Magnetic Resonance Imaging Group Research Articles

Survival in dogs with meningoencephalomyelitis of unknown etiology with and without lesions detected by magnetic resonance imaging.

The prognosis of individual dogs with meningoencephalomyelitis of unknown etiology (MUE) remains difficult to predict. MUE cases with no lesions detected by magnetic resonance imaging (MRI) occur, but it is unknown whether this finding is associated with prognosis. MUE cases without detectable lesions on MRI have a better outcome than cases with detectable lesions. Study included 73 client-owned dogs with MUE presenting to Purdue University Veterinary Hospital from 2010 to 2020. Retrospective study. Dogs with a clinical diagnosis of MUE were identified by medical record search. MRI reports were reviewed for presence or absence of lesions consistent with MUE. Clinical findings at presentation, treatment, disease-specific survival, and outcomes including rates of remission and relapse were compared between cases with normal MRI or abnormal MRI. Overall, 54 dogs (74%) were classified as abnormal MRI, and 19 dogs (26%) were classified as normal MRI cases. Death caused by MUE occurred in 1/19 (5%) normal MRI dogs and 18/54 (33%) abnormal MRI dogs (P = .016). Median survival was >107 months in both groups, but survival was significantly longer in the normal MRI group (P = .019). On multivariate analysis, abnormal MRI was significantly related to death (hazard ratio, 7.71; 95% confidence interval 1.03-58.00, P = .0470), whereas significant relationships with death were not identified for either the use of secondary immunosuppressive medications or cerebrospinal fluid nucleated cell count. MUE dogs with no detectable lesions on MRI have reduced disease-related death compared with dogs with abnormal MRI. The presence or absence of MRI lesions in MUE dogs is prognostically relevant.

Pediatric Cervical Spine Clearance after Blunt Trauma and Negative CT: What is the Role of MRI?

Background and purposeThe cervical spine in children has marked anatomical and biomechanical differences compared to adults, leading to significantly different patterns and incidence of spinal injury, and consequently to different X-Ray and computed tomography (CT) imaging recommendations. Magnetic resonance imaging (MRI) has been validated to clear cervical spine trauma in adults, but not in pediatric patients. We hypothesized that MRI findings have a low probability to change management in children with spine trauma and negative CT findings. Materials and methodsWe reviewed records for admitted pediatric patients due to blunt trauma from January 2011 to May 2021, and identified 212 patients who underwent MRI within 3 days of a negative CT. Two neuroradiologists independently reviewed all CT and MRI images for the following categories: fracture, subluxation, spinal canal compromise, ligamentous injury, spinal canal hemorrhage, cord contusion and soft tissue hemorrhage. We identified follow-up MRI examinations as negative or positive for the above categories, and calculated the prevalence of each category as a percentage of cases with negative CT. We also evaluated whether negative and positive MRI groups differed significantly with respect to age and sex of the patients. Results and conclusionsIn our study of 212 children with cervical spine trauma and a negative CT, most follow-up MRI scans were found to be negative (79.9%). Positive MRI findings consisted mainly of ligamentous sprain without disruption (15.1%). Ligamentous disruption and epidural or soft tissue hemorrhage were found in 4.5%, and focal cord contusion in 0.5%. There was no statically significant difference between negative and positive MRI groups with respect to age (P = 0.45) and sex (P = 0.52). ConclusionIn our patient group with a negative CT, MRI did not significantly impact management nor contribute to cervical spine clearance in children.

Comparison the Perfusion/Diffusion Mismatching Judging From CT-Based and MR-Based Study

Background: The development of endovascular devices and clinical experience, recanalization rate after intraarterial thrombectomy (IA-Tx) has increased. Recent papers reported that the amount of perfusion/diffusion (P/D)-mismatching in digital analysis from computer tomography perfusion (CTP) image is well correlated well with P/D-mismatching from magnetic resonance image. The purpose of this study is compare the patient clinical outcomes after IA-Tx, judging from CTP based and magnetic resonance imaging (MRI) based study. Methods : 218 patients with anterior circulation large vessel occlusion (LVO) treated by IA-Tx were included in this analysis. In the MRI group (n=80), P/D-mismatching from MRI based image analysis by visual method and in the CTP group (n=138), and recently, P/D-mismatching was decided by automatized computer programmatic analyzed from CTP based image (Syngo.via program). Results: Favorable outcome (modified Rankin Score: 0–2), mortality, recanalization, and clinically significant hemorrhage was 56.3% (45/80), 6.25% (5/80), 81.3% (65/80) and 25% (20/80) in MRI group and 4.9% (62/138), 8.9%(18/138), 91.3%(126/138) and 40.6% (56/138) in CTP group (p=0.000, 0.235, 0.007 and 0.013). Reperfusion injury (27.5% vs, 15.0%, p=0.018) but favorable outcome was high 55.0% vs. 44.9 $, p=0.00) in the MRI study group. Conclusion : In our study, patient selection according to the P/D-mismatching from MR-based imaging and CTP-based image was not different in final clinical outcome. Recent IA-Tx, showed high recanalization rate but it also cause high incidence of reperfusion injury.

