Background Angiotensin converting enzyme 2 (ACE2), a target of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), demonstrates its highest surface expression in the lung, small bowel, an...

Background: Despite improvements in treatments, metastatic breast cancer remains difficult to cure. Bones constitute the most common site of first-time recurrence, occurring in 40–75% of cases. Therefore, evaluation for possible osseous metastases is crucial. Technetium 99 (⁹⁹Tc) bone scintigraphy and fluorodexossyglucose (FDG) positron emission tomography (PET)-computed tomography (PET-CT) are the most commonly used techniques to assess osseous metastasis. PET magnetic resonance (PET-MR) imaging is an innovative technique still under investigation. We compared the capability of PET-MR to that of same-day PET-CT to assess osseous metastases in patients with breast cancer. Methods: One hundred and nine patients with breast cancer, who underwent same-day contrast enhanced (CE)-PET-CT and CE-PET-MR, were evaluated. CE-PET-CT and CE-PET-MR studies were interpreted by consensus by a radiologist and a nuclear medicine physician. Correlations with prior imaging and follow-up studies were used as the reference standard. Binomial confidence intervals and a χ² test were used for categorical data, and paired t-test was used for the SUVmax data; a non-informative prior Bayesian approach was used to estimate and compare the specificities. Results: Osseous metastases affected 25 out 109 patients. Metastases were demonstrated by CE-PET-CT in 22 out of 25 patients (88%±7%), and by CE-PET-MR in 25 out of 25 patients (100%). CE-PET-CT revealed 90 osseous metastases and CE-PET-MR revealed 141 osseous metastases (P<0.001). The estimated sensitivity of CE-PET-CT and CE-PET-MR were 0.8519 and 0.9630, respectively. The estimated specificity for CE-FDG-PET-MR was 0.9884. The specificity of CE-PET-CT cannot be determined from patient-level data, because CE-PET-CT yielded a false-positive lesion in a patient who also had other, true metastases. Conclusions: CE-PET-MR detected a higher number of osseous metastases than did same-day CE-PET-CT, and was positive for 12% of the patients deemed osseous metastasis-negative on the basis of CE-PET-CT.

PET/MR enterography represents a new imaging tool for the noninvasive differentiation of fibrotic strictures from inflammatory strictures in Crohn disease. PurposeTo retrospectively evaluate positron emission tomography (PET)/magnetic resonance (MR) enterography for the differentiation of fibrotic strictures from inflammatory strictures in patients with Crohn disease.Materials and MethodsThis HIPAA–compliant retrospective study was approved by the institutional review board. Patients gave their written informed consent for study enrollment. PET/MR enterography images were evaluated in 19 patients with Crohn disease who had strictures that underwent surgical resection with pathologic confirmation. Two radiologists and a nuclear medicine physician in consensus evaluated the following bowel wall PET/MR enterography biomarkers: signal intensity (SI) on T2-weighted images, apparent diffusion coefficient (ADC), PET maximum standardized uptake value (SUVmax), SI on T2-weighted images × SUVmax, and ADC × SUVmax values at levels that corresponded to pathologic specimens. MR, PET, and hybrid PET/MR biomarkers were compared, and the performance for differentiation of i...

Institutional review board approval and informed consent were obtained. The purpose of the study was to prospectively perform magnetic resonance (MR) arthrography of the glenohumeral joint by using modified posterior approach without ultrasonographic or fluoroscopic guidance. A solution containing 0.1 mL of gadolinium chelate, 15 mL of saline, and 5 mL of 2% lidocaine was subsequently injected into the glenohumeral joint in 147 patients (81 men, 66 women; age range, 20-79 years). A 21-gauge needle was advanced along a trajectory connecting a skin mark 3-4 cm below and 2 cm medially to the posterolateral margin of the acromion and the coracoid process, as assessed with palpation, proceeding in posteroanterior direction. The joint was successfully entered at first attempt in 125 (85%) patients, at second attempt in 19 (13%), and at third attempt in three (2%). Contrast material-enhanced images were evaluated for presence, site, and maximal extent of contrast material extravasation; route of diffusion of the extravasation; compromised or noncompromised diagnostic quality; and presence of gas bubbles. Extravasation occurred in seven patients: at the interval between the teres minor muscle and infraspinatus muscle in five and within the infraspinatus muscle belly in two; extravasation had diffused along the teres minor muscle and infraspinatus muscle in five (71%) and along the teres minor muscle in two (29%). The mean extension of extravasation was 15 mm. Image quality was not compromised, and no gas bubbles were detected. The procedure was successful in all patients, with no complications.

The aim of the present study was to evaluate the performance of whole-body diffusion-weighted imaging (WB-DWI), whole-body positron emission tomography with computed tomography (WB-PET/CT), and whole-body positron emission tomography with magnetic resonance imaging (WB-PET/MRI) in staging patients with untreated invasive ductal carcinoma of the breast. Fifty-one women with newly diagnosed invasive ductal carcinoma of the breast underwent WB-DWI, WB-PET/CT and WB-PET/MRI before treatment. A radiologist and a nuclear medicine physician reviewed in consensus the images from the three modalities and searched for occurrence, number and location of metastases. Final staging, according to each technique, was compared. Pathology and imaging follow-up were used as the reference. WB-DWI, WB-PET/CT and WB-PET/MRI correctly and concordantly staged 33/51 patients: stage IIA in 7 patients, stage IIB in 8 patients, stage IIIC in 4 patients and stage IV in 14 patients. WB-DWI, WB-PET/CT and WB-PET/MRI incorrectly and concordantly staged 1/51 patient as stage IV instead of IIIA. Discordant staging was reported in 17/51 patients. WB-PET/MRI resulted in improved staging when compared to WB-PET/CT (50 correctly staged on WB-PET/MRI vs. 38 correctly staged on WB-PET/CT; McNemar's test; p<0.01). Comparing the performance of WB-PET/MRI and WB-DWI (43 correct) did not reveal a statistically significant difference (McNemar test, p=0.14). WB-PET/MRI is more accurate in the initial staging of breast cancer than WB-DWI and WB-PET/CT, however, the discrepancies between WB-PET/MRI and WB-DWI were not statistically significant. When available, WB-PET/MRI should be considered for staging patient with invasive ductal breast carcinoma.