Septal Enhancement Research Articles

MRI analysis of simple and aneurysmal bone cysts in the proximal humerus: what actually matters in clinical routine.

To evaluate magnetic resonance imaging (MRI) characteristics of simple and aneurysmal bone cysts (SBC/ABC) of the proximal humerus and the intermittent difficulty in the imaging differentiation between the two in daily clinical routine. MR images of 26 patients with suspected SBC/ABC in the proximal humerus were retrospectively assessed by two independent radiologists blinded to the final histological result. Based on a standard MRI protocol, different morphologic features and signal intensities of the lesion on non-enhanced and enhanced sequences were documented. The radiological diagnosis was correlated with histology. Eighteen patients had the image-based diagnosis of an SBC, yet the histology confirmed only 12, the residual 6 were identified as an ABC, despite the imaging criteria corresponding unambiguously to the former. One of the main reasons was the unicameral morphology of lesions, found in 9/14 (64.3%) cases of all ABCs, i.e., in 19/26 cases in total. Therefore, the sensitivity of the radiological diagnosis was moderate (57.14%), yet specificity very high (100%). In total, 69.2% (18/26) presented with a pathological fracture at admission, which correlated strongly with both circumferential (MCC = 0.65, p = 0.01) and septal (MCC = 0.42, p = 0.06) enhancement patterns. Circumferential enhancement was also found to correlate strongly with the histological diagnosis, being recognized in all cases of ABC (MCC = 0.44, p = 0.06). MRI characteristics of ABCs/SBCs in the proximal humerus are indifferent and ABCs may morphologically present as SBCs. Radiologists should be aware of the different, often confusing presentation of both entities in daily clinical routine.

Septal late gadolinium enhancement on Cardiac MRI predicts failure to achieve left bundle pacing

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): British Heart Foundation Background; Left bundle area pacing is a novel technique that provides direct stimulation of cardiac conduction tissue in order to deliver physiological ventricular activation. The approach for left bundle area pacing is transseptal lead implantation, where the lead is advanced from the right ventricular side of the septum to the left ventricular side to capture the proximal left bundle. Observational data suggests that whilst this is a safe and feasible method, implant success rate is not 100%, and appears to be lower in patients with a cardiac resynchronization therapy (CRT) indication rather than a bradycardia indication for pacing. The mechanisms for failure to advance the lead through the ventricular septum are not well understood. Purpose; We used pre-procedural CMR to determine whether there are features which can help identify patients where lead implantation may be challenging. We assessed whether the extent and location of septal late gadolinium enhancement identified patients in whom left bundle area pacing will be challenging. We hypothesized that the presence of extensive scar in the septum impedes advancing the lead to the left ventricular septum and prevents capture of the left bundle. Methods; Patients underwent cardiac MRI including motion corrected free-breathing late gadolinium enhancement imaging1 before implantation. Scar was quantified using the full height half maximum method and expressed as the overall proportion of myocardial mass in the basal anteroseptal and basal inferoseptal segments, as shown in Figure 1. Left bundle area pacing was then attempted in patients with a CRT indication for pacing. We compared the extent of septal scar between patients in whom left bundle area pacing was achieved and those where there was failure to advance the lead deep into the septum. Results; 12 patients (11 male, 1 female), with average age 72 (IQR 63 to 78) and LVEF 30% (IQR 26 to 33) were studied. There was failure to advance the lead deep into the septum in 4 patients. There was a significantly higher basal septal scar burden in those patients where there was failure to advance the left bundle lead compared to those in which left bundle capture was achieved as shown in Figure 2 (median 55% and 5% respectively, p-value 0.02 by Wilcoxon signed rank test). Conclusion; The presence and extent of late gadolinium enhancement in the basal septum appears to be an important determinant of successful implantation of left bundle pacing lead using current implant technology. This may be because extensive septal scar prevents advancement of the pacing lead through the septum. Cardiac MRI before left bundle area pacing is likely to be useful in procedural planning.

