CSF Rhinorrhea

CSF RHINORRHEA

• CSF Rhinorrhea is usually due to fracture of cribriform plate which is a part of Ethmoid.

CLASSIFICATION OF CSF RHINORRHEA

Traumatic and non-traumatic

Traumatic (>90%) –

• Approximately 80% of all traumatic leaks occur in the setting of accidental trauma, and the remaining traumatic leaks occur after neurosurgical and rhinological procedures.
• Le Fort II and Le Fort III Maxillary fracture and Nasoethmoid fracture.
• Nontraumatic (Nontraumatic etiologies include neoplasms and hydrocephalus

High pressure and low pressure flow

• High pressure flow- intracranial tumours & hydrocephalous
• Low pressure flow- congenital defects.

SITES OF CSF LEAK

• Most common site for leak is through cribrtform plate and ethmoidal air sinuses.
• Less common sites are through frontal and sphenoidal sinuses.
• Rarely, the leak can originate in the middle or posterior cranial fossa and can reach the nasal cavity by way of the middle ear and eustachian tube.

CLINICAL FEATURES

• Discharge is clear, watery, appears suddenly in a gush of drops when bending forward (tea pot sign) or straining
• Uncontrollable and cannot be sniffed back
• No associated sneezing, nasal congestion or lacrimation
• When collected in a test tube and allowed to stand, it remains clear (nasal discharge leaves a sediment)

DIAGNOSIS OF CSF RHINORRHEA

Basic clinical tests

• Rhinoscopy-visualisation of CSF leakage from paranasal sinuses
• Tissue test-unlike nasal mucous ,CSFdoes not cause a tissue to stiffen
• Filter paper test-sample of nasal discharge on a filter paper exhibits a light CSF border and a dark central area of blood ‘double ring sign’ or ‘ halo sign’ or ‘Target sign’ (in cases of traumatic CSF leak where blood and CSF are mixed.) –
• Queckenstedt test-compression of jugular veins leads to increased CSF leakage d/t increase in intracranial pressure.

Biochemical tests:

• Concentrations of glucose & protein are higher in CSF than in nasal discharge.
• Glucose content > 30mg/dI (nasal discharge – < 10 mg/dl)

Immunoelectrophoresis

• Beta-transferrin is the preferred biochemical marker of CSF. It helps in distinguishing CSF from other nasal secretions.
• Beta-trace protein is another chemical marker that could be used for the detection of CSF

CSF tracers:

• Intrathecal fluorescein dye administration, radionuclide cisternography, CT cisternography
• Localization of CSF leak
• Intrathecal injection of a dye or a radioisotope and placing pledges of cotton in the olfactory slit, middle meatus, Sphenoethmoidal recess and near the Eustachian tube and examine the pledges for radioactivity
• Olfactory slit – cribriform plate (most common site)
• Middle meatus – frontal or ethmoidal sinus
• Sphenoethmoidal recess – sphenoid sinus
• Eustachian tube – temporal bone

Radiological studies:

• High-resolution CT provides detailed information about the bony skull base anatomy, and MR1 assesses soft tissues , including unrecognized tumors and coincidental meningoencephaloceles

TREATMENT OF CSF RHINORRHEA

• Traumatic rhinorrhea often stops spontaneously
• Early cases of post-traumatic CSF rhinorrhea are managed conservatively consisting of 1-2 weeks trial of
  • Strict bed rest – Head elevation – Stool softeners
  • Advising patient to avoid coughing, sneezing, nose blowing, and straining
  • Prophylactic antibiotics to prevent meningitis.
  • Subarachnoid drainage through a lumbar catheter
• Persistent cases of CSF rhinorrhoea are treated surgically through nasal endoscopic or intracranial approach.
  • Nasal endoscopic approach is useful for leaks from the frontal sinus, cribriform plate, ethmoid or sphenoid sinuses.
  • Nasal intubation is contraindicated in CSF Rhinorrhea.