Comparison of Thyroid Blood Flow and Uptake Indices Using Technetium-99m Pertechnetate in Patients with Graves’ Disease and Euthyroid Subjects

Objective: The aim of the present study was to evaluate parameters of early blood flow (EBF) including duration of EBF, perfusion index (PI), uptake indexes 1 and 2 (UI1 and UI2) derived from dynamic thyroid scintigraphy in patients with Graves’ disease (GD), and euthyroid (EI). Maximum instant uptake and maximum uptake of the thyroid gland were also assessed. Methods: A total of 50 patients with GD and EI were included in this study. Each patient underwent two dynamic scans of 1-minute (20 images at 3 seconds) and 20-minute (20 images at 1 minute) with 99mTcO4. The time-activity curve of a 1-minute scan was employed to derive EBF parameters; likewise, the time-activity curve of a 20-minute scan was used to determine maximum instant uptake, and the gradient of the curve from the 10th to 20th minute was used to assess maximum uptake. Results: Values of EBF duration, PI, UI1, UI2, and maximum instant uptake were significantly lower in patients with GD than in those with EI (p<0.05). The calculated gradient of the second half of the curves for all of the patients ranged from 0 to 0.88 and was significantly higher in patients with GD than in those with EI. Conclusion: Lower values of PI, UI1, UI2 and durations of EBF, along with faster maximum instant uptake in patients with GD in comparison to EI are indicators of a heightened desire for hyper-functioning thyroid glands of patients with GD to absorb 99mTcO4. Additionally, because of the uprising gradient at the end of the 20-minute time-activity curve, a maximum thyroid uptake of 99mTcO4 was achieved at more than 20 minutes after the radiopharmaceutical injection

Comparison of Thyroid Blood Flow and Uptake Indices Using Technetium-99m Pertechnetate in Patients with Graves’ Disease and Euthyroid Subjects

Objective: The aim of the present study was to evaluate parameters of early blood flow (EBF) including duration of EBF, perfusion index (PI), uptake indexes 1 and 2 (UI1 and UI2) derived from dynamic thyroid scintigraphy in patients with Graves’ disease (GD), and euthyroid (EI). Maximum instant uptake and maximum uptake of the thyroid gland were also assessed. Methods: A total of 50 patients with GD and EI were included in this study. Each patient underwent two dynamic scans of 1-minute (20 images at 3 seconds) and 20-minute (20 images at 1 minute) with 99mTcO4. The time-activity curve of a 1-minute scan was employed to derive EBF parameters; likewise, the time-activity curve of a 20-minute scan was used to determine maximum instant uptake, and the gradient of the curve from the 10th to 20th minute was used to assess maximum uptake. Results: Values of EBF duration, PI, UI1, UI2, and maximum instant uptake were significantly lower in patients with GD than in those with EI (p<0.05). The calculated gradient of the second half of the curves for all of the patients ranged from 0 to 0.88 and was significantly higher in patients with GD than in those with EI. Conclusion: Lower values of PI, UI1, UI2 and durations of EBF, along with faster maximum instant uptake in patients with GD in comparison to EI are indicators of a heightened desire for hyper-functioning thyroid glands of patients with GD to absorb 99mTcO4. Additionally, because of the uprising gradient at the end of the 20-minute time-activity curve, a maximum thyroid uptake of 99mTcO4 was achieved at more than 20 minutes after the radiopharmaceutical injectio

Comparison of 180° and 360° Arc Data Acquisition to Measure Scintigraphic Parameters from Gated Single Photon Emission Computed Tomography Myocardial Perfusion Imaging: Is There Any Difference?

Objective: The aim of the current study was to compare 180° and 360° data collection modes to measure end diastolic volume (EDV), end systolic volume (ESV) and ejection fraction (EF) values of the cardiac system by gated myocardial perfusion tomography. Methods: Thirty-three patients underwent gated myocardial perfusion tomography. Single photon emission computed tomography data of patients’ heart were acquired by 180°, 45° left posterior oblique to 45° right anterior oblique, and 360° to obtain EDV, ESV, EF and cardiac volume changes (V1, V2, V3, V4, V5, V6, V7 and V8) throughout each cardiac cycle. Results: Results of the current study indicated that there were no significant differences between 180° and 360° angular sampling in terms of measuring EDV, ESV and EF in myocardial perfusion imaging. Cardiac volume change patterns during a cardiac cycle were also similar in 360° and 180° scans. We also observed that there was no difference in EDV, ESV and EF values between the group with stress induced by exercise and the group with stress imposed by dipyridamole. Conclusion: As there is no difference between 180°and 360° cardiac scanning in terms of EDV, ESV and EF, half-orbit scan is recommended to study these cardiac system parameters because it offers more comfort to patients and a shorter scanning time. Keywords: 180° data collection, 360° data collection, ejection fraction, end diastolic volume, end systolic volume, gated myocardial perfusio

