Sensitivity Of Magnetic Resonance Imaging Research Articles

Visualizing enterohepatic circulation in vivo by sensitive 19F MRI with a fluorinated ferrous chelate-based small molecule probe.

Enterohepatic circulation (EHC) is a critical biological process for the normal regulation of many endogenous biomolecules and the increased retention of various exogenous substances. The status of EHC is closely related to the ordinary functioning of several digestive organs. However, it remains a challenge to achieve in vivo real-time visualization of this process. Herein, we rationally design and synthesize a ferrous chelate, DO3A-Fe(II)-9F, with high fluorine content and favorable water solubility for visualizing EHC via19F magnetic resonance imaging (MRI). The assessments on imaging performance reveal an 18-time increase in signal intensity compared to the fluorinated ligand alone. This probe's capability of entering EHC via the mediation of organic anion transporting polypeptides (OATPs) is validated with ex vivo bio-distribution analysis and in vivo uptake-blocking imaging experiments, which allows short-time sensitive 19F MRI of EHC in healthy mice. Additionally, we illustrate its capacity for clearly imaging tampered EHC in the mice with inflammatory bowel diseases (IBD), drug-induced liver injury (DILI) or orthotopic hepatocellular carcinoma (HCC). These results illustrate the promising potential of this probe for in vivo visualization of EHC under different conditions, especially disease conditions, which is beneficial for the study, diagnosis, or even stratification of various diseases.

MRI in the evaluation of plantar plate disease: diagnostic value of the “stress test”

Abstract Introduction The plantar plate, also called the plantar ligament, is a fibrocartilaginous structure found in the metatarsophalangeal (MTP) and interphalangeal (IP) joints. Our study aimed to evaluate the role of magnetic resonance imaging (MRI) performed with the patient in the standard position or with joint hyperextension (the “stress test”, ST) in the study of plantar plate (PP) disease that involves metatarsophalangeal joints. Materials and methods All patients underwent forefoot MRI (Atroscan C, Esaote, Genoa, Italy), operating at 0.2 T. All patients first underwent a standard MRI examination (coronal T1 and T2 weighted image (WI) with fat suppression and axial and sagittal T2 WI); the examination was completed by performing a stress test (hyperextension of toes). The ST is an easy task to perform and is not time-consuming (requiring only one additional sagittal fast spin echo (FSE) T2-weighted MRI sequence; repetition time/ echo time (TR/TE): 3200/90 ms) for patients and operators. A 45°-dorsiflexion ST was performed for approximately 2.30 min, the time required to complete the sequence. No further diagnostic investigations were necessary; no patients underwent arthrography or arthro-MRI. The examinations were performed in a double-blind mode by two operators with proven experience in musculoskeletal radiology; no cases of intra-operator discordance were found. Results Twenty-five patients were recruited into our study over a 2-year period; 15 were positive for metatarsal pain and 10 were controls. Before treatment (surgery), all patients displaying symptoms underwent evaluation. As a result, the imaging features accurately represented the natural and actual conditions of the lesions. Among the symptomatic patients, 11 out of the 15 exhibited a PP tear or dysfunction in both the standard position and the ST. Additionally, two out of the 15 individuals displayed a tear in the ST alone, with no indication of it in the standard position. In contrast, two out of 15 patients showed no evidence of a PP tear in either the standard position or the ST. However, these two patients demonstrated dorsal subluxation during the ST, likely due to micro-instability resulting from PP failure. In the asymptomatic patients, nine out of the 10 individuals were found to be negative for PP dysfunction. Only one out of the 10 patients exhibited dorsal subluxation solely in the ST, indicative of plantar plate dysfunction, but no evidence of a tear in the PP. In the asymptomatic patients, standard MRI provided a specificity of 100% and a high negative predictive value (NPV) (90%), while the latter increased with the ST (specificity and NPV equal to 100%). In symptomatic patients, standard MRI gave a sensitivity of 75% when assessing a PP tear, which increased to 100% with the ST; the sensitivity of standard MRI the evaluation of MF subluxation was 60%, but it reached 100% with the ST. Conclusions In our study, by introducing the ST, the sensitivity in both the diagnosis of a PP tear and the evaluation of MTP subluxation reached 100% (a surgical assessment was performed on all positive patients for confirmation). Ultrasound has the advantage of being a non-invasive method. However, comparing the results of our study with the data available in the literature, ultrasound has a lower sensitivity and a negative predictive value. Also, ultrasound does not allow for the assessment of possible bone marrow oedema or the degree of concomitant arthritis. If other studies in the literature confirm these results, it will be possible to consider incorporating the ST into diagnostic practice in the future.

