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Background: Real-time sequences allow functional evaluation of various joint structures during a continuous motion and help understand the pathomechanics of underlying musculoskeletal diseases., Purpose: To assess and compare the image quality of the two most frequently used real-time sequences for joint dynamic magnetic resonance imaging (MRI), acquired during finger and ankle joint motion., Material and Methods: A real-time dynamic acquisition protocol, including radiofrequency (RF)-spoiled and balanced steady-state free precession (bSSFP) sequences, optimized for temporal resolution with similar spatial resolution, was performed using a 3.0-T MRI scanner on 10 fingers and 12 ankles from healthy individuals during active motion. Image quality criteria were evaluated on each time frame and compared between these two sequences. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were determined and compared from regions of interest placed on cortical bone, tendon, fat, and muscle. Visualization of anatomical structures and overall image quality appreciation were rated by two radiologists using a 0-10 grading scale., Results: Mean CNR was significantly higher with bSSFP sequence compared to RF-spoiled sequence. The grading score was in the range of 5-9.3 and was significantly higher with RF-spoiled sequence for bone and joint evaluation and overall image appreciation on the two joints. The standard deviation for SNR, CNR, and grading score during motion was smaller with RF-spoiled sequence for both the joints. The inter-reader reliability was excellent (>0.75) for evaluating anatomical structures in both sequences., Conclusion: A RF-spoiled real-time sequence is recommended for the in vivo clinical evaluation of distal joints on a 3.0-T MRI scanner.

Objective: To evaluate the value of psoas muscle proximal insertion for correct numbering of the lumbar vertebrae in MRI, in particular in case of lumbosacral transitional vertebra (LSTV)., Methods: Two radiologists assessed 477 MRI scans of the lumbar spine with a sagittal localizer sequence on the whole spine for numbering vertebrae caudally from C2. Proximal insertion of the psoas was determined as the most proximal vertebra with psoas over half of its body on coronal T2 STIR sequence. The last lumbar vertebra was named considering both its number and the presence or absence of LSTV according to Castellvi classification. These same parameters were also assessed on 207 PET-CT scans of another cohort including the whole spine., Results: Proximal insertion of the psoas was L1 in 94.1% of cases: 98.5% in case of modal anatomy, 81.4% in case of LSTV, and 51.7% in case of missing or supernumerary lumbar vertebra without LSTV. There was no statistically significant difference between MRI and CT data. The inter-reader agreement for determination of psoas proximal insertion was excellent (kappa = 0.96)., Conclusion: Proximal insertion of the psoas muscle is a helpful marker for correct numbering of the lumbar vertebrae in MRI and to detect a complete lumbosacral segmentation anomaly., Key Points: • Proximal insertion of the psoas muscle can be easily identified on a coronal T2 STIR sequence. • Psoas proximal insertion on the spine almost always designates the first lumbar vertebra and is helpful to accurately number all lumbar vertebrae, especially in case of lumbosacral transitional vertebra. • Conversely, when psoas muscle does not insert five lumbar bodies above the apparent lumbosacral joint, the probability of variation in the number of lumbar vertebrae is high.

Objectives/hypothesis: The aim of this study was to assess and compare the diagnostic accuracy of 18 fluorodesoxyglucose positron emission/computed tomography (FDG-PET/CT) and magnetic resonance imaging (MRI) to detect T1-T2 head and neck squamous cell carcinoma (HNSCC)., Study Design: Prospective case series., Methods: Thirty-five consecutive patients with histologically proven T1-T2 HNSCC were prospectively included. All patients underwent pretherapeutic FDG-PET/CT and MRI. Two nuclear medicine physicians and 2 radiologists blindly reviewed all FDG-PET/CT and MRI, respectively. A five-point qualitative scale was used to estimate tumor detection ability. Sensitivity of each modality was compared together using a McNemar test. Interobserver variability was assessed by kappa index (κ) of Cohen statistics. Maximal standardized uptake value (SUV MAX ), metabolic tumor volume (MTV) in FDG-PET/CT, and gadolinium enhancement (%GE) in MRI of each tumor were recorded and compared with T stage using a Mann-Whitney test. Tumor-to-normal tissue ratios in FDG-PET/CT and MRI (TNR PET and TNR MRI ) were calculated and compared together using a Student t test., Results: Among the 35 primary tumors, 29 were detected by FDG-PET/CT and 22 by MRI. MRI detected none of the six lesions incorrectly identified by FDG-PET/CT. FDG-PET/CT correctly identified seven of the 13 MRI false-negative results. Sensitivity of FDG-PET/CT to detect T1-T2 HNSCC was significantly higher than MRI (83% vs. 63%, P = .015). T stage was significantly correlated with MTV (P = .002) unlike with SUV MAX (P = .06) and %GE (P = .70). TNR PET was significantly higher than TNR MRI (3.5 ± 3.2 vs. 1.2 ± 0.3, P < .0001)., Conclusions: Our study showed a higher diagnostic accuracy of FDG-PET/CT than MRI to detect T1-T2 HNSCC with a good interobserver agreement., Level of Evidence: 4. Laryngoscope, 128:378-385, 2018., (© 2017 The American Laryngological, Rhinological and Otological Society, Inc.)

