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Brain tumor imaginig 3 10th may 02

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Brain tumor imaginig 3 10th may 02

  1. 1. Brain Tumor Neuroimaging - 3 Dr Deb
  2. 2. I. Tumors of neuroepithelial tissue <ul><li>Astrocytic tumors </li></ul><ul><li>Oligodendroglial tumors </li></ul><ul><li>Ependymal tumors </li></ul><ul><li>Mixed gliomas </li></ul><ul><li>Choroid plexus papilloma </li></ul><ul><li>Neuroepithelial tumors of uncertain origin </li></ul><ul><li>Neuronal and mixed neuronal-glial tumors </li></ul><ul><li>Pineal tumors </li></ul><ul><li>Embryonal tumors </li></ul>
  3. 3. Oligodendroglial tumors <ul><li>Oligodendroglioma </li></ul><ul><li>Anaplastic (malignant) oligodendroglioma </li></ul>
  4. 5. Oligodendroglioma <ul><li>Most tumors show abnormalties of chromosome 19 and 1 </li></ul><ul><li>Oligodendrogliomas make up about 5% of intracranial tumors and 10% of gliomas. </li></ul><ul><li>They are relatively slow growing and often calcifed, except for the anaplastic variety which is rare </li></ul><ul><li>They occur in the hemispheres of the brain especially the frontal and temporal lobe and more commonly in the thalamus of children </li></ul><ul><li>Oligodendrogliomas act as mass lesions, infiltrating areas of brain. </li></ul><ul><li>If they infiltrate the motor area, there are seizures of a focal motor type or hemiparesis. </li></ul><ul><li>Infiltrating sensory regions may produce sensory symptoms or misinterpretations. </li></ul><ul><li>They also are associated with edema so can produce herniation. </li></ul>
  5. 6. <ul><li>Keith was 16 yrs old when he hit his head and had a seizure </li></ul><ul><li>Three weeks later he experienced another seizure. An MRI and CT scan performed at the time were negative. </li></ul><ul><li>He also complained of having several years of episodes of &quot;deja vu&quot; with nausea each time </li></ul><ul><li>Seven months later he experienced a blank staring episode followed by tonic clonic activity with left eye deviation. He was started on dilantin and another MRI was obtained which showed a right temoral lobe mass </li></ul>
  6. 7. Oligodendroglioma -
  7. 8. Neuronavigation / computer assisted surgery
  8. 9. <ul><li>3-dimensional rendering of a tumor located in the precentral gyrus. Functional data from magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) for the motor (MEF and MEA) and sensory (SEF, SEA) cortex clearly depict the laclisation of the central sulcus </li></ul>
  9. 10. <ul><li>The intraoperative visualization of these data using a navigation microscope allows to operate on tumors located in eloquent brain areas with lower morbidity.  </li></ul>
  10. 11. <ul><li>Leftsided oligodendroglioma, which could be removed without any speech deficits, because functional navigation clearly depicted the loacalization of the motor-speecha rea, which could beprserved during surgery (a / b). </li></ul>
  11. 12. <ul><li>Intraoperative imaging (d) showed some remaining tumor, which could be localized with an updated navigation (e) easily, so that the tumor could be removed completely (f). </li></ul>
  12. 13. <ul><li>Recurrent Right Parietal Oligodendroglioma. </li></ul><ul><li>a) Scalp surface showing previous craniotomy incision. </li></ul><ul><li>b) Software window function allowing inspection of the brain surface, tumor (green), superior sagittal sinus (blue) and cortical vessels (blue) defining primary motor and sensory cortex. </li></ul><ul><li>c) Intraoperative photograph of prepped and draped scalp with skin incision marked. </li></ul><ul><li>d) Same view after turning the craniotomy flap. The dura has been reflected inferiorly. The tumor, superior sagittal sinus, cortical vessels and primary motor and sensory cortex are visible. </li></ul><ul><li>e) Magnified view of the computer models from the same orientation. </li></ul><ul><li>f) Same view with the brain model removed to reveal the extent of the underlying tumor mass. </li></ul>
  13. 14. Case <ul><li>This 38 year old right handed male presented at age 35 with a generalized seizure. </li></ul><ul><li>A CT scan performed at a community hospital showed a focal, high left parietal mass lesion. </li></ul><ul><li>A subsequent stereotactic biopsy showed the lesion to be an oligodendroglioma. </li></ul><ul><li>The patient has been followed with annual neuroimaging and clinical exams, and has been stable with rare focal seizures. </li></ul><ul><li>A recent increase in seizure frequency prompted consideration of surgical resection of the mass. </li></ul><ul><li>A 3D reconstruction was performed to aid in the overall surgical plan. </li></ul>
  14. 15. A. shows the 3D outline of the skin and face in a dot rendering. The tumor (green), ventricular system (blue), major venous drainage (red) and a segment of brain around the tumor (gray) are shown B. shows the models with the brain segment removed. C. shows the tumor at the brain surface impinging on primary motor cortex. D. the brain segment removed to allow an understanding of the volume of tumor underlying normal brain.
