Accuracy Of MRI Research Articles

Accuracy of combined multi-parametric MRI and PSMA PET-CT in diagnosing localized prostate cancer: newer horizons for a biopsy-free pathway

IntroductionProstate-specific antigen (PSA) is a reliable biomarker for identification of prostate cancer, although a biopsy is still the gold standard for detecting prostate cancer. Similar to higher PIRADS lesions on MRI, the maximal standard uptake value (SUV max) on PSMA PET is linked to a higher likelihood of prostate cancer. Can an mpMRI in conjunction with PSMA PET Scan accurately predict prostate cancer and further trigger omission of biopsy similar to other solid organ urological malignancies?MethodsGa-68 PSMA PET and mpMRI were performed for each patient who was a part of this retrospective study. The PET-positive lesion's maximum standardized uptake value (SUVmax) was recorded. Prostate biopsies were performed on patients who had PSMA PET avid lesions and a PIRADS score of 4 or 5. Robot-assisted radical prostatectomy (RARP) was afterward performed on patients who had cancer on their prostate biopsy. The prostatectomy specimen's histopathological information was recorded. Cutoff values and correlations between the variables were determined using the ROC curves and Pearson's correlation test.ResultOn the basis of suspicious DRE findings or elevated PSA, 70 men underwent mpMRI and PET scans. PIRADS 4 patients had a median (IQR) SUVmax of 8.75 (11.95); whereas, PIRADS 5 patients had an SUVmax of 24.5 (22). The mean SUVmax for patients whose biopsies revealed no cancer was 6.25 ± 1.41. With an AUC of 0.876 on the ROC curve, it was found that there was a significant positive correlation between the results of the mpMRI and PET scans and those of the histopathological investigation. A SUVmax ≥ 8.25 on PSMA PET for a PIRADS 4/5 lesion on mpMRI will aid in correctly predicting malignancy, with a sensitivity of 82.8% and specificity of 100%.ConclusionThe findings of this study were positive and indicated that patients with a high suspicion of prostate cancer on mpMRI and PSMA PET (PIRADS ≥ 4 and SUVmax ≥ 8.25). This study substantiates the fact that a combination of mpMRI and PSMA PET can accurately predict localized prostate cancer.

Multiparametric Magnetic Resonance Imaging of Penile Cancer: A Pictorial Review.

The role of multiparametric magnetic resonance imaging (mpMRI) in assessing penile cancer is not well defined. However, this modality may be successfully applied for preoperative staging and patient selection; postoperative local and regional surveillance; and assessments of treatment response after oncological therapies. Previous studies have been mostly limited to a few small series evaluating the accuracy of MRI for the preoperative staging of penile cancer. This review discusses the principles of non-erectile mpMRI, including functional techniques and their applications in evaluating the male genital region, along with clinical protocols and technical considerations. The latest clinical classifications and guidelines are reviewed, focusing on imaging recommendations and discussing potential gaps and disadvantages. The development of functional MRI techniques and the extraction of quantitative parameters from these sequences enables the noninvasive assessment of phenotypic and genotypic tumor characteristics. The applications of advanced techniques in penile MRI are yet to be defined. There is a need for prospective trials and feasible multicenter trials due to the rarity of the disease, highlighting the importance of minimum technical requirements for MRI protocols, particularly image resolution, and finally determining the role of mpMRI in the assessment of penile cancer.

Abstract 13615: Diagnostic Accuracy of Cardiac MRI for Detecting Wall Motion Abnormalities and Coronary Artery Stenosis - A Systematic Review and Umbrella Meta-Analysis