Objectives: There are significant numbers of military and law enforcement bullets containing ferromagnetic materials. This study aimed to assess the magnetic field interactions for a representative sample of military and law enforcement ballistic objects at 1.5 and 3 tesla (T) to create a magnetic resonance imaging (MRI) compatibility database., Methods: Twenty-nine different bullets underwent MRI evaluation. The deflection angle method and a qualitative torque scale were used. The samples were representative of those commonly used in the North Atlantic Treaty Organization (NATO) military forces (e.g., 5.56 mm NATO), law enforcement agencies (e.g., 9 mm Parabellum), and encountered in war injuries and crime-related trauma (e.g., 7.62 mm Kalashnikov)., Results: At all static magnetic field strengths, all non-nickel- and nonsteel-containing bullets exhibited no movement (deflection angle = 0°; torque = 0), whereas eight bullets containing steel core, steel jacket, or nickel jacket exhibited substantial magnetic field interactions over and above what might be regarded as safe in vivo (deflection angle = 90°; torque = 4+)., Conclusion: Military and law enforcement non-nickel- or nonsteel-containing bullets appear to be safe for patients in MRI system at 1.5 and 3 T. On the other hand, nickel- and steel-containing bullets exhibit movements that are considered potentially unsafe for patients in an MRI environment., (Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.)

Objectives: To study the role and indications of breast MRI in normal breast screening., Patients and Methods: Retrospective study of 51 patients (mean age of 51 years) conducted in northern Finistère. Each patient had a normal (BI-RADS 1 or 2) breast screening (mammography and echography). Four indications for MRI were chosen: screening of high-risk patients, high-density breasts, radio-clinical discordance, and breasts prostheses. Breast MRI were reviewed according to BI-RADS classification. Abnormalities categorized in BI-RADS 4 or 5 were confirmed histologically., Results: Thirteen patients underwent histological analysis. Nine invasive carcinomas were identified (six invasive lobular carcinomas (ILC), two mixed carcinomas, one invasive ductal carcinoma). For these patients, the reason for performing MRI was a radio-clinical discordance., Discussion and Conclusion: The study demonstrates the breast MRI value for radio-clinical discordance and the key role of MRI in diagnostic challenge of ILC. In literature review, MRI has a role even if breast screening is normal: radio-clinical discordance, screening of patients with high-risk, breasts prostheses in certain cases. Breast density comes as an additional criteria to perform this exam.

Objectives: To study the role and indications of breast MRI in normal breast screening. Patients and methods: Retrospective study of 51 patients (mean age of 51 years) conducted in northern Finistère. Each patient had a normal (BI-RADS 1 or 2) breast screening (mammography and echography). Four indications for MRI were chosen: screening of high-risk patients, high-density breasts, radio-clinical discordance, and breasts prostheses. Breast MRI were reviewed according to BI-RADS classification. Abnormalities categorized in BI-RADS 4 or 5 were confirmed histologically. Results: Thirteen patients underwent histological analysis. Nine invasive carcinomas were identified (six invasive lobular carcinomas (ILC), two mixed carcinomas, one invasive ductal carcinoma). For these patients, the reason for performing MRI was a radio-clinical discordance. Discussion and conclusion: The study demonstrates the breast MRI value for radio-clinical discordance and the key role of MRI in diagnostic challenge of ILC. In literature review, MRI has a role even if breast screening is normal: radio-clinical discordance, screening of patients with high-risk, breasts prostheses in certain cases. Breast density comes as an additional criteria to perform this exam. [Copyright &y& Elsevier]