Neurofibromatosis from Head to Toe: What the Radiologist Needs to Know.

Neurofibromatosis type 1 (NF1) and neurofibromatosis type 2 (NF2) are autosomal dominant inherited neurocutaneous disorders or phakomatoses secondary to mutations in the NF1 and NF2 tumor suppressor genes, respectively. Although they share a common name, NF1 and NF2 are distinct disorders with a wide range of multisystem manifestations that include benign and malignant tumors. Imaging plays an essential role in diagnosis, surveillance, and management of individuals with NF1 and NF2. Therefore, it is crucial for radiologists to be familiar with the imaging features of NF1 and NF2 to allow prompt diagnosis and appropriate management. Key manifestations of NF1 include café-au-lait macules, axillary or inguinal freckling, neurofibromas or plexiform neurofibromas, optic pathway gliomas, Lisch nodules, and osseous lesions such as sphenoid dysplasia, all of which are considered diagnostic features of NF1. Other manifestations include focal areas of signal intensity in the brain, low-grade gliomas, interstitial lung disease, various abdominopelvic neoplasms, scoliosis, and vascular dysplasia. The various NF1-associated abdominopelvic neoplasms can be categorized by their cellular origin: neurogenic neoplasms, interstitial cells of Cajal neoplasms, neuroendocrine neoplasms, and embryonal neoplasms. Malignant peripheral nerve sheath tumors and intracranial tumors are the leading contributors to mortality in NF1. Classic manifestations of NF2 include schwannomas, meningiomas, and ependymomas. However, NF2 may have shared cutaneous manifestations with NF1. Lifelong multidisciplinary management is critical for patients with either disease. The authors highlight the genetics and molecular pathogenesis, clinical and pathologic features, imaging manifestations, and multidisciplinary management and surveillance of NF1 and NF2. Online supplemental material is available for this article. ©RSNA, 2022.

Radiologic and Pathologic Correlation in EVALI.

OBJECTIVE. The purpose of this article is to characterize the appearance on CT of e-cigarette or vaping product use-associated lung injury (EVALI) in a cohort with histopathologic evidence of this disorder. MATERIALS AND METHODS. Twenty-four patients with EVALI were identified. Chest CT examinations were reviewed by two radiologists for various chest CT findings. For comparison with pathologic findings, CT assessments were distilled into previously described patterns of EVALI seen on CT: acute lung injury (ALI), chronic eosinophilic pneumonia (CEP) or organizing pneumonia (OP), acute eosinophilic pneumonia (AEP), alveolar hemorrhage, hypersensitivity pneumonitis (HP), lipoid pneumonia, and mixed or unclassifiable patterns. RESULTS. Sixteen of 24 (67%) patients were men; the mean age was 34.5 years (range, 17-67 years). The most common CT finding was ground-glass opacities, which was present in 23 of 24 (96%) patients and the dominant finding in 18 of 24 (75%) patients. Consolidation was the next most common finding in 42% of patients. Interlobular septal thickening was present in 29%. Lobular low attenuation was conspicuous in six patients. Distribution was multifocal in 54% of patients, peripheral in 17%, and centrally predominant in 8%. Subpleural sparing was seen in 45%. The predominant CT pattern was ALI (42%), concordant with histopathologic findings in 75%; the next most predominant pattern was ground-glass opacity centrilobular nodules resembling HP (33%). A CT pattern of CEP or OP was seen in 13% of patients, all showing ALI on lung biopsy. No patient showed macroscopic lung parenchymal fat. Two patients with CT ALI patterns showed OP on histopathologic examination. Of the eight patients with ground-glass opacity centrilobular nodules resembling HP at CT, none showed HP at histopathologic examination. CONCLUSION. EVALI manifests at CT as ALI with multifocal ground-glass opacity, often with organizing consolidation, and a small centrilobular nodular pattern resembling HP.

Left Ventricular Septal Hypertrophy in Elderly Patients With Aortic Stenosis.