Introduction: Conventional coronary angiography (CCA) is the gold standard for the diagnosis of coronary artery disease (CAD). It is an invasive test and carries risks. Increased mortality is linked with reduced coronary flow, thus aggressively measuring coronary flow is important. Cardiac MRI (cMRI) is an emerging non-invasive test that can also help in assessing ventricular function, myocardial perfusion, and detecting anomalies. Aim: We aimed to analyze the diagnostic accuracy of cMRI compared to CCA through an umbrella meta-analysis. Methods: We searched PubMed articles comparing the diagnostic accuracy of cMRI with CCA in patients having CAD published from 2000 to 2022 according to PRISMA guidelines. We used the generic inverse variance method to pool sensitivity (SN), specificity (SP), negative likelihood ratio, positive likelihood ratio, and diagnostic odds ratio (DOR) with 95% confidence interval keeping alpha criteria of 0.05 as significant. RevMan 5.4 was used to calculate random effects models. Results: In this umbrella meta-analysis, 9 studies with 14615 patients met inclusion criteria. Overall pooled SN was 0.88 (95% CI: 0.87-0.90), SP was 0.85 (0.81-0.89), PLR was 6.07 (5.02-7.33), NLR was -1.99 (-2.10 to -1.87), and DOR 38.94 (31.96-47.46). (p<0.00001) Conclusion: The diagnostic accuracy of a non-invasive, cMRI is comparable, if not superior to an invasive test like CCA.

MRI and PET/CT in the assessment of lymph node metastases in head and neck cancer

The aim of this study is to present the diagnostic accuracy of MRI and PET/CT in the evaluation of cervical lymph nodes in patients with head and neck cancer (HNC). Data of 114 patients who underwent MRI and PET/CT prior to surgery in the time period between January 2010 and September 2021 in our center is analyzed retrospectively. Histopathological results of surgical preparations serve as the gold standard. The mean time from MRI to surgery is 22.9 (± 18.7) days, and from PET/CT to surgery 21.7 (± 19.9) days. Sensitivities of 80.4% and 80.4%, specificities of 85.7% and 87.3%, PPVs of 82.0% and 83.7% and NPVs of 84.4% and 84.6% are registered for MRI and PET/CT, respectively. 37 false results are further analyzed with respect to side and level of the affected lymph node, as well as intersections of the two imaging modalities. In 29 patients (25.4%), additional findings are described in PET/CT, 7 (6.1%) of which were histologically confirmed to be further malignancies. A combination of both MRI and PET/CT imaging modalities could improve diagnostic accuracy, especially with regard to sensitivity. A notable number of additional findings in whole body acquisition leads to the potential diagnosis of further malignancies.

Value of Non-Contrast-Enhanced Vessel Wall MR Imaging in Assessing Vascular Invasion of Retroperitoneal Tumors.

Due to their location and growth patterns, retroperitoneal tumors often involve the surrounding blood vessels. Clinical decisions on a proper treatment depend on the information on this condition. Evaluation of blood vessels using non-contrast-enhanced vessel wall MRI may provide noninvasive assessment of the extent of tumor invasion to assist clinical decision-making. To investigate the performance and potential of non-contrast-enhanced vessel wall MRI in evaluating the degree of vessel wall invasion of retroperitoneal tumors. Prospective. Thirty-seven participants (mean age: 60.59 ± 11.77 years, 59% male) with retroperitoneal tumors close to vessels based on their diagnostic computer tomography. 3 T; vessel wall MRI sequences: two-dimensional T2-weighted MultiVane XD turbo spin-echo (2D-T2-MVXD-TSE) and three-dimensional T1-weighted motion sensitized driven equilibrium fat suppression turbo spin-echo (3D-T1-MSDE-TSE) sequences; conventional MRI sequences: T2-weighted fat suppression turbo spin-echo (T2-FS-TSE), T2-weighted turbo spin-echo (T2-TSE), modified Dixon T1-weighted fast field echo (T1-mDixon-FFE), and diffusion-weighted echo planar imaging (DWI-EPI) sequences. All patients underwent preoperative imaging using both non-contrast conventional and vessel wall MRI sequences. Images obtained from conventional and vessel wall MRI sequences were evaluated independently by three junior radiologists (3 and 2 years of experience in reading MRI) and reviewed by one senior radiologist (25 years of experience in reading MRI) to assess the degree of vessel wall invasion. MRI were validated results from the clinical standard diagnosis based on surgical confirmation or histopathological reports. Interobserver agreement was determined based on the reports from three readers with similar years of experiences. Intraobserver variability was assessed based on categorizing and recategorizing the vessels of 37 patients 1 month apart. Intra-class correlation efficient (ICC), Chi-square test, McNemar test, area under the receiver-operating characteristic curve (AUC), Delong test, P < 0.05 was considered significant. The accuracy of vessel wall MRI (91.96%, 95% CI: 85.43-95.71; 103 of 112) in detecting the degree of vessel wall invasion was significantly higher than that of conventional MRI (75%, 95% CI: 66.24-82.10; 84 of 112). The interobserver variability or reproducibility in categorization of the degree of vascular wall invasion was good in evaluating images from conventional and vessel wall MRI sequences (ICC = 0.821, 95% CI: 0.765-0.867 and ICC = 0.881, 95% CI: 0.842-0.913, respectively). Diagnosis of vessel wall invasion of retroperitoneal tumors and assessment of its severity can be improved by using non-contrast-enhanced vessel wall MRI. 1 TECHNICAL EFFICACY: Stage 3.

