International Consensus Statement: Spontaneous Cerebrospinal Fluid Rhinorrhea

Abstract

Background
The association between spontaneous cerebrospinal fluid (CSF) leak/rhinorrhea and idiopathic intracranial hypertension (IIH) has been increasingly recognized over the last years. However, considerable variability of opinion regarding the assessment, investigations, and management of patients with spontaneous CSF rhinorrhea remains.

Methods
A consensus group was formed from experts from Europe, Asia, Australia, South and North America. Following literature review and open discussions with members of the panel, a set of 61 statements was produced. A modified Delphi method was used to refine expert opinion with 3 rounds of questionnaires and a consensus group meeting in Santo‐Rhino meeting in September 2019.

Results
Fifty statements (82% of total) on spontaneous CSF leak and IIH reached consensus. In 38 of 50 statements, the median response was 7 (strongly agree) and in the 12 remaining statements the median response was 6 (agree). Eleven statements were excluded because they did not reach consensus and one new statement was added during SantoRhino meeting. The final statements refer to patient history and clinical examination ("History taking should include presence of headache, tinnitus and visual defects"), investigations (role of Thin Slice Computed Tomography and CISS/FLAIR sequences in Magnetic Resonance Imaging), principles of management (watchful waiting or measures to reduce ICP are supplementary but cannot subsitute surgical closure), surgical technique, intraoperative, early postoperative and long term management.

Conclusion
We present fifty consensus statements on the diagnosis, investigation, and management of spontaneous CSF rhinorrhea based on the currently available evidence and expert opinion. Although by no means comprehensive and final, we believe they can contribute to the standardization of clinical practice. Early diagnosis, prompt surgical closure of the defect, assesment for and treatment of potentially co‐existing idiopathic intracranial hypertension in a comprehensive multidisciplinary approach are essential in order to successfully manage spontaneous CSF rhinorrhea, reduce associated morbidity and prevent recurrence.

Full text

REVIEW ARTICLE
International Consensus Statement Spontaneous Cerebrospinal Fluid
Rhinorrhea
Christos Georgalas, MD, PhD, MRCS(Ed), DLO, FRCS(ORL-HNS), FEB(ORL-HNS) Hon1,2 ,
Amanda Oostra, MD MSc3, Ahmed Shahz, BSc(Hons), DLO, MBChB, FRCS (ORL-HNS), PhD4,
Paolo Castelnuovo, MD, FACS, FRCS(Ed)5, Iacopo Dallan, MD6, Wouter van Furth, PhD7,
Richard J. Harvey, PhD (Surgery) BSc(Med) MBBS(Hon1) FRACS FARS8, Philippe Herman, MD, PhD9,
Dimitrios Kombogiorgas, MD, MPhil, MRCSEd, FRCS(S/N),10, Davide Locatelli, MD PhD11 ,
Cem Meco, FEBORL-HNS12,13 , Jim N. Palmer, MD14 , Otavio Piltcher, MD, PhD15,
Anshul M. Sama, BMedSci, BMBSc, FRCS (Gen ), FRCS (OTOL)16, Hesham Saleh, MBBCh, FRCS, FRCS
(ORL-HNS)17,18 , Raj Sindwani, MD19, Thibaut Van Zele, MD, PhD20 and
Bradford A. Woodworth, MD21
Background The association between spontaneous
cerebrospinal fluid CSF leak/rhinorrhea and idiopathic
intracranial hypertension IIH has been increasingly recog-
nized over the last years However considerable variability
of opinion regarding the assessment investigations and
management of patients with spontaneous CSF rhinorrhea
remains
Methods A consensus group was formed from experts
from Europe Asia Australia South and North America Fol-
lowing literature review and open discussions with mem-
bers of the panel a set of  statements was produced
A modified Delphi method was used to refine expert opin-
ion with  rounds of questionnaires and a consensus group
meeting in Santo-Rhino meeting in September 
Results Fiy statements  of total on spontaneous
CSF leak and IIH reached consensus In  of  state-
ments the median response was  strongly agree and in
the  remaining statements the median response was 
agree Eleven statements were excluded because they did
not reach consensus and one new statement was added
during SantoRhino meeting The final statements refer to
patient history and clinical examination "History taking
should include presence of headache tinnitus and visual
defects" investigations role of Thin Slice Computed To-
mography and CISS/FLAIR sequences in Magnetic Reso-
nance Imaging principles of management watchful wait-
ing or measures to reduce ICP are supplementary but can-
not subsitute surgical closure surgical technique intraop-
erative early postoperative and long term management
Conclusion We present fiy consensus statements on the
diagnosis investigation and management of spontaneous
CSF rhinorrhea based on the currently available evidence
and expert opinion Although by no means comprehensive
and final we believe they can contribute to the standard-
ization of clinical practice Early diagnosis prompt surgical
closure of the defect assesment for and treatment of po-
tentially co-existing idiopathic intracranial hypertension in
a comprehensive multidisciplinary approach are essential
in order to successfully manage spontaneous CSF rhinor-
rhea reduce associated morbidity and prevent recurrence
© 2020 ARS-AAOA, LLC.
