UNASSIGNED: Previous research in sport populations has demonstrated that abnormal magnetic resonance imaging (MRI) findings may be present in individuals without symptoms or known pathology. Extending this understanding to ballet, particularly in relation to the foot and ankle, is important to guide medical advice given to dancers.
UNASSIGNED: To assess foot and ankle MRI scans in asymptomatic ballet dancers focusing on bone marrow edema and the posterior ankle and to investigate whether these MRI findings would become symptomatic within 1 year.
UNASSIGNED: Case series; Level of evidence, 4.
UNASSIGNED: In total, 31 healthy dancers (62 feet/ankles; 15 male and 16 female; age, 26.5 ± 4.3 years) who were dancing in full capacity were recruited from an elite professional ballet company. Orthogonal 3-plane short tau inversion recovery imaging of both feet and ankles was obtained using 3T MRI and the images were reviewed using a standardized evaluation form by 2 musculoskeletal radiologists. Injuries in the company were recorded and positive MRI findings were assessed for correlation with any injuries requiring medical attention during the subsequent 12 months.
UNASSIGNED: A total of 51 (82%) of the 62 feet and ankles had ≥1 area of bone marrow edema. The most common locations of bone marrow edema were the talus (n = 41; 66%), followed by first metatarsal (n = 14; 23%). Os trigonum and Stieda process were seen in 5 (8%) and 8 (13%) ankles, respectively. Among them, 2 os trigona showed bone marrow edema. Fluid in the anterior and posterior talocrural joints and the subtalar joint was observed in 48%, 63%, and 63% of these joints, respectively. Fluid around foot and ankle tendons was observed, with the most prevalent being the flexor hallucis longus tendon (n = 13; 21%). Two dancers who had positive findings on their MRI subsequently developed symptoms during the next 12 months.
UNASSIGNED: Positive MRI findings are commonplace in the foot and ankle of asymptomatic professional ballet dancers. The majority do not result in the development of symptoms requiring medical attention within 12 months. Careful interpretation of MRI findings with the dancer\'s clinical picture is required before recommending activity modification or further intervention.

暂无摘要。

Magnetic resonance imaging (MRI) was applied to determine the sex of polar cod (Boreogadus saida Lepechin, 1774) (Actinopterygii: Gadidae) and to follow the gonadal development in individual animals over time. Individual unanaesthetised fish were transferred to a measurement chamber inside a preclinical 9.4 T MRI scanner and continuously perfused with aerated seawater. A screening procedure at an average of 3.5 h, consisting of a set of MRI scans of different orientations, was repeated every 4 weeks on the same set of reproducing B. saida (n = 10) with a body length of about 20 cm. Adapted multi-slice flow-compensated fast low-angle shot (FcFLASH) and rapid acquisition with relaxation enhancement (RARE) protocols with an in-plane resolution of 313 μm and an acquisition time of 2.5 min were used to visualise the morphology of various organs, including the gonads within the field of view (FOV). The MR images provided high resolution, enabling specific sex determination, calculation of gonad volumes, and determination of oocyte sizes. Gonad maturation was followed over 4 months from November 2021 until shortly before spawning in February 2022. The gonad volume increased by 2.3-25.5% for males and by 11.5-760.7% for females during the observation period. From October to February, the oocyte diameter increased from 427 μm (n = 1) to 1346 ± 27 μm (n = 4). Interestingly, individual oocytes showed changes in MR contrast over time that can be attributed to the morphological development of the oocytes. The results fit well with previous literature data from classical invasive studies. The presented approach has great potential for various ecophysiological applications such as monitoring natural or delayed development of internal organs or sex determination under different environmental conditions.

OBJECTIVE: To evaluate the feasibility of use of an 1.5 T magnetic resonance (MR)-linear accelerator MR-linac for imaging in gynaecologic high-dose-rate (HDR) brachytherapy. Method: Commissioning measurements for MR images quality control, geometric distortion, dwell position accuracy, applicator reconstruction and end-to-end test for a tandem-and-ring applicator were performed following the recommendations of American Brachytherapy Society, International Commission on Radiation Units and Measurements and Report of the Brachytherapy Working Group of the Spanish Society of Medical Physics. The values for MR-based IGABT were compared to the corresponding values with computed tomography (CT). Results: Measured distorsions for the MR images were less than 0.50 mm compared to the CT images. The differences between 3D displacements for all dwell positions were 0.66 mm and 0.62 mm for the tandem and ring, respectively. The maximum difference is 0.64 mm for the distances from the applicator tip obtained using the films. The CT and MR dose differences for the right and left \'A\' points were 0.9% and -0.7%, respectively. Similar results were observed in terms of dose distribution for CT and MR. The gamma passing rate was 99.3% and 99.5%, respectively. Conclusion: The use of MR images from an MR-linac used in a radiotherapy service for gynaecological brachytherapy was proved to be feasible, safe and precise as the geometrical differences were less than 1 mm, and the dosimetric differences were less than 1% when comparing to the use of CT images for the same purpose.