Accuracy of low-field magnetic resonance imaging for differentiating intervertebral disc extrusions and protrusions at the lumbosacral disc space in dogs.

MRI features differentiating extrusion from protrusion in thoracolumbar discs have been published, however little specifically evaluates the lumbosacral disc. The high prevalence of degenerative changes in apparently normal animals complicates assessment of this region and features relevant elsewhere in the spine may not apply. The aims of this study were to determine the accuracy of MRI in differentiating IVDE and IVDP at the lumbosacral disc space in dogs and determine which MRI characteristics discriminate between IVDE and IVDP. MRI examinations from dogs with surgically confirmed IVDE or IVDP at the lumbosacral disc space were collected retrospectively (2011-2019). Two radiologists independently recorded a diagnosis of IVDE or IVDP, gave a confidence rating, and evaluated specific MRI features. Univariable statistical analysis was performed to identify which MRI characteristics might help distinguish IVDE from IVDP. 117 dogs with lumbosacral IVDE (n = 16) or IVDP (n = 101) were included. Features associated with IVDE were in concordance with previous studies and included interruption of the dorsal annulus, suspected epidural hemorrhage, dispersed (rather than confined) intervertebral disc herniation on T2W sagittal images, lateralized intervertebral disc herniation and displacement of the cauda equina. Overall diagnostic accuracy was 68.8% and interobserver agreement was fair (κ = 0.37), which is lower than has been reported in thoracolumbar disc herniation, but accuracy increased to 85.3% with substantially improved agreement (κ = 0.87) in "confident" diagnoses. MRI characteristics used in differentiating thoracolumbar IVDE and IVDP can be extrapolated to the lumbosacral intervertebral disc space, but diagnostic accuracy in low-field MRI is lower than previously reported in herniations involving the thoracolumbar spine.

Diagnostic accuracy of MRI for detection of occult instability of type I anterior to posterior pelvic injuries

Type I Young and Burgess anterior posterior compression (APC) pelvic injuries have been classically managed non operatively due to theoretical integrity of sacroiliac joint ligaments (SIJL), though examination under anesthesia (EUA) has been proven occult mechanical instability in up to 50% of these injuries. We sought to determine the diagnostic accuracy of magnetic resonance (MRI) for detection of occult instability on APC-I injuries when compared to EUA.Methods: Diagnostic test study of prospectively recruited patients admitted with APC-I pelvic injuries between 2015 and 2022. All patients consented to participate in this study were subjected to MRI and EUA. The evaluators of each of these tests were blinded. On MRI evaluation, SIJL were considered compromised when unilateral injury to anterior SIJL was visualized in three or more consecutive images or in bilateral injuries, when injury to the anterior SIJL in two or more consecutive images on each side was observed. Positive EUA was considered a symphyseal diastasis over 25 mm on stress fluoroscopy. Demographic data was collected as recruited and sensitivity, specificity, accuracy, and positive and negative predictive values were calculated. Confidence interval was set at 95%. EUA was considered the gold standard in statistical analysis.Results: A total of 32 patients mean aged 36 (24–61) years were included. Mean symphyseal diastasis at admission was 17.58 (11 - 25) mm. The median time from injury to EUA was 5 (0–21) days. Positive EUA was observed on 20 patients and 25 patients presented compromised SIJL. MRI presented a sensitivity of 95% (75.13% - 99.87%), specificity of 50% (21.09% - 78.91%), positive-predictive value of 73% (60.61% to 82.93%), negative-predictive value of 87% (48.66% - 98.08%).Conclusion: Injury to SIJL on MRI presented an accuracy of 77% (58.29% - 89.64%) for the detection of occult pelvic instability on EUA.