Key Words
idiopathic intracranial hypertension IIH spontaneous CSF
leak rhinorrhea consensus article |
How to Cite this Article
Georgalas C Oostra A Shahz A et al International con-
sensus statement spontaneous cerebrospinal fluid rhinor-
rhea Int Forum Allergy Rhinol -
1Endoscopic Skull Base Centre Athens, Hygeia Hospital, Erythrou
Stavrou 4, Maroussi Athens, 15123, Greece; 2Medical School, University
of Nicosia, 93 Agiou Nikolaou Street, Engomi, Nicosia 2408, Cyprus;
3Department of Neurosurgery, Evangelismos University Hospital
Athens, Athens, Greece; 4Department of ENT and Skull Base Surgery,
Birmingham Hospital, Birmingham, UK; 5Department of
Otorhinolaryngology, University of Insubria, Varese, Italy; 6Department
of Otolaryngology - Head and Neck Surgery, Azienda
Ospedaliero-Universitaria Pisana, Pisa, Italy; 7Department of
Neurosurgery, Leiden University Medical Center (LUMC), Leiden,
Netherlands; 8Sydney ENT clinic, Sydney, Australia; 9Department of
Otolaryngology, Hôpital Lariboisière, Paris, France; 10Department of
Neurosurgery, Hygeia Hospital, Athens, Greece; 11Neurosurgical Clinic,
Insubria University, ASST Settelaghi, Varese, Italy; 12 Department of
International Forum of Allergy & Rhinology Vol  No  xxxx  1

Georgalas et al.
Despite initial hesitance in establishing a link,1evidence
has gradually accumulated that idiopathic intracra-
nial hypertension (IIH) is associated with spontaneous cere-
brospinal uid (CSF) leaks.2–7 Patients with IIH and those
with spontaneous CSF rhinorrhea both tend to be female
and overweight and share specic radiographic ndings,
such as empty sella,6abnormalities of the optic sheath com-
plex, globe attening, encephaloceles, arachnoid pits, en-
larged Meckel’s cave,8and dural ectasia.9However, pa-
tients with spontaneous CSF rhinorrhea do not usually
complain of the typical symptoms associated with IIH.10
Hence, the diagnosis of concurrent IIH is usually conrmed
following closure of the skull-base defect: This will often
lead to increased intracranial pressure (ICP) and initiate the
typical symptoms of increased ICP.10
Understanding the link between IIH and spontaneous
CSF leaks is not of academic interest only: it has important
management implications. Indeed, this link could causal
link entail that controlling increased ICP may improve the
results of spontaneous CSF leaks repair and reduce recur-
rence rates.7However, there is signicant discrepancy - a
form of an “academic disconnect”- between the otolaryn-
gology, neurosurgical,1and neurology literature regarding
the management of spontaneous CSF leaks11–13. A signif-
icant number of otolaryngologists and neurosurgeons do
not acknowledge the link to IIH,14–18 hence missing the
change of diagnosing and treating IIH early.