F18-DCFPyL PSMA-PET/CT Versus MRI: Identifying the Prostate Cancer Region Most at Risk of Radiation Therapy Recurrence for Tumor Dose Escalation.

Local recurrence of prostate cancer (PCa) after radiation therapy (RT) typically occurs at the site of dominant tumor burden, and recent evidence confirms that magnetic resonance imaging (MRI) guided tumor dose escalation improves outcomes. With the emergence of prostate-specific membrane antigen (PSMA) positron emission tomography (PET), we hypothesize that PSMA-PET and MRI may not equally depict the region most at risk of recurrence after RT. Patients with intermediate- to high-risk PCa and MRI plus PSMA-PET performed before RT were identified. The sextant most at risk of recurrence was defined as the pathologically dominant region with peak biopsy percentage core length involvement and any sextant with ≥ 40% percentage core length involvement (pathologic gross tumor volume [pGTV], per prior work). Imaging methods were reviewed independently to compare GTVs with pGTVs most at risk of recurrence. A paired chi-square test was employed for analysis. Eighty-eight patients (n = 88) were identified. Overall, there were no differences in the sensitivity of MRI and PSMA-PET for identifying the pGTV most at risk of recurrence. However, PSMA-PET demonstrated a trend of improved sensitivity for high-risk PCa compared with MRI (n = 46, 96% vs 87%, P = .06), while MRI outperformed PSMA-PET for the intermediate-risk group (n = 42, 93% vs 81%, P = .03). PSMA-PET showed lower specificity, misidentifying GTV in uninvolved pathologic sextants for 12% of intermediate-risk patients, whereas MRI was faultless (12% vs 0%, P = .03). MRI and PSMA-PET each misidentified uninvolved sextants for 9% of patients in the high-risk group. MRI demonstrates superior sensitivity in identifying the region most at risk of RT recurrence for intermediate-risk PCa, whereas PSMA-PET may add value for some high-risk patients. Informed by sextant biopsy information and MRI, clinicians should consider integrating PSMA-PET for patients with high-risk diseases when delineating GTVs.

Novel frequency selective B1 focusing passive lenz resonators for substantial MRI signal-to-noise ratio amplification

Objective.The need for increased sensitivity in magnetic resonance imaging (MRI) is crucial for its advancement as an imaging modality. The development of passive Lenz Resonators (LRs) for effective RF magnetic field (B1) focusing will improve MRI sensitivity via local amplification of MRI signal, thereby leading to more efficient diagnosis and patient treatment.Approach.While there are methods for amplifying the signal from specific nuclei in MRI, such as hyperpolarization, a general solution will be more advantageous and would work in combination with these preexisting methods. While the Lenz Lens proposed such a general solution based on Lenz's law and the reciprocity principle, it came at the cost of limited signal enhancement. In this work, the first-in-kind prototype LR was conceived and examined as a general frequency-selective passive flux-focusing element for significant MRI signal enhancement. A 3.0 T Philips Achieva MRI was used to compare the signal from a phantom in the presence of Lenz Lenses, LRs, and control trials with neither component.Main results.An MRI investigation demonstrated an experimental amplification of the signal-to-noise ratio up to 80% using an MRI insert of two coaxial LRs due to superior B1focusing. The resonators displayed consistent amplification, nearly independent of theirx-position within the MRI bore.Significance.This behavior demonstrates the feasibility of imaging large objects of varying shapes without penalties for signal amplification using LRs. The LRs versatility in geometrical design and consistent signal amplifying abilities between pulse sequences should allow for the development of LRs suitable for most commonly used MRI setups.

MRI without contrast enhancement is a highly accurate method of imaging insulinoma

