Abbreviated MRI Protocol Research Articles

Refining MRI Protocols for Endometriosis: A Comparative Study of Abbreviated and Full MRI Sequences.

Endometriosis is a significant cause of chronic abdominal pain and infertility in females, often overlooked due to its resemblance to other abdominopelvic pathologies. This study aims to compare the diagnostic performance and agreement rate between an abbreviated MRI protocol (aMRI) and a full MRI protocol (fMRI) for detecting pelvic endometriosis. We retrospectively analyzed 446 consecutive MRI exams, including both full (fMRI) and abbreviated (aMRI) protocols, performed for suspected pelvic endometriosis. An expert radiologist assessed the presence of endometriosis at 14 distinct anatomical sites. Each MRI protocol was interpreted in random order, with a minimum two-week interval between sessions to minimize recall bias. Agreement between the protocols was evaluated using kappa statistics. The average age of the patients was 34.13 years. The highest incidences of endometriosis were found in the ovaries (88.8%) and the rectouterine pouch (65%). The MRI protocols demonstrated perfect agreement (kappa coefficient = 1) for the ovaries, bladder, uterus, and cesarean section scar. High agreement was also observed in the rectum and uterine ligaments (kappa coefficients of 0.98 and 0.97). Detection of malignant transformation in existing ovarian endometriomas showed substantial concordance with a kappa coefficient of 0.66. An abbreviated non-contrast MRI protocol exhibits diagnostic accuracy comparable to that of a comprehensive protocol in detecting pelvic endometriosis, with similar confidence and reproducibility. This study demonstrates that an abbreviated MRI protocol is as effective as a full protocol in diagnosing pelvic endometriosis, potentially allowing for quicker, cost-effective imaging without compromising diagnostic accuracy.

Enabling AI-Generated Content for Gadolinium-Free Contrast-Enhanced Breast Magnetic Resonance Imaging.

There is increasing interest in utilizing AI-generated content for gadolinium-free contrast-enhanced breast MRI. To develop a generative model for gadolinium-free contrast-enhanced breast MRI and evaluate the diagnostic utility of the generated scans. Retrospective. Two hundred seventy-six women with 304 breast MRI examinations (49 ± 13 years, 243/61 for training/testing). ZOOMit diffusion-weighted imaging (DWI), T1-weighted volumetric interpolated breath-hold examination (T1W VIBE), and axial T2 3D SPACE at 3.0 T. A generative model was developed to generate contrast-enhanced scans using precontrast T1W VIBE and DWI images. The generated and real images were quantitatively compared using the structural similarity index (SSIM), mean absolute error (MAE), and Dice similarity coefficient. Three radiologists with 8, 5, and 5 years of experience independently rated the image quality and lesion visibility on AI-generated and real images within various subgroups using a five-point scale. Four breast radiologists, with 8, 8, 5, and 5 years of experience, independently and blindly interpreted four reading protocols: unenhanced MRI protocol alone and combined with AI-generated scans, abbreviated MRI protocol, and full-MRI protocol. Results were assessed using t-tests and McNemar tests. Using pathology diagnosis as reference standard, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each reading protocol. A P value <0.05 was considered significant. In the test set, the generated images showed similarity to the real images (SSIM: 0.935 ± 0.047 [SD], MAE: 0.015 ± 0.012 [SD], and Dice coefficient: 0.726 ± 0.177 [SD]). No significant difference in lesion visibility was observed between real and AI-generated scans of the mass, non-mass, and benign lesion subgroups. Adding AI-generated scans to the unenhanced MRI protocol slightly improved breast cancer detection (sensitivity: 92.86% vs. 85.71%, NPV: 76.92% vs. 70.00%); achieved non-inferior diagnostic utility compared to the AB-MRI protocol and full-protocol (sensitivity: 92.86%, 95.24%; NPV: 75.00%, 81.82%). AI-generated gadolinium-free contrast-enhanced breast MRI has potential to improve the sensitivity of unenhanced MRI in detecting breast cancer. 4 TECHNICAL EFFICACY: Stage 3.