An expert panel was convened, consisting of endoscopic
skull-base surgeons, otolaryngologists, and neurosurgeons
with interest in IIH and spontaneous CSF rhinorrhea from
11 countries (United States, Brazil, United Kingdom, Aus-
tralia, Italy, Greece, France, Belgium, Turkey, Austria, and
Cyprus) with the aim of producing a common set of state-
ments referring to the assessment, investigations, and man-
agement of spontaneous CSF rhinorrhea associated with
IIH. The size of the group was party dictated by the need to
meet in person in order to nalize the consensus document.
We do recognize that this could potentially introduce bias;
ORL-HNS, Ankara University Medical School, Ankara, Turkey;
13Department of ORL-HNS, Salzburg Paracelsus Medical University,
Salzburg, Austria; 14Otorhinolaryngology–Head and Neck Surgery,
Hospital of the University of Pennsylvania, Philadelphia, PA; 15ENT
Department, Hospital de Clinicas de Porto Alegre - UFRGS, Brazil;
16ENT Surgeon, Spire Nottingham Hospital, Nottingham, UK;
17Department of Otolaryngology - Head and Neck Surgery, Charing
Cross Hospital, London, UK; 18ENT Surgery, Imperial College, London,
UK; 19ENT Cleveland Clinic, Cleveland, OH; 20 Department of
Otorhinolaryngology, UZ Ghent University Hospital, Gent, Belgium;
21Department of Otolaryngology, University of Alabama at
Birmingham, Birmingham, AL
Correspondence to: Christos Georgalas PhD DLO FRCS(ORL-HNS),
Endoscopic Skull Base Centre Athens, Athens, Greece; e-mail:
cgeorgalas@gmail.com
Potential conict of interest: None provided.
Received: 13 May 2020; Revised: 8 September 2020; Accepted:
8 September 2020
DOI: 10.1002/alr.22704
View this article online at wileyonlinelibrary.com.
however, the representation of 11 different countries and 4
continents produced a diversity of voices and encouraged
open and healthy discussions.
Methods
The development of this consensus statement consisted of
9 steps: (1) panel recruitment including vetting of potential
conicts of interest; (2) determination of clinical evidence
gaps through a literature review; (3) qualitative survey and
development of initial set of statements with open feed-
back from members of the panel; (4) survey development
and administration (rst iteration); (5) revision of ambigu-
ous survey questions and removal or adaptation of remain-
ing statements; (6) re-survey (second iteration); (7) data ag-
gregation and analysis; (8) a consensus meeting during the
Santo-Rhino conference (September 2019, Santorini Island,
Greece; https://www.santorhino.eu/); and (9) third iteration
with production of nal statements.
An expert panel was convened consisting of neurosur-
geons and ear, nose, and throat (ENT) surgeons with sig-
nicant clinical experience and established academic repu-
tation in the management of spontaneous CSF rhinorrhea
and IIH. The choice of experts was done to be as repre-
sentative as possible and included a variety of disciplines
spanning 11 countries and 4 continents. The panel chair
(C.G.), along with designated panel members, led the sur-
vey and manuscript development using the modied Delphi
method.19
Literature review
Clinical gaps in the literature were sought through exist-
ing guidelines or evidence-based reviews. A supplemental
search that included systematic reviews (including meta-
analyses) or clinical practice guidelines in English from
PubMed and The Cochrane Library from 2000 to 2019
using the search terms “spontaneous CSF leak - rhinor-
rhea AND idiopathic intracranial hypertension” was also
included. The gaps in literature were used as a framework
for the Delphi surveys.
Creation of initial set of statements
Following literature review and open discussions with
members of the panel, an initial set of 61 statements was
produced. These statements were separated into 6 clini-
cal areas: (1) clinical examination; (2) investigations; (3)
management; (4) surgical technique; (5) intraoperative and
immediate postoperative management; and (6) long-term
management.
Delphi method
The Delphi method19 was utilised: This is a standardized
technique to dene expert opinion in a way that an equal
input from each expert is obtained while minimizing bias.
Authors were asked to state their opinion of the statements
in a 7-point Likert scale as follows: 1 =strongly disagree; 2
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International consensus statement
FIGURE 1. Iterations.
