Quantitation in Dextrocardia on myocardial perfusion imaging: how to perform quantitative analysis using Cedars-Sinai software

Dextrocardia, although a rare cardiac abnormality, carries the same risk for cardiac events as other people. SPECT Myocardial perfusion imaging is a potentially helpful diagnostic tool in patients with dextrocardia. Because of swapping of lateral and septal walls on SPECT slices, although visual analysis is possible, quantitation is substantially limited. Here, we introduce a simple practical method to make quantitative analysis feasible and accurate.Dextrocardia, although a rare cardiac abnormality, carries the same risk for cardiac events as other people. SPECT Myocardial perfusion imaging is a potentially helpful diagnostic tool in patients with dextrocardia. Due to swapping of lateral and septal walls on SPECT slices, although visual analysis is possible, quantitation is substantially limited. Here, we introduce a simple practical method to make quantitative analysis feasible and accurate.

ONE SIZE DOES NOT FIT ALL: THE MERIT OF ABSORBED DOSES TO THE BLOOD IN 131I THERAPY FOR DIFFERENTIATED THYROID CARCINOMA

Abstract—The amount of 131I necessary for successful ablation in patients with differentiated thyroid cancer (DTC) is still subject to debate. This study investigates the relationship of the absorbed dose of radiation to the blood while administering 131I activity with several other parameters in DTC patients. This prospective study included 90 DTC patients who were classified into three groups according to their level of dosage: 3.7 GBq (38.9%), 5.55 GBq (55.6%), and 7.4 GBq (5.5%). Blood dosimetry of treated patients was performed using external whole-body counting with a Geiger Muller dosimeter located 2 m away from the patients. Dose rate was measured at 2, 4, 5, 24, and 48 h after the administration of radioiodine. Based on the results of whole-body dose rate measurements, 48 h after administration of 3.7, 5.55, and 7.4 GBq of radioiodine, absorbed doses to patients’ blood were estimated at 0.49 ± 0.12, 0.71 ± 0.21, and 0.76 ± 0.11 Gy, respectively. Increasing radioiodine dosage from 3.7 GBq to 5.55 GBq significantly increased blood dose, while there was no significant difference in blood dose between radioiodine dosages of 5.55 GBq and 7.4 GBq. The absorbed dose to the blood was significantly correlated to the patients’ gender and the presence of lymph node metastases, but it was not significantly correlated to the type of pathology and regional or distant metastases. Ablation activities exceeding 5.55 GBq produce no further increase in the accumulated activity per volume of blood. The literature regarding this issue is scarce, and further studies are required to verify these preliminary results. Health Phys. 108(1):53–58; 201

« The electromagnetic interference of mobile phones on the function of a gamma camera »

Purpose: The aim of the present study is to evaluate whether or not the electromagnetic field generated by mobile phones interferes with the function of a single-photon emission computed tomography (SPECT) gamma camera during data acquisition. Methods and materials: We tested the effects of seven models of mobile phones on one SPECT gamma camera. The mobile phones were tested when making a call, in ringing mode, and in standby mode. The gamma camera function was assessed during data acquisition from a planar source and a point source of technetium-99m with activities of 10 mCi and 3 mCi, respectively. A significant decrease in count number was considered to be electromagnetic interference (EMI). Results: The percentage of induced EMI with the gamma camera per mobile phone was in the range of 0–100%. The incidence of EMI was mainly observed in the first seconds of ringing and then mitigated in the following frames. Conclusion: Mobile phones are portable sources of electromagnetic radiation, and there is interference potential with the function of SPECT gamma cameras leading to adverse effects on the quality of the acquired images. Keywords: Electromagnetic interference (EMI), mobile phones, gamma camera, single-photon emission computed tomography (SPECT

慢性硬膜下血腫例における99mTc-HM-PAOによる脳血流シンチグラフィ

金沢大学 核医原著論文/症例報

Technical and patient-related sources of error and artifacts in bone mineral densitometry using dual-energy X-ray absorptiometry: A pictorial review