The diagnostic value of abbreviated MRI protocol in the surveillance of Branch-Duct intraductal papillary mucinous neoplasm

PurposeTo assess the diagnostic value of abbreviated protocol (AP) MRI to detect the degeneration signs in branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) in patients undergoing a routine MRI follow-up. MethodsThis dual-center retrospective study include patients with BD-IPMN diagnosed on initial comprehensive protocol (CP) MRI who underwent routine MRI follow-up. CP included axial and coronal T2-weighted images (T2WI), axial T1-weighted images (T1WI) before and after contrast administration, 3D MR cholangiopancreatography (MRCP) and diffusion-weighted images (DWI). Two APs, eliminating dynamic sequences ± DWI, were extracted from CP. Two radiologists evaluated the APs separately for IPMN degeneration signs according to Fukuoka criteria and compared the results to the follow-up CP. In patients who underwent EUS, imaging findings were correlated with pathological results. Per-patient and per-lesion sensitivity, specificity, PPV, NPV, and accuracy of APs were calculated. Additionally, the acquisition time for different protocols was calculated. ResultsOne hundred-fourteen patients (56.1 % women, median age: 71 years) with 256 lesions were included. Degeneration signs were observed in 24.6 % and 12.1 % per-patient and per-lesion, respectively. Regarding APs, the per patient sensitivity, specificity, PPV, NPV, and accuracy in the detection of the degeneration signs were 100 %, 93.5 %, 83.3 %, 100 %, and 95.1 %, respectively. No additional role for DWI was detected. AP without DWI economized nearly half of CP acquisition time (388 versus 663 s, respectively). ConclusionAP can confidently replace CP for BD-IPMN follow-up with high sensitivity and PPV while offering benefits such as patient comfort, improved MRI accessibility, and reduced dedicated time for image analysis. DWI necessitates special consideration. Clinical Relevance StatementOur data suggest that APs safely detect all degeneration signs of IPMN. While there is an overestimation of mural nodules due to the lack of contrast injection, this occurs in a negligible number of patients.

Can the abbreviated MRI protocol replace the standard full protocol in the detection and characterization of breast non-mass enhancement?

BackgroundBreast MRI full diagnostic protocol (FDP) showed great value in detecting and characterizing non-mass enhancement (NME); however, it is costly and time-consuming. MRI abbreviated protocol (AP) showed comparable accuracy to FDP in various indications but has not been specifically tested in NME. Our study purpose is to assess the accuracy of the AP in the detection and characterization of breast NME in comparison with the FDP and to perform time analysis of the AP.MethodsPatients who demonstrated NME in dynamic contrast-enhanced MRI were included to be assessed using AP and FDP. Image analysis was performed blindly and independently. Firstly, reconstructed images from the pre- and first post-contrast T1WI (first maximum intensity projection and subtraction) were made available as AP. Later, the time/signal intensity curve and remaining images of the FDP were added to the assessment. Both protocols were compared regarding acquisition time, interpretation time, BI-RADS scores and accuracy in the detection and characterization of NME in correlation to histopathology and/or follow-up. Validity statistics, Cohen-Kappa and ROC curve were used.ResultsFifty-nine NME lesions were identified. AP acquisition and interpretation times were significantly shorter than those of the FDP (3.3 vs. 35 min) and (45 “25–75 s” vs. 108 “80–150 s”) (P < 0.001), respectively. There was almost perfect agreement between the two protocols in the BIRADS grading of NME (k = 0.950, P < 0.001). In ROC curve analysis, the FDP was insignificantly more accurate than the AP (84.8% vs. 81.4%, P = 0.144).ConclusionsBreast MRI–AP is comparable to the FDP in the detection and characterization of breast NME with advantageous time saving.

An Abbreviated Non-Contrast MRI Protocol for Osteomyelitis May Reduce the Need for Sedation in Young Children.

Lengthy MRI examinations in young children often requires sedation. When sedation is unavailable, critical imaging may be delayed. Abbreviating the imaging protocol to a few essential sequences may reduce the need for sedation and prevent delays in patient care. We retrospectively evaluated an abbreviated noncontrast MRI protocol to diagnose lower extremity osteomyelitis in the pediatric population. The IRB approved this study. The radiology information system was searched for lower extremity MRI examinations for osteomyelitis in patients <20 years old from August 2020 to August 2021. Three noncontrast sequences (long axis T1 without fat saturation (FS), long axis STIR, and axial T2 with FS) were independently reviewed by 2 pediatric radiologists. The accuracy of the reviewers was compared to the clinical radiology report based on the unabridged contrast-enhanced standard department protocol. The search yielded 80 exams, mean age was 7 years old, 59% (47/80) were male, and 41% (33/80) were female. The accuracies of reviewer A and reviewer B were 95% and 89%, respectively. The reviewer inter-observer agreement for the diagnosis of osteomyelitis was strong (k=0.79). The accuracy of an abbreviated noncontrast MRI protocol to evaluate lower extremity osteomyelitis in children approaches that of the unabridged protocol and has the potential to decrease the need for sedation in young children.

