Cns Tumors And Infections Part3

INTRA-AXIAL 1. Supratentorial 2. Infratentorial I.

Low grade astrocytoma

Types of Gliomas  Astrocytoma o astrocytes  Oligodendrogliomas o oligodendrocytes  Ependymomas o ependymal cells  Choroid plexus pappilomas/carcinomas Astrocytoma Subtypes 1. Low grade astrocytoma 2. Anaplastic astrocytoma 3. Glioblastoma multiforme Astrocytoma -

-

25 – 30% of adult cerebral hemispheric gliomas 30% of gliomas in children in adults, the peak age of incidence is 20-50 years old the histopathologic classification of glial tumors is based on the prevalent cell type present and the grading of the tumor by the most malignant portion present On MR: o Relatively homogeneous masses without much peritumoral edema o The margins of the lesion are often clearly defined on MR o Low grade astrocytomas not infrequently involve both the white matter and adjacent cortex  This appearance may stimulate an infarct. If the lesion does not conform to a vascular territory or there is marked enhancement, tumor should be suspected  Occasionally, a follow-up scan is necessary in order to differentiate a tumor from an infarct o contrast enhancement is variable in astrocytomas o generally, higher grade tumors demonstrate more marked enhancement than lower grade tumors, but there are many exceptions o low grade astrocytomas often show no or minimal enhancement; no edema o calcification is not uncommon in low grade astrocytomas (seen in approximately 20% of cases on CT) o CT detects calcification much better than MR

Post contrast T1-weighted axial shows no enhancement Bilateral Thalamic Glioma (Astrocytoma)

Obstruction of 3rd ventricle; hydrocephalus II.

Anaplastic necrosis, vascular proliferation, and cyst formation common significant edema and inhomogenicity MR Characteristics considerable inhomogenicity hypointensity on T1 hyperintensity on T2 surrounding edema most show gadolinium enhancement

A 22-year old male with headache

45-year old male complaining headache

There is a large amount of vasogenic edema in superior fronto-parietaloccipital hemisphere. After contrast administration, there is an irregular ringlike structures. The abnormal signal involves both white matter and cortex, but does not conform to an expected vascular distribution suggesting tumor rather than infarct.

III.

GBM a highly malignant type of astrocytoma the most common and most malignant glioma

-

account for 15-20% of primary CNS neoplasms in adults, and are rare in children Glioblastoma multiforme occurs most commonly between ages 40-60 and is rare in childhood. Glioblastoma most commonly arises in the frontal and temporal lobes, but may occur in any region of the brain and can spread rapidly. It commonly crosses the corpus callosum to involve both cerebral hemispheres. Glioblastoma may also spread through the ventricles and subarachnoid space.

S/Sx -

elevated intracranial pressure are usually present (headache, nausea, vomiting, papilledema, visual disturbances) headache and seizure are the most common presentation focal deficits may result from local invasion of the tumor intracranial hemorrhage may result in acute onset of symptoms

-

arteriovenous malformations other astrocytomas abscess CNS lymphoma cavernous malformation oligodendroglioma metastasis

DDx

53-year old male with superior quadrant visual loss and dizziness

Subependymal Giant Cell Astrocytoma common locations: lateral ventricle attached to caudate head associations: most patients have tuberous sclerosis, of those with TS, 6-16% will develop this tumor demographics: children, young adults (first two decades) histology: large cells that variously resemble astrocytes, although may express neuronal markers - radiology: usually seen with other features of tuberous sclerosis (cortical tubers, calcified subependymal tubules, white matter streaks). May obstruct foramen of Monroe and cause hydrocephalus. Enhancement and calcification are both common.

Glioblastoma Multiforme (GBM) Oligodendroglioma Bakit wala nito? Sige, pagtyagaan ang notes: 90% with calcification relatively avascular ring enhancement INFRATENTORIAL • cerebellar astrocytoma • medulloblastoma • ependymoma • • • • • • •

Juvenile Pilocytic Astrocytoma the most common astrocytomas in children occur most often in patients younger than 25 years old astrocytoma is the most common and most malignant glioma astrocytomas are responsible for 50 % of primary pediatric CNS tumors accounts for 80-85% of cerebellar astrocytomas and 60% of optic gliomas JPAs usually present in older-aged children as opposed to medulloblastomas most frequently arises in the cerebellar hemispheres, along the optic tracts, and around the third ventricle, but may also be found in the cerebral hemispheres or anywhere else astrocytes are present