Problem-solving Breast MRI.

Breast MRI has high sensitivity and negative predictive value, making it well suited to problem solving when other imaging modalities or physical examinations yield results that are inconclusive for the presence of breast cancer. Indications for problem-solving MRI include equivocal or uncertain imaging findings at mammography and/or US; suspicious nipple discharge or skin changes suspected to represent an abnormality when conventional imaging results are negative for cancer; lesions categorized as Breast Imaging Reporting and Data System 4, which are not amenable to biopsy; and discordant radiologic-pathologic findings after biopsy. MRI should not precede or replace careful diagnostic workup with mammography and US and should not be used when a biopsy can be safely performed. The role of MRI in characterizing calcifications is controversial, and management of calcifications should depend on their mammographic appearance because ductal carcinoma in situ may not appear enhancing on MR images. In addition, ductal carcinoma in situ detected solely with MRI is not associated with a higher likelihood of an upgrade to invasive cancer compared with ductal carcinoma in situ detected with other modalities. MRI for triage of high-risk lesions is a subject of ongoing investigation, with a possible future role for MRI in decreasing excisional biopsies. The accuracy of MRI is likely to increase with the use of advanced techniques such as deep learning, which will likely expand the indications for problem-solving MRI. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Diagnostic validity of MRI for central nervous system tuberculosis: protocol for a systematic review and meta-analysis

IntroductionCentral nervous system tuberculosis (CNSTB) is a severe condition, sometimes associated with a poor prognosis. Early diagnosis of CNSTB remains challenging, considering that conventional methods lack sensitivity or might lead...

Magnetic resonance imaging accuracy in staging early and locally advanced rectal cancer

IntroductionMagnetic Resonance Imaging (MRI) is the standard pretreatment staging in patients with rectal cancer. Accurate tumor staging is paramount to determining the appropriate treatment course for patients diagnosed with rectal cancer. The current study aims to re-evaluate the accuracy of pre-operative MRI in staging of both early and locally advanced rectal cancer following completion of neoadjuvant therapy (NAT) compared to the pathologic stage. MethodsA retrospective review of patients treated for rectal cancer between 2015 and 2020 at a single academic institution. All patients underwent rectal cancer protocol MRIs before surgical resection. Analysis was carried out in two groups: early rectal cancer: T1/2 N0 tumors with upfront surgical resection (N = 40); and locally advanced disease: T3 or greater or N+ disease receiving NAT, with restaging MRI following NAT (n = 63). Results103 patients were included in analysis. MRI accuracy in early tumors was 35% ICC = 0.52 (95% CI 0.25–0.71) T stage and 66% ICC = 0 (95% CI -0.24, 0.29) for 29 patients with nodal data for N stage. There was 28% understaging of T2 tumors and 34% understaging of N0 stage by MRI. Post NAT MRI had 44% accuracy ICC = 0.57 (95% CI -0.15-0.20) T stage and 60% accuracy ICC = 0.32 (95% CI 0.08–0.52) N stage. Tumor invasion was overstaged on MRI: 40% T2, 29% T3, 90% T4. Nodal inaccuracy was due to overstaging, 61% N1, 90% N2. ConclusionsIn locally advanced rectal cancer MRI overstaged tumors, this could be due to the continued effect of NAT from MRI to resection. This overstaging is of little clinical significance as it doesn't alter the treatment plan, except in cases of complete clinical response. In early rectal cancer, MRI had limited accuracy compared to pathology, understaging a quarter of patients who would benefit from NAT before surgery. Other adjunct imaging modalities should be considered to improve accuracy in staging early rectal cancer and consideration of complete response and enrollment in watch and wait protocols.