=disagree; 3 =somewhat disagree; 4 =neither agree nor
disagree; 5 =somewhat agree; 6 =agree; and 7 =strongly
agree.
Consensus was achieved when:
1. 80% of votes fell within 2 upper categories (6 agree or
7 strongly agree)20
2. AND there was no more than 1 outlier in the opposite
direction (3 somewhat disagree, 2 disagree or 1 strongly
disagree)
3. AND there was no more than 1 panel member who
skipped the question.
The Web-based software, Survey monkey (San Mateo,
CA) was used for sending the question rounds to the ex-
perts. For all questions within the survey, there was an
option for free text so that the participants could both
state the reason they disagree and suggest amendments.
An e-mail address was requested in the questionnaire in
order to ensure follow-up, but answers were deliberately
anonymized. Our Delphi process consisted of 4 rounds. In
the rst round, the initial 60 statements were sent using
an electronic questionnaire. Consensus was reached in 36
statements, whereas another 24 statements were amended
following comments supplied by the authors and sent for
second iteration. Consensus was subsequently reached in
11 of them. The third iteration took place in person at the
Santo-Rhino consensus meeting in September 2019, where
all statements were again discussed, ne-tuned, and 1 new
statement was added. Following the meeting, there was a
nal (fourth) Delphi round, during which 13 controversial
statements were sent in a third electronic questionnaire out
of which another 3 reached consensus (Total 50) (Fig. 1).
Results
A total of 50 statements, grouped into 6 categories, reached
nal consensus (Tables 1-6). In 38 of 50 statements, the me-
dian response was 7 (strongly agree) and in the 12 remain-
ing statements the median response was 6 (agree). Eleven
statements were excluded because they did not reach con-
sensus and 1 new statement was added during SantoRhino
meeting.
Discussion
Spontaneous CSF leaks can be challenging, both in their
diagnosis and localization as well as their long-term man-
agement. Our panel reached strong consensus (median 7)
in the vast majority of statements, reecting the strength of
recommendations and of overall agreement. This was most
prominent in the areas of management (principles of man-
agement, surgical technique, intraoperative and early post-
operative and long-term management), where every single
one of the 25 statements reached strong consensus (median
of 7).
History and clinical examination
CSF rhinorrhea should be suspected in cases of unilateral
watery rhinorrhea, especially if triggered by changes in pos-
ture or following head trauma or skull-base surgery. The 2
statements: CSF rhinorrhea should be suspected in rhinor-
rhea associated with salty rather than sweet taste and rhin-
orrhea that continues during bedtime, did not reach consen-
sus. It was believed that both answers, because they can be
present in a plethora of diseases, do not distinguish enough
to help with diagnosing CSF rhinorrhea.
Patients with an active CSF leak may (infrequently)
have symptoms of IIH (such as headache, visual defects,21
and pulsatile tinnitus22) but may also display symptoms
of decreased ICP such as orthostatic headache and neck
stiffness.23 Patients with spontaneous CSF leaks and IIH
are usually obese (body mass index [BMI] >30).24,25 Be-
yond nasal endoscopy, examination of the Eustachian tubes
and of the tympanic membranes can show an otologic cause
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Georgalas et al.
TABLE 1. History and clinical examination
#Statement Mode Median Range
Agree
(%)
Strongly agree
(%)
1CSF rhinorrhea should be suspected in patients with unilateral watery rhinorrhea 7 7 5–7 12 82
2CSF rhinorrhea should be suspected when rhinorrhea is triggered by changes in posture 6 6 5–7 47 47
3CSF rhinorrhea should be suspected when rhinorrhea is triggered by head trauma or skull-base surgery 7 7 6–7 12 88
History taking in patients with spontaneous CSF rhinorrhea should include symptoms of IIH such as:
4Presence of headache 7 7 4–7 29 53
5Presence of visual defects 7 7 2–7 41 47
6Presence of pulsatile tinnitus 7 7 3–7 38 50
7Patients with an active CSF leak may also present with symptoms of decreased ICP including
orthostatic headache and neck stiffness.
