Complete MRI Research Articles

Multicenter validation of synthetic FLAIR as a substitute for FLAIR sequence in acute ischemic stroke.

To evaluate performance of synthetic and real FLAIR for identifying early stroke in a multicenter cohort. This retrospective study was conducted using DWI and FLAIR extracted from the Endovascular Treatment in Ischemic Stroke image registry (2017-2021). The database was partitioned into subsets according to MRI field strength and manufacturer, and randomly divided into training set (70%) used for model fine-tuning, validation set (15%), and test set (15%). In test set, five readers, blinded to FLAIR sequence type, assessed DWI-FLAIR mismatch using real and synthetic FLAIR. Interobserver agreement for DWI-FLAIR rating and concordance between synthetic and real FLAIR were evaluated with kappa statistics. Sensitivity and specificity for identification of ⩽4.5 h AIS were compared in patients with known onset-to-MRI delay using McNemar's test. 1454 complete MRI sets (1172 patients, median (IQR) age: 73 years (62-82); 762 women) acquired on 125 MRI units were analyzed. In test set (207 MRI), interobserver reproducibility for DWI-FLAIR mismatch labeling was substantial for real and synthetic FLAIR (Fleiss κ = 0.79 (95%CI: 0.73-0.84) and 0.77 (95%CI: 0.71-0.82), respectively). After consensus, concordance between real and synthetic FLAIR was excellent (κ = 0.85 (95%CI: 0.78-0.92)). In 141 MRI sets with known onset-to-MRI delay, diagnostic performances for ⩽4.5 h AIS identification did not differ between real and synthetic FLAIR (sensitivity: 60/71 (85%) vs 59/71 (83%), p = .56; specificity: 65/70 (93%) vs 65/70 (93%), p > 0.99). A deep-learning-based FLAIR fine-tuned on multicenter data can provide comparable performances to real FLAIR for early AIS identification. This approach may help reducing MR protocol duration and motion artifacts.

Validation of the 2023 International Diagnostic Criteria for MOGAD in a Selected Cohort of Adults and Children.

To test the performance of the 2023 myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) criteria in adults and children with inflammatory demyelinating conditions who were tested for MOG antibodies (Abs). This was a retrospective study of patients tested for MOG-Abs from 2018 to 2022 in 2 specialist hospitals. The inclusion criteria comprised ≥1 attendance in an adult or pediatric demyelinating disease clinic and complete clinical and MRI records. The final clinical diagnosis of MOGAD, made by the treating neurologist, was taken as the benchmark against which the new criteria were tested. The international MOGAD diagnostic criteria were applied retrospectively; they stipulate at least 1 clinical or MRI supporting feature for MOGAD diagnosis in positive fixed MOG cell-based assay without a titer. The performance MOG-Ab testing alone for MOGAD diagnosis was also assessed and compared with that of MOGAD criteria using the McNemar test. Of the 1,879 patients tested for MOG-Abs, 539 (135 pediatric and 404 adults) met the inclusion criteria. A clinical diagnosis of MOGAD was made in 86/539 (16%) patients (37 adults, 49 children), with a median follow-up of 3.6 years. The MOGAD diagnostic criteria had sensitivity of 96.5% (adults 91.9%, children 100%), specificity of 98.9% (adults 98.8%, children 98.9%), positive predictive value of 94.3% (adults 89.4%, children 98%), negative predictive value of 99.3% (adults 99.2%, children 100%), and accuracy of 98.5% (adults 98.3%, children 99.2%). When compared with MOG-Ab testing alone, a difference was seen only in adults: a significantly higher specificity (98.9% vs 95.6%, p = 0.0005) and nonstatistically significant lower sensitivity (91.9% vs 100%, p = 0.08). The international MOGAD diagnostic criteria exhibit high performance in selected patients with inflammatory demyelinating diseases (who had a high pretest probability of having MOGAD) compared with best clinical judgment; their performance was better in children than in adults. In adults, the MOGAD criteria led to an improvement in specificity and positive predictive value when compared with MOG-Ab testing alone, suggesting that the requirement of at least 1 clinical or MRI supporting feature is important. Future work should address the generalizability of the diagnostic criteria to cohorts of greater clinical diversity seen within neurologic settings.

