Accuracy Of Magnetic Resonance Imaging Research Articles

Motion and magnetic field inhomogeneity correction techniques for chemical exchange saturation transfer (CEST) MRI: A contemporary review.

Chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) has emerged as a powerful imaging technique sensitive to tissue molecular composition, pH, and metabolic processes in situ. CEST MRI uniquely probes the physical exchange of protons between water and specific molecules within tissues, providing a window into physiological phenomena that remain invisible to standard MRI. However, given the very low concentration (millimolar range) of CEST compounds, the effects measured are generally only on the order of a few percent of the water signal. Consequently, a few critical challenges, including correction of motion artifacts and magnetic field (B0 and B1 +) inhomogeneities, have to be addressed in order to unlock the full potential of CEST MRI. Motion, whether from patient movement or inherent physiological pulsations, can distort the CEST signal, hindering accurate quantification. B0 and B1 + inhomogeneities, arising from scanner hardware imperfections, further complicate data interpretation by introducing spurious variations in the signal intensity. Without proper correction of these confounding factors, reliable analysis and clinical translation of CEST MRI remain challenging. Motion correction methods aim to compensate for patient movement during (prospective) or after (retrospective) image acquisition, reducing artifacts and preserving data quality. Similarly, B0 and B1 + inhomogeneity correction techniques enhance the spatial and spectral accuracy of CEST MRI. This paper aims to provide a comprehensive review of the current landscape of motion and magnetic field inhomogeneity correction methods in CEST MRI. The methods discussed apply to saturation transfer (ST) MRI in general, including semisolid magnetization transfer contrast (MTC) and relayed nuclear Overhauser enhancement (rNOE) studies.

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

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. 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. Cohort study (Diagnosis); Level of evidence, 2. 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. 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. 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.

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.

Is Trochlear Dysplasia Associated with a High Prevalence of Repaired Anterior Medial Portal Lesions in Anterior Cruciate Ligament-Deficient Knees?

Abstract Introduction Meniscal tears, especially in the medial meniscus, are common in anterior cruciate ligament (ACL) injuries. Repaired anterior medial portal (RAMP) lesions, specific meniscal injuries associated with ACL ruptures, affect the peripheral attachment of the posterior horn of the medial meniscus. While the relationship between femoral trochlear morphology and ACL tears is established, its association with RAMP lesions remains unexplored. This study investigates the association between femoral trochlear morphology and RAMP lesions in ACL-deficient knees using magnetic resonance imaging (MRI) and evaluates MRI's accuracy against arthroscopy. Methods This hospital-based, cross-sectional observational study was conducted in a tertiary care center over 18 months. It included 126 adult patients who underwent arthroscopic ACL reconstruction and had preoperative MRI. Variables included age, gender, body mass index, trauma nature, and various MRI parameters, including femoral trochlear morphology and presence of RAMP lesions. MRI findings were compared to arthroscopic findings to evaluate diagnostic accuracy. Results RAMP lesions were detected in 21 participants (16.7%) via MRI and 28 participants (22.2%) via arthroscopy. MRI showed 71.4% sensitivity and 99.0% specificity for detecting RAMP lesions. No significant association was found between femoral trochlear morphology and RAMP lesions. However, medial tibial slope (TS) and posterior medial tibial bone edema (PMTBE) were significantly associated with RAMP lesions. The agreement between MRI and arthroscopy was high (Cohen's kappa = 0.773, p &lt; 0.001). Conclusion This study found no significant association between femoral trochlear morphology and RAMP lesions in ACL-deficient knees. Instead, medial TS and PMTBE were significant predictors. MRI proved to have high specificity but moderate sensitivity compared to arthroscopy.

Primary Site Influences the Ability of Magnetic Resonance Imaging to Assess Cartilage Invasion in Advanced Laryngeal Cancer.

