339 lines
33 KiB
Markdown
339 lines
33 KiB
Markdown
---
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title: "Cyst With Nodule"
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docid: "6cb71737-f574-4121-a8fb-02eeada9f9f7"
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authors:
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- key: "4b6589b0-9b8d-4467-8a90-01a0a59742fc"
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value: "Troy A. Hutchins, MD"
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- key: "8d5254e9-8dda-478b-8f08-bdee97a32c79"
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value: "Karen L. Salzman, MD, FACR"
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breadcrumbs:
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-
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name: "Brain"
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slug: "brain"
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treeNodeId: "6d8829f1-14d7-45af-8675-255189aa526a"
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-
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name: "Differential Diagnosis"
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slug: "differential-diagnosis"
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treeNodeId: "a7fdd139-664e-4bb8-8d18-400e4733ff60"
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-
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name: "Brain Parenchyma, General"
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slug: "brain-parenchyma-general"
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treeNodeId: "e79be97b-28c0-4023-be87-334c0579d35d"
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-
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name: "Generic Imaging Patterns"
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slug: "generic-imaging-patterns"
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treeNodeId: "66ab9cf6-74ad-42b7-a40a-4b6224edaa25"
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-
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name: "Cyst With Nodule"
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slug: "cyst-with-nodule"
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treeNodeId: null
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category: "Brain"
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documentVersionId: "a8a6b610-83a2-461f-bc34-b34af327c00c"
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imageCount: 35
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lastUpdated: "03/14/23"
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pageDescription: "Cyst With Nodule"
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pageKeywords: "Brain, Differential Diagnosis, Brain Parenchyma, General, Generic Imaging Patterns, Cyst With Nodule"
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pageTitle: "Cyst With Nodule | STATdx"
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enhancedTitle: "Cyst With Nodule"
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type: "DDX"
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references: true
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breadcrumbs:
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- "Brain"
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- "Differential Diagnosis"
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- "Brain Parenchyma, General"
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- "Generic Imaging Patterns"
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- "Cyst With Nodule"
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---
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# ESSENTIAL INFORMATION
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- ## Key Differential Diagnosis Issues
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- Cystic lesions with solid nodular components can be divided into 2 categories
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- Lesions that typically demonstrate cyst with nodule morphology
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- Neurocysticercosis (NCC), pilocytic astrocytoma, ganglioglioma, hemangioblastoma, pleomorphic xanthoastrocytoma (PXA), desmoplastic infantile ganglioglioma (DIG), intraparenchymal schwannoma
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- Lesions that may demonstrate cyst with nodule morphology
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- Metastases, glioblastoma (GBM), abscess, toxoplasmosis, parasites, dysplastic neuroepithelial tumor (DNET), thrombosed arteriovenous malformation (AVM), supratentorial ependymoma
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- Although metastases, abscesses, & GBMs do not classically present as "cysts with nodules," they are included because of their overall prevalence
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- Statistically, atypical form of these common diseases may be more likely than some of other "classic" cysts with nodule lesions
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- ## Helpful Clues for Common Diagnoses
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- **Neurocysticercosis**
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- Intracranial parasitic infection caused by pork tapeworm *Taenia solium*
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- Cyst with "dot" inside representing scolex