Assessment of visuospatial functions in post-Covid 19 patients: Beyond the traditional paradigm

Several studies indicate that some cognitive changes occur after COVID-19. Visuospatial alterations have been reported in 24–40 %. These alterations may be useful as early biomarkers of neurodegenerative disease. Thus, we can emphasize the importance of visuospatial processes in cognition through quantitative and qualitative analysis of performance on the Clock Test (CDT) and the Rey-Osterrieth Complex Figure (FCRO). Our objective was to describe the performance of post COVID 19 patients in visuospatial tests, with different degrees of respiratory impairment and to perform a qualitative analysis of the performance to check its relationship with alterations in attention and executive functions. This will allow highlighting the executive component of the performance of the CDT and ROCF and differentiate patients with possible cognitive impairment. 77 patients with SARS-CoV-2 infection were evaluated (3 months post-infection) with a complete neuropsychological battery and MRI. Overall, there is a significant difference between FCRO and CDT, with FCRO having only 9 % change and CDT having 51.9 % change. Regarding the correlations observed between groups (VM Inv, VM non I and non hospitalized) the highest correlations were observed between Boston with FCRO copy (r=0.497; p=0.001) and with FCRO memory (r=0.429; p=0.001). Comparing the performance between groups by severity, significant differences were observed only in the TMT A (13.706 p=0.001) and B (9.583 p=0.008) tests and in the phonological fluency letter A (13.445 p=0.001), we observed that the group of non-hospitalized patients had a better performance. Neuropsychological deficits often have a direct impact on daily life by affecting the ability to learn and adapt. Thus, a useful strategy for the neuropsychological characterization of post-COVID-19 patients is the qualitative analysis of visuospatial abilities in conjunction with executive functions that cannot be analyzed in isolation.

NeoTRACT: Phase II trial of neoadjuvant tumor infiltrating lymphocyte- and response-adapted chemoimmunotherapy for triple-negative breast cancer (TNBC).

TPS629 Background: Neoadjuvant chemoimmunotherapy is recommended for patients with high risk early stage TNBC. The 5 drug KEYNOTE-522 neoadjuvant chemoimmunotherapy regimen involves 5-6 months of treatment and is associated with suboptimal treatment completion due to toxicity. Approaches to deescalate chemoimmunotherapy without compromising outcomes for patients with highly chemosensitive disease are needed. Stromal tumor infiltrating lymphocyte (sTIL) enrichment is positively associated with pathologic complete response (pCR) in TNBC and may be useful to identify patients for whom de-escalation of neoadjuvant chemoimmunotherapy might be acceptable. NeoTRACT trial investigates deescalating neoadjuvant chemoimmunotherapy based on degree of pretreatment sTIL enrichment. We hypothesize that baseline immune upregulation assessed by sTILs can guide neoadjuvant treatment optimization in TNBC patients. Specifically, in patients with immune enriched TNBC (sTILs ≥30%), short anthracycline free taxane–platinum chemoimmunotherapy will yield high pCR rate. Methods: NeoTRACT is an ongoing open label phase II trial for patients with previously untreated TNM stage I (T>1cm)–III TNBC. TNBC is defined as estrogen and progesterone receptor ≤10% and HER2 negative per ASCO/CAP criteria. Patients with T4 or N3 breast cancer are excluded. Patients must have adequate organ function and no contraindication to pembrolizumab. All participants initiate carboplatin (AUC 6) + docetaxel (75mg/m2) + pembrolizumab (200mg) (CbD+P) every 21 days. After registration, sTILs are evaluated centrally on pretreatment H&E core needle biopsy slide using standard criteria. Participants are assigned to three neoadjuvant treatment regimens (A, B, or C) based on sTIL enrichment. Regimen A (sTILs ≥30%) includes four cycles CbD+P. All participants assigned to regimen A undergo breast MRI after four cycles: those with complete MRI response proceed to breast surgery; those with less than complete MRI response receive two additional cycles of CbD+P. Regimen B (sTILs 5-29%) includes six cycles of CbD+P. Regimen C (sTILs <5%) includes four cycles of CbD+P followed by four cycles of doxorubicin (60mg/m2) + cyclophosphamide (600mg/m2) + P (200mg) (AC+P). All patients undergo surgery after completing the assigned neoadjuvant regimen. Breast/axillary surgery, adjuvant systemic therapy, and radiotherapy are recommended per standard of care. pCR is defined as absence of residual invasive disease in breast and axilla. Primary endpoint is pCR rate among participants with ≥30% sTILs. Secondary endpoints include residual cancer burden (RCB) rates in patients with ≥30% sTILs, pCR and RCB rates in patients with 5-29% and <5% sTILs, and event free and overall survival for all patients. As of January 2024, 45 of 139 participants have been enrolled. Clinical trial information: NCT05645380 .