Accurate staging of advanced laryngeal cancer is important, as treatment can vary significantly between larynx preservation and total laryngectomy. The purpose of this study was to evaluate the accuracy of magnetic resonance imaging (MRI) in assessing features of T4a disease in locally advanced laryngeal cancer and determine if primary site played a role in the accuracy of MRI in this setting. A retrospective cohort study of patients undergoing a total laryngectomy in a tertiary referral center for head and neck cancer over a 10-year time period was carried out. Patients met inclusion criteria if they underwent a primary total laryngectomy for squamous cell carcinoma (SCC) of the larynx during the study period. Data collected included basic demographic data, primary tumor subsite, and clinical and pathological staging. The predictive ability of MRI on outer thyroid cortex invasion, extralaryngeal extension, and overall T4a stage was analyzed with receiver operating characteristics analysis. Analysis was compared to histological data on outer thyroid cortex invasion, extralaryngeal extension, and histological T4a stage. A total of 112 patients met inclusion criteria. The mean age of the cohort was 65.1. Glottic primary subsite was associated with a statistically significant elevated risk for histological outer cortex erosion (p = 0.006), but MRI demonstrated worse sensitivity in detecting this outer cortex invasion in glottic primaries(p = 0.002). Glottic primaries tumors display an increased likelihood of thyroid cartilage invasion, however, MRI demonstrates a poorer sensitivity for detecting these features. Level 3 Laryngoscope, 2024.

Assessment of chemical-shift and diffusion-weighted magnetic resonance imaging in differentiating malignant and benign vertebral lesions in oncologic patients. A single institution experience.

To analyze the contribution of two non-standard magnetic resonance imaging (MRI) techniques the chemical-shift image (CSI), and diffusion-weighted imaging (DWI) in distinguishing malignant and benign vertebral bone marrow lesions (VBMLs). Conventional spine MRI protocol, followed by CSI and DWI was performed with a 1.5 T system on 102 oncologic patients between January 2020 and December 2023. From the identified 325 VBMLs, 102 representative lesions (one per patient) were selected. VBMLs were divided into malignant (n = 74) and benign (n = 28) based on histopathology, or imaging follow-up. The quantitative parameters for VBMLs assessment were signal intensity ratio (SIR) derived from CSI and apparent diffusion coefficient (ADC) derived from DWI. The malignant VBMLs had significantly higher SIR values (p < 0.05) and lower ADC values compared to benign VBMLs (p < 0.05). The area under the curve (AUC) was 0.953 (p < 0.001) for SIR, and 0.894 for ADC (p < 0.001) (cut-off at > 0.82, and ≤ 1.57x10-3 mm2/s, respectively). The sensitivity and specificity for SIR were 93.6%, and 88.5%, while for ADC were 88.2% and 92.3% (respectively). The combined use of SIR and ADC improved the diagnostic accuracy to AUC of 0.988 (p < 0.001, cut-off at > 0.19), sensitivity, and specificity of 100.0% and 90.9% (respectively). Quantitative parameters, SIR and ADC, derived from two non-standard MRI techniques, CSI, and DWI, showed diagnostic strength in differentiating malignant and benign VBMLs. Combining both methods can further enhance the diagnostic performance and accuracy of spine MRI in clinical practice.

Generation of a Human Induced Pluripotent Stem Cell Line Expressing a Magnetic Resonance Imaging Reporter Gene.

The objective of the current study is to develop a new method for tracking transplanted human induced pluripotent stem cells-derived cardiomyocytes (hiPSC-CMs) using magnetic resonance imaging (MRI). The CRISPR/dCas9 activation system is employed to overexpress ferritin heavy chain (FHC) in hiPSC-CMs. The mRNA and protein expression of FHC in hiPSC and hiPSC-CMs significantly increased after transfection. Iron chloride does not affect the cell viability in a concentration range from 0 to 2000 µm. hiPSCs overexpressing FHC (hiPSC- FHCOE) and hiPSC-CMs overexpressing FHC (hiPSC-CM-FHCOE) significantly enhanced cellular uptake of iron chloride but with no changes in electrophysiological properties compared to hiPSC-CM-Control. Furthermore, hiPSC-CM-FHCOE presented robust contrast and lower T2* values, signifying their potential as highly effective candidates for cardiac MRI. Next, hiPSC-CM-FHCOE is injected into mouse hearts and after 3 days of transplantation, MR images are obtained. hiPSC-CM-FHCOE cells exhibited clear signals in the hearts with lower T2* and rapid signal decay. Collectively, data from this proof-of-concept study demonstrated that endogenous labeling with FHC in hiPSC-CMs can be a potent strategy for enhancing the accuracy of cardiac MRI. This technology represents a significant step forward in tracking the transplanted hiPSC-CMs in the hearts of live animals.

