CerebroSpinal Fluid Rhinorrhoea is the leakage of CSF from the subarachnoid space into the nasal cavity due to a skull base defect. CSF leaks can be caused by trauma, tumors, congenital defects, or idiopathic increased intracranial pressure. Diagnosis involves analyzing fluid samples for beta-2 transferrin or beta-trace protein and imaging studies using intrathecal dyes. Treatment begins with conservative measures to reduce CSF production and pressure but often requires surgical repair via an endoscopic, extracranial, or intracranial approach depending on the location and size of the defect. Endoscopic techniques have high success rates with less morbidity compared to open cranial

1. CerebroSpinal Fluid Rhinorrhoea
By: Dr. Jinu v iype
3rd year PG
Department of ENT

2. References:
• Scott Brown 7th edition & 8th edition
• Guyton textbook of physiology
• Cummings otolaryngology head and neck surgery
6th edition
• Hathiram- atlas of operative otorhinolaryngology
vol 2
• Zahir hussain 4th edition

3. CSF BASICS
• Cerebrospinal
fluid (CSF) is a
clear, colourless
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.

6. • Total volume of CSF varies from 90 to 140
ml.
this includes 20 mL in the ventricles,
50 mL in the intracranial subarachnoid
space,
70 mL in the paraspinal subarachnoid
space.
• It is secreted @ rate of 0.35-0.4 mL per
minute, that 50% of the CSF is replaced in 5
to 6 hours.

7. • The typical upper limit of normal CSF pressure
ranges from
40 mm H2O in infants
140 mm H2O in adults.
• when one is lying in a horizontal position
averages 130 millimeters of water
• CSF pressure fluctuates with respirations and
arterial pulse pressures as well as with changes
in head position.

8. • Pressure is maintained by balance between
CSF secretion and its resorption by the
arachnoid villi.
• Because CSF secretion occurs at a steady rate,
the rate of CSF resorption plays the major role
in determining CSF pressure.
• Processes that disrupt CSF resorption will
tend to lead to increased intracranial pressure.

9. Osmolartity (mosm/kg water) 280 280
145-155
2-3.5
15-45
45-85
pH 7.3- 7.4

10. DEFINITION
• Cerebrospinal fluid (CSF) rhinorrhoea is the
leakage of CSF from the subarachnoid space into
the nasal cavity due to a defect in the dura, bone
and mucosa.
• The origin of the
fluid may be from
the anterior,
middle or
posterior cranial
fossae.

11. History
• Dandy(1926): first surgical repair of CSF leak
via frontal craniotomy approach
• Wigand (1981): use of endoscope for the first
time to assist with repair of skull base defect
90-95% success rate with decreased
associated morbidity – thus preferred

12. AETIOLOGY
The importance of accurate classification was
first recognized by Ommaya et al proposed
dividing CSF rhinorrhea into
Ommaya Classification
Traumatic Non traumatic leaks

14. HEAD TRAUMA
• CSF leaks -2% of head injuries and 12% to 30%
of skull base fractures.
• Most CSF leaks occur as a result of blunt
trauma.
CSF otorrhea
CSF oto-rhinorrhea
CSF rhinorrhea.
• Most traumatic CSF leaks will heal with
conservative treatment including bedrest.

15. • It is likely that only the sinus mucosal aspect of
the defect closes as the dura does not
regenerate.
Leads to risk of meningitis
‘mono-layer of protection’ may be eroded
by either the pulsatile effect of the brain or
by inflammation within the nose.

16. • With the Massive head trauma with complex
comminuted and displaced fractures of the
skull base can be incredibly difficult to treat.
Open approaches may be useful.
• In massive ‘egg-shell’
fractures of the sphenoid
sinuses,
fat obliteration can
be considered,

17. CONGENITAL CSF LEAKS
• Encephalocele

18. • Meningoencephaloceles

19. • Mondini Dysplasia
may present with
substantial CSF
leaks where the
CSF has only
briefly transversed
the perilymphatic
space.
– presenting as
hearing loss
– recurrent
meningitis
– CSF otorrhea or
CSF oto-rhinorrhea

20. CSF LEAKS ASSOCIATED
WITH TUMOURS
• Tumours causing substantial erosion of the
skull.
• Tumour shrinkage occurs, for example during
induction chemotherapy.