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- Imaging appearance varies with stage; increased enhancement & edema when organism dies (inflammatory host response)
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- Location: Convexity subarachnoid space > > cisterns > parenchyma > ventricles
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- Lesions may be at different stages in same patient
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- **Pilocytic Astrocytoma**
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- Cerebellar cystic mass with mural nodule in child; rarely supratentorial
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- T1 C+ MR: Nodule shows intense but heterogeneous enhancement
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- Cyst wall may show enhancement
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- T1 & T2 MR: Cyst content iso- to hyperintense to CSF
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- Most common brain tumor in children
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- **Ganglioglioma**
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- Cortically based, slow-growing, enhancing mass in older child or young adult
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- Circumscribed cyst with mural nodule most common
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- May be solid and appear well circumscribed
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- Often expands cortex; calcification common
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- Most common tumor to cause temporal lobe epilepsy
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- Cortical dysplasia is commonly associated
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- **Hemangioblastoma**
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- Vascular neoplasm of uncertain etiology
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- Parenchymal posterior fossa cyst with nodule mass in adult
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- T1 C+ MR: Nodule abuts pial surface & shows intense, homogeneous enhancement
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- Prominent flow voids may be seen
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- Multiple in von Hippel-Lindau syndrome (VHL) (25-40% of hemangioblastomas)
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- ## Helpful Clues for Less Common Diagnoses
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- **Metastases, Parenchymal**
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- Discrete, gray-white interface mass(es) with adjacent vasogenic edema
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- Multiplicity, history of primary malignancy helpful if present
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- Solitary metastasis may mimic GBM
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- Often known history of primary neoplasm
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- **Glioblastoma, IDH-Wildtype**
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- Malignant white matter mass with central necrosis
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- Predilection to spread across midline along corpus callosum; "butterfly glioma"
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- T1 C+ MR: Thick, irregular, nodular, enhancing margins
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- T2/FLAIR MR: Surrounding hyperintensity & mass effect reflect edema + infiltrative tumor
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- **Pleomorphic Xanthoastrocytoma**
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- Cortically based cyst + nodule ± involvement of adjacent meninges
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- T1 C+ MR
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- Enhancing nodule
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- Thickening, enhancement of adjacent meninges
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- 70% have dural tail
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- Temporal lobe predominance; young adult
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- Maybe associated with cortical dysplasia
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- **Abscess**
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- T2 MR: Hypointense rim with surrounding edema classic
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- T1 C+ MR: Enhancing capsule thinnest at ventricular side
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- DWI MR: Cystic component bright (diffusion restriction)
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- SWI MR: Dual rim sign (hypointense outside, hyperintense inside )
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- **Opportunistic Infection, AIDS, Toxoplasmosis**
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- Caused by parasite *Toxoplasma gondii*
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- Toxoplasmosis: Ring-enhancing lesion containing eccentric nodule = eccentric target sign specific but not sensitive
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- Location: Basal ganglia > hemispheres
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- Clinical: Immunocompromised patient
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- **Parasites, Miscellaneous**
