silent pyonephrosis by combined use of 99mTc-MDP and 67Ga citrate

A fast diagnosis (6h) of clinically latent pyonephrosis by combined use of 99mTc-MDP and 67Ga-citrate is reported. This technique combines the potential early detection of focal infectious processes by 67Ga and the "high-pulse" separation possibility of multiple isotopes. A brief prospective study (6 months) showed the interest of this technique: in six cases focal bone and/or joint infections were found three of which were absolutely latent clinically.     

Assessment of hepatic blood flow by PET with 15O water: correlation between per-rectal portal scintigraphy with 99Tc(m)-pertechnetate and scintigraphy with 99Tc(m)-GSA

We performed positron emission tomography with 15O water (H2(15)O) to measure hepatic arterial and portal blood flow. In addition, portal haemodynamics and hepatic functional reserve were measured by per-rectal portal scintigraphy and scintigraphy with galactosyl human serum albumin, respectively. We studied 15 patients who had cirrhosis of the liver with underlying viral infection. After the intravenous injection of H2(15)O, positron emission tomography was performed. Blood samples were obtained after beginning the emission scan. The blood samples and positron emission tomographic images were analysed to calculate the radioactivity in the blood and liver. One-compartment model analysis was used to estimate hepatic arterial and portal blood flow. Computer acquisition of gamma-camera data was started just before the injection of 99Tc(m)-galactosyl human serum albumin. A receptor index and an index of blood clearance were calculated on the basis of the radioactivity of the liver and heart. A 99Tc(m)-pertechnetate solution was instilled into the rectum; serial scintigrams were performed and radioactivity curves for the liver and heart were recorded sequentially. A per-rectal portal shunt index was calculated from the curves. Median portal blood flow was 80 ml x 100 g(-1) x min(-1), median hepatic arterial blood flow was 56 ml x 100 g(-1) x min(-1), and median total hepatic blood flow was 138 ml x 100 g(-1) x min(-1) in patients with cirrhosis. The correlations between portal blood flow and the Child-Turcotte classification score, portal shunt index and receptor index were all significant. Our results show that hepatic arterial and portal blood flow can be measured by positron emission tomography with H2(15)O non-invasively and physiologically. This technique may be useful in pathophysiological studies of liver disease.     

Comparison of (18)F-FDG PET/CT and (99 m)Tc-MDP bone scintigraphy for detection of bone metastasis in osteosarcoma

Objective

We compared the diagnostic performance of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) and (99 m)Tc-methylene diphosphonate bone scintigraphy (BS) for the detection of bone metastasis in osteosarcoma.

Materials and methods

We retrospectively reviewed 206 patients with stage II–IV osteosarcoma treated with surgery and chemotherapy as well as at least one paired PET/CT and BS scan (defined as an examination). PET/CT and BS images were interpreted separately. When analyzing the diagnostic yield of a combination of PET/CT and BS (PET/CT+BS), an examination was considered positive if either PET/CT or BS scored positive. The final diagnosis was obtained from histological findings or clinical follow-up with imaging studies for at least 6 months. Diagnostic performances of PET/CT, BS, and their combinations were calculated.

Results

Out of 833 examinations in 206 patients, 55 with 101 lesions in 38 patients were confirmed as bone metastases. The sensitivity, specificity, and diagnostic accuracy were 95, 98, and 98 %, respectively, for PET/CT; 76, 97, and 96 %, respectively, for BS; and 100, 96, and 97 %, respectively, for PET/CT+BS in an examination-based analysis. Lesion-based analysis demonstrated that the sensitivity of PET/CT+BS (100 %) was significantly higher than that of PET/CT (92 %) or BS (74 %) alone. BS detected significantly less bone metastases in the growth plate region than outside the growth plate region (22 vs. 77 %).

Conclusions

PET/CT is more sensitive and accurate than BS for diagnosing bone metastases in osteosarcoma. The combined use of PET/CT and BS improves sensitivity.     

Relation between serum PAP (prostate acid phosphatase) and bone scintigraphy in prostatic cancer]

Seventy-seven patients with prostatic cancer were treated at our department in the last 5 years. Of these patients 30 cases were followed by bone scintigraphy and serum PAP. In 27 follow-up scintigraphy procedures changes of bone scintigraphy corresponded to changes in serum PAP levels Changes of PAP levels did not always correspond to changes of scintigraphy, but almost all cases in which the level of PAP increased in a short period showed progression of bone metastasis. A 3-month interval between bone scintigraphy procedure in stage D2 prostatic cancer patients is generally recommended. However, we think that in prostatic cancer patients follow-up bone scintigraphy at regular short intervals is unnecessary if there is no change in serum PAP levels, symptoms or physical condition. Bone scintigraphy should be performed when the tumor marker changes rapidly or when any physical symptom appears.     

