CSF RHINORRHOEA

Dr. Parth RajdevMMIMSR Mullana (Ambala)

CSF BASICS Cerebrospinal fluid (CSF) is a clear,

colorless body fluid found in the brain and spine. It is produced in the choroid plexuses of the ventricles of the brain.

•It acts as a cushion or buffer for the brain's cortex, providing basic mechanical and immunological protection to the brain inside the skull.

CSF BASICS : CIRCULATIONProduced by Choroid plexus in lateral

ventricle and fourth ventricles

Through foramen of Monro

third ventricle Through aqueduct of Sylvius

fourth ventricle Through foramina of

Luschka Subarachnoid space over brain and spinal

cord

Reabsorbed into venous sinus blood via arachnoid granulations

CSF BASICS Total volume of CSF varies from 90 to

150 m.l. It is secreted at the rate of about 20ml/h

(300-350 ml/day) Therefore total CSF is replaced 3-5

times a day. Normal CSF pressure at lumbar

puncture is 50-150 mm H2O It rises on coughing, sneezing, nose

blowing, straining on stools or lifting heavy weight.

CSF RHINORRHOEA

•Leakage of CSF into nose.

•It may be clear fluid or mixed with blood.

Aetiology Trauma : Most common cause. It can be

either accidental or surgical.

SURGICAL TRAUMA includes:- Endoscopic sinus surgery. Trans-sphenoidal hypophysectomy Nasal polypectomy. Skull base surgery.

INFLAMMATIONS : Mucoceles of sinuses. Sinunasal polyposis. Erode bone and Fungal infections of sinuses. dura. Osteomyelitis.

NEOPLASMS: Both benign and malignant, invading the skull base.

CONGENITAL LESIONS: Meningocoele Meningoencephalocoele Gliomas.

IDIOPATHIC CAUSES

•SITES OF LEAKAGE

Anterior crainial fossa:i. Cribriform plate.ii. Root of ethmoidal cells.iii. Frontal sinus

Middle cranial fossa :Injuries to sphenoid sinus

Fracture Temporal bone:• CSF reaches middle ear and then escapes

through the eustachian tube into the nose (CSF otorinorrhoea)

DIAGNOSIS•History of clear watery discharge from

nose on bending the head or straining.•It may be seen on rising in the morning

when the patient bends his head (reservoir sign – fluid which had collected in the sinuses, particularly sphenoid, empties into the nose)

•It should be differentiated from nasal discharge of allergic or vasomotor rhinitis.

•Nasal discharge, stiffens the handkerchief because of its mucus content.

•Double target sign : CSF rhinorrhoea after head trauma is mixed with blood shows this sign when collected on a piece of filter paper i.e. central red spot and peripheral lighter halo.

DIAGNOSTIC NASAL ENDOSCOPY

Nasal endoscopy can help to localize CSF leak in some cases.

LABORATORY TESTSoBeta-2 transferrin : a protein seen in CSF

and not in nasal dischrge, it’s presence is specific and sensitive test.• Requires only a few drops of CSF.• Perilymph and aqueous are the only other

fluids which contain this protein.

oBeta trace protein : also specific for CSF , secreted my meninges and choroid plexus.

LOCALIZATION OF SITE1. HIGH RESOLUTION CT SCAN: Coronal

and axial cuts to see bony defects.

2. CT Cisternogram :It requires intrathecal injection of iohexol

and CT scan to localize site of leakage.

3. MRI : T2 weighted image in depicting site of leak. It requires that CSF leak is active at the time of scan.

• Indicated also if encephalocele or intracranial pathology is suspected.

4. INTRATHECAL FLUORESCEIN STUDYIt is an invasive procedure, use of

intrathecal radioactive substances has been abandoned.

0.25-0.5ml of 5% fl. Dye injected. Patient lies in 10◦ head down position for sometime.

Dye appears green when seen with a blue filter.

TREATMENTEarly cases of post-traumatic CSF leak

can be managed by conservative measures such as bed rest, elevation of the head of the bed, stool softners, and avoidance of nose blowing, sneezing and straining.

Prophylactic antibiotics can be used to prevent meningitis.

These measures can be combined with lumbar drainage.

Surgical Repair

A. Neurosurgical intracranial approach.

B. Extradural approaches : • External ethhmoidectomy for cribriform

plate and ethmoid area.• Trans-septal approach for sphenoid.• Osteoplastic flap approach for frontal

sinus leak.

C. Transnasal endoscopic approach : Most of the leaks from anterior cranial fossa

and sphenoid sinus can be managed endoscopically

Principles of repair:• Defining the site of leak.• Preparation of graft site.• Underlay grafting of fascia extradurally

followed by placement of mucosa.• If bony defect>2cm, it is repaired with

cartilage.• Placement of surgical and gelfoam further

strengthens area.

TYPES OF GRAFTS It depends on the size and location of the

defect, If the defect is large it can be fixed with

bone or cartilage graft taken usually from nasal turbinates.

If the defect is small, it can be repaired with fascia lata grafts, temporalis fascia.

Fibrin glue, surgicel, gelfoam is used to stabilize the graft

•High antibiotic smeared nasal packing.•Sometimes fat from thigh or abdomen is used

to plug the defect in place of fascia graft.

•Lumbar puncture if CSF pressure is high.•Antibiotics•(prophylacticaly)