Intraventricular neurocytoma is a low incidence central nervous system tumor. It predominantly affects young adults with no apparent gender predilection. The main symptoms include headache, nausea and vomiting. These result from hydrocephalus due to the obstruction of cerebrospinal fluid flow. On diagnostic imaging, neurocytoma can be suspected by some features, such as peripheral cysts, lobulated contours and septa that bridge the ventricular wall, giving a \"scalloped\" appearance. There are other characteristics, but they are less specific for the diagnosis. The atypical variant of neurocytoma is even rarer and leads to a worst prognosis. Atypical neurocytomas develop higher proliferative potential identified by the Ki-67 biomarker and higher recurrence rate. There are few studies about the imaging characteristics of atypical neurocytomas. At this point, there are no reliable distinctive features to differentiate atypical neurocytomas, especially due to their low incidence. We present the case of a 20-year-old female patient with symptoms of intracraneal hypertension. CT and MRI of the brain revealed a mass occupying the body of the left lateral ventricle, adjacent to the foramen of Monro. The mass was primarily solid with discrete peripheral cyst and a few scalloped areas. It also showed signs of supratentorial obstructive hydrocephalus. The tumor was partially removed because of bleeding and compromise of vascular structures. Immunohistochemistry revealed positive synaptophysin, elevated Ki-67 (7%), increased number of blood vessels and moderate nuclear atypia. After surgery, the patient persisted with signs of intracranial hypertension, not improving with clinical management and requiring aggressive surgical procedures. While rare, atypical neurocytoma requires a better characterization, especially through imaging, to optimize immediate management and explore new therapeutic options.

OBJECTIVE: This study aimed to assess the practical application of conventional two-dimensional (2D) pelvic ultrasound in conjunction with three-dimensional (3D) ultrasound for evaluating obstructive Müllerian abnormalities.
METHODS: Respective study in tertiary referral hospital METHOD: Computerized stored data was used to collect surgical confirmed obstructive Müllerian anomalies cases between December 2022 and October 2023 with presurgical imagings being evaluated. Acute presentation with abdominal pain and clinical suspicion of obstructive Müllerian abnormality were required for inclusion. All study participants underwent pelvic ultrasound prior to the definitive surgery, with or without a repeat MRI if one was performed previous to admission. Those situations where both MRI and ultrasound were not conducted were excluded, such as the transverse vaginal septum, imperforate hymen, iatrogenic cervical injury or Müllerian malformation alone without obstructive outflow anomalies like didelphys, bicornuate, or septate uterus.
METHODS: The concordance between the surgically confirmed diagnosis and the pelvic ultrasound was reported in 27 of 29 women (93.1%). In contrast, only 24 of 29 cases were correctly diagnosed with MRI in this study (82.8%). This pilot study presents a comparison of two techniques, with a specific focus on obstructive Müllerian anomalies. The use of pelvic ultrasound not only assisted in our surgical practice but also significantly improved patient-doctor counseling.
CONCLUSIONS: In managing obstructive Müllerian abnormalities, 3D-enhanced conventional pelvic ultrasound was found effective in diagnosis and was comparable to MRI.