BACKGROUND: According to the literature, there are contradictory results regarding the diagnostic accuracy of magnetic resonance imaging (MRI) without contrast enhancement (CE) in insulinoma, and studies that analyze the factors influencing the obtaining of false negative results have not been described.AIM: Evaluation of the operational characteristics of MRI imaging of insulinoma without CE.MATERIALS AND METHODS: Imaging studies of the abdominal cavity and retroperitoneal space were performed in patients with suspected nondiabetic hypoglycemia (NDH): MRI without CE (index test) and CT with CE (first row reference test). Ultrasound examination was used as a reference test of the second row, and arteriostimulated venous blood sampling was used in the third row. The diagnosis of NDH and insulinoma was established based on the detection of hyperinsulinemic hypoglycemia during laboratory examination and confirmation of the presence of a pancreatic tumor.RESULTS: 125 patients with insulinoma and 55 patients with other causes of NDH were included. The sensitivity of MRI without CE in the diagnosis of insulinoma was 94%, 95% CI [89%; 98%], specificity — 98%, 95% CI [90%; 100%], prognostic value of a positive result — 99%, 95% CI [95%; 100%], prognostic value of a negative result is 87%, 95% CI [76%; 94%]. The Kappa index of agreement with the final diagnosis was 0.886 (95% CI [0.814; 0.958]), which corresponds to excellent agreement, with CT — 0.750 (95% CI [0.651; 0.850]), which corresponds to significant agreement.In a comparative analysis of the tomographic and pathomorphological characteristics of insulinoma, in cases with divergent results when using MRI without CE and CT with CE, significant differences in structure, shape, contour features, localization and degree of malignancy of the tumor, as well as the structure of its surrounding parenchyma were not revealed.In the presented sample, the insulinoma has a median size of 14–15 mm with the median optical density in the native phase of CT 42–44 units.H, hyperintensivity on T2-weighted MRI images in 89%, 95% CI [78%; 95%] cases and low Grade 1 malignancy in 70%, 95% CI [56%; 81%] cases.CONCLUSION: CT with CE and MRI without CE are characterized by significant agreement in the diagnosis of insulinoma. In this regard, as well as due to the lack of radiation exposure and the strict need for contrast agents, MRI without CE can be recommended as a first-line method on a par with abdominal ultrasound and CT with CE to detect insulinoma.

Prenatal cfDNA Sequencing and Incidental Detection of Maternal Cancer

BackgroundCell-free DNA (cfDNA) sequence analysis to screen for fetal aneuploidy can incidentally detect maternal cancer. Additional data are needed to identify DNA-sequencing patterns and other biomarkers that can identify pregnant persons who are most likely to have cancer and to determine the best approach for follow-up.MethodsIn this ongoing study we performed cancer screening in pregnant or postpartum persons who did not perceive signs or symptoms of cancer but received unusual clinical cfDNA-sequencing results or results that were nonreportable (i.e., the fetal aneuploidy status could not be assessed) from one of 12 different commercial laboratories in North America. We used a uniform cancer-screening protocol including rapid whole-body magnetic resonance imaging (MRI), laboratory tests, and standardized cfDNA sequencing for research purposes with the use of a genomewide platform. The primary outcome was the presence of cancer in participants after the initial cancer-screening evaluation. Secondary analyses included test performance.ResultsCancer was present in 52 of the 107 participants in the initial cohort (48.6%). The sensitivity and specificity of whole-body MRI in detecting occult cancer were 98.0% and 88.5%, respectively. Physical examination and laboratory tests were of limited use in identifying participants with cancer. Research sequencing showed that 49 participants had a combination of copy-number gains and losses across multiple (≥3) chromosomes; cancer was present in 47 of the participants (95.9%) with this sequencing pattern. Sequencing patterns of cfDNA in which there were only chromosomal gains (multiple trisomies) or only chromosomal losses (one or more monosomies) were found in participants with nonmalignant conditions, such as fibroids.ConclusionsIn this study, 48.6% of participants who received unusual or nonreportable clinical cfDNA-sequencing results had an occult cancer. Further study of DNA-sequencing patterns that are suggestive of occult cancer during prenatal screening is warranted. (Funded by the NIH Intramural Research Programs; ClinicalTrials.gov number, NCT04049604.)

Diagnostic Accuracy of Magnetic Resonance Imaging in the Diagnosis of Anterior Cruciate Ligament Injury taking Arthroscopy as Gold Standard

Objective: To determine the diagnostic accuracy of magnetic resonance imaging (MRI) in the diagnosis of anterior cruciate ligament injury, using arthroscopy as the gold standard. Methodology: It was a descriptive, cross-sectional study that included 154 patients with suspected anterior cruciate ligament injury from the Department of Orthopaedics, Imran Idrees Teaching Hospital, Sialkot. All patients underwent arthroscopy and the presence or absence of ACL (anterior cruciate ligament) injury was noted. MRI findings were compared with arthroscopy findings. Results: Among the 94 MRI-positive patients, 88 (True Positive) had ACL injury while 06 (False Positive) had no ACLinjury on arthroscopy. Out of 60 MRI-negative patients, 08 (False Negative) had ACL injury on arthroscopy while 52 (True Negative) had no ACL injury. Overall sensitivity, specificity, PPV (positive predictive value), NPV (negative predictive value) and DA (diagnostic accuracy) of MRI in the diagnosis of ACLinjury, taking arthroscopy as the gold standard was 91.67%, 89.66%, 83.62%, 86.67% and 90.91% respectively. Conclusion: The study concluded that MRI is a very sensitive and precise diagnostic modality. It has significantly improved the ability to diagnose ACL injuries, allowing for more accurate and reliable assessments. Additionally, the use of MRI has been instrumental in reducing the number of purely diagnostic arthroscopies, thereby minimizing the need for invasive procedures and enhancing patient care.

