Brain magnetic resonance imaging radiomics features associated with hepatic encephalopathy in adult cirrhotic patients.

PURPOSE: Hepatic encephalopathy (HE) is a potential complication of cirrhosis. Magnetic resonance imaging (MRI) may demonstrate hyperintense T1 signal in the globi pallidi. The purpose of this study was to evaluate the performance of MRI-based radiomic features for diagnosing and grading chronic HE in adult patients affected by cirrhosis. METHODS: Adult patients with and without cirrhosis underwent brain MRI with identical imaging protocol on a 3T scanner. Patients without history of chronic liver disease were the control population. HE grading was based on underlying liver disease, severity of clinical manifestation, and number of encephalopathic episodes. Texture analysis was performed on axial T1-weighted images on bilateral lentiform nuclei at the level of the foramina of Monro. Diagnostic performance of texture analysis for the diagnosis and grading of HE was assessed by calculating the area under the receiver operating characteristics (AUROC) with 95% confidence interval (CI). RESULTS: The final study population consisted of 124 patients, 70 cirrhotic patients, and 54 non-cirrhotic controls. Thirty-eight patients had history of HE with 22 having an HE grade > 1. The radiomic features predicted the presence of HE with an AUROC of 0.82 (95% CI: 0.73, 0.90; P < .0001; 82% sensitivity, 66% specificity). Radiomic features predicted grade 1 HE (AUROC 0.75; 95% CI: 0.61, 0.89; P < .0001; 94% sensitivity, 60% specificity) and grade ≥ 2 HE (AUROC 0.82; 95% CI: 0.71, 0.93; P < .0001, 95% sensitivity, 57% specificity). CONCLUSION: In cirrhotic patients, MR radiomic is effective in predicting the presence of chronic HE and in grading its severity.

Multiple sclerosis: prevalence of the 'central vein' sign in white matter lesions on gadolinium-enhanced susceptibility-weighted images.

AIMS: To evaluate prospectively whether an intravenous gadolinium injection could improve the detection of the central vein sign on susceptibility-weighted imaging sequences obtained with a 1.5 T magnetic resonance scanner in patients with multiple sclerosis compared to unenhanced susceptibility-weighted images. MATERIALS AND METHODS: This prospective, institution review board-approved study included 19 patients affected by multiple sclerosis (six men; 13 women; mean age 40.8 years, range 20-74 years). Patients had the relapsing-remitting clinical subtype in 95% of cases, and only one (5%) patient had the primary progressive clinical subtype of multiple sclerosis. T2-weighted images, fluid-attenuated inversion recovery images, unenhanced and contrast-enhanced susceptibility-weighted images were evaluated in consensus by two neuroradiologists for the presence of the central vein sign. The readers were blinded to magnetic resonance imaging reports, clinical information, the presence and the localisation of focal hyperintense white matter lesions. Any discordance between readers was resolved through a joint review of the recorded images with an additional neuroradiologist. RESULTS: A total of 317 multiple sclerosis lesions were analysed. The central vein sign had a higher prevalence detection rate on gadolinium-enhanced susceptibility-weighted images (272 of 317 lesions, 86%) compared to unenhanced susceptibility-weighted images (172 of 317 lesions, 54%). CONCLUSION: Gadolinium-enhanced susceptibility-weighted imaging improves the detection rate of the central vein sign in multiple sclerosis lesions.

A rare case of ruptured aneurysm of the paramedian artery of Percheron.

Introduction The artery of Percheron is a rare anatomic variant supplying bilateral medial thalamic nuclei and a variable portion of the rostral part of midbrain. Case report A 48-year-old female with massive subarachnoid hemorrhage due to a ruptured aneurysm of the paramedian artery of Percheron presented to the emergency room. Because of significant risk of recurrent intracranial hemorrhage, it was decided to proceed with endovascular embolization of the aneurysm. The patient was ultimately sent to a rehabilitation center and her presenting neurologic deficits showed significant improvements in the weeks following endovascular embolization treatment. Discussion The paramedian artery of Percheron is a rare anatomic variant and subarachnoid hemorrhage due to aneurysm of this artery is exceedingly rare. This case underlines the importance of a correct evaluation of cerebral arterial anatomy in order to choose the best endovascular therapeutic approach, reduce complications, and optimize patient outcome.

Diagnostic performance of reformatted isotropic thin-section helical CT images in the detection of superior semicircular canal dehiscence.