Post-operative MRI synthesis from pre-operative MRI and post-operative CT using conditional GAN for the assessment of degree of resection

BackgroundMagnetic resonance imaging (MRI) is an essential part of assessing the extension of resection after craniotomy, allowing for accurate assessment of the brain. However, the application of MRI within 72 h after surgery is limited, owing to its high cost, long time duration, and patients’ limited mobility. Besides, MRI excludes people with contraindications, in which sceneries computerized tomography (CT) is the only available choice. To overcome these limitations, we investigated the use of a deep learning model for synthesizing post-operative MRI images. MethodsWe employed Cross-domain Correspondence Learning for Exemplar-based Image Translation Network (CoCosNet), an exemplar-based image translation model to synthesize T1 contrast-enhanced (T1ce) MRI images by combining post-operative T1ce and post-operative CT images. 233 cases were retrospectively collected at Sun Yat-sen University Cancer Center and underwent complete MRI and CT scans. ResultsAfter 200 epochs and a batch size of 10, CoCosNet achieved comparable results compared to other existing models, with objective indicators structural similarity index = 0.75, peak signal to noise ratio = 21.68, and mean absolute error = 0.007. Furthermore, assessments of the extension of resection between the true and synthesized T1ce images achieve great consistency. ConclusionsOur study demonstrates the effectiveness of the CoCosNet model in synthesizing post-operative MRI images from pre-operative MRI and post-operative CT scans. Quantitative analysis indicates that the synthesized images have comparable quality to real MRI images and can accurately discriminate the extent of resection. This approach has a promising future by providing a reliable alternative to traditional post-operative MRI.

Abstract PO3-07-06: Correlation between residual microcalcification and in-breast pathologic response in relation to MRI response and the subtypes after neoadjuvant chemotherapy

Abstract Background The significance of residual microcalcifications after neoadjuvant chemotherapy (NAC) in determining the extent of surgical intervention in breast cancer remains unclear. This study aimed to assess whether residual microcalcifications after NAC correlate with the residual disease in patients with breast cancer stratified by subtypes, particularly in excellent radiologic responders. Methods We conducted a retrospective study of patients with breast cancer who underwent NAC followed by curative surgery between January 2007 and December 2022. We evaluated the presence of suspicious microcalcifications on pre-NAC mammography and residual microcalcifications on post-NAC mammography. In the patients who had residual microcalcifications on post-NAC mammography, the rates of breast pathologic complete response (pCR), defined as the absence of invasive cancer (ypT0/is) or complete breast pCR defined as the absence of invasive cancer and in-situ cancer in the breast (ypT0), was assessed according to the MRI response and subtypes. We defined complete MRI response as the resolution of suspicious enhancement in the breast and axilla after NAC. Results Of the 1078 patients, 554 (51.4%) had suspicious microcalcifications at baseline, of which 518 (93.5%) had residual microcalcifications after NAC. Among the 518 patients with residual microcalcifications, 93 (18.0%) achieved a complete MRI response. We observed a difference in breast pCR rates depending on MRI response and hormone-receptor (HR) status. In the patients without complete MRI response, about one-third of patients (139 of 425 [32.7%]) achieved a breast pCR, irrespective of HR status (19.3% [47 of 244] in HR-positive breast cancer and 50.8% [92 of 181] in HR- negative breast cancer). Of the 93 patients who achieved a complete MRI response, the breast pCR rates were 64.3% (27 of 42) in HR-positive breast cancer and 96.1% (49 of 51) in HR-negative breast cancer, respectively. Moreover, the breast complete pCR rate was 54.8% (23 of 51) in HR-positive breast cancer and 88.2% (45 of 51) in HR-negative breast cancer, including 87.2% (34 of 39) in HR-HER2+ breast cancer and 91.7% (11 of 12) in triple-negative breast cancer. Conclusion Our results suggest that the clinical relevance of the residual microcalcifications differs according to the breast cancer subtypes. For patients with HR-positive breast cancer, removal of the residual microcalcifications should be considered to ensure complete cancer removal, regardless of MRI response. In contrast, de-escalating surgery may be considered in patients with HR-negative breast cancer who achieve complete MRI response after NAC. Citation Format: Soong June Bae, Seung Ho Baek, Seung Eun Lee, Min Ji Kim, Sohyun Moon, Junghyun Kim, Yoonwon Kook, Joon Jeong, Sung Gwe Ahn. Correlation between residual microcalcification and in-breast pathologic response in relation to MRI response and the subtypes after neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-07-06.

Outcomes of sentinel node biopsy according to MRI response in an association with the subtypes in cN1–3 breast cancer after neoadjuvant systemic therapy, multicenter cohort study