Advancing Diagnostics: The Role of Ultrasound and MR Imaging in Evaluating Musculotendinous Pathologies of the Shoulder Joint – A Comprehensive Literature Review

Musculotendinous pathologies of the shoulder joint are a common source of pain and functional impairment, often requiring precise imaging for accurate diagnosis and management. This review explores the roles of ultrasound (US) and magnetic resonance imaging (MRI) in evaluating these conditions, focusing on their diagnostic strengths, limitations, and clinical applications. Ultrasound offers dynamic, real-time assessment with high accuracy for superficial structures, making it a cost-effective option for evaluating rotator cuff tears and tendinopathies. MRI, on the other hand, is the gold standard for comprehensive imaging of deep soft tissues, labral injuries, and subtle intra-articular abnormalities. Recent advances in both modalities, including AI-powered ultrasound and faster MRI sequences, have enhanced diagnostic capabilities. This review synthesizes evidence from the past decade, comparing the sensitivity, specificity, and cost-effectiveness of US and MRI while discussing scenarios where their integration can provide the most benefit. The findings emphasize the need for modality selection tailored to clinical presentations, the expertise of practitioners, and healthcare resource availability. Future research should aim to standardize imaging protocols and explore innovative multimodal approaches to improve diagnostic accuracy further.

Comparative Study of MRI and Ultrasound in Diagnosing Musculoskeletal Soft Tissue Tumours

ABSTRACT Background: Musculoskeletal soft tissue tumors represent a complex category of neoplasms with varied biological behavior and prognosis. Accurate diagnosis and characterization of these tumors are essential for appropriate management. Magnetic Resonance Imaging (MRI) and Ultrasound (US) are commonly employed imaging modalities for evaluating soft tissue masses. Materials and Methods: This comparative study included 100 patients with clinically suspected musculoskeletal soft tissue tumors. Patients underwent both MRI and Ultrasound evaluations. The imaging findings were compared with histopathological results, which served as the gold standard. Diagnostic parameters including sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for both MRI and Ultrasound. Results: Out of 100 patients, 70 cases were diagnosed as malignant and 30 as benign on histopathology. MRI correctly identified 68 malignant and 28 benign cases, with a sensitivity of 97.1%, specificity of 93.3%, PPV of 95.8%, and NPV of 96.6%. Ultrasound accurately diagnosed 60 malignant and 25 benign cases, with a sensitivity of 85.7%, specificity of 83.3%, PPV of 90.9%, and NPV of 76.9%. MRI demonstrated superior diagnostic accuracy compared to Ultrasound, particularly in identifying malignancies. Conclusion: MRI is a more reliable imaging modality compared to Ultrasound for diagnosing musculoskeletal soft tissue tumors, particularly in distinguishing between benign and malignant lesions. The higher sensitivity and specificity of MRI suggest its preference as the first-line imaging technique in clinical practice for these conditions.

Utilization of nanomaterials in MRI contrast agents and their role in therapy guided by imaging.

Magnetic Resonance Imaging (MRI) is a globally acknowledged diagnostic procedure particularly recognized for its superior soft tissue contrast, high-resolution imaging, and non-ionizing radiation properties, making it an indispensable tool in the medical field. However, to optimize MRI's sensitivity and specificity towards certain diseases, use of contrast agents becomes necessary. Recent developments focus on nanomaterial-based MRI contrast agents to improve diagnostic accuracy and image quality. This review highlights advancements in such agents, including metal oxide nanoparticles, carbon-based materials, gold nanoparticles, and quantum dots. It discusses their roles in MRI-guided therapies like targeted drug delivery, hyperthermia, radiation therapy, photodynamic therapy, immunity-boosting therapy, and gene therapy. Insights into the future potential of MRI contrast agents in imaging medicine are also provided.

The role of 18F-FDG PET/MRI in assessing pathological complete response to neoadjuvant chemotherapy in patients with breast cancer: a systematic review and meta-analysis

Background and aimThe present study aimed to evaluate the use of 18F-2-[18F]-fluoro-2-deoxy-d-glucose (FDG) PET/MRI (Positron emission tomography-computed tomography) in predicting the pathological response to neoadjuvant chemotherapy (NAC) in patients with breast cancer (BC) compared to the use of MRI (Magnetic Resonance Imaging) alone.MethodsWe searched numerous databases, including PubMed, Scopus, Embase, and Science Direct, using curated keywords. The variance of each study was determined using the binomial distribution, and STATA version 14 was used to analyze the data by performing random-effect models. Additionally, we calculated study heterogeneity using the chi-squared test and I2 index and utilized funnel plots and Egger tests to assess publication bias.ResultsThe current investigation analyzed 239 patients from six published studies. The pooled estimated sensitivity and specificity of 18F-FDG PET/MRI was 0.91 (95% CI = 0.90 to 0.92, I2 = 100% and P = 0.000) and 0.62 (95% CI = 0.53 to 0.72, I2 = 99.8% and P = 0.000), respectively. Pooled sensitivity and specificity of MRI were 0.78 (95%CI = 0.59 to 0.96, I2 = 100% and P = 0.000) and 0.56 (95%CI = 0.33 to 0.80, I2 = 99.8% and P = 0.000), respectively.ConclusionsBased on our findings, the combined form of 18F-FDG PET/MRI imaging is more sensitive and specific than MRI alone for predicting response to NAC in BC patients.