Research Progress in Magnetic Resonance Imaging of Fetal Ventriculomegaly

Fetal ventriculomegaly is a central nervous system disorder commonly seen in prenatal imaging, and the prognosis ranges from normal health to severe dysfunction. Currently, fetal predictive markers associated with postpartum individual neurodevelopmental function are still not available, which increases the difficulty of prenatal diagnosis and clinical management. Constant advancements in magnetic resonance imaging (MRI) technology have brought better accuracy and reliability of MRI applied in the diagnosis, prognosis assessment, and etiology investigation of ventriculomegaly. MRI plays a critical role in prognostic management and prenatal consultation. Nevertheless, due to the potential safety hazards and economic and technical constraints of MRI, it is not the first choice for prenatal imaging diagnosis. Moreover, there are different opinions regarding the measurement results and grading criteria of ultrasound and MRI. At present, it is accepted that three-dimensional volume may provide reliable information for prognosis. However, accurate segmentation and measurement of brain structure remain serious challenges, and no consensus on the MRI measurement of lateral ventricle volume has been reached. In this paper, based on the latest research reports from China and around the world, we reviewed the progress in applying MRI in the prenatal diagnosis and treatment of ventriculomegaly. This review offers a theoretical foundation for further exploration of the role of lateral ventricle volume measurement in disease diagnosis and management. We suggest that researchers combine two-dimensional width with three-dimensional volume in the future to identify the optimal cutoff value for prognostic prediction of fetal ventriculomegaly.

Magnetic Resonance Imaging and 99Tc WBC-SPECT/CT Scanning in Differential Diagnosis between Osteomyelitis and Charcot Neuroarthropathy: A Case Series.

Distinguishing between Charcot Neuroarthropathy (CN), osteomyelitis (OM), and CN complicated with superimposed OM in diabetic patients is crucial for the treatment choice. Given that current diagnostic methods lack specificity, advanced techniques, e.g., magnetic resonance imaging (MRI) and 99mTc-HMPAO-WBC Single Photon Emission Computed Tomography (SPECT/CT), are needed. This study addresses the challenges in distinguishing OM and CN. We included diabetic patients with CN and soft tissue ulceration. MRI and 99mTc-HMPAO-WBC SPECT/CT were used for the diagnosis. The patients were classified into three probability levels for OM (i.e., Definite, Probable, and Unlikely) according to the Consensus Criteria for Diabetic Foot Osteomyelitis (CC-DFO). Eight patients met the eligibility criteria. MRI, supported by SPECT-CT and CC-DFO, showed consistency with the OM diagnosis in three cases. The key diagnostic features included the location of signal abnormalities and secondary features such as skin ulcers, sinus tracts, and abscesses. Notably, cases with inconclusive MRI were clarified by SPECT/CT, emphasizing its efficacy in challenging scenarios. The primary objective of this study was to compare the results of MRI and 99mTc-HMPAO-WBC SPECT/CT with the CC-DFO score in the diabetic foot with CN and suspected OM. Advanced imaging offers a complementary approach to distinguish between CN and OM. This can help delineate the limits of the disease for presurgical planning. While MRI is valuable, 99mTc-HMPAO-WBC SPECT/CT provides additional clarity, especially in challenging cases or when metallic implants affect MRI accuracy.

Accuracy of MRI Versus PET/CT in the Prediction of Treatment Response to Neoadjuvant Chemotherapy in Breast Cancer.

Background Breast-conserving surgeries have significantly advanced breast cancer treatment, offering favorable oncological outcomes, enhanced cosmetic results, reduced postoperative morbidity, and better psychological acceptance compared to mastectomy. The introduction of neoadjuvant therapy has expanded the applicability of breast conservation surgery to include locally advanced tumors. Tumor response to neoadjuvant chemotherapy is evaluated using imaging modalities such as breast ultrasound, breast magnetic resonance imaging (MRI), and positron emission tomography/computed tomography (PET/CT). Accurate prediction of therapeutic response facilitates the planning of surgical and adjuvant treatments. This study aims to compare the diagnostic accuracy of MRI and PET/CT in predicting treatment response to neoadjuvant chemotherapy in breast cancer patients. Methods This retrospective study was conducted at a tertiary care center in Bahrain. A total of 138 patients with locally advanced breast cancer or human epidermal growth factor receptor-2 (HER2) positive, hormone receptor-negative cancers who underwent breast-conserving surgeries between June 2018 and December 2022 were included. The inclusion criteria focused on patients achieving a complete pathological responsefollowing neoadjuvant systemic therapy, ensuring a homogenous study population. Patients with hormone receptor-positive early breast cancers or metastatic tumors, ineligible for neoadjuvant chemotherapy, were excluded. Non-responders and partial responders were also excluded from the study. Statistical analysis was performed using IBM SPSS v26.0 (IBM Corp., Armonk, US). Response rates for the imaging modalities and histopathology results were assessed. Agreement between histology and imaging modalities was computed using kappa statistics. Diagnostic performance for predicting "no residual" disease was evaluated using the McNemar Test. All tests were two-tailed, with a p-value <0.05 considered statistically significant. Results The study included 138 patients, of whom 73 (52.9%) had an incomplete response or residual disease, while 65 (47.1%) had a complete response or no residual disease according to histology reports. There was slight agreement between post-neoadjuvant MRI and histology results (Cohen's kappa 0.172, p=0.010), while substantial agreement was observed between post-neoadjuvant PET/CT and histology results (Cohen's kappa 0.614, p=0.000). PET/CT demonstrated a higher sensitivity of 93.8% (p<0.001) and a specificity of 68.5%. Although MRI was more specific, the positive predictive value was comparable for both PET/CT and MRI. Conclusion PET/CT shows higher sensitivity and can serve as an early marker for predicting complete pathological response in post-neoadjuvant breast cancer patients. However, the prediction of residual disease is optimized by combining both MRI and PET/CT as diagnostic modalities.

