Atypical Imaging Research Articles

Clinical features and reasons for missed diagnosis of allergic bronchopulmonary aspergillosis

Objective: To summarize the clinical features of allergic bronchopulmonary aspergillosis (ABPA) and analyze the common causes of missed diagnosis. Methods: The clinical data of patients with ABPA who were admitted into Qilu Hospital of Shandong University from October 2014 to November 2017 were retrospectively analyzed, including baseline data, eosinophil count in peripheral blood, serum total IgE, A. fumigates-specific antibody (sIgE, sIgG and sIgM), pulmonary function tests and chest CT, etc. Then the correlations between serum total IgE, sIgE and forced expiratory volume in one second (FEV1) as percentage of predicted value (FEV1%pred) was conducted, as well as that between serum total IgE, sIgE and FEV1/forced vital capacity (FEV1/FVC). The clinical features of the patients were summarized and the causes of missed diagnosis were analyzed. Results: There were 46 patients with ABPA (21 males and 25 females, 48.3±13.2 years old) in total. Only 2 cases (4.3%) were diagnosed after the first symptom onset, and 44 cases (95.7%) were treated repeatedly for many years before being diagnosed. The misdiagnoses were asthma (26 cases, 56.5%), bronchiectasis (13 cases, 28.3%), pneumonia (4 cases, 8.7%), pulmonary tuberculosis (3 cases, 6.5%), and lung cancer (4 cases, 8.7%). Common symptoms of ABPA included cough, expectoration, wheezing, chest tightness, fever, weight loss, chest pain, etc. Peripheral blood eosinophil count increased in 37 patients (80.4%). Serum total IgE in 37 patients (80.4%) were higher than 1 000 U/ml, and 9 cases (19.6%) were less than 1 000 U/ml. The positive rate of sIgE, sIgG and sIgM was 100.0%, 89.1% and 54.3%, respectively. All patients underwent pulmonary function tests and 35 cases (76.1%) had obstructive ventilation dysfunction, 5 cases (10.9%) with mixed ventilation dysfunction, 5 cases (10.9%) were normal and 1 case (2.2%) with restrictive ventilation dysfunction. All patients underwent Chest CT examination, 28 cases (60.9%) showed bronchiectasis, 8 cases (17.4%) manifested mucus plugs (among them, 4 cases with high-attenuation mucus) and 10 cases (21.7%) had other atypical imaging. Serum total IgE and sIgE had no correlations with FEV1%pred and FEV1/FVC. Conclusions: ABPA is characterized by recurrent episodes of wheezing, fleeting pulmonary opacities and bronchiectasis. The main reasons of misdiagnosis in ABPA patients were: atypical symptoms, variety of predisposing diseases, early atypical imaging changes, limitations and misunderstandings of screening indicators, interference with tumor markers, and the presence of pulmonary aspergillus overlap syndrome. The severity of asthma attacks is not related to the degree of fungal sensitization.

A case report of an immunocompetent patient with Coccidioides meningoencephalitis with atypical brain magnetic resonance imaging findings during a 1 year follow-up

Coccidioides meningoencephalitis is a central nervous system (CNS) fungal infection withCoccidioides species which can lead to various CNS complications, such as hydrocephalus,vasculitis, and stroke. Most cases reported with Coccidioides meningoencephalitis were inimmunocompromised patients, and the radiologic characteristics on this condition are not wellestablished. Here we report a case of Coccidioides meningoencephalitis in an immunocompetentpatient with one-year follow-up brain magnetic resonance image (MRI) studies after successfultreatment with antifungal drugs. The MRI demonstrated subcortical parenchymal lesions,selectively involving the white matter, and persistent meningeal enhancement.

Papillary renal cell carcinoma in contrast-enhanced ultrasound (CEUS) - A diagnostic performance study.