Lymphangioma of popliteal fossa masquerading as Baker\u2019s cyst

BackgroundLymphatic malformations are the second most common vascular malformations after venous malformations. These slow-flow lesions occur most often in the paediatric population and seldom in the extremities. We report a case of lymphangioma at the popliteal fossa in an adult who underwent complete surgical resection.Case presentationA 30-year-old male presented to the department of orthopaedics with a swelling in the right calf region. Clinically, it was suspected to be a Baker’s cyst. Ultrasound showed a multiloculated anechoic cystic lesion in the inferior aspect of popliteal fossa along the intermuscular plane with multiple internal septations. Infected Baker’s cyst was considered, and MRI was suggested for further evaluation. On MRI, the lesion measured 7.2 × 4.6 × 5.8 cm, appeared as a low signal on T1 and high signal on STIR and T2, with multiple internal septations and was situated in the inferior aspect of the right popliteal fossa along the intermuscular plane between the lateral head of gastrocnemius and soleus muscles. No obvious synovial extension. A post-contrast study showed minimal peripheral and septal enhancement. Neither internal enhancing solid components nor significant internal derangement of the knee was observed. Diagnosis of lymphangioma was considered based on the imaging features and ruling out the common differentials for cystic lesions around the knee. Wide local excision was performed. Histopathological evaluation showed multiple irregularly dilated lymphatic channels lined by flatted epithelium. The lymphatic channels were seen to be surrounded by thick fibro collagenous cyst wall with scattered congested blood vessels, skeletal muscle fibre and chronic inflammatory cells.ConclusionLymphangioma must be included in the differential diagnosis of any cystic lesion if the lesion appears multiseptated and/or infiltrative. At the popliteal fossa, it presents as a multiseptated cyst with no synovial continuity or internal derangement of the knee.

Atrial edema in patients with atrial fibrillation with chronic heart failure

Abstract Funding Acknowledgements Type of funding sources: None. Objective to investigate the intensity of the atrial septum by T2-weighted magnetic resonance imaging (MRI) in patients with chronic heart failure (CHF), with and without atrial fibrillation (AF). Materials and methods. In patients with CHF with atrial fibrillation (n = 23, including 11 patients with paroxysmal form, and 12 patients with constant forms) and without (n = 9) of arrhythmias in the control group – almost healthy (n = 6) we evaluated the signal intensity (SI) of the interatrial septum, the interventricular septum, and skeletal muscle at MRI T-2 weighted images. An increase in the value of SI in 2 times or more compared with the SI of skeletal muscle was regarded as an MRI signs of myocardial edema. Results. The SI of the atrial septum in patients with CHF who have constant forms of atrial fibrillation is higher than in the control (2775.58 ± 383.61 relative to the control - 1448.57 ± 291.30, p < 0.05). The MPP gain index in patients with paroxysmal AF equal to 1.59 ± 0.10 did not differ in comparison with patients with CHF who do not have rhythm disorders - 1.53 ± 0.12. An index of atrial septal enhancement greater than 2, indicating the presence of MRI signs of atrial septal myocardial edema was detected only in patients with a constant form of AF (2.39 ± 0.18) than in patients with CHF with paroxysmal AF, in patients with CHF without rhythm disturbances and in the control group (1.59 ± 0.23; 1.53 ± 0.28 and 1.15 ± 0.16, respectively, p < 0.05). Summary. In patients with CHF who have a constant form of atrial fibrillation, according to T2-weighted MRI images, signs of edema of the myocardium of the atrial septum were revealed in comparison with the control group and patients with CHF who have a paroxysmal form of atrial fibrillation and without rhythm disturbances.

Cardiovascular magnetic resonance evaluation of soldiers after recovery from symptomatic SARS-CoV-2 infection: a case\u2013control study of cardiovascular post-acute sequelae of SARS-CoV-2 infection (CV PASC)

BackgroundMyocarditis is a potential complication after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and a known cause of sudden cardiac death. Given the athletic demands of soldiers, identification of myocarditis and characterization of post-acute sequelae of SARS-CoV-2 infection with cardiovascular symptoms (CV PASC) may be critical to guide return-to-service. This study sought to evaluate the spectrum of cardiac involvement among soldiers with cardiopulmonary symptoms in the late convalescent phase of recovery from SARS-CoV-2 compared to a healthy soldier control group, and to determine the rate of progression to CV PASC.MethodsAll soldiers referred for cardiovascular magnetic resonance (CMR) imaging for cardiopulmonary symptoms following COVID-19 were enrolled and matched by age, gender, and athletic phenotype 1:1 to soldiers undergoing CMR in the year prior to the first case of COVID-19 at our institution. Demographic, clinical, laboratory, and imaging parameters were compared between groups. The diagnosis of acute myocarditis was made using modified Lake Louise criteria. Wilcoxon rank sum and chi-squared tests were used for comparison of continuous and categorical variables, respectively.ResultsFifty soldier cases and 50 healthy soldier controls were included. The median time from SARS-CoV-2 detection to CMR was 71 days. The majority of cases experienced moderate symptoms (N = 43, 86%), while only 10% required hospitalization. The right ventricular (RV) ejection fraction (RVEF) was reduced in soldier cases compared to controls (51.0% vs. 53.2%, p = 0.012). Four cases were diagnosed with myocarditis (8%), 1 (2%) was diagnosed with Takotsubo cardiomyopathy, and 1 (2%) had new biventricular systolic dysfunction of unclear etiology. Isolated inferior RV septal insertion late gadolinium enhancement (LGE) was present in 8 cases and 8 controls (16% vs. 24%, p = 0.09).Seven of the 19 (37%) cases that completed an intermediate-term follow-up survey reported CV PASC at a median of 139 days of follow-up. Two of the 7 soldiers (29%) with CV PASC had a pathological clinical diagnosis (myocarditis) on CMR.ConclusionsCardiovascular pathology was diagnosed in 6 symptomatic soldiers (12%) after recovery from SARS-CoV-2, with myocarditis found in 4 (8%). RVEF was reduced in soldier cases compared to controls. CV PASC occurred in over one-third of soldiers surveyed, but did not occur in any soldiers with asymptomatic acute SARS-CoV-2 infection.

