Unusual lesion in the splenium of the corpus callosum and coronavirus infectious disease-19.

Coronavirus infectious diseases (COVID-19) is an emerging infectious disease that has taken a strong grip on the entire global community. The diagnosis per se is straightforward; however, the disease seems to affect multiple organs. Cytokine-storm, increased thromboembolic state, deranged overall homeostasis and aggressive medical treatment can cause a variety of lesions in the central nervous system. Interpretation of brain imaging findings will require a thorough understanding of the clinical status of the patient and treatment being offered, keeping in mind the several ways in which the viral pathogen, severe acute respiratory syndrome coronavirus-2 may interact with brain tissue. We present differential diagnosis of a MRI identified solitary lesion in the splenium of the corpus callosum, in a COVID-19 positive patient with altered mental status.

Morphological MRI of knee cartilage: repeatability and reproducibility of damage evaluation and correlation with gross pathology examination.

OBJECTIVE: To assess the performance of a morphological evaluation, based on a clinically relevant magnetic resonance imaging (MRI) protocol, in scoring the severity of knee cartilage damage. Specifically, to evaluate the reproducibility, repeatability, and agreement of MRI evaluation with the gross pathology examination (GPE) of the tissue. METHODS: MRI of the knee was performed the day before surgery in 23 patients undergoing total knee arthroplasty. Osteochondral tissue resections were collected and chondral defects were scored by GPE according to a semi-quantitative scale. MR images were independently scored by four radiologists, who assessed the severity of chondral damage according to equivalent criteria. Inter- and intra-rater agreements of MRI evaluations were assessed. Correlation, precision, and accuracy metrics between MRI and GPE scores were calculated. RESULTS: Moderate to substantial inter-rater agreement in scoring cartilage damage by MRI was found among radiologists. Intra-rater agreement was higher than 96%. A significant positive monotonic correlation between GPE and MRI scores was observed for all radiologists, although higher correlation values were obtained by radiologists with expertise in musculoskeletal radiology and/or longer experience. The accuracy of MRI scores displayed a spatial pattern, characterized by lesion overestimation in the lateral condyle and underestimation in the medial condyle with respect to GPE. CONCLUSIONS: Evaluation of knee cartilage morphology by MRI is a reproducible and repeatable technique, which positively correlates with GPE. Clinical expertise in musculoskeletal radiology positively impacts the evaluation reliability. These findings may help to address limitations in MRI evaluation of knee chondral lesions, thus improving MRI assessment of knee cartilage. KEY POINTS: • MRI evaluation of knee cartilage shows moderate to strong correlation with gross pathology examination. • MRI evaluation overestimates cartilage damage in the lateral condyle and underestimates it in the medial condyle. • Education and experience of the radiologist play a role in MRI evaluation of knee chondral lesions.

Heterogeneous Enhancement Pattern in DCE-MRI Reveals the Morphology of Normal Lymph Nodes: An Experimental Study.

Purpose: To investigate the heterogeneous enhancement pattern in normal lymph nodes of healthy mice by different albumin-binding contrast agents. Methods: The enhancement of normal lymph nodes was assessed in mice by dynamic contrast-enhanced MRI (DCE-MRI) after the administration of two contrast agents characterized by different albumin-binding properties: gadopentetate dimeglumine (Gd-DTPA) and gadobenate dimeglumine (Gd-BOPTA). To take into account potential heterogeneities of the contrast uptake in the lymph nodes, k-means cluster analysis was performed on DCE-MRI data. Cluster spatial distribution was visually assessed. Statistical comparison among clusters and contrast agents was performed on semiquantitative parameters (AUC, wash-in rate, and wash-out rate) and on the relative size of the segmented clusters. Results: Cluster analysis of DCE-MRI data revealed at least two main clusters, localized in the outer portion and in the inner portion of each lymph node. With both contrast agents, AUC (p < 0.01) and wash-in (p < 0.05) rates were greater in the inner cluster, which also showed a steeper wash-out rate than the outer cluster (Gd-BOPTA, p < 0.01; Gd-DTPA, p=0.056). The size of the outer cluster was greater than that of the inner cluster by Gd-DTPA (p < 0.05) and Gd-BOPTA (p < 0.01). The enhancement pattern of Gd-DTPA was not significantly different from the enhancement pattern of Gd-BOPTA. Conclusion: DCE-MRI in normal lymph nodes shows a characteristic heterogeneous pattern, discriminating the periphery and the central portion of the lymph nodes. Such a pattern deserves to be investigated as a diagnostic marker for lymph node staging.

