Mi-Young Jeung

Tacrolimus-Associated Posterior Reversible Encephalopathy Syndrome after Solid Organ Transplantation

Tacrolimus (TAC) is an immunosuppressant drug discovered in 1984 by Fujisawa Pharmaceutical Co., Ltd. This drug belongs to the group of calcineurin inhibitors, which has been proven highly effective in preventing acute rejection after transplantation of solid organs. However, neurotoxicity and nephrotoxicity are its major adverse effects. Posterior reversible encephalopathy syndrome (PRES) is the most severe and dramatic consequence of calcineurin inhibitor neurotoxicity. It was initially described by Hinchey et al. in 1996 [N Engl J Med 1996;334:494–450]. Patients typically present with altered mental status, headache, focal neurological deficits, visual disturbances, and seizures. Magnetic resonance imaging is the most sensitive imaging test to detect this. With the more deep-going studies done recently, we have learnt more about this entity. It was noted that this syndrome is frequently reversible, rarely limited to the posterior regions of the brain, and often located in gray matter and cortex as well as in white matter. Therefore, in this review, the focus is on the current understanding of clinical recognition, pathogenesis, neuroimaging and management of TAC-associated PRES after solid organ transplantation.

Myocardial Tagging with MR Imaging: Overview of Normal and Pathologic Findings

Magnetic resonance tagging is used to evaluate the dynamic deformation of lines or grids superimposed on the myocardium during the cardiac cycle. From these data, a specific postprocessing procedure provides two kinds of metrics: (a) three orthogonal components of myocardial motion (longitudinal, circumferential, and radial), and (b) rotation and torsion. Strain expresses the local myocardial deformation and is prone to important physiologic heterogeneities. Peak systolic strain is in the range of -15% to -20% for the longitudinal and circumferential components (fiber shortening) and 30%-40% for the radial component (wall thickening). The helical arrangement of myofibers that run in opposite directions at the epicardium and endocardium explains systolic twist (~15°). This torsion may be enhanced during the early stage of several diseases (eg, hypertrophic cardiomyopathy) or in heart failure with a normal left ventricular ejection fraction. Strain is generally impaired in ischemic heart disease and cardiomyopathy, but the most diagnostically significant finding is the early identification of contractile dysfunction on the basis of longitudinal and circumferential strain reduction in patients with apparently preserved systolic function. Thus, strain impairment appears to be a sensitive and promising marker of subclinical disease, with the potential for improving patient management.

Native T1 Mapping of the Heart – A Pictorial Review

T1 mapping is now a clinically feasible method, providing pixel-wise quantification of the cardiac structures T1 values. Beyond focal lesions, well depicted by late gadolinium enhancement sequences, it has become possible to discriminate diffuse myocardial alterations, previously not assessable by noninvasive means. The strength of this method includes the high reproducibility and immediate clinical applicability, even without the use of contrast media injection (native or pre-contrast T1). The two most important determinants of native T1 augmentation are (1) edema related to tissue water increase (recent infarction or inflammation) and (2) interstitial space increase related to fibrosis (infarction scar, cardiomyopathy) or to amyloidosis. Conversely, lipid (Anderson–Fabry) or iron overload diseases are responsible for T1 reduction. In this pictorial review, the main features provided by native T1 mapping are discussed and illustrated, with a special focus on the awaited clinical purpose of this unique, promising new method.

Correlation between high-resolution computed tomography findings and lung function in pulmonary langerhans cell histiocytosis

Background: Pulmonary Langerhans cell histiocytosis (PLCH) is an uncommon interstitial lung disease which can lead to serious respiratory failure. The correlation between high-resolution computed tomography (HRCT) findings and lung function have not been studied in depth. Objectives: To assess the relationship between HRCT findings and lung function in PLCH. Methods: Since HRCT abnormalities in PLCH consist mainly of nodular opacities and cystic abnormalities, we determined semiquantitative scores of nodular profusion and cystic extent. We therefore assessed the relationship between HRCT abnormalities on one hand and lung function and gas exchange parameters on the other, in patients with PLCH. Results: In our series of 26 consecutive patients, we found no significant correlation between the score of nodular profusion and lung function or gas exchange parameters. The score of cystic extent showed a quite strong and significant correlation with FEV1/FVC (r = –0.62; p = 0.01), but also with PaO2 (r = –0.69; p = 0.001) and carbon monoxide diffusing capacity (r = –0.60; p < 0.01). Furthermore, the patients with a predominant cystic pattern (n = 7) had the highest grade of dyspnea on exertion (p = 0.004), the lowest FEV1/FVC ratio (p = 0.02) and the lowest PaO2 (p = 0.02) compared to patients with a predominant nodular (n = 12) or a mixed pattern (n = 7). Conclusions: We conclude that in PLCH, the cystic extent on HRCT, but not the nodular profusion, correlates significantly with lung function abnormalities and impairment of gas exchange.