OBJECTIVES: Left ventricular (LV) septal hypertrophy in aortic stenosis raises diagnostic and therapeutic questions. However, the etiology and clinical consequences of this finding have not been well studied. The aim of this study was to perform a morphologic evaluation of the LV in aortic stenosis and to investigate the contributing factors and consequences of septal hypertrophy. METHODS: Patients with moderate or severe aortic stenosis were prospectively enrolled. Patients with previous myocardial infarction, wall motion abnormalities, at least moderate valvular regurgitation, known cardiomyopathy, an LV ejection fraction of less than 50%, and age younger than 65 years were excluded. RESULTS: Forty-one patients underwent a final analysis. Septal hypertrophy (LV septal wall thickness ≥15 mm) was confirmed in 21 of 41 patients. The septal hypertrophy group had higher peak aortic valve velocity, a higher diabetes mellitus rate, and a higher rate and longer duration of hypertension than those without septal hypertrophy. The peak aortic valve velocity (odds ratio, 7.1; 95% confidence interval, 1.4-37.1) and diabetes mellitus (odds ratio, 7.4; 95% confidence interval, 1.2-46.2) were the significant factors associated with septal hypertrophy by multivariate analysis. Intraventricular conduction disturbance on electrocardiography was more frequent in the septal hypertrophy group (P = .021). CONCLUSIONS: Left ventricular septal hypertrophy was commonly observed in elderly patients with aortic stenosis, and a higher aortic valve velocity, hypertension, and diabetes mellitus were associated factors. Intraventricular conduction disturbance occurred more often in patients with septal hypertrophy than those without, which implies the pathophysiologic consequence. Further studies are needed to determine the impact of septal hypertrophy and intraventricular conduction disturbance on the prognosis of patients after aortic valve interventions.

Dendriform Pulmonary Ossification in the Absence of Usual Interstitial Pneumonia: CT Features and Possible Association With Recurrent Acid Aspiration.

OBJECTIVE: Dendriform pulmonary ossification (DPO) is a rare lung disease in which mature bone is present in the peripheral interstitium of the lung. It typically occurs in patients with usual interstitial pneumonia (UIP). We assessed patients with CT findings of DPO without UIP to determine possible causative factors and to assess the clinical and CT course. We hypothesized that DPO without UIP would be a unique entity. MATERIALS AND METHODS: We retrospectively reviewed CT reports for the word "ossification." Two observers reviewed each examination for micronodules 1-5 mm in diameter in the peripheral interstitium (subpleural and perifissural spaces and interlobular septa), some of which had high attenuation on mediastinal windows, presence of contiguous clusters of nodules resulting in a branching pattern, and lack of findings of UIP or focal lung disease. We reviewed the electronic medical records and follow-up CT and clinical information in all eligible patients. RESULTS: The study population consisted of 52 men with a median age of 79 years old. Seventy-five percent of the patients had gastroesophageal reflux disease, obstructive sleep apnea, or a chronic neurologic disorder. No progressive pulmonary symptoms were attributed directly to DPO, and no patient developed pulmonary fibrosis or suffered clinical decline from DPO. CT showed minimal progression or remained stable at follow-up (77% for at least 1 year, 25% for over 4 years). CONCLUSION: DPO in the absence of UIP occurs in elderly men and appears to be associated with chronic aspiration of gastric acid. The course is indolent.

Diagnosis of Usual Interstitial Pneumonitis in the Absence of Honeycombing: Evaluation of Specific CT Criteria With Clinical Follow-Up in 38 Patients.