Advanced MRI metrics improve the prediction of baseline disease severity for individuals with degenerative cervical myelopathy

BACKGROUND CONTEXTDegenerative cervical myelopathy (DCM) is the most common form of atraumatic spinal cord injury globally. Degeneration of spinal discs, bony osteophyte growth and ligament pathology results in physical compression of the spinal cord contributing to damage of white matter tracts and grey matter cellular populations. This results in an insidious neurological and functional decline in patients which can lead to paralysis. Magnetic resonance imaging (MRI) confirms the diagnosis of DCM and is a prerequisite to surgical intervention, the only known treatment for this disorder. Unfortunately, there is a weak correlation between features of current commonly acquired MRI scans (“community MRI, cMRI”) and the degree of disability experienced by a patient. PURPOSEThis study examines the predictive ability of current MRI sequences relative to “advanced MRI” (aMRI) metrics designed to detect evidence of spinal cord injury secondary to degenerative myelopathy. We hypothesize that the utilization of higher fidelity aMRI scans will increase the effectiveness of machine learning models predicting DCM severity and may ultimately lead to a more efficient protocol for identifying patients in need of surgical intervention. STUDY DESIGN/SETTINGSingle institution analysis of imaging registry of patients with DCM. PATIENT SAMPLEA total of 296 patients in the cMRI group and 228 patients in the aMRI group. OUTCOME MEASURESPhysiologic measures: accuracy of machine learning algorithms to detect severity of DCM assessed clinically based on the modified Japanese Orthopedic Association (mJOA) scale. METHODSPatients enrolled in the Canadian Spine Outcomes Research Network registry with DCM were screened and 296 cervical spine MRIs acquired in cMRI were compared with 228 aMRI acquisitions. aMRI acquisitions consisted of diffusion tensor imaging, magnetization transfer, T2-weighted, and T2*-weighted images. The cMRI group consisted of only T2-weighted MRI scans. Various machine learning models were applied to both MRI groups to assess accuracy of prediction of baseline disease severity assessed clinically using the mJOA scale for cervical myelopathy. RESULTSThrough the utilization of Random Forest Classifiers, disease severity was predicted with 41.8% accuracy in cMRI scans and 73.3% in the aMRI scans. Across different predictive model variations tested, the aMRI scans consistently produced higher prediction accuracies compared to the cMRI counterparts. CONCLUSIONSaMRI metrics perform better in machine learning models at predicting disease severity of patients with DCM. Continued work is needed to refine these models and address DCM severity class imbalance concerns, ultimately improving model confidence for clinical implementation.

Cardiovascular Imaging-Derived Skeletal Muscle Mass Correlates With Fitness and Survival in Patients With Univentricular Circulation.

Aims This study aims to retrospectively quantify skeletal muscle mass from cardiovascular imaging studies in total cavopulmonary connection (TCPC) patients and to correlate calculated muscle mass with clinical outcomes. Materials and methods Ninety-one TCPC patients at a mean age of 24.0 ±5.5 years (37 women; 40.7%) who underwent chest computed tomography (CT) or cardiac magnetic resonance imaging (MRI) as part of their follow-up were identified in a single-center database. The cross-sectional skeletal muscle index (SMI) at the Th4 and Th12 levels was calculated from CT images, and the dorsal skeletal muscle area (SMA) at the Th12 level was measured from an MRI. Results Calculated SMI at Th12 level was 38.0 (34.5; 42.0) cm2.m-2 or 89.6 (81.9; 101.6) % of predicted values. The median follow-up from CT was 5.9 (3.1; 8.5) years, and the composite endpoint (death N=5, heart transplant N=6) was reached in a total of 11 (26.8%) patients. Patients with SMI (Th12) less than 90% of predicted values had a hazard ratio of 5.8 (95% CI: 1.2; 28.3) (p=0.03) for endpoint achievement. In the MRI group, dorsal SMA at the Th12 level was 27.6 ±5.1 cm2 in men and 20.0 ±5.8 cm2 in women. Correlations were found between SMA/kg and peak oxygen uptake (VO2peak) (r=0.48, p=0.0005) and fat-free mass (r=0.63, p<0.0001), respectively. Conclusions A low SMI at the Th12 level was associated with a higher risk of death or cardiac transplantation. Evaluation of skeletal muscle mass using cardiovascular imaging methods allows rapid identification of individuals at risk of sarcopenia.

Abstract WP119: Magnetic Resonance Imaging versus Computed Tomography Before Mechanical Thrombectomy for Acute Ischemic Stroke