Renal cell carcinomas (RCC) represent a heterogeneous group of hypo- and hypervascularized malignancies. Using contrast-enhanced ultrasound (CEUS) specific imaging features of clear cell (ccRCC), papillary (pRCC) and chromophobe RCC (chRCC) subtypes have been demonstrated. However, some RCCs show atypical imaging features making it difficult to distinguish between the subtypes. This study was performed to evaluate the observed enhancement features of pRCC in CEUS and to assess the sensitivity in the diagnosis of suspected renal malignancies in a 10 year retrospective analysis at our institution. The study population consisted of 60 patients with histologically confirmed pRCC. All patients underwent CEUS imaging between 2005 and 2015 as part of their diagnostic workup. In 45 out of 60 (75%) cases the examined pRCC showed typical hypoenhancement and wash-out. 15 out of 60 (25%) pRCC showed atypical enhancement features; in 14 cases the contrast enhancement indicated a ccRCC. 1 complex cyst was falsely reported as IIF lesion. 59 out of 60 malignancies were reported as malignant using CEUS resulting in a sensitivity of 98.4%. CEUS is an eligible imaging technique to visualize the contrast enhancement features of pRCC. However, up to 25% of pRCCs show an atypical enhancement pattern making it difficult to distinguish it from other renal lesions.

Contemporary prevalence of carotid stenosis in patients presenting with ischaemic stroke.

Carotid stenosis is a common cause of ischaemic stroke and transient ischaemic attack (TIA). Despite rising recognition and centralization of stroke services there has been a decline in interventions for carotid stenosis in recent years. The aim of this study was to determine the current prevalence and management of carotid stenosis in the UK. This was a 1-year prospective observational study of consecutive patients presenting with ischaemic stroke, TIA or ischaemic retinal artery occlusion to a central London hyperacute stroke unit. Patients with significant carotid stenosis, defined as atherosclerotic narrowing of 50 per cent or greater, underwent multidisciplinary team (MDT) discussion to determine the cause of stroke/TIA and classify carotid stenosis as symptomatic or incidental. In total, 2707 patients were seen; half had an ischaemic event and the majority had carotid imaging (1252 of 1444). Carotid stenosis of at least 50 per cent was seen in 238 (prevalence 19·0 (95 per cent c.i. 16·6 to 21·4) per cent). Patients with significant carotid stenosis were more likely to have hypertension, hypercholesterolaemia, diabetes and ischaemic heart disease. Carotid stenosis was deemed symptomatic in 99 patients (7·9 (6·3 to 9·5) per cent); of these, 17 had carotid occlusion, 17 were unfit for surgery and 58 patients were referred for carotid intervention. Among 139 patients with asymptomatic stenosis, 75 had carotid stenosis ipsilateral to the stroke but, after MDT discussion, the cause was deemed to be atrial fibrillation (32), small-vessel disease (15), another determined cause (5), or not determined owing to atypical imaging or clinical presentation. Carotid stenosis is common, affecting one in five patients presenting with stroke or TIA. Careful MDT discussion may avoid unnecessary intervention and should be the standard of care.

Unusual Case of a Pancreatic Neuroendocrine Tumor Containing a Central Scar.

ABSTRACTWe report a previously unreported case of a pancreatic neuroendocrine tumor with a central scar mimicking a serous neoplasm. To our knowledge, this atypical imaging morphology of pancreatic neuroendocrine tumor has not been described before. Our report adds to the body literature that describes atypical imaging variants of neuroendocrine tumors and highlights that clinicians should be aware of the broad imaging characteristics of neuroendocrine tumors.

A case of magnetic foreign body ingestion in a child showing atypical X-ray imaging findings

A case of magnetic foreign body ingestion in a child showing atypical X-ray imaging findings

A large incidental adrenal mass in a patient with sudden-onset multiple organ failure

I describe a patient with sudden-onset multiple organ failure who was incidentally found to harbor a large adrenal mass. I hope this visual vignette will highlight that pheochromocytoma may exhibit atypical imaging features and can cause multiple organ failure in an otherwise apparently healthy patient.

Atypical Appearance of Hepatocellular Carcinoma and Its Mimickers: How to Solve Challenging Cases Using Gadoxetic Acid-Enhanced Liver Magnetic Resonance Imaging.

Hepatocellular carcinoma (HCC) can be diagnosed noninvasively with contrast-enhanced dynamic computed tomography, magnetic resonance imaging, or ultrasonography on the basis of its hallmark imaging features of arterial phase hyperenhancement and washout on portal or delayed phase images. However, approximately 40% of HCCs show atypical imaging features, posing a significant diagnostic challenge for radiologists. Another challenge for radiologists in clinical practice is the presentation of many HCC mimickers such as intrahepatic cholangiocarcinoma, combined HCC-cholangiocarcinoma, arterioportal shunt, and hemangioma in the cirrhotic liver. The differentiation of HCCs from these mimickers on preoperative imaging studies is of critical importance. Hence, we will review the typical and atypical imaging features of HCCs and the imaging features of its common mimickers. In addition, we will discuss how to solve these challenges in practice.