The contraction fraction (CF) in myocardial studies with technetium-99m-isonitrile (MIBI)--correlations with radionuclide ventriculography and infarct size measured by SPECT

Criteria for the detection of coronary artery disease in nuclear cardiology include visualization of perfusion defects and functional impairment of contraction. The purpose of this study is to combine both methods in one procedure with the new myocardial perfusion tracer, 99mTc-methoxy-isobutyl-isonitril (MIBI), reducing time and radiation burden to the patient. Following an uncomplicated recovery, ten patients with first myocardial infarction participated in this study. Radionuclide ventriculography (RNV) was performed at rest and during exercise. Within 2-3 days, 370 MBq 99mTc-MIBI were injected and SPECT acquisition commenced 1 h later. Data processing included a scar image in polar coordinates. Areas of significantly reduced tracer uptake were expressed as a percentage of the total myocardial area. Directly following SPECT, resting and maximum exercise gated planar LAO images were recorded and the contraction was quantified. The concept of the contraction fraction (CF) rested on the end systolic change in count distribution: their increase in density and their centripetal concentration. For comparison, geometrical inner edge detection techniques were also applied. All algorithms for describing an EF equivalent were verified by computer simulations, showing a perfect correlation over a wide range of preset EFs. When applied to the patient studies only the non geometric methods revealed a good correlation with the ejection fraction (EF) obtained by RNV, and with the infarct size measured by SPECT.(ABSTRACT TRUNCATED AT 250 WORDS)     

Myocardial washout rate of resting 99mTc-Sestamibi (MIBI) uptake to differentiate between normal perfusion and severe three-vessel coronary artery disease documented with invasive coronary angiography

Objectives

Patients with severe coronary artery disease (CAD) may present impaired mitochondrial function to enhance ^99mTc-sestamibi (MIBI) washout from ischemic myocardium. In this study, we aimed to study the MIBI washout rate (WR) between patients with three-vessel CAD (3V-CAD) confirmed by invasive coronary angiography and healthy normal volunteers (HNV) to evaluate the potential utility of MIBI WR to differentiate between these two populations and to stratify the CAD severity.

Methods

Ten HNV (male = 5, age = 56 ± 10 years) and eight 3V-CAD patients (male = 4, age = 62 ± 8 years) with 3V lumen stenosis ≥50 % were enrolled for this study. Each study subject had a resting MIBI perfusion scan at 90 min and a repeated scan at 4 h post the MIBI injection. Global WR (GWR) and regional WR (RWR) were quantified with the percentage difference of decay-corrected polar maps obtained from the two scans and compared between the HNV and 3V-CAD groups. For the 3V-CAD group, the severity of CAD was assessed with CAD severity scores (CADSS) utilizing degree and location of obstructive lesions (stenosis ≥50 %) for quantification and compared with WR to evaluate the correlation between these two variables.

Results

Significantly higher GWR was observed in the 3V-CAD (21.1 ± 4.6 %) group than the HNV group (9.5 ± 4.9 %) (p < 0.001). RWR values in left anterior descending (LAD), right coronary artery (RCA) and left circumflex (LCX) in the 3V-CAD group were also higher than those of the HNV group (LAD 20.7 ± 5.9 vs 9.4 ± 5.6, p < 0.001; RCA 21.3 ± 4.8 vs 9.2 ± 5.8, p < 0.001; LCX 20.5 ± 7.2 vs 10.1 ± 4.4, p = 0.002). Additionally, the linear correlation of GWR and total CADSS for the whole myocardium was strong and statistically significant (y = 0.86x ? 1.12, r ² = 0.73, p = 0.006).

Conclusion

Patients with impaired mitochondrial function due to 3V-CAD had consistently higher global and regional rest ^99mTc-sestamibi washout rates than those of healthy normal volunteers. The global rest ^99mTc-sestamibi washout rate is a sensitive indicator to stratify the severity of 3V-CAD and to differentiate between severe 3V-CAD and normal perfusion populations.     

Quantitative bone matrix density measurement by water‐ and fat‐suppressed proton projection MRI (WASPI) with polymer calibration phantoms

The density of the organic matrix of bone substance is a critical parameter necessary to clinically evaluate and distinguish structural and metabolic pathological conditions such as osteomalacia in adults and rickets in growing children. Water‐ and fat‐suppressed proton projection MRI (WASPI) was developed as a noninvasive means to obtain this information. In this study, a density calibration phantom was developed to convert WASPI intensity to true bone matrix density. The phantom contained a specifically designed poly(ethylene oxide)/poly(methyl methacrylate) (PEO/PMMA) blend, whose MRI properties (T₁, T₂, and resonance linewidth) were similar to those of solid bone matrix (collagen, tightly bound water, and other immobile molecules), minimizing the need to correct for differences in T₁ and/or T₂ relaxation between the phantom and the subject. Cortical and trabecular porcine bone specimens were imaged using WASPI with the calibration phantom in the field of view (FOV) as a stable intensity reference. Gravimetric and amino acid analyses were carried out on the same specimens after WASPI, and the chemical results were found to be highly correlated (r² = 0.98 and 0.95, respectively) to the WASPI intensity. By this procedure the WASPI intensity can be used to obtain the true bone matrix mass density in g cm^–3. Magn Reson Med 60:1433–1443, 2008. © 2008 Wiley‐Liss, Inc.     

IL-3和IL-6单独和联合IL-1, G-CSF, GM-CSF对小鼠异基因骨髓移植后血小板计数的影响

我们在一个小鼠异基因骨髓移植模型中检测ＩＬ－３和ＩＬ－６单独和联合ＩＬ－１，Ｇ－ＣＳＦ，ＧＭ－ＣＳＦ对血小板恢复的影响。当单独给予时，与正常对照小鼠比较（２１６×１０９／Ｌ），ＩＬ－６和Ｇ－ＣＳＦ分别显著增加移植后６天血小板计数（３１２×１０９／Ｌ，Ｐ＜０．０５；３０９×１０９／Ｌ，Ｐ＜０．０１）。ＩＬ－３单独给予血小板计数为３０３×１０９／Ｌ，（Ｐ＜０．０５）。在联合给予中，只有ＩＬ－３＋Ｇ－ＣＳＦ显著增加移植后６天血小板计数（３２８×１０９／Ｌ，Ｐ＜０．０５）。