Determination of site of leak in CSF rhinorrhoea

There are different ways by which the location of leak can be determined in cases of CSF rhinorrhoea.

• Injection of dye (flourescein / radioisotope) into intrathecal space and placing cotton pledgets in different parts of nasal cavity. Depending on which pledget gets soaked in the dye, site of leak can be determined
  • Olfactory cleft – cribriform plate
  • Sphenoethmoidal recess – Sphenoid sinus
  • Middle meatus – frontal / ethmoid sinus
  • Inferior meatus posteriorly near eustachian tube – Temporal bone – reaches via eustachian tube
• High resolutaion CT scan – head –  coronal cuts – bone window
• CT cisternogram – taken after injection of radioopaque dye into intrathecal space via cisterna magna
• MRI cisternogram – T2 weighted – does not require injection of dye and is hence non invasive