Clinical usefulness of abbreviated mri protocol in breast cancer detection.

The use of breast MRI for screening has increased over the past decade, mostly in women with a high risk of breast cancer. Abbreviated breast MRI (AB-MR) is introduced to make MRI a more accessible screening modality. AB-MR decreases scanning and reporting time and the overall cost of MRI. This study aims to evaluate the diagnostic efficacy of abbreviated MRI protocol in detecting breast cancer in screening and diagnostic populations, using histopathology as the reference standard. This is a single-centre retrospective cross-sectional study of 134 patients with 198 histologically proven breast lesions who underwent full diagnostic protocol contrast-enhanced breast MRI (FDP-MR) at the University Malaya Medical Centre (UMMC) from 1st January 2018 to 31st December 2019. AB-MR was pre-determined and evaluated with regard to the potential to detect and exclude malignancy from 3 readers of varying radiological experiences. The sensitivity of both AB-MR and FDP-MR were compared using the McNemar test, where both protocols' diagnostic performances were assessed via the receiver operating characteristic (ROC) curve. Inter-observer agreement was analysed using Fleiss Kappa. There were 134 patients with 198 lesions. The average age was 50.9 years old (range 27 - 80). A total of 121 (90%) MRIs were performed for diagnostic purposes. Screening accounted for 9.4% of the cases, 55.6% (n=110) lesions were benign, and 44.4% (n=88) were malignant. The commonest benign and malignant lesions were fibrocystic change (27.3%) and invasive ductal carcinoma (78.4%). The mean sensitivity, specificity, positive predictive value, and negative predictive value for AB-MR were 0.96, 0.57, 0.68 and 0.94, respectively. Both AB-MR and FDP-MR showed excellent diagnostic performance with AUC of 0.88 and 0.96, respectively. The general inter-observer agreement of all three readers for AB-MR was substantial (k=0.69), with fair agreement demonstrated between AB-MR and FDP-MR (k=0.36). The study shows no evidence that the diagnostic efficacy of AB-MR is inferior to FDP-MR. AB-MR, with high sensitivity, has proven its capability in cancer detection and exclusion, especially for biologically aggressive cancers.

A three-sequence dynamic contrast enhanced abbreviated MRI protocol to evaluate response to breast cancer neoadjuvant chemotherapy

PurposeTo develop an ABP-MRI to evaluate response to NAC for invasive breast carcinoma. Study typeA single-center, cross-sectional study. SubjectsA consecutive series of 210 women with invasive breast carcinoma who underwent breast MRI after NAC between 2016 and 2020. Field strength/sequence1.5 T / Dynamic contrast-enhanced. AssessmentMRI scans were independently reevaluated, with access to dynamic contrast-enhanced without contrast and to the first, second, and third post-contrast time (ABP-MRI 1–3). Statistical testsThe diagnostic performance of the ABP-MRIs and the Full protocol (FP-MRI) were analyzed. The Wilcoxon non-parametric test (p-value <0.050) was used to compare the capability in measuring the most extensive residual lesion. ResultsThe median age was 47 (24–80) years. ABP-MRI 1 showed higher specificity (84.6%; 77/91) but a higher probability of false-negatives (16.8%) and lower sensitivity (83.2%; 99/119) than ABP-MRI 2,3 and the FP-MRI, which were identical in specificity (81.3%; 74/91), probability of false-negatives (8.4%), and sensitivity (91.6%; 109/119). ABP-MRI 2 showed a mean underestimation of only 0.03 cm in the measurement of the longest axis of the residual lesion (p = 0.008) with an average reduction in the acquisition time of 75%, compared with the FP-MRI. ConclusionABP-MRI 2 showed diagnostic performance equivalent to the FP-MRI with a 75% reduction in the acquisition time.

Diagnostic and Practical Value of Abbreviated Contrast Enhanced Magnetic Resonance Imaging in Breast Cancer Diagnostics.