  15. 16. B. Oligodendroglioma - Gross <ul><li>a oligodendroglioma replacing part of the basal ganglia. Like any glial tumor an oligodendroglioma subtly infiltrates surrounding tissue but is much more slow-growing than a glioblastoma. </li></ul>
  16. 17. Oligodendroglioma - Micro <ul><li>The tumor is made up of uniform oval cells with clear to pale pink cytoplasm and relatively uniform oval to round nuclei that have a fried egg or &quot;box like&quot; appearance. </li></ul><ul><li>The stroma is made up of capillaries having a chickenwire appearance between groups of tumor cells </li></ul><ul><li>There is no good grading system and no specific immunoperoxidase stain to identify them. </li></ul>
  17. 18. Oligodendroglioma - High <ul><li>A high power photomicrograph of an oligodendroglioma, demonstrating the uniform nuclei and &quot;box like&quot; or &quot;fried egg&quot; appearing cells. </li></ul><ul><li>The cytoplasm is clear and the cytoplasmic membranes are well defined. </li></ul><ul><li>The nuclei are round and relatively regular. </li></ul>
  18. 19. I. Tumors of neuroepithelial tissue <ul><li>Astrocytic tumors </li></ul><ul><li>Oligodendroglial tumors </li></ul><ul><li>Ependymal tumors </li></ul><ul><li>Mixed gliomas </li></ul><ul><li>Choroid plexus papilloma </li></ul><ul><li>Neuroepithelial tumors of uncertain origin </li></ul><ul><li>Neuronal and mixed neuronal-glial tumors </li></ul><ul><li>Pineal tumors </li></ul><ul><li>Embryonal tumors </li></ul>
  19. 20. C. Ependymal tumors <ul><li>Ependymoma Variants: </li></ul><ul><ul><li>cellular papillary, </li></ul></ul><ul><ul><li>epithelial, </li></ul></ul><ul><ul><li>clear cell, </li></ul></ul><ul><ul><li>mixed </li></ul></ul><ul><li>Anaplastic (malignant) ependymoma </li></ul><ul><li>Myxopapillary ependymoma </li></ul><ul><li>Subependymoma </li></ul>
  20. 22. Ependymoma <ul><li>Primary brain tumors are second common to lymphoma in children </li></ul><ul><li>Post fossa tumors are common above age 2 </li></ul><ul><li>Supratentorial tumors below two years </li></ul><ul><li>Ependymomas are third most common tumor in children. 15 % of post fossa malignancies </li></ul><ul><li>They classically arise from ependymal cells lining the fourth ventricle </li></ul><ul><li>Commonly, the tumor expands the fourth ventricle and extends through the foramen of Magendie and through the foramina of Luschka </li></ul><ul><li>The tumors are often calcified and may demonstrate a large cystic component </li></ul><ul><li>Inhomogeneous enhancement is usually seen </li></ul><ul><li>seeding throughout the subarachnoid space can be seen. </li></ul>
  21. 23. Ependymoma - Clinical <ul><li>Nausea, vomiting, headache as well as ataxia </li></ul><ul><li>The over-all five year survival rate is approximately 50%. </li></ul><ul><li>Supratentorial ependymomas, however, are usually more aggressive and have a poorer prognosis </li></ul><ul><li>As stated above, ependyomomas are the third most common posterior fossa tumor in childhood behind juvenile pilocytic astrocytomas and medulloblastomas </li></ul>
  22. 24. Ependymoma <ul><li>3-year-old presents with headache and ataxia </li></ul><ul><li>A right cerebellar and fourth ventricle mass which is somewhat higher in attenuation than the remaining brain parenchyma. </li></ul><ul><li>In addition, there is marked dilatation of the temporal horns indicating hydrocephalus. </li></ul>
  23. 25. Ependymoma – MR T1, contrast
  24. 26. Ependymoma – MR Sagital <ul><li>An approximately 4 cm fourth ventricular mass with probable extension toward the outlets of the fourth ventricle </li></ul>