Diagnostic Accuracy of Magnetic Resonance Imaging in the 120° Flexed-Knee Position for Detecting and Classifying Meniscal Ramp Lesion

Background: Detection of meniscal ramp lesions concomitant with anterior cruciate ligament (ACL) injury using conventional magnetic resonance imaging (MRI) has low sensitivity, and these lesions are currently difficult to diagnose preoperatively. Purpose/Hypothesis: The purpose of this study was to assess the accuracy of MRI in detecting the presence of meniscal ramp lesions in the 120° flexed-knee position compared with that in the near–extended-knee position. It was hypothesized that the diagnostic performance of MRI in the 120° flexed-knee position would be better than that in the extended-knee position. Study Design: Cohort study (Diagnosis); Level of evidence, 2. Methods: This retrospective study of prospectively collected data between February 2019 and January 2024 included 154 consecutive patients undergoing ACL reconstruction. All patients underwent 3-T MRI examination in the near extended- and 120° flexed-knee positions preoperatively. The presence and Thaunat classification of ramp lesions were separately detected on each MRI scan and confirmed via arthroscopy during ACL reconstruction. Diagnostic sensitivity, specificity, and conditional relative odds ratios for detecting ramp lesions and the classification accuracy were compared between 2 MRI modalities. The accuracies of these MRI scans in acute and chronic cases were also evaluated. Results: This study included 154 patients (79 male and 75 female; mean age, 29.0 ± 14.2 years). A total of 62 ramp lesions (40.3%) were observed on arthroscopy. The sensitivity and specificity of MRI in near extension were 69.4% and 77.2%, respectively, and those in flexion were 91.9% and 94.6%, respectively, with significant superiority in MRI at knee flexion (P = .003 and P < .001, respectively). The conditional relative odds ratio between the MRI examinations at these 2 positions was 10.3 (95% CI, 4.82-21.8). The classification accuracy of MRI in flexion was significantly higher than that of MRI in near extension (accuracy, 49 vs 11; P < .001). The diagnostic accuracy of MRI in the 120° flexed-knee position was significantly higher than that in the near–extended-knee position in the acute cases (P < .05); however, no significant differences were observed in the chronic cases. Conclusion: The diagnostic accuracy of MRI in the 120° flexed-knee position for detecting and classifying meniscal ramp lesions was superior to that of MRI in the near–extended-knee position.

Diagnostic accuracy of magnetic resonance imaging (MRI) for symptomatic knee osteoarthritis: a scoping review.

In recent years, significant progress in the diagnosis of knee osteoarthritis (OA) has been made due to advancements in imaging techniques, especially magnetic resonance imaging (MRI). However, the diagnostic accuracy of MRI for knee OA lacks agreement in the literature due to limitations such as heterogeneous reference standards and suboptimal methodological assessment tools. This scoping review systematically collated the literature on the accuracy of MRI in diagnosing symptomatic knee OA and evaluated its methodological quality using a novel tool. A comprehensive search was conducted across seven electronic databases to identify systematic reviews, with or without meta-analyses, published until May 30, 2024. Selected articles were systematic reviews on test accuracy of MRI for knee OA, whose methodological quality was assessed using a tailored version of the A Measurement Tool to Assess Systematic Reviews (AMSTAR) 2 tool, and the test accuracy performance summarized. The search yielded 8,586 records of which 73 full-text articles were assessed for eligibility. We included 3 systematic reviews with a total of 99 original studies (7,530 participants). The methodological quality assessment of the reviews revealed common deficiencies in research questions and inclusion criteria components (2/3, 66.7%), protocol registration (2/3, 66.7%), use of statistical methods (1/3, 33.3%), and risk of bias assessment (2/3, 66.7%). The reference standards used were histology (1/3, 33.3%), radiography (1/3, 33.3%), computed tomography (1/3, 33.3%), clinical evaluation (1/3, 33.3%) and direct visual inspection (1/3, 33.3%), open surgery (1/3, 33.3%) and arthroscopy (3/3, 100%). In two reviews with meta-analysis the accuracy of MRI was: sensitivity 61% [95% confidence interval (CI), 53-68%] and specificity 82% (95% CI, 77-87%) (low methodological quality); and sensitivity 74% (95% CI, 71-77%) and specificity 95% (95% CI, 94-95%) (high methodological quality). In the third systematic review, without meta-analysis, the MRI sensitivity and specificity ranged from 26% to 96% and from 50% to 100%, respectively (critically low methodological quality). This scoping review highlights the heterogeneity and gaps in methodological quality of the literature regarding the accuracy of MRI in diagnosing knee OA. Our adaptation of AMSTAR 2 will help to ensure systematic reviews of diagnostic tests are assessed more effectively and reliably. There is a need for standardization in future studies and reviews to strengthen the evidence base for the use of MRI as a diagnostic tool for knee OA.