7 6 4–7 41 41
8Patients with spontaneous CSF leak/IHH are usually overweight (BMI >25) 6 6 2–7 59 30
9All patients with spontaneous CSF rhinorrhea should undergo a complete ENT examination including
nasal endoscopy
7 7 6–7 694
10 Clinical examination of someone suspected of having CSF rhinorrhea should include otologic exam
(fluid in the middle ear could indicate an otologic source for the CSF leak)
7 7 6–7 24 76
11 Examination of the Eustachian tube by endoscopy can be valuable when examining for an otologic
source for CSF rhinorrhea
7 6 4–7 35 47
12 In patients with spontaneous CSF leak ophthalmologic assessment including fundoscopy for
papilledema and assessment of visual fields is suggested
7 7 6–7 24 76
BMI =body mass index; CSF =cerebrospinal uid; CT =computed tomography; ENT =ear, nose, throat; ICP =intracranial pressure; IIH =idiopathic intracranial hypertension.
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International consensus statement
TABLE 2. Investigations
#Statement Mode Median Range
Agree
(%)
Strongly agree
(%
1Examination of the nasal fluid for beta2 transferrin/beta trace protein is an option if there is no obvious
identifiable defect and/or mechanism of CSF leak
7 7 6–7 18 82
2All patients suspected of spontaneous CSF rhinorrhea should undergo a high resolution (<1 mm slice)
CT scan of the sinuses and skull base without contrast
7 7 5–7 088
3In patients with suspected spontaneous CSF rhinorrhea a high resolution (<1 mm slice) T2
CISS/FIESTA-C and FLAIR or equivalent protocol MRI with coronal cuts should ideally be requested
for the assessment of the area of leak as well as signs of IIH
7 7 5–7 18 71
4FIESTA-C/CISS and FLAIR sequences in MRI can help differentiate between CSF (bright in CISS and dark
in FLAIR) and mucosal disease (bright in CISS, bright in FLAIR)
6 6 5–7 50 38
5Typical anatomical areas to examine for CSF leak in the CT scan include the lateral lamella/olfactory
cleft/ethmoid roof, the roof of the lateral recess of the sphenoid sinus (between foramen rotundum
and vidian canal), the supraorbital ethmoid roof/frontal sinus posterior table and the planum
sphenoidale as well as the posterior wall of sphenoid sinus and the temporal bone
7 7 6–7 24 76
6Patients with spontaneous CSF rhinorrhea/IIH may have multiple skull-base defects and areas of CSF
leak
7 7 5–7 12 82
Indirect features on brain CT/MRI suggesting increased ICP include:
7Empty sella 7 7 6–7 41 59
8Arachnoid pits/erosion of skull base 6 6 4–7 53 41
9Widening of the subarachnoid space around optic nerves and/or tortuous optic nerves 7 6 5–7 41 47
10 Posterior globe flattening 6 6 4–7 76 18
11 Dilated Meckel’s cave 6 6 2–7 63 19
12 Exclude a transverse venous sinus stenosis with an MRV (or CTV if MRV not available) either initially or
as second examination
7 6 4–7 41 41
13 In patients suspected of spontaneous CSF leak/IIH, optical coherence tomography is an option for
assessing early changes
6 6 4–7 59 35
CISS =constructive interference steady state; CSF =cerebrospinal uid; CT =computed tomography; CTV =computed tomography venography; FIESTA-C =fast imaging employing steady-state acquisition cycled
phases; FLAIR =uid attenuation inversion recovery; ICP =intracranial pressure; IIH =idiopathic intracranial hypertension; MRI =magnetic resonance imaging; MRV =magnetic resonance venography.
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Georgalas et al.
TABLE 3. Principles of management
#Statement Mode Median Range
Agree
(%)
Strongly agree
(%)
1Patients with proven (radiologically/beta trace–beta transferrin) CSF leak should undergo
closure, even if the leak is intermittent
7 7 6–7 19 81
2Such patients should be operated as soon as feasible (in view of the risk of meningitis) 7 6 4–7 38 50
3Once the diagnosis of a CSF leak is confirmed, the patient should be advised about the risk of
meningitis and informed about its symptoms and signs
7 7 6–7 694
4Watchful waiting or measures to treat the CSF leak by reducing ICP are supplementary and
cannot substitute surgical repair of the anatomical defect, if established
7 7 5–7 41 53
5Long-term treatment with oral antibiotics has not been shown to reduce the incidence of
meningitis and should not be given routinely to patients with CSF leak (when there are no
signs of infection)
7 7 6–7 35 65
CSF =cerebrospinal uid; ICP =intracranial pressure.
of CSF rhinorrhea, whereas an ophthalmology consultation
(including fundoscopy) may show early signs of IHH.