Predictors of the presence of septal late gadolinium enhancement in follow-up cardiac magnetic resonance imaging and its relation to acute myocarditis prognosis

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Acute myocarditis (AM) is generally a self-limited and benign disease. However, a minority of patients (pts) present or develop adverse outcomes. It has been proposed that the presence of late gadolinium enhancement (LGE) in the septum is associated with worse prognosis. Also, the presence of LGE without oedema in follow-up cardiac magnetic resonance imaging (CMR) seems to reflect more permanent lesions. Purpose The aim of this study was to determine if the presence of septal LGE in acute-phase CMR was associated with higher extent of disease in follow-up CMR and if initial laboratory tests help to predict the evolution to more permanent lesions. Methods Prospective single-centre study of pts admitted with AM diagnosed according to clinical findings, troponin T elevation and CMR criteria (Lake Louise), since 1/2013. Selection of those who underwent acute-phase (CMR-I) and follow-up CMR (CMR-II). Results Of 88 pts admitted with AM, 46 fulfilled our inclusion criteria: median age 31 ± 13 years, 85% males. CMR-I was performed at 6 ± 5days and LGE was present in 43 pts (93.5%). CMR-II was performed at 8 ± 4.3 months and 29 pts (63%) improved the number of LGE-positive segments, 10 pts (21.8%) had stable disease and 7 pts (15.2%) worsened CMR findings. Septal-LGE was detected in 10 pts (21.7%) in CMR-I and in 6 pts (13.0%) in CMR-II. Logistic regression analysis identified septal-LGE in CMR-I as a predictor of higher extent of LGE in CMR-II (OR 1.4, 95%CI 1.1-1.9, p = 0.020). Although median values of maximum high-sensitivity troponin and reactive-C protein (RCP) were not associated with septal LGE in CMR-I, increasing values of such tests were univariate predictors of a higher likelihood of septal involvement in CMR-II: maximum troponin (886 vs 1852ng/L; OR 1.00, 95%CI 1.00-1.00 p = 0.017) and RCP (4.2 vs 13.9mg/dL; OR 1.17, 95%CI 1.04-1.33, p = 0.012). After multivariate analysis, RCP was the independent predictor of septal LGE in CMR-II (AUC 80.8, 0.97-0.91, p = 0.012). RCP cut-off value >10.2mg/dL identified patients with septal LGE in CMR-II with a sensitivity and specificity of 83.3% and 85.0%, respectively. The presence of cardiovascular risk factors, clinical presentation and B-type natriuretic peptide values were not predictors of septal LGE in either CMR. In a mean clinical follow-up of 757 ± 476days, no patient died, 3 pts (6.5%) developed new-onset heart failure (NYHA class II functional symptoms) and 2 pts (4.3%) developed ventricular arrhythmias. Due to a small number of adverse events, neither laboratory tests nor LGE septal pattern predicted adverse outcomes. Conclusions In this population, septal LGE pattern was able to predict higher extent of LGE in follow-up CMR. Increased cardiac biomarkers and inflammatory proteins in the acute setting were also associated with septal involvement in follow-up and can potentially help to establish the risk of adverse events for patients admitted with acute myocarditis.

Recognition of acute myocardial infarction caused by spontaneous coronary artery dissection of first septal perforator.