P11.07.A PERFUSION-MRI BASED DIFFERENTIATION BETWEEN EARLY TUMOR PROGRESSION AND PSEUDOPROGRESSION IN GLIOBLASTOMA AND ITS USE IN CLINICAL PRACTICE

Abstract BACKGROUND Post-gadolinium MRI is considered the mainstay of radiological monitoring of treatment effects in patients with a glioblastoma. However, the radiotherapy(RT)-induced abnormality, pseudoprogression, is difficult to distinguish from real tumor growth. Perfusion MRI (pMRI), including Arterial Spin Labeling (ASL) and Dynamic Susceptibility Contrast (DSC), may help in this differentiation. Evaluation of RT effects is usually discussed during multidisciplinary team meetings (MDTM), after which a decision regarding (dis)continuation of anti-tumor treatment is made. It is currently unknown whether pMRI impacts such treatment decisions. This study evaluated how accurate pMRI and the MDTM are in distinguishing tumor progression from pseudoprogression in glioblastoma. MATERIAL AND METHODS Population and outcome: Glioblastoma patients who received postoperative RT were retrospectively included from 2015 to 2020. ASL, DSC, FLAIR and post-gadolinium 3D-T1 at 3 months post-RT were visually scored for probability of radiological tumor progression. These radiological scores, as well as the outcome of MDTM, were compared to the final outcome (i.e. tumor progression or pseudoprogression) set at 9 months after RT initiation. Statistical analysis: Diagnostic accuracy of pMRI, conventional MRI and MDTM was assessed by 2x2 tables, sensitivity and specificity (including AUC values). In case the MDTM was inconclusive, subsequent analysis was used to determine whether pMRI has additional value. A multivariable logistic regression model was constructed to assess which clinical parameters (age, surgery type, IDH mutation status, MGMT methylation status, KPS score, chemotherapy and pMRI evaluation) were associated with the outcome of the MDTM assessment. RESULTS Sixty-five patients with a glioblastoma met the inclusion criteria (40 male, mean age 60+/-13 years, median KPS of 90). For all METHODS , the sensitivity for detecting true disease progression was poor to moderate (32-62%). Although sensitivity was higher when adding pMRI to conventional imaging (56% versus 32%), specificity was lower (80% versus 93%). AUC values were comparable (range 0.63-0.74), but highest for MDTM evaluation (0.74). For the 26% of patients where MDTM was inconclusive, pMRI shows increased sensitivity compared to conventional MRI in detecting tumor progression (respectively 36% versus 0%). The multivariable regression analysis showed significant associations for KPS score (OR = 0.84 (95% CI: 0.77-0.91)) and radiological assessment based on pMRI with MDTM outcome (OR = 0.09 (95% CI: 0.02-0.52)). CONCLUSION This study shows that perfusion MRI has added value for detection of tumor progression within the MDTM assessment in clinical decision-making for glioblastomas, especially when the MDTM outcome is uncertain. For this decision, the role of perfusion MRI and the KPS score are most important.

Biceps Pulley Lesions: Diagnostic Accuracy of Nonarthrographic Shoulder MRI and the Value of Various Diagnostic Signs.

There is limited data in the literature regarding the role of nonarthrographic MRI for detecting biceps pulley (BP) lesions. To assess the accuracy of nonarthrographic MRI for detecting BP lesions, and to evaluate the diagnostic value of various MRI signs (superior glenohumeral ligament discontinuity/nonvisibility, long head of biceps (LHB) displacement sign or subluxation/dislocation, LHB tendinopathy, and supraspinatus and subscapularis tendon lesions) in detecting such lesions. Retrospective. 84 patients (32 in BP-lesion group and 52 in BP-intact group-as confirmed by arthroscopy). 1.5-T, T1-weighted turbo spin echo (TSE), T2-weighted TSE, and proton density-weighted TSE spectral attenuated inversion recovery (SPAIR) sequences. Three radiologists independently reviewed all MRI data for the presence of BP lesions and various MRI signs. The MRI signs and final MRI diagnoses were tested for accuracy regarding detecting BP lesions using arthroscopy results as the reference standard. Furthermore, the inter-reader agreement (IRA) between radiologists was determined. Student's t-tests, Chi-squared, and Fisher's exact tests, and 4-fold table test were used. The IRA was calculated using Kappa statistics. A P-value <0.05 was considered statistically significant. The sensitivity, specificity, and accuracy of nonarthrographic MRI for detecting BP lesions were 65.6%-78.1%, 90.4%-92.3%, and 81%-86.9%, respectively. The highest accuracy was noticed for the LHB displacement sign (84.5%-86.9%), and the highest sensitivity was registered for the LHB tendinopathy sign (87.5%). Furthermore, the highest specificity was observed for the LHB displacement sign and LHB subluxation/dislocation sign (98.1%-100%). The IRA regarding final MRI diagnosis and MRI signs of BP lesions was good to very good (κ = 0.76-0.98). Nonarthrographic shoulder MRI may show good diagnostic accuracy for detecting BP lesions. The LHB displacement sign could serve as the most accurate and specific sign for diagnosis of BP lesions. 3 TECHNICAL EFFICACY: Stage 2.

