Retinoblastoma: What the Neuroradiologist Needs to Know.

Retinoblastoma is the most common primary intraocular tumor of childhood. Accurate diagnosis at an early stage is important to maximize patient survival, globe salvage, and visual acuity. Management of retinoblastoma is individualized based on the presenting clinical and imaging features of the tumor, and a multidisciplinary team is required to optimize patient outcomes. The neuroradiologist is a key member of the retinoblastoma care team and should be familiar with characteristic diagnostic and prognostic imaging features of this disease. Furthermore, with the adoption of intra-arterial chemotherapy as a standard of care option for globe salvage therapy in many centers, the interventional neuroradiologist may play an active role in retinoblastoma treatment. In this review, we discuss the clinical presentation of retinoblastoma, ophthalmic imaging modalities, neuroradiology imaging features, and current treatment options.

Cervicofacial Venous Malformations Are Associated with Intracranial Developmental Venous Anomalies and Dural Venous Sinus Abnormalities.

BACKGROUND AND PURPOSE: Prior studies have suggested an association between the presence of cervicofacial venous malformations and intracranial developmental venous anomalies. We reviewed our institutional cohort of patients with cervicofacial venous malformations and examined the spectrum of intracranial venous anomalies, including developmental venous anomalies, cavernous malformations, and dural venous sinus abnormalities. MATERIALS AND METHODS: Consecutive patients who presented to our institution with cervicofacial venous malformations and underwent postcontrast MR imaging were studied. Three neuroradiologists reviewed brain MRIs for the presence of developmental venous anomalies, dural venous sinus ectasia, and cavernous malformations. The prevalence of developmental venous anomalies in this patient population was compared with an age- and sex-matched control group without venous malformations at a ratio of 1:2. Categoric variables were compared with χ2 tests. RESULTS: Sixty-three patients with venous malformations met the inclusion criteria with a mean age of 38.3 ± 24.0 years. The overall presence of developmental venous anomalies in patients with venous malformations was 36.5% (23/63) compared with 7.9% (10/126) in controls (P < .001). The prevalence of dural venous sinus ectasia was 9.5% (6/63) compared with 0% for controls (P = .002). One patient with a venous malformation had a cavernous malformation compared with 1 patient in the control group (P = .62). In 73.9% of patients (17/23), developmental venous anomalies were along the same metamere; and in 82.6% of patients, developmental venous anomalies were ipsilateral to the venous malformations. CONCLUSIONS: Our case-control study demonstrated a significant association between cervicofacial venous malformations and cerebral developmental venous anomalies as well as between cervicofacial venous malformations and dural venous sinus abnormalities. Our findings suggest that venous malformations may be the result of a segmental in utero insult to cells involved in cerebrofacial venous development.

The Forgotten Second Window: A Pictorial Review of Round Window Pathologies.

The round window serves to decompress acoustic energy that enters the cochlea via stapes movement against the oval window. Any inward motion of the oval window via stapes vibration leads to outward motion of the round window. Occlusion of the round window is a cause of conductive hearing loss because it increases the resistance to sound energy and consequently dampens energy propagation. Because the round window niche is not adequately evaluated by otoscopy and may be incompletely exposed during an operation, otologic surgeons may not always correctly identify associated pathology. Thus, radiologists play an essential role in the identification and classification of diseases affecting the round window. The purpose of this review is to highlight the developmental, acquired, neoplastic, and iatrogenic range of pathologies that can be encountered in round window dysfunction.

Imaging Features of Juvenile Xanthogranuloma of the Pediatric Head and Neck.

BACKGROUND AND PURPOSE: Juvenile xanthogranuloma is a non-Langerhans cell histiocytosis primarily affecting children. The purpose of this study was to characterize the imaging features of histologically confirmed pediatric head and neck juvenile xanthogranuloma. MATERIALS AND METHODS: A retrospective review was performed of medical records and imaging of histologically confirmed head and neck juvenile xanthogranuloma. RESULTS: Ten patients (6 girls, 4 boys) 1 month to 12 years of age were imaged with ultrasound only (n = 1), CT only (n = 2), CT and ultrasound (n = 1), MR imaging only (n = 3), or MR imaging and CT (n = 3). Masses were solitary in 9 patients and multiple in 1. Solitary masses were located in the external auditory canal, infra-auricular region, infratemporal fossa with intracranial extension, frontal scalp, and subperiosteal space eroding the calvaria and along the dura. One patient with disseminated disease had scalp-, calvarial-, and dural-based masses. Clinical presentation included a mass or alteration in function. On sonography, juvenile xanthogranuloma appeared hypoechoic. On contrast-enhanced CT, masses appeared homogeneous and isoattenuating with muscle and sometimes eroded bone. On MR imaging, compared with the cerebral cortex, the masses appeared hyper- or isointense on T1 and hypo- or isointense on T2, had decreased diffusivity, and enhanced homogeneously. Juvenile xanthogranuloma was not included in the differential diagnosis in any case. CONCLUSIONS: Head and neck juvenile xanthogranuloma has varied manifestations. Mild hyperintensity on T1, hypointensity on T2 compared with the cerebral cortex, decreased diffusivity, and homogeneous enhancement are characteristic. Awareness of these features should prompt radiologists to include juvenile xanthogranuloma in the differential diagnosis of pediatric head and neck masses.