Left Ventricular Involvement in Arrhythmogenic Right Ventricular Cardiomyopathy – A Cardiac Magnetic Resonance Imaging Study

Background Few studies evaluated left ventricular (LV) involvement in arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). The aim of this study is to determine the frequency, clinical presentation, and pattern of LV involvement in ARVD/C (LV-ARVD/C). Methods We retrospectively evaluated the cardiac magnetic resonance (CMR) in 202 patients referred between 2008 and 2012 to our institution, and we determined the presence or the absence of CMR criteria in the revised task force criteria 2010 for the diagnosis of ARVD/C. A total of 21 patients were diagnosed with ARVD/C according to the revised task force criteria 2010. All included patients had no previous history of myocarditis, acute coronary syndrome, or any other cardiac disease that could interfere with the interpretations of structural abnormalities. The LV involvement in ARVD/C was defined by the presence of one or more of the following criteria: LV end-diastolic volume (LVEDV; >95 mL/m2), LV ejection fraction (LVEF; <55%), LV late enhancement of gadolinium (LVLE) in a non-ischemic pattern, and LV wall motion abnormalities (WMAs). In the follow-up for the occurrence of cardiac death, ventricular tachycardia (VT) was obtained at a mean of 31 ± 20.6 months. Results A total of 21 patients had ARVD/C. The median age was 48 (33-63) years. In all, 11 patients (52.4%) had LV-ARVD/C. The demographic characteristics of patients with or without LV were similar. There was a higher frequency of left bundle-branch block (LBBB) VT morphology in ARVD/C (P = 0.04). In CMR, regional WMAs of right ventricle (RV) and RV ejection fraction (RVEF; <45%) were strongly correlated with LV-WMAs (r = 0.72, P = 0.02, r = 0.75, P = 0.02, respectively). RV late enhancement of gadolinium (RVLE) was associated with LV-WMs and LVLE (r = 0.7, P = 0.03; r = 0.8, P = 0.006). LVLE was associated with LV-WMAs, LVEF, and LVEDV (r = 0.9, P = 0.001; r = 0.8, P = 0.001; r = 0.8, P = 0.01). Conclusion LV involvement in ARVD/C is common and frequently associated with moderate to severe right ventricular (RV) abnormalities. The impact of LV involvement in ARVD/C on the prognosis needs further investigations.

Quantification of left ventricular dyssynchrony in patients with systolic dysfunction: A comparison of circumferential strain MR‐tagging metrics

To define which circumferential strain MR‐tagging metrics of left intraventricular dyssynchrony better identifies patients with systolic dysfunction against control subjects.

Lung Transplantation for Advanced Cystic Lung Disease Due to Nonamyloid Kappa Light Chain Deposits

RATIONALE Cystic lung light chain deposition disease (LCDD) is a severe and rare form of nonamyloid kappa light chain deposits localized in the lung, potentially leading to end-stage respiratory insufficiency. OBJECTIVES To assess the outcome after lung transplantation (LT) in this setting with particular attention to disease recurrence. METHODS We conducted a retrospective multicenter study of seven patients who underwent LT for cystic lung LCDD in France between September 1992 and June 2012 in five centers. MEASUREMENTS AND MAIN RESULTS In total, five females and two males (mean age, 39.1 ± 5.3 yr) underwent one single LT or seven double LT (one retransplantation). Before LT, the patients showed a constant obstructive ventilatory pattern with low carbon monoxide diffusing capacity and resting hypoxemia. Lung computed tomography revealed widespread cysts with occasional micronodulations. No extrapulmonary disease or plasma cell neoplasm was detected. The serum-free kappa/lambda light chain ratio was increased in three cases. The median follow-up after LT was 56 months (range, 1-110 mo). Kaplan-Meier survival was 85.7, 85.7, and 64.3% at 1, 3, and 5 years, respectively. Three patients died from multiorgan failure (n = 1), chronic rejection (n = 1), and breast cancer (n = 1) at 23 days, 56 months, and 96 months, respectively. At the end of follow-up, no patients showed recurrence on imaging or histopathology. CONCLUSIONS This small case series confirms that cystic lung LCDD is a severe disease limited to the lung, affecting mostly young females. LT appears to be a good therapeutic option allowing for satisfactory long-term survival. We found no evidence of recurrence of the disease after LT.