Multifaceted progressive neurotuberculosis in a single patient: from miliary tuberculomas to cortical venous infarct.

Neurotuberculosis is a potentially fatal disease which requires prompt diagnosis and immediate multidrug antitubercular treatment as per international guidelines. There is evidence that the bacterial spread can continue even during therapy at least in its initial stages. We monitored our patient not only with chest X-rays but with brain MRI during the first 6 weeks. To our surprise on serial MRI, during treatment, we found several new localization of the disease in a pauci-symptomatic patient. These included vessel wall inflammation (vasculitis), arachnoiditis and hypophysitis. At 4 weeks of treatment, the patient complained of dizziness and vomiting which were first dismissed as treatment side-effects but MRI revealed multiple cortical venous hemorrhagic infarcts. We report this case to emphasize the importance of neuroimaging even in case of the most subtle symptoms and that disease can continue to progress in the initial phase of treatment which may require additional therapeutic intervention.

Massive mitral annular calcification mimicking intracardiac mass: Multimodality approach to diagnosis.

The correct differential diagnosis of cardiac masses can be challenging and often carries important clinical implications. We present the case of a 78-year-old man with a cardiac mass of unclear etiology diagnosed on echocardiography. Using a multimodality approach with cardiac magnetic resonance and computed tomography, it was possible to define the real nature of the mass as composed of 2 voluminous calcifications of the mitral annulus.

Effect of Age on High T1 Signal Intensity of the Dentate Nucleus and Globus Pallidus in a Large Population Exposed to Gadodiamide.

OBJECTIVE: The purpose of this study was to assess the effect of age and number of previous injections of gadodiamide on the signal intensity of unenhanced T1-weighted (T1w) images of the dentate nucleus and globus pallidus in a large population. MATERIALS AND METHODS: A large, single-center retrospective population survey was designed and received institutional review board approval. Between January 2014 and December 2014, T1w signal intensity ratios were obtained from a large population of 2500 consecutive enhanced brain magnetic resonance imaging (MRI) scans. Of these, 1906 MRI scans of patients not previously exposed to any gadolinium (Gd)-based contrast agent were used as control group and were compared with 892 MRI scans of patients with documented prior exposure to intravenous gadodiamide. A quantitative study was conducted to assess the T1w signal intensity of dentate nucleus-to-pons (Dn/Po) and globus pallidus-to-thalamus (Gp/Th) ratios. Multiple regression analysis was used to test the effect of age, time delay, and number of previous Gd-based contrast agent injections as predictor variables of T1w signal intensity ratios. RESULTS: In the Gd-exposed patients, multivariate regression analysis showed age (ß = -0.285; P < 0.0001) and the number of previous injections of gadodiamide (ß = 0.224; P < 0.0001) to be powerful predictors of Dn/Po ratio. Similarly, age (ß = 0.269; P < 0.0001) and the number of previous injections of gadodiamide (ß = 0.127; P < 0.0001) predicted Gp/Th ratio. CONCLUSIONS: In this study, we confirm that the number of previous gadodiamide injections is a powerful predictor of the signal intensity increase of the Dn/Po and Gp/Th ratios on unenhanced T1w images and demonstrate that aging influences the T1 signal intensity of DN and GP in Gd-naïve and in Gd-exposed subjects.

Cardiac magnetic resonance in patients with acute cardiac injury and unobstructed coronary arteries.