False-positive defects on exercise 99mTc-sestamibi SPECT imaging, but not on dipyridamole 99mTc-sestamibi SPECT imaging, in a patient with right bundle branch block (RBBB)

False-positive findings with myocardial perfusion imaging (MPI)have frequently been identified in the presence of left bundlebranch block (LBBB) and tend to lower the accuracy of MPI inindividuals with normal coronary angiographs. Pharmacologicstress is recognized as the preferred method for MPI in patientswith LBBB. In contrast, very few studies have evaluated the effectof right bundle branch block (RBBB) on MPI, and there isno consensus regarding the selection of pharmacologic versusexercise stress during MPI for the RBBB patient. In this study,we present a 45-year-old man with RBBB, who has a normal coronary artery angiography, but who showed abnormal myocardialperfusion with exercise MPI, and normal perfusion ondipyridamole MPI. The aim of the study is to stimulate awarenessthat the stress method selected for patients with RBBB canpotentially interfere with the accuracy of the data

Relation between clinical features and gastric emptying time in diabetic patients

BACKGROUND: Gastroparesis is characterized by delayed gastric emptying. This pathology is usually observed in patients with diabetes. One standard approach to quantitative assessment of gastric emptying is scintigraphic study. The aim of present study was to perform scintigraphic study of gastric emptying time in patient with diabetes and to find its correlation with patients’ characteristics. MATERIALS AND METHODS: Gastric emptying was assessed in 19 patients with type 2 diabetes (mean age of 61.04 ± 6.09 years) and 6 healthy volunteers. Characteristics of the patients were sex, age, duration of diabetes, blood sugar and serum HbA1c level. RESULTS: Results of present study revealed that gastric emptying half time was significantly larger in patients with type 2 diabetes as compared with healthy volunteers (P-value &lt; 0.05). While correlation of sex, age, duration of diabetes and blood sugar with gastric emptying time was not statistically significant, HbA1c level had significant effect on gastric emptying time. CONCLUSION: Results of this prospective study indicated that level of serum HbA1c is an effecting factor on gastric emptying time in patients with type 2 diabetes; however, these preliminary findings should be validated in larger and well-designed studies

The association of increased stomach wall radiotracer uptake with prolonged use of Omeprazole capsules on myocardial perfusion imaging (MPI) using 99mTc-sestamibi SPECT

Myocardial perfusion imaging (MPI) is widely used in routinepractice for diagnosis and risk stratification of coronary arterydisease (CAD). Intense curvilinear activity in the stomach wallof a patient was seen on MPI raw data. This phenomenon was completely dissimilar to the familiar intraluminal gastricreflux of sestamibi. This observed activity could have resultedin false-positive or false-negative artifacts — and inaccurate diagnosis — of the inferior wall of the left ventricle after MPI processing. On further exploration, the current researchers found that the patient had a history of 10-year Omeprazole capsule consumption. The authors present this infrequent case of intense stomach uptake to stress the related clinical and diagnostic implications with the aim to stimulate acute awareness of possible, unexpected infringements on image quality that could potentially interfere with accurate interpretation of the data

Relation between clinical features and gastric emptying time in diabetic patients

