its cell bodies lie in
the retina
(ganglion cells)
their axons form the
optic nerve, optic
chiasma & optic tract.
their axons form the
optic nerve, optic
chiasma & optic tract.
2nd order neuron
its cell bodies lie in the L.G.B
their axons form the optic
radiation that terminate in the
visual cortex of the occipital
lobe of the brain
Types of speech
Apraxia of speech
and involves inconsistent production of speech sounds and rearranging of sounds in a word
Cluttering
a rapid rate of speech, which makes speech difficult to understand.
Dysarthria
is a weakness or paralysis of speech muscles
Dysprosody
It is characterized by alterations in intensity, in the timing of utterance segments, and in rhythm,
cadence, and intonation of words.
Muteness
is complete inability to speak
Speech Sound Disorders
involve difficulty in producing specific speech sounds
Stuttering
Voice disorders
are impairments, often physical, that involve the function of the larynx or vocal resonance
Clinical
presentation
Risk Factors of Brain Tumors
Age\Gender\Home & Work Exposures\Family
History\Exposure to infections, viruses and
allergens\Electromagnetic fields \Race and
ethnicity\Ionizing Radiation\Head Injury & Seizures
Types of brain tumors
Adults tumors
primary
tumors are
usually
supratentorial.
glioblastoma multiforme
Malignant, high-grade tumor of astrocytes
Most common primary malignant CNS tumor in adults
Usually arises in the cerebral hemisphere;
characteristically crosses the corpus callosum
Butterfly lesion
Histology
Characterized by regions of necrosis surrounded by tumor
cells (pseudopalisading) and endothelial cell proliferation;
tumor cells are GFAP positive.
Poor prognosis
schwannoma
Benign tumor of Schwann cells
involves cranial or spinal nerves; within the cranium, most
frequently involves cranial nerve VIII at the cerebellopontine
angle (presents as loss of hearing and tinnitus)
Tumor cells are S-100 positive.
Histology
prognosis
Good prognosis after resection
meningioma
Benign tumor of arachnoid cells
Most common benign CNS tumor in adults
More commonly
seen in women; rare
in children
May present as seizures; tumor compresses, but does not invade, the cortex.
Imaging reveals a round mass attached to the dura.
Histology
shows a whorled pattern; psammoma bodies may
be present.
Prognosis
Good prognosis
Grade 1
93%
Grade 2
5%
Grade 3
2%
Children tumors
primary tumors are
usually infra tentorial
pilocytic astrocytoma
Benign tumor
of astrocytes
Most common CNS tumor in
children; usually arises in the
cerebellum
Imaging reveals a
cystic lesion with a
mural nodule
Histology
Biopsy shows Rosenthal fibers (thick
eosinophilic processes of astrocytes)
and eosinophilic granular bodies;
tumor cells are GFAP positive.
Grading
ependymoma
Malignant tumor of
ependymal cells
Most commonly arises in
the 4th ventricle; may
present with
hydrocephalus
Histology
Perivascular pseudorosettes are a
characteristic finding on biopsy
Prognosis
Recur after
surgery,
acquire more
aggressiveness
Prognosis depends
on the location
and its histologic
grade.
medulloblastoma
Malignant tumor derived
from the granular cells of the
cerebellum (neuroectoderm)
Histology
Histology reveals small, round
blue cells; Homer-Wright
rosettes may be present.
Poor prognosis; tumor
grows rapidly and spreads
via CSF.
Metastasis to the cauda equina is
termed 'drop metastasis
Prognosis
Resection & radiation
allow 5-year survival
of 75%.
Metastatic
Brain
tumors
Breast\Lung\Skin\Kidney\GIT
Other tumors
OLIGODENDROGLIOMA
Malignant tumor of oligodendrocytes
Imaging reveals a calcified tumor in the
white matter, usually involving the frontal
lobe; may present with seizures
Histology
'Fried-egg' appearance of cells on biopsy
prognosis
Slow-growing, long survival (5-10 yrs)
Grade 2 (with treatment): 10-20 years
Grade 3 (with treatment): 5-10 years
5-year survival rate is 75%,
10-year survival rate is 50%.
Investigations of space
occupying lesions of the brain
Eye Examination
Risks of Brain Surgery
Allergic reaction to anesthesia\Bleeding in the brain\A blood clot\Brain swelling\Coma\Impaired
speech, vision, coordination, or balance\Infection in the brain or at the wound site\Memory
problems\Seizures\Stroke