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Markdown
429 lines
31 KiB
Markdown
---
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title: "Idiopathic Intracranial Hypertension"
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docid: "d7a0a1b6-1d94-473c-9fe9-021443969f9f"
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authors:
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- key: "a25c450b-3d34-4f64-bba3-cc0834813df6"
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value: "Miral D. Jhaveri, MD, MBA"
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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: "Diagnosis"
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slug: "diagnosis"
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treeNodeId: "51c00394-446e-4a38-94af-d3b1d14d34e8"
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-
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name: "Anatomy-Based Diagnoses"
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slug: "anatomy-based-diagnoses"
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treeNodeId: "529d3e33-f508-498c-bc70-cf962e81e629"
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-
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name: "Ventricles and Cisterns"
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slug: "ventricles-and-cisterns"
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treeNodeId: "33b267f0-908c-4c77-81f8-f6135d1bc592"
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-
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name: "CSF Disorders"
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slug: "csf-disorders"
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treeNodeId: "d305bd95-7cca-4888-80b9-fabe45d84ee5"
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-
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name: "Idiopathic Intracranial Hypertension"
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slug: "idiopathic-intracranial-hypertensi-"
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treeNodeId: null
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category: "Brain"
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documentVersionId: "8907806d-0770-46fa-b129-78e393ad4038"
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imageCount: 22
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lastUpdated: "10/08/20"
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pageDescription: "Idiopathic Intracranial Hypertension"
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pageKeywords: "Brain, Diagnosis, Anatomy-Based Diagnoses, Ventricles and Cisterns, CSF Disorders, Idiopathic Intracranial Hypertension"
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pageTitle: "Idiopathic Intracranial Hypertension | STATdx"
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enhancedTitle: "Idiopathic Intracranial Hypertension"
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type: "DX"
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references: true
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tables: 1
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breadcrumbs:
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- "Brain"
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- "Diagnosis"
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- "Anatomy-Based Diagnoses"
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- "Ventricles and Cisterns"
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- "CSF Disorders"
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- "Idiopathic Intracranial Hypertension"
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---
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# KEY FACTS
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- ## Terminology
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- Idiopathic intracranial hypertension (IIH)
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- Pseudotumor cerebri
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- Benign intracranial hypertension
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- ↑ intracranial pressure (ICP) without identifiable cause
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- ## Imaging
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- Empty or partially empty sella
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- Posterior globe flattening
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- Intraocular protrusion of optic nerve head
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- Optic nerve sheath enlargement ± tortuosity
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- Optic nerve head DWI hyperintensity, ± enhancement
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- Slit-like ventricles, rare: Poor neuroimaging sign of IIH
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- MRV: Often shows transverse sinus stenosis and flow gaps
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- Whether this is cause or consequence of raised ICP is controversial
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- Best imaging tool: MR brain + T2 coronal fat-saturated orbit + MRV
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- ## Top Differential Diagnoses
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- Secondary pseudotumor syndromes
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- Idiopathic or postinflammatory (i.e., multiple sclerosis) optic nerve atrophy
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- Idiopathic empty sella (normal variant)
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- Chiari 1 malformation
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- ## Clinical Issues
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- Obese woman age 20-44 years with headache and papilledema most common presentation
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- Headache in 75-94%
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- Papilledema (bilateral optic nerve head swelling) virtually universal
