Presentation on theme: "November 2010 Janica Walden, MD (Neuroradiology Fellow) and Thomas Bouldin, MD (Neuropathologist)"— Presentation transcript:
1 November 2010Janica Walden, MD (Neuroradiology Fellow) and Thomas Bouldin, MD (Neuropathologist)
2 Case # 1 Young adult male with PMH significant for NF-1 Had been followed over the past few years for a tectal glioma with secondary ventriculomegalyThe lesion and ventriculomegaly had been stable.The patient had been doing well until he died suddenly.
3 ImagingBrain MRI performed four months before death, when compared with prior MRIs, showedStable tectal mass, most compatible with a gliomaStable dilatation of the lateral and third ventriclesStable enhancing lesions within the left basal ganglia and right frontal lobe white matterStable abnormal T2 hyperintense signal in the cerebellar vermis.
5 Clinical CourseAlthough the patient had been doing well, he died suddenly.Postmortem MRI of the brain was performed in order to gain more insight as to the cause of death.
6 Postmortem Imaging-MRI The tectal glioma did not change in size or demonstrate any evidence of hemorrhage between the last premortem MRI and the postmortem MRI.There is development of lateral and third ventricular hydrocephalus between the two studies. The suggestion of trans-ependymal flow of CSF in the postmortem study may be an artifact.There is evidence of aqueductal obstruction .
7 Sagittal postmortem T1WI shows obstruction of cerebral aqueduct (arrow) by tumor.
8 Left panel: Section through formalin-fixed, postmortem specimen of midbrain and upper pons. A gray, gelatinous neoplasm is present in the midbrain in the region of the cerebral aqueduct. No cerebral aqueduct is identifiable in this section macroscopically.Right panel: The tectal glioma has histologic features of a pilocytic astrocytoma.
9 Usual Causes of Sudden Death Related to Intracranial Pathology Epilepsy (sudden unexplained death in epilepsy)Intracerebral hemorrhageSpontaneous subarachnoid hemorrhageSubdural hematomaEpidural hematomaBacterial MeningitisBrain tumorData from Black M, and Graham DI. Sudden unexplained death in adults caused by intracranial pathology. J Clin Pathol 55:44–50, 2002.
10 Tectal Glioma Expands tectum & obstructs aqueduct T2 hyperintense mass, may or may not enhanceTectal glioma: Most indolent, often only need CSF diversionOften associated with NF-1Focal areas of signal intensity in white matter & deep gray matter; typically involve globus pallidusMay involve brainstem80% 5-year progression free survivalProgression or dissemination is extremely rare.
11 Tectal Glioma: MRI High signal T2; minority isointense Expands tectum; obstructs aqueduct earlyRemains focal: Tectum/tegmental; (+/-) cerebral peduncles, thalamiFLAIR: High signalT1WI C+: Variable enhancementT2* GRE: Tectal: Hazy calcification, may extend up crura to thalami
12 Case #240 year-old male with 4-month history of blurry vision in his left eyeInitially evaluated by an ophthalmologist, with MRI of brain performed at an outside facilityMRI revealed extra-orbital mass behind the left eye.The patient was referred to a neurosurgeon.
13 ImagingMRI showed an extra-axial, dural-based mass along the left sphenoid wing, most consistent with a meningioma.The mass surrounded the ICA.There was enhancement along the left optic nerve, possibly reflecting extension of the mass or a dural reaction.
15 Clinical CourseGiven the patient’s deteriorating vision in his left eye, surgical resection was recommended in order to preserve vision. A left pterional craniotomy for decompression of the left optic nerve and for biopsy of the lesion were performed.Pathology was consistent with neurosarcoidosis.Post-operatively, patient had improved vision in left eye.Rheumatology was consulted for further treatment.
16 Photomicrograph of a histologic section from the biopsy of the intracranial mass shows granulomatous inflammation with several multinucleated giant cells (arrows). Special stains were negative for mycobacteria and fungi. The histologic changes are consistent with sarcoidosis.
17 Sarcoidosis Etiology remains unknown. CNS is involved in 5% (clinical) to 27% (autopsy) of cases.10-20 per 100,000 in North AmericaMost common symptom: CN deficit(s), most often facial nerve palsyOnset in 3rd-4th decadesGender: M:F = 2:1African-American: Caucasian-American = 10:1Often indolent disease, with up to 50% asymptomatic
18 NeurosarcoidosisMultisystem inflammatory disease characterized by noncaseating epithelioid-cell granulomasBest diagnostic clue: Solitary or multifocal CNS mass(es) plus an abnormal chest radiograph50% have periventricular T2 hyperintense lesionsInfiltrates perivascular (Virchow-Robin) spaces of brainMay cause a small vessel vasculitis
19 Neurosarcoidosis: MRI Wide spectrum of MRI enhancement patternsSlightly > 1/3 have multiple parenchymal lesionsSlightly > 1/3 have leptomeningeal involvement, nodular and/or diffuse10% solitary intra-axial mass5-10% hypothalamus, infundibular thickening5% solitary dural-based, extra-axial massOther: Vasculitis or ependymal enhancementDDx when dural based: meningioma
20 Neurosarcoidosis: MRI T2WI Lacunar infarcts (brainstem, basal ganglia)Hypointense material within subarachnoid space/sulci, focally or diffuseHypointense dural lesion(s)FLAIR ≈ 50% have periventricular T2 hyperintense lesionsHyperintense vasogenic edema 2° toInfiltration of perivascular (Virchow-Robin) spacesMay cause a small-vessel vasculitis.