Spontaneous coronary artery dissection (SCAD) diagnosis is challenging as angiographic findings are often subtle and differ from coronary atherosclerosis. Herein, we describe characteristics of patients with acute myocardial infarction (MI) caused by first septal perforator (S1) SCAD. Patients were gathered from SCAD registries at Minneapolis Heart Institute and Vancouver General Hospital. First septal perforator SCAD prevalence was 11 of 1490 (0.7%). Among 11 patients, age range was 38-64 years, 9 (82%) were female. Each presented with acute chest pain, troponin elevation, and non-ST-elevation MI diagnosis. Initial electrocardiogram demonstrated ischaemia in 5 (45%); septal wall motion abnormality was present in 4 (36%). Angiographic type 2 SCAD was present in 7 (64%) patients with S1 TIMI 3 flow in 7 (64%) and TIMI 0 flow in 2 (18%). Initial angiographic interpretation failed to recognize S1-SCAD in 6 (55%) patients (no culprit, n = 5, septal embolism, n = 1). First septal perforator SCAD diagnosis was established by review of initial coronary angiogram consequent to cardiovascular magnetic resonance (CMR) demonstrating focal septal late gadolinium enhancement with corresponding oedema (n = 3), occurrence of subsequent SCAD event (n = 2), or second angiogram showing healed S1-SCAD (n = 1). Patients were treated conservatively, each with ejection fraction >50%. First septal perforator SCAD events may be overlooked at initial angiography and mis-diagnosed as 'no culprit' MI. First septal perforator SCAD prevalence is likely greater than reported herein and dependent on local expertise and availability of CMR imaging. Spontaneous coronary artery dissection events may occur in intra-myocardial coronary arteries, approaching the resolution limits of invasive coronary angiography.

Evaluation of idiopathic dilated cardiomyopathy with cardiac magnetic resonance imaging

Purpose: The present study was aimed to assess the prevalence, location, and patterns of late gadolinium enhancement (LGE) in idiopathic dilated cardiomyopathy (DCM) on cardiac magnetic resonance (CMR) imaging and to correlate the left ventricular (LV) functions obtained by cine CMR with the values obtained by echocardiography. Methods: This was a prospective single-center study covering a 2-year study period. The authors studied the prevalence, location, and patterns of LGE in idiopathic DCM on CMR and correlated the ventricular functions obtained by CMR with those obtained by echocardiography. Results: LGE was seen in 18/40 (45%) and was absent in 22/40 (55%) of patients. With regard to location, septal enhancement was the most common, seen in 8 (20%) followed by free-wall enhancement in 4 (10%) and a concomitant septal and free-wall enhancement in 6 (15%). In terms of pattern, midwall enhancement was observed in 10 (25%), subepicardial in 2 (5%), subendocardial in 4 (10%), and focal and transmural enhancement in 1 each. The maximum correlation for calculation of LV ejection fraction (EF) was obtained between CMR and two-dimensional echocardiography (P = 0.442). Conclusion: CMR is an accurate tool to determine the phenotype of DCM by identifying the presence, location, and pattern of LGE which has a prognostic value and is used to guide management. CMR is the most accurate assessment tool for the calculation of EF and other volumetric variables in DCM.

An Update on Clinicopathological, Imaging and Genetic Features of Desmoplastic Fibroblastoma (Collagenous Fibroma).

Desmoplastic fibroblastoma (also known as collagenous fibroma) is an uncommon benign fibroblastic/myofibroblastic neoplasm that primarily arises in the subcutaneous tissue of upper extremity. Magnetic resonance imaging reveals a well-defined mass in intimate association with dense connective tissue and prominent low signal intensity on all pulse sequences. Peripheral and septal enhancement is usually seen after intravenous contrast. Histologically, the lesion is paucicellular and consists of spindle to stellate-shaped cells embedded in a collagenous or myxocollagenous stroma with low vascularity. Diffuse and strong nuclear immunoreactivity for FOS-like antigen 1 seems to be characteristic of desmoplastic fibroblastoma. Cytogenetic studies have demonstrated the presence of 11q12 rearrangements and an identical t(2;11)(q31;q12) translocation. This review provides an updated overview of the clinical, radiological, histological, cytogenetic and molecular genetic features of desmoplastic fibroblastoma and discusses the relationship to fibroma of tendon sheath.

Hepatic Mucinous Cystic Neoplasm Versus Simple Biliary Cyst: Assessment of Distinguishing Imaging Features Using CT and MRI.

OBJECTIVE. The purpose of our study was to identify the imaging features that differentiate a hepatic mucinous cystic neoplasm (MCN) from a simple biliary cyst. MATERIALS AND METHODS. Surgically resected hepatic MCNs and simple biliary cysts over a 20-year period (October 29, 1997-January 23, 2018) with preoperative CT, MRI, or both were retrospectively identified. Included cases underwent histopathologic confirmation of diagnosis based on the 2010 World Health Organization criteria and blinded imaging review. Various imaging features, including cyst shape and septal enhancement, were assessed for performance. For septate cysts, the relationship of the septation to the cyst wall-that is, arising from the wall without an indentation versus arising from an external macrolobulation-was recorded. Statistical analysis was performed for the imaging features with the chi-square test. RESULTS. The study group comprised 22 hepatic MCNs and 56 simple biliary cysts. A unilocular hepatic cystic lesion was highly predictive of a simple biliary cyst (positive predictive value = 95.2%). The imaging feature of septations arising only from macro-lobulations was 100% specific for a simple biliary cyst on CT (p = 0.001). The presence of septations arising from the cyst wall without indentation was 100% sensitive for hepatic MCN but was only 56.3% specific on CT. Septal enhancement reached 100% sensitivity for hepatic MCN on MRI (p = 0.018). CONCLUSION. The presence of septations, relationship of the septations to the cyst wall, and septal enhancement were sensitive imaging features in the detection of hepatic MCN. The imaging feature of septations arising only from macrolobulations in the cyst wall was specific for simple biliary cysts on CT and helped differentiate simple biliary cysts from hepatic MCNs.

