Imaging Spectrum of Calvarial Abnormalities.

Calvarial abnormalities are usually discovered incidentally on radiologic studies or less commonly manifest with symptoms. This narrative review describes the imaging spectrum of the abnormal calvaria. The extent, multiplicity, and other imaging features of calvarial abnormalities can be combined with the clinical information to establish a final diagnosis or at least narrow the differential considerations. Prior trauma (congenital depression, leptomeningeal cysts, posttraumatic osteolysis), surgical intervention (flap osteonecrosis and burr holes), infection, and inflammatory processes (sarcoidosis) can result in focal bone loss, which may also be seen with idiopathic disorders without (bilateral parietal thinning and Gorham disease) or with (Parry-Romberg syndrome) atrophy of the overlying soft tissues. Anatomic variants (arachnoid granulations, venous lakes, parietal foramina) and certain congenital lesions (epidermoid and dermoid cysts, atretic encephalocele, sinus pericranii, and aplasia cutis congenita) manifest as solitary lytic lesions. Other congenital entities (lacunar skull and dysplasia) display a diffuse pattern of skull involvement. Several benign and malignant primary bone tumors involve the calvaria and manifest as lytic, sclerotic, mixed lytic and sclerotic, or thinning lesions, whereas multifocal disease is mainly due to hematologic or secondary malignancies. Metabolic disorders such as rickets, hyperparathyroidism, renal osteodystrophy, acromegaly, and Paget disease involve the calvaria in a more diffuse pattern. Online supplemental material is available for this article. ©RSNA, 2021.

Carotid web prevalence in a large hospital-based cohort and its association with ischemic stroke.

Carotid artery webs are shelf-like protrusions of intimal fibrous tissue arising from the posterior wall of the carotid bulb, found to have a 2.3% prevalence in the United States. Previous studies have demonstrated its association with ipsilateral anterior circulation stroke. The aim of this study is to assess the prevalence of carotid webs in the largest US epidemiologic study to date, and to further characterize the clinical features of carotid web patients. We assembled a cohort of 1467 adult patients with CT angiogram neck from January 1, 2011 to January 1, 2017. CT angiograms were reviewed for diagnosis of carotid web. Demographic and clinical details of web patients were obtained. Differences in demographics and CT angiogram indication between patients with and without carotid web were assessed using appropriate statistical tests. Twenty-four (24/1467 = 1.6%) carotid web patients were identified (mean age: 63 years; 62.5% female; 50% African American). Twelve (12/24 = 50%) had ipsilateral anterior circulation stroke. Of them, 8 were deemed cryptogenic. Four (4/24 = 16.7%) web patients had at least one recurrent stroke in the ipsilateral anterior circulation. One case was reported on the radiology report at the time the study was initially performed. This study confirms a prevalence of 1.6% in our urban, North American cohort. Among carotid web patients, there was a high incidence of ipsilateral anterior circulation stroke, the majority of which were classified as cryptogenic. This study affirms the importance of the diagnosis of carotid web, especially in cryptogenic stroke patients, as a potential unrecognized stroke risk factor.

Venous Sinus Thrombosis in Blunt Trauma: Incidence and Risk Factors.

PURPOSE: The aim of our study was to determine the incidence and risk factors of dural venous sinus thrombosis and epidural hemorrhage in the setting of a blunt trauma causing a calvarial fracture crossing a dural venous sinus. METHODS: A retrospective review of 472 blunt trauma patients with calvarial fracture crossing a dural venous sinus was performed. Two hundred ten patients who underwent computed tomography venography were identified and evaluated for the presence of dural venous sinus thrombosis and/or epidural hemorrhage. Site and displacement of fractures, as well as age, sex, Glasgow Coma Scale (GCS) score, and mechanism of injury, were considered for potential predictive value of thrombosis and/or epidural hemorrhage. RESULTS: We found a 23% incidence of dural venous sinus thrombosis in patients with a fracture traversing a dural venous sinus. Significant predictors of thrombosis included temporal fracture (38% incidence) and skull base fracture (31% incidence). Occipital fracture not involving the skull base was associated with a significantly decreased risk of thrombosis, with an incidence of 9%. Decreased GCS score and fall from height greater than 10 feet additionally predicted dural venous sinus thrombosis. Significant predictors of epidural hemorrhage included parietal fractures and displaced fractures, although a large percentage of nondisplaced fractures in other bones demonstrated epidural hemorrhage as well. CONCLUSIONS: Dural venous sinus thrombosis in the setting of blunt trauma with a calvarial fracture crossing a dural venous sinus has an incidence of 23%. Increased suspicion for thrombosis is warranted in patients with temporal or skull base fractures, low GCS score, and recent fall from great height.