BackgroundThis study investigated the feasibility of sentinel lymph node biopsy (SLNB) after neoadjuvant systemic therapy (NAST) in patients with initially high nodal burden.MethodsIn the multicenter retrospective cohort, 388 individuals with cN1–3 breast cancer who underwent NAST and had SLNB followed by completion axillary lymph node dissection were included. In an external validation cohort, 267 patients with HER2+ or triple-negative breast cancer (TNBC) meeting similar inclusion criteria were included. Primary outcome was the false-negative rates (FNRs) of SLNB according to the MRI response and subtypes. We defined complete MRI responders as patients who experienced disappearance of suspicious features in the breast and axilla after NAST.ResultsIn the multicenter retrospective cohort, 130 (33.5%) of 388 patients were of cN2-3, and 55 (14.2%) of 388 patients showed complete MRI responses. In hormone receptor-positive HER2− (n = 207), complete and non-complete responders had a high FNRs (31.3% [95% CI 8.6–54.0] and 20.9% [95% CI 14.1–27.6], respectively). However, in HER2+ or TNBC (n = 181), the FNR of complete MRI responders was 0% (95% CI 0–0), whereas that of non-complete responders was 33.3% (95% CI 20.8–45.9). When we validated our findings in the external cohort with HER2+ or TNBC (n = 267), of which 34.2% were cN2-3, the FNRs of complete were 7.1% (95% CI 0–16.7).ConclusionsOur findings suggest that SLNB can be a reliable option for nodal status evaluation in selected patients who have responded well to NAST, especially in HER2+ and TNBC patients who show a complete MRI response.

Five-minute knee MRI: An AI-based super resolution reconstruction approach for compressed sensing. A validation study on healthy volunteers

PurposeTo investigate the potential of combining Compressed Sensing (CS) and a newly developed AI-based super resolution reconstruction prototype consisting of a series of convolutional neural networks (CNN) for a complete five-minute 2D knee MRI protocol. MethodsIn this prospective study, 20 volunteers were examined using a 3T-MRI-scanner (Ingenia Elition X, Philips). Similar to clinical practice, the protocol consists of a fat-saturated 2D-proton-density-sequence in coronal, sagittal and transversal orientation as well as a sagittal T1-weighted sequence. The sequences were acquired with two different resolutions (standard and low resolution) and the raw data reconstructed with two different reconstruction algorithms: a conventional Compressed SENSE (CS) and a new CNN-based algorithm for denoising and subsequently to interpolate and therewith increase the sharpness of the image (CS-SuperRes). Subjective image quality was evaluated by two blinded radiologists reviewing 8 criteria on a 5-point Likert scale and signal-to-noise ratio calculated as an objective parameter. ResultsThe protocol reconstructed with CS-SuperRes received higher ratings than the time-equivalent CS reconstructions, statistically significant especially for low resolution acquisitions (e.g., overall image impression: 4.3 ± 0.4 vs. 3.4 ± 0.4, p < 0.05). CS-SuperRes reconstructions for the low resolution acquisition were comparable to traditional CS reconstructions with standard resolution for all parameters, achieving a scan time reduction from 11:01 min to 4:46 min (57 %) for the complete protocol (e.g. overall image impression: 4.3 ± 0.4 vs. 4.0 ± 0.5, p < 0.05). ConclusionThe newly-developed AI-based reconstruction algorithm CS-SuperRes allows to reduce scan time by 57% while maintaining unchanged image quality compared to the conventional CS reconstruction.

Optic Neuropathy AFG3L2 Related in a Patient Affected by Congenital Stationary Night Blindness

Objective: We describe a patient affected by congenital stationary night blindness (CSNB) secondary to CACNA1F and optic neuropathy associated with an AFG3L2 variant.Methods: We performed comprehensive neuro‐ophthalmologic examinations, retinal imaging, complete ocular electrophysiology, and brain and optic nerve MRI. Genomic DNA was extracted from the peripheral blood. The patient’s DNA was then investigated by next‐generation sequencing (NGS) with a panel including 32 genes associated with retinal dystrophy and therefore with a panel including seven genes associated with genetic forms of optic atrophy.Results: The genetic analysis identified a pathogenetic CACNA1F variant causing CSNB and a heterozygous variant in AFG3L2 that alters OPA1 processing and is known to be associated with OPA1‐like optic neuropathy.Conclusion: Optic disc atrophy has been previously described as an atypical feature in the phenotype of CSNB CACNA1F‐related. In this patient, we found a variant of the AFG3L2 gene that presumably explains the presence of optic atrophy in a subject affected by CSNB.Clinical Relevance: The clinical evidence of optic atrophy, which is atypical in CSNB, should raise the suspicion of concomitant hereditary optic neuropathy and emphasize the importance of broad genetic diagnostic testing to better define the genotype–phenotype correlation.

Patterns of ankle injury in soccer: MRI clues to traumatic mechanism.

Understanding the traumatic mechanisms of ankle injuries in soccer is crucial for an accurate and complete MRI diagnosis. Many ankle injuries share universal mechanisms seen in other athletic activities, but certain patterns are found to be more specific and relatively unique to soccer. Ankle impingement syndromes encountered in soccer encompass a spectrum of disorders that include anterior and posterior impingement categories, with anterior impingement representing pathology relatively specific to soccer. Lateral ligamentous sprains are one of the most common injuries; however, there is a higher rate of injuries to the medial structures in soccer as compared to other sports. Ankle fractures are uncommon in soccer while bone contusions and chondral and osteochondral injuries frequently accompany ligamentous sprains. Tendon abnormalities in soccer most commonly result from overuse injuries and typically affect peroneal tendons, posterior and anterior tibialis tendons, and Achilles tendon. Acute Achilles tendon ruptures occur in both recreational players and elite soccer athletes. Tibialis anterior friction syndrome may mimic tibial stress fractures. Long-term sequelae of acute traumatic and chronic overuse ankle injuries in professional soccer players manifest as ankle osteoarthritis that is more prevalent compared to not only the general population, but also to former elite athletes from other sports. This article examines the most common and specific injuries in soccer in order of their frequency.