Contrast-enhanced ultrasound (CEUS) of cystic renal lesions in comparison to CT and MRI in a multicenter setting.

Contrast-enhanced-ultrasound (CEUS) has been frequently used in assessment of cystic renal lesions. The aim of this study was to investigate the Bosniak classification in CEUS compared to CT and MRI in a multi-center setting. Bosniak classification in CEUS examinations of cystic renal lesions were compared to imaging findings in computed-tomography (ceCT) and magnetic-resonance-imaging (ceMRI). Imaging results were correlated to histopathological reports. All examinations were performed by experts (EFSUMB level 3) using up-to-date CEUS examination-protocols. Overall, 173 cystic renal lesions were compared to subgroups CT (n = 87) and MRI (n = 86). Using Bosniak-classification 64/87 renal cysts (73.6%) were rated equal compared to CT with upgrade of four lesions (4.6%) and downgrade of 19 lesions (21.8%) by CT (Intra-class-correlation [ICC] coefficient of 0.824 [p < 0.001]). CEUS compared to MRI, presenting different scoring especially in classes Bosniak IIF (n = 16/31) and Bosniak III (n = 16/28) with an ICC coefficient of 0.651 (p < 0.001). CEUS can visualize even finest septal and small nodular wall enhancement, which may result in an upgrade of cystic lesions into a higher Bosniak class compared to CT or MRI. Thus, a modification of the Bosniak classification on CEUS may reduce unnecessary biopsies and surgery.

Differential diagnosis of sinonasal extranodal NK/T cell lymphoma and diffuse large B cell lymphoma on MRI

PurposeTo evaluate whether imaging features on conventional magnetic resonance imaging (MRI) can differentiate sinonasal extranodal natural killer/T cell lymphomas (ENKTL) from diffuse large B cell lymphoma (DLBCL).MethodsConsecutively, pathology-proven 59 patients with ENKTL and 27 patients with DLBCL in the sinonasal region were included in this study. Imaging features included tumor side, location, margin, pre-contrast T1 and T2 signal intensity and homogeneity, post-contrast enhancement degree and homogeneity, septal enhancement pattern, internal necrosis, mass effect, and adjacent involvements. These imaging features for each ENKTL or DLBCL on total 86 MRI scans were indicated independently by two experienced head and neck radiologists. The MRI-based performance in differential diagnosis of the two types of lymphomas was evaluated by multivariate logistic regression analysis.ResultsAll ENKTLs were located in the nasal cavity, with ill-defined margin, heterogeneous signal intensity, internal necrosis, marked enhancement of solid component on MRI, whereas DLBCLs were more often located in the paranasal sinuses, with MR homogenous intensity, mild enhancement, septal enhancement pattern, and intracranial or orbital involvements (all P < 0.05). Using a combination of location, internal necrosis and septal enhancement pattern of the tumor in multivariate logistic regression analysis, sensitivity, specificity, and accuracy in differential diagnosis of ENKTL and DLBCL were 100%, 79.4%, and 91.9%, respectively, for radiologist 1, and were 98.3%, 81.5%, and 93.0%, respectively, for radiologist 2.ConclusionMRI can effectively differentiate ENKTL from DLBCL in the sinonasal region with a high diagnostic accuracy.

An MRI-based decision tree to distinguish lipomas and lipoma variants from well-differentiated liposarcoma of the extremity and superficial trunk: Classification and regression tree (CART) analysis