Dual-energy X-ray absorptiometry is currently the standard and validated tool for measurement of bone mineral density and for the evaluation of osteoporosis. Current densitometry scanners based on dual-energy X-ray absorptiometry method produce two X-ray beams with different energies to differentiate the overlapped soft tissue and bony structures, by creating two different attenuation profiles. Procedural guidelines are available to technicians and physicians to guarantee the best practice, including consistent positioning during scanning and standard reporting. However, similar to other imaging modalities, dual-energy X-ray absorptiometry may be influenced by technical errors, and thus, imaging artifacts may arise and accuracy and precision of the results may be influenced. This issue may, in turn, affect the final result and interpretation. Hence, the article is arranged with the intention of presenting some less common and rare technical and patient-related sources of error and resultant artifacts, from poor patient preparation to acquisition and data processing. Where appropriate, the corresponding tables of densitometric results (bone mineral density) and statistical parameters (T- and Z-scores) are provided

Bone single photon emission computed tomography (SPECT) in a patient with Pancoast tumor: a case report

CONTEXT: Non-small cell lung carcinomas (NSCLCs) of the superior sulcus are considered to be the most challenging type of malignant thoracic disease. In this disease, neoplasms originating mostly from the extreme apex of the lung expand to the chest wall and thoracic inlet structures. Multiple imaging procedures have been applied to identify tumors and to stage and predict tumor resectability in surgical operations. Clinical examinations to localize pain complaints in shoulders and down the arms, and to screen for Horner's syndrome and abnormalities seen in paraclinical assessments, have been applied extensively for differential diagnosis of superior sulcus tumors. Although several types of imaging have been utilized for diagnosing and staging Pancoast tumors, there have been almost no reports on the efficiency of whole-body bone scans (WBBS) for detecting the level of abnormality in cases of superior sulcus tumors. CASE REPORT: We describe a case of Pancoast tumor in which technetium-99m methylene diphosphonate (Tc-99m MDP) bone single-photon emission-computed tomography (SPECT) was able to accurately detect multiple areas of abnormality in the vertebrae and ribs. In describing this case, we stress the clinical and diagnostic points, in the hope of stimulating a higher degree of suspicion and thereby facilitating appropriate diagnosis and treatment. From the results of this study, further clinical trials to evaluate the potential of SPECT as an efficient imaging tool for the work-up on cases of Pancoast tumor are recommended

Bone single photon emission computed tomography (SPECT) in a patient with Pancoast tumor: a case report

CONTEXT: Non-small cell lung carcinomas (NSCLCs) of the superior sulcus are considered to be the most challenging type of malignant thoracic disease. In this disease, neoplasms originating mostly from the extreme apex of the lung expand to the chest wall and thoracic inlet structures. Multiple imaging procedures have been applied to identify tumors and to stage and predict tumor resectability in surgical operations. Clinical examinations to localize pain complaints in shoulders and down the arms, and to screen for Horner's syndrome and abnormalities seen in paraclinical assessments, have been applied extensively for differential diagnosis of superior sulcus tumors. Although several types of imaging have been utilized for diagnosing and staging Pancoast tumors, there have been almost no reports on the efficiency of whole-body bone scans (WBBS) for detecting the level of abnormality in cases of superior sulcus tumors. CASE REPORT: We describe a case of Pancoast tumor in which technetium-99m methylene diphosphonate (Tc-99m MDP) bone single-photon emission-computed tomography (SPECT) was able to accurately detect multiple areas of abnormality in the vertebrae and ribs. In describing this case, we stress the clinical and diagnostic points, in the hope of stimulating a higher degree of suspicion and thereby facilitating appropriate diagnosis and treatment. From the results of this study, further clinical trials to evaluate the potential of SPECT as an efficient imaging tool for the work-up on cases of Pancoast tumor are recommended