Purpose The purpose of this article is to assess the diagnostic performance of computed tomography (CT) reformatted images for detection of superior semicircular canal (SSC) dehiscence. Material and methods Forty-two patients, with sound- and/or pressure-induced vestibular symptoms, and 42 control participants underwent helical CT examination with a highly collimated beam (0.5 mm). Reformatted images of the vestibular labyrinth were obtained in the standard axial and coronal planes (group A images), and in a plane parallel and perpendicular to the SSC (group B images). Diagnostic performance obtained by evaluating the group A images alone and the group B images alone was analyzed by using the area under the receiver operating characteristic curve (AUC). Results The diagnostic performance of group A images was AUC = 0.929 with an overall accuracy of 92.9%. The diagnostic performance of group B images was AUC = 0.988 with an overall accuracy of 98.8%. The evaluation of group B images alone showed an improved diagnostic performance over the group A images alone. Conclusion Thin-section 0.5-mm collimation CT with reformatted images oriented in the plane parallel and perpendicular to the SSC improves diagnostic accuracy in assessing for SSC dehiscence in comparison to CT images with reconstructions limited to traditional axial and coronal planes.

Assessment of cerebral microbleeds by susceptibility-weighted imaging in Alzheimer's disease patients: A neuroimaging biomarker of the disease.

Purpose The objective of this study was to correlate the presence and distribution of cerebral microbleeds in Alzheimer's disease patients with cerebrospinal fluid biomarkers (amyloid-beta and phosphorylated tau 181 protein levels) and cognitive decline by using susceptibility-weighted imaging magnetic resonance sequences at 1.5 T. Material and methods Fifty-four consecutive Alzheimer's disease patients underwent brain magnetic resonance imaging at 1.5 T to assess the presence and distribution of cerebral microbleeds on susceptibility-weighted imaging images. The images were analyzed in consensus by two neuroradiologists, each with at least 10 years' experience. Dementia severity was assessed with the Mini-Mental State Examination score. A multiple regression analysis was performed to assess the associations between the number and location of cerebral microbleed lesions with the age, sex, duration of the disease, cerebrospinal fluid amyloid-beta and phosphorylated tau 181 protein levels, and cognitive functions. Results A total of 296 microbleeds were observed in 54 patients; 38 patients (70.4%) had lobar distribution, 13 patients (24.1%) had non-lobar distribution, and the remaining three patients (5.6%) had mixed distribution, demonstrating that Alzheimer's disease patients present mainly a lobar distribution of cerebral microbleeds. The age and the duration of the disease were correlated with the number of lobar cerebral microbleeds ( P < 0.001). Cerebrospinal fluid amyloid-beta, phosphorylated tau 181 protein levels, and cognitive decline were correlated with the number of lobar cerebral microbleeds in Alzheimer's disease patients ( P < 0.001). Conclusion Lobar distribution of cerebral microbleeds is associated with Alzheimer's disease and the number of lobar cerebral microbleeds directly correlates with cerebrospinal fluid amyloid-beta and phosphorylated tau 181 protein levels and with the cognitive decline of Alzheimer's disease patients.

Reductions in High-End Imaging Utilization With Radiology Review and Consultation.

Following the uptake of value-based purchasing in concert with health care reform in the United States, providers, insurers, and patients are looking for ways to reduce excessive, dangerous, and/or inappropriate high-end imaging utilization (HEIU). Inappropriate HEIU is associated with patient safety risks due to unnecessary exposure to radiation, misappropriation of scarce equipment resources and staff, complications to clinical care, and needless, excessive costs for the patient, hospital, and payer. This paper presents a cost-effective radiology-initiated improvement program piloted in the Christiana Hospital Coordinated Care Network. The pilot demonstrated the effectiveness of regulating high-end imaging orders through radiologists' review of requests of the order as part of the consult process. Over the 2014-2015 fiscal year, 2,177 high-end imaging orders were reviewed by 26 radiologists for approval, rejection, or recommendation of an alternate examination. Of the orders, 86.7% (1887) were approved, 4.0% (87) were rejected, and 9.3% (203) received recommendation for an alternate examination. Based on improved patient safety, cost savings, and appropriate resource use, these findings suggest that radiologists' review can effectively reduce excessive HEIU. This method, with an appropriate algorithm to assist with handling a larger volume of orders, would be ideal to implement systemwide to manage HEIU cost efficiency, simultaneously providing radiologists with more control in their area of expertise and positively impacting quality, safety, and value-based purchasing goals.

Usefulness of quantitative peritumoural perfusion and proton spectroscopic magnetic resonance imaging evaluation in differentiating brain gliomas from solitary brain metastases.

