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E A Deutsch

Publications and source records attributed to E A Deutsch.

11 recordsLinked to original sources
PubMed1998

Technetium-99m Q4: a prototype cationic perfusion radiotracer with myocardial washout.

Technetium-99m Q4 is derived from an existing mixed ligand myocardial tracer (99mTc-Q3) by the addition of an ester group to promote myocardial washout. Six subjects with single-vessel coronary disease documented by angiography and/or Q wave myocardial infarction documented by electrocardiography were studied with 99mTc-Q4 injection during exercise and with comparative thallium-201 tomography. Six healthy volunteers were also studied with 99mTc-Q4 imaging following injection at peak exercise. Tomographic images with 99mTc-Q4 and 201Tl each provided correct assessment of the presence or absence of coronary disease in 22 of 30 myocardial segments (73.3%). Six myocardial segments showed defect reversibility with 99mTc-Q4, whereas 14 segments showed reversibility with 201Tl, but the latter included three segments with no angiographic or electrocardiographic evidence of disease. In both normals and subjects with coronary artery disease, significant global washout of 99mTc-Q4 was observed over 4 h. For five patients with angiographic evidence of unrevascularized coronary artery stenosis, the ischemic to normal zone count ratio increased from 0. 782+/-0.107 at 45 min postexercise to 0.891+/-0.115 at 4 h postexercise (P = 0.016), suggesting occurrence of differential washout. It is concluded that addition of an ester group functionality to a previously studied mixed ligand cardiac tracer promotes global and regional myocardial tracer washout. Nevertheless, demonstration of perfusion defect reversibility with comparable frequency to that observed with 201Tl stress and reinjection images, required separate injections of 99mTc-Q4 at peak stress and at rest.

Adult↗
PubMed1993

Chemistry and biological behavior of samarium-153 and rhenium-186-labeled hydroxyapatite particles: potential radiopharmaceuticals for radiation synovectomy.

Hydroxyapatite (HA), a natural constituent of bone, was studied as a particulate carrier for beta-emitting radionuclides in radiation synovectomy. Particles were radiolabeled with 153Sm or 186Re and their in vivo safety was investigated following intra-articular injection into knees of normal rabbits and rabbits with antigen-induced arthritis (AIA). Radiolabeling efficiency was greater than 95%; in vitro studies showed minimal (< or = 1%) loss of activity from particles over a 6-day period with 153Sm-labeled HA and about 5% loss of activity over a 5-day period with 186Re-labeled HA. The total cumulative extra-articular leakage of 153Sm over 6 days was 0.28% in normal rabbits and 0.09% in AIA rabbits. Leakage of 186Re from the joint was 3.05% over a 4-day period with 80% of extra-articular activity found in the urine. Histopathological evaluation of treated knees showed that HA particles are distributed throughout the synovium, embedded in the synovial fat pad. The ease and efficiency with which this HA carrier is labeled, coupled with observed extremely low leakage rates from the joint, make radiolabeled HA particles an attractive candidate as a radiation synovectomy agent for evaluation in rheumatoid arthritis patients.

Animals↗
PubMed1993

Potential gallium-68 tracers for imaging the heart with PET: evaluation of four gallium complexes with functionalized tripodal tris(salicylaldimine) ligands.

Gallium-67 and 68Ga complexes have been synthesized with tripodal hexadentate salicylaldimine ligands derived from 1,1,1-tris(salicylaldiminomethyl)ethane, sal3tame. The four ligands evaluated contained alkoxy substituents (n-BuO-, iso-BuO-, sec-BuO-, and n-PrO-) on the terminal ethane carbon of the ligand backbone. In the case of the n-PrO-derivative, the tris(salicylaldimine) ligand was additionally substituted with methoxy groups in the 5-position of the aromatic rings. The 67Ga and 68Ga-complexes of these ligands were prepared by ligand exchange from 67Ga- or 68Ga-acetylacetonate in ethanol. The nonradioactive Ga[(sal)3tame-O-iso-Bu] complex was similarly prepared and shown by x-ray crystallography to exhibit the expected pseudo-octahedral N3O3(3-) coordination sphere about the Ga3+ center. These Ga-radiotracers are highly lipophilic, as demonstrated by their octanol/water partition coefficients. Log P values of 3.1, 3.1, 2.6, and 2.5 were found for the [(sal)3tame-O-iso-Bu], [(sal)3tame-O-n-Bu], [(sal)3tame-O-sec-Bu], and [(5-MeOsal)3tame-O-n-Pr] complexes, respectively. Following intravenous injection into rats, these complexes are rapidly cleared from the blood and exhibit significant myocardial uptake. At 1 min postinjection, 2.4%, 2.0%, 2.1% and 1.1% of the injected dose was found in the heart for the iso-BuO, n-BuO, sec-BuO, and n-PrO complexes, respectively, dropping to 1.0%, 0.8%, 0.8%, and 0.7% at 5 min. The corresponding heart-to-blood ratios are quite high: 17 +/- 3, 14 +/- 2, 12 +/- 2 and 3.5 +/- 0.4 at 1 min and 14 +/- 4, 10 +/- 1, 10 +/- 1 and 3.2 +/- 0.1 at 5 min postinjection. High quality myocardial images were obtained with PET in a normal dog using data collected from 2 to 10 min following intravenous injection of 68Ga[(sal)3tame-O-iso-Bu].

