CSF rhinorrhea

CSF rhinorrhea

• Leakage of CSF in to the nose

• Clear /

• mixed with blood (in a/c head injuries)

Etiology

• Trauma (commonest)• Accidental• Surgical ( FESS, nasal polypectomy, trans sphenoidal hypophysectomy,skull

base surgery)

• Neoplasms (benign/malignant) invading skull base

• Inflammations (mucocele of sinuses ,sinu nasal polyposis, fungal infections of sinusitis & osteomyelitis erode the bone & dura)

• Congenital (meningocele,meningoencephalocele & glioma with skull base defect)

• Idiopathic

Site of leakage

1. anterior cranial fossa a) Cribriform plate

b) Roof of ethmoid

c) Frontal sinus

2. Middle cranial fossa 1. injuries to sphenoid sinus

2. In # of temporal bone CSF ME ET nose (CSF otorhinorhea)

Diagnosis

• h/o clear watery discharge on bending head/ straining

• sudden gush can’t be sniffed back

• Reservoir sign : • When rising in morning csf collected in sinuses on bending head

• After a head trauma • Double target sign when collected on a piece of filter paper with central

blood & peripheral llighter halo

• Nasal endoscopy localize site of CSF leak

• Otoscopic /microscopic examination of ear } CSF otorrhinorhea

Laboratory tests

• 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

Localisation of site

• High resolution CT scan• Coronal & axial cuts at 1-2 mm } bony defects

• Axial } frontal & sphenoid sinus

• MRI• T2 weighted image Site of leak

• Active CSF leak is needed

• Non invasive

Treatment

• Conservative

• Bed rest

• Elevating the head

• Stool softeners

• Avoidance of node blowing, sneezing & straining

• Prophylatic abx } meningitis

• Acetazolamide } ↓ formn of CSF

Surgical repair

• Neurosurgical intra cranial approach

• Extra dural approach• External ethmoidectomy } cribriform plate

• Trans septal sphenoidal approach } sphenoid

• Osteoplastic flap } frontal

• Trans nasal endoscopic approach• With endoscope

• Site of leak 1. Cribriform plate2. Lateral lamina close to anterior ethmoid a3. Roof of ethmoid4. Frontal sinus leak5. Sphenoid sinus

• Preparation of graft site• Underlay placement of graft extra durally (mucosa for small defect….. Septal cartilage

if>2cm)• Surgical & gelfoam strengthen • Lumbar drain if CSF pressure is high• abx

• Intrathecal fluorescein study • Pre operatively }to dx site • Intra operatively for repair• Invasive• 0.25-0.5 ml of 5% fluorescein mixed with patients own CSF is injected & pt lies in 10 ’

head down position for some time dye ca be detected intranasally with the help of endoscope……….appears bright yellow but when seen with blue filter } flurescentgreen

• Localise the lesion

• CT cisternogram• Localise the lesion • Intrathecal injection of iohexol & CT • Where B2 transferrin can’t be done