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- Multiple enhancing lesions typical
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- May mimic brain tumor
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- Travel history critical
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- **Dysplastic Neuroepithelial Tumor**
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- Bubbly, wedge-shaped, cortically based mass "points" toward lateral ventricle
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- T2 MR: Very hyperintense; nodular, septate; no surrounding edema
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- FLAIR MR: Hyperintense ring sign
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- Thin rim of well-defined peritumoral hyperintensity separating it from surrounding normal brain
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- T1 C+ MR: No to minimal enhancement; may be nodular
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- Temporal lobe predominance
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- ## Helpful Clues for Rare Diagnoses
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- **Desmoplastic Infantile Ganglioglioma**
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- Supratentorial cystic/nodular mass with dominance of cyst
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- Cortically based nodule with intense enhancement & dural tail
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- May be massive
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- Peak age: 3-6 months
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- **Schwannoma, Intraparenchymal**
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- Only 1-2% of schwannomas are parenchymal
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- Cyst with strongly enhancing nodule
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- **Arteriovenous Malformation**
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- When hemorrhagic with partial or complete thrombosis, may present as cyst with nodule
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- Blood breakdown products of various ages; fluid-fluid levels
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- **Ependymoma, Supratentorial**
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- 40% of supratentorial ependymomas are extraventricular
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- Large, complex, mixed solid/cystic mass
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- Calcification, intratumoral hemorrhage common
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- Moderate but inhomogeneous enhancement
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- **Meningioma (Cystic)**
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- Meningioma with intraparenchymal cyst may mimic cyst + nodule mass
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- **Rosette-Forming Glioneuronal Tumor**
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- Rare, slowly growing benign tumor of young adults
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- 4th ventricle most common site > cerebellum
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- Mixed solid-cystic appearance, variable Ca⁺⁺, hemorrhage
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- May show cyst with nodule configuration
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- **Papillary Glioneuronal Tumor**
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- Temporal lobe predilection
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- Parenchymal mass with solid, cystic, or cyst/mural nodule architecture
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- May show calcification
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- Imaging may be indistinguishable from ganglioglioma
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- ## Alternative Differential Approaches
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- By location
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- Posterior fossa: Pilocytic astrocytoma, hemangioblastoma, metastasis, Rosette-forming glioneuronal tumor
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- Temporal lobe: Ganglioglioma, PXA, DNET, papillary glioneuronal tumor
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- Gray-white junction: Metastases, abscess
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- Hemispheric: NCC, metastases, GBM, infections, DIG, AVM, supratentorial ependymoma
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- Patient age
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- Child & young adult: Pilocytic astrocytoma, ganglioglioma, PXA, DNET
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- Adult: Hemangioblastoma, GBM, metastases
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- Any age: NCC, abscess, other infections
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- Multiple lesions
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- Metastases (50-55%), NCC (50-70%), hemangioblastoma (VHL), abscesses (septic emboli), toxoplasmosis, parasites
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## References
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# Selected References
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1. [Sotoudeh H et al: Radiomics for differentiation of the posterior fossa pilocytic astrocytoma versus hemangioblastomas in adults. A pilot study. Clin Imaging. 93:26-30, 2022](http://www.ncbi.nlm.nih.gov/pubmed/?term=36370592%5Bpmid%5D)