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- Progressive visual loss ± CNVI paresis, diplopia
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- Chief hazard: Vision loss from chronic papilledema
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- Treatment: Medical or surgical (lumbar puncture, shunt, optic nerve sheath fenestration)
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- Stent placement in transverse sinus stenosis with significant pressure differentials across stenosis (controversial)
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# TERMINOLOGY
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- ## Abbreviations
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- Idiopathic intracranial hypertension (IIH)
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- ## Synonyms
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- Pseudotumor cerebri
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- Benign intracranial hypertension
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- ## Definitions
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- ↑ intracranial pressure (ICP) without identifiable cause
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- Association of any medication or condition with IIH better termed "secondary intracranial hypertension"
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# IMAGING
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- ## General Features
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- ### Best diagnostic clue
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- Flattening of posterior sclera, intraocular optic nerve protrusion, enlarged optic nerve sheath, ↑ tortuosity of optic nerve, partially empty sella, and venous sinus stenosis in patient with clinical findings of IIH
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- Imaging in IIH
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- Exclude identifiable causes of ↑ ICP
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- Detect findings associated with IIH
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- ## CT Findings
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- ### NECT
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- Usually normal
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- Enlarged optic nerve sheaths ± empty sella
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- Less common: Slit ventricles
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- ### Bone CT
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- Solitary or multiple skull base osseous-dural defects
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- May see skull base foramina enlargement
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- ## MR Findings
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- ### T1WI
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- Partially empty sella turcica
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- Enlarged/tortuous optic nerve sheaths
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- Posterior sclera flattened
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- Small "pinched" ventricles
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- Midline sagittal: Cerebellar tonsillar ectopia may mimic Chiari malformation type 1
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- ### T2WI
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- Empty or partially empty sella
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- Posterior globe flattening
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- Intraocular protrusion of optic nerve head
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- Optic nerve sheath enlargement: Widened ring of CSF around optic nerve
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- Optic nerve tortuosity
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- Slit-like ventricles, rare: Poor neuroimaging sign of IIH
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- "Tight" subarachnoid spaces
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- Meningoencephaloceles
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- ### FLAIR
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- Contrast-enhanced 3D-FLAIR: Hyperintensity of optic nerve head sensitive for detection of papilledema in IIH
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- ### DWI
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- DWI hyperintensity of optic nerve head with papilledema
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- DTI: Optic disc fractional anisotropy (FA) low & mean diffusivity (MD) high in IIH
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- ### T1WI C+
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- Enhancement of optic nerve head
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- ### MRV
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- Often shows transverse sinus stenosis and flow gaps
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- Controversial whether this is cause or consequence of raised ICP
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- CTV helpful to differentiate hypoplastic sinus segment from thrombosis
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- ## Imaging Recommendations
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- ### Best imaging tool
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- MR brain + T2 coronal fat-saturated orbit + MRV
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# DIFFERENTIAL DIAGNOSIS
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- ## Secondary Intracranial Hypertension
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- Cerebral venous abnormalities
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- [Dural venous sinus thrombosis, bilateral jugular vein thrombosis, superior vena cava syndrome, arteriovenous fistula](/document/dural-sinus-thrombosis/4e81a1de-df92-4172-99ec-1377b0d9d188)
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- ↓ CSF absorption from previous intracranial infection or subarachnoid hemorrhage, hypercoagulable states