AIM: To define the role of cardiac magnetic resonance (CMR) by analyzing a particular group of patients with suspected acute coronary syndrome (ACS) and normal coronary angiogram. METHODS: From January 2009 to December 2015, we examined 220 patients with clinical suspicion of ACS, Troponin elevation [the threshold used to define a positive Troponin T test (TnT) was 0.1 ng/mL] and no significant coronary disease at angiography (the patients were considered to have significant angiographic disease only a 50% stenosis was detected in any of their coronary arteries). The role of CMR with the late gadolinium enhancement was evaluated. RESULTS: CMR was performed to 190 patients (86%) of this group which reveals: Myocarditis in 90 patients (47%); apical ballooning (Tako-Tsubo syndrome) in 32 patients (17%); myocardial infarction (MI) in 40 patients (21%) and no clear diagnosis identified by CMR in 28 patients (15%). A comparison with previous studies was also made. Clinical and echocardiographic follow-ups were performed at 12 ± 2 mo and no major adverse cardiac events were revealed. CONCLUSION: There is a group of patients with clinical suspicion of ACS displaying normal coronary angiograms. CMR was demonstrated to be a valuable tool in the differential diagnosis evaluation of myocarditis, apical ballooning and MI.

Magnetic resonance imaging differential diagnosis of brainstem lesions in children.

Differential diagnosis of brainstem lesions, either isolated or in association with cerebellar and supra-tentorial lesions, can be challenging. Knowledge of the structural organization is crucial for the differential diagnosis and establishment of prognosis of pathologies with involvement of the brainstem. Familiarity with the location of the lesions in the brainstem is essential, especially in the pediatric population. Magnetic resonance imaging (MRI) is the most sensitive and specific imaging technique for diagnosing disorders of the posterior fossa and, particularly, the brainstem. High magnetic static field MRI allows detailed visualization of the morphology, signal intensity and metabolic content of the brainstem nuclei, together with visualization of the normal development and myelination. In this pictorial essay we review the brainstem pathology in pediatric patients and consider the MR imaging patterns that may help the radiologist to differentiate among vascular, toxico-metabolic, infective-inflammatory, degenerative and neoplastic processes. Helpful MR tips can guide the differential diagnosis: These include the location and morphology of lesions, the brainstem vascularization territories, gray and white matter distribution and tissue selective vulnerability.

Patterns of late gadolinium enhancement in Duchenne muscular dystrophy carriers.

BACKGROUND: This study was designed to assess whether cardiovascular magnetic resonance imaging (CMR) in Duchenne muscular dystrophy carriers (DMDc) may index any cell milieu elements of LV dysfunction and whether this cardiac phenotype may be related to genotype. The null hypothesis was that myocardial fibrosis, assessed by late gadolinium enhancement (LGE), might be similarly accounted for in DMDc and gender and age-matched controls. METHODS: Thirty DMDc patients had CMR and genotyping with 37 gender and age-matched controls. Systolic and diastolic LV function was assessed by 2D-echocardiography. RESULTS: Absolute and percent LGE were higher in muscular symptomatic (sym) than asymptomatic (asy) DMDc (1.77 ± 0.27 vs 0.76 ± 0.17 ml; F = 19.6, p < 0.0001 and 1.86 ± 0.26% vs 0.68 ± 0.17%, F = 22.1, p < 0.0001, respectively). There was no correlation between LGE and age. LGE was seen most frequently in segments 5 and 6; segment 5 was involved in all asy-DMDc. Subepicardial LGE predominated, compared to the mid-myocardial one (11 out of 14 DMDc). LGE was absent in the subendocardium. No correlations were seen between genotyping (type of mutation, gene region and protein domain), confined to the exon's study, and cardiac phenotype. CONCLUSIONS: A typical myocardial LGE-pattern location (LV segments 5 and 6) was a common finding in DMDc. LGE was more frequently subepicardial plus midmyocardial in sym-DMDc, with normal LV systolic and diastolic function. No genotype-phenothype correlation was found.