OBJECTIVES: The purpose of our study was to evaluate whether peritumoural perfusion weighted and proton spectroscopic magnetic resonance imaging can be used in differentiating between primary gliomas and solitary metastases. METHODS: Ten low-grade gliomas, eight high-grade gliomas and 10 metastases were prospectively evaluated with magnetic resonance imaging, dynamic susceptibility contrast enhanced perfusion imaging and single-voxel proton magnetic resonance spectroscopy before surgical resection or stereotactic biopsy. Maximal relative cerebral blood volume values were calculated drawing three regions of interest of 2 cm(2) in the non-enhancing peritumoural areas. Maximal relative cerebral blood volume values were normalised to that of contralateral normal-appearing white matter. Maximal choline/creatine ratios were calculated from three voxels of 10 cm(3) placed in the peritumoural areas defined as non-enhancing peritumoural white matter surrounding the tumour. The tumour grade presumed with these values was compared to histopathological grading. Differences in the study parameters between groups were assessed using the Mann-Whitney test. A receiver operating characteristic analysis was performed to determine cut-off values. RESULTS: A clear relative cerebral blood volume cut-off value of 1.88 was detected for differentiating low-grade gliomas from high-grade gliomas. A clear relative cerebral blood volume cut-off value of 1.20 was detected for differentiation of metastases from gliomas. The differences in the choline/creatine ratios in the peritumoural regions of high-grade gliomas and of solitary metastasis were statistically significant (P < 0.001) but a clear cut-off value was not found. CONCLUSION: Our preliminary data support the hypothesis that peritumoural perfusion-weighted imaging can assist in preoperative differentiation between a glioma and a solitary metastasis.

Ischaemic stroke induced by neurocysticerosis, presenting as a clinical and radiological dilemma.

Neurocysticercosis (NCC) is a central nervous system parasitic infection with various clinical presentations, rarely manifesting as an acute stroke. The radiological appearance of this disease entity may be non-specific, at times mimicking an intracranial neoplasm. Early diagnosis requires a high index of suspicion. Serological testing is helpful and, if utilized early, can reduce the morbidity associated with invasive diagnostic techniques. We describe a case of a 32-year-old previously healthy male who presented with neurological deficits. A cystic lesion in the right sylvian cistern was noted, initially identified as a benign arachnoid cyst. The patient's symptoms rapidly progressed to an acute stroke. Follow-up imaging including an MRI of the brain demonstrated a right middle cerebral artery territory infarct adjacent to the cystic lesion, which had been diagnosed as an arachnoid cyst on an initial CT scan. Appearance of the cystic lesion on MRI, however, was concerning for a brain neoplasm or an abscess. Given the contiguity of the cystic mass to the right middle cerebral artery, it was suggested that the mass was the likely aetiology of the patient's symptoms. A stereotactic biopsy of the cystic lesion was performed and revealed it to be NCC. The hospital course was complicated by intracranial hypertension and cerebral oedema requiring craniectomy. Our case highlights the importance of considering NCC in the differential diagnosis of stroke in patients coming from endemic regions, especially in younger patients lacking the usual risk factors for cerebrovascular disease.

Normative inner ear volumetric measurements.

In the current study, we attempted to determine normative inner ear volumetric measurements generated from three-dimensional computed tomography (CT) images. In addition, we investigated a correlation between the axial length and the volume of the labyrinth and discussed clinical outcomes of this correlation. Amira 5.2.2 software was used to create three-dimensional isosurface images of the human labyrinth using two-dimensional CT images from 35 anatomically normal patients. With the three-dimensional labyrinths, complete dimensional analysis was performed to gain insight into both the volume and the greatest axial length of the inner ear. Paired t test and Pearson correlation were used. Our volume of the inner ear inquiry reported a mean volume of 221.5 with SD of 24.3 µL (0.228 µL for males and 0.218 µL for females). The length showed a mean of 1.713 cm with SD of 0.064 cm (1.753 cm for males and 1.695 cm for females). The length was used to estimate the volume, and the estimates were within 10% of the measured volume 74.3% of the time. Normative volumetric measurements of the inner ear can be obtained by using three-dimensional CT Imaging by Amira 5.2.2 software. There was a statistically significant positive correlation between the axial length of the labyrinth and the volume of the labyrinth. The axial length of the labyrinth could be used to estimate the volume of the labyrinth, which may be clinically important to estimate the concentration of the drug distributed in the inner ear.