American journal of nuclear medicine and molecular imaging最新文献

Primary pulmonary artery sarcoma (PAS) is a malignant neoplasm of the pulmonary vascular system originating from the intima, with clinical and imaging manifestations similar to those of pulmonary thromboembolism (PTE), and is often misdiagnosed. Spectral CT and PET/CT can clearly show the extent and metastasis of PAS and are valuable in visualizing adjacent structures such as lungs, bronchi, and mediastinum, providing a strong imaging basis for the diagnosis and differentiation of PAS, allowing treatment monitoring and follow-up.

When injected intravenously, [^99mTc]Tc-phytate forms particles in the nanometer range. This size can favor its extravasation into tumor and inflammation through pores of the vasculature. The aim of this work is the evaluation of the use of [^99mTc]Tc-phytate to assess sterile inflammation in mouse models. Biodistribution studies of [^99mTc]Tc-phytate were performed in two groups of male Swiss Albino mice. Sterile inflammation was induced after intramuscular injection of turpentine in the first group (chemically induced sterile inflammation model) and after implantation of sterile metal bolts in the second group (foreign-body induced sterile inflammation model). [^99mTc]Tc-phytate was intravenously injected after the development of inflammation in both groups and ex vivo biodistribution of the radiolabelled complex followed at different time-points. Biodistribution was expressed as percent injected dose per gram (%ID/g). Target-to-background ratios were also recorded. For the chemically induced sterile inflammation model, ex vivo biodistribution evaluation measurements revealed a pronounced uptake in the inflamed muscle when compared to uptake in the control/non-inflamed muscle. Moreover, as expected, there is a high uptake in the liver and spleen. For the foreign-body induced sterile inflammation model, a significantly higher uptake was observed in the inflamed muscle post [^99mTc]Tc-phytate injection, both for the 24 hours post-bolt implantation and for the 7 days post-bolt implantation groups. The nanoparticle properties of [^99mTc]Tc-phytate are potentially useful in the imaging of different types of sterile inflammation with translational potential clinical SPECT (single photon emission computed tomography) imaging applications in humans.

Intracerebral hemorrhage is one of the types of stroke in patients with risk factors. In this study, we aimed to evaluate the initial computed tomography (CT) scan findings, clinical manifestations and possible risk factors of patients with intracerebral hemorrhage. This is a cross-sectional study that was performed in 2015-2022 on 900 patients with definite diagnosis of intracerebral hemorrhage. Data of patients were evaluated for patient's age, gender, clinical manifestations, primary radiologic signs in CT scan and possible risks factors for stroke. Lobar hemorrhage was the most common site of involvement (324 patients, 36%) followed by lenticular (putamen) (294 patients, 32.7%) and thalamus (135 patients, 15%). Among patients, 543 patients (60.3%) had hypertension, 81 patients (9%) had histories of anticoagulant. Hemorrhages in putamen were significantly more common in patients with hypertension (P<0.001) and lobar hemorrhages were significantly more common in patients with the use of anticoagulant drugs (P=0.033). The most common presentation of hemorrhagic stroke was decreased consciousness level (428 patients, 47.5%) followed by headache (343 patients, 38.1%), coma (81 patients, 9%) and seizure (48 patients, 5.4%). Evaluation of the relationships between patient's main symptoms and sites of involvement showed that patients with decreased consciousness as their most common symptom had more frequently diagnosed with lobar hemorrhage (54%) and putamen hemorrhage (30.4%) (P<0.001). Hypertension was the most common past medical history that was significantly related to hemorrhage in basal nuclei. Hemorrhages in putamen were common in hypertensive patients and lobar hemorrhages were common in patients with anticoagulant use.