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1. [Medhi G et al: Imaging features of rosette-forming glioneuronal tumours (RGNTs): a series of seven cases. Eur Radiol. 26(1):262-70, 2016](http://www.ncbi.nlm.nih.gov/pubmed/?term=26017735%5Bpmid%5D)
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1. [Carangelo B et al: Papillary glioneuronal tumor: case report and review of literature. G Chir. 36(2):63-9, 2015](http://www.ncbi.nlm.nih.gov/pubmed/?term=26017104%5Bpmid%5D)
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1. [Raz E et al: Cyst with a mural nodule tumor of the brain. Cancer Imaging. 12:237-44, 2012](http://www.ncbi.nlm.nih.gov/pubmed/?term=22935908%5Bpmid%5D)
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1. [Kumar GG et al: Eccentric target sign in cerebral toxoplasmosis: neuropathological correlate to the imaging feature. J Magn Reson Imaging. 31(6):1469-72, 2010](http://www.ncbi.nlm.nih.gov/pubmed/?term=20512900%5Bpmid%5D)
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1. [Smirniotopoulos JG et al: Patterns of contrast enhancement in the brain and meninges. Radiographics. Mar-Apr;27(2):525-51, 2007](http://www.ncbi.nlm.nih.gov/pubmed/?term=17374867%5Bpmid%5D)
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## Images
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### Selected Images
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**Neurocysticercosis**
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*Axial FLAIR MR demonstrates a neurocysticercosis cyst <img src='img/arrows/WC.png'/> with an eccentric nodule (scolex) <img src='img/arrows/WS.png'/>. Additional lesions have surrounding edema <img src='img/arrows/WO.png'/>. Edema and enhancement vary with the stage of neurocysticercosis and host response.*
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**Neurocysticercosis**
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*Axial FLAIR MR demonstrates a neurocysticercosis cyst <img src='img/arrows/WC.png'/> with an eccentric nodule (scolex) <img src='img/arrows/WS.png'/>. Additional lesions have surrounding edema <img src='img/arrows/WO.png'/>. Edema and enhancement vary with the stage of neurocysticercosis and host response.*
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**Pilocytic Astrocytoma**
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*Axial T1 C+ SPGR MR shows a pilocytic astrocytoma with enhancing, eccentric nodule <img src='img/arrows/WO.png'/>. There is cyst wall enhancement <img src='img/arrows/WC.png'/> (present in ~ 50% of cases). Note obstructive hydrocephalus with dilation of superior 4th ventricle <img src='img/arrows/WS.png'/> secondary to mass effect.*
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**Ganglioglioma**
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*Coronal T1 C+ MR in a young adult patient with epilepsy shows a cystic and solid mass in the temporal lobe with intense enhancement of the solid mural nodule <img src='img/arrows/WS.png'/>. Gangliogliomas are the most common tumor to cause temporal lobe epilepsy.*
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**Hemangioblastoma**
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*Coronal T1 C+ MR in an adult patient reveals a cystic mass with an intensely enhancing mural nodule <img src='img/arrows/WC.png'/> in the posterior fossa. Additional enhancing nodules <img src='img/arrows/WS.png'/> are noted in this patient with von Hippel-Lindau.*
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**Metastases, Parenchymal**
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*Coronal T1 C+ MR in a patient with primary malignancy demonstrates a cystic and solid, enhancing, nodular mass <img src='img/arrows/WO.png'/> with the surrounding vasogenic edema <img src='img/arrows/WC.png'/>. Multiple additional lesions <img src='img/arrows/WS.png'/> and clinical history can help with diagnosis.*
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**Glioblastoma, IDH-Wildtype**
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*Axial T1 C+ FS MR shows an infiltrative left frontal lobe glioblastoma with cystic <img src='img/arrows/WS.png'/> and heterogeneously enhancing, solid, nodular <img src='img/arrows/WC.png'/> components. Glioblastomas have a predilection for crossing midline through the corpus callosum.*
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**Pleomorphic Xanthoastrocytoma**
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*Coronal T1 C+ MR shows a cortically based left temporal lobe cystic mass <img src='img/arrows/CO.png'/> with an enhancing nodule <img src='img/arrows/CC.png'/> in a young adult. Enhancement & thickening of the adjacent dura <img src='img/arrows/CS.png'/> help diagnose PXA & differentiate from a ganglioglioma.*
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**Abscess**
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*Sagittal T1 C+ MR in a patient treated for sinusitis who presented with headache, fever, and seizures shows a large, ring-enhancing abscess <img src='img/arrows/CC.png'/> with an eccentric nodule <img src='img/arrows/CO.png'/>. DWI (not shown) showed characteristic diffusion restriction in the central nonenhancing component.*
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**Opportunistic Infection, AIDS, Toxoplasmosis**
