neuro procedures (Told) Flashcards
CSF PRESSURE
LESS THAN 25-30 CM (250-300mm) Water(Spinal Fluid)
spinal fluid is comparable to
blood without RBCor WBC
DOING A SPINAL TAP
CT SCAN SHOULD PRECEED SPINAL TAP UNLESS MENINGITIS IS SUSPECTED.
Needle- SHORT BEVEL
ONLY
L4-L5 is first choice
causes of LOW PRESSURE
spinal fluid
BELOW 7 cm. (70mm)H2O
( Spinal Fluid)
Hypo-production
Distal to Occlusion
Spinal fluid leak
Spinal cord tumor
causes of high spinal fluid pressure
ABOVE 25-30 cm.
(250-300mm)H2O
(Spinal Fluid)
Hyper-production
Proximal to Occlusion
Malabsorption of spinal
fluid
Obesity. Pseudo tumor
cerebri
New bleeding from a
cerebral bleed will give
CSF the appearance of
Cherry Limeade
XANTHOCHROMIC
spinal fluid means
Old blood pigments
Remote bleeding
normal appearance of spinal fluid
CLEAR
Usually normal
1-3 monocytes &
lymphocytes
CLOUDY spinal fluid
If greater
than 200 WBC/cc or
400 RBC/cc
Infection/Inflammation
cell findings in spinal fluid
neutrophils- baccterial infection
lymphocytes viral infections (mumps,/ fungal/ TB)
Monocytes (macrophages)- chronic conditions (purple u shape)
gram stain
60-90% positive in bacterial infections
fungal stain looks like
big purple blobs, pink stretchiness in between
glucose, proteins in CSF
GLUCOSE- CSF GLUCOSE LAGS ONE HOUR BEHIND BLOOD GLUCOSE NEVER
LOWER THAN 80% OF BLOOD GLUCOSE
PROTEIN- LESS THAN 45 MG/DL (1 MG/DL RISE FOR EVERY 1000 RBC PRESENT.)
special tests- oligoclonal bands = MS
EPIDURAL SPACE
POTENTIAL SPACE THAT CONTAINS NO FLUID OR BLOOD ONLY ACCESS
TO THE NERVE ROOTS & DISC MATERIAL
WHAT IS AN EPIDURAL ?
SPACE OUTSIDE THE SPINAL
CANAL ACCESSABLE TO NERVE
ROOTS. MEDICATIONS CAN REMAIN
OUTSIDE THE SPINAL CANAL.
CATHETERS ARE INSERTED INTO
EPIDURAL SPACE TO INFUSE
ANASTHETICS OR NARCOTICS
EEG BRAIN MAPPING
DIGITAL SIGNALS CAN BE CONVERTED TO COLOR &
3D IMAGES IF DESIRED.
HELPS LOCATE FOCUSES OF FUNCTION OR DYSFUNCTION
RADIOGRAPHIC IMAGING
PLAIN X-RAY IS USED LESS OFTEN FOR
NEUROLOGIC DIAGNOSIS EXCEPT AS A
SCREEN FOR FRACTURES.
lateral x-ray should show
at least 7 vertebrae
ALL
7 CERVICAL VERTEBRAE
PLUS T-1
CT scans- more cameras
mean more heat and radiation!!
FASTER AND MORE DETAIL COMES WITH RISKS!!
EQUAL TO MORE THAN ONE
HUNDRED CHEST X-RAYS
When is CT valuable?
abcess, tumor (needs IV contrast)
kidney stones
spinal fractures
hemorrhages
MEDICINE’ HOT SUGAR
Nuclear glucose (FDG)
Positron Emission Tomogram Scan
“cancer just can’t resist having a PET”
HOW MEDICINE’S HOT SUGAR WORKS
FDG injected into patient
METOBOLISM OF FDG IN THE GLUCOSE PATHWAY GIVES OFF POSITRON + GAMMA RADIATION
CANCER CELLS USE MORE GLUCOSE THAN NORMAL CELLS
AND EMIT MORE
GAMMA RADIATION
Glioblastomas and lymphomas and stuff show up as black dots
T-1 and T-2 images
PROTONS WOBBLE
BUT THEY DON’T FALL DOWN
T-1 RELAXATION
LONGITUDINAL TO
THE MAGNETIC FIELD
T-2 RELAXATION
TRANSVERSE
TO THE MAGNETIC
FIELD
IN T-2 WEIGHTED IMAGES CSF (WATER) IS
BRIGHT. In FLAIR is T-2 with spinal fluid brightness blocked out
IN T-1 WEIGHTED IMAGES CSF (WATER) IS
DARK
How stuff looks on T-1
DARK:
•CSF
- Increased Water – edema, tumor, infarct, inflammation, infection, hemorrhage (hyper acute or chronic)
- Low proton density, calcification
- Flow Void
BRIGHT: Fat Subacute hemorrhage Melanin Protein-rich Fluid Slowly flowing blood Gadolinium Laminar necrosis of an infarct
How stuff looks on T-2
Dark:
•Low Proton Density, calcification, fibrous tissue
- Paramagnetic substances - deoxyhemoglobin, methemoglobin (intracellular), iron, hemosiderin, melanin
- Protein-rich fluid
- Flow Void
Bright:
•Increased Water – edema, tumor, infarct, inflammation, infection, subdural collection
•Methemoglobin (extracellular) in subacute hemorrhage
FLUID-ATTENUATED INVERSION RECOVERY
FLAIR
EDEMA AND GLIOSIS
ARE HYPERINTENSE
Using the MRI effectively
SCLEROTIC LESIONS
IN BRAIN TISSUE (M.S.)
tumor
when there is edema or excess fluid (meningitis)
angiography
soft tissue surrounded y bone
Not as good as CT for acute stroke
CLINICAL PEARLS
SPINAL TAP BEST FOR MENINGITIS, DEGENERATIVE NEUROLOGIC CONDITIONS AND DISEASES SUSPECTED TO ALTER SPINAL FLUID PRESSURE OR CIRCULATION.
ALWAYS DO CT SCAN BEFORE SPINAL TAP UNLESS INFECTION (MENINGITIS WITH NEURO SIGNS) IS SUSPECTED.
different imaging for different stuff
MRI IS BEST FOR MOST TUMORS, EVALUATING SOFT TISSUES INSIDE BONEY CAVITIES (DISK DISEASE), AND VASCULAR LESIONS.
PET SCANS LOOK FOR CANCER.
CT SCAN IS BEST FOR ACUTE CEREBRAL BLEEDING, ABCESSES AND ALL FRACTURES
young girl, papilledema, normal CT scan, high pressure spinal tap, no bacteria or WBC in CSF. Dx?
PSEUDOTUMOR CEREBRI
old lady falling down
CSF- high protein, no white cells
dx?
ALBUMINOCYTOLOGIC DISSOCIATION
OR
GUILLAIN-BARRE SYNDROME
Give Iv IG