Brain morphometrics correlations with age among 352 participants imaged with both 3T and 7T MRI: 7T improves statistical power and reduces required sample size.

Magnetic resonance imaging (MRI) at 7 Telsa (7T) has superior signal-to-noise ratio to 3 Telsa (3T) but also presents higher signal inhomogeneities and geometric distortions. A key knowledge gap is to robustly investigate the sensitivity and accuracy of 3T and 7T MRI in assessing brain morphometrics. This study aims to (a) aggregate a large number of paired 3T and 7T scans to evaluate their differences in quantitative brain morphological assessment using a widely available brain segmentation tool, FreeSurfer, as well as to (b) examine the impact of normalization methods for subject variability and smaller sample sizes on data analysis. A total of 452 healthy participants aged 29 to 68 were imaged at both 3T and 7T. Structural T1-weighted magnetization-prepared rapid gradient-echo (MPRAGE) images were processed and segmented using FreeSurfer. To account for head size variability, the brain volumes underwent intracranial volume (ICV) correction using the Residual (regression model) and Proportional (simple division to ICV) methods. The resulting volumes and thicknesses were correlated with age using Pearson correlation and false discovery rate correction. The correlations were also calculated in increasing sample size from 3 to the whole sample to estimate the sample size required to detect aging-related brain variation. 352 subjects (210 females) passed the image quality control with 100 subjects excluded due to excessive motion artifacts on 3T, 7T, or both. 7T MRI showed an overall stronger correlation between morphometrics and age and a larger number of significantly correlated brain volumes and cortical thicknesses. While the ICV is consistent between both field strengths, the Residual normalization method shows markedly higher correlation with age for 3T when compared with the Proportional normalization method. The 7T results are consistent regardless of the normalization method used. In a large cohort of healthy participants with paired 3T and 7T scans, we compared the statistical performance in assessing age-related brain morphological changes. Our study reaffirmed the inverse correlation between brain volumes and cortical thicknesses and age and highlighted varying correlations in different brain regions and normalization methods at 3T and 7T. 7T imaging significantly improves statistical power and thus reduces required sample size.

Diagnostic accuracy of imaging modalities for detection of spinal metastases: a systematic review and meta-analysis.

Detecting spinal metastases is highly relevant in patients with oncological disorders as it can affect the staging and treatment of their disease. We aimed to evaluate the diagnostic performance of computed tomography (CT), magnetic resonance imaging (MRI), FDG positron emission tomography (PET)/CT, bone scintigraphy (BS), and single-photon emission computed tomography (SPECT) for spinal metastases detection. Medline, EMBASE, and Web of Science were systematically searched until March 2024 for diagnostic accuracy studies on spinal metastases detection (PROSPERO-registration: CRD42024540139). Data extraction and quality assessment using the QUADAS-2 tool were performed by two independent reviewers. Using bivariate random effects modeling, pooled sensitivities, specificities, and diagnostic odds ratios (DOR) were calculated, and hierarchical summary operating curves were constructed. Twenty-five studies (49 datasets), encompassing 3102 patients were included. Per-patient pooled sensitivities of CT, MRI, PET/CT, BS and SPECT were 70%, 93%, 82%, 75%, and 84%, respectively. Pooled specificities were 74%, 85%, 75%, 92%, and 81%, respectively. Per-lesion pooled sensitivities of CT, MRI, PET/CT, BS and SPECT were 76%, 91%, 92%, 77%, and 92%, respectively. Pooled specificities were 91%, 94%, 85%, 52%, and 86%, respectively. MRI had the highest DOR in per patient and lesion analyses. MRI had highest diagnostic accuracy for spinal metastases detection on patient and lesion level, suggesting a broader use in addition to the routine staging CT, at least in patients at high risk and where the detection of a spinal metastasis could alter therapy decisions. Herein, results should be considered with the limitations of each modality.