Should Spinal MRI Be Routinely Performed in Patients With Clinically Isolated Optic Neuritis?

Should Spinal MRI Be Routinely Performed in Patients With Clinically Isolated Optic Neuritis?

EP08.19: Typical and atypical dural sinus malformation imaging in the fetus: based on four cases

EP08.19: Typical and atypical dural sinus malformation imaging in the fetus: based on four cases

Diagnosis and Outcome of Biopsies of Indeterminate Lesions of the Cavernous Sinus and Meckel's Cave: A Retrospective Case Series in 85 Patients.

When clinical presentation, laboratory studies, or imaging cannot diagnose cavernous sinus (CS) and/or Meckel's cave (MC) lesions, biopsy may be necessary. To review our institutional series of biopsies of indeterminate CS and MC lesions. Records from January 1994 to June 2016 were searched for biopsied indeterminate CS and MC lesions. We defined indeterminate as having an atypical imaging appearance or a broad differential and the need for tissue for definitive diagnosis. We defined primary tumors as originating from cells inherent or near the CS and MC. Eighty-five patients were included (median age 59 [2-85] yr); 22 (28%) had a cancer history. Approaches included frontotemporal craniotomy (n = 48, 56%), endoscopic endonasal (n = 20, 24%), percutaneous transforamen ovale (n = 12, 14%), or retrosigmoid craniotomy (n = 5, 6%). Final diagnosis was metastatic in 27 (32%), primary in 21 (25%), inflammatory in 13 (15%), hematologic in 11 (13%), fungal in 5 (5%), and nondefinitive or nondiagnostic in 8 (10%) patients. Thirteen (59%) patients with a cancer history (n = 22) had a diagnosis consistent with their prior cancer; the remaining had a second pathology (n = 6, 27%) or nondiagnostic biopsy (n = 3, 14%). Two patients had surgical complications resulting in death. In this patient cohort, metastatic tumors were the most likely pathology. The biopsy threshold should be lower in patients with a cancer history if clinical or radiographic diagnosis is uncertain as 27% had a second disease. However, we consider biopsy as a last resort because the risk of major morbidity/mortality, while low, is not zero.

PET/CT in the Diagnosis and Workup of Sarcoidosis: Focus on Atypical Manifestations

Sarcoidosis is a multisystem disease characterized by the formation of noncaseating granulomas. Lung and intrathoracic lymph nodes are classic sites of involvement; however, sarcoidosis can affect any site in the body. The clinical course is extremely variable, and the imaging features are diverse and dependent on the affected site, degree of inflammation, and treatment the patient receives. Atypical manifestations and imaging findings can make diagnosis and/or management challenging. In addition, assessment of treatment response can be difficult in the setting of chronic disease. Fluorine 18 fluorodeoxyglucose (FDG) PET/CT is sensitive for assessment of the inflammatory activity of sarcoidosis in any organ. Although FDG PET/CT is not included in the standard workup for sarcoidosis, there has been growing evidence that supports the value of this examination in guiding diagnosis and management. FDG PET/CT may be especially useful for assessing reversible granuloma, treatment response, disease extent, occult disease, and cardiac or osseous sarcoidosis, and determining the most suitable biopsy site. Capability to image the entire body during a single examination is advantageous in cases of systemic disease such as sarcoidosis. The authors review the use of FDG PET/CT, providing up-to-date evidence and describing various cases of sarcoidosis in which FDG PET/CT has an important role in diagnosis and/or management. They also discuss the usefulness of FDG PET/CT in cases of selective manifestations of sarcoidosis. ©RSNA, 2018.