PurposeTo build and validate a decision tree model using classification and regression tree (CART) analysis to distinguish lipoma and lipoma variants from well-differentiated liposarcoma of the extremities and superficial trunk. MethodsThis retrospective study included patients who underwent surgical resection and preoperative contrast-enhanced MR imaging for lipoma, lipoma variants, and well-differentiated liposarcoma in two tertiary referral centers. Six MRI findings (tumor size, anatomical location, tumor depth, shape, enhancement pattern, and presence of intermingled muscle fibers) and two demographic factors (patient age and sex) were assessed to build a classification tree using CART analysis with minimal error cross-validation pruning based on a complexity parameter. ResultsThe model building cohort consisted of 231 patients (186 lipoma and lipoma variants and 45 well-differentiated liposarcoma) from one center, while the validation cohort consisted of 157 patients (136 lipoma and lipoma variants and 21 well-differentiated liposarcoma) from another center. In the CART analysis, the contrast enhancement pattern (no enhancement or thin septal enhancement versus thick septal, nodular, confluent hazy, or solid enhancement) was the first partitioning predictor, followed by a maximal tumor size of 12.75 cm. The tree model allowed distinction of lipoma and lipoma variants from well-differentiated liposarcoma in both the model building cohort (C-statistics, 0.955; sensitivity 80 %, specificity 94.62 %, accuracy 91.77 %) and the external validation cohort (C-statistics, 0.917; sensitivity 66.67 %, specificity 95.59 %, accuracy 91.72 %). ConclusionThe distinction of lipoma and lipoma variants from well-differentiated liposarcoma can be achieved with the simple classification tree model.

Chronic invasive fungal rhinosinusitis vs sinonasal squamous cell carcinoma: the differentiating value of MRI.

To investigate MRI features in discriminating chronic invasive fungal rhinosinusitis (CIFRS) from sinonasal squamous cell carcinomas (SNSCC). MRI findings of 33 patients with CIFRS and 47 patients with SNSCC were retrospectively reviewed and compared. Multivariate logistic regression analysis was performed to identify significant imaging features in distinguishing between CIFRS and SNSCC. The ROC curves and the AUC were used to evaluate diagnostic performance. There were significant differences in cavernous sinus involvement (p < 0.001), sphenoid sinus involvement (p < 0.001), meningeal involvement (p = 0.024), T2 signal intensity (p =0.006), and enhancement pattern (p < 0.001) between CIFRS and SNSCC. Multivariate logistic regression analysis identified cavernous sinus involvement (odds ratio [OR] = 0.06, 95% confidence interval [95% CI] = 0.02-0.20) and sphenoid sinus involvement (OR = 0.14, 95% CI = 0.05-0.45) as significant indicators for CIFRS and T2 isointensity to gray matter (OR = 4.44, 95% CI = 1.22-16.22) was a significant indicator for SNSCC. ROC curve analysis showed the AUC from a combination of three imaging features was 0.95 in differentiating CIFRS and SNSCC. MRI showed significant differences between CIFRS and SNSCC features. In immunocompromised patients, a sinonasal hypointense mass on T2WI with septal enhancement or loss of contrast enhancement, and involvement of cavernous sinus, sphenoid sinus, and meninges strongly suggest CIFRS. • Chronic invasive fungal rhinosinusitis (CIFRS) is often difficult to distinguish from sinonasal squamous cell carcinomas (SNSCC) in clinical practice. • Cavernous sinus and sphenoid sinus involvement appear to be significant indicators for CIFRS. T2 isointensity to gray matter appears to be a significant indicator for SNSCC. • Loss of contrast enhancement and septal enhancement can be used to distinguish CIFRS from SNSCC with a high degree of specificity.

The differentiation between aneurysmal bone cyst and telangiectatic osteosarcoma: a clinical, radiographic and MRI study

Aneurysmal bone cyst (ABC) and telangiectatic osteosarcoma (TOS) share several clinical and imaging features, including young presentation, long bone involvement, lytic appearance on radiography and fluid-fluid levels on MRI. Therefore, they may be difficult to differentiate. The aim of this study is to identify clinical, radiological and MRI features which aid differentiation of the two lesions. Retrospective review of all histologically confirmed ABC and TOS over an 11-year period. Data recorded include age at presentation, sex, skeletal location and various radiographic and MRI features. This retrospective study included 183 patients, 92 males and 91 females. Mean age at presentation of 18.4years (range 1-70years); 152 cases of ABC and 31 TOS. No significant difference between age and sex. TOS was significantly less likely to involve the axial skeleton; no difference related to location within the bone. Radiographic findings significantly favouring ABC included a less aggressive pattern of bone destruction, a purely lytic appearance, an expanded but intact cortex, no periosteal response and no soft tissue mass. MRI features significantly favouring ABC included smaller tumour size (maximum mean dimension 46mm compared to 95mm for TOS), absence of soft tissue mass, > 2/3 of the lesion filled with fluid levels and thin septal enhancement following contrast. Several radiographic and MRI features aid in the differentiation between ABC and TOS. Lesions with a geographic Type 1A or IB pattern of bone destruction which are completely filled with FFLs on MRI can confidently be diagnosed as ABC.