Assessment of sub clinical right ventricular ischemia using oxygen sensitive cardiac magnetic resonance imaging in patients with systemic sclerosis: mechanistic insights from advanced cardiac imaging

Abstract Background Cardiac involvement in Systemic Sclerosis (SSc) is common, with manifestations ranging from subclinical to life-threatening 1. Cardiopulmonary complications, including, right ventricular (RV) dysfunction is the leading cause of SSc-related mortality2. Pulmonary arterial hypertension (PAH) occurs in 8-12% of SSc patients and remains a leading cause of death, with a 3-year survival rate around 50%2. The progressive decline in RV function in PAH is often attributed to RV ischemia3. Oxygen Sensitive Cardiac Magnetic Resonance imaging (OS-CMR) has been previously used by our group to assess RV myocardial oxygenation in patients with PAH3, including SSc-associated PAH 3. The objective of this study was to use OS-CMR to assess RV myocardial oxygenation in SSc patients prior to the onset of PAH. Methodology In this prospective, multicentre study, three study groups were established. Group 1 comprised SSc patients without PAH or known cardiac disease. Group 2 included stable PAH patients confirmed by right heart catheterization, matched for age and sex, but without SSc. Group 3 comprised healthy normal volunteers (NV), matched for age and sex. All patients underwent a 3T CMR which included: cine images, rest cine OS-CMR, stress cine OS-CMR, native T1 mapping, stress perfusion, and late gadolinium enhancement (LGE). The primary outcome was change in inferior RV myocardial signal intensity (SI) in diastole, measured by the change in OS-CMR between rest and stress within each group. Two experienced independent reviewers performed the CMR analysis with an inter-assessor correlation coefficient of 0.8, 95% Cl [0.3, 0.9]. Results A total of 44 patients were enrolled. Of these, n=26 group 1 (SSc), n=8 group 2 (PAH), n=10 group 3 (NV). Study results are listed in Table 1. Mean age within the SSc, PAH, and NV groups were 59±10, 67±12 and 57 ±7 years respectively (p=0.482). The RV OS-CMR SI was significantly lower in the SSc group when compared to the NV group (p=0.017). In contrast, there was no significant difference between the PAH and SSc groups (p=0.426), indicating a similar degree of RV ischemia in the established PAH patients and the SSc patients. All SSc patients exhibited inferior and anterior RV insertion fibrosis, with no perfusion defects noted. Five (19%) of SSc patients presented with LGE hyperenhancement in the LV. Eighteen (69%) of SSc patients obtained at least 1 abnormal T1 mapping segment in the LV. Conclusion SSc patients without overt PAH had a similar degree of RV ischemia when compared to patients with overt PAH from other causes. Our findings imply that in SSc, RV adverse effects occur prior to the onset of PAH, and that this effect is mediated by RV ischemia secondary to changes in the microvasculature. Our findings may have screening and/or therapeutic implications.

Neoadjuvant chemoradiation for down staging of locally-advanced rectal cancer, and assessment of clinical response with digital rectal examination, magnetic resonance imaging and colonoscopy

Background: In this era of total neoadjuvant treatment (TNT) followed by rectal preservation non-operative management (NOM) or wait and watch (WW) approach for non-metastatic locally-advanced rectal cancer (LARC), reliable and reproducible response evaluation to neoadjuvant therapies forms the cornerstone. Through this study, we try to evaluate clinical response of locally-advanced rectal cancer to neoadjuvant chemoradiation (CRT) in terms of downstaging and total mesorectal excision (TME), and the accuracy of digital rectal examination (DRE), magnetic resonance imaging (MRI) and colonoscopy in the assessment of clinical response to neoadjuvant CRT. Methods: Histologically proven locally advanced rectal adenocarcinoma patients, after pretreatment evaluation, were considered for neoadjuvant chemoradiation, i.e., intensity-modulated radiation therapy (IMRT) with 5-fluorouracil (5-FU) and leucovorin-based concurrent chemotherapy. Patients were evaluated 6-8 weeks after completion of CRT and clinical response assessed by means of DRE, colonoscopy and MRI of pelvis. Following surgery, pathological response was assessed on the final histopathological examination (HPE). Results: Twenty-two patients were accrued for this protocol, of which, 15 (68.2%) were male and 7 (31.8%) were female. Downstaging and TME was achieved in 90.9% of the patients. The sensitivity of DRE, colonoscopy and MRI to detect a complete response was 66.67% and specificity was 94.74%. There were no severe toxicities or deaths reported. Conclusions: Neoadjuvant concurrent chemoradiotherapy with bolus 5-FU and leucovorin is an accepted modality of treatment for locoregionally-advanced rectal cancer, which offers higher rates of downstaging and TME. Digital rectal examination, colonoscopy and MRI together can be reliably used to assess response following neoadjuvant CRT.