Review of COVID-19, part 2: Musculoskeletal and neuroimaging manifestations including vascular involvement of the aorta and extremities.

The coronavirus disease 2019 (COVID-19) pandemic caused by the novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) has affected almost every country in the world resulting in severe morbidity, mortality and economic hardship, altering the landscape of healthcare forever. Its devastating and most frequent thoracic and cardiac manifestations have been well reported since the start of the pandemic. Its extra-thoracic manifestations are myriad and understanding them is critical in diagnosis and disease management. The role of radiology is growing in the second wave and second year of the pandemic as the multiorgan manifestations of COVID-19 continue to unfold. Musculoskeletal, neurologic and vascular disease processes account for a significant number of COVID-19 complications and understanding their frequency, clinical sequelae and imaging manifestations is vital in guiding management and improving overall survival. The authors aim to provide a comprehensive overview of the pathophysiology of the virus along with a detailed and systematic imaging review of the extra-thoracic manifestation of COVID-19. In Part I, abdominal manifestations of COVID-19 in adults and multisystem inflammatory syndrome in children will be reviewed. In Part II, manifestations of COVID-19 in the musculoskeletal, central nervous and vascular systems will be reviewed.

Review of COVID-19, part 1: Abdominal manifestations in adults and multisystem inflammatory syndrome in children.

The coronavirus disease 2019 (COVID -19) pandemic caused by the novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) has affected almost every country in the world, resulting in severe morbidity, mortality and economic hardship, and altering the landscape of healthcare forever. Although primarily a pulmonary illness, it can affect multiple organ systems throughout the body, sometimes with devastating complications and long-term sequelae. As we move into the second year of this pandemic, a better understanding of the pathophysiology of the virus and the varied imaging findings of COVID-19 in the involved organs is crucial to better manage this complex multi-organ disease and to help improve overall survival. This manuscript provides a comprehensive overview of the pathophysiology of the virus along with a detailed and systematic imaging review of the extra-thoracic manifestation of COVID-19 with the exception of unique cardiothoracic features associated with multisystem inflammatory syndrome in children (MIS-C). In Part I, extra-thoracic manifestations of COVID-19 in the abdomen in adults and features of MIS-C will be reviewed. In Part II, manifestations of COVID-19 in the musculoskeletal, central nervous and vascular systems will be reviewed.

Bovine Arch and Stroke Laterality.

Background Left-hemispheric strokes are more frequent and often have a worse outcome than their right-hemispheric counterparts. This study aimed to evaluate whether cardioembolic stroke laterality is affected by anatomical characteristics of the aortic arch. We hypothesized that laterality varies between patients with bovine versus standard arch. Methods and Results We retrospectively identified 1598 acute cardioembolic strokes in patients with atrial fibrillation from our institutional stroke database (2009-2017). Inclusion criteria were acute anterior circulation ischemic infarct and availability of both arch and brain imaging (magnetic resonance imaging or computed tomography). Alternative causes of stroke and anomalous arch were excluded. Imaging was reviewed for stroke characterization and laterality and arch branching pattern. Bovine arch denotes a common origin of the brachiocephalic trunk and left common carotid artery. Strokes were classified as bilateral (left or right). Univariate analysis was performed using chi-square tests. The final cohort comprised 615 patients, mean age 77 years (SD 11.8 years) with 376 women (61%) and 33% white, 30% black, and the remainder mixed/Hispanic. Standard arch (n=424) stroke distribution was left 43.6% (185), right 45.1% (191), and bilateral 11.3% (48). Bovine arch (n=191) stroke distribution was left 51.3% (98), right 35.6% (68), and bilateral 13.1% (25). Bovine arches were associated with more left-sided strokes compared with standard arches (P=0.018). There was an association between black race and bovine arch (P=0.0001). Conclusions Bovine aortic arch configuration is associated with left hemispheric laterality of cardioembolic stroke. This study enriches the understanding that arch anatomy influences stroke laterality and highlights the need for further research into the causative hemodynamic factors.

