Nervous system

The CNS is isolated
Surrounded by bones so created
Providing protection
From trauma infection
The common things for which we're slated.

Isolation is still more emphatic
As brain and cord have no lymphatic
And barrier's maintained
Between blood and the brain
All of value and not artifatic.

Infection once inside the skull
Is like water within leaking hull
It serves no good purpose
But covers the surface
Meninges are thickened and dull.

Lesions in brain which compress
Place structures afar under stress
So edema cerebral
Can make brain stem feeble
A bloody necrotic soft mess.

Tumors cerebral and spinal
Are often quite fatal and final
They don't look the same
As those outside the brain
Except for some growths of the pineal.

Meningiomas rise inside the head
Benign remain local don't spread
lf they press on the brain
Patient may seem insane
Symptoms depend where they tread.

Glioblastomas we fear
Like a plague that is coming too near
Palisades and necrosis
Tripolar mitosis
Survival of less than a year.

Schwannomas grow on the eighth nerve
Having cells with a fusiform curve
In patterns to see
Like Antoni type B
Neurosurgeons know what they deserve.

They call some brain tumors benign
Through the microscope that may be fine
But they grow in a shell
That confines as they swell
So it's only a question of time.