Although MRI is the most efficient method of detecting breast cancer, its standard protocol is time-consuming and expensive. The objective of this study was to compare the diagnostic accuracy of the modified innovative abbreviated MRI protocol (AMRP) and the standard magnetic resonance protocol (SMRP) when detecting breast cancer. The research involved 477 patients referred for breast MRI due to suspected lesions. They were randomly assigned to the AMRP group (N = 232) or the SMRP group (N = 245). The AMRP comprised one native (contrast-free) and four post-contrast dynamic sequences of T1-weighted volume imaging for breast assessment (VIBRANT) and 3d MIP (maximum intensity projection) lasting for eight minutes. All the patients underwent a core biopsy of their lesions and histopathological analysis. The groups were comparable regarding the pre-screening and post-diagnostic characteristics and were of average (±SD) age at breast cancer diagnosis of 53.6 ± 12.7 years. There was no significant difference between the two protocols in terms of specificity or sensitivity of breast cancer diagnosis. The sensitivity (95% Cis) of the AMRP was 99.05% (96.6-99.9%), and its specificity was 59.09% (36.4-79.3%), whereas the sensitivity of the SMRP was 98.12% (95.3-99.5%) and its specificity was 68.75% (50.0-83.9%). Most of the tumors comprised one solid lesion in one of the breasts (77.3%), followed by multicentric tumors (16%), bilateral tumors (4.3%), and multifocal tumors (1.7%). The average size of tumors was approximately 14 mm (ranging from 3 mm to 72 mm). Our innovative AMR protocol showed comparable specificity and sensitivity for the diagnosis of breast cancer when compared to SMRP, which is the "gold standard" for histopathological diagnosis. This can lead to great savings in terms of the time and cost of imaging and interpretation.

Current Landscape and Future Perspectives of Abbreviated MRI for Hepatocellular Carcinoma Surveillance.

While ultrasound (US) is considered an important tool for hepatocellular carcinoma (HCC) surveillance, it has limited sensitivity for detecting early-stage HCC. Abbreviated MRI (AMRI) has recently gained popularity owing to better sensitivity in its detection of early-stage HCC than US, while also minimizing the time and cost in comparison to complete contrast-enhanced MRI, as AMRI includes only a few essential sequences tailored for detecting HCC. Currently, three AMRI protocols exist, namely gadoxetic acid-enhanced hepatobiliary-phase AMRI, dynamic contrast-enhanced AMRI, and non-enhanced AMRI. In this study, we discussed the rationale and technical details of AMRI techniques for achieving optimal surveillance performance. The strengths, weaknesses, and current issues of each AMRI protocol were also elucidated. Moreover, we scrutinized previously performed AMRI studies regarding clinical and technical factors. Reporting and recall strategies were discussed while considering the differences in AMRI protocols. A risk-stratified approach for the target population should be taken to maximize the benefits of AMRI and the cost-effectiveness should be considered. In the era of multiple HCC surveillance tools, patients need to be fully informed about their choices for better adherence to a surveillance program.

Performance of imaging interpretation, intra- and inter-reader agreement for diagnosis of pelvic endometriosis: comparison between an abbreviated and full MRI protocol.

To compare the performance of imaging interpretation, intra- and inter-reader agreement between an abbreviated (aMRI) and full (fMRI) MRI protocol for diagnosis of pelvic endometriosis. Seventy consecutive fMRI exams performed under suspicion of pelvic endometriosis were selected. Four radiologists (Rd) (1-10 years experience) independently evaluated presence/absence of endometriosis at 9 anatomic sites (AS). The readers evaluated aMRI (coronal T2 TSE volumetric images and axial T1 GRE fat-sat without contrast, extracted from fMRI) and fMRI protocols randomly, with at least 4weeks interval between readings. The degree of confidence for diagnosis at each AS was evaluated with a 1-3 Likert Scale (1: low; 3: high). Intra- and inter-reader agreement between protocols were evaluated by kappa statistics and took reading experience into account. The gold standard for assessing the performance of imaging interpretation (sensitivity, specificity and accuracy) used a consensus reading of two other Rd (> 15 years experience). There was no significant difference in the accuracy of imaging interpretation between the abbreviated (0.83-0.86) and full (0.83-0.87) protocols (p = 0.15). Intra-reader agreement between protocols ranged from substantial to almost perfect (0.74-0.96). A substantial inter-reader agreement was found for both protocols for readers with similar levels of experience (0.67-0.69) and in the global analysis (0.66 for both protocols). No difference was found in terms of degree of confidence between protocols, for all readers. An abbreviated MRI protocol for pelvic endometriosis provided an accuracy of interpretation comparable to that ofa complete protocol, with similar degrees of confidence and reproducibility, regardless the level of experience.