The statement “Having the patient perform a modied
Valsalva maneuver can be helpful in identifying a rhinology
source for a CSF leak,”did not reach consensus. Performing
a modied Valsalva maneuver was even considered to be
dangerous outside the operation theatre because it can lead,
in cases of large defects, to pneumocephalus.26,27
Investigations
In most cases appropriate imaging (high-resolution com-
puted tomography [HRCT]28,29, high-resolution magnetic
resonance imaging–uid attenuation inversion recovery
[MRI-FLAIR] and fast imaging employing steady state ac-
quisition [FIESTA] C/constructive interference steady state
[CISS] protocols)29,30 will localize the defect. At the same
time, they will identify indirect signs of IIH such as empty
sella, arachnoid pits, skull-base thinning,31 and tortuous
optic nerves with widened subarachnoid space32 Both nu-
clear cisternogram and CT cisternography do not provide
a benet over simple HRCT/heavily-weighted T2 MRI;
however, they are more invasive, less sensitive, and as-
sociated with more complications, as shown in a recent
metanalysis.33 MRI cisternography does no longer involve
intrathecal injection of contrast; instead it refers to heavily-
weighted T2W and gradient sequences such as 3D T2
driven equilibrium radiofrequency reset pulse (DRIVE),
balanced fast eld echo (B FFE) (Philips, Andover, MA),
CISS (Siemens Medical Solutions USA, Inc., Malvern, PA),
FIESTA (GE Healthcare, Piscataway, NJ), prone high-
resolution MRI.
Comparing the signal in FLAIR and CISS can help differ-
entiate between CSF (bright in CISS, dark in FLAIR) and
inammation/edema (bright in CISS, bright in FLAIR).
The use of beta trace34 and/or beta2 transferrin is
helpful35-39 to conrm the presence of CSF because they
can detect 5 μL and 100 μL of CSF in 1 mL of nasal se-
cretions, respectively. Beta2 transferrin test has a sensitivity
and specicity of over 90% whereas beta trace protein is
faster and cheaper to process and has a large CSF to serum
ratio, favoring it as a marker for CSF (sensitivity over 90%
and 100% specicity).35,38 The original statement “All pa-
tients suspected of CSF rhinorrhea should have the nasal
uid examined for beta trace protein or, if not available, for
beta transferrin” did reach consensus but also many com-
ments. Testing for beta trace protein is not readily available
in the United States and 4 colleagues mentioned not test-
ing for beta2 transferrin when the radiological and clinical
signs are obvious for a CSF leak. Accordingly, we decided
to change to the statement from the second Delphi round
onward to “Examination of the nasal uid for beta2 trans-
ferrin/beta trace protein is an option if there is no obvious
identiable defect and/or mechanism of CSF leak.”
Defects typically occur in the lateral lamella/olfactory
cleft/ethmoid roof as well as the roof of the lateral recess of
the sphenoid sinus25,39,40 (lateral to the foramen rotundum
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International consensus statement
TABLE 4. Surgical technique
#Statement Mode Median Range
Agree
(%)
Strongly
agree
(%)
1The use of intrathecal fluorescein is an option if the
area of defect cannot be localized preoperatively
or in suspicion of multiple areas of CSF leak and/or
to confirm complete closure—if used, it should not
exceed the maximum dose of 0.5 mg/kg of body
weight, slowly administered.