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*Axial T1 C+ FS MR in an immunocompromised patient shows a ring-enhancing lesion with peripheral enhancing nodule <img src='img/arrows/WC.png'/>. This eccentric target sign is specific but not sensitive for toxoplasmosis. Note the numerous additional nodular and ring-enhancing lesions <img src='img/arrows/WS.png'/> and surrounding edema <img src='img/arrows/WO.png'/>.*
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**Parasites, Miscellaneous**
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*Axial CECT demonstrates a ring-enhancing lesion with an associated nodule <img src='img/arrows/CC.png'/> and surrounding vasogenic edema. Multiple punctate lesions <img src='img/arrows/CS.png'/> are also apparent in this patient with amebic encephalitis.*
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**Dysplastic Neuroepithelial Tumor**
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*Axial T1 C+ MR in a patient with epilepsy shows a cortically based, bubbly, cystic mass <img src='img/arrows/CC.png'/> with an eccentric, enhancing nodule <img src='img/arrows/CO.png'/>. Faint, nodular enhancement can be seen in 20% of DNETs. FLAIR images often show a well-defined, hyperintense ring surrounding the mass.*
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**Desmoplastic Infantile Ganglioglioma**
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*Coronal T1 C+ MR shows a large cyst <img src='img/arrows/CS.png'/> with a cortically based, intensely enhancing mural nodule <img src='img/arrows/WS.png'/> in an infant. Note the adjacent dural thickening & enhancement <img src='img/arrows/CC.png'/>, typical of desmoplastic infantile ganglioglioma.*
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**Schwannoma, Intraparenchymal**
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*Axial T1 C+ MR shows a cystic parenchymal mass <img src='img/arrows/CS.png'/> with an intensely enhancing mural nodule <img src='img/arrows/CO.png'/> in the right occipital lobe. Although ganglioglioma was the preoperative diagnosis, schwannoma was found on pathology.*
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**Ependymoma, Supratentorial**
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*Axial T2 MR shows a recurrent supratentorial ependymoma with a cyst <img src='img/arrows/WC.png'/> and nodule <img src='img/arrows/WS.png'/> architecture. 40% of supratentorial ependymomas are extraventricular. They are commonly associated with calcification and hemorrhage.*
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### Additional Images
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**Neurocysticercosis**
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*Axial FLAIR MR demonstrates a classic neurocysticercosis cyst <img src='img/arrows/CC.png'/> with an eccentric nodule (scolex) <img src='img/arrows/CS.png'/> in the right parietal lobe with surrounding vasogenic edema. The enhancement and edema varies with the stage of neurocysticercosis and host response.*
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**Neurocysticercosis**
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*Axial T1WI MR shows a frontal <img src='img/arrows/BC.png'/> & left lateral ventricular <img src='img/arrows/WO.png'/> "cyst with dot." The "dot" or scolex may be T1 hyperintense <img src='img/arrows/WC.png'/>. Edema & enhancement vary with stage & host response.*
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**Pilocytic Astrocytoma**
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*Axial T1 C+ MR shows a classic cerebellar pilocytic astrocytoma. There is well-defined enhancement of the cyst wall <img src='img/arrows/CS.png'/> with an enhancing eccentric nodule <img src='img/arrows/CO.png'/>. Note the mass effect on the 4th ventricle with obstructive hydrocephalus.*
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**Pilocytic Astrocytoma**
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*Axial T1 C+ MR shows a cystic mass <img src='img/arrows/WC.png'/> with an intense, heterogeneously enhancing mural nodule <img src='img/arrows/WO.png'/> in the posterior fossa of a child. Note associated temporal horn dilatation related to the tumor.*
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**Ganglioglioma**
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*Coronal T1 C+ MR in a child with epilepsy demonstrates a cystic and solid mass <img src='img/arrows/CO.png'/> in the temporal lobe with intense enhancement of the solid mural nodule <img src='img/arrows/CC.png'/>. Gangliogliomas commonly cause temporal lobe epilepsy.*
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**Ganglioglioma**
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*Coronal T1 C+ MR shows a circumscribed, cystic and solid mass in the temporal lobe with intense enhancement of the solid mural nodule <img src='img/arrows/WC.png'/>. Note cortical location and lack of significant mass effect and edema. Gangliogliomas commonly cause temporal lobe epilepsy.*
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**Hemangioblastoma**
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*Axial CECT in a middle-aged woman shows a cystic mass <img src='img/arrows/CC.png'/> with an intensely enhancing mural nodule <img src='img/arrows/CS.png'/> in the posterior fossa. Note extensive perilesional edema with mass effect and obstructive hydrocephalus. Histopathology revealed a hemangioblastoma.*