• •

usually well-demarcated lesions associated with cyst formation usually indolent lesions and rarely transform to a highgrade malignancy

Signs and Symptoms • related to obstructive hydrocephalus and mass effect including nausea, vomiting, visual disturbances, headache, irritability, ataxia Differential Diagnosis • other astrocytomas, brain metastases, ependymoma, oligodendroglioma, medulloblastoma, high-grade glioma Case •

•

7 ½ y/o with nausea, vomiting, and headache

•

complications include hydrocephalus, secondary to compression of the CSF pathways, and leptomeningeal dissemination, with subsequent weakness from spinal cord compression

Imaging • the diagnostic test of choice is MRI with and without gandolium • t1-weighted images typically demonstrate a hypointense lesion while • t2-weighted images reveal a hyperintense mass with surrounding edema • the tumor contrast enhances homogeneously on gandolium administration • leptomeningeal dissemination occurs in up to 40% of patients and so pre-surgical spinal MRI should also be obtained

Precontrast solid and cystic portions of centrally positioned cerebellar mass. Postcontrast showed a solid portion enhancing

Case •

• • • • • • • •

Medulloblastoma primarily a pediatric tumor with a peak age of incidence of 3-5 years 15% of childhood brain tumors Only 0.4-1% of adult brain tumors the tumor most commonly arises in the posterior fossa of the brain between the brainstem and the cerebellum although supratentorial origins have been reported in children, the most common site affected is the cerebellar vermis while in adults the lateral hemispheres of the cerebellum are most often involved patient presentation can be attributed to increased intracranial pressure (ICP) and cerebellar dysfunction increased ICP causes headache, nausea and vomiting, and cranial nerve VI palsy cerebellar symptoms are due to midline infiltration causing progressive truncal ataxia

•

12 y/o presenting with 2-mo history of headache

Hypointense posterior fossa mass in the region of cerebellar vermis extending exophytically into 4th ventricle. The 3rd ventricle and aqueduct show dilatation secondary to obstructive hydrocephalus. MR post-gandolium mass shows heterogeneous enhancement

•

5 y/o male

Differential Diagnosis • ependymoma • pilocytic astrocytoma Ependymoma accounts for 2-6% of intracranial mass

•

•

common locations: 4th ventricle for children and cerebral hemispheres for adults CT: lesion appear heterogeneous on imaging, exhibit heterogeneous enhancement, and are usually well defined with lobulated margins

•

• • • •

Brainstem Gliomas make up almost 10% of intracranial tumors in children three distinct anatomic locations pontine, tectal, and cervicomedullary age: average is 7 years of age; ¾ being > 20 years old

Signs and Symptoms • tectal: macrocrania, headaches • focal tegemental mesencephalic: hemiparesis • diffuse intrinsic pontine glioma: ataxia, headache, bulbar signs, nausea and vomiting, multiple cranial nerve palsies CT findings • gliomas appear as hypoattenuating masses at CT with variable enhancement depending on the glioma Case •

•

• • •

12 y/o male with flu-like symptoms

Cerebellar Hemangioblastoma accounts for 2% of all intracranial tumors occurs during the 3rd-4th decade of life 60% appear as cystic masses with a peripheral enhancing nodule most common locations: cerebellar hemispheres, vermis, medulla

CNS Infections Sorry, blurred. Hindi kaya ng katawang tao ko ang pagdecipher. I didn’t include the pictures – kamusta naman para siyang MRI ng unstable patient. Yeba!

