Book contents
- Frontmatter
- Dedication
- Contents
- Preface
- Case 1 Dense basilar artery sign
- Case 2 Global anoxic brain injury
- Case 3 Acute infarction
- Case 4 Vertebral artery dissection
- Case 5 Subacute infarct
- Case 6 Subarachnoid hemorrhage
- Case 7 Intracranial aneurysms
- Case 8 Giant aneurysms
- Case 9 Acute intracerebral hematoma
- Case 10 Cerebral amyloid angiopathy
- Case 11 Primary CNS vasculitis
- Case 12 Reversible cerebral vasoconstriction syndrome
- Case 13 Moyamoya disease/syndrome
- Case 14 Cortical venous thrombosis
- Case 15 Developmental venous anomalies
- Case 16 Dural arteriovenous fistula
- Case 17 Cavernous malformation
- Case 18 Tumefactive demyelinating lesion
- Case 19 Acute disseminated encephalomyelitis
- Case 20 Progressive multifocal leukoencephalopathy
- Case 21 Osmotic myelinolysis
- Case 22 Neurosarcoidosis
- Case 23 Posterior fossa masses in children
- Case 24 Low-grade glioma
- Case 25 Diffuse intrinsic pontine glioma
- Case 26 Pseudoprogression of GBM
- Case 27 Pseudoresponse in treatment of GBM
- Case 28 Low-grade oligodendroglioma
- Case 29 Primary CNS lymphoma
- Case 30 Pineal region tumors
- Case 31 Intraventricular masses
- Case 32 Colloid cyst
- Case 33 Primary intraosseous meningioma
- Case 34 Suprasellar meningioma
- Case 35 Pituitary macroadenoma
- Case 36 Brain abscess
- Case 37 Neurocysticercosis
- Case 38 Tuberculosis
- Case 39 Creutzfeldt–Jakob disease
- Case 40 Herpes encephalitis
- Case 41 Wernicke’s encephalopathy
- Case 42 Hypertrophic olivary degeneration
- Case 43 Adrenoleukodystrophy
- Case 44 Mild traumatic brain injury
- Case 45 Isodense subdural hematoma
- Case 46 Posterior reversible encephalopathy syndrome
- Case 47 Late-onset adult hydrocephalus secondary to aqueductal stenosis
- Case 48 Intracranial hypotension
- Case 49 Idiopathic intracranial hypertension
- Case 50 Rathke’s cleft cyst
- Case 51 FLAIR sulcal hyperintensity secondary to general anesthesia
- Case 52 Virchow–Robin spaces
- Case 53 Arachnoid granulations
- Case 54 Benign external hydrocephalus
- Case 55 Pitfalls in CTA
- Case 56 Asymmetric pneumatization of the anterior clinoid process
- Case 57 Fibrous dysplasia of skull base
- Case 58 Sphenoid bone pseudolesion
- Case 59 Clival lesions
- Case 60 Perineural spread
- Case 61 Cochlear dysplasia
- Case 62 Labyrinthitis ossificans
- Case 63 Superior semicircular canal dehiscence
- Case 64 Fluid entrapment in the petrous apex cells
- Case 65 Acquired cholesteatoma
- Case 66 Malignant otitis externa
- Case 67 Temporal bone fractures
- Case 68 Allergic fungal sinusitis
- Case 69 Invasive fungal sinusitis
- Case 70 Spontaneous CSF leaks and sphenoid cephaloceles
- Case 71 Juvenile nasal angiofibroma
- Case 72 Idiopathic orbital pseudotumor
- Case 73 Optic neuritis
- Case 74 Intraparotid lymph nodes
- Case 75 Benign mixed tumor
- Case 76 First branchial cleft cyst
- Case 77 Nasopharyngeal cysts
- Case 78 Cystic nodal metastasis
- Case 79 Low-flow vascular malformations
- Case 80 Parapharyngeal masses
- Case 81 Third branchial apparatus anomaly
- Case 82 Parathyroid adenoma
- Case 83 String sign
- Case 84 Carotid artery dissection
- Case 85 Traumatic arterial injury
- Case 86 Craniovertebral junction injuries
- Case 87 Odontoid fractures
- Case 88 Vertebral compression fractures
- Case 89 Sacral insufficiency fracture
- Case 90 Paget’s disease of the spine
- Case 91 Renal osteodystrophy