Incidental findings and safety events from magnetic resonance imaging simulation for head and neck radiation treatment planning: A single institution experience

PurposeHaving dedicated MRI scanners within radiation oncology departments may present unexpected challenges since radiation oncologists and radiation therapists are generally not trained in this modality and there are potential patient safety concerns. This study retrospectively reviews the incidental findings and safety events that were observed at a single institution during introduction of MRI sim for head and neck radiotherapy planning. MethodsConsecutive patients from March 1, 2020, to May 31, 2022, who were scheduled for MRI sim after having completed CT simulation for head and neck radiotherapy were included for analysis. Patients first underwent a CT simulation with a thermoplastic mask and in most cases with an intraoral stent. The same setup was then reproduced in the MRI simulator. Safety events were instances where scheduled MRI sims were not completed due to the MRI technologist identifying MRI-incompatible devices or objects at the time of sim. Incidental findings were identified during weekly quality assurance rounds as a joint enterprise of head and neck radiation oncology and neuroradiology. Categorical variables between completed and not completed MRI sims were compared using the Chi-Square test and continuous variables were compared using the Mann-Whitney U test with a p-value of < 0.05 considered to be statistically significant. Results148 of 169 MRI sims (88 %) were completed as scheduled and 21 (12 %) were not completed (Table 1). Among the 21 aborted MRI sims, the most common reason was due to safety events flagged by the MRI technologist (n = 8, 38 %) because of the presence of metal or a medical device that was not noted at the time of initial screening by the administrative coordinator. Patients who did not complete MRI sim were more likely to be treated for non-squamous head and neck primary tumor (p = 0.016) and were being treated post-operatively (p < 0.001). CT and MRI sim scans each had 17 incidental findings. CT simulation detected 3 cases of new metastases in lungs, which were outside the scan parameters of MRI sim. MRI sim detected one case of dural venous thrombosis and one case of cervical spine epidural abscess, which were not detected by CT simulation. ConclusionsRadiation oncology departments with dedicated MRI simulation scanners would benefit from diagnostic radiology review for incidental findings and having therapists with MRI safety credentialing to catch near-miss events.

In vivo MRI assessment of locus coeruleus and nucleus basalis of Meynert integrity in frontotemporal degeneration and corticobasal syndrome.

AbstractBackgroundNeuropathological studies have shown alterations in both locus coeruleus (LC) and basal forebrain in frontotemporal degeneration (FTD) and corticobasal syndrome (CBS) particularly in progressive supranuclear palsy (PSP). We aimed to investigate in vivo the LC and nucleus basalis of Meynert (NBM) integrity in patients with FTD and CBS.MethodWe compared the LC signal intensity (LC‐I), which reflects the LC integrity, and the NBM volume on 3T MRI in i) FTD patients (n = 17) ii) CBS patients (n = 8;) iii) prodromal/mild AD (n = 34) and iv) amyloid‐negative controls (n = 15). PiB‐PET and/or AD CSF biomarkers were negative in all FTD and CBS patients, and positive in all AD patients. All subjects underwent a complete neuropsychological assessment and 3T brain MRI performed on the same scan. The four groups were age‐matched. The MMSE score did not differ significantly between the 3 groups of patients.ResultCompared to controls, LC‐I and NBM volume were significantly decreased in FTD (p = 0.05 and 0.00015, respectively) and AD patients (p = 0.0005 and 0.002, respectively). LC‐I and NBM volume were also decreased in CBS in comparison with controls but the difference was not statistically significant. In addition, we found no statistically significant difference in LC‐I and NBM volume between the three groups of patients. We observed no correlation between LC‐I or NBM volume and amyloid load, either when considering the whole group of patients or AD and FTD/CBS patients separately.ConclusionOur results are in line with neuropathological data and suggest that both cholinergic and noradrenergic systems are altered in AD and FTD. Post mortem data have suggested that, in FTD, both structures were more impaired in tau than in TDP‐43 proteinopathy, which cannot be explored in our study. In CBS, our results are less clear‐cut, probably due to the small sample size. Taken together, our data support the pathophysiological model in which both LC and NBM play a critical role not only in AD but also in other diseases and proteinopathies like FTD.