  25. 27. Ependymoma - Sagital <ul><li>This saggital section of the posterior fossa shows an ependymoma filling much of the fourth ventricle. Ependymomas are more common in children and arise in or near the ventricles because they arise from ependymal cells </li></ul>
  26. 28. Ependymoma - Cellular
  27. 29. Ependymoma – Papillary
  28. 30. Ependymoma – Clear cell
  29. 31. C. Ependymal tumors <ul><li>Ependymoma Variants: </li></ul><ul><ul><li>cellular papillary, </li></ul></ul><ul><ul><li>epithelial, </li></ul></ul><ul><ul><li>clear cell, </li></ul></ul><ul><ul><li>mixed </li></ul></ul><ul><li>Anaplastic (malignant) ependymoma </li></ul><ul><li>Myxopapillary ependymoma </li></ul><ul><li>Subependymoma </li></ul>
  30. 32. Anaplastic Ependymoma
  31. 33. Anaplastic Ependymoma
  32. 34. C. Ependymal tumors <ul><li>Ependymoma Variants: </li></ul><ul><ul><li>cellular papillary, </li></ul></ul><ul><ul><li>epithelial, </li></ul></ul><ul><ul><li>clear cell, </li></ul></ul><ul><ul><li>mixed </li></ul></ul><ul><li>Anaplastic (malignant) ependymoma </li></ul><ul><li>Myxopapillary ependymoma (Cauda) </li></ul><ul><li>Subependymoma </li></ul>
  33. 35. C. Ependymal tumors <ul><li>Ependymoma Variants: </li></ul><ul><ul><li>cellular papillary, </li></ul></ul><ul><ul><li>epithelial, </li></ul></ul><ul><ul><li>clear cell, </li></ul></ul><ul><ul><li>mixed </li></ul></ul><ul><li>Anaplastic (malignant) ependymoma </li></ul><ul><li>Myxopapillary ependymoma </li></ul><ul><li>Subependymoma </li></ul>
  34. 36. History <ul><li>A 34 year old right handed man </li></ul><ul><li>Episodes of nausea and gastric discomfort. X 6 month </li></ul><ul><ul><li>These episodes would last for several minutes and were preceded by feelings of deja vu or an unpleasant burning smell. </li></ul></ul><ul><ul><li>After MRI scan and anticonvulsant medications started </li></ul></ul><ul><ul><li>More recently, his wife reports that he has demonstrated periods of agitation and irrationality. </li></ul></ul><ul><ul><li>follow-up medical attention and an MRI scan was performed. </li></ul></ul><ul><li>Physical Examination </li></ul><ul><ul><li>The patient demonstrated a mild speech hesitancy with naming. He was otherwise neurologically normal. </li></ul></ul>
  35. 38. <ul><li>The anterior choroidal artery is elevated (shown by the arrow). This confirms that the tumor is located in the inferior portion of the temporal lobe; it probably arose from the floor of the temporal horn to grow within the ventricle. </li></ul>
  36. 40. <ul><li>Tumor composed of small cells with a regular nucleus, forming small chains and islands disseminated throughout an abundant fibrillary framework, spongy in certain areas. The vessels may be of large caliber and their wall is sometimes very fibrous. Several calcifications are visible. A subependymoma is grossly visible in a brain section (IV.01.g1) that also contains a glioblastoma. </li></ul>
  37. 41. I. Tumors of neuroepithelial tissue <ul><li>Astrocytic tumors </li></ul><ul><li>Oligodendroglial tumors </li></ul><ul><li>Ependymal tumors </li></ul><ul><li>Mixed gliomas </li></ul><ul><li>Choroid plexus papilloma </li></ul><ul><li>Neuroepithelial tumors of uncertain origin </li></ul><ul><li>Neuronal and mixed neuronal-glial tumors </li></ul><ul><li>Pineal tumors </li></ul><ul><li>Embryonal tumors </li></ul>
  38. 42. Mixed gliomas <ul><ul><ul><li>Mixed oligo-astrocytoma </li></ul></ul></ul><ul><ul><ul><li>Anaplastic (malignant) oligo-astrocytoma </li></ul></ul></ul>