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- Ventriculomegaly more common
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- Medications and exposures
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- Tetracycline, minocycline, vitamin A, lithium, retinoids, anabolic steroids, withdrawal from chronic corticosteroids
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- Medical conditions
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- Endocrine disorders (Addison disease, hypoparathyroidism), hypercapnia, sleep apnea, SLE
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- [Idiopathic or Postinflammatory Optic Nerve Atrophy](/document/optic-neuritis/ac9c8fc9-33cd-4716-a509-2542ec5579ca)
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- Small optic nerves without scleral flattening
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- [Idiopathic Empty Sella](/document/empty-sella/39a0d2d1-1439-4558-8f5d-86a2a6d93e3a)
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- Normal variant; normal optic nerve sheaths
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- [Chiari 1 Malformation](/document/chiari-1-malformation/97837e15-0d39-4c87-8af0-028652b399a6)
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- Peg-like tonsils ≥ 5 mm below foramen magnum
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- Low cerebellar tonsils in IIH may mimic Chiari 1
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# PATHOLOGY
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- ## General Features
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- ### Etiology
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- Precise etiology of IIH unknown
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- 5 different proposed mechanisms resulting in ↑ ICP
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- ↑ cerebral volume
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- Possible etiology: ↑ interstitial fluid, ↑ blood volume, ↑ tissue volume
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- ↑ CSF volume
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- Possible etiology: ↑ CSF production rate, ↑ CSF outflow resistance
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- ↑ cerebral arterial pressure
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- Possible etiology: Loss of cerebral autoregulation
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- ↑ venous blood volume and interstitial fluid
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- Possible etiology: ↑ cerebral venous pressure
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- ↓ CSF outflow and ↑ CSF volume
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- ## Gross Pathologic & Surgical Features
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- Bilateral papilledema
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- ## Microscopic Features
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- Normal CSF cytology, chemistry
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# CLINICAL ISSUES
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- ## Presentation
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- ### Most common signs/symptoms
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- Headache in 75-94%
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- Generalized, episodic, throbbing, aggravated by Valsalva
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- Transient vision loss, other visual complaints
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- Fulminant IIH, severe vision loss < 4 weeks from onset of symptoms
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- Papilledema (bilateral optic nerve head swelling) virtually universal
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- Progressive visual loss ± CNVI paresis, diplopia
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- Vertigo, tinnitus (52-60%), occasional pituitary dysfunction
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- May present with spontaneous CSF leak
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- Some patient with spontaneous CSF leak may not exhibit typical symptoms of IIH
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- May develop symptoms of IIH after CSF leak repair
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- Temporal lobe epilepsy caused by anteroinferior temporal lobe meningoencephaloceles in IIH
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- ### Clinical profile
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- Obese, young to middle-aged woman with headache, papilledema
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- ## Demographics
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- ### Age
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- Peak: 15-40 years (occasionally seen in children)
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- ### Epidemiology
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- 0.9 cases per 100,000 population in USA
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- More common in overweight, reproductive-aged women
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- Incidence in females aged 2-44 years & 20% above ideal body weight: ~ 19.3 cases per 100,000 population
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- ### Sex
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- M:F = 1:8
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- Epidemiology: ↑ prevalence with obesity
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- ## Natural History & Prognosis
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- Chief hazard: Vision loss from chronic papilledema, severe visual acuity deficits in 25% of patients without treatment
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- ## Treatment
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- Goal: Prevent visual loss, improve associated symptoms
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- Options