Introduction: Magnetic resonance imaging (MRI) and computed tomography (CT) is useful for the evaluation of the ischemic core and penumbra. The indication for mechanical thrombectomy (MT) for acute ischemic stroke is determined by either or both imaging modalities. The selection of initial imaging modality is differed by the institute, and it is uncertain which imaging modality is superior before MT. In this study, we compared the clinical outcomes after MT by imaging modality in the K-NET registry (Kanagawa intravenous and endovascular treatment of acute ischemic stroke registry). Methods: The K-NET registry is a Japanese multicenter prospective registry study of patients treated with Intravenous thrombolysis with recombinant tissue plasminogen activator, endovascular treatment, or both for acute ischemic stroke. The present study is based on patients' data in the K-NET registry between January 2018 and June 2021. The inclusion criteria for the current analysis were as follows: (1) pre-modified Rankin score (mRS) 0-2; (2) patients transferred directly to primary stroke centers; (3) treated with MT; and (4) performed only CT or MRI for diagnosis of acute ischemic stroke before MT. The patients who performed both CT and MRI at admission were excluded. Unbalanced cohorts with a nonrandom distribution of patients were accounted for by using propensity score matching. Results: 2348 patients were enrolled in the registry during the period, and 753 patients were eligible for inclusion criteria. 498 (249 matched pairs) were included after propensity score-matched analysis. The baseline characteristics were well-balanced between the two groups. There was no difference in the final mTICI grade between the two groups. The time from image to puncture in the MRI group was significantly shorter than the CT group (52min versus 38min), and the time from image to recanalization was also significantly shorter in the MRI group (108min versus 88.5min). The rate of functional independence (90 days mRS 0-2) was higher in the MRI group versus the CT group (54.4% versus 43.8%, p=0.017). Conclusions: The selection of MRI before MT was associated with a shorter time from image to puncture and recanalization and a favorable outcome compared with CT.

Effect of 14.1T MRI on Mercury Amalgam: A Study by ICP-MS and XRD

Aim: The aim of this study was to evaluate the effect of electromagnetic effects of magnetic resonance imaging (MRI) on the release of mercury (Hg) and on the possible amalgam phase change in amalgam with 14.1T MRI. Material and methods: 60 amalgam discs with 4 mm diameter and 4 mm height were prepared. 30 were selected as the control and 30 as MRI group. They were placed in the Fusayama-Meyer solution. MRI group were exposed to 14.1T ultra-high-field magnetic resonance imaging (UHF-MRI) system (EPFL, Lausanne, Switzerland). 2, 12 and 24 hours after MRI, all discs were removed from the solutions. Inductively coupled plasma-mass spectroscopy (ICP-MS) analysis was performed to the solutions. X-ray diffractometry (XRD) was performed to amalgam discs. Differences and interactions between groups were evaluated by two-way ANOVA. Results: The concentration of Hg released from the amalgams to the solution in the MRI group was significantly higher than the control group (p=0,026; F=5,253). The peak intensity of the amalgam in the MRI group obtained by XRD was significantly lower than the control group (p = 0.000). Conclusion: UHF-MRI increases the release of Hg in the amalgam due to the strength of the magnetic field and appears to have a debilitating effect on the crystal structure of the amalgam within the period of exposure to the magnetic field.

Can rectal MRI and endorectal ultrasound accurately predict the complete response to neoadjuvant immunotherapy for rectal cancer?

Standardized assessments of clinical complete response (cCR) to neoadjuvant chemoradiotherapy (nCRT) for rectal cancer have been established, but their utility and accuracy remain unclear. This study aimed to evaluate the clinical diagnostic value of rectal magnetic resonance imaging (MRI) and endorectal ultrasonography (ERUS) for the determination of cCRs after neoadjuvant immunotherapy and to investigate the concordance between cCR and pathological complete response (pCR). Ninety-four patients with rectal cancer treated with neoadjuvant radiotherapy with or without immunotherapy were included. The sensitivity, specificity, and accuracy of each evaluation method were calculated. Combined MRI and ERUS assessments found cCR in seven of the 94 patients in our cohort. In the non-immunotherapy group, the sensitivity, specificity, and accuracy of MRI for diagnosing cCR were 50.0%, 85.2%, and 77.1%, respectively, whereas those of ERUS were 50.0%, 92.6%, and 82.9%, respectively; those of combined MRI and ERUS were 25.0%, 96.3%, and 87.5%, respectively. In the immunotherapy group, the sensitivity, specificity, and accuracy with which MRI identified CR were 51.7%, 76.7%, and 64.4%, respectively; those of ERUS were 13.8%, 90.0%, and 52.5%, respectively, and those of combined MRI and ERUS were 10.3%, 96.7%, and 54.2%, respectively. We also found that 32 of 37 patients with pCR did not meet the cCR evaluation criteria. Of these pCR patients, 78.4% (29/37) received immunotherapy. In the entire cohort, there were five pCRs among the seven cCRs. Of the four cCRs that occurred in the immunotherapy group, three were pCRs. Rectal MRI and/or ERUS did not provide sufficiently accurate assessments of cCR in patients with rectal cancer receiving neoadjuvant therapy, especially immunotherapy, and cCR did not predict pCR.

Brain magnetic resonance imaging as predictors in pediatric anti-N-methyl-D-aspartate receptor encephalitis