BACKGROUND: Gastroparesis is characterized by delayed gastric emptying. This pathology is usually observed in patients with diabetes. One standard approach to quantitative assessment of gastric emptying is scintigraphic study. The aim of pre- sent study was to perform scintigraphic study of gastric emptying time in patient with diabetes and to find its correlation with patients’ characteristics. MATERIALS AND METHODS: Gastric emptying was assessed in 19 patients with type 2 diabetes (mean age of 61.04 ± 6.09 years) and 6 healthy volunteers. Characteristics of the patients were sex, age, duration of diabetes, blood sugar and serum HbA1c level. RESULTS: Results of present study revealed that gastric emptying half time was significantly larger in patients with type 2 diabetes as compared with healthy volunteers (P-value < 0.05). While correlation of sex, age, duration of diabetes and blood sugar with gastric emptying time was not statistically significant, HbA1c level had significant effect on gastric emptying time. CONCLUSION: Results of this prospective study indicated that level of serum HbA1c is an effecting factor on gastric emptying time in patients with type 2 diabetes; however, these preliminary findings should be validated in larger and well-designed studies

False-positive defects on exercise 99mTc-sestamibi SPECT imaging, but not on dipyridamole 99mTc-sestamibi SPECT imaging, in a patient with right bundle branch block (RBBB)

False-positive findings with myocardial perfusion imaging (MPI) have frequently been identified in the presence of left bundle branch block (LBBB) and tend to lower the accuracy of MPI in individuals with normal coronary angiographs. Pharmacologic stress is recognized as the preferred method for MPI in patients with LBBB. In contrast, very few studies have evaluated the effect of right bundle branch block (RBBB) on MPI, and there is no consensus regarding the selection of pharmacologic versus exercise stress during MPI for the RBBB patient. In this study, we present a 45-year-old man with RBBB, who has a normal It has been reported that conduction abnormality may be related to ischemic heart disease (IHD) and therefore detection of coronary artery disease (CAD) in these patients is essential [1]. Since in left bundle branch block (LBBB) patients the exercise stress test is inconclusive, the use of a non-invasive modality, such as myocardial perfusion imaging (MPI), is applied for screening purposes [2]. However, false-positive findings with myocardial perfusion imaging (MPI) have been frequently noted in the presence of left bundle branch block (LBBB) and tend to lower the accuracy of MPI in individuals with normal coronary angiographs [3]. Pharmacologic stress is therefore recognized as the preferred method for MPI in patients with LBBB [4]. In contrast, very few studies have evaluated the effect of right bundle branch block (RBBB) on MPI, and there is no consensus concerning the selection of a pharmacologic versus an exercise stress method during MPI for the RBBB patient [5]. We present a 45-year-old man with RBBB and with a normal coronary artery angiograph, who showed abnormal myocardial perfusion with exercise MPI, and normal perfusion on dipyridamole MPI, with the aim of stimulating awareness that the stress method selected for these patients can potentially interfere with the accuracy of the data

The association of increased stomach wall radiotracer uptake with prolonged use of Omeprazole capsules on myocardial perfusion imaging (MPI) using 99mTc-sestamibi SPECT

Myocardial perfusion imaging (MPI) is widely used in routine practice for diagnosis and risk stratification of coronary artery disease (CAD). Intense curvilinear activity in the stomach wall of a patient was seen on MPI raw data. This phenomenon was completely dissimilar to the familiar intraluminal gastric reflux of sestamibi. This observed activity could have resulted in false-positive or false-negative artifacts — and inaccurate diagnosis — of the inferior wall of the left ventricle after MPI processing. On further exploration, the current researchers found Myocardial perfusion imaging (MPI) with exercise or pharmacological stress, either with thallium-201 (201Tl) or technetium-99m (99mTc)-sestamibi, is widely used for preparation of diagnostic and prognostic information regarding patients with proved or possible coronary artery disease (CAD) and it facilitates the accurate management of CAD patients [1]. However, with present myocardial radiotracers, such as 99mTc-sestamibi, rather high extra-cardiac activity is usually seen, which is mostly associated with physiologic hepatobiliary or renal excretion [2]. In contrast, there are limited reports suggesting possible non-physiologic reasons for these visceral uptakes, and occasionally, indicating different underlying pathologies [2]. Indeed, accidental pathological fi ndings during myocardial perfusion imaging are not scarce and cautious examination of the full fi eld of image acquisition has been useful in identifying these accidental fi ndings [3–5]. Alternatively, most efforts concentrate on dissolving these interfering abdominal activities without attention to the clinical importance of such fi ndings [6, 7]. On the MPI raw data of one such patient, intense curvilinear activity in the stomach wall was evident. This phenomenon was completely dissimilar to the familiar intraluminal gastri