OBJECTIVE: We sought to evaluate specific CT criteria for the diagnosis of usual interstitial pneumonitis (UIP) in the absence of honeycombing. These criteria included peripheral reticulation and lobular distortion; some upper lobe involvement, but a lower zone predominance; a heterogeneous appearance with areas of normal lung, minimal reticulation, and substantial distortion alternating throughout the study and often on an individual image; a nonsegmental distribution; and traction bronchiectasis. MATERIALS AND METHODS: We searched reports of CT studies performed between January 1, 2009, and January 1, 2012, to identify patients for whom UIP was a likely or probable diagnosis and reviewed the CT study for each case (n = 106). There were 38 patients who met all CT criteria and who also had a clinical diagnosis of idiopathic UIP (also known as idiopathic pulmonary fibrosis [IPF]) and follow-up of at least 6 months, as determined from the electronic medical record. We reviewed prior and subsequent CT examinations in this cohort. RESULTS: The median age of our patients was 80 years, and the duration of clinical follow-up was 6-104 months (mean, 38 months; median, 37 months). For all patients, a pulmonary medicine physician made a working diagnosis of IPF. Fifteen patients died from pulmonary complications, and 16 of the surviving patients had clinical or functional progression of disease. There were no instances in which the initial diagnosis was revised or reversed. CONCLUSION: Strict application of specific CT criteria may allow a specific diagnosis of UIP in the proper clinical setting in the absence of honeycombing.

The Incremental Value of Magnetic Resonance Imaging for Identification of Apical Pouch in Patients with Apical Variant of Hypertrophic Cardiomyopathy.

BACKGROUND: The development of a left ventricular (LV) apical pouch in patients with apical hypertrophic cardiomyopathy (aHCM) has been thought to be the transition point that can become an apical aneurysm, which is linked to higher risk of adverse events. In our study, we sought to compare the ability of transthoracic echocardiography (echo) and cardiac magnetic resonance imaging (cMRI) to accurately identify the presence of an apical pouch or aneurysm in patients with aHCM. METHODS: We retrospectively reviewed the charts of all consecutive patients that had features of aHCM on imaging. Data from cMRI and echo examinations were abstracted, and the ability of these diagnostic modalities to identify the presence of a LV apical pouch and aneurysm was analyzed. RESULTS: Of 31 patients with aHCM, 17 (54.8%) had an apical pouch and 2 were found to have apical aneurysm (6.5%) on cMRI. Echo with and without perflutren contrast was able to accurately identify both aneurysms, but only 47.1% (8/17) of apical pouches seen by cMRI. Two patients had apical thrombus that was identified by cMRI, but not by echo. CONCLUSION: Our findings indicate that cMRI is superior to echo in identifying apical pouches in patients with aHCM. Our results also suggest that in patients undergoing echo, the use of perflutren contrast for LV opacification increases the diagnostic yield. Further study is necessary to delineate whether earlier identification of an apical pouch will be of clinical benefit for patients with aHCM by altering clinical management and avoiding adverse cardiovascular events.

Hypoplasia, pseudocoarctation and coarctation of the aorta - a systematic review.

Aortic arch abnormalities are uncommon and may be seen in association with other congenital cardiac anomalies. Coarctation, pseudocoarctation and hypoplastic aortic arch are known aortic arch abnormalities, with the former being well studied, whilst for the latter two, much less is known. There are similarities and differences that are important to distinguish among these three conditions in order to avoid errors in diagnosis that may result in unnecessary investigations, which may in turn result in physical or emotional harm to the patient. For this reason, we present a systematic review of the published literature providing an evidence-based overview that may be helpful to clinicians when faced with this diagnostic dilemma.

Anomalous origin of the circumflex artery from the right pulmonary artery.

Anomalous origin of the circumflex artery from the pulmonary artery (ACxAPA) is a rare but clinically significant condition in which the circumflex artery arises from either the main pulmonary artery or one of its main branches. Untreated patients with ACxAPA may develop severe heart failure or sudden cardiac death. Diagnosis is established with either catheter or CT angiography. We present a case of an adult male with no prior known cardiac history who was found to have ACxAPA after presenting to our institution in acute decompensated heart failure.

UIP diagnosed at surgical lung biopsy, 2000-2009: HRCT patterns and proposed classification system.