ObjectiveTo investigate the associations between brain magnetic resonance imaging (MRI) changes and clinical profiles in children with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. MethodsClinical data and brain MRI results of children diagnosed with anti-NMDAR encephalitis in Guangzhou Women and Children's Medical Center from October 2014 to June 2022 were retrospectively studied. ResultsA total of 143 children (Male: female 54:89) were enrolled, with a mean onset age of 6.8 years (6.8 ± 3.1). 40.6 % (58/143) of patients had abnormal initial brain MRI. Lesions in temporal lobe (34.5 %, 20/58) and frontal lobe (25.9 %, 15/58) were relatively common. Children with abnormal initial brain MRI were prone to have fever (P = 0.023), dystonia (P = 0.037), positive MOG antibodies (P = 0.015), higher cerebrospinal fluid (CSF) white blood cell count (WBC) (P = 0.019) and to receive rituximab treatment (P = 0.037). There were no significant differences in modified Rankin Scale (mRS) scores before immunotherapy, after immunotherapy and at last follow-up between the normal initial brain MRI group and abnormal group. No initial brain MRI changes were found to be associated with relapses. Brain MRI was reviewed in 72 patients at last follow-up with a median follow-up time of 25.5 months and 48.6 % (35/72) of patients had abnormal brain MRI. The mRS score of the group with normal brain MRI at last follow-up was significantly lower than that of the abnormal group. ConclusionsAbout 40.0 % of children with anti-NMDAR encephalitis had abnormal initial brain MRI. Initial brain MRI was associated with certain clinical profiles, but not with relapse and prognosis. Around half of patients had abnormal brain MRI at last follow-up and were prone to have higher mRS score.

Volumetric changes in brain MRI of infants with hypoxic-ischemic encephalopathy and abnormal neurodevelopment who underwent therapeutic hypothermia

BackgroundHypoxic-ischemic encephalopathy (HIE) is a severe neonatal complication that can result in 40–60 % of long-term morbidity. Magnetic Resonance Imaging (MRI) is a noninvasive method which is usually performed before discharge to visually assess acquired cerebral lesions associated with HIE and severity of lesions possibly providing a guide for detecting adverse outcomes. This study aims to evaluate the impact of HIE on brain volume changes observed in MRI scans performed at a mean 10 days of life, which can serve as a prognostic indicator for abnormal neurodevelopmental (ND) outcomes at 18–24 months among HIE infants. MethodsWe retrospectively identified a cohort of HIE patients between June 2013 and March 2017. The inclusion criteria for therapeutic hypothermia (TH) were a gestational age ≥35 weeks, a birth weight ≥1800 g, and the presence of ≥ moderate HIE. Brain MRI was performed at a mean 10 days of life and brain volumes (total brain volume, cerebral volume, cerebellar volume, brain stem volume, and ventricle volume) were measured for quantitative assessment. At 18–24 months, the infants returned for follow-up evaluations, during which their cognitive, language, and motor skills were assessed using the Bayley Scales of Infant and Toddler Development III. ResultsThe study recruited a total of 240 infants between 2013 and 2017 for volumetric brain MRI evaluation. Among these, 83 were normal control infants, 107 were TH-treated HIE infants and 37 were HIE infants who did not receive TH due to contraindications. Clinical evaluation was further proceeded. We compared the brain volumes between the normal control infants (n = 83) with normal ND but TH-treated HIE infants (n = 76), abnormal ND TH-treated HIE infants (n = 31), and the severe HIE MRI group with no TH (n = 37). The abnormal ND TH-treated HIE infants demonstrated a significant decrease in brainstem volume and an increase in ventricle size (p < 0.001) (Table 4). Lastly, the severe brain MRI group who did not receive TH showed significantly smaller brain stem (p = 0.006), cerebellar (p = 0.006) and cerebrum volumes (p = 0.027), accompanied by larger ventricular size (p = 0.013) compared to the normal control group (Table 5). ConclusionIn addition to assessing the location of brain injuries in MRI scans, the reduction in brain stem volume coupled with an increase in ventricular volume in HIE infants may serve as a biomarker indicating severe HIE and adverse long-term ND outcomes among HIE infants who either received therapeutic hypothermia (TH) treatment or not.

Magnetic Resonance Imaging–Targeted Versus Systematic Prostate Biopsies: 2-year Follow-up of a Prospective Randomized Trial (PRECISE)

BackgroundThe prospective randomized PRECISE trial demonstrated that magnetic resonance imaging (MRI) with only targeted biopsy (TBx) was noninferior to systematic transrectal ultrasound biopsy (SBx) in the detection of International Society of Urological Pathology grade group (GG) ≥2 prostate cancer (PC). An unanswered question is the outcome for patients who avoided a biopsy because of negative MRI findings. ObjectiveTo explore the rate of PC diagnosis based on 2-yr MRI for PRECISE participants who had no biopsy and for patients who had a negative result or GG 1 on TBx in comparison to those with a negative result or GG 1 on SBx. Design, setting, and participantsThe PRECISE prospective trial was conducted at five Canadian academic centers. The present analysis was for trial participants who were not diagnosed with clinically significant PC (csPC) at baseline. Of 453 randomized patients, 146 were diagnosed with GG ≥2 at baseline and were excluded. Eligible patients for this study included 83 men from the MRI arm who had negative MRI findings and no biopsy, 120 from the overall cohort who had a negative SBx or TBx, and 72 from the overall cohort who were diagnosed with GG 1 disease. InterventionMRI at 2 yr in all men in the MRI and SBx arms and TBx for lesions with a Prostate Imaging-Reporting and Data System score of ≥3 or on the basis of clinical suspicion. Outcome measurements and statistical analysisThe primary outcome was the proportion of men diagnosed with GG ≥2 cancer. Secondary outcomes included the MRI outcome and the proportion of men diagnosed with GG 1 PC. Results and limitationsEvaluable 2-yr MRI scans were available for 75 (56%) eligible patients in the MRI arm and 69 (49%) in the SBx arm. Of these patients, 55 (73%) in the MRI arm and 51 (67%) SBx arm had negative 2-yr MRI. Of the 76 patients in the SBx arm with 2-yr MRI, 16 (21%) had a biopsy, for which the result was negative in eight (10%), GG1 in two (2.6%), and GG ≥2 in six (7.9%) cases. Of the 75 men in the MRI arm with 2-yr MRI, eight (11%) were biopsied, for which the result was negative in four cases (5%) and GG ≥2 in the other four (5%). At 2 yr, including baseline biopsy results, 116/221 (52.5%) in the MRI arm and 113/204 (55%) in the SBx arm were free of GG ≥2 disease, treatment, death from any cause, or progression (OR 1.08; p = 0.66). ConclusionsAfter 2-yr follow-up including MRI for patients in both arms of PRECISE, there was no difference in the rate of csPC diagnosis between the MRI and SBx groups, even though 38% of men in the MRI group avoided an initial biopsy. Patient summaryThe PRECISE trial compared systematic biopsy of the prostate to a strategy of magnetic resonance imaging (MRI) with targeted biopsy of any lesions suspicious for cancer on the scan. After 2 years of follow-up that included 2-year MRI with or without biopsy in both groups, there was no difference in the rate of diagnosis of significant cancer, even though 38% of men in the initial MRI arm avoided an initial biopsy, and 30% avoided biopsy altogether.The PRECISE trial is registered on ClinicalTrials.gov as NCT02936258.