Occipital tip injury with homonymous central scotoma: OCT-NFL and RGC correlation.

PURPOSE: To report one case of homonymous paracentral scotoma with corresponding optical coherence tomography (OCT) findings in a young woman after injury to the left occipital lobe tip. OBSERVATIONS: A young woman with past medical history of Hodgkin's lymphoma and large B-cell lymphoma metastatic to the left occipital lobe status post resection presented to the eye clinic with a chief complaint of a "blind spot" in the right eye since her surgery. Humphrey visual field (HVF) showed a right homonymous paracentral scotoma corresponding to the non-decussating and decussating optic radiation for central vision originating from the left lateral geniculate nucleus (LGN). OCT confirmed atrophy of the right nasal hemifovea with fibers originating from the papillomacular bundle and the left temporal hemifovea with fibers originating from the superior temporal segment of the optic nerve. These fibers correspond to the central vision involved with the left posterior occipital lobe tip. CONCLUSIONS AND IMPORTANCE: We report a case of right homonymous central vision loss as a result of injury to the left posterior occipital lobe tip with certain unique features. Here, a small lesion in the posterior visual pathway led to a relatively large loss of ganglion cell layer.

Posterior Reversible Encephalopathy Syndrome and Reversible Cerebral Vasoconstriction Syndrome: Distinct Clinical Entities with Overlapping Pathophysiology.

The clinical and radiologic manifestations of posterior reversible encephalopathy syndrome and reversible cerebral vasoconstriction syndrome are reviewed. The relationship between these entities is discussed. A hypothesis of a common underlying pathophysiology is proposed and substantiated based on the current medical literature.

Sturge-Weber syndrome: deep venous occlusion and the radiologic spectrum.

Sturge-Weber syndrome is a neurocutaneous syndrome with a facial port-wine nevus and neurologic features, typically including seizures and hemiparesis. Glaucoma may also occur. MRI features include leptomeningeal angiomatosis, cortical and pial calcifications, and angiomatous change of the choroid plexus. We reviewed a subset of patients with Sturge-Weber syndrome with the rare finding of deep venous occlusion, and present such a case, unusual by comparison to previously reported cases of Sturge-Weber syndrome with deep venous occlusion. Six previously reported cases were reviewed. All cases presented with seizures; five of six had evidence of leptomeningeal angiomatosis; half had cerebral hemiatrophy. This report presents a unique case lacking clinical seizures, but with a port-wine stain and congenital glaucoma. This patient lacked the radiologic findings of leptomeningeal angiomatosis and hemicerebral atrophy, but demonstrated deep venous occlusion with frontal venous collaterals. There is a wide spectrum of findings in Sturge-Weber syndrome. The lack of seizures and angiomatosis in this case are likely "true-true" and related. The case illustrates the unusual finding of deep venous occlusion in Sturge-Weber syndrome occurring without leptomeningeal angiomatosis. Additionally, it demonstrates that although the initial evaluation is normal, patients may later manifest clinical characteristics of Sturge-Weber syndrome.

Paradoxical migrating cyst: an unusual presentation of intraventricular neurocysticercosis with a coincidental pituitary adenoma.

Intraventricular neurocysticercosis is an uncommon entity which may become symptomatic due to cerebrospinal fluid flow obstruction. Migration of intraventricular cysts through the ventricular spaces is a rare occurrence. This phenomenon is poorly understood but may be due to pressure changes within the ventricular cavities. We present a patient with intraventricular neurocysticercosis with paradoxical transaqueductal migration of the cyst from the cerebral aqueduct to the fourth ventricle shortly after ventricular drain placement for acute hydrocephalus. The patient also presented with a coincidental sellar and suprasellar mass, later pathologically proven to be a pituitary adenoma. The migration of this cyst resulted in spontaneous relief of obstruction at the cerebral aqueduct, thus restoring normal cerebrospinal fluid pathways and avoiding permanent shunting. We discuss the possible mechanisms and implications of cyst migration, and the diagnostic challenges of concomitant findings of a pituitary mass and neurocysticercosis. Although the presence of a sellar and suprasellar mass in a patient with known neurocysticercosis should raise clinical suspicion for the possibility of sellar neurocysticercosis, pituitary macroadenoma is a more common entity and a more likely etiology for a sellar lesion.