An abbreviated MRI protocol for surveillance of cystic pancreatic lesions.

Cystic pancreatic lesions (CPLs) are common and increasingly encountered in clinical radiology practice. The appropriate imaging surveillance strategy for lower-risk CPLs (branch duct-intraductal papillary mucinous neoplasms and indeterminant small cystic lesions) has been a topic of intense study and debate in recent years. MRI is considered the investigation of choice for initial characterisation and follow-up of CPLs. Follow-up intervals for CPLs vary from 6months to 2years and surveillance may be lifelong or until the patient is no longer considered fit for potential surgical intervention. This creates a significant burden on MRI resources as a standard protocol pancreatic MRI may have an acquisition time of up to 35-50min. However, the necessity of contrast-enhanced sequences and diffusion weighted imaging (DWI) for routine follow-up of CPLs has been questioned in recent years. We reviewed the available evidence to determine whether an abbreviated MRI (A-MRI) protocol may be safely adopted for surveillance of CPLs, as has been implemented in other clinical scenarios. A number of recent retrospective studies have indicated that an A-MRI, omitting contrast-enhanced and DWI, may be used for CPL surveillance without any suspicious features or cases of malignancy being missed. Although small number of cases may need to be recalled for additional MR sequences based on the A-MRI findings, there is still a significant overall timesaving. The best available evidence currently suggests that an A-MRI protocol should be considered for routine surveillance of CPLs. Prospective studies are required to ensure the findings reported in these retrospective case studies are backed up in ongoing clinical practice.

Diagnostic Performance of Simulated Abbreviated MRI for Early-Stage Hepatocellular Carcinoma Screening: A Comparison to Conventional Dynamic Contrast-Enhanced MRI.

PurposeTo compare the per-patient diagnostic performance of simulated abbreviated MRI (AMRI) to that of conventional MRI (CMRI) with full-sequence dynamic gadoxetic acid (GA) enhancement for early-stage hepatocellular carcinoma (HCC) screening in high-risk patients.Materials and MethodsA total of 201 consecutive patients at high-risk for HCC, who underwent 3T liver MRI, were included in this retrospective study. The AMRI protocol comprised T2-weighted imaging, hepatobiliary phase imaging after GA injection, and diffusion-weighted imaging. For each patient, two AMRI and CMRI image sets were independently reviewed by two radiologists. Inter-reader agreement was assessed using Cohen's kappa value. A composite reference standard was used to determine the diagnostic performance of each image set for each reader.ResultsA total of 93 HCCs were detected in 79 patients. The inter-reader agreement was almost perfect for both image sets (κ = 0.839, 0.948). In AMRI, the per-patient sensitivity and negative predictive values (NPV) were 94.9% and 96.4%, respectively. In CMRI, the per-patient sensitivity and NPV were 96.2% and 97.5%, respectively.ConclusionAMRI, using only three sequences, had a comparable diagnostic performance to CMRI in screening early-stage HCC. AMRI could be an alternative HCC screening tool for high-risk HCC patients.

Abbreviated Breast MRI for Screening High-risk Women: Comparison with the Full Clinical Protocol.

To compare cancer detection rate (CDR), patient recall, and interpretation time of a full protocol MRI (fpMRI) to an abbreviated MRI protocol (abMRI) in high-risk women. This retrospective study was approved by the IRB. All sequential high-risk screening MRI examinations performed between January 1, 2013, and December 31, 2016, were included. Breast radiologists reviewed patient history, prior images, and abMRI images and recorded their interpretation. Time for interpretation reflected review of the MRI study but not dictation or report generation. Following a minimum 30-day washout period, radiologists interpreted the fpMRI, with interpretation and timing recorded. Data collected included CDR, interpretation time, and patient recall rate. Statistical analyses utilized were Cohen's kappa coefficient, Student's t-test, and McNemar's test. Included were 334 MRI examinations of 286 women. Interpretation time was 60.7 seconds for the abMRI compared to 99.4 seconds for the fpMRI, with an average difference of 38.7 ± 5.4 seconds per patient (P < 0.0001). Recall rates were comparable: the abMRI recall rate was 82/334 (24.6%) and the fpMRI 81/334 (24.3%). All five cancers included were detected by both protocols with equal recall rate. However, there were more recommendations for biopsy with the fpMRI, although this difference was not statistically significant. The abMRI demonstrated comparable CDR to fpMRI, with shortened interpretation time and similar recall rates. Implementing an abMRI to screen high-risk women reduces imaging and interpretation time, thereby improving cost-effectiveness and the patient experience without reduction in cancer detection.