Animals↗
PubMed1992

Rhenium-186 hydroxyethylidene diphosphonate for the treatment of painful osseous metastases.

Rhenium-186 (tin)hydroxyethylidene diphosphonate (HEDP) is a new radiopharmaceutical that localizes in skeletal metastases in patients with advanced cancer. A single intravenous administration of approximately 34 mCi (1,258 MBq) resulted in significant improvement in pain in 33 of 43 evaluable patients (77%) following the initial injection, and in 7 of 14 evaluable patients (50%) following a second treatment. Patients responding to treatment experienced an average decrease in pain of about 60%, with one in five treatments resulting in a complete resolution of pain. The only adverse clinical reaction was the occurrence after about 10% of the administered doses of a mild, transient increase in pain within a few days following injection. Statistically significant but clinically unimportant decreases in total white blood cell counts and total platelet counts were observed within the first 8 weeks following the injection; no other toxicity was apparent. Rhenium-186(Sn)HEDP is a useful new compound for the palliation of painful skeletal metastases.

Bone Neoplasms↗
PubMed1990

Re-186(Sn) HEDP for treatment of painful osseous metastases: initial clinical experience in 20 patients with hormone-resistant prostate cancer.

Rhenium-186(tin) hydroxyethylidene diphosphonate (HEDP) is a new radiopharmaceutical that localizes in areas of osseous metastases in a manner similar to that of standard bone-scanning agents. It also emits beta particles with sufficient energy to be therapeutically useful. A single intravenous injection of about 33 mCi (1,221 MBq) was given to each of 20 elderly patients with advanced skeletal metastases from hormonally resistant prostate cancer. Prompt, significant relief of pain occurred 80% of the time with no significant side effects and only minimal, transient marrow toxicity. Re-186(Sn) HEDP appears to be a useful new agent for the palliation of painful osseous metastases in prostate cancer.

Adenocarcinoma↗
PubMed1988

Re-186(Sn) HEDP for treatment of multiple metastatic foci in bone: human biodistribution and dosimetric studies.

Investigation of the biodistribution of subtherapeutic amounts of a new, chromatographically purified rhenium-186(tin) hydroxyethylidene diphosphonate radiopharmaceutical have been completed in five patients with metastatic carcinoma to bone. The new agent localizes in metastatic foci in bone in the same manner as do standard technetium-99m diphosphonate bone-scanning agents and appears able to deliver therapeutic radiation doses of thousands of rads (tens of grays) to these metastatic foci while limiting the total red marrow dose to less than 75 rad (0.75 Gy). The simultaneous treatment of multiple metastatic foci in bone appears feasible with this new agent.

Adult↗
PubMed1984

Myocardial scintigraphy with 99mTc-tris-DMPE in man.

Cardiac scintigraphy was performed in six patients with a documented previous myocardial infarction, in one patient with mitral regurgitation, and in four healthy volunteers following administration of 99mTc-tris-DMPE. An intense early blood pool phase permitted gated blood pool scintigraphy and left ventricular ejection fraction calculation. A myocardial phase 12-14 h later permitted myocardial perfusion imaging. The rest myocardial perfusion image quality with 99mTc-tris-DMPE appeared to be superior to the resting image quality obtained with 99mTc-dichloro-DMPE but was inferior to the resting image quality obtained with 201Tl.