Validity of Magnetic Resonance Imaging Report of Meniscal Tear in Relationship to Arthroscopic Findings

Objective: To determine the diagnostic accuracy of magnetic resonance imaging in assessment of meniscal tear taking arthroscopy as gold standard Methodology: This cross-sectional study including 180 participants from different age groups was conducted at Shifa international hospital, Islamabad from June 2021- December 2021. Patients underwent both MRI and Arthroscopy and the results were compared. Data analysis was done using SPSS 22, quantitative variables were represented as mean and standard deviation, for qualitative variables frequencies and percentages were used for representation. Sensitivity, specificity, NPV, PPV and diagnostic accuracy of MRI was determined taking Arthroscopy as gold standard. For data analysis SPSS version 22 was used and the results were depicted using frequencies and percentages. Results: 180 participants were included in the research out of which males were predominant with more than ¾ of the study population. Trauma and sports were the common cause of injuries. Sensitivity and specificity were found to be 95.95% and 69.13% respectively. PPV and NPV were 62.91% and 86.20% respectively. Patients were categorized in three groups with respect to age: middle aged (31-60 years) patients were greater in number and comprised more ¾ of the total. Conclusion: MRI is a good, accurate non-invasive modality for the patients with meniscal tears while arthroscopy Still remains a gold standard.

An Updated Review on Imaging and Staging of Anal Cancer-Not Just Rectal Cancer.

This review discusses the histology, MR technique, diagnosis, staging, and treatment of anal cancer, with a particular focus on the differences in TNM staging between anal squamous-cell carcinoma (ASCC) and rectal adenocarcinoma. To conduct this updated review, a comprehensive literature search was performed using prominent medical databases, including PubMed and Embase. The search was limited to articles published within the last 10 years (2013-2023) to ensure their relevance to the current state of knowledge. (1) articles that provided substantial information on the diagnostic techniques used for ASCC, mainly focusing on imaging, were included; (2) studies reporting on emerging technologies; (3) English-language articles. articles that did not meet the inclusion criteria, case reports, or articles with insufficient data. The primary outcome of this review is to assess the accuracy and efficacy of different diagnostic modalities, including CT, MRI, and PET, in diagnosing ASCC. The secondary outcomes are as follows: (1) to identify any advancements or innovations in diagnostic techniques for ASCC over the past decade; (2) to highlight the challenges and limitations of the diagnostic process. ASCC is a rare disease; however, its incidence has been steadily increasing. Primary staging and assessment after chemoradiation therapy are commonly performed using MRI, which is considered to be the preferred imaging modality. CT and PET/CT are useful in evaluating lymph node metastases and distant metastatic disease. ASCC and rectal adenocarcinoma are the most common histological subtypes and are typically indistinguishable on MRI; therefore, a biopsy prior to imaging is necessary to stage the tumor accurately and determine the treatment approach.

Evaluating the use of machine learning in endometrial cancer: a systematic review

ObjectiveTo review the literature on machine learning in endometrial cancer, report the most commonly used algorithms, and compare performance with traditional prediction models.MethodsThis is a systematic review of the literature...

The Diagnostic Accuracy of Different MRI Sequences for Different Meniscus Lesions: A Meta-analysis.