Abbreviated MRI protocol for colorectal liver metastases: How the radiologist could work in pre surgical setting.

BackgroundMRI is the most reliable imaging modality that allows to assess liver metastases. Our purpose is to compare the per-lesion and per-patient detection rate of gadoxetic acid-(Gd-EOB) enhanced liver MRI and fast MR protocol including Diffusion Weighted Imaging (DWI) and T2-W Fat Suppression sequence in the detection of liver metastasis in pre surgical setting.MethodsOne hundred and eight patients with pathologically proven liver metastases (756 liver metastases) underwent Gd-EOBMRI were enrolled in this study. Three radiologist independently graded the presence of liver lesions on a five-point confidence scale assessed only abbreviated protocol (DWI and sampling perfection with application-optimized contrasts using different flip angle evolution (SPACE) fat suppressed sequence) and after an interval of more than 2 weeks the conventional study (all acquired sequences). Per-lesion and per-patient detection rate of metastases were calculated. Weighted к values were used to evaluate inter-reader agreement of the confidence scale regarding the presence of the lesion.ResultsMRI detected 732 liver metastases. All lesions were identified both by conventional study as by abbreviated protocol. In terms of per-lesion detection rate of liver metastasis, all three readers had higher detection rate both with abbreviated protocol and with standard protocol with Gd-EOB (96.8% [732 of 756] vs. 96.5% [730 of 756] for reader 1; 95.8% [725 of 756] vs. 95.2% [720 of 756] for reader 2; 96.5% [730 of 756] vs. 96.5% [730 of 756] for reader 3). Inter-reader agreement of lesions detection rate between the three radiologists was excellent (k range, 0.86–0.98) both for Gd-EOB MRI and for Fast protocol (k range, 0.89–0.99).ConclusionAbbreviated protocol showed the same detection rate than conventional study in detection of liver metastases.

Should abbreviated breast MRI be compliant with American College of Radiology requirements for MRI accreditation?

ObjectiveTo evaluate non-inferiority and diagnostic performance of an American College of Radiology compliant abbreviated MRI protocol (AB-MRI) compared with standard-of-care breast MRI (SOC-BMRI) in patients with increased breast cancer risk. Material and methodsWomen with increased lifetime breast cancer risk by American Cancer Society guidelines underwent breast MRI at a single institution between October 2015 and February 2018. AB-MRI was acquired at 3.0 T with T2-weighted extended fast spin echo triple-echo Dixon and pre- and post-contrast 3D dual-echo fast spoiled gradient echo two-point Dixon sequences with an 8-channel breast coil 1–7 days after SOC-BMRI. Three readers independently reviewed AB-MRI and assigned BI-RADS categories for maximum intensity projection images (AB1), dynamic contrast-enhanced (DCE) images (AB2), and DCE and non-contrast T2 and fat-only images (AB3). These scores were compared to those from SOC-BMRI. ResultsCancer yield was 14 per 1000 (women-years) in 73 women aged 26–75 years (mean 53.5 years). AB-MRI acquisition times (mean 9.63 min) and table times (mean 15.07 min) were significantly shorter than those of SOC-BMRI (means 19.46 and 36.3 min, respectively) (p < .001). Accuracy, sensitivity, specificity, and positive and negative predictive values were identical for AB3 and SOC-BMRI (93%, 100%, 93%, 16.7%, and 100%, respectively). AB-MRI with AB1 and AB2 had significantly lower specificity (AB1 = 73.6%, AB2 = 77.8%), positive predictive values (AB1 = 5%, AB2 = 5.9%), and accuracy (AB1 = 74%, AB2 = 78%) than those of SOC-BMRI (p = .002 for AB1, p = .01 for AB2). ConclusionAB-MRI was acquired significantly faster than SOC-BMRI and its diagnostic performance was non-inferior. Inclusion of T2 and fat-only images was necessary to achieve non-inferiority by multireader evaluation.