21. SPONTANEOUS LEAKS
• Sometimes described as ‘idiopathic’
• The association of spontaneous leaks
– Middle-aged women with a raised body mass index.
– Variant of benign intra-cranial hypertension
Elevated intra-cranial pressure.
this diagnosis being made on lumbar puncture
after surgical repair.
• Not possible to measure this pre-operatively as the
persistent leak reduces the pressure.

22. • Radiological features of increased intra-cranial pressure such
as an empty sella, enlarged ventricles or diffuse erosion of the
skull base
• Spontaneous
leaks are most
likely to recur
• Success rates
for endoscopic
closure are
worse than for
other causes

23. Benign intracranial hypertension
• Also known as idiopathic intracranial
hypertension and pseudotumor cerebri, is a
syndrome of increased ICP
in the absence of specific causes such as
intracranial masses
hydrocephalus
dural sinus thrombosis

24. CSF LEAKS COMPLICATING
SINUS SURGERY
• CSF leaks complicating sinus surgery,
diagnosed intra-operatively should be repaired
under the same anaesthetic.
• Local intra-nasal tissue can be used for the
repair with generally good results.

25. • The most likely anatomical sites for CSF leaks
complicating sinus surgery
very thin bone of the lateral lamella of the cribriform
plate
Anterior skull base
where it is weakened
by the anterior ethmoid
neurovascular bundle
Posteriorly where
there may be confusion
as to the exact
anatomical relationship
between the last
posterior ethmoidal
cell and the sphenoid
sinus.

27. Other sites of CSF leak during FESS
• Olfactory fossa(Keros classification- type 3)
• Upper attachement of uncinate process
attached to Skull base
• Posterior wall of frontal recess

28. salty or metallic taste

30. • Halo sign has been considered an important
marker of CSF rhinorrhea after head trauma.
The halo sign is
considered present
when a clear ring
surrounds a central
bloody spot after
bloody nasal discharge
is dropped upon a
handkerchief or paper
towel.
Presence of either tears
or saliva is likely to give
a falsely positive halo
sign.

31. INVESTIGATION OF CSF LEAKS
• An accurate history
• Examining the patient including nasal
endoscopy.
• The investigations include:
• laboratory investigation of rhinorrhoea fluid;
• imaging;
• intrathecal dyes and markers.

32. Laboratory investigation
obtain fluid for testing-
Postural provocation
Run up stairs - increase intra-
cranial pressure and produce
drainage
strain on a closed glottis

33. 1) The only test that should be used to determine
CSF = immunofixation of beta-2 transferrin.
• Beta-2 transferrin is a protein involved in ferrous
ion transport and it is also found in perilymph
and aqueous humour.
Sensitivity test Specificity
100 % 95 %

34. • False-positive Beta-2 transferrin :-
• Chronic liver disease
• Inborn errors of glycogen metabolism
• genetic variant forms of transferrin
• Neuropsychiatric disease
• Rectal carcinoma
Abnormal transferrin metabolism thus the beta-2
form can appear in the blood

35. 2) beta-trace protein(βTP) is an even better test
than beta-2-transferin in detecting CSF leaks
βTP is produced by the meninges and choroid
plexus and is released into CSF.
It is also present in other body fluids, including
serum, but at much lower concentrations than
in CSF.
βTP has 100% sensitivity and specificity in
cases of confirmed CSF rhinorrhea.

36. • βTP false positive result
-renal insufficiency
– bacterial meningitis
3) Another CSF marker protein
transthyretin detected by a rapid on-chip
immunosubtraction technology.
Advan: results within 5 to 10 minutes,

37. Cerebrospinal Fluid Tracers
• Intrathecal agent tests
– provide information that can confirm the presence of
a CSF leak;
– location of the skull base defect associated with the
CSF leak.
All of these tests (except for those based on MRI)
require a lumbar puncture for the introduction of a
tracer agent into the subarachnoid space.
 Complications caused by the intrathecal agent can be
quite severe.

38.  Agents may be categorized
visible dyes
radionuclide markers
 radiopaque dyes.
 Any of these tests are considered
positive if the agent is visualized within
the nose and paranasal sinuses.

39. Intrathecal fluorescein
• It is probably the most popular
visible agent.
• Lumbar puncture is performed
for the introduction of
fluorescein into the intrathecal
space, the patient is kept in the
head-down position, and nasal
endoscopy is performed to
identify fluorescein within the
nose and sinuses.
• Fluorescein has a characteristic
green color- identify even in
minute.
• Specific blue-light filters may
be used to enhance visual
detection of fluorescein,

40. Complications: seizures
knee and ankle clonus
cranial nerve defects, death
• Low doses -recommended
dilution of fluorescein- 0.1
mL of 10% fluorescein in
10 mL of the patient’s own
CSF;
• Not an FDA-approved
application.