Gastrointestinal tumor-related perihepatic fluorouracil encapsulated lesions and liver metastases: a diagnostic imaging study based on contrast-enhanced computed tomography and magnetic resonance imaging.

Perihepatic fluorouracil encapsulated lesions (FELs) can result in potentially confusing computed tomography (CT) and magnetic resonance imaging (MRI) features in postoperative examinations of gastrointestinal tumors. This retrospective study aimed to summarize the typical imaging features of FELs and determine the best imaging modality to distinguish FELs from liver metastases for junior residents. Patients with FELs who had undergone gastrointestinal tumor surgery in Tongji Hospital from January 2016 to June 2022 were evaluated. The imaging features of FELs were summarized by two senior radiologists. Contrast-enhanced CT (CECT) was used as the primary follow-up tool for postoperative gastrointestinal tumor patients. Patients with FELs and available CECT and MRI examinations were matched with patients with liver metastases based on gender and age and presented in chronological order in a 2:1 ratio. Different imaging modality combinations were used for further evaluation, including a CECT group (modality Ⅰ), CECT and nonenhanced MRI group (modality Ⅱ) and CECT with all MRI sequences group (modality Ⅲ). Subsequently, two junior residents blindly evaluated three groups following a 4-week interval based on a 5-point scale (1= definite benign lesion, 2= probable benign lesion, 3= indeterminate, 4= probable liver metastasis, 5= definite liver metastasis). Imaging features of 33 patients with 36 FELs were analyzed. CECT and dynamic contrast-enhanced MRI (DCE-MRI) showed no enhancement in most lesions. Additionally, 20 patients with FELs meeting the requirements were matched with 40 patients with liver metastases. The highest sensitivity, specificity, and consistency for identifying liver metastases were achieved using a combination of CECT and MRI encompassing all sequences yielded, including modality Ⅰ (reader 1: 72.0% and 17.4%; reader 2: 62.0% and 17.4%; kappa value 0.295), modality Ⅱ (reader 1: 88.0% and 8.7%; reader 2: 92.0% and 34.8%; kappa value 0.259), and modality Ⅲ (reader 1: 98.0% and 34.8%; reader 2: 92.0% and 39.1%; kappa value 0.680). FELs are typically non-enhancing lesions. In our study, two junior residents could best distinguish FELs from liver metastases using CECT with all MRI sequences.

Supplemental magnetic resonance imaging plus mammography compared with magnetic resonance imaging or mammography by extent of breast density.

Examining screening outcomes by breast density for breast magnetic resonance imaging (MRI) with or without mammography could inform discussions about supplemental MRI in women with dense breasts. We evaluated 52 237 women aged 40-79 years who underwent 2611 screening MRIs alone and 6518 supplemental MRI plus mammography pairs propensity score-matched to 65 810 screening mammograms. Rates per 1000 examinations of interval, advanced, and screen-detected early stage invasive cancers and false-positive recall and biopsy recommendation were estimated by breast density (nondense = almost entirely fatty or scattered fibroglandular densities; dense = heterogeneously/extremely dense) adjusting for registry, examination year, age, race and ethnicity, family history of breast cancer, and prior breast biopsy. Screen-detected early stage cancer rates were statistically higher for MRI plus mammography vs mammography for nondense (9.3 vs 2.9; difference = 6.4, 95% confidence interval [CI] = 2.5 to 10.3) and dense (7.5 vs 3.5; difference = 4.0, 95% CI = 1.4 to 6.7) breasts and for MRI vs MRI plus mammography for dense breasts (19.2 vs 7.5; difference = 11.7, 95% CI = 4.6 to 18.8). Interval rates were not statistically different for MRI plus mammography vs mammography for nondense (0.8 vs 0.5; difference = 0.4, 95% CI = -0.8 to 1.6) or dense breasts (1.5 vs 1.4; difference = 0.0, 95% CI = -1.2 to 1.3), nor were advanced cancer rates. Interval rates were not statistically different for MRI vs MRI plus mammography for nondense (2.6 vs 0.8; difference = 1.8 (95% CI = -2.0 to 5.5) or dense breasts (0.6 vs 1.5; difference = -0.9, 95% CI = -2.5 to 0.7), nor were advanced cancer rates. False-positive recall and biopsy recommendation rates were statistically higher for MRI groups than mammography alone. MRI screening with or without mammography increased rates of screen-detected early stage cancer and false-positives for women with dense breasts without a concomitant decrease in advanced or interval cancers.