OBJECTIVE: High resolution CT (HRCT) is diagnostic of usual interstitial pneumonia (UIP) if honeycombing is present. However, biopsy-proven UIP also occurs in patients without honeycombing. Identification of specific HRCT patterns may enable specific diagnosis and allow more patients to enter clinical trials. Pattern may also predict prognosis. We sought to identify specific HRCT patterns in patients with biopsy-proven UIP (2000-2009) and to assess outcomes and serial change in pattern. MATERIALS AND METHODS: We reviewed the HRCT findings in 44 patients with biopsy-proven UIP and identified four distinct patterns: classic UIP (cUIP) with honeycombing, fibrosis without honeycombing (FnoH), minimal fibrosis (Fmin), and ground-glass present (GGOp). We reviewed electronic medical records for outcome information and serial HRCT examinations when available. RESULTS: The extent of fibrosis varied between patterns; findings were always heterogeneous in the cUIP and FnoH patterns. Some Fmin patients had a more homogeneous appearance. The lower lobes were predominantly affected, but upper lobe abnormalities were always present. Mortality from respiratory failure and acute exacerbations occurred regardless of pattern. Serial progression from Fmin to FnoH to cUIP occurred, although in a variable manner. Some individuals had an acute illness (GGOp) as the initial manifestation of UIP. CONCLUSION: The FnoH pattern may be diagnostic of UIP in the proper clinical setting; heterogeneity of HRCT appearance is critical and has not been previously emphasized. Grouping of patients on the basis of pattern may allow more accurate assessment of treatment effects. Further validation and study of these HRCT patterns is warranted. Histologic UIP predicts clinical course.

Does the presence of mediastinal adenopathy confer a risk for disseminated infection in immunocompetent persons with pulmonary coccidioidomycosis?

Pulmonary coccidioidomycosis is caused by inhaling airborne arthroconidia of Coccidioides, a soil-dwelling fungus endemic to the desert southwestern United States. Although uncommon, disseminated coccidioidal infection can be associated with well-defined risk factors, such as cell-mediated immunodeficiency, certain racial heritages (e.g. African or Filipino), male sex, or pregnancy. Before widespread use of computed tomography (CT), the presence or persistence of mediastinal lymphadenopathy was postulated to be a risk factor for disseminated coccidioidal infection. To investigate the use of CT scanning to identify the presence of mediastinal lymphadenopathy in patients with pulmonary coccidioidomycosis, and to correlate such lymphadenopathy with disseminated coccidioidal infection, we performed a retrospective review of patients with pulmonary coccidioidomycosis who were evaluated by chest CT. Two radiologists independently interpreted 150 CT scans from patients with pulmonary coccidioidomycosis. Forty-nine patients met CT criteria for mediastinal lymphadenopathy, whereas 101 patients did not. Disseminated coccidioidal infection was observed in 5 (10%) of the 49 patients with mediastinal lymphadenopathy and in 6 of the 101 (6%; P = .34) without such adenopathy. Among patients with coccidioidomycosis, patients with mediastinal lymphadenopathy, as assessed by CT, had a higher rate of disseminated infection, but the difference was not statistically significant.

Coronary calcium quantification using contrast-enhanced dual-energy computed tomography scans.

The purpose of this study is to evaluate a direct measure of calcium burden by using dual-energy computed tomography (DECT) during contrast-enhanced coronary imaging, potentially eliminating the need for an extra noncontrast X-ray acquisition. The ambiguity of separation of calcium from contrast material on contrast-enhanced images was solved by using virtual noncontrast images obtained by DECT. A new threshold CT number was required to detect the calcium carrying potential risk for adverse coronary events on virtual noncontrast images. Two methods were investigated to determine the 130 HU threshold for DECT scoring. An in vitro anthropomorphic phantom with 29 excised patient calcium plaques inserted was used for both a linear and a logistic regression analysis. An IRB approved in vivo prospective study of six patients was also performed to be used for logistic regression analysis. The threshold found by logistic regression model to define the calcium burden on virtual noncontrast images detects the calcium carrying potential risk for adverse coronary events correctly (2.45% error rate). DECT calcium mass and volume scores obtained by using the threshold correlates with both conventional Agatston and volume scores (r = 0.98, p < 0.001). A conventional CT cardiac exam requires two scans, including a noncontrast scan for calcium quantification and a contrast-enhanced scan for coronary angiography. With the ability to quantify calcium on DECT contrast-enhanced images, a DECT cardiac exam could be accomplished with one contrast-enhanced scan for both calcium quantification and coronary angiography. 

