7.1a. Contrast axial T1 Wtd MRI

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7.1a. Contrast axial T1 Wtd MRI
7.1b. Contrast coronal T1 Wtd MRI
7.1c. Contrast sagittal T1 Wtd MRI
Figure 7.1 An enhancing ring lesion within the
left posterior frontal lobe
Diagnosis
Pyogenic Abscess Differential diagnosis
Metastasis  While abscess can be differentiated
from metastasis by MR imaging, appropriate
patients clinical history and clinical findings
are needed to aid in accurate diagnosis.
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7.2a,b,c. Pre-Contrast axial T1 Wtd MRI
7.2d,e,f. Post-Contrast axial T1 Wtd MRI
Figure 7.2 Multiple enhancing ring lesions in a
immunocompromised patient
Diagnosis
Fungal Abscesses Differential diagnosis
Multiple Metastasis  While abscess can be
differentiated from metastasis by MR imaging,
appropriate patients clinical history and
clinical findings are needed to aid in accurate
diagnosis.
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Fig 7.3a. T2-weighted images of the brain at just
above the level of roof of the lateral ventricles
of a young homosexual man.
Findings
Diagnosis
Areas of T2-weighted hyperintensity within the
deep paraventricular white matter (arrows).
Human Immunodeficiency Virus (HIV) Encephalopathy
A myelin-stained section of the brain specimen
reveals severe diffuse myelin pallor ().
Horizontal section of the brain revealing
abnormal left frontal lobe white matter from
demyelinization (arrow).
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Fig. 7.3b. T2-weighted image of the brain at the
level of frontal horns of a young homosexual man
Findings
Diagnosis
Foci of T2-weighted hyperintensity involving the
peripheral white matter at or close to
cortico-medullary junction (arrows) and left
basal ganglia (arrow head).
Progressive Multifocal Leukoencephalopathy
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Fig 7.3c. Post-contrast axial CT image of the
brain at the level of frontal horns/basal ganglia
of a young homosexual man.
Findings
Diagnosis
Enhancing ring lesion (arrow) within the left
caudate nucleus.
Primary CNS Lymphoma
Coronal brain section reveals a tumor involving
the left caudate nucleus (arrows).
Photomicrographic show perivascular collections
of lymphoma cells
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Fig 7.3d. Post-contrast axial CT image of the
brain at the level of the basal ganglia of a drug
addict
Findings
Diagnosis
Enhancing ring lesion (arrow) within the right
caudate nucleus.
CNS Toxoplasmosis
Horizontal section of the right hemisphere
reveals an irregular necrotic lesion in the right
caudate nucleus
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Fig. 7.3e. T1-weighted image of the brain at the
level of frontal horns of a young homosexual man
7.3e. Pre-Contrast Axial T1 Wtd MRI
Diagnosis
Findings
Focal area of T1 Wtd low signal intensity,
capping the right frontal horn.
Cytomegalo Virus Infection.
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Fig 7.3f. Axial T2 Wtd image of the Brain.
Diagnosis
Findings
Cryptococcal Meningitis
Multiple small areas of increased T2 Wtd signal
within both basal ganglia (arrows).
Coronal brain section reveals multiple
soap-bubble like lesions in the basal ganglia
(arrows).
Photo micrograph reveals encapsulated
Cryptococcus neoformans with budding forms
(arrow).