Imaging characteristics of cerebrovascular arteriopathy and stroke in Hutchinson-Gilford progeria syndrome.

BACKGROUND AND PURPOSE: HGPS is a rare disorder of segmental aging, with early morbidity from cardiovascular and cerebrovascular disease. The goal of this study was to identify the neurovascular features, infarct type, topography, and natural history of stroke in the only neurovascular imaging cohort study of HGPS. MATERIALS AND METHODS: We studied 25 children with confirmed diagnoses of HGPS and neuroimaging studies available for review. Relevant clinical information was abstracted from medical records. RESULTS: We identified features suggestive of a vasculopathy unique to HGPS, including distinctive intracranial steno-occlusive arterial lesions, basal cistern collateral vessels, and slow compensatory collateral flow over the cerebral convexities. The arterial pathology in the neck consisted of distal vertebral artery stenosis with prominent collateral vessel formation as well as stenosis and calcification of both the cervical internal and common carotid arteries. Radiographic evidence of infarction was found in 60% of patients, of which half were likely clinically silent. Both large- and small-vessel disease was observed, characterized by arterial territorial, white matter, lacunar, and watershed infarcts. CONCLUSIONS: We report a unique intracranial and superior cervical arteriopathy in HGPS distinct from other vasculopathies of childhood, such as Moyamoya, and cerebrovascular disease of aging, including atherosclerosis. Arterial features of the mid and lower neck are less distinctive. For the first time, we identified early and clinically silent strokes as a prevalent disease characteristic in HGPS. Longitudinal analysis of stroke incidence and vasculopathy may provide an outcome measure for future treatment interventions for children with HGPS.

Craniofacial abnormalities in Hutchinson-Gilford progeria syndrome.

HGPS is a rare syndrome of segmental premature aging. Our goal was to expand the scope of structural bone and soft-tissue craniofacial abnormalities in HGPS through CT or MR imaging. Using The Progeria Research Foundation Medical and Research Database, 98 imaging studies on 25 patients, birth to 14.1 years of age, were comprehensively reviewed. Eight newly identified abnormalities involving the calvaria, skull base, and soft tissues of the face and orbits were present with prevalences between 43% and 100%. These included J-shaped sellas, a mottled appearance and increased vascular markings of the calvaria, abnormally configured mandibular condyles, hypoplastic articular eminences, small zygomatic arches, prominent parotid glands, and optic nerve kinking. This expanded craniofacial characterization helps link disease features and improves our ability to evaluate how underlying genetic and cellular abnormalities culminate in a disease phenotype.

Surgical management of isolated hemangioblastomas of the spinal cord.

OBJECTIVE: Intramedullary hemangioblastomas are rare tumors, accounting for just 3% of all intraspinal neoplasms. The purpose of this study is to define the occurrence of isolated intramedullary hemangioblastomas and to analyze the role of the radiological studies and surgery for these lesions. METHODS: The charts of 19 consecutive patients operated on for isolated spinal intramedullary hemangioblastoma were reviewed. Preoperatively, all patients underwent magnetic resonance imaging and nine underwent spinal angiography. For all patients, the surgical approach was via posterior laminectomy. RESULTS: Our study sample comprised 6 women and 13 men, with an average age of 31.5 years (range, 16-75 yr). The mean prodrome was 20.8 months. Pain was the most common complaint. In all cases, the neoplasms were associated with a syrinx or edema. Gross total resection was achieved in all patients. At last follow-up examination (mean, 50.1 mo), 13 patients (68%) had improved and 6 patients (32%) had stabilized as compared with their preoperative clinical status. CONCLUSION: Isolated intramedullary hemangioblastomas typically have an indolent clinical course. These tumors have characteristic imaging properties on magnetic resonance imaging and angiography. Surgical removal of these lesions results in excellent long-term functional outcome.

Intraspinal clear cell meningioma: diagnosis and management: report of two cases.

OBJECTIVE AND IMPORTANCE: Intraspinal clear cell meningioma is a rare morphological variant of meningioma. Only 13 case reports are found in the literature; therefore, no management strategy has been defined for this tumor type. This article describes two patients, reviews the literature, and proposes a treatment plan for clear cell meningioma. CLINICAL PRESENTATION: Two female patients, 22 months and 8 years of age, respectively, presented with localized neck and leg pain that limited their ability to walk. Magnetic resonance imaging revealed intradural tumors, a cervical intramedullary neoplasm in the younger patient, and a cauda equina tumor in the older child. INTERVENTION: Both patients underwent radical resection of their intradural tumor. Both tumors, however, recurred shortly (5 and 6 mo) after the initial operation. During the second operation, a radical removal was performed on each patient. Both patients received adjuvant radiotherapy. In addition, the younger patient developed posterior fossa metastasis 20 months after intraspinal surgery. CONCLUSION: Intraspinal clear cell meningiomas are very uncommon tumors. The clinical course in our two patients supports the reported 40% recurrence rate within 15 months. These tumors also can disseminate within the central nervous system. We recommend serial imaging studies every 3 months. For recurrent tumors, we recommend localized radiation therapy after reoperation.

Radiologic features of pediatric thalamic and hypothalamic tumors.

A variety of histologic subtypes of tumor may affect the thalamus and the hypothalamus in the pediatric population. These tumors have radiologic features that are useful in predicting pathology. We discuss the radiologic findings of childhood thalamic and hypothalamic tumors and provide imaging examples.