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- Medical: Weight loss, carbonic anhydrase inhibitors: Acetazolamide
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- Therapeutic lumbar puncture
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- Surgical: Reserved for patients who continue to experience vision loss despite conservative management and those initially presenting with rapid vision loss
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- Lumboperitoneal shunt, optic nerve sheath fenestration
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- Venous stent placement
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- Stent placement in transverse sinus stenosis with significant pressure differentials across stenosis has shown to improve symptoms and ↓ papilledema
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- ↓ cerebral venous pressure, improve CSF resorption in venous system: ↓ intracranial (CSF) pressure, improving symptoms of IIH, and ↓ papilledema
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- **Venous stent placement is controversial**
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# DIAGNOSTIC CHECKLIST
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- ## Image Interpretation Pearls
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- Must exclude venous thrombosis/space-occupying lesion
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58e13d74-efc9-4630-9014-3c28122c7470
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## References
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# Selected References
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1. [Nagarajan E et al: Is magnetic resonance imaging diffusion restriction of the optic disc head a new marker for idiopathic intracranial hypertension? J Neurosci Rural Pract. 11(1):170-4, 2020](http://www.ncbi.nlm.nih.gov/pubmed/?term=32140023%5Bpmid%5D)
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1. [Boyter E: Idiopathic intracranial hypertension. JAAPA. 32(5):30-5, 2019](http://www.ncbi.nlm.nih.gov/pubmed/?term=30969189%5Bpmid%5D)
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1. [Golden E et al: Contrast-enhanced 3D-FLAIR imaging of the optic nerve and optic nerve head: novel neuroimaging findings of idiopathic intracranial hypertension. AJNR Am J Neuroradiol. 40(2):334-9, 2019](http://www.ncbi.nlm.nih.gov/pubmed/?term=30679213%5Bpmid%5D)
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1. [Rehder D: Idiopathic intracranial hypertension: review of clinical syndrome, imaging findings, and treatment. Curr Probl Diagn Radiol. ePub, 2019](http://www.ncbi.nlm.nih.gov/pubmed/?term=31056359%5Bpmid%5D)
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1. [Thurtell MJ: Idiopathic intracranial hypertension. Continuum (Minneap Minn). 25(5):1289-309, 2019](http://www.ncbi.nlm.nih.gov/pubmed/?term=31584538%5Bpmid%5D)
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1. [Madriz Peralta G et al: An update of idiopathic intracranial hypertension. Curr Opin Ophthalmol. 29(6):495-502, 2018](http://www.ncbi.nlm.nih.gov/pubmed/?term=30169466%5Bpmid%5D)
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1. [Stevens SM et al: Idiopathic intracranial hypertension: contemporary review and implications for the otolaryngologist. Laryngoscope. 128(1):248-56, 2018](http://www.ncbi.nlm.nih.gov/pubmed/?term=28349571%5Bpmid%5D)
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1. [Wall M: Update on idiopathic intracranial hypertension. Neurol Clin. 35(1):45-57, 2017](http://www.ncbi.nlm.nih.gov/pubmed/?term=27886895%5Bpmid%5D)
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1. [Görkem SB et al: MR imaging findings in children with pseudotumor cerebri and comparison with healthy controls. Childs Nerv Syst. 31(3):373-80, 2015](http://www.ncbi.nlm.nih.gov/pubmed/?term=25358812%5Bpmid%5D)
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1. [Masri A et al: Intracranial hypertension in children: etiologies, clinical features, and outcome. J Child Neurol. 30(12):1562-8, 2015](http://www.ncbi.nlm.nih.gov/pubmed/?term=25762586%5Bpmid%5D)
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1. [Sivasankar R et al: Imaging and interventions in idiopathic intracranial hypertension: a pictorial essay. Indian J Radiol Imaging. 25(4):439-44, 2015](http://www.ncbi.nlm.nih.gov/pubmed/?term=26752823%5Bpmid%5D)
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1. [Ahmed RM et al: Transverse sinus stenting for pseudotumor cerebri: a cost comparison with CSF shunting. AJNR Am J Neuroradiol. 35(5):952-8, 2014](http://www.ncbi.nlm.nih.gov/pubmed/?term=24287092%5Bpmid%5D)
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1. [Dave SB et al: Pseudotumor cerebri: an update on treatment options. Indian J Ophthalmol. 62(10):996-8, 2014](http://www.ncbi.nlm.nih.gov/pubmed/?term=25449933%5Bpmid%5D)
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1. [Liguori C et al: Revised diagnostic criteria for the pseudotumor cerebri syndrome in adults and children. Neurology. 82(19):1752-3, 2014](http://www.ncbi.nlm.nih.gov/pubmed/?term=24821936%5Bpmid%5D)
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1. [Friedman DI et al: Revised diagnostic criteria for the pseudotumor cerebri syndrome in adults and children. Neurology. 81(13):1159-65, 2013](http://www.ncbi.nlm.nih.gov/pubmed/?term=23966248%5Bpmid%5D)
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1. [Passi N et al: MR imaging of papilledema and visual pathways: effects of increased intracranial pressure and pathophysiologic mechanisms. AJNR Am J Neuroradiol. 34(5):919-24, 2013](http://www.ncbi.nlm.nih.gov/pubmed/?term=22422187%5Bpmid%5D)
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1. [Aiken AH et al: Incidence of cerebellar tonsillar ectopia in idiopathic intracranial hypertension: a mimic of the Chiari I malformation. AJNR Am J Neuroradiol. 33(10):1901-6, 2012](http://www.ncbi.nlm.nih.gov/pubmed/?term=22723059%5Bpmid%5D)
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1. [Ahmed RM et al: Transverse sinus stenting for idiopathic intracranial hypertension: a review of 52 patients and of model predictions. AJNR Am J Neuroradiol. 32(8):1408-14, 2011](http://www.ncbi.nlm.nih.gov/pubmed/?term=21799038%5Bpmid%5D)