When MRI would be useful in patients without evidence of sacroiliitis on radiographs?

We aimed to identify when magnetic resonance imaging (MRI) would be useful to diagnose patients with suspected axial spondyloarthropathy (AxSpA) without evidence of sacroiliitis on radiographs. We retrospectively reviewed electronic medical records of patients who underwent pelvis MRI after radiographs at the rheumatology clinic in a single tertiary center in Korea. Patients underwent imaging from January 2020 to July 2022. We collected data including complete blood count, erythrocyte sedimentation rate, C-reactive protein (CRP), human leukocyte antigen (HLA)-B27, history of acute anterior uveitis (AAU), peripheral arthritis, dactylitis, inflammatory bowel disease (IBD), enthesopathy, and psoriasis. A total of 105 patients who showed no evidence of sacroiliitis on radiographs were included. The median age of patients was 41.0 years, and 44.8% were male. Of them, 34 showed sacroiliitis on MRI (group 1), and 71 showed no evidence of sacroiliitis even on MRI (group 2). Known AxSpA-related clinical features including AAU, peripheral arthritis, dactylitis, IBD, enthesopathy, and psoriasis were not different between the two groups. HLA-B27 positivity (79.4% vs. 40.0%, p < 0.001), median white blood cell count (7700 vs. 6300, p = 0.007), mean platelet count (307.7 ± 69.7 vs. 265.3 ± 68.9 × 103/µL, p = 0.005), and median CRP level (0.38 vs. 0.10, p = 0.001) showed significant differences between the two groups. In a multivariate analysis, HLA-B27 positivity and platelet count were significantly associated with sacroiliitis on MRI. In our cohort, sacroiliitis was observed on MRI in one-third of patients without radiographic evidence. MRI could be recommended to evaluate sacroiliitis in patients with positive HLA-B27 and a high platelet count.

A Novel Method for Assessing the 3-dimensional Morphology of Cartilaginous Acetabulum Via Childhood Magnetic Resonance Imaging.

Periarticular cartilage is abundant in children, making evaluations of 3-dimensional (D) cartilaginous acetabular morphology using x-ray or computed tomography (CT) difficult. The study aimed to visualize the 3D cartilaginous acetabular morphology in normal children and patients with pediatric developmental dysplasia of the hip (DDH). Magnetic resonance imaging (MRI) of 17 female children without acetabular dysplasia at 7.5 years and CT of 33 normal female adolescents with mature bones at 14.6 years were used as controls. Subjects were 26 female patients with unilateral DDH who underwent angulated Salter innominate osteotomy (A-SIO) at 5.5 years. Preoperative and postoperative MRIs were performed at 5.2 and 7.0 years, respectively. The MRI sequence was 3D-MEDIC. The medial intersection (point A) of the line connecting the centers of the bilateral femoral head and the femoral head were defined as point zero. The 3D coordinates (X, Y, Z) of the cartilaginous acetabular edge (point C) from anterior to posterior were calculated. Subsequently, a 3D scatter plot was created using 3D graph software. The subjects were divided into 6 groups, including control MRI, control CT, unaffected DDH before and after A-SIO, and affected DDH before and after A-SIO. The femoral head coverage ratio (FHCR: AC/AB) was used to quantify coverage and was compared in each group. In the control MRI group, the acetabular coverage was small anteriorly, largest anterolaterally, and gradually decreased posteriorly, similar to the bony acetabulum in adolescents. In the affected DDH before A-SIO group, the coverage was significantly lower than that of the control MRI and unaffected DDH groups. After A-SIO, the morphology improved beyond the unaffected DDH and the control MRI group. The global defect of the cartilaginous acetabulum in the affected DDH group was significantly improved to normal morphology after A-SIO. Evaluating the cartilaginous acetabulum using MRI was useful for assessing hip morphology in childhood. Level III-retrospective comparative study.