  39. 43. T1 Post-gadolinium T1 T1 Post-gadolinium T1 Proton density T2 <ul><li>This is a case of a 37 year old man with a history of seizures started 2 years ago </li></ul><ul><li>The MRI showed a signal intensity in the right frontopaietal area of the brain and a cystic lesion located in the motorstrip </li></ul>
  40. 44. The 3D reconstruction was performed from SPGR MR images and phase contrast MR angiogram
  41. 45. Intraoperative findings
  42. 46. Mixed Oligoastocytoma
  43. 47. I. Tumors of neuroepithelial tissue <ul><li>Astrocytic tumors </li></ul><ul><li>Oligodendroglial tumors </li></ul><ul><li>Ependymal tumors </li></ul><ul><li>Mixed gliomas </li></ul><ul><li>Choroid plexus papilloma </li></ul><ul><li>Neuroepithelial tumors of uncertain origin </li></ul><ul><li>Neuronal and mixed neuronal-glial tumors </li></ul><ul><li>Pineal tumors </li></ul><ul><li>Embryonal tumors </li></ul>
  44. 48. Choroid plexus papilloma <ul><ul><ul><li>Choroid plexus papilloma </li></ul></ul></ul><ul><ul><ul><li>Choroid plexus carcinoma </li></ul></ul></ul>
  45. 49. Choroid plexus tumor <ul><li>Choroid Plexus Papilloma (WHO Grade I) </li></ul><ul><li>- Choroid Plexus Carcinoma (WHO Grade III-IV) </li></ul><ul><li>Cell of Origin: Choroid plexus epithelium </li></ul><ul><li>Common Locations: </li></ul><ul><li>Adults - Fourth ventricle </li></ul><ul><li>Children - Lateral ventricle </li></ul><ul><li>Demographics: Children > Adults. 40-50% papillomas seen in first year of life, 85% < 5 yrs. Carcinomas usually seen only in pediatric age group. </li></ul><ul><li>Clinical Presentation: Hydrocephalus </li></ul><ul><li>Histology: Papillomas have characteristic lobulated gross appearance. Most are well-differentiated and may resemble normal choroid plexus, however, anaplastic transformation may occur. Parenchymal invasion suggests carcinoma, but can be seen with benign . </li></ul><ul><li>Special Stains : Cytokeratin distinguishes from ependymoma; Prealbumin (transthyretin) may be helpful (although metastases may also stain positive) </li></ul><ul><li>Progression: CSF seeding may occur in both papillomas and carcinomas. </li></ul><ul><li>Radiology: Well-demarcated intraventricular (or cerebellopontine angle) mass with hydrocephalus. Calcification especially frequent in fourth ventricular tumors. In adult patients the fourth ventricle is more common. The tumor is attached to the choroid plexus. </li></ul><ul><li>Comments: Hydrocephalus may reflect multiple factors, including CSF over-production, ventricular obstruction, and impaired CSF reabsorption. Can present as a congenital neoplasm. </li></ul>
  46. 50. Choroid plexus papilloma   Sagittal Gd Enhanced T1W MR Axial Gd Enhanced T1W MR
  47. 51. This 9 month old child presented with a history of lethargy Contrast
  48. 52. Choroid plexus papilloma
  49. 53. I. Tumors of neuroepithelial tissue <ul><li>Astrocytic tumors </li></ul><ul><li>Oligodendroglial tumors </li></ul><ul><li>Ependymal tumors </li></ul><ul><li>Mixed gliomas </li></ul><ul><li>Choroid plexus papilloma </li></ul><ul><li>Neuroepithelial tumors of uncertain origin </li></ul><ul><li>Neuronal and mixed neuronal-glial tumors </li></ul><ul><li>Pineal tumors </li></ul><ul><li>Embryonal tumors </li></ul>
  50. 54. Neuroepithelial tumors of uncertain origin <ul><ul><ul><li>Astroblastoma </li></ul></ul></ul><ul><ul><ul><li>Polar spongioblastoma </li></ul></ul></ul><ul><ul><ul><li>Gliomatosis cerebri </li></ul></ul></ul>
  51. 55. Immunohistochemistry <ul><ul><ul><li>Astroblastoma </li></ul></ul></ul>
  52. 56. Gliomatosis Cerebri
  53. 57. Gliomatosis Cerebri : Axial gadolinium-enhanced T2-weighted and T1
  54. 58. Gliomatosis Cerebri