7 7 3–7 29 59
2The use of intraoperative neuronavigation with CT
(with or without MRI fusion) is recommended in
complex cases and can assist in localizing the
area of bony defect and associated CSF leak
7 7 5–7 31 63
A variety of techniques can be used for closure. Basic
principles include:
3Accurate localization of the defect 7 7 6–7 694
4Excision via bipolar cautery of the associated
meningoencephalocele, if present
7 7 4–7 688
5Removal of the mucosa around the defect and
freshening of the defect edges
7 7 6–7 694
6Application of graft materials (either homologous;
pedicled or free tissue graft or heterologous) in 1
or more layers, using inlay or onlay technique
7 7 4–7 12 82
7Securing and supporting the repair with
absorbable or non-absorbable materials including
glues and sealants
7 7 5–7 18 76
CSF =cerebrospinal uid; CT =computed tomography; MRI =magnetic resonance imaging.
TABLE 5. Intraoperative and early postoperative management
#Statement Mode Median Range
Agree
(%)
Strongly
agree
(%)
1As this is a clean–contaminated procedure a single
prophylactic dose of intravenous antibiotic during
the induction of anesthesia is strongly
recommended. The use of antibiotics in the
immediate postoperative period is an option.
7 7 6–7 18 82
2The use of lumbar drain is an option: It can be used to
inject fluorescein as well as to measure and
reduce ICP following closure and inform IIH
management; however, it requires robust
monitoring and may be associated with significant
complications including negative pressure
pneumocephalus.
7 7 3–7 35 59
3Patients should be admitted overnight and undergo
monitoring of vital and neurological signs.
7 7 5–7 29 65
4They are advised to remain recumbent for 12–24
hours following surgery in a 30-degree head
elevation position.
7 6 2–7 38 50
ICP =intracranial pressure; IIH =idiopathic intracranial hypertension.
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Georgalas et al.
TABLE 6. Long-term management
#Statement Mode Median Range
Agree
(%)
Strongly
agree
(%)
1Patients with IIH may develop new symptoms (visual
defects, headache) following defect closure
7 6 5–7 41 41
2In cases with suspected (history/radiology) increased
ICP, oral acetazolamide may be provided for 6
weeks postoperatively (until formal measurement
of ICP)
7 7 4–7 24 59
3The assessment of ICP should be considered (in
recurrent CSF leak/or revision surgery) following
defect closure: Either during the same admission
or postoperatively and after the discontinuation of
acetazolamide for at least 1 week.
7 7 5–7 18 65
4Cases of secondarily increased ICP should always be
excluded
7 7 4–7 29 53
5The definitive management of increased ICP (>25
mm CSF/H2O) should always be undertaken in
order to avoid recurrence of the leak and to avoid
the long-term sequelae of IIH.
7 7 4–7 35 53
6All overweight patients with IIH should be strongly
advised to lose weight
7 7 5–7 24 71
7The definitive management of IIH should always be
undertaken in collaboration with a
neurologist/neurosurgeon and could include either
conservative measures (weight loss,
acetazolamide) or surgical measures (CSF
diversion procedures including lumboperitoneal or
ventriculoperitoneal shunting)
7 7 2–7 18 71
8Prolonged (4–6 weeks) CSF leak precautions should
be instituted postoperatively to reduce the risk of
recurrence. These include avoidance of nose
blowing, bending over, strenuous activity or heavy
lifting (>15 pounds/7 kg)
7 6 5–7 47 47
9Flying is discouraged for the first weeks after surgery
and diving for the first 6 months
7 7 1–7 18 76
CSF =cerebrospinal uid; ICP =intracranial pressure; IIH =idiopathic intracranial hypertension.
and vidian canal)41–43—both areas of reduced weakness
of the skull base. Additionally, the supraorbital ethmoid
roof/posterior table of frontal sinus/planum sphenoidale as
well as posterior wall of sphenoid sinus and the tempo-
ral bone can be areas of spontaneous CSF leak.44 It is not
unusual for patients with spontaneous CSF rhinorrhea/IIH
to have multiple skull-base defects and/or areas of CSF
leak.45 The intraoperative use of intrathecal uorescein can
be useful to localize the leak, identify multiple defects, and
conrm watertight closure at the end of the procedure.30
In cases of increased ICP, magnetic resonance venography
(MRV) (or computed tomography venography [CTV]) may
exclude transverse venous sinus stenosis,46 and optical co-
herence tomography (OCT) may show early changes to the
optic apparatus.47
Management
There was a strong consensus of the panel that CSF leaks,
even if intermittent, must be closed as soon as feasible,48
and there is no role for a watchful waiting policy, or for ICP-
lowering procedures as a substitute for closure.49,50 Due to
difculty in logistics in different countries, we have to re-
frain from using a certain time frame because this is a re-
quired procedure but not an immediate emergency. Simi-
larly, the long-term use of antibiotics has not been shown
to reduce the incidence of meningitis and cannot substitute
surgical closure.