P11.03.A DOES REGULAR SURVEILLANCE IMAGING IMPROVE SURVIVAL IN GLIOBLASTOMA? RESULTS FROM A NATIONAL, MULTI-CENTRE COHORT STUDY (INTERVAL-GB)

Abstract BACKGROUND Glioblastoma is the most common malignant primary brain tumour in adults and is usually incurable. Post-operative magnetic resonance imaging (MRI) is used to assess extent of resection, and subsequent follow-up MRI is used to monitor response to treatment and to detect progression. The benefit of regular, scheduled follow-up MRI on patient management and outcomes is unclear. MATERIAL AND METHODS In this multi-centre, retrospective observational cohort study we included patients with a histopathologically confirmed glioblastoma, operated between August 31, 2018 and February 1, 2019 who received any adjuvant oncological treatment. Follow-up MRI schedules, indications, and clinical outcomes were collected. The primary objective was to investigate the follow-up MRI surveillance practice after surgery for glioblastoma and assess compliance with recommendations from the National Institute for Health and Care Excellence (NICE) (Post-operative scan &amp;lt;72 hrs, MRI every 3-6 months). The secondary objectives were to determine indications for MRI scans and the association on overall survival (OS) and progression-free survival (PFS). RESULTS 754 patients, with a median age of 63 years (range: 21-84) from 26 neuro-oncology centres were included. Most patients had post-operative MRI within 72 hours of surgery (88.1%, N=407/462). The median number of subsequent follow-up MRI was 1 (Interquartile range 0-4). 28.1% of patients had follow-up MRI in accordance with NICE recommendations (N=212/754). Patients in this group were more likely to receive second-line chemotherapy (28.6% vs 19.5%, P=0.009). The median follow-up period was 10.5 months (IQR 5.3-19.4 months). Median overall survival was 15.1 months (95% CI 12.9-17.3) in the scheduled MRI group and 9.1 months (95% CI 7.8-10.4) in the non-compliant group. On multivariable cox regression analysis, regular, scheduled MRI was independently associated with longer overall survival (HR 1.67, 95% CI 1.33-2.10, P&amp;lt;0.001), but not PFS (HR 1.20, 95% CI 0.98-1.47, P=0.074). Patients with progression first detected on scheduled imaging had a significantly longer OS (18.4 vs 15.6 months, P=0.013) and PFS (9.9 months vs 7.9 months, P=0.041). CONCLUSION Following regular scheduled surveillance follow-up MRI for glioblastoma is associated with longer overall survival. Prospective trials are needed to determine whether regular or symptom-directed MRI influences survival outcomes and quality of life.

Breast Magnetic Resonance Imaging for Preoperative Evaluation of Breast Cancer: A Systematic Review and Meta-Analysis.

Purpose: Preoperative breast magnetic resonance imaging (MRI) is known to detect additional cancers that are occult on mammography and ultrasound. There is debate as to whether these additional lesions affect clinical outcomes. The objective of this systematic review was to summarize the evidence on whether additional information on disease extent obtained with preoperative breast MRI in patients with newly diagnosed breast cancer affects surgical management, rates of recurrence, survival, re-excision, and early detection of bilateral cancer. Methods: Embase, MEDLINE, and Cochrane Central Register of Controlled Trials were searched until January 2021 (partial update July 2022) for studies comparing outcomes with versus without pre-operative MRI. Included were both randomized controlled trials and other comparative studies provided MRI and control groups had equivalent disease and patient characteristics or methods such as multivariable analysis or propensity score matching were used to control potential confounders. Results: The search resulted in 26,399 citations, of which 8 randomized control trials, 1 prospective cohort study, and 42 retrospective studies met the inclusion criteria. Use of MRI resulted in decreased rates of reoperations (OR = 0.73, 95% CI = 0.63 to 0.85), re-excisions (OR = 0.63, 95% CI = 0.45 to 0.89), and recurrence (HR = 0.77, 95% CI = 0.65 to 0.90). Increased detection of synchronous contralateral breast cancers led to a reduction in metachronous contralateral breast cancer (HR = 0.71, 95% CI = 0.59 to 0.85). Hazard ratios for recurrence-free and overall survival were 0.77 (95% CI = 0.53 to 1.12) and 0.89 (95% CI = 0.74 to 1.07). Conclusion: This systematic review indicates substantial benefits of pre-operative breast MRI in decreasing reoperations and recurrence.

Is Breast Magnetic Resonance Imaging Superior to Sonography in Gynecomastia Evaluation and Surgery Planning.

Data on the value of magnetic resonance imaging (MRI) in the preoperative evaluation and surgery planning of gynecomastia are limited. The purpose of this study is to reveal MRI features and categories of gynecomastia and compare surgical outcomes following MRI and sonography as well as their diagnostic accuracy. The area of the gland and the whole breast on the transverse plane via nipple of MRI were measured to calculate the ratio between them. Areola, mass and branch patterns were categorized to represent three different gynecomastia type on MRI. 183 patients were included, with 38 in MRI group and 145 in sonography group. Diagnostic accuracy was assessed by the level of agreement between preoperative imaging findings and intraoperative observations. Surgical data, patients' satisfaction and complications were compared between the two groups. MRI in 75 gynecomastic breasts demonstrated the average ratio of the gland to the whole breast was 10.6%±13.3%. The most common MRI categories were branch patterns (45.3%). The diagnostic concordance rate of MRI was higher than sonography (100% vs. 86.8%, p = 0.001). Among those junior surgeons, the length of surgery was reduced in MRI group (100 min vs. 115 min, p = 0.048). There was no difference in terms of patient's satisfaction and complication rate between MRI and sonography. MRI was superior to sonography in diagnostic accuracy to assess the tissue components of gynecomastia and provided informative guidance especially for junior surgeons. Surgical outcomes were comparable regardless of the use of MRI or sonography for evaluation. IThis journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Machine learning-based radiomics analysis of preoperative functional liver reserve with MRI and CT image