Correlation between septal midwall late gadolinium enhancement on CMR and conduction delay on ECG in patients with nonischemic dilated cardiomyopathy

BackgroundSeptal midwall late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMR) is a characteristic finding in nonischemic dilated cardiomyopathy (DCM) and is associated with adverse cardiac events. QRS-prolongation in DCM is also frequently present and a predictor of arrhythmic events and mortality. Since the His-Purkinje fibres are located in the interventricular septum, QRS-prolongation may directly result from septal fibrosis, visualized by LGE. Our aim was to study the correlation of the presence and extent of septal midwall LGE and QRS-duration. MethodsDCM-patients with left ventricular (LV) dysfunction (LVEF < 50%) were included. LV volumes, systolic function and nonischemic septal midwall LGE, defined as patchy or stripe-like LGE in the septal segments, were quantified. QRS-duration on standard 12-lead ECG was measured. Results165 DCM-patients were included (62% male, mean age 59 ± 15 years) with a median LVEF of 36% [24–44]. Fifty-one patients (31%) demonstrated septal midwall LGE with a median extent of 8.1 gram [4.3–16.8]. Patients with midwall LGE had increased LV end-diastolic volumes (EDV) 248 mL [193–301] vs. 193 mL [160–239], p < 0.001) and lower LVEF (26% [18–35] vs. 40% [32–45], p < 0.001). Median QRS-duration was 110 ms [95–146] without a correlation to the presence nor extent of midwall LGE. QRS-duration was moderately correlated with LV-dilation and mass (respectively r = 0.35, p < 0.001 and r = 0.30, p < 0.001). ConclusionIn DCM-patients, QRS-prolongation and septal midwall LGE are frequently present and often co-exist. However, they are not correlated. This suggests that the assessment of LGE-CMR has complementary value to ECG evaluation in the clinical assessment and risk stratification of DCM-patients.

A rare cause of intra-abdominal cysts: pancreatic cystic lymphangiomas.

Echenique et al. described a lymphangioma as a rare cystic neoplasm of the pancreas. We present a similar intra-abdominal lesion diagnosed by endoscopic ultrasound (EUS)-fine-needle aspiration (FNA) cytology.

Septal Late Gadolinium Enhancement and Arrhythmic Risk in Genetic and Acquired Non-Ischaemic Cardiomyopathies

In many genetic and acquired non-ischaemic cardiomyopathies (NICM) there have been frequent reports of involvement of the interventricular septum (IVS) by late gadolinium enhancement (LGE) at cardiac magnetic resonance (CMR). However, no studies have investigated the relationship between septal LGE and arrhythmias in different NICM subtypes. This study enrolled 103 patients with septal LGE at baseline CMR and different NICM: hypertrophic (n=29) or lamin A/C gene (LMNA)-associated (n=23) cardiomyopathy, and acute (n=30) or previous (n=21) myocarditis. During follow-up, the occurrences of malignant ventricular arrhythmias (MVA) and major bradyarrhythmias (BA) were evaluated. At 4.9±0.7 years of follow-up, the occurrence of MVA and major BA in genetic vs acquired NICM were 10 of 52 vs 12 of 51, and 10 of 52 vs 4 of 51, respectively (both p=n.s.). However, MVA occurred more frequently in LMNA-NICM (eight of 23 vs two of 29 hypertrophic, p=0.015) and in previous myocarditis (nine of 21 vs three of 30 acute, p=0.016), while major BAs were particularly common in LMNA-NICM patients only (nine of 23 vs one of 29 hypertrophic, p=0.003). Different patterns of septal LGE were consistently retrospectively identified at baseline CMR: junctional and limited to the base in 79.3% of uneventful hypertrophic NICM; extended and focally transmural in LMNA-NICM with follow-up arrhythmias (both p<0.05); transitory in patients with acute myocarditis, who, differently from the post-myocarditis ones, showed follow-up arrhythmias only in the presence of unmodified LGE at follow-up CMR (five of 13, p=0.009). Septal LGE was significantly associated with MVA at the 5-year follow-up in LMNA-NICM or previous myocarditis, and with major BA in LMNA-NICM only. These differences correlated with heterogeneous patterns of IVS LGE in different NICM.

4088Diagnostic specificity of triangular basal inferoseptal late gadolinium enhancement for identification of cardiac sarcoidosis