It is still uncertain to determine the exact diagnostic accuracy of MRI for medial meniscus (MM) tear, lateral meniscus (LM) tear and MM posterior root tear (MMPRT) at different magnetic field intensities (MFIs), different sequences and different publication dates. This study aimed to identify the diagnostic performance of MRI for different meniscus lesions at different MFIs, different sequences and different publication dates, and also to compare it with physical examination. PubMed, Embase, Ovid database, Biosis Previews, Cochrane library, Web of Sciences and manual searching were performed from 1 January 2000 to 31 December 2021. Prospective studies of meniscus injuries examined by physical examination, MRI and arthroscopy were included. Thirteen studies with 1583 meniscal tears were included. The pooled sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR-), diagnostic odds ratio (DOR) and area under curve (AUC) were 87% (95% confidence interval (CI), 86-89%), 82% (80-83%), 7.44 (5.11- 10.75), 0.18 (0.14-0.23), 45.95 (26,68-79.15) and 0.93, respectively. The pooled specificity between MM and LM (p = 0.015), the pooled sensitivity and LR- between MM and MMPR (p = 0.031), different MRI sequences (p = 0.035, p = 0.027), and the accuracy of less than 1.5T and 3.0T (p = 0.04), 1.5T and 3.0T (p = 0.035) were statistically different. There was no publication bias (p = 0.54). MRI performed well in the diagnosis of MM tear, LM tear and MMPRT, and the diagnostic performance of physical examination is similar to MRI. The diagnostic accuracy of 3.0T is the highest, and the -weighted imaging (SWI) sequence may be beneficial for diagnosing meniscus tear. However, there are not enough evidence to prove that recent studies are significantly better than previous ones.

471 Accuracy of Preoperative MRI for Rectal Cancer: A Retrospective Study at a District General Hospital

Abstract Aim To investigate the accuracy of preoperative MRI for rectal cancer in the form of sensitivity, specificity, positive predictive value and negative predictive value. Method The retrospective study included a cohort of 47 patients of rectal cancer from April 2017 to March 2022 who were treated with upfront surgery. With histopathology taken as standard the accuracy of preoperative MRI was calculated. Results The records of 47 rectal cancer patients were analysed who were offered primary surgery. The sensitivity and specificity of MRI for T1-T4 were 60%, 19%, 94% and 100% and 97%, 84%, 48% and 100% respectively. The sensitivity and specificity of N0- N2 staging were 46%, 57% and 50% and 61%, 53% and 95% respectively. The positive predictive value and negative predictive value of MRI for T and N staging were 69%, 85%, 44% and 77% respectively. Conclusions In our study, the results were not at par with other national and international studies. MRI is a useful tool for planning management of rectal cancer patients. The accurate preoperative staging is very important for planning the management of these patients.

POSITIVE PREDICTIVE VALUE OF TRANSCRANIAL ULTRASOUND IN EVALUATION OF HYPOXIC-ISCHEMIC ENCEPHALOPATHY KEEPING MRI AS A GOLD STANDARD

The retrospective study was conducted in the Department of Radiology, Combined Military Hospital, from January 2023 to June 2023 to compare the diagnostic accuracy of TUCS and MRI to assess HIE and evaluate the pros and cons of both imaging modalities. A total of 50 neonates were included in the study. All patients underwent physical examination, and detailed history was recorded. MRI and TCUS were performed on all patients. Results showed that 33 of 50 patents were diffusion restricted. Thirty-two cases were TCUS positive, and 18 were TCUS negative. Correlated to DWI, its sensitivity was 88.3%, specificity 100%, positive predictive value (PPV) 100%, negative predictive value (NPV) 79%, and diagnostic accuracy 91.7%. Among 48 MRS-positive patients, 41 were TCUS-positive, and 9 were negative. Correlated to MRS, its sensitivity was 89.5%, specificity 100%, PPV 100%, NPV 28.7%, and diagnostic accuracy 90%. TCUS is a simple imaging modality with good sensitivity for periventricular leukomalacia and hemorrhage. However, its less sensitive and detection of lesions of the brainstem and cerebral convexity. MRI has higher specificity and sensitivity for detecting injury caused by HIE. It provides soft tissue contrast and information about the site and extent of injury.

Boosting quantification accuracy of chemical exchange saturation transfer MRI with a spatial-spectral redundancy-based denoising method.