CNS Infections common in children usually in newborns Congenital CMV most common of TORCH infections transplacental transmission in up to 50% of maternal infections with 5-10% of fetuses symptomatic neonatal symptoms include hepatosplenomegaly, jaundice, psychomotor retardation, chorioretinitis, and deafness. Mental retardation and deafness in 20%. - Intracranial involvement depends on time of infection and can include migrational anomalies, cerebellar hypoplasia, and intracranial calcifications (periventricular). Leading cause of brain disease and deafness in children 90% of infected neonates demonstrate asymptomatic or subclinical involvement. Herpes encephalitis HSV 2 accounts for 80-90% of neonatal and almost all congenital infections Herpes encephalitis most common cause of sporadic viral encephalitis - predilection for temporal lobes In adults, HSV 1 accounts for 95% of all fatal cases of sporadic encephalitis and usually results from reactivation of the latent virus MRI is preferred for imaging and follow-up studies of herpes encephalitis T2 weighted MRI hyperintensity corresponding to edematous changes in the temporal lobes, inferior frontal lobes, and insula with a predilection for medial temporal lobes foci of hemorrhage occasionally can be observed on MRI spares basal ganglia in the adult form, a predilection for the limbic system – temporal lobe, cingulated gyrus, or subfrontal region is characteristic on MR examination, early findings of edema as evidenced by decreased signal on T1 weighted imaging and increased signal on T2 weighted imaging may be found the edema often extends into the insular cortex with sparing of the putamen Neurocystercosis caused by tapeworm Taenia solium involving CNS, muscles, heart tissue Acute Vs Chronic Phase (hindi na kaya ng powers ko basahin kasi super blurred, pinasadahan lang ni doc ‘to kaya eto lang din ang notes ko…) Acute Chronic Focal seizures Calcifications Bacterial Meningitis CT findings of bacterial meningitis are commonly nonspecific and even normal in the majority of cases In severe cases, noncontrast evaluation may show abnormal ill-defined filling of the subarachnoid spaces with isoattenuating material which may show diffuse enhancement after contrast Brain Abscess Common primary sources of infection include sinusitis, otitis, and dental abscesses. CT: a ring-enhancing mass lesion with a hypodense center, often surrounded by a substantial amount of edema Toxoplasmosis 10% of AIDS patients, up to 40% of CNS infections in AIDS up to 70% seropositivity in general population clinical: HA (di ko alam bakit HA), fever, lethargy, focal neurologic deficit necrotizing encephalitis with this walled abscess formation

3-4 cm lesions, small lesions solid enhancement larger ringenhancing locations: BG, WM, CM jen (what the?!) major ddx in AIDS = lymphoma o helpful distinguishing factors: no spread across corpus callosum, larger number of small lesions, response to antibiotic Subdural empyema essentially collections of pus located between the dura and leptomeninges they are most commonly the result of direct extension secondary to sinus infection (frontal most common), but may also result from meningitis with organisms entering the subdural space through dural sinus or bridging veins. And since I was inspired… The wrong news, on the wrong page On June 5, 2008, newspapers in Manila carried the front-page headline: “Obama makes history.” First of all, the headline was not specific and it was wrong. It should have read: “Obama makes US history.” He and US Sen. Hillary Clinton did not make history in the Philippines or in the world. There have been and there still are many black and women presidents in the world. The Philippines already has had two women presidents. The Americans should be exposed for being white supremacists, hypocrites and male chauvinists. That historical event in the United States did not deserve front-page space in Philippine news. We Filipinos should stop thinking that we are Americans because we are not. Americans are actually laughing at us for being copycats and parasites—both behaviors feed on the American superego and superiority complex. The Americans will be devastated if Filipinos become like the Iranians. Even their neighbors, the Mexicans, could not care less about them; the Mexicans don’t want to talk to them. Their excuse: just like the French’s, “no speak English,” and they are succeeding. Half of California and the Western states are now Spanish-speaking. It is Montezuma’s revenge. The Mexicans would never do what Filipino officials did for an American rapist. The media should stop glamorizing US Ambassador Kristie Kenney. She is not our fairy godmother. She actually helped fund the Jemaah Islamiyah and Abu Sayyaf with the super generous rewards (from P50 million to P500 million) to informers of terrorists. Of course, the booty is shared with the Abu Sayyaf. This is happening right under the noses of Philippine military and government officials. As every Filipino knows, these terrorist groups have been menacing our country, not the United States. American political and humanitarian activities in Southern Mindanao and Sulu are actually making the peace process with the Muslims more difficult. The Americans are dividing our country just like what they did in Vietnam and what they’re doing now in Iraq. The obvious reason: so that Filipinos will continue to be dependent politically, economically and militarily on the United States. It serves America’s geopolitical interests in Asia. The Americans have been raping the sovereignty of our nation by direct interference in our country’s internal affairs and Filipinos seem to be enjoying this. There are many examples: The US intelligence agencies control the access to the websites of Philippine government agencies like the Department of Health and even the Philippine Senate; this I discovered recently. These blatant, illegal intrusions are just the tip of the iceberg. If Senator Obama wins the presidency of the United States, I suggest putting that news in the middle of the classified ads. BERNARDO D. MORANTTE JR., M.D., 23 Mt. Fairweather St., Filinvest 1, Quezon City

Camera Men:

Lisa, Eisa, Romy

Camera by: Transcribers: Notes by:

Pril Pril, Shia, Romy, and Geli Geli