Systematic Review

By Dr. Kavitha Nirmal Kumar , Prof. Balasubramanian Thiagarajan
Corresponding Author Dr. Kavitha Nirmal Kumar
Otolaryngology Stanley Medical College, - India
Submitting Author Dr. Balasubramanian Thiagarajan
Other Authors Prof. Balasubramanian Thiagarajan
Otolaryngology Stanley Medical College, - India 600029


CSF rhinorrhoea, CSF leak

Nirmal Kumar K, Thiagarajan B. Cerebrospinal Fluid Rhinorrhoes an Overview. WebmedCentral OTORHINOLARYNGOLOGY 2012;3(5):WMC003382
doi: 10.9754/journal.wmc.2012.003382

This is an open-access article distributed under the terms of the Creative Commons Attribution License(CC-BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Submitted on: 16 May 2012 11:06:03 AM GMT
Published on: 19 May 2012 09:50:32 AM GMT


This article discusses etiopathogenesis, clinical features and management of cerebrospinal fluid rhinorrhoea.

Cerebrospinal fluid rhinorrhoea is the leakage of cerebrospinal fluid from the subarachnoid space into the nasal cavity due to defect in both dura and bone.

Various causes of CSF rhinorrhoea include:

1. Traumatic
2. Iatrogenic
3. Idiopathic
4. Tumors


CSF is formed primarily in the choroid plexus found in the lateral, third and fourth ventricles. Extra choroidal formation of CSF is from the paranchymal capillaries and from intra cellular water metabolism

CSF flows from its production sites in the two lateral ventricles through the foramina of monro into the third ventricle and to the fourth ventricle through the aqueduct of sylvius. Flow continues through the fourth ventricle, located in the brain stem and communicates with the cisterna magna through the midline foramina of Luschka from the cisterna magna. CSF flows into the subarachnoid space. CSF is absorbed into the cerebral venous system through the arachniod villai.

CSF is formed at the rate of 0.35ml/min1,6 or 350-500ml / day and it varies with circadian rhythum. The total volume of CSF is turned over about three times a day. The normal CSF pressure is 5-156 mm Hg or 5-15 cm water in prone position and increases to 40 cm of water with movement into sitting position. CSF pressure varies with the time of the day, age of the patient, activity level, respiratory and cardiac cycles. Neurologic systems may develop when the pressure higher than 20cm of water is sustained.
Functions of CSF

- Physical support and buoyancy for the brain.
- Maintain safe intracranial pressure.
- Removal of byproducts of metabolism.
- Regulate the chemical environment of the brain.

Etiology and classification

CSF Rhinorrhoea is classified according to the etiology developed by omaya. He divided CSF Rhinorrhoea into traumatic and non-traumatic. subdividing the latter into non –traumatic with normal pressure and non traumatic with high pressure.

Classification of CSF Rhinorrhoea

Traumatic causes

- Accidental
- Surgical

Non