Alzheimer’s disease clinical management is determined by presence and severity of apathy

AbstractBackgroundApathy and agitation influence daily life and care in dementia. We believe it may also influence the diagnosis, especially in early stages. We intend to examine apathy among the symptoms and the relationship with the referral schedule and early diagnosis.MethodOutpatients referred for possible cognitive impairment included in a database of “apathy and cognitive impairment”. Clinical history, complete neuropsychological battery, MRI, MRI, laboratory, and treatment. In addition, some patients also undergo EEG, CSF and/or amyloid PET scans. Neuropsychological battery with special attention to the assessment of apathy and behavioral symptoms. Additionally, semi‐structured rating of the severity of apathy when patients were referred for the first time.Result64 finally diagnosed as Alzheimer’s disease (CDR 0.5 to 2). Group differences according to the frequency and severity of apathy. Those who showed apathy or depression (Independently) as a predominant symptom when referred were more often treated with psychopharmacological therapy by Primary Physician or referred to Psychiatry, where AD was generally less considered. The level of apathy showed negative correlations with MMSE, for the same group (CDR) of patients. Significantly higher levels of apathy higher levels of apathy associated with intake of antidepressants and cognitive enhancers.ConclusionWe observed different patterns of apathy in outpatients with MCI and patients with dementia; significant negative effect on early neurological assessment of those patients, and therefore deleterious effect on their opportunities for a correct approach in the early stages of the disease.

Comparative Performance of 2018 LI-RADS versus Modified LIRADS (mLI-RADS): An Individual Participant Data Meta-Analysis.

LI-RADS version 2018 (v2018) is used for non-invasive diagnosis of hepatocellular carcinoma (HCC). A recently proposed modification (known as mLI-RADS) demonstrated improved sensitivity while maintaining specificity and positive predictive value (PPV) of LI-RADS category 5 (definite HCC) for HCC. However, mLI-RADS requires multicenter validation. To evaluate the performance of v2018 and mLI-RADS for liver lesions in a large, heterogeneous, multi-national cohort of patients at risk for HCC. Systematic review and meta-analysis using individual participant data (IPD) [Study Protocol: https://osf.io/duys4]. 2223 observations from 1817 patients (includes all LI-RADS categories; females = 448, males = 1361, not reported = 8) at elevated risk for developing HCC (based on LI-RADS population criteria) from 12 retrospective studies. 1.5T and 3T; complete liver MRI with gadoxetate disodium, including axial T2w images and dynamic axial fat-suppressed T1w images precontrast and in the arterial, portal venous, transitional, and hepatobiliary phases. Diffusion-weighted imaging was used when available. Liver observations were categorized using v2018 and mLI-RADS. The diagnostic performance of each system's category 5 (LR-5 and mLR-5) for HCC were compared. The Quality Assessment of Diagnostic Accuracy Studies version 2 (QUADAS-2 was applied to determine risk of bias and applicability. Diagnostic performances were assessed using the likelihood ratio test for sensitivity and specificity and the Wald test for PPV. The significance level was P < 0.05. 17% (2/12) of the studies were considered low risk of bias (244 liver observations; 164 patients). When compared to v2018, mLR-5 demonstrated higher sensitivity (61.3% vs. 46.5%, P < 0.001), similar PPV (85.3% vs. 86.3%, P = 0.89), and similar specificity (85.8% vs. 90.8%, P = 0.16) for HCC. This study confirms mLR-5 has higher sensitivity than LR-5 for HCC identification, while maintaining similar PPV and specificity, validating the mLI-RADS proposal in a heterogeneous, international cohort. 3 TECHNICAL EFFICACY: Stage 2.

Cognitive and Functional Connectivity Outcomes from a Phase I Trial of Accelerated High‐Dose Repetitive Transcranial Magnetic Stimulation in Amnestic MCI