Coronary artery ectasia in an adult Noonan syndrome detected on coronary CT angiography.

Coronary ectasia is rare in patients with Noonan syndrome. When suspected during echocardiography more common causes including Kawasaki disease in children and atherosclerosis coronary artery disease in adults should be ruled out. Coronary CT angiogram, a non-invasive imaging tool may be preferred over conventional coronary angiogram in the initial diagnosis and monitoring the progression of coronary ectasia in such patients. Aspirin may be considered to prevent coronary thrombosis.

Symptomatic pericardial cyst: a case series.

Pericardial cysts are most commonly located at the cardiophrenic angle or, rarely, in the posterior or anterior superior mediastinum. The majority of pericardial cysts are asymptomatic and are found incidentally. Symptomatic pericardial cysts present with dyspnoea, chest pain, or persistent cough. We describe four patients with symptomatic pericardial cysts who were treated with either echocardiographically guided percutaneous aspiration or video-assisted thoracoscopic surgery, or both; thoracotomy; or conservative therapy.

Takotsubo cardiomyopathy in a patient with pulmonary embolism.

Takotsubo cardiomyopathy is an acute cardiac syndrome characterized by transient regional wall motion abnormalities of the left ventricular apex or midventricle. Patients often present with chest pain or dyspnoea, ST-segment elevation, and minor elevations of cardiac enzyme levels. Takotsubo cardiomyopathy has been associated with severe emotional or physical stress such as severe burns, spinal cord injury, subarachnoid haemorrhage, and multiple traumas. We report a case of takotsubo cardiomyopathy in a 79-year-old woman with pulmonary embolism. Although pulmonary embolism has been listed as a potential cause of takotsubo cardiomyopathy, this is the first case reported with this association.

Pulmonary Injury Resulting from Vaping or e-Cigarette Use: Imaging Appearances at Presentation and Follow-up.

Electronic cigarette or vaping product use-associated lung injury most frequently presents with an acute lung injury pattern at CT, manifesting as multifocal ground-glass opacity and/or consolidation, typically multifocal and multilobar, possibly with subpleural sparing. Areas of organization, manifesting as contracting consolidation, mild architectural distortion, intralobular lines, lobular distortion, and traction bronchiectasis may occur as the illness evolves. A CT appearance resembling hypersensitivity pneumonitis, reflecting the exquisitely bronchiolocentric micronodular lesions of organizing pneumonia and acute lung injury seen at histopathologic findings in these patients, may be encountered. Less common CT appearances include organizing pneumonia or acute eosinophilic pneumonia patterns, the latter consisting of multifocal opacity and smooth interlobular septal thickening, possibly with small effusions, but without clinical evidence of volume overload. Patients may present with pneumothorax or pneumomediastinum, or these conditions may develop during their illness course. Most patients improve clinically and at imaging on follow-up, particularly following exposure cessation and corticosteroid therapy, but the time course to improvement is variable and most likely related to the severity of the lung injury. Radiologists should be familiar with the imaging manifestations of vaping-associated pulmonary injury, and the possibility of this condition should be considered when the imaging findings reviewed in this article are encountered. © RSNA, 2020.

Pneumocytic adenomyoepithelioma: A case providing support for the benignity of this extremely rare pulmonary neoplasm.

Pneumocytic adenomyoepithelioma is an extremely rare and poorly understood pulmonary neoplasm, so experience with this tumor is limited. Since the initial case series where the lesion was first proposed as a distinctive entity, only one additional report has been described. We present a case of pneumocytic adenomyoepithelioma with clinical and radiologic data that provide the first long-term evidence of the benignity of this extremely rare pulmonary neoplasm. We also review the available literature surrounding pneumocytic adenomyoepitheliomas. Our case provides important new data on the behavior of this lesion, as imaging studies showed essentially stable or very slowly progressive disease over the course of approximately 9 years. Collectively, this rare and poorly described lesion appears to behave in an indolent or benign fashion, a notion that our case further supports.