42. Radionuclide tracer
• Radioactive iodine (131I) serum albumen(RISA)
• technetium (99mTc)-labeled serum albumen
• DTPA(diethylene-triamterene-penta-acetic acid)
• indium-111 labelled DTPA
• Can be useful only in active CSF leak

43. • used for radionuclide cisternography,
• intrathecal administration of a radionuclide
tracer via a lumbar puncture
• monitoring of the distribution of tracer with a
scintillation camera.
• intranasal pledgets
are also placed
proximity to the
suspected skull
base defect
• assayed for tracer
12 to 24 hours
later with a gamma
counter.

44. Computed tomography (CT)
cisternography
• CT imaging after the intrathecal administration
of radiopaque contrast (metrizamide)
• Approximately
80% of CSF leaks
can be confirmed
through CT
cisternography.

45. • High resolution coronal CT scans (l-2-
mm slices) can offer detection in up to 84
%
• Axial views are helpful in detecting leaks
from the posterior wall of the frontal
sinus and sphenoid sinus.

46. Magnetic resonance (MR)
cisternography
• Noninvasive method to assess for the
presence of intranasal / intrasinus CSF
MRl is advisable in the
case of
encephalocoeles to
delineate the contents
and vascularity of the
sac before surgical
exploration

48. MANAGEMENT
Conservative surgical managements

50. CONSERVATIVE TREATMENT
• Duration- 1- to 2-week period
• The goal of these measures is to reduce the CSF leak flow
by decompressing the intracranial pressure; in this way,
healing at the defect site may seal the leak without surgical
intervention.

51. • Drug that reduce CSF production rate:
– Frusemide
– Acetazolamide 250mg once daily
• Side effect:
–Metabolic acidosis
–Hypokalamia
–Drowsiness

52. Lumbar drains
• CSF cell counts, protein, glucose, and cultures
should be sent daily-evaluation and pathology.
• An hourly drainage rate of 10 mL is desirable.
• Higher rates may lead to abnormally low ICP, which
can produce severe headache.
• Low ICP also may cause pneumocephalus because
air is drawn through the skull base defect.
• If low ICP is suspected,-> the rate of drainage
should be decreased/the drain should be clamped
until the ICP equilibrates at a higher level.
Prophylactic antibiotic should be used

53. • After craniotomy, the defect site is identified
• a tissue graft is placed to close the defect.
• Fascia lata grafts, muscle plugs, and pedicled
galeal flaps may be used.
• A tissue sealant- fibrin glue,
may be used
TRANSCRANIAL TECHNIQUES

54. • Access to the cribriform plate region and roof
of the ethmoid -> frontal craniotomy;
• access to the sphenoid sinus defects ->
extended craniotomy and skull base techniques
• Complications:
brain compression
hematoma
seizures
anosmia.
• Despite direct access to the skull base defect,
failure rates are quite high> 25%.

55. Advantages of Intracranial Approch
1. Direct visualization of the defect
2. Better chance of patching the defect in case of
high ICP

56. Disadvantage of intracranial approach
1. Not good visualization of the sphenoid sinus
2. Chance of following morbility
1. Anosmia
2. Bleeding
3. Seziures
4. Osteomyelitis of frontal bone
5. Frontal lobe dysfunction – Memory loss

57. EXTRACRANIAL TECHNIQUES
• This remains the method of choice for accessing
most leaks of the posterior wall of the frontal
sinus

58. • approaches described are as follows:
– via an external ethmoidectomy for access to the
cribriform plate and fovea ethmoidalis
– transmastoid for defects in the tegmen and petrous
temporal bone
– transseptosphenoidal for access to the sphenoid
sinus
– via a coronal or eyebrow
incision to the frontal
sinus using an
osteoplastic flap.

59. • In the frontal and sphenoid sinuses the mucosa
can be removed,
• the defect patched with a fascial graft and the
sinus can be obliterated by packing with fat.
• To support the graft
– pedicled or free mucosal grafts from the nasal
septum or turbinates

60. Complication:
– facial numbness
– septal perforation
– orbital complications- diplopia and epiphora.
The success rates vary from 76 to 100%
An extradural approach -minimizes the
incidence of intracranial complications.