  55. 59. I. Tumors of neuroepithelial tissue <ul><li>Astrocytic tumors </li></ul><ul><li>Oligodendroglial tumors </li></ul><ul><li>Ependymal tumors </li></ul><ul><li>Mixed gliomas </li></ul><ul><li>Choroid plexus papilloma </li></ul><ul><li>Neuroepithelial tumors of uncertain origin </li></ul><ul><li>Neuronal and mixed neuronal-glial tumors </li></ul><ul><li>Pineal tumors </li></ul><ul><li>Embryonal tumors </li></ul>
  56. 60. Neuronal and mixed neuronal-glial tumors <ul><li>Gangliocytoma </li></ul><ul><li>Dysplastic gangliocytoma of the cerebellum (Lhermitte-Duclos) </li></ul><ul><li>Desmoplastic infantile ganglioglioma </li></ul><ul><li>Dysembryoplastic neuroepithelial tumor </li></ul><ul><li>Ganglioglioma </li></ul><ul><li>Anaplastic (malignant) ganglioglioma </li></ul>
  57. 61. A 68-year-old woman presented with a third nerve palsy.
  58. 62. Gangliocytoma
  59. 63. Gangliocytoma
  60. 64. Neuronal and mixed neuronal-glial tumors <ul><li>Gangliocytoma </li></ul><ul><li>Dysplastic gangliocytoma of the cerebellum (Lhermitte-Duclos ) </li></ul><ul><li>Desmoplastic infantile ganglioglioma </li></ul><ul><li>Dysembryoplastic neuroepithelial tumor </li></ul><ul><li>Ganglioglioma </li></ul><ul><li>Anaplastic (malignant) ganglioglioma </li></ul>
  61. 65. LHERMITTE-DUCLOS DISEASE (DYSPLASTIC GANGLIOCYTOMA) <ul><li>WHO Grade I </li></ul><ul><li>Cell of Origin: Cerebellar neurons (hamartomatous?) </li></ul><ul><li>Synonyms: Ganglioneuroma, Purkinjioma, Granular cell hypertrophy of the cerebellum, Gangliocytoma dysplasticum, Hamartoma of the cerebellum </li></ul><ul><li>Common Locations: Cerebellar hemispheres </li></ul><ul><li>Demographics: Early adulthood </li></ul><ul><li>Clinical Presentation: Hydrocephalus; may also be found as an incidental lesion </li></ul><ul><li>Histology: Derangement of normal laminar cellular organization of cerebellum: 1) Thickening of outer molecular cell layer, 2) Loss of middle Purkinje cell layer, 3) Infiltration of inner granular cell layer with dysplastic ganglion cells </li></ul><ul><li>Special Stains: Synaptophysin positive </li></ul><ul><li>Progression: Good prognosis with surgical excision. Recurrence rare. </li></ul><ul><li>Radiology: Non-enhancing cerebellar hemisphere mass with characteristic striated MR appearance. Occasionally contains calcifications. </li></ul><ul><li>Comments: Association with Cowden's disease (mucosal neuromas and breast cancer) </li></ul>
  62. 66. Neuronal and mixed neuronal-glial tumors <ul><li>Gangliocytoma </li></ul><ul><li>Dysplastic gangliocytoma of the cerebellum (Lhermitte-Duclos) </li></ul><ul><li>Desmoplastic infantile ganglioglioma </li></ul><ul><li>Dysembryoplastic neuroepithelial tumor </li></ul><ul><li>Ganglioglioma </li></ul><ul><li>Anaplastic (malignant) ganglioglioma </li></ul>
  63. 67. DESMOPLASTIC INFANTILE GANGLIOGLIOMA <ul><li>WHO Grade I </li></ul><ul><li>Cell of Origin: Large, mature neurons + glial component </li></ul><ul><li>Synonyms: Together with superficial cerebral astrocytoma may be referred to as desmoplastic supratentorial neuroepithelial tumors of infancy </li></ul><ul><li>Common Locations: Large, hemispheric superficial tumors </li></ul><ul><li>Demographics: Early infancy </li></ul><ul><li>Clinical Presentation: Macrocephaly </li></ul><ul><li>Histology: Glial and neuronal differentiation. Moderate pleomorphism; infrequent mitoses. Abundant desmoplasia characteristic. </li></ul><ul><li>Special Stains: Neuronal component confirmed by synaptophysin or electron microscopy. GFAP positive. </li></ul><ul><li>Progression: Good prognosis with surgical excision. </li></ul><ul><li>Radiology: Very large mass with cystic and solid components. The solid portion, which tends to be superficial, enhances intensely. </li></ul><ul><li>Comments: Related to superficial cerebral astrocytoma, which is distinguished only by its lack of neuronal elements. </li></ul>