Biliary intraepithelial neoplasia in liver parenchyma of the caudate lobe: honeycomb appearance

Biliary intraepithelial neoplasia (BilIN) was newly defined by the WHO in 2010 and is characterized by biliary cell atypia with an intraductal papillary lesion. It is always found in the major bile duct, but not in liver parenchyma. A 50-mm irregular tumor was detected in the paracaval portion of the hepatic caudate lobe of a 61-year-old man. He had undergone total gastrectomy for advanced gastric cancer 2 years earlier. The tumor had increased from 20 to 50 mm in the last 6 months. Abdominal CT showed an irregular hypo-enhanced tumor, with a honeycomb appearance inside the tumor. Diffusion-weighted MRI and PET showed that the tumor had malignant features, though no tumor markers were elevated. The tumor seemed to invade into the inferior vena cava (IVC) and hepatic veins. At operation, under side clamping of the IVC, a total of 10 cm of ventral side IVC was resected with the left liver. Pathologically, the tumor was an inflammatory pseudo-tumor that contained intermediate-grade BilIN of persistent liver parenchyma in the tumor. The honeycomb appearance within the tumor showed a causal relationship between the pathological and etiological representations of BilIN. Considering BilIN avoids an unnecessary operation when we encounter atypical imaging findings of liver tumors.

MRI alterations in immunomodulation

In this review article, typical imaging findings of diseases elicited by immunomodulatory drugs are presented. Progressive multifocal leucoencephalopathy (PML), a subacute infection due to reactivation of the JC virus, has atypical magnetic resonance imaging (MRI) pattern, which must be considered in the framework of immunomodulatory multiple sclerosis (MS) treatment with natalizumab, fingolimod, rituximab and fumarate and also in lymphoproliferative diseases or other forms of immunosuppression. Restoration of the immune system may result in an overlapping and overwhelming immune response in terms of an immune reconstitution inflammatory syndrome (IRIS). Further conditions with typical MRI patterns comprise methotrexate-associated leucoencephalopathy and posterior reversible encephalopathy syndrome (PRES). In immunotherapy with activation of T‑lymphocytes, attention should always be paid to the fact that the T‑lymphocytes activated by different processes not only target the diseased tissue but also normal brain tissue.

Overcoming Atypical Imaging Features of Meningioma with High-Resolution Imaging and Advanced Imaging Techniques

Overcoming Atypical Imaging Features of Meningioma with High-Resolution Imaging and Advanced Imaging Techniques

Utility of volumetric contrast-enhanced and diffusion-weighted MRI in differentiating between common primary hypervascular liver tumors.

Differentiating between hepatocellular carcinoma (HCC), focal nodular hyperplasia (FNH), and hepatocellular adenoma (HCA) is usually achievable by MRI. However, in some cases with atypical imaging findings accurate diagnosis may be difficult. To assess the diagnostic value of volumetric contrast-enhanced (CE) and volumetric diffusion-weighted imaging (DWI) in differentiating between HCC, FNH, and HCA. Retrospective. In all, 143 patients (206 lesions): 42 HCA (81 lesions), 51 FNH (65 lesions), and 50 HCC (60 lesions). 1.5T MRI, T1 -T2 WI, DWI. Patients underwent CE-MRI and DWI (b = 0, 750 mm2 /s). Volumetric assessment of lesions' contrast enhancement and apparent diffusion coefficient (ADC) was performed with semiautomatic software after 3D image registration and segmentation by an observer and compared between three lesion groups. The diagnosis of lesions was based on histopathology, typical MRI findings, and/or follow-up. Independent t-test was used to compare parameters between two groups, one-way analysis of variance (ANOVA) between three groups, and receiver operator characteristic curve (ROC) analysis to define under-curve area and optimal cutoff. Mean values (±standard deviation) for HCC, FNH, and HCA, respectively, were: 1) arterial enhancement (%), 40.5 ± 13.2, 88.6 ± 32.6, 69.6 ± 25.1; 2) venous enhancement (%) 72.4 ± 22.1, 95.2 ± 30.9, 80.7 ± 30.6; and 3) ADC (10-6 mm2 /s) 1404.5 ± 168.1, 1413.4 ± 232.1, 1070.1 ± 232.1. ADC was the best differentiator of HCA from FNH (at 1211 × 10-6 mm2 /s; sensitivity 80.4%, specificity 71.7%) and arterial enhancement was the best differentiator of HCC from both HCA (at 48%; sensitivity 80.0%, specificity 80.5%) and FNH (at 52%; sensitivity 85.7%, specificity 85.4%). A combination of arterial enhancement and ADC (at 50% and 1227 × 10-6 mm2 /s) differentiated three types of tumors with high specificity (87.9%). Volumetric CE-MRI and volumetric DWI can help to differentiate between HCC, FNH, and HCA. 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;48:1080-1090.