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**Hemangioblastoma**
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*Sagittal T1 C+ MR shows a cystic mass <img src='img/arrows/BC.png'/> with an intensely and homogeneously enhancing mural nodule <img src='img/arrows/BO.png'/> in the posterior fossa of an adult. The nodule typically abuts the pial surface.*
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**Metastases, Parenchymal**
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*Axial T1 C+ MR in a patient with breast carcinoma shows multiple metastatic lesions <img src='img/arrows/CC.png'/> in the posterior fossa with a few showing a cyst and nodule morphology.*
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**Metastases, Parenchymal**
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*Coronal T1 C+ MR shows a cystic mass with a large, enhancing nodule in the cerebellar hemisphere with rim enhancement <img src='img/arrows/WS.png'/>. This is an atypical appearance for a metastasis. History of primary malignancy & presence of other lesions are helpful for diagnosis.*
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**Metastases, Parenchymal**
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*Axial T1 C+ FS MR shows a "cystic" mass with nodular enhancement <img src='img/arrows/WC.png'/> in this patient with colon cancer. Multiple lesions and clinical history are helpful for diagnosis.*
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**Metastases, Parenchymal**
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*Coronal T1 C+ MR shows an irregularly enhancing perisylvian cystic & solid mass <img src='img/arrows/WO.png'/> in this patient with multiple lesions related to metastatic disease. Note the surrounding vasogenic edema in the frontal lobe.*
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**Glioblastoma, IDH-Wildtype**
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*Coronal T1 C+ MR shows a large, cystic mass with rim enhancement <img src='img/arrows/CS.png'/> and an intensely enhancing, eccentric nodule <img src='img/arrows/CC.png'/>. Note the mass effect with mild subfalcine herniation. Glioblastoma was the final pathology in this case.*
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**Glioblastoma, IDH-Wildtype**
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*Axial CECT shows a heterogeneous mass <img src='img/arrows/WS.png'/> with irregular peripheral enhancement containing a nodular component <img src='img/arrows/WC.png'/>. Aggressive features help diagnose this malignant tumor.*
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**Abscess**
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*Axial T1 C+ FS MR demonstrates a ring-enhancing lesion with a small, enhancing mural nodule <img src='img/arrows/WC.png'/>. DWI MR (not shown) showed characteristic diffusion restriction in the central nonenhancing component.*
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**Opportunistic Infection, AIDS, Toxoplasmosis**
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*Sagittal T1 C+ MR in an HIV-positive patient shows a ring-enhancing lesion <img src='img/arrows/CC.png'/> in the parietal lobe with marked perilesional edema. Note the target appearance with central nodule <img src='img/arrows/CS.png'/>, typical of toxoplasmosis.*
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**Opportunistic Infection, AIDS, Toxoplasmosis**
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*Coronal T1 C+ MR shows basal ganglia, thalamic, & parenchymal ring-enhancing lesions <img src='img/arrows/WS.png'/> in an immunocompromised patient. Note the target appearance with a central nodule <img src='img/arrows/BC.png'/> in the right temporal lobe lesion.*
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**Dysplastic Neuroepithelial Tumor**
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*Axial T2WI MR shows a wedge-shaped, extremely hyperintense, cortically based, bubbly mass <img src='img/arrows/WC.png'/> that "points" toward the lateral ventricle. Faint nodular enhancement can be seen in 20% of cases.*
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**Dysplastic Neuroepithelial Tumor**
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*Axial T1 C+ MR shows a left temporal lobe mass with a small focus of mild enhancement <img src='img/arrows/WS.png'/> within the bubbly, cystic mass. Faint nodular enhancement can be seen in 20% of DNETs. Lesions are typically T2 hyperintense & may erode the adjacent calvarium, as in this case.*
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**Ependymoma, Supratentorial**
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*Axial T2 MR shows a recurrent supratentorial ependymoma with a cyst <img src='img/arrows/CC.png'/> and nodule <img src='img/arrows/CO.png'/> architecture. NECT showed calcifications with the solid component. Note the old parietal craniotomy.*
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**Arteriovenous Malformation**
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*Axial CECT shows a mixed-density, cystic and solid lesion with rim enhancement <img src='img/arrows/WS.png'/>. There is a fluid-fluid level within 1 of the cysts <img src='img/arrows/WO.png'/>, representing hemorrhage in this partially thrombosed arteriovenous malformation.*
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