Mammographic and ultrasonographic comparison between intraoperative radiotherapy (IORT) and conventional external radiotherapy (RT) in limited-stage breast cancer, conservatively treated.

OBJECTIVE: Assess mammographic and echographic modifications in mild cases of breast cancer (suitable for conservative surgery) after intraoperatory radio treatment (IORT) as opposed to conventional post-operative radiotherapy (RT). MATERIALS AND METHODS: We report data from 45 patients in each group (IORT and RT). All patients were examined using the same mammographic and ecographic equipment at 6, 12 and 24 months after treatment. We focused on structural alterations, edema and others, and quantified them using pre-established (unbiased) protocols. Both patient examination and subsequent assessment of the results were performed by radiologists with exepertise in breast cancer evaluation. RESULTS: At 6 months, IORT patients showed slightly more pronounced structural distortions and oedema than RT patients; these differences became more apparent at 12 months, with the addition of fat necrosis and/or calcifications. These alterations were evident and consistent under both mammographic and ecographic examination, and became even more pronounced at 24 months. At this stage, RT patients showed minimal alterations of the tissue (apart from normal post-surgical scarring), whereas IORT patients showed virtually no improvement over the preceding 12-month period. CONCLUSION: We show radiological alterations in post-operative breast cancer are significantly more pronounced in patients treated with IORT as opposed to RT.

The role of multidetector CT in the evaluation of the left atrium and pulmonary veins anatomy before and after radio-frequency catheter ablation for atrial fibrillation. Preliminary results and work in progress. Technical note.

Radio-frequency catheter ablation (RFCA) of the distal pulmonary veins is increasingly being used to treat recurrent or refractory atrial fibrillation that doesn't respond to pharmacologic therapy or cardioversion. Successful RFCA of atrial fibrillation depends on the pre-procedural understanding of the complex anatomy of the distal pulmonary veins and the left atrium. Aim of this paper is to describe the technical main features that characterise the multidetector helical computed tomography in the evaluation of this anatomic region before and after RFCA procedure. The 3D post-processing techniques useful for pre-RFCA planning are straightforward.

Advantages and limits of percutaneous breast core biopsy with Mammotome and stereotactic equipment in upright seated patient.

PURPOSE: To confirm the diagnostic accuracy of percutaneous core breast biopsy with Mammotome and stereotactic equipment in upright seated patients, and to compare results from this method with those obtained using the dedicated unit with prone table. MATERIALS AND METHODS: We analysed 72 microbioptic samples from 69 upright seated patients. These samples were obtained in the course of mammographies assisted by digital stereotactic equipment (Diamond Delta32 General Electric Medical System/Instrumen-tarium), and further equipped with a lateral arm to support the Mammotone probe. We studied the following lesions: 57 cases of isolated microcalcification clusters, 12 masses with microcalcification and three cases of plain masses. We describe in detail the various phases of our 30-minute long microbiopsy procedure. All 72 samples were extracted without problems. Only in one case a large haematoma emerged, but quickly disappeared. RESULTS: We were able to characterise the histology of the lesions in all our samples: in 39/72 cases they were identified as benign, 28 were classified as malignant, and the remaining 5 as atypia. In the 39 lesions identified as benign, the microbiopsy procedure could be carried out without surgical biopsy - consequently, these patients were available for routine follow-up exams, which confirmed the benign nature of their lesions. Our identification of the 28 malignant lesions was confirmed by surgical biopsy. The microbiopsy finding and the histological result did not agree in only two cases. The 5 cases with atypical ductal hyperplasia showed no neoplastic alteration following surgical biopsy. In our personal experience, core biopsy with Mammotome achieved a high diagnostic accuracy. CONCLUSIONS: After careful analysis of the results obtained using Mammotome in upright seated patients with stereotactic equipment, we can confirm the diagnostic accuracy of this procedure in mammography alterations not visible in sonography. In agreement with previous studies, we also confirm that the diagnostic accuracy of this approach, as well as possible complications deriving from it, do not depend on the position of the patient.