Eosinophilic hepatitis mimicking hepatic metastases – a case report

Focal eosinophilic infiltration is a rare disease entity that in patients with malignancies may mimic malignant hepatic nodules Eosinophilic hepatitis is associated with a variety of disorders such as parasitic infestations allergic conditions internal malignancies drug hypersensitivity and hypereosinophilic syndrome In daily clinical practice eosinophilic abscess with typical or atypical imaging findings can mimic metastasis We hereby report a patient of eosinophilic hepatitis that mimicked hepatic metastases

Malignant solitary pulmonary nodules: assessment of mass growth rate and doubling time at follow-up CT.

The differentiation of benign and malignant solitary pulmonary nodules (SPNs), especially subsolid nodules, is still challenging because of the small size, slow growth, and atypical imaging characteristics of these nodules. We aimed to determine the significance of mass growth rate (MGR) and mass doubling time (MDT) at follow-up CT of malignant SPNs. This retrospective study included 167 patients (169 SPNs, diameter 8-30 mm). Among the 169 SPNs, 114 malignant SPNs were classified into three types: pure ground-glass nodules (pGGNs), part-solid nodules (pSNs), and solid nodules (SNs). These patients were followed up for at least 3 months. Three-dimensional manual segmentation was performed for all these nodules, and the intra- and inter-observer variabilities of diameter, volume, and mass measurement were assessed. From initial and follow-up CT scans, growth rates of the diameter, volume, and mass of the SPNs were compared. MDT and volume doubling time (VDT) were calculated and were compared among groups. Mass measurements had the best inter-observer consistency and intra-observer repeatability; the coefficients of variation of the mass measurements were the smallest. The mean growth rates of the diameter, volume, and mass of pGGNs, pSNs, and SNs significantly differed at different time points (P<0.001). Mean MDTs and VDTs of pGGNs, pSNs, and SNs were 655 vs. 848 days, 462 vs. 598 days, and 230 vs. 267 days, respectively (P<0.05). Mass measurements are an objective and accurate indicator in SPN assessment. During a 2-year follow-up, the mean growth rates of the diameter, volume, and mass of pGGNs, pSNs, and SNs differed at different time points, the greatest difference was observed in mean MGR. Mean MDT of malignant SPNs is less than the mean VDT.

The clinical features in Chinese patients with PRNP D178N mutation.

Fatal familial insomnia (FFI) is an autosomal dominant disease due to the D178N mutation of PRNP gene coupling with homozygous methionine (Met) at codon 129. It is generally considered that D178N mutation cases with 129M/M homozygotes present as FFI, and 129V/V as genetic CJD. However, the frequency of 129Met alleles in Chinese population is much higher than that in Caucasians. This study aims to investigate the clinical features and genetic characteristics of Chinese D178N mutants in this genetic context. We reviewed the clinical and genetic features of seven D178N patients. The clinical data, genetic data, electroencephalogram (EEG), brain magnetic resonance imaging (MRI), polysomnography (PSG), CSF 14-3-3 protein examinations of the seven patients were analyzed. The genotypes at codon 129 were all M/M. Four of the seven cases reported positive family history. Four patients were more likely the CJD phenotype and three were FFI phenotype according to the core clinical features. No major differences were found on the EEG, CSF 14-3-3 protein, and PSG presentations between this study and western studies. Novel neuroimaging findings were two patients had typical neuroimaging abnormalities of CJD and frontotemporal dementia, respectively. Unlike the western populations, the diverse phenotypical presentations of D178N mutants were not simply determined by the 129 genotypes in Chinese. The underlying modifying factors for phenotypical variations warrant further investigations. For those with atypical clinical and imaging features, genetic testing was important for final diagnosis.

An Unusual Presentation of Primary Hepatic Diffuse Large B-cell Lymphoma of the Liver

This report describes a case of primary hepatic diffuse large B-cell lymphoma (DLBCL) in a 64-year-old male who presented with constitutional symptoms, jaundice, abdominal swelling, and right upper quadrant pain. The diagnosis was confirmed on percutaneous liver biopsy. Notably, there was no evidence of extra-hepatic involvement. The patient received methylprednisolone and cyclophosphamide with good response but was lost to follow-up upon being transferred. This case highlights the importance of considering primary hepatic DLBCL in patients with unexplained abnormal liver tests and atypical imaging without solitary or discrete lesions, as this rare malignancy can present furtively.