  64. 68. Neuronal and mixed neuronal-glial tumors <ul><li>Gangliocytoma </li></ul><ul><li>Dysplastic gangliocytoma of the cerebellum (Lhermitte-Duclos) </li></ul><ul><li>Desmoplastic infantile ganglioglioma </li></ul><ul><li>Dysembryoplastic neuroepithelial tumor </li></ul><ul><li>Ganglioglioma </li></ul><ul><li>Anaplastic (malignant) ganglioglioma </li></ul>
  65. 69. Four-year-old boy with partial complex seizures
  66. 71. Neuronal and mixed neuronal-glial tumors <ul><li>Gangliocytoma </li></ul><ul><li>Dysplastic gangliocytoma of the cerebellum (Lhermitte-Duclos) </li></ul><ul><li>Desmoplastic infantile ganglioglioma </li></ul><ul><li>Dysembryoplastic neuroepithelial tumor </li></ul><ul><li>Ganglioglioma </li></ul><ul><li>Anaplastic (malignant) ganglioglioma </li></ul>
  67. 72. Ganglioglioma <ul><li>GANGLIOCYTOMA/GANGLIOGLIOMA </li></ul><ul><li>WHO Grade I </li></ul><ul><li>Cell of Origin: Large, mature neurons +/- glial component </li></ul><ul><li>Common Locations: May occur anywhere in neural axis, but especially common in temporal lobe. </li></ul><ul><li>Demographics: May occur in any age; most common first 2 decades. </li></ul><ul><li>Clinical Presentation: Seizures </li></ul><ul><li>Histology: Gangliocytomas composed only of neuronal element. Gangliogliomas also have glial component in addition. Varied histologic appearance poorly correlated with prognosis. </li></ul><ul><li>Special Stains: Synaptophysin, neuron-specific enolase may verify neuronal component. Gangliogliomas will also show GFAP positivity. </li></ul><ul><li>Progression: Slow-growing lesion. Low malignant potential restricted to glial component of ganglioglioma. </li></ul><ul><li>Radiology: Well-defined solid or mixed cystic/solid mass with minimal or no mass effect. Calcification common. Enhancement pattern variable, often peripheral. </li></ul><ul><li>Comments: Rare association with congenital malformations such as Down's syndrome, callosal dysgenesis, and neuronal migration disorders. </li></ul>
  68. 73. Ganglioglioma
  69. 75. Neuronal and mixed neuronal-glial tumors <ul><li>Gangliocytoma </li></ul><ul><li>Dysplastic gangliocytoma of the cerebellum (Lhermitte-Duclos) </li></ul><ul><li>Desmoplastic infantile ganglioglioma </li></ul><ul><li>Dysembryoplastic neuroepithelial tumor </li></ul><ul><li>Ganglioglioma </li></ul><ul><li>Anaplastic (malignant) ganglioglioma </li></ul>
  70. 76. <ul><li>Billy was 8 yrs old when in the spring of 1998 his parents noticed that he would occasionally vomit in the mornings, he seemed to lack energy, and he would fall aspleep at odd times-at his desk in school, or on the bench during his little league game. </li></ul><ul><li>In August, Billy was brought to the ophthalmologist for a routine eye exam before school started for the year. </li></ul>
  71. 77. I. Tumors of neuroepithelial tissue <ul><li>Astrocytic tumors </li></ul><ul><li>Oligodendroglial tumors </li></ul><ul><li>Ependymal tumors </li></ul><ul><li>Mixed gliomas </li></ul><ul><li>Choroid plexus papilloma </li></ul><ul><li>Neuroepithelial tumors of uncertain origin </li></ul><ul><li>Neuronal and mixed neuronal-glial tumors </li></ul><ul><li>Pineal tumors </li></ul><ul><li>Embryonal tumors </li></ul>
  72. 78. Pineal tumors <ul><ul><li>Pineocytoma </li></ul></ul><ul><ul><li>Pineoblastoma </li></ul></ul><ul><ul><li>Mixed pineocytoma/pineoblastoma </li></ul></ul>
  73. 79. Pineocytoma.