61. ENDOSCOPIC REPAIR OF CSF
RHINORRHEA
• This is the method of choice for repairing the
majority of CSF leaks.
• Success rates are excellent at 76-97 %
• The grafts described include
– nasal mucosal flap
– free graft of nasal mucosa
– turbinate bone
– conchal
– septal cartilage
– temporalis fascia and fascia lata

62. Different type of graft
• Middle turbinate flap: Is a posterior pedicle
flap with sphenopalatine vessels.

63. • Upper septal mucoperiosteal flap

65. Leakage from cribriform plate /
Ethmoid roof
• Procedure: Done under GA
1. Graft harvesting
– Temporalis fascia is harversted
– Fat harvested from the ear lobule
– Septal cartilage
2. Site of leak identified
-Evidence of pulsation transmitted from cranial
cavity
-flow of thin and clear fluid from suspected area
-Fluorescein seen

66. 3. Edges of the margin freshened
4. Fat is tied with vicryl suture and positioned into
the defect “ bath plug” technique
5.Suture material passed through
septal cartilage

67. 6. Temporalis fascia
tucked under the mucosal
edge- UNDERLAY
TECHNIQUE
7. Graft is held in place
fibrin glue and supported
by gelform
8. Nasal pack with
merocel is done

69. Advantage of Endoscopic Procedure
1. Better Magnification and visualization
2. Absence of external scar
3. Minimal invasive procedure
4. Avoid dreadful complication with intracranial
approch

70. COMPREHENSIVE MANAGEMENT
STRATEGY
• Indications for operative CSF leak repair :-
failed conservative management
intraoperative recognition of a leak during sinus
surgery
skull base surgery or craniotomy
large defects or leaks
pneumocephalus
spontaneous leaks
open traumatic head wounds with CSF leakage.

71. • It is practical to consider management options in
four scenarios:
1) nonsurgical traumatic etiology,
2) intraoperative injury with immediate recognition
/onset,
3) operative injury with delayed recognition /onset,
4) nontraumatic, so-called spontaneous leaks.

72. Nonsurgical Traumatic Etiology
• Result of head injury - If the rhinorrhea does
not resolve within several days, operative
exploration and repair are necessary.
• Extracranial endoscopic techniques are
applicable; however, open transcranial
procedures may be warranted.

73. Intraoperative Injury with
Immediate Recognition or Onset
• If a CSF leak is suspected during FESS,
surgeon should confirm the presence of leak
repair should be performed.

74. Operative Injury with Delayed
Recognition or Onset
• After nasal surgery, the presence of CSF
rhinorrhea may not be confirmed until days,
weeks, months, or even years
A trial of conservative therapy given
some of these leaks will close with these simple
measures.
Surgical exploration

75. Nontraumatic Leaks/ spontaneous leak
• Nontraumatic CSF leaks -> require surgical
repair.
• Treatment of nontraumatic CSF rhinorrhea as a
result of
neoplasm
hydrocephalus

76. Complications of CSF leak repair
• Meningitis
• Pneumocephalus
• Brain abscess
• Epidural abscess
• Subdural abscess
• Intra cranial bleeding
• Postop Infection
• Formation of scar tissue in sinuses – c/o Nasal
obstruction

77. 1. Meningitis
• Most common complication.
• Casused by ascending infection from the sinus
– involving the meninges and csf space
• Symptoms:-
– Headache
– Photophobia
– Vomiting
Tx: 1.Cephalosporins(2nd n 3rd generation)*10days
2. Dexamethasone(0.6mg/kg/day * 5days)

78. 2. Pneumocephalus
• Collection of air in the cranial cavity-
Subarachnoid space.
• Occurs when air trapped when acutely
coughing, sneezing, nasal blowout
• C/F : Sudden alteration in mental status,
Confusion
• Tx:- Needle aspiration- burr hole

80. Cause of failure of surgery
1. Raised ICP
2. Infection
3. Intraop Bleeding

81. CONCLUSION
• CSF rhinorrhea occurs when a skull base defect permits the
drainage of CSF from the intracranial space to the nose and
paranasal sinuses.
• traumatic and nontraumatic.
• Diagnosis- β-transferrin assay.
• Several CSF tracer studies are available
• High-resolution CT / MR/ CT cisternography
• Many CSF leaks respond to conservative management
• Transcranial techniques for CSF leak closure have been present
for many decades, they are often a second-line treatment in the
contemporary management of CSF rhinorrhea.
• Extracranial techniques were developed in the middle of the
twentieth century
• Endoscopic repair the preferred surgical modality
for those instances in which operative repair is warranted.

82. Thank you!