ObjectiveThe indocyanine green retention rate at 15 min (ICG-R15) is a useful tool to evaluate the functional liver reserve before hepatectomy for liver cancer. Taking ICG-R15 as criteria, we investigated the ability of a machine learning (ML)-based radiomics model produced by Gd-EOB-DTPA-enhanced hepatic magnetic resonance imaging (MRI) or contrast-enhanced computed tomography (CT) image in evaluating functional liver reserve of hepatocellular carcinoma (HCC) patients.MethodsA total of 190 HCC patients with CT, among whom 112 also with MR, were retrospectively enrolled and randomly classified into a training dataset (CT: n = 133, MR: n = 78) and a test dataset (CT: n = 57, MR: n = 34). Then, radiomics features from Gd-EOB-DTPA MRI and CT images were extracted. The features associated with the ICG-R15 classification were selected. Five ML classifiers were used for the ML-model investigation. The accuracy (ACC) and the area under curve (AUC) of receiver operating characteristic (ROC) with 95% confidence intervals (CI) were utilized for ML-model performance evaluation.ResultsA total of 107 different radiomics features were extracted from MRI and CT, respectively. The features related to ICG-R15 which was classified into 10%, 20% and 30% were selected. In MRI groups, classifier XGBoost performed best with its AUC = 0.917 and ACC = 0.882 when the threshold was set as ICG-R15 = 10%. When ICG-R15 = 20%, classifier Random Forest performed best with AUC = 0.979 and ACC = 0.882. When ICG-R15 = 30%, classifier XGBoost performed best with AUC = 0.961 and ACC = 0.941. For CT groups, the classifier XGBoost performed best when ICG-R15 = 10% with AUC = 0.822 and ACC = 0.842. When ICG-R15 = 20%, classifier SVM performed best with AUC = 0.860 and ACC = 0.842. When ICG-R15 = 30%, classifier XGBoost performed best with AUC = 0.938 and ACC = 0.965.ConclusionsBoth the MRI- and CT-based machine learning models are proved to be valuable noninvasive methods for functional liver reserve evaluation.

Poster 253: Is the Use of Pretreatment Magnetic Resonance Imaging Necessary Prior to Surgery in Pediatric Tibial Spine Fractures

Objectives: Injuries to the tibial spine occur as a result of an anterior cruciate ligament (ACL) avulsion fracture from the intercondylar eminence of the proximal tibia. Similar to anterior cruciate ligament ruptures, tibial spine injuries are associated with damage to other intraarticular structures. These associated injuries are often visualized with Magnetic Resonance Imaging (MRI) obtained prior to surgery. The purpose of the study is to describe concomitant injuries visualized by a pretreatment MRI, to examine how this correlates to what is seen at the time of surgery, and to determine how a pretreatment MRI affects the time between injury and surgery as well the length of the surgical procedure itself. Our hypothesis is that a pretreatment MRI results in a longer time between injury and surgery without any affect on operating time or amount of concomitant pathology identified. Methods: Utilizing an institutional review board approved retrospective study, we identified patients under 18 years of age who underwent arthroscopic management of a tibial spine fracture over a 13 year period. Our exclusion criteria were patients with a concomitant ipsilateral lower extremity fracture or posterior cruciate ligament injury, patients with poor imaging quality, and patients with incomplete medical records. Patients were then categorized based on whether they obtained a pretreatment MRI. We then evaluated for concomitant injuries, time from injury to surgery, total room time, and tourniquet time between the groups. Results: A total of 85 patients met this inclusion criteria, of which 44 (51.7%) had a pretreatment MRI. There were no significant differences in age, gender, or Myers and McKeever grade between groups. All were treated with arthroscopic reduction and fixation. In the MRI group, there were 30 patients (68.2%) that were identified to have additional meniscal or chondral pathology. The three most common pathologies seen on MRI were lateral meniscus tears (13 patients), medial meniscus tears (6 patients), and intermeniscal ligament entrapment (6 patients). In addition, 28 patients (63.6%) were found to have a bone contusion pattern similar to that seen in ACL injuries and 17 patients (38.6%) showed signs of damage to the ACL fibers themselves. Of those 30 patients with meniscal pathology or entrapment seen on MRI, 17 patients (56.7%) were confirmed to have that pathology at the time of arthroscopy. The percentage of patients with meniscal or chondral pathology seen on arthroscopy was not significantly different between those who received a pretreatment MRI and those who did not (38.6% MRI group vs 41.5% No-MRI group p =0.79). The time from injury to surgery was significantly longer in the MRI group (19.3 days vs 10.1 days p=0.01). Both the tourniquet time (72 min vs 76 min) and operative time (83.5 min vs 90.5 min) were not significantly different(p=0.49 for tourniquet time and p=0.32 for room time). Conclusions: Over two-thirds of patients who sustained a tibial spine fracture were noted to have concomitant pathology on MRI, with 56.7% of injuries seen on MRI correlating to what was seen at the time of surgery. The use of pretreatment MRI was shown to delay surgery without any significant change in operative time, tourniquet time, or percentage of pathology identified at time of surgery. Previous studies have suggested that a pre-treatment MRI may be helpful in identifying pathology, however we believe this is the first study to determine if obtaining a pretreatment MRI influences operative time, tourniquet time, and pathology identified at time of surgery.