21 Case #310 year-old child with intractable seizures who was previously healthy until recent onset of generalized tonic-clonic seizures and petit-mal seizuresManaged on anticonvulsants until 3 weeks prior to admission when child began to have worsening seizures and gait instabilityEEG showed persistent epileptiform activity, localized to the right hemisphere, with highest amplitude in temporal and parietal regions.
22 ImagingMRI showed:Atrophy and abnormal T2 signal within right hippocampus, suggesting right mesial temporal sclerosisAreas of abnormal increased T2/FLAIR signal are within the cortex and subcortical white matter of the posterior right parietal lobe, right frontal lobe, and right occipital lobe. Differential Dx includes post-ictal changes and encephalitis.
24 Histologic sections of cerebral cortex from brain biopsy. Left panel: In center of photomicrograph is a cluster of cells forming a “microglial nodule.”Right panel: Chronic inflammatory cells surround a blood vessel in the cerebral cortex. Microglial nodules and perivascular chronic inflammation are hallmarks of encephalitis.
25 Rasmussen Encephalitis Chronic, progressive, relentless, unilateral inflammation of brain of uncertain etiologyCharacterized by hemispheric volume loss and difficult to control focal seizure activity50% preceded by inflammatory episodeUsually begins in childhood (6-8 years of age)Refractory to antiepileptic medicationsUnilateral progressive cortical atrophy
26 Rasmussen Encephalitis: MRI T1WI: Blurring of cortical ribbon during early swelling; T2WI Early focal swelling of gyriGray, underlying white matter mildly hyperintense+/- Basal ganglia, hippocampi involvedLate: Atrophy of involved cerebral hemisphere or lobe.FLAIR: small areas of hyperintensity that progressively increase over timeLate: Atrophic, encephalomalacic/gliotic residual brain.MRS: ↓ N-acetyl-aspartate (NAA) and choline; ↑ myo-inositol, and ↑ glutamine/glutamate
27 Case # 460 year-old female with history of breast lymphoma diagnosed two years agoStatus post chemotherapy and radiation.Now presents with progressive weakness, unsteadiness, intermittent confusion, and right arm tremor.
28 Imaging FindingsEnhancing left parietal lesion, concerning for metastatic diseaseAbnormal signal in the left basal ganglia with expansion of the left caudate nucleus and lentiform nucleus; peripheral hyperintensity and central hypointensity on T2WI; no enhancementDifferential diagnosis includes lymphoma
30 Photomicrograph of histologic section from brain biopsy shows poorly differentiated neoplasm. Immunohistochemical stains confirmed that this is a diffuse large B-cell lymphoma. The primary breast lymphoma was also a diffuse large B-cell lymphoma.
31 Metastatic CNS Lymphoma Secondary spread of lymphoma to CNS is usually in the form of leptomeningeal infiltrates.Parenchymal lesions, when present, usually result from secondary involvement from the leptomeninges.Via infiltration of pervascular spacesPoor prognosisPeriventricular dissemination is rare.
32 Metastatic CNS Lymphoma: MRI T1WI: Single or multiple iso-or hypointense lesionsT2WI: Homogeneously iso-or hypointense to cortexFLAIR: nonsuppression of CSF in sulci with leptomeningeal involvementDiffusely enhances if dural mass; may see leptomeningeal enhancement
33 Case # 53 year-old child presented with a 3-week history of nausea and vomiting as well as headaches of increasing frequency and intensity.CT scan revealed an intraventricular mass within the 4th ventricle and associated ventriculomegaly.
34 ImagingMRI of the brain showed a 5.9 cm x 2.5 cm x 2.5 cm, partially cystic, enhancing mass expanding the 4th ventricle and extending inferiorly through the foramina of Magendie and Monroe.Adjacent mass effect on brainstem and cerebellumIncreased perfusion within the massGiven imaging characteristics, ependymoma was favored diagnosis.
37 Photomicrograph of a histologic section from the biopsy of the tumor shows a glioma with prominent perivascular pseudorosettes. Pseudorosettes are a characteristic histologic finding in ependymoma.
38 Ependymoma Slow-growing tumor of ependymal cells Third most common posterior fossa tumor in children (after pilocytic astrocytoma and medulloblastoma)20-30% of intramedullary spinal tumors in childrenDDx: Medulloblastoma and cerebellar pilocytic astrocytomaGross total resection plus radiation therapy correlates with improved survival.
39 Ependymoma: Imaging Findings Soft or "plastic" tumor squeezes out through 4th ventricle foramina into cisterns.2/3rd infratentorial, 4th ventricle1/3rd supratentorial, majority periventricular white matterCalcification is common (50%); +/- cysts, hemorrhage