Diagnostic Accuracy of USG and MRI for the Detection of Rotator Cuff Injury.

Rotator cuff disease frequently causes shoulder pain and is diagnosed using various radiological methods alongside history and physical examination. Arthrography has traditionally been employed for this purpose, but newer non-invasive techniques such as ultrasonography (USG) and magnetic resonance imaging (MRI) are increasingly used. However, no single method is universally agreed upon as the best diagnostic tool, each having its own limitations. To evaluate how effectively ultrasound and MRIcan diagnose rotator cuff tears. Seventy patients suspected of having a rotator cuff tear underwent investigations at the Radiology Department of Krishna Vishwa Vidyapeeth (Deemed to be University), Karad. USG and MRI examinations were done on the same day, along with a detailed history. USG was conducted using a GE LOGIQ P9 machine with a high-frequency 3-12 MHz transducer. MRI was conducted using a 1.5T SiemensMagnetom Avanto scanner. Pain and stiffness are the most common complaints in rotator cuff tears. The predisposing factors include male predominance, increasing age, dominant hand use, and trauma history. The supraspinatus tendon is the most frequently injured, with partial tears, especially articular surface tears, being more common than full-thickness tears. Clinical examinations, USG, and MRI are valuable in diagnosing rotator cuff tears. Our findings indicate that USGmay not be as reliable in detecting rotator cuff tears as once believed. A positive ultrasound result is more trustworthy than a negative one. In contrast, MRIdemonstrates greater sensitivity and overall diagnostic accuracy compared to both ultrasonography and clinical assessment for detecting rotator cuff tears.

The Sensitivity and Specificity of Multiparametric Magnetic Resonance Imaging and Prostate-Specific Membrane Antigen Positron Emission Tomography/Computed Tomography for Predicting Seminal Vesicle Invasion in Clinically Significant Prostate Cancer: A Multicenter Retrospective Study.

Background/Objectives: The presence of seminal vesicle invasion (SVI) in prostate cancer (PCa) is associated with poorer postoperative outcomes. This study evaluates the predictive value of magnetic resonance imaging (MRI) and prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT) for SVI in PCa. Methods: This cohort study included consecutive robotic prostatectomy patients for PCa at three Australian tertiary referral centres between April 2016 and September 2022. MRI and PSMA PET/CT results, clinicopathological variables, including age, BMI, prostate-specific antigen (PSA), PSA density, DRE, Biopsy Gleason score, Positive biopsy cores, PIRADS v2.1 score, MRI volume and MRI lesion size were extracted. The sensitivity, specificity, and accuracy of MRI and PSMA PET/CT for predicting SVI were compared with the histopathological results by receiver operating characteristic (ROC) analysis. Subgroup univariate and multivariate analysis was performed. Results: Of the 528 patients identified, 86 had SVI on final pathology. MRI had a low sensitivity of 0.162 (95% CI: 0.088-0.261) and a high specificity of 0.963 (95% CI: 0.940-0.979). The PSMA PET/CT had a low sensitivity of 0.439 (95% CI: 0.294-0591) and a high specificity of 0.933 (95% CI: 0.849-0.969). When MRI and PSMA PET/CT were used in combination, the sensitivity and specificity improved to 0.514 (95%CI: 0.356-0.670) and 0.880 (95% CI: 0.813-0.931). The multivariate regression showed a higher biopsy Gleason score (p = 0.033), higher PSA (p < 0.001), older age (p = 0.001), and right base lesions (p = 0.003) to be predictors of SVI. Conclusions: MRI and PSMA PET/CT independently underpredicted SVI. The sensitivity and AUC improved when they were used in combination. Multiple clinicopathological factors were associated with SVI on multivariate regression and predictive models incorporating this information may improve oncological outcomes.