Chemical exchange saturation transfer (CEST) is a versatile technique that enables noninvasive detections of endogenous metabolites present in low concentrations in living tissue. However, CEST imaging suffers from an inherently low signal-to-noise ratio (SNR) due to the decreased water signal caused by the transfer of saturated spins. This limitation challenges the accuracy and reliability of quantification in CEST imaging. In this study, a novel spatial-spectral denoising method, called BOOST (suBspace denoising with nOnlocal lOw-rank constraint and Spectral local-smooThness regularization), was proposed to enhance the SNR of CEST images and boost quantification accuracy. More precisely, our method initially decomposes the noisy CEST images into a low-dimensional subspace by leveraging the global spectral low-rank prior. Subsequently, a spatial nonlocal self-similarity prior is applied to the subspace-based images. Simultaneously, the spectral local-smoothness property of Z-spectra is incorporated by imposing a weighted spectral total variation constraint. The efficiency and robustness of BOOST were validated in various scenarios, including numerical simulations and preclinical and clinical conditions, spanning magnetic field strengths from 3.0 to 11.7 T. The results demonstrated that BOOST outperforms state-of-the-art algorithms in terms of noise elimination. As a cost-effective and widely available post-processing method, BOOST can be easily integrated into existing CEST protocols, consequently promoting accuracy and reliability in detecting subtle CEST effects.

Role of MRI Diffusion Tensor Imaging in Early Diagnosis of Cervical Spondylotic Myelopathy (CSM)

Abstract Background and Purpose Cervical spondylotic myelopathy (CSM) is a common degenerative disorder of the cervical spine and is considered as the most common cause of spinal cord dysfunction in older individuals worldwide. Assessing the severity of the disease objectively remains a challenge and there is still remaining controversy in terms of the optimal timing and indications for surgical intervention. The conventional MRI is the gold standard for radiographic evaluation of the spinal cord; however, it cannot assess the underlying microstructural deficits of the spinal cord and it has a limited application in determining prognosis and recovery of the disease [1]. We sought to assess the utility of MR diffusion tensor imaging as an imaging technique in clinically suggested CSM patients by obtaining the microstructural parameters (Fractional anisotropy; FA and apparent diffusion coefficient; ADC) in the cervical spinal cord segments. Patient &amp; methods our study was a prospective cross-sectional study including 40 patients with clinical manifestations of cervical spondylotic myelopathy. The patients were sorted according to the European myelopathy score into three categories as follows: grade 1 (with mild symptoms), grade 2 (with moderate symptoms) and grade 3 (with severe symptoms). All the patients were investigated with a 1.5 T MRI unit acquiring conventional MRI and DTI sequences. FA and ADC values at each spinal segment from C2/C3 to C6/C7 were generated and measured using manual drawing of multiple ROIs within the cervical cord in the sagittal and axial combined anatomical and color-coded images. For each of these cases, the patient’s age, gender, DTI parameters at each spinal segment level, maximum compression level, conventional T2WI characteristics and EMS score were recorded, analyzed and compared. Results The study included 23 females (57.5%) and 17 males (42.5%). Their age ranged from 30 to 72 years with a mean age of 47.3 ± 9.79 years. The study revealed a significant difference in the mean FA and ADC values between stenotic and non-stenotic segments of the cervical spinal cord. There was a significant correlation between the European myelopathy score and DTI parameters (FA and ADC). FA and ADC values performed better in recognizing myelopathic changes in patients who were classified as grade 1 according to EMS compared to conventional MRI T2WI which performed very poorly in recognizing myelopathy changes in the same patients, therefore DTI indices were more sensitive in the detection of CSM patients compared to conventional MRI especially in early myelopathic stages. T2 weighted images were highly significant in recognizing myelopathy changes in patients who were classified as grade 3 according to EMS. The CSM patients had significant FA decrease and ADC increase at the most compressed part of the cervical spinal cord and there was a significant correlation between the number of patients who had myelopathic changes by DTI parameters and the severity of disease. The FA sensitivity and specificity in recognition of myelopathic changes were 73.5% and 83.3% respectively and the ADC sensitivity and specificity were 100% and 70.6% respectively. Conclusion In conclusion, diffusion tensor imaging enhances the efficacy and accuracy of MRI in the diagnosis of cervical spondylotic myelopathy. Therefore, it can be used as a non-invasive modality for detection of the spondylotic myelopathy changes in the early stages helping to decide the appropriate timing of decompression surgery before attaining the irreversible chronic changes. Abbreviations ADC: Apparent diffusion coefficient; CSM: Cervical spondylotic myelopathy; DTI: Diffusion tensor imaging; FA: Fractional Anisotropy; EMS: European myelopathy score