While the presence of incidental breast and lung masses on cardiac scans is well known, renal masses are often incidentally discovered as well on cardiac examinations, some of which are malignant. We searched the electronic medical record system over the past 18 years, since the system was installed, for patients with a cardiac rubidium-82 (⁸²Rb) rubidium PET/CT or technetium-99m (^99mTc) sestamibi SPECT/CT performed within 1 year of a renal-protocol CT or MR. Each PET/CT or SPECT/CT was examined for presence of a renal lesion on the attenuation-correction CT images. We found 43 SPECT/CT and 18 PET/CT studies which fit the desired criteria. Of these, 7 SPECT/CT studies and 2 PET/CT studies demonstrated the renal mass on at least one of the two sets of CT images (rest or stress); if not visible, most commonly the tumor was either out of the field of view or had already been removed. Of these, 6 SPECT/CT and 2 PET/CT studies demonstrated a malignancy. Cardiac SPECT/CT and PET/CT images demonstrate incidental renal masses with a non-negligible frequency, and CT images should be carefully examined.

We performed this study to evaluate the correlation between Body Mass Index (BMI) and Exposure Rate (ER) of hyperthyroid patients treated with iodine-131 so that in case of any relationship, we can improve the prescribed dose for the treatment of hyperthyroid patients and its side effects on the body and the environment. In this analytical and cross-sectional study, 30 patients with hyperthyroidism treated with liquid iodine-131 were randomly selected. We recorded demographic indicators (age, height, and weight) and ER. Patients were treated with the activity of 8-29 mCi (mean 14.4 mCi) oral I-131. The external radiation of patients was measured from a distance of one meter parallel to the patient's thyroid gland at intervals of 6 to 24 hours post-iodine-131 administration. ER measurements and other acquired data were statistically analyzed by R software and its methods. Data were normalized using the Shapiro method, and due to the non-normality of the data in the correlation test, the Spearman method was used. The measurements of this study represent two main findings: 1. There is a significant relationship between ER and iodine-131 activity because the observed significance level (P-value =0.002) is smaller than the predicted error value (0.01). 2. There is no significant relationship between ER and BMI because the observed significance level (P-value =0.082) is greater than the predicted error value (0.05). The present study's findings show a negative relationship between BMI and ER. Still, since the P-value is more than 0.05, this relationship is not statistically significant.

Background: Considering the importance of vascular age in the risk assessment of cardiovascular events and the presence of different methods for its estimation, this study aims to evaluate and compare vascular age according to coronary artery calcium scoring (CACS) and carotid ultrasonography.

Methods: This study was conducted in Isfahan on patients who underwent CACS and carotid intima-media thickness (CIMT) assessments within 30 days. In patients who were candidates for CACS, calcium score was measured, then they were invited for carotid ultrasonography, and CIMT was measured. Vascular age was estimated based on these methods using available formulas.

Results: In this study, 115 patients were enrolled. (Male 52.2%, female 47.8%). The mean chronological age was 59.08 ± 14.90 years old. The mean calcium score (CS) of patients was 48.23 ± 63.34. Mean CIMT was 0.73 ± 0.15 mm. The mean vascular age derived by CS and CIMT was 58.64 ± 12.63 and 53.99 ± 17.53 years, respectively. The vascular age obtained by CS was directly related to vascular age based on CIMT (P-value < 0.05).

Conclusion: Calcium score is as helpful as CIMT for vascular age estimation.

Purpose: To directly compare the performance of pelvic mpMRI versus recently approved and increasingly used PSMA-based ¹⁸F-DCFPyL PET/CT in intermediate-high risk and biochemical recurrent prostate cancer patient cohort while exploring their potential differing applications in specific clinical scenarios.

Methods: A retrospective analysis was performed on patients who had ¹⁸F-DCFPyL PET/CT and pelvic mpMRI done from September 2021 to January 2022 at a single institution. The inclusion criteria were paired exams within a 3-month interval. Exclusion criteria were intervening treatment between exams, a change in PSA by more than 50% and absolute difference more than 1 ng/mL, or concurrent history of other malignancy. Abnormal lesions on these 2 imaging exams were reviewed with the identification of concordant and discordant imaging findings. The findings were verified by pathology or other imaging techniques within minimal 5-month clinical follow-up.