Surgical technique and immediate management
There are a variety of materials and techniques that can be
used to effectively close a defect—and there is little evidence
8International Forum of Allergy & Rhinology Vol  No  xxxx 

International consensus statement
that one is superior to another. Basic principles that apply
include accurate localization, excision of associated menin-
goencephalocele (if present) and removal of mucosa around
the bony defect.44,51 Additionally, the use of intraopera-
tive navigation and/or intrathecal uorescein can be use-
ful in more complex cases. The use of lumbar drains is op-
tional; the potential therapeutic benet and measurement
of opening pressures must be carefully weighed against its
considerable complications.52,53 Day-case CSF leak repair
is strongly discouraged, despite some limited and mostly
anecdotal experience in its use,54 and admission overnight
with appropriate monitoring is recommended. In complex
cases (giant meningoencephaloceles, large defects, or mul-
tiple associated pathologies) the statement that a CT brain
should be considered during the rst 24 hours after surgery
was rejected after the second Delphi round. Multiple ex-
perts had the opinion that clinical evaluation is more im-
portant and without clinical deterioration the CT scan
can be performed after 24 hours, whereas 7 of our ex-
perts do perform a CT scan in these specic cases within
24 hours.
A signicant part of our patients are obese with obstruc-
tive sleep apnea (OSA). Although there is very little evi-
dence, most agree that the use of continuous positive air-
way pressure (CPAP) devices should be discouraged for the
rst 2 to 3 postoperative weeks,55 depending to the size of
defect as well as the severity of OSA.56
Long-term management
Notably, patients may develop IHH symptoms
(headache, visual defects) following defect closure,57 and
acetazolamide58 may be useful postoperatively. However,
patients may have longstanding intracranial hypertension
without visual symptoms,5which suggests that manage-
ment of high ICP is needed even in the absence of symptoms
in order to prevent subsequent CSF leaks. Patients with
spontaneous CSF rhinorrhea should be considered for ICP
assessment (either during admission or later postopera-
tively and after the discontinuation of acetazolamide for
at least 1 week) following closure of the defect, and if
IIH is conrmed, this must be denitively managed50,59,60
(weight loss,61 acetazolamide, lumboperitoneal, or ven-
triculoperitoneal shunt62 in collaboration with a neurolo-
gist/neurosurgeon) in order to avoid recurrence,7as well as
to avoid complications of untreated IHH. Recent (2018)
consensus guidelines on the management of IIH63 provide
a relevant owchart: weight management advice should be
offered for all patients with IIH, whereas patients without
immediate threat to vision can be initially managed with
acetazolamide. However, if vision is threatened, CSF diver-
sion (preferably ventriculoperitoneal shunt, which has a
lower reported revision rate as per meta analysis64)oroptic
nerve sheath fenestration should be performed. Surgery
is always indicated in cases where medical management
does not adequately treat vision impairment or pressure
remains elevated. The role of other medications (such as
topiramate65 an appetite suppressor that is also a carbonic
anhydrase inhibitor65) remains poorly dened: there is
paucity of data on their use in patients with IHH.
Conclusion
In summary, we present fty consensus statements on diag-
nosis, investigations and management of spontaneous CSF
rhinorrhea based on currently available evidence and expert
opinion. Although by no means comprehensive and nal,
we believe they can serve as a useful tool that will contribute
to standardization of clinical practice. Early diagnosis and a
comprehensive multidisciplinary approach are essential in
order to successfully manage spontaneous CSF rhinorrhea
and reduce the associated morbidity and recurrences.
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