- Case 92 Calcific tendinitis of the longus colli
- Case 93 T2 hyperintense disc herniation
- Case 94 Disc herniation and cord compression
- Case 95 Postoperative disc herniation versus postsurgical scarring
- Case 96 Degenerative endplate alterations
- Case 97 Spinal dysraphism
- Case 98 Tethered spinal cord
- Case 99 Chiari I malformation
- Case 100 Spinal vascular malformations
- Case 101 Cord compression
- Case 102 Demyelinating/inflammatory spinal cord lesion
- Case 103 Subacute combined degeneration
- Case 104 Intradural cyst
- Case 105 Spinal CSF leaks
- Case 106 Leptomeningeal drop metastases
- Index
- References
Case 49 - Idiopathic intracranial hypertension
Published online by Cambridge University Press: 18 December 2013
- Frontmatter
- Dedication
- Contents
- Preface
- Case 1 Dense basilar artery sign
- Case 2 Global anoxic brain injury
- Case 3 Acute infarction
- Case 4 Vertebral artery dissection
- Case 5 Subacute infarct
- Case 6 Subarachnoid hemorrhage
- Case 7 Intracranial aneurysms
- Case 8 Giant aneurysms
- Case 9 Acute intracerebral hematoma
- Case 10 Cerebral amyloid angiopathy
- Case 11 Primary CNS vasculitis
- Case 12 Reversible cerebral vasoconstriction syndrome
- Case 13 Moyamoya disease/syndrome
- Case 14 Cortical venous thrombosis
- Case 15 Developmental venous anomalies
- Case 16 Dural arteriovenous fistula
- Case 17 Cavernous malformation
- Case 18 Tumefactive demyelinating lesion
- Case 19 Acute disseminated encephalomyelitis
- Case 20 Progressive multifocal leukoencephalopathy
- Case 21 Osmotic myelinolysis
- Case 22 Neurosarcoidosis
- Case 23 Posterior fossa masses in children
- Case 24 Low-grade glioma
- Case 25 Diffuse intrinsic pontine glioma
- Case 26 Pseudoprogression of GBM
- Case 27 Pseudoresponse in treatment of GBM
- Case 28 Low-grade oligodendroglioma
- Case 29 Primary CNS lymphoma
- Case 30 Pineal region tumors
- Case 31 Intraventricular masses
- Case 32 Colloid cyst
- Case 33 Primary intraosseous meningioma
- Case 34 Suprasellar meningioma
- Case 35 Pituitary macroadenoma
- Case 36 Brain abscess
- Case 37 Neurocysticercosis
- Case 38 Tuberculosis
- Case 39 Creutzfeldt–Jakob disease
- Case 40 Herpes encephalitis
- Case 41 Wernicke’s encephalopathy
- Case 42 Hypertrophic olivary degeneration
- Case 43 Adrenoleukodystrophy
- Case 44 Mild traumatic brain injury
- Case 45 Isodense subdural hematoma
- Case 46 Posterior reversible encephalopathy syndrome
- Case 47 Late-onset adult hydrocephalus secondary to aqueductal stenosis
- Case 48 Intracranial hypotension
- Case 49 Idiopathic intracranial hypertension
- Case 50 Rathke’s cleft cyst
- Case 51 FLAIR sulcal hyperintensity secondary to general anesthesia
- Case 52 Virchow–Robin spaces
- Case 53 Arachnoid granulations
- Case 54 Benign external hydrocephalus
- Case 55 Pitfalls in CTA
- Case 56 Asymmetric pneumatization of the anterior clinoid process
- Case 57 Fibrous dysplasia of skull base
- Case 58 Sphenoid bone pseudolesion
- Case 59 Clival lesions
- Case 60 Perineural spread
- Case 61 Cochlear dysplasia
- Case 62 Labyrinthitis ossificans
- Case 63 Superior semicircular canal dehiscence
- Case 64 Fluid entrapment in the petrous apex cells
- Case 65 Acquired cholesteatoma
- Case 66 Malignant otitis externa
- Case 67 Temporal bone fractures
- Case 68 Allergic fungal sinusitis
- Case 69 Invasive fungal sinusitis
- Case 70 Spontaneous CSF leaks and sphenoid cephaloceles
- Case 71 Juvenile nasal angiofibroma