Results: A total of 57 patients with 57 paired exams were included. The rate of concordant exams was 43/57 or 75.4%. Lesion-based analyses of sensitivity, specificity, PPV and NPV for mpMRI and ¹⁸F-DCFPyL PET/CT in the prostate bed were 96%, 94%, 98%, 89% and 96%, 100%, 100%, 90% respectively. For pelvic lymph node metastases, the sensitivity, specificity, PPV and NPV for mpMRI and ¹⁸F-DCFPyL PET/CT were 52%, 100%, 100%, 55% and 100%, 100%, 100%, 100% respectively. For bone metastases, the sensitivity, specificity, PPV and NPV for mpMRI and ¹⁸F-DCFPyL PET/CT were 86%, 73%, 50%, 94% and 100%, 98%, 95%, 100% respectively. Exact McNemar's test for paired data suggested that in diagnostic performance between ¹⁸F-DCFPyL PET/CT and mpMRI was not statistically significant in prostate bed (p-value = 1.00), but significantly in pelvic lymph nodes (p-value < 0.0001) and bone lesions (p-value = 0.0026).

Conclusion: Our study demonstrated that PSMA-based ¹⁸F-DCFPyL PET/CT and pelvic mpMRI have a good concordance rate in the detection of primary or recurrence prostate disease and can have complementary roles in the clinical assessment of the prostate bed lesions. However, there are key differences in their performance, with the notably superior performance of PSMA-based ¹⁸F-DCFPyL PET/CT in the detection of small metastatic nodal disease and bone metastases.

We present a case of abnormal findings on a Tc99m-Sestamibi parathyroid scan, post COVID-19 vaccination. The patient is a 48-year-old female presenting for evaluation of hyperparathyroidism who received the mRNA-1273 Moderna (ModernaTX, Inc.) vaccine seven days prior to the scan. The patient is right hand dominant and reported no traumatic events, inflammation, infection, or extraneous use of the left arm. The patient did report "soreness" of the extremity starting approximately 24 hours post injection which continued to the time of the study.

Malignant melanoma (MM) is an aggressive malignant tumor, which mostly occurs on the skin, uvea, etc. The mucosal MM accounts for a small proportion of all MM and can occur in the digestive tract. Primary MM of the digestive tract is rare and can be found in the middle and lower third of the esophagus and the rectum containing melanocytes. Primary rectal MM often occurs in middle-aged and elderly women, with rapid progress and strong invasion. We report a case of a 61-year-old man diagnosed with primary malignant melanoma of the rectum with liver metastases mimicking rectum cancer. ¹⁸F-FDG PET/CT showed the rectal wall was markedly thickened with a high metabolic level (SUVmax 10.6) and the boundary between the lesions and the prostate was unclear. In addition, increased FDG uptake were found in multiple lymph nodes, lung, liver, and bones, suggesting metastasis. In this case, ¹⁸F-FDG PET/CT shows the advantage of evaluating the whole-body situation and provides valuable information for the diagnosis, tumor stage, evaluation of treatment efficacy, and prognosis of MM.

While reduced global brain metabolism is known in aging, Alzheimer's disease (AD), small vessel disease (SVD) and delirium, explanation of regional brain metabolic (rBM) changes is a challenge. We hypothesized that this may be explained by "triage phenomenon", to preserve metabolic supply to vital brain areas. We studied changes in rBM in 69 patients with at least 5% decline in global brain metabolism during active lymphoma. There was significant decline in the rBM of the inferior parietal, precuneus, superior parietal, lateral occipital, primary visual cortices (P<0.001) and in the right lateral prefrontal cortex (P=0.01). Some areas showed no change; multiple areas had significantly increased rBM (e.g. medial prefrontal, anterior cingulate, pons, cerebellum and mesial temporal cortices; P<0.001). We conclude the existence of a physiological triage phenomenon and argue a new hypothetical model to explain the shared events in the pathophysiology of aging, AD, SVD and delirium.