  74. 80. Pineocytoma. This tumour contains larger cells resembling pineocytes.
  75. 81. Pineal tumors <ul><ul><li>Pineocytoma </li></ul></ul><ul><ul><li>Pineoblastoma </li></ul></ul><ul><ul><li>Mixed pineocytoma/pineoblastoma </li></ul></ul>
  76. 82. Pineoblastoma <ul><li>Female, 28 years, complaining of headache and partial visual defect. </li></ul><ul><li>MR images : Elongated, hyperintense (T1), isointense (T2), irregular, enhancing pineal lesion, resulting in hydrocephalus which was relieved by ventriculostomy. </li></ul><ul><li>The final diagnosis after stereotaxy is a pineoblastoma </li></ul>
  77. 83. Pineoblastoma. <ul><li>The cells have hyperchromatic nuclei surrounded by small amounts of cytoplasm </li></ul>
  78. 84. I. Tumors of neuroepithelial tissue <ul><li>Astrocytic tumors </li></ul><ul><li>Oligodendroglial tumors </li></ul><ul><li>Ependymal tumors </li></ul><ul><li>Mixed gliomas </li></ul><ul><li>Choroid plexus papilloma </li></ul><ul><li>Neuroepithelial tumors of uncertain origin </li></ul><ul><li>Neuronal and mixed neuronal-glial tumors </li></ul><ul><li>Pineal tumors </li></ul><ul><li>Embryonal tumors </li></ul>
  79. 85. Embryonal tumors <ul><li>Medulloepithelioma </li></ul><ul><li>Neuroblastoma Variant: ganglioneuroblastoma </li></ul><ul><li>Ependymoblastoma </li></ul><ul><li>Retinoblastoma </li></ul><ul><li>Primitive neuroectodermal tumors (PNET) with multipotential differentiation - neuronal, astrocytic, ependymal, muscle, melanocytic, etc. </li></ul><ul><ul><li>a. Medulloblastoma Variants: desmoplastic, medullomyoblastoma, melanocytic medulloblastoma </li></ul></ul><ul><ul><li>b. Cerebral (supratentorial) and spinal PNETs </li></ul></ul>
  80. 86. Medulloepithelioma
  81. 87. Embryonal tumors <ul><li>Medulloepithelioma </li></ul><ul><li>Neuroblastoma Variant: ganglioneuroblastoma </li></ul><ul><li>Ependymoblastoma </li></ul><ul><li>Retinoblastoma </li></ul><ul><li>Primitive neuroectodermal tumors (PNET) with multipotential differentiation - neuronal, astrocytic, ependymal, muscle, melanocytic, etc. </li></ul><ul><ul><li>a. Medulloblastoma Variants: desmoplastic, medullomyoblastoma, melanocytic medulloblastoma </li></ul></ul><ul><ul><li>b. Cerebral (supratentorial) and spinal PNETs </li></ul></ul>
  82. 88. Medulloblastoma - Gross <ul><li>Note the large gray mass occupying much of the vermis of the cerebellum. This is a medulloblastoma which is a tumor of children, is very fast growing and very malignant. Fortunately, the tumor is also radiosensitive </li></ul>
  83. 89. Recurrence of a medulloblastoma. Image fusion (c) of a sagittally oriented contrast enhanced T1-weighted MR image (a) with an F-18 DG SPECT image (b) . (d) Image fusion after chemotherapy.
  84. 90. Medulloblastoma - Microscopy <ul><li>Cells composed mainly of dark staining nuclei with fairly marked pleomorphism. </li></ul><ul><li>The tumor is partly differentiating into more mature astrocytic type cells as evidenced by the positive brown immunostaining for Glial Fibrillary Acid Protein. (GFAP). </li></ul><ul><li>These tumors can also differentiate along neuronal lines; however, their differentiation does not render them less malignant. </li></ul>

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