Correlation between magnetic resonance imaging and arthroscopic findings in superior labral from anterior to posterior injuries of shoulder joint

Background: The aim of our study was to identify the accuracy of the magnetic resonance imaging (MRI) in detecting superior labral from anterior to posterior (SLAP) lesions when compared to arthroscopic findings, considering arthroscopy as the gold standard. Methods: This is a retrospective study conducted between January 2015 to July 2021 that focuses on SLAP lesions to evaluate the accuracy of its magnetic resonance imaging (MRI) reporting. All patients who had shoulder arthroscopy were included, and their intra-operative pathology was recorded and compared to their pre-operative MRI reports. Accuracy was assessed by calculating the sensitivity and specificity of MRI in comparison to the standard shoulder arthroscopy. Results: 60 patients were included in the study. In diagnosing SLAP lesions this study showed that MRI was 54% sensitivity, 67% specificity with 79% positive predictive value and 39% negative predictive value. Accuracy was found to be 55%. Conclusions: In this study, the MRI did not detect SLAP lesions at a rate as high as arthroscopy, which is considered the gold standard. When performing arthroscopy, it is important to be diligent in detecting actual SLAP lesions that may not have been identified by traditional MRI scans.

Evaluation of the reliability and accuracy of MRI for the diagnosis of meniscal ramp lesions.

Meniscal ramp lesions are a special type of meniscal injury that affects the periphery of the posterior horn of the medial meniscus and/or its meniscocapsular attachments, strongly associated with anterior cruciate ligament (ACL) tears. Due to their location, these lesions can be missed arthroscopically so it is essential to diagnose them on preoperative magnetic resonance imaging (MRI). To evaluate the accuracy of MRI in detecting meniscal ramp lesions in patients with ACL tears using arthroscopy as the reference standard. Two musculoskeletal radiologists, blinded to the surgical findings, retrospectively and independently evaluated 106 knee MRI scans for the presence of meniscal ramp lesions in non-consecutive patients who underwent arthroscopic ACL reconstruction between January 2019 and July 2022 by a single surgeon at one institution. Having arthroscopy as reference, the diagnostic sensitivity and specificity as well as the positive and negative predictive values (PPV/NPV) of the MRI scans were calculated. Cohen's kappa coefficient was used to test inter-observer reliability. A P value <0.05 was considered statistically significant. In the study group of 106 patients (72 men, 34 women; mean age = 33.84 ±13.12 years), 76 had an arthroscopy-confirmed meniscal ramp lesion, while 30 did not. The sensitivity and specificity of MRI for the detection of meniscal ramp lesion were 88% and 87%, respectively. The PPV and NPV were 94% and 74%, respectively. Inter-rater reliability was excellent (k = 0915). This study demonstrates that MRI can accurately detect meniscal ramp lesions.

Upfront Thoracic Magnetic Resonance Imaging for the Evaluation of Thymic Lesions to Reduce Non-Therapeutic Diagnostic Thymectomy: A Narrative Review.

Background: Thymic pathologies represent the most common lesions of the anterior mediastinum. They may be classified as malignant or benign. Current diagnostic pathways recommend an initial assessment with computed tomography (CT) imaging to delineate potentially malignant thymic lesions. Despite this, high rates of non-therapeutic thymectomy continue to be observed. This carries with it significant anaesthetic, operative, and post-operative risks, in addition to healthcare costs. Consequently, there is a growing interest in magnetic resonance imaging (MRI) as a primary diagnostic modality for lesions of the anterior mediastinum. This narrative review outlines the current approaches to the evaluation of thymic lesions, with a discussion of the strengths and limitations of CT and MRI imaging modalities. It also evaluates the current discourse on the use of upfront MRI for thymic and anterior mediastinal lesion assessment. Methods: A narrative review was performed following a search on the Medline database. Articles that were evaluated had explored the role of MRI on the evaluation of thymic and anterior mediastinal lesions. Results: Current work-up for thymic and anterior mediastinal lesions are highly variable and centre around the use of CT. Upfront MRI demonstrates a similar accuracy to CT for various thymic and anterior mediastinal pathologies; however, the efforts to integrate this approach into routine practice remain in their infancy, with no standardised guidelines that exist. Conclusions: This narrative review demonstrates that there is a paucity of evidence relating to the sensitivity and specificity of MRI compared to CT for thymic lesion analysis and their subsequent relationship with non-therapeutic thymectomy. Future prospective trials to assess the role of MRI in thymic lesion determination are required to understand whether MRI can more accurately characterise these lesions to reduce non-therapeutic thymectomy. Additionally, further research efforts are required to characterise best-practice methods for integrating MRI into diagnostic pathways for these lesions in a cost-effective and resource-conscious manner.