AbstractBackgroundRepetitive transcranial magnetic stimulation (rTMS), most widely used to treat depression, may have secondary benefits for cognition. Accelerated high‐dose protocols such as intermittent theta burst (iTBS)‐rTMS shorten the treatment course by &gt;50%, potentially improving the feasibility of use in patients with cognitive impairments. Here, we present the results of a phase I trial of iTBS‐rTMS for improving cognition in individuals with amnestic mild cognitive impairment (aMCI) and we explore whether functional brain changes relate to improved cognition.MethodTwenty‐two patients with clinically diagnosed aMCI received 24 sessions of open‐label iTBS‐rTMS to left dorsolateral prefrontal cortex (l‐dlPFC) over 3 days. Nineteen had complete brain MRI and cognitive testing pre‐ and immediately post‐treatment. The primary cognitive outcome was the norm‐adjusted fluid cognition composite T‐score from the NIH Toolbox Cognition Battery. Resting‐state functional connectivity was computed from subject‐specific parcellations mapped to each individual’s functional topology. We examined changes in connectivity within and between the FPN (of with the l‐dlPFC is a hub) and networks implicated in cognition (FPN, dorsal and ventral attention, limbic, default mode). We assessed whether connectivity changes (post minus pre) related to change in fluid cognition.ResultWe achieved a high retention rate of 95%. Treatment with iTBS‐rTMS was safe, with no adverse neuroradiological, neuropsychiatric, or neurocognitive effects. Side effects were minimal and acceptability ratings were high. Treatment produced significant, large effect size (d = 0.98) improvements in fluid cognition (Fig. 1A), and we observed preliminary evidence of related changes in functional connectivity. Specifically, there was a numerical increase in within‐FPN connectivity and a marginally significant increase in connectivity between cognitive networks (Fig. 1B). Further, there was a medium‐strength and marginally significant association between increased within‐FPN connectivity and improved fluid cognition (Fig. 1C).ConclusionThis phase I trial demonstrated that iTBS‐rTMS is safe, feasible, and acceptable in aMCI. Although not dosed for efficacy, we observed large improvements in fluid cognition and preliminary evidence of increased functional connectivity in expected brain networks that related to improved cognition. These promising results support iTBS‐rTMS as potentially efficacious in improving cognition in aMCI, directly informing larger, planned follow‐up randomized controlled phase II trials.

Radiological Verses Histological Evaluation of Spinal Space Occupying Lesions

Objective: This study set out to evaluate radiology's diagnostic capacity in accurately establishing a preliminary working diagnosis for various spine tumor types. Materials and Methods: This is a prospective study carried out and examined patients who had surgical resection with the collection of histopathology samples, regardless of age or gender. A full MRI examination from every angle and contrast-enhanced pictures were required. Inclusion criteria consisted of Patients of all ages of both genders, who underwent surgery a tissue sample was collected for histopathological diagnoses, and a complete MRI study with all views and contrast-enhanced images was available to give a preliminary diagnosis. Results: Based on the evaluation by the senior radiologists, the lesions were most commonly intradural-extramedullary (50%) in position according to the dura, followed by intramedullary in 14 (26.9%) patients. Despite our series having a total of 16 misdiagnosed cases, the overall diagnostic accuracy of the MRI remained high at 69.2%. Conclusion: MRI has superior diagnostic accuracy in diagnosing meningiomas as compared to nerve sheath tumors such as meningiomas. It also has good predictive accuracy of intramedullary lesions such as ependymomas.

#382 : Congenital Adrenal Hyperplasia with Concomitant Mullerian Agenesis: A Rare Occurance in 46 XX Disorders of Sexual Development (DSD)

Background and Aims: The most common cause of 46 XX DSD is due to congenital adrenal hyperplasia with varying degree of virilization. Females with CAH do not produce anti mullerian hormone (AMH), therefore the internal genitalia, which are mullerian derivatives, are develop normally. We report a unique case of CAH with absent uterus, cervix, and fallopian tube. Method: The clinical, laboratory, and imaging findings of the patient are presented with literature review. Results: We report an ongoing case of a 20-year-old patient with ambiguous genitalia and primary amenorrhea. She was born from a healthy mother and raised as a female. There was no family history of the same disorder. On physical examination we found that she had normal height, normal blood pressure, palatoschizis, undeveloped breast (Tanner stage 1), and clitoral virilization with single urovaginal opening (Prader stage 3). We performed a G-Banded chromosome analysis, with 46 XX results. Laboratory test showed her 17-hidroxyprogesterone level was 176,93 ng/ml, FSH level was 3,06 mIU/ml, LH level was 2,21 mIU/ml, and estradiol level was 18,0 pg/mL. Ultrasound imaging revealed the absence of uterus, cervix, and vagina, as well as abnormal appearance of ovarium. We have planned to perform a complete MRI study for other anomalies as we suspected this patient had Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome type II. Conclusion: In the presence of external genitalia and urinary tract malformations in patients with CAH, it is important to investigate for possible associated mullerian anomalies. A comprehensive approach in diagnosis could lead to a better outcome in a patient’s treatment and wellbeing.

Uptake of screening MRI in high risk patients without a personal history of breast cancer.