Role of MRI in classification and preoperative evaluation of perianal fistula

BackgroundA fistula is an unusual communication between the skin and an inward organ or between the organs. The current study aimed to determine the role of magnetic resonance imaging (MRI) in the diagnosis, description, and classification of fistula-in-ano. Additionally, the study aimed to compare the MRI findings with the operative findings, which is considered the gold standard in our study.MethodsThe present study is a prospective study and was carried out on a group of 61 patients: 52 males and 9 females with a mean age of 41 years, who were suspected to have perianal fistulae presented clinically with discharge or localized pain or were asymptomatic. A preoperative MRI was conducted for fistula-in-ano evaluation in these patients from October 2019 till the end of October 2021. A surgeon conducted a physical examination of all patients to document the number and location of cutaneous openings following a full medical history. The MRI images were evaluated and interpreted by multiple expert radiologists who had more than 5 years of experience in analyzing MRI. In the cases (in 3 cases, 4.92%) where there were discrepancies in their interpretations, a senior radiologist’s evaluation was considered the final result and was confirmed surgically. Subsequently, the MRI findings were correlated with surgical findings to indicate the specificity, sensitivity, and accuracy of such MRI findings.ResultsThe MRI technique was the routine (i.e., without contrast administration) technique in 36 (59.02%) patients, with contrast administration in 21 (34.43%) patients and with anesthesia/sedation (uncomfortable, anxious, and claustrophobic patients need to minimize their motion artifact to improve the quality and obtain more detailed images) in 4 (6.56%) patients. The MRI pathology of the studied patients revealed normal findings in 1 (1.64%) patient, anal fissure/early developing tract in 6 (9.84%) patients, and established tract (sinus/fistula) in 54 (88.52%) patients. Park’s and St. James's University Hospital classifications were utilized to categorize the patients, with the most common fistula types based on the Park’s classification: intersphincteric (44.3%) and transsphincteric (29.5%). Based on the St. James’s classification, grade 1 (intersphincteric (34.4%)) and grade 4 (transsphincteric with abscess/side branch (16.4%)) were the most prevalent. A substantial consensus was reached between MRI and surgery findings for classifying tracts, side branches, and abscesses formation with sensitivity, specificity, and accuracy of 100%, 85.71%, and 98.36%, respectively.ConclusionsMRI is a valuable tool in managing patients with perianal fistulas due to its ability to detect hidden areas of infection (such as abscesses) and secondary extensions. These factors contribute to the high recurrence rate after surgery. Additionally, MR imaging can define the anatomical relationships between the fistula and anal sphincters, helping to predict the likelihood of fecal incontinence following surgery.

Effectiveness of ultrasonography in the diagnosis of temporomandibular joint disorders: A systematic review and meta-analysis.

Temporomandibular disorders (TMDs) pose diagnostic challenges, and selecting appropriate imaging modalities is crucial for accurate assessment. This study aimed to compare the diagnostic accuracy and efficacy of ultrasonography (US) and magnetic resonance imaging (MRI) in identifying TMDs. A comprehensive meta-analysis was conducted, including studies that compared US and MRI for TMJ disorder assessments. Fixed-effects models were utilized to calculate pooled odds ratios (ORs) and relative risks (RRs) with 95% confidence intervals (CIs). Heterogeneity was assessed using the chi-squared test and I2 statistic. Newcastle-Ottawa scale was used to assess the methodological quality of the studies included. Six studies were included, involving a total of 281 participants. The meta-analysis demonstrated that MRI was statistically somewhat better than US in identifying TMJ disorders. The summary OR was 0.64 (95% CI: 0.46-0.90), and the summary RR was 0.80 (95% CI: 0.68-0.95). Heterogeneity among the studies was low (χ2 = 2.73, df = 5, p = .74; I2 = 0%). Demographic variables revealed variations in sample size, gender ratio and mean age across the studies. This meta-analysis provides evidence that MRI may be more effective than US in diagnosing TMDs. However, the study is limited by the small number of included studies and variations in demographic variables and study designs. Future research with larger samples and standardised protocols is essential to confirm and strengthen these findings. Understanding the diagnostic accuracy of MRI and US for TMJ disorders will aid clinicians in making informed decisions for effective TMJ disorder assessments and patient management.

