CSF rhinorrhoea is diagnosed by
(B) Beta 2 transferrin # investigations:> CSF as compare to nasal secretion has a central area of blood with outer ring or halo (Halo sign)> Glucose testing: CSF glucose is low compared to serum glucose.> Beta 2 transferring assay: This marker is very specific to CSF. However, the test is expensive & results may take several days to a few weeks to receive. Most leaks will have closed before the results are available, making this a poor test> Protein used in iron transport> Beta 1 - Serum, nasal secretions, tears, saliva> Beta 2 - CSF, perilymph and aqueous humor.> Diagnosis: History - surgeries, accident, unilateral, watery, intermittent, assocaited features like headache, positional variation, associated with anosmia or hyposmia etc.,> Laboratory Tests: Glucose oxidase test: Glucose oxidase strips show color change on detection of glucose (high false negative so abondoned) b2 transferring in the nasal secretions. In CSF Beta 2 transferring is present, and it is absent in normal nasal secretions. (100%sensitivity and 95% specificity. b Trace protection: 100% sensitive and specific Intrathecal radionucleotide test: Most specific Test that help to localise the CSF leak MR cysternography, CT Cysternography (Contraindicated in active meningitis or High ICP) Intrathecal administration of non-ionic contrast with high resolution CT scan. Intrathecal administration of low quantities of Fluorescein can also be used. If the leak is present it can be seen in the nasal cavity with a 490 nm light generated by a special optical filter. Dye injection is done using Barbolage technique in which 1-2 drops of 5% Fluorescein is diluted with the patients own CSF, and then injected partially, then CSF is withdrawn further diluting the dye and then reinjecting the dye.# CSF contains glucose which can be demonstrated by oxidase peroxidase paper strip or biochemical tests. Beta 2 transferrin is specific for CSF.> Analysis of the collected nasal fluid can be both problematic and useful. Analysis of nasal fluid is problematic because simple testing such as observing how the drainage dries on paper (Ring sign) or measuring the sugar content (reflecting the elevated glucose content of CSF) may not be valid.> Presence of the enzyme Beta2-transferrinase is only found in CSF, but requires the collection of several milliliters of fluid to be sent for highly specialized laboratory testing.> To confirm or further identify the route of CSF rhinorrhea, three forms of imaging are available.> Isotope cisternogram is the most sensitive, but least specific form of imaging. Nuclear medicine study consists of placing a low yield radioactive isotope in the subarachnoid space via a lumber puncture or spinal tap. Presence of isotope containing CSF in the nose is confirmed by measuring radioactivity within the nasal cavity or on cotton pledgets placed at probable sites of cerebral spinal fluid drainage from the cranial cavity. Contrast CT cisternography is a more specific, but a less sensitive form of imaging for CSF rhinorrhea. Requires an active leakage of CSF to the nose and involves the placement of an agent opaque to CT imaging within the subarachnoid space. Coronal CT scan is then performed to image the defect within the floor of the anterior or middle cranial fossa, and the route of drainage into the nose.> Magnetic resonance imaging is a non-radiographic procedure utilizing the detection of electromagnetic energy released from the hydrogen atom as the electron circling the nucleus descends to a lower energy level. Soft tissue contains various amounts of water and the physics of detecting changes in energy rather than density (as in the case of CT) significantly favor the former. MR imaging is the examination of choice tor visualizing potential brain anomalies, such as encephaloceles (herniation of brain into the nose or ear). MR also permits the identification of CSF draining into the nose without the use of contract, but does not visualize well bony detect in the skull base or currently lacks the detail provided by CT cisternography.
Beta 2 microglobulin
Beta 2 transferrin
Thyroglobulin
Transthyretin
Nervous System