133 Background: The American Cancer Society (ACS) recommends breast MRI in addition to annual screening mammogram for women who are high risk for breast cancer starting at age 30, regardless of breast density. This includes women with a lifetime risk of breast cancer of 20% or greater, according to breast cancer risk assessment tools. In this study, we evaluated the uptake of supplemental MRI screening in patients ages 25-75 classified as high risk (Tyrer Cuzick (TC) score greater than 20%), without a personal history of breast cancer (PHBC). Methods: Cancer risk assessment software was used to calculate a TC score. Data was extracted from the EMR of an academic center for patients ages 25-75 years old between 07/20/2020 and 07/29/2021 with a TC score of ≥ 20%. Factors such as age, ethnicity, race, insurance type, breast density, and whether patients had access to a High-Risk Breast Cancer (HRBC) provider were analyzed and a chi-squared test was used to determine whether there were significant differences in MRI supplemental uptake based on these subsets. Results: 1144 patients were identified as high risk, having a TC ≥ 20%. 27% (n=307) underwent supplemental MRI screening, while 73% (n=837) did not. 842 patients were classified as having dense breasts and 28% (n=237) of these patients underwent MRI. Of 635 patients with an MRI order, 36% (n=227) had access to a HRBC provider, while 64% (n=408) did not. Patients with a HRBC provider were more likely to fulfill their MRI order (88%, n=200), compared to patients without a HRBC provider (33%, n=135) (p&lt;0.001). Conclusions: Various factors may be influencing whether high risk patients complete supplemental screening MRI. Patients with dense breasts and those with access to HRBC were more likely to undergo supplemental MRI screening. Patients who have not completed their recommended breast MRI may be faced with various challenges, such as, not having access to a HRBC provider. Identifying barriers to screening can help increase early rates of breast cancer detection in this high risk population of women.

Pattern of Brain Parenchymal Damage Related to Cerebral Small Vessel Disease in Carriers of Rare NOTCH3 Variants.

Previous studies reported that carriers of rare NOTCH3 variants comprised more than 10% of the general population and are susceptible to a heavy overall burden of cerebral small vessel disease while the injury patterns remain uncovered. This study aimed to investigate the imaging features in relation to rare NOTCH3 variants and the interaction between cortical atrophy and white matter lesions from a longitudinal view, with respect to spatial and dynamic patterns. As part of a community-based cohort, we included participants with complete whole-exome sequencing and brain MRI in the baseline analysis. All participants were invited for a 5-year follow-up MRI, and those who did not complete the follow-up were excluded from the longitudinal analysis. NOTCH3 variants with minor allele frequency <1% in all 4 public population databases were defined as rare variants. We used general linear models to compare the volume of white matter hyperintensity (WMH) volume and brain parenchymal fraction between rare NOTCH3 variant carriers and noncarriers. In addition, we compared the WMH probability map and vertex-wise cortex maps at a voxel/vertex-wise level. A total of 1,054 participants were included in baseline analysis (13.56% carried rare NOTCH3 variants), among whom 661 had a follow-up brain MRI (13.76% carried rare NOTCH3 variants). Rare NOTCH3 variant carriers had a heavier white matter hyperintensity burden (1.65 vs 0.85 mL, p = 0.025) and had more extensive WMH distributed in the periventricular areas. We also found that rare NOTCH3 variant carriers were susceptible to worse cortical atrophy (β = -0.004, SE = 0.002, p = 0.057, adjusted for age and sex). Cortical atrophy of multiple regions in the frontal and parietal lobes was related to white matter hyperintensity progression. Individuals with rare NOTCH3 variants have a distinct pattern of brain parenchymal damage related to CSVD. Our findings uncover the important genetic predisposition in age-related cerebral small vessel disease in the general population.

P13.01.A POST-OPERATIVE MRI SYNTHESIS FROM PRE-OPERATIVE MRI AND POST-OPERATIVE CT USING CONDITIONAL GAN FOR THE ASSESSMENT OF DEGREE OF RESECTION

Abstract BACKGROUND Magnetic resonance imaging (MRI) is an essential part of assessing the extension of resection after craniotomy, allowing for accurate assessment of the brain. However, the application of MRI within 72 hours after surgery is limited, owing to its high cost, long time duration, and patients’ limited mobility. Besides, MRI excludes people with contraindications, including implantable electronic devices or artificial limbs, in which sceneries computerized tomography (CT) is the only available choice. To overcome these limitations, we investigated the use of a deep learning model for synthesizing post-operative MRI images. MATERIAL AND METHODS We aim to employ Cross-domain Correspondence Learning for Exemplar-based Image Translation Network (CoCosNet), an exemplar-based image translation model to synthesize T1 contrast-enhanced (T1ce) MRI images by combining post-operative T1ce and post-operative CT images. 233 cases were retrospectively collected at Sun Yat-sen University Cancer Center, who underwent complete MRI and CT scans. RESULTS After 200 epochs and a batch size of 10, CoCosNet achieved comparable results compared to other existing models, with objective indicators structural similarity index = 0.75, peak signal-to-noise ratio = 21.68, and mean absolute error = 0.007. Furthermore, assessments of the extent of resection between the true and synthesized T1ce images achieve great consistency. CONCLUSION Our study demonstrates the effectiveness of the CoCosNet deep learning model in synthesizing post-operative MRI images from pre-operative MRI and post-operative CT scans. Our quantitative analysis indicates that the synthesized images have comparable quality to real MRI images and are able to accurately assess the extent of resection. This approach has a promising future by providing a reliable alternative to traditional post-operative MRI.