Poster 271: Improving Non-Invasive Diagnosis and Grading of Cartilage Defects in the Knee - Accuracy of Ultra High Field 7-Tesla MRI as Compared with Arthroscopy

Objectives: Osteoarthritis (OA) is a joint disease characterized by degradation of articular cartilage and subchondral bone. Cartilage injury plays an important role in the pathogenesis of osteoarthritis, and disease modifying treatments aiming to preserve and possibly regenerate cartilage are an area of active interest. Early diagnosis is crucial, as the disease may be more responsive to treatment at an early stage, and there is a critical unmet need for improved non-invasive morphologic cartilage imaging techniques. Standard clinical MRI is performed on a 1.5T or 3T machine. Ultra-high field (UHF) 7-Tesla (7T) magnetic resonance imaging (MRI) is a new technology that offers 2.3x improved signal-to noise ratio (SNR) compared to 3T MRI and 2.8x SNR compared to 1.5T MRI. The purpose of this study was to estimate the accuracy of 7T MRI for the detection and grading of cartilage lesions in the knee. The hypothesis was that 7T images would offer better detection and more accurate grading of chondral lesions than standard clinical grade MRI scans. Methods: In this prospective, paired, blinded study, patients who had undergone a 1.5 or 3T standard of care (SOC) MRI and were scheduled for knee arthroscopy were enrolled (10/2019 to 08/2021) and a study intervention 7T MRI was performed prior to surgery. The study was approved by our institutional review board, and it was funded by the Methodist-Siemens Collaboration. Exclusion criteria included contraindication to MRI (e.g., pacemaker), weight less than 30 kg, and pregnancy. Scans were reviewed by three independent fellowship-trained radiologists who were blinded to clinical and arthroscopic data. Scans were reviewed over 5 days, with a 4 week “washout” period between review of SOC and 7T scans to limit recall bias. Readers were blinded to clinical and arthroscopic data and graded all six articular surfaces of the knee (patella, trochlea, lateral condyle, medial condyle, lateral tibia, medial tibia) using a modified Outerbridge classification system. At the time of arthroscopy, each articular surface was graded by the operating surgeon according to a modified Outerbridge system similar to above, with the exception that Grade 1 = softening of the articular cartilage. The surgeon was blinded to 7T images at the time of arthroscopy, although they had access to the SOC MRI, which was necessary for patient care. Using arthroscopy as the gold standard, we calculated sensitivity and specificity of SOC MRI and 7T MRI. An Outerbridge grade of 0 was classified as negative, while a grade of 1-4 was classified as positive. A secondary analysis of sensitivity and specificity was performed on a per articular surface basis, with 6 articular surfaces per patient after correction for within subject clustered data. A Mann-Whitney U test was used to compare diagnostic scores and ratings between instruments (SOC vs. 7T). Coefficients of variation between observers within each instrument were compared for each variable using a paired sample t-test. Type-I error was set at alpha=0.05 Results: A total of 100 patients (age: 43 ± 14, 54 female, 46 male) were enrolled. 7T MRI resulted in improved sharpness (defined by visibility of nerve fascicles) and shading (based on artifacts) compared to SOC MRI (Figure 1, p &lt; 0.001 for both). There was improved contrast between fluid and cartilage with 7T MRI (using confidence rating at axial mid-patella, p = 0.003). 7T MRI had a higher sensitivity in detecting cartilage lesions for five of the six articular surfaces when using the arthroscopic gold standard, but with lower specificity for all surfaces (Figure 2). Finally, there was improved inter-observer reliability in detecting and grading cartilage defects with 7T compared to SOC MRI (p &lt; 0.05). Conclusion: Based on our findings thus far, 7T MRI appears to result in improved measurement ratings, sensitivity, and inter-observer reliability compared to SOC in detecting cartilage lesions in the knee. Further work is needed to evaluate cost effectiveness of 7T MRI.