- Case 72 Idiopathic orbital pseudotumor
- Case 73 Optic neuritis
- Case 74 Intraparotid lymph nodes
- Case 75 Benign mixed tumor
- Case 76 First branchial cleft cyst
- Case 77 Nasopharyngeal cysts
- Case 78 Cystic nodal metastasis
- Case 79 Low-flow vascular malformations
- Case 80 Parapharyngeal masses
- Case 81 Third branchial apparatus anomaly
- Case 82 Parathyroid adenoma
- Case 83 String sign
- Case 84 Carotid artery dissection
- Case 85 Traumatic arterial injury
- Case 86 Craniovertebral junction injuries
- Case 87 Odontoid fractures
- Case 88 Vertebral compression fractures
- Case 89 Sacral insufficiency fracture
- Case 90 Paget’s disease of the spine
- Case 91 Renal osteodystrophy
- Case 92 Calcific tendinitis of the longus colli
- Case 93 T2 hyperintense disc herniation
- Case 94 Disc herniation and cord compression
- Case 95 Postoperative disc herniation versus postsurgical scarring
- Case 96 Degenerative endplate alterations
- Case 97 Spinal dysraphism
- Case 98 Tethered spinal cord
- Case 99 Chiari I malformation
- Case 100 Spinal vascular malformations
- Case 101 Cord compression
- Case 102 Demyelinating/inflammatory spinal cord lesion
- Case 103 Subacute combined degeneration
- Case 104 Intradural cyst
- Case 105 Spinal CSF leaks
- Case 106 Leptomeningeal drop metastases
- Index
- References
Summary
Imaging description
The main role of imaging in this condition historically focused on exclusion of other pathological lesions that resulted in elevated intracranial pressure (ICP). CT was often used as a screening study to exclude a mass lesion prior to the lumbar puncture. The advent and widespread use of MRI disclosed abnormalities that indicate or suggest idiopathic intracranial hypertension (IIH) itself.
A number of imaging features have been described in IIH, and they uniformly pertain to sequelae of elevated intracranial pressure and/or CSF volume. The “empty sella” sign may result from a downward herniation of an arachnocele through the diaphragma sella. The pituitary gland may be compressed or flattened against the sellar floor. Elevated ICP may be transmitted to the optic nerve sheath (ONS), resulting in prominence of ONS, flattening of the posterior globe, or even intraocular protrusion of the optic nerve head (Fig. 49.1). Other signs include optic nerve tortuosity and optic nerve enhancement due to venous congestion.
There is an increasing realization that patients with suspected IIH must also be imaged with MR venography (MRV), in addition to routine MRI. MRV helps to rule out sinovenous thrombosis as a secondary cause of IIH and commonly demonstrates sinovenous stenoses in patients with IIH (Figs. 49.2, 49.3). Farb et al. identified venous stenoses in as many as 90% of patients with IIH, with a reported sensitivity and specificity of 93% using a contrast-enhanced elliptic centric-ordered imaging (1). It should be noted that standard time-of-flight (TOF) techniques are frequently associated with artifactual loss of signal in the transverse and sigmoid sinuses, and are unreliable in the detection of sinovenous stenosis. Optimal evaluation for underlying sinovenous stenosis includes either contrast-enhanced MRV or CT venography (CTV).
- Type
- Chapter
- Information
- Pearls and Pitfalls in Head and Neck and NeuroimagingVariants and Other Difficult Diagnoses, pp. 238 - 239Publisher: Cambridge University PressPrint publication year: 2013