We present field-domain rapid-scan (RS) electron paramagnetic resonance (EPR) at 8.6T and 240GHz. To enable this technique, we upgraded a home-built EPR spectrometer with an FPGA-enabled digitizer and real-time processing software. The software leverages the Hilbert transform to recover the in-phase (I) and quadrature (Q) channels, and therefore the raw absorptive and dispersive signals, χ\' and χ\'\', from their combined magnitude (I2+Q2). Averaging a magnitude is simpler than real-time coherent averaging and has the added benefit of permitting long-timescale signal averaging (up to at least 2.5×106 scans) because it eliminates the effects of source-receiver phase drift. Our rapid-scan (RS) EPR provides a signal-to-noise ratio that is approximately twice that of continuous wave (CW) EPR under the same experimental conditions, after scaling by the square root of acquisition time. We apply our RS EPR as an extension of the recently reported time-resolved Gd-Gd EPR (TiGGER) [Maity et al., 2023], which is able to monitor inter-residue distance changes during the photocycle of a photoresponsive protein through changes in the Gd-Gd dipolar couplings. RS, opposed to CW, returns field-swept spectra as a function of time with 10ms time resolution, and thus, adds a second dimension to the static field transients recorded by TiGGER. We were able to use RS TiGGER to track time-dependent and temperature-dependent kinetics of AsLOV2, a light-activated phototropin domain found in oats. The results presented here combine the benefits of RS EPR with the improved spectral resolution and sensitivity of Gd chelates at high magnetic fields. In the future, field-domain RS EPR at high magnetic fields may enable studies of other real-time kinetic processes with time resolutions that are otherwise difficult to access in the solution state.

BACKGROUND: In recent years, there has been an increasing effort to take advantage of the potential use of low magnetic induction devices with less than 1 T, referred to as Low-Field MRI (LF MRI). LF MRI systems were used, especially in the early days of magnetic resonance technology. Over time, magnetic induction values of 1.5 and 3 T have become the standard for clinical devices, mainly because LF MRI systems were suffering from significantly lower quality of the images, e.g., signal-noise ratio. In recent years, due to advances in image processing with artificial intelligence, there has been an increasing effort to take advantage of the potential use of LF MRI with induction of less than 1 T. This overview article focuses on the analysis of the evidence concerning the diagnostic efficacy of modern LF MRI systems and the clinical comparison of LF MRI with 1.5 T systems in imaging the nervous system, musculoskeletal system, and organs of the chest, abdomen, and pelvis.
METHODS: A systematic literature review of MEDLINE, PubMed, Scopus, Web of Science, and CENTRAL databases for the period 2018-2023 was performed according to the recommended PRISMA protocol. Data were analysed to identify studies comparing the accuracy, reliability and diagnostic performance of LF MRI technology compared to available 1.5 T MRI.
RESULTS: A total of 1275 publications were retrieved from the selected databases. Only two articles meeting all predefined inclusion criteria were selected for detailed assessment.
CONCLUSIONS: A limited number of robust studies on the accuracy and diagnostic performance of LF MRI compared with 1.5 T MRI was available. The current evidence is not sufficient to draw any definitive insights. More scientific research is needed to make informed conclusions regarding the effectiveness of LF MRI technology.

Diagnostic imaging is essential in the diagnostic process of rheumatic diseases. Given the heterogeneity of this group of diseases and the tremendous impact of novel therapeutic options, guidelines and recommendations regarding the optimal choice of the most appropriate technique/s are continuously revised and radiologists should always be up-to-date. Last, because of the continuous technological innovations, we will assist to the progressive application of advanced techniques and tools in rheumatology.

UNASSIGNED: We aimed to integrate MR radiomics and dynamic hematological factors to build a model to predict pathological complete response (pCR) to neoadjuvant chemoradiotherapy (NCRT) in esophageal squamous cell carcinoma (ESCC).
UNASSIGNED: Patients with ESCC receiving NCRT and esophagectomy between September 2014 and September 2022 were retrospectively included. All patients underwent pre-treatment T2-weighted imaging as well as pre-treatment and post-treatment blood tests. Patients were randomly divided to training set and testing set at a ratio of 7:3. Machine learning models were constructed based on MR radiomics and hematological factors to predict pCR, respectively. A nomogram model was developed to integrate MR radiomics and hematological factors. Model performances were evaluated by areas under curves (AUCs), sensitivity, specificity, positive predictive value and negative.
UNASSIGNED: A total of 82 patients were included, of whom 39 (47.6 %) achieved pCR. The hematological model built with four hematological factors had an AUC of 0.628 (95%CI 0.391-0.852) in the testing set. Two out of 1106 extracted features were selected to build the radiomics model with an AUC of 0.821 (95%CI 0.641-0.981). The nomogram model integrating hematological factors and MR radiomics had best predictive performance, with an AUC of 0.904 (95%CI 0.770-1.000) in the testing set.
UNASSIGNED: An integrated model using dynamic hematological factors and MR radiomics is constructed to accurately predicted pCR to NCRT in ESCC, which may be potentially useful to assist individualized preservation treatment of the esophagus.