Poster 105: MRI Demonstrates Similar Diagnostic Value to MR Arthrogram for Determining Labral Tear Extent up to 2 Weeks Following Shoulder Dislocation

Objectives: The aim of this study was to determine the comparative accuracy and precision of routine Magnetic Resonance Imaging (MRI) versus magnetic resonance (MR) arthrogram in measuring labral tear size as function of time from shoulder dislocation, and to identify a time threshold after which MR arthrogram supersedes MRI in diagnostic utility. Methods: We retrospectively evaluated consecutive patients who underwent primary arthroscopic labral repair between 2012 and 2021 and completed a preoperative MRI or MR arthrogram of the shoulder within 60 days of injury, and subsequently underwent arthroscopic repair within 6 months of imaging. Arthroscopic labral tear size and location was used as standard comparison. Three musculoskeletal radiologists independently interpreted tear extent using clock-face convention. Accuracy and precision of MR labral tear measurements were defined by location and size of the tear, respectively. Accuracy and precision were compared between MRI and MR arthrogram, as a function of time from dislocation. Results: Thirty-two MRI and 65 MR arthrogram (total n=97) were independently assessed by radiologists. Multivariate analysis demonstrated that intraoperative tear size, early imaging, and arthrogram status were associated with increased MR accuracy and precision (p&lt;0.05). Ordering surgeons preferred arthrogram for delayed imaging (p=0.018). For routine MRI, error in accuracy increased by 3.4° per day and error in precision increased by 2.3° per day (p&lt;0.001) from time of injury. MR arthrogram, however, was not temporally influenced (Figure 1). Significant loss of accuracy and precision of routine MRI compared to MR arthrogram occurs at 2 weeks after acute shoulder dislocation. Conclusions: For determining shoulder labral tear size after acute dislocation, routine MRI has similar diagnostic value for measuring labral tear extent as MR arthrogram up to approximately 2 weeks postacute shoulder dislocation, after which it significantly loses accuracy and precision, possibly due to resolving posttraumatic effusion. MR arthrogram accuracy and precision were not temporally influenced.

Paper 41: Does MR Arthrography Improve Evaluation of Patients with Posterior Shoulder Instability? An Analysis from the MOON Shoulder Instability Group

Objectives: Posterior shoulder instability is an uncommon injury, accounting for 2-12% of shoulder instability patients. Magnetic resonance imaging (MRI) is often utilized to non-invasively evaluate the joint for labral, cartilage, and bony injury. MR arthrography (MRA) may improve the evaluation of these intra-articular structures, but requires additional cost, time, and an invasive procedure. Moreover, its benefits for patients with posterior shoulder instability are unclear. Accurate imaging is critical in patients undergoing surgery because certain findings may influence the surgical approach. Thus, the purpose of this study is to compare the accuracy of MRA and non-enhanced MRI in detecting labral, chondral, and osseous lesions in patients with posterior shoulder instability. Methods: There were 291 patients with unilateral posterior shoulder instability who had preoperative MRA or MRI between 2006 and 2021 in the MOON database. Images were reviewed by a fellowship-trained musculoskeletal radiologist with 10+ years of experience and an orthopaedic surgeon. Evaluators were blinded to age, gender, medical history, MR report, and arthroscopic findings, but were aware of the patient's history of posterior shoulder instability. Examinations were evaluated for presence, location, morphology, and length of glenoid labral tears. Tear length and localization were noted using a standard clock face. The presence and size of humeral/glenoid osseous and cartilage lesions was also noted.Intraoperative findings from arthroscopic evaluation were documented by the surgeon using a standard response questionnaire. Diagnostic performance of standard MRA and MRI were evaluated using sensitivity and specificity with arthroscopic evaluation as the gold-standard. Chi-squared or Fisher’s exact tests were used to compare the sensitivities and specificities of MRA and MRI. Significance was defined as P &lt; 0.05. Results: 200 patients (69%) had MRA, while 91 patients had non-contrast MRIs of the shoulder. On imaging evaluation, 273 (94%) patients had labral tears with a mean tear size of 156º. 39 (13%) patients had humeral cartilage lesions, whereas 40 (14%) patients had glenoid cartilage lesions. 34 (12%) patients had glenoid bone loss greater than 5%. The mean glenoid bone loss was 12% (range, 5% - 26%). A reverse Hill-Sachs lesion was present in 35 (12%) patients. 16 (6%) patients had bipolar bone loss. The sensitivity for detection of labral tears was high for both MRA (0.95) and standard MRI (0.98) (Tables 1 and 2), though the specificity was low for both modalities (0.25 and 0.40, respectively). There was no difference in the sensitivities or specificities of the two imaging modalities in the detection of labral tears. MRA had a lower sensitivity than MRI in the detection of glenoid cartilage lesions (0.31 vs 0.88, p &lt; 0.001), but no difference was observed for specificity. There was no difference in the sensitivities and specificities of MRA and MRI for humeral cartilage lesions (p = 0.354).MRA had a higher sensitivity than MRI in assessing glenoid bone loss (0.78 vs 0.50, p &lt; 0.001), though there was no difference in specificity. There was no difference between imaging modalities in the evaluation of humeral bone loss (p = 1.000). Conclusions: In this multicenter study, MRA was the most commonly utilized preoperative advanced imaging study for patients with posterior shoulder instability. MRA had a higher sensitivity in detecting glenoid bone loss but lower sensitivity in detecting glenoid cartilage lesions compared to standard non-contrast MRI. There was no difference in diagnostic performance between MRA and MRI in the diagnosis of labral tears and humeral chondral and osseous lesions. MRA may provide an advantage over standard MRI in the evaluation of glenoid bone loss, which can influence the treatment plan for patients undergoing surgical management of posterior shoulder instability.