Pancreatic Neuroendocrine Tumors in Patients with Multiple Endocrine Neoplasia Type 1: Diagnostic Value of Different MRI Sequences

Background: MRI is a useful imaging modality to assess the presence of pancreatic neuroendocrine tumors (PNETs), allowing repeat monitoring examinations in multiple endocrine neoplasia type 1 (MEN-1) patients. Objectives: We aimed to compare the diagnostic accuracy of conventional MRI sequences to identify which sequence better depicts the presence of PNETs in MEN-1 patients. Method: We performed a retrospective analysis of consecutive MEN-1 patients who underwent a conventional MRI protocol to monitor previously proven PNETs. MRI sequences T1-w chemical shift (CS), T2-w HASTE, fat-suppressed (FS) T2-w HASTE, diffusion-weighted imaging (DWI), and pre- and post-contrast FS T1-w sequences were independently analyzed by 2 experienced radiologists using a 3-grade score (no lesion, uncertain lesion, and certain lesion); lesion size and signal intensity were recorded. A Friedman ANOVA and a Wilcoxon pairwise test for the post hoc analysis were used. The sensitivity of each sequence was measured, and the results were analyzed with the χ² test. Results: We included 21 patients with a total of 45 PNETs proven by histology, endoscopic ultrasonography-guided fine-needle aspiration, CT, and nuclear medicine studies. A statistically significant (p < 0.01) difference was observed in the detection performance of each MRI sequence, particularly between DWI (91%) and T2-w FS (85%) sequences in comparison to the others (T1-w CS, T2-w, and pre- and post-contrast FS T1-w, ≤56% for all); no significant (p = 0.5) difference was found between the detection performance of DWI and T2-w FS sequences. No correlation was observed between the qualitative score of each sequence and lesion tumor size. Conclusions: DWI and T2-w FS sequences proved to be the most accurate in the detection of PNETs, thus suggesting a role for an abbreviated MRI protocol without contrast medium administration for monitoring MEN-1 patients.

Role of abbreviated MRI protocol for screening of HCC in HCV related cirrhotic patients prior to direct-acting antiviral treatment

BackgroundChronic HCV infection is a global health problem causing progressive hepatic fibrosis, cirrhosis, and ultimately hepatocellular carcinoma (HCC). Recent advantage of direct-acting antiviral drugs (DAA) with a high sustained virologic response (SVR) reduces overall HCV-related morbidity and mortality, yet recent studies report a high recurrence rate of HCC after DAA; this calls availability of a reliable screening method to properly exclude HCC before DAA treatment.The primary objective of our cohort study was to assess the feasibility of an abbreviated MRI protocol as a screening tool for the detection of hepatic focal lesions/early HCC in patients with HCV-related liver cirrhosis.The study included 41 patients with HCV-related cirrhosis candidates to DAA therapy. All patients underwent routine screening for HCC by combined abdominal ultrasound and serum alfa-fetoprotein. An abbreviated MRI protocol (Abr-MR) including combined T2-weighted image and diffusion-weighted imaging (DWI) followed by dynamic contrast-enhanced MRI (CE-MRI) was performed for all subjects, assessing for presence and characterization of focal lesions.ResultsFor all included 41patients, no elevation of the alpha-fetoprotein was shown. Ultrasound detected a single focal lesion in one patient. Abbreviated MR demonstrated 15 focal lesions; for detected lesions, 1 lesion shows “shine though” and the rest showing moderate and high degrees of restriction. CE-MRI characterized lesions as 1 lesion = LIRADS-1, 3 lesions = LR-M, and 11 lesions = LR-5.The standard screening using combined ultrasound and alpha-fetoprotein had sensitivity, specificity, PPV, and NPV of 6.6 % (95% CI = 0.0034–0.29), 100% (95% CI = 0.89–1.000), 100% (95% CI = 0.051–1.000), and 68.8% (95% CI = 0.54–0.80). Abr-MR protocol showed sensitivity, specificity, PPV, and NPV of 100% for all parameters (95% CI = 0.79–1.000, 0.89–1.000, 0.79–1.000, and 0.89–1.000 respectively).ConclusionIn our study, we demonstrate the superiority of a proposed cost-effective Abr-MR protocol in the detection of hepatic focal lesions and small-sized HCC compared to routine screening using alpha-fetoprotein and ultrasound in HCV-related liver cirrhosis.

