2. CSF leak are the results of osseous defects at the
skull base coupled with dura and arachnoid injury
due to pressure gradient system .
3. Physiology
CSF forms a jacket of fluid round the brain and spinal cord acting as a
buffer against sudden jerks.
Secreted by choroid plexus in the lateral,third & fourth ventricle &
absorbed into dural venous sinuses by arachnoid villi.
Villi have one-way valve mechanism allowing CSF of the subarachnoid
space to be absorbed in to the blood .
Total volume of CSF varies 90 to 150 ml.
4. Csf - Physiology
It is secreted at the rate of about 20ml/hr (350-500mL/day).
Thus total CSF is replaced three to five times every day.
CSF pressure rise on coughing, sneezing, nose blowing straining on
stools or lifting heavy weight.
These activities should be avoided in cases of CSF leak or after its repair.
9. Sites of Leakage
1. CSF from Anterior cranial fossa reaches
the nose via
a) Cribriform plate
b) Roof of ethmoid
c) Frontal sinus
2. CSF from Middle cranial fossa
1. injuries to sphenoid sinus
2. In fracture of temporal bone
CSF Middle Ear Eustachian Tube nose (CSF otorhinorhea)
10. Etiology – CSF Rhinorrhoea
Trauma (commonest)
Accidental
Surgical ( Trans-sphenoidal hypophysectomy,skull base surgery)
Neoplasms (benign/malignant) invading skull base
Inflammations (mucocele of sinuses ,sinunasal polyposis, fungal infections of sinuses & osteomyelitis
erode the bone & dura)
Congenital (meningocele,meningoencephalocele & gliomas with skull base defect)
Idiopathic
12. Clinically
H/o clear watery discharge on bending head/ straining ,sudden gush can’t
be sniffed back
Headache
nausea
Signs of facial injury
Anosmia
Vertigo
Meningism
Seizures
Fever
13. Clinical testing
Reservoir sign :When rising in morning CSF collected in sinuses on
bending head
Double target sign when collected on a piece of filter paper with central
blood & peripheral lighter halo
Handkerchief test
Valsalva manuover
14.
15. Double target sign when collected on a piece of filter paper with central
blood & peripheral lighter halo – also “halo sign”
16. Handkerchief Test
Discharge from the nose is
blown into a handkerchief
and is allowed to dry. If the
discharge is CSF the
handherchief will not
stiffen, if the discharge is
secretions from the nose
the handkerchief stiffens
due to the presence of
mucin in the nasal
secretions.
18. Biochemical
B2 transferrin
Sensitive & specific
Only few drops of CSF is needed
Perilymph & aqueous also contains it but not in nasal discharge
Beta trace protein
Specific for CSF
Glucose testing
> 30 mg/dl in CSF
<10 mg/dl in nasal discharge
24. Localization contd.
Coronal CT cisternogram
showing CSF draining from
the subarachnoid space
through the roof of the right
ethmoid sinus(arrow) into the
nose.
27. Localization contd.
Intrathecal fluorescein study
it can be done preoperative invasive procedure
0.25-0.5 Ml of 5% fluorescein diluted with 10mL of CSF
is injected.
patient lies in 10 degree head down position.
Dye can be detected intranasally with the help of
endoscope
Dye appears bright yellow but when seen with blue
filter it appear fluorescent green.
Helps localize the lesion
The most sensitivve test to detect
CSF leak is intrathecal
radionucleotide test.
30. Management
Early case of post traumatic Case of CSF rhinorrhea can be managed by :
Conservative measures
Bed rest
Elevating the head of bed
Stool softeners
Avoidance of nose blowing, sneezing & straining
Prophylactic antibiotics can be used to prevent meningitis
Acetazolamide ↓ formation of CSF
Mannitol as per ICP
31. Surgical treatment – history of
Galen in 2nd century AD mentioned about csf
Miller in 1826 described csf circulation
Dandy pioneered intracranial repairs in 1926.
Extracranial repair by dohlam in 1948
Waiganand described endoscopic repair in 1981
32.
33. Indication for Surgery
Recurrent attacks of meningitis with continuing leak despite
conservative management
†Patients with enlarging pneumocephalus ( > 2 cc persistent intracranial
air - significant) despite conservative treatment †
Acute traumatic or post-operative leaks that recur or persist after 10-13
days of conservative management including Lumbar CSF drainage
Proven intermittent or delayed leaks †
High pressure leaks with hydrocephalus