Aged↗
PubMed1984

186Re-HEDP: a potential therapeutic bone agent.

A lyophilized kit preparation of HEDP for labelling with 186Re has been developed as a potential bone agent useful for both diagnosis and therapy. High pressure liquid chromatographic analysis showed that the 186Re-HEDP is a mixture of several components. Preliminary in vivo studies in several animal species showed that both the 186Re-HEDP mixture and the HPLC-purified main component are bone-seeking agents with slow blood and soft-tissue clearance rates. HPLC purification slightly improved the quality of the image. In mice and rats with trauma-induced osteogenetic activity in one leg, the bone uptake of the traumatized leg was 1.7-1.9 times higher than of the normal leg. The lesion-to-normal bone ratio was 4-5.4.

Animals↗
PubMed1983

Myocardial perfusion imaging with 99mTc-DMPE in man.

Technetium-99m DMPE (99mTc-DMPE) is a newly synthesized myocardial perfusion imaging agent that shows intense myocardial accumulation in the dog. In the present study, dosimetry and potential clinical usefulness of this agent were assessed in four human subjects. Absorbed radiation doses were low, with the highest doses consisting of 200 mrad/mCi (54 microGy/MBq) to the gallbladder and 160 mrad/mCi (43 microGy/MBq) to the liver. No evidence of clinical toxicity was found. Technetium-99m DMPE did image the myocardium, but the ratio of target to nontarget activity was less favorable than that observed in the dog. Intense hepatic 99mTc-DMPE activity interfered with clinical imaging of the cardiac apex in two of the four subjects. We conclude that the prototype radiopharmaceutical, 99mTc-DMPE, is capable of myocardial perfusion imaging in man but the planar myocardial images produced are of inferior quality compared with 201Tl myocardial images. Further work is justified to develop related compounds to overcome the clinical limitations described.

Adult↗
PubMedDate not supplied

Biokinetics and dosimetry analysis in healthy volunteers for a two-injection (rest-stress) protocol of the myocardial perfusion imaging agent technetium 99m-labeled Q3.

BACKGROUND: Trans (N,N'-ethylene bis(acetylacetoneimine)) bis(tris(3-methoxy-1-propyl) phosphine) 99mTc(III) (99mTc-Q3) has been developed for myocardial perfusion imaging. Biokinetic studies and dosimetry analysis have been completed for six healthy volunteers. METHODS AND RESULTS: The same-day two-injection protocol involved (1) an average rest injection of 241 MBq of 99mTc-Q3 followed by myocardial single-photon emission computed tomography (SPECT) at 15.0 minutes and a whole body (WB) scan at 1.5 hours; and (2) an average stress injection during treadmill exercise of 744 MBq of 99mTc-Q3 at 2.4 hours (postrest injection) followed by myocardial SPECT and additional WB scans at 1.5, 3.5, 6.5, and 21 hours poststress injection. Total urine was collected over 24 hours. Absolute organ activities were determined by conjugate counting methods. The two-injection data were simplified to a one-injection equivalent data set to facilitate dosimetry analysis. Decay corrected average percentage uptake values, plus or minus one standard deviation, for the myocardium were 1.4% +/- 0.2% at approximately 1.5 hours for both the postrest and poststress injections. The average biologic half-time for the myocardium was 26.4 hours. The highest organ uptake values included the gallbladder with 5.5% +/- 1.9% and the liver with 4.1% +/- 1.0% at the 1.5 hours poststress scan time. The sum of all gastrointestinal (GI) tract components was 18.8% +/- 9.4% at approximately 6.5 hours poststress injection (before any fecal elimination). The total 24 hour urine clearance was 17.1% +/- 2.4%. The gallbladder wall and upper large intestine wall received the highest doses at 0.024 and 0.023 mGy/MBq, respectively. CONCLUSION: The effective dose equivalent is estimated to be 0.01 mSv/MBq, which for an administration of 1110 MBq (30 mCi) is less than half that of a standard imaging protocol using 111 MBq (3 mCi) of 201Tl, and comparable to the published estimates for 99mTc-labeled sestamibi and 99mTc-labeled tetrofosmin (also normalized to 1110 MBq of administered activity). The 99mTc-Q3 exhibits myocardium uptake similar to that for these other two 99mTc agents.

Adult↗