A prospective observational study on magnetic resonance imaging (MRI) based evaluation of pelvic masses in females in tertiary care hospital in central India

Background Pelvic masses in females often present a diagnostic challenge, necessitating accurate detection and characterization for appropriate clinical management. Magnetic Resonance Imaging (MRI) has emerged as a valuable tool in pelvic mass evaluation, offering superior soft tissue contrast and multiplanar imaging capabilities. This prospective observational study aims to assess the diagnostic accuracy of pelvic MRI, determine anatomic origin, classify masses, estimate local spread, and evaluate the impact of gadolinium contrast in a tertiary care hospital in Central India. Methods The study will be conducted over a two-year period, enrolling female patients with lower back pain and clinical suspicion or inconclusive ultrasonographic findings of pelvic masses. A systematic approach to participant identification, recruitment, and engagement will be employed, with both verbal and written informed consent obtained. The imaging protocol will involve T1 and T2 weighted images, and gadolinium contrast administration when necessary. Data collection will encompass demographic information, medical history, clinical details, and MRI findings. Statistical analyses, including sensitivity, specificity, prevalence estimates, and regression analyses, will be performed to evaluate the diagnostic accuracy of pelvic MRI. Expected outcome We anticipate that pelvic MRI will exhibit high diagnostic accuracy in detecting and characterizing pelvic masses, providing valuable information on anatomic origin and pelvic compartment localization. The study aims to contribute evidence on the impact of gadolinium contrast in enhancing diagnostic capabilities. The findings are expected to optimize clinical decision-making for effective management of females with pelvic masses, leading to timely interventions and improved patient outcomes.

Ultrasound versus MRI for evaluation of silicone leakage from silicone breast implants

BackgroundImplant ruptures and gel bleed are not uncommon among women with silicone breast implants. While magnetic resonance imaging (MRI) is traditionally considered the gold standard diagnostic modality, recent studies suggest ultrasound might be an acceptable alternative. This study compares the efficacy of ultrasound and MRI in assessing implant integrity. MethodsWomen with silicone breast implants underwent a breast and axillary ultrasound and MRI on the same day. All tests were assessed by experienced radiologists. The accuracy, sensitivity, and specificity of ultrasound and MRI for implant rupture detection and silicone depositions in axillary lymph nodes were evaluated. FindingsA total of 104 women participated in the study. The accuracy, sensitivity, and specificity of ultrasound for detecting implant ruptures compared to MRI were 96 %, 95 %, and 96 %, respectively. MRI demonstrated significantly lower sensitivity (44 %) for detecting silicone depositions in axillary lymph nodes compared to ultrasound. A significant association was observed between the presence of enlarged axillary lymph nodes and/or axillary pain and the detection of silicone depositions in axillary lymph nodes on ultrasound (χ2 (1, N = 104) = 5·1, p = 0·024). Six women exhibited silicone depositions in axillary lymph nodes despite having intact first-pair implants, indicative of gel bleed. InterpretationUltrasound is nearly as effective as MRI for detecting breast implant ruptures and is superior for detecting silicone depositions in axillary lymph nodes. We therefore recommend initiating radiological examination in women with breast implants with a breast and axillary ultrasound, proceeding to MRI only if the ultrasound is inconclusive. The prevalence of gel bleed is understudied and its potential adverse health effects might be underestimated. Further research is needed to explore its potential association with development of systemic symptoms.