An Abbreviated MRI Protocol for Breast Cancer Screening in Women With Dense Breasts

An Abbreviated MRI Protocol for Breast Cancer Screening in Women With Dense Breasts

Potential role of abbreviated MRI for breast cancer screening in an academic medical center.

The purpose is to determine whether an abbreviated MRI protocol (ABMR) is ready to be used for breast cancer screening in an academic practice setting. Two hundred and fifty nine breast MRIs from 1/1/2012 to 6/30/2012 were retrospectively reviewed using ABMR (MIP, Pre-contrastT1, single dynamic post-contrastT1, and subtraction). Five breast radiologists (4-28year-expr) participated in this reader study performed in two phases: Phase1 - radiologist's privy to clinical history but not to comparison imaging. Phase2 - radiologists provided comparison imaging. For phase1, studies were reviewed using three steps: (a) MIP only (positive/negative/intermediate); (b) ABMR (recall/no recall) and (c) With T2 (for changes in recommendations). Radiologist also recorded total time for interpretation. In Phase2 the MRIs coded as "recall" were re-reviewed with available comparison studies, noting changes in final recommendation. The abnormal interpretation rates (AIRs) were calculated for phase1 and phase2 results with comparison to the original full protocol. Of the 259 patients (avg. age-52years; range 26-78), there were seven cancers (three invasive, three DCIS and one breast lymphoma). Acquisition time for ABMR was 3minutes, ABMR+T2-8minutes, and original full protocol 16minutes. Average MIP was positive or indeterminate in 86% (6/7) and negative in 14% (1/7) cancers. The average AIR for MIP only was 20.8% (sens-77.1%; spec-80.8%. The AIR w/o comparisons was 25.6% (sens-91.4%; spec- 76.2%); however the average AIR decreased in phase 2 with comparisons to 13.7% (sens-91.4%; spec-88.5%). The AIR of the original full protocol read was 16.2% (sens-100%; spec-85.7%). Addition of T2 changed assessment in only 3% (1.2%-6.5%). Avg. read time for ABMR including T2 was 2.5minutes (1.6-4.0minutes). ABMR is reliable for breast cancer screening, with acceptable interpretation time and acceptable AIR.

Lesion detection performance of an abbreviated gadoxetic acid-enhanced MRI protocol for colorectal liver metastasis surveillance.

To assess the lesion detection performance of an abbreviated MRI (AMRI-M) protocol consisting of ultrafast SE T2W, DWI, and T1W-HBP at 20min for colorectal liver metastasis (CRLM) surveillance. In this Institutional Review Board (IRB)-approved retrospective study, gadoxetic acid-enhanced MRI scans of 57 patients (43 with pathologically proven CRLMs) were assessed. Two readers independently evaluated two sets of images per patient and commented on the number, location, and size of liver lesions. Set 1 included ultrafast spin-echo (SE) T2-weighted (T2W) + T1-weighted (T1W) hepatobiliary phase (HBP) at 20min sequences + diffusion-weighted imaging (DWI), and set 2 consisted of the standard MRI protocol. A maximum of 10 lesions per patient were recorded. Cohen's kappa analysis, sensitivity, areas under the curve (AUCs), and the MRI cost analysis of the AMRI-M protocol were assessed. Between 198 and 209 lesions were assessed with each set of images. The inter-observer agreement for the abbreviated protocol was reported excellent (κ = 0.91). The sensitivity and AUCs for the lesion characterization of AMRI-M protocol were very high (over 90%) for both readers. No statistically significant differences in sensitivity (assessed by mixed-effects logistic regression) and AUCs for lesion characterization (by ROC regression) were found between both protocols. The AMRI-M acquisition time was estimated to be less than 10min, which translated into 59% cost of standard MRI. Our proposed AMRI-M protocol (ultrafast SE T2W, DWI, and T1W-HBP at 20min) is fast, low-cost alternative to the standard MRI protocol and has a high lesion detection performance. • Gadoxetic acid-enhanced protocol has increased the accuracy, sensitivity, and specificity of MRI for detecting colorectal liver metastases. • Our proposed abbreviated MRI protocol is fast, low-cost alternative compared with the standard MRI protocol and has a high lesion detection performance. • Adoption of our protocol may translate to substantial savings for patients and payers.