Abstract Background/Introduction Sarcoidosis, a multisystem disorder characterized by infiltration of noncaseating granulomas, can manifest as left ventricular (LV) dysfunction and fatal ventricular arrhythmias. The clinical diagnosis of cardiac sarcoidosis (CS) can be challenging and often requires multiple imaging modalities including cardiac magnetic resonance (CMR). The characterization of unique late gadolinium enhancement (LGE) patterns may assist in the diagnosis on CMR. Purpose We sought to examine the diagnostic value of inferoseptal triangular LGE for CS. Methods The retrospective cohort included 149 non-ischemic cardiomyopathy (NICM) patients referred to our hospital for a CMR from January 2012 to December 2018. Left ventricular LGE was identified in 86 patients (56.4±10.4 years, 84.9% male). Amongst them, 73 patients with septal LGE. We classified the various septal LGE patterns into four categories: (A) Mid-wall septal and basal inferoseptal triangular LGE; (B) Endocardial right ventricular (RV) septal LGE; (C) Basal inferoseptal triangular with endocardial RV septal LGE; (D) Mid-wall septal LGE (Figure). The diagnosis of sarcoidosis was confirmed by the Japanese Circulation Society/Japanese Society of Nuclear Cardiology guidelines. Results Individual diagnoses and imaging characteristics of non-ischemic cardiomyopathy types with septal LGE are summarized in the Table. LV ejection fraction, LV end-diastolic volume index (EDVI) and end-systolic volume index (ESVI) did not significantly differ between sarcoidosis and non-sarcoidosis patients. Pattern A and Pattern B were highly specific but insensitive (Specificity/Sensitivity- A: 98.4/8.3%, p=0.19; B: 95.1%/8.3%, p=0.64) for CS. The only pattern with statistically significantly diagnostic indices was pattern C: specificity of 100% and sensitivity of 58.3% (p&lt;0.001). Pattern D revealed both low specificity of 6.6% and sensitivity of 25% (p&lt;0.001). Imaging characteristics and diagnosis Septal LGE/Diagnosis Sarcoidosis Idiopathic Pulmonary hypertension Giant cell myocarditis Amyloidosis Systemic lupus erythematous Myeloproliferative neoplasm Large cell lymphoma Mid-wall septal and basal inferoseptal triangular LGE 1 1 0 0 0 0 0 0 Endocardial RV septal LGE 1 2 0 1 0 0 0 0 Basal inferoseptal triangular andendocardial RV septal LGE 7 0 0 0 0 0 0 0 Mid-wall septal LGE 3 50 3 0 1 1 1 1 Individual diagnosis and patterns of septal late gadolinium enhancement. Septal LGE patterns Conclusions The presence of basal inferoseptal triangular LGE pattern with endocardial RV involvement enables an accurate diagnosis of CS. The absence of this triangular septal LGE pattern, however, cannot exclude the diagnosis of CS. Acknowledgement/Funding Taipei Veterans General Hospital-National Yang-Ming University Excellent Physician Scientists Cultivation Program, No. 106-V-A-009

P595Characteristics of the right ventricle in patients with nonischemic dilated cardiomyopathy

Abstract Background In nonischemic dilated cardiomyopathy (DCM), diagnosis and prognosis is based on left ventricular function. Although concomitant right ventricular (RV) dysfunction is frequently observed, the underlying mechanism is currently not fully understood. Purpose We aimed to describe the characteristics of right ventricular function in DCM patients with cardiac magnetic resonance (CMR) imaging using cine and late-gadolinium enhancement (LGE) imaging. Methods Patients with DCM and left ventricular (LV) dysfunction (ejection fraction (EF) &lt;50%) on LGE-CMR were included prospectively. LV and RV volumes and function were quantified and RV systolic dysfunction was defined as RV ejection fraction (RVEF)&lt;45%. The presence and pattern of LGE were assessed visually and the extent was quantified using the full-width half maximum method. Septal midmyocardial LGE pattern was defined as midwall striae or hinge-point myocardial hyperenhancement. Moreover, left atrial (LA) volumes were calculated using the bi-plane area-length method. Results The study included 214 DCM patients (42% female, age 58±14 years) with a mean LVEF of 34±12% and RVEF of 46±12%. RV systolic dysfunction was present in 39% and was associated with the presence of septal midwall LGE (OR 1.96 (95% CI 1.09–3.54) p=0.026). In patients with RV dysfunction, LV dilation was more severe (LV end diastolic volume (EDV) 242±97mL vs. 212±58mL, p=0.011) and LVEF was lowere (26±12% vs. 39±8%, p&lt;0.001) (figure A). There was a weak correlation between septal LGE amount and LVEDV and RVEDV (respectively r=0.36, p=0.003 and r=0.35, p=0.005) In patients with RV dysfunction, left atrial volumes were enlarged (56±23mL/m2 vs. 46±14mL/m2, p&lt;0.001) and LA emptying fraction was moderately correlated to RVEF (figure B), also after exclusion of patients with a history of atrial fibrillation. RVEF in DCM patients Conclusion In DCM, reduced RVEF predominantly occurred in patients with a) LVEF lower than 30%, b) septal midwall enhancement, indicating progressive LV remodeling, c) LA dilation and d) LA dysfunction. This suggests that RV dysfunction in advanced DCM is drive by LV diastolic dysfunction resulting in increased afterload of the RV.