Diagnostic performance of ultra-low-dose computed tomography for detecting asbestos-related pleuropulmonary diseases: prospective study in a screening setting

Objective To evaluate the diagnostic performance of Ultra-Low-Dose Chest CT (ULD CT) for the detection of any asbestos-related lesions (primary endpoint) and specific asbestos-related abnormalities, i.e. non-calcified and calcified pleural plaques, diffuse pleural thickening, asbestosis and significant lung nodules (secondary endpoints). Material and Methods 55 male patients (55.7±8.1 years old) with occupational asbestos exposure for at least 15 years and where CT screening was indicated were prospectively included. They all underwent a standard unenhanced chest CT (120kV, automated tube current modulation), considered as the reference, and an ULD CT (135kV, 10mA), both with iterative reconstruction. Two chest radiologists independently and blindly read the examinations, following a detailed protocol. Sensitivity, specificity, positive predictive value, negative predictive value, accuracy and error rate of ULD CT were calculated using the exact method of Pearson with a confidence interval of 95%. Results Radiation dose was 17.9±1.2mGy.cm (0.25mSv) for the ULD-CT versus 288.8 ±151mGy.cm (4mSv); p <2.2e-16. Prevalence of abnormalities was 20%. The ULD CT’s diagnostic performance in joint reading was high for the primary endpoint (sensitivity = 90.9%, specificity = 100%, positive predictive value = 100%, negative predictive value = 97.8%), high for lung nodules, diffuse pleural thickening and calcified pleural plaques (sensitivity, specificity, PPV and NPV = 100%) and fair for asbestosis (sensitivity = 75%, specificity = 100%, PPV = 00%, NPV = 98.1%). Intra-reader accuracy between the ULD CT and the reference CT for the primary endpoint was 98% for the senior and 100% for the junior radiologist. Inter-reader agreement for the primary endpoint was almost perfect (Cohen’s Kappa of 0.81). Conclusion ULD CT in the screening of asbestos exposure related diseases has 90.9% sensitivity and 100% specificity, and could therefore be proposed as a first line examination.

Idiopathic myocardial calcification: Insights from multimodality imaging

Article history: Received 3 June 2016 Accepted 9 July 2016 Available online 11 July 2016 T1 and T2 mapping in mass revealed low T1 (370 ms vs 1050 ms in the remote LV lateral myocardium) and T2 values (43 ms vs 50 ms in the remote LV lateral myocardium) (Fig. 1C, D, E). Contrast technique showed no late gadolinium enhancement (LGE) in themass itself except at its periphery (Fig. 1F). Therewas apical trans-mural LGE, but no LGE of ischemic or non-ischemic distribution in the over-all IVS wall (Fig. 1F).

Multimodality Imaging Diagnostic Approach of Systemic‐to‐Pulmonary Vein Fistulae

A 26‐year‐old man with a history of bilateral lung transplantation for pulmonary cystic fibrosis 6 months before was admitted in our institution for acute heart failure. Cardiac magnetic resonance imaging (CMR) showed an increased aortic output, as aortic flow assessed by velocity mapping was twofold the pulmonary flow, an occluded superior vena cava (SVC), and enlarged azygos vein. A systemic‐to‐pulmonary vein fistula (SAPVF) was suspected. The selective angiography showed numerous fistulae between intercostals, thyro‐cervical, internal mammary arteries and pulmonary veins. The thoracic CT performed before the CMR, which was initially considered as normal, showed well these arteriovenous fistulae after 3D MIP reconstruction. This particular observation highlights the great value of multimodality imaging for the diagnosis of this rare pathology. The MR velocity mapping is a noninvasive imaging technique of great interest to guide the diagnosis of arteriovenous fistulae, and further indicating more invasive complementary imaging modalities like selective arterial angiography.