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1. [Degnan AJ et al: Pseudotumor cerebri: brief review of clinical syndrome and imaging findings. AJNR Am J Neuroradiol. 32(11):1986-93, 2011](http://www.ncbi.nlm.nih.gov/pubmed/?term=21680652%5Bpmid%5D)
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1. [Furtado SV et al: Pseudotumor cerebri: as a cause for early deterioration after Chiari I malformation surgery. Childs Nerv Syst. 25(8):1007-12, 2009](http://www.ncbi.nlm.nih.gov/pubmed/?term=19296114%5Bpmid%5D)
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1. [Hershko AY et al: Increased intracranial pressure related to systemic lupus erythematosus: a 26-year experience. Semin Arthritis Rheum. 38(2):110-5, 2008](http://www.ncbi.nlm.nih.gov/pubmed/?term=18221986%5Bpmid%5D)
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1. [Randhawa S et al: Idiopathic intracranial hypertension (pseudotumor cerebri). Curr Opin Ophthalmol. 19(6):445-53, 2008](http://www.ncbi.nlm.nih.gov/pubmed/?term=18854688%5Bpmid%5D)
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1. [Agarwal MR et al: Optic nerve sheath fenestration for vision preservation in idiopathic intracranial hypertension. Neurosurg Focus. 23(5):E7, 2007](http://www.ncbi.nlm.nih.gov/pubmed/?term=18004969%5Bpmid%5D)
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1. [Binder DK et al: Idiopathic intracranial hypertension. Neurosurgery. 54(3):538-51; discussion 551-2, 2004](http://www.ncbi.nlm.nih.gov/pubmed/?term=15028127%5Bpmid%5D)
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1. [Bastin ME et al: Diffuse brain oedema in idiopathic intracranial hypertension: a quantitative magnetic resonance imaging study. J Neurol Neurosurg Psychiatry. 74(12):1693-6, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=14638893%5Bpmid%5D)
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1. [Bandyopadhyay S: Pseudotumor cerebri. Arch Neurol. 58(10):1699-701, 2001](http://www.ncbi.nlm.nih.gov/pubmed/?term=11594936%5Bpmid%5D)
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1. [Suzuki H et al: MR imaging of idiopathic intracranial hypertension. AJNR Am J Neuroradiol. 22(1):196-9, 2001](http://www.ncbi.nlm.nih.gov/pubmed/?term=11158909%5Bpmid%5D)
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## Tables
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# Original Modified Dandy Criteria and Criteria Utilized in IIH Treatment Trial
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| A: Modified Dandy Criteria for IIH |
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| --- |
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| (1) Signs and symptoms of ↑ ICP (headaches, nausea, vomiting, transient visual obscurations, or papilledema) |
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| (2) Absence of localized findings in neurologic examination (except for false localizing signs, such as abducens nerve palsy) |
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| (3) Normal CT/MR findings without evidence of hydrocephalus or mass lesion |
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| (4) CSF opening pressure > 25 cm with normal CSF cytologic and chemical findings |
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| (5) No other causes of ↑ ICP identified |
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| B: Idiopathic IIH Treatment Trial: Modified Dandy Criteria |
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| (1) Signs and symptoms of ↑ ICP |
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| (2) Absence of localized findings in neurologic examination |
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| (3) ↑ CSF pressure > 20 cm; normal neuroimaging except for empty sella, flattening optic nerve head, distention of perioptic subarachnoid space ± tortuous optic nerve, transverse venous sinus stenosis |
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| (4) Awake and alert |
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| (5) No other causes of ↑ ICP |
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| If CSF opening pressure was 20-25 cm, at least 1 of following was also required |
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| Pulse synchronous tinnitus, CNVI palsy, Frisen grade II papilledema, no disc anomalies mimicking disc edema, MRV with lateral sinus collapse/stenosis, partially empty sella, dilated optic nerve sheaths |
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## Images
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### Selected Images
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*Axial T2 FS MR in a young obese female with headaches and visual symptoms shows flattening of the posterior sclera <img src='img/arrows/CS.png'/> and minimal protrusion of the optic nerve papilla <img src='img/arrows/CC.png'/> into the posterior globe. Note mild prominence of the CSF <img src='img/arrows/CO.png'/> along the optic nerve sheaths.*
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*Axial T2 FS MR in a young obese female with headaches and visual symptoms shows flattening of the posterior sclera <img src='img/arrows/CS.png'/> and minimal protrusion of the optic nerve papilla <img src='img/arrows/CC.png'/> into the posterior globe. Note mild prominence of the CSF <img src='img/arrows/CO.png'/> along the optic nerve sheaths.*
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*Axial DWI in the same patient demonstrates subtle high signal <img src='img/arrows/CS.png'/> in the region of the optic nerve heads bilaterally. Hyperintensity of the optic nerve heads on DWI can serve as a useful imaging marker for papilledema, especially if bilateral.*
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*Axial T1 C+ MR in the same patient shows subtle enhancement <img src='img/arrows/CC.png'/>, as well as protrusion of prelaminar optic nerves bilaterally.*
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*Coronal T2 FS MR in the same patient shows a partially empty sella <img src='img/arrows/CC.png'/> with the pituitary gland <img src='img/arrows/CS.png'/> flattened along the floor of the sella. Idiopathic intracranial hypertension is more commonly observed in overweight women of reproductive age. Treatment includes weight loss and medications, as well as lumbar punctures, shunt, and optic nerve fenestration.*
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*Coronal T2 FS MR of orbits in a 6 year old with papilledema and opening CSF pressure of 32 cm of H₂O shows dilated optic nerve sheaths bilaterally <img src='img/arrows/CC.png'/>.*
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*Sagittal T2 FS MR in the same patient shows tortuosity of the optic nerve, dilated optic nerve sheath <img src='img/arrows/WS.png'/>, flattening of the posterior sclera <img src='img/arrows/CC.png'/>, and mild bulging of the optic nerve disc head <img src='img/arrows/CS.png'/> due to papilledema. Findings are typical of idiopathic intracranial hypertension (IIH). Childhood obesity has a strong association with ↑ risk of pediatric IIH.*
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*Sagittal T2 MR in a young female with IIH and temporal lobe epilepsy shows a defect <img src='img/arrows/CS.png'/> along the floor of the middle cranial fossa with herniation of the anteroinferior temporal lobe <img src='img/arrows/CC.png'/>.*
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*Coronal CT cisternogram in a patient with IIH shows an osteodural defect <img src='img/arrows/CC.png'/> along the great wing of the sphenoid. Defect along the lateral wall of the sphenoid sinus <img src='img/arrows/CS.png'/> with a meningocele and contrast <img src='img/arrows/CO.png'/> in the lateral sphenoid sinus due to CSF leak is shown. Patients with IIH can present with spontaneous CSF leaks.*
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*MIP image of a postcontrast MR venogram study in a patient with IIH shows stenosis of the distal transverse sinuses bilaterally <img src='img/arrows/CS.png'/>, right > left.*
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*3D VRT MR in the same patient shows transverse sinus stenosis <img src='img/arrows/CC.png'/>, right > left. Phase contrast and postcontrast MR venogram techniques are preferred over TOF-MR venogram to evaluate for transverse sinus stenosis. Stenting of transverse sinus stenosis in patients with IIH is a controversial treatment option.*
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### Additional Images
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*Coronal T1WI MR in the same patient shows unusually small lateral ventricles with a "pinched" appearance. These findings in an obese female with headaches and papilledema are consistent with IIH.*
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*Axial T2WI MR shows ↑ fluid in bilateral optic nerve sheaths with mild flattening of the globes at optic nerve insertion. Also note the CSF-filled and expanded empty sella <img src='img/arrows/BS.png'/>.*
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*Sagittal T1WI MR in another patient with IIH ("pseudotumor cerebri") shows empty sella <img src='img/arrows/BC.png'/>. The ventricular size is normal.*
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*Axial T2WI MR shows ↑ fluid in the sheaths surrounding the optic nerves <img src='img/arrows/WC.png'/>, associated with severe scleral flattening <img src='img/arrows/BO.png'/>.*
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*Axial T2WI MR shows dilated CSF spaces around the optic nerves <img src='img/arrows/WO.png'/> and protrusion of the optic nerve papilla into the posterior globes <img src='img/arrows/WC.png'/>. Opening CSF pressure in this 32-year-old woman was 45 cm of H₂O. Prominent CSF space in the suprasellar cistern represents an empty sella <img src='img/arrows/WS.png'/>. Note the tortuosity of the left optic nerve.*
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*Sagittal T1WI MR in the same patient shows a partially empty sella <img src='img/arrows/WS.png'/>, suggesting high CSF pressure in this young obese woman with headaches.*
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*Axial T1WI C+ MR in the same patient demonstrates enhancement, as well as protrusion of prelaminar optic nerves bilaterally <img src='img/arrows/WC.png'/>. Mild diffuse optic nerve sheath enhancement is also present.*
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*Coronal T1WI C+ FS MR in the same patient shows diffuse enhancement of the optic nerve sheaths <img src='img/arrows/WC.png'/> associated with prominent subarachnoid spaces along the optic nerves. Treatment for pseudotumor cerebri includes weight loss and medications, as well as lumbar punctures, shunt, and optic nerve fenestration.*
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*Sagittal T1 MR in a patient with IIH shows a partially empty sella <img src='img/arrows/CC.png'/> with the pituitary gland <img src='img/arrows/CS.png'/> flattened along the floor of the sella.*
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*MIP image of a postcontrast MR venogram study in the same patient shows stenosis of the distal transverse sinuses bilaterally <img src='img/arrows/CS.png'/>. Transverse sinus stenosis is common in patients with IIH.*
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*Axial T2WI MR in a young obese female with headaches and visual symptoms shows mild dilatation of the CSF spaces <img src='img/arrows/CS.png'/> around the optic nerves. There is mild flattening of the posterior sclera <img src='img/arrows/CC.png'/> and minimal protrusion of the optic nerve papilla <img src='img/arrows/CO.png'/> into the posterior globe.*
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*3D TOF-MR venogram image in the same patient shows stenosis in the distal transverse sinuses bilaterally <img src='img/arrows/CC.png'/>. Stent placement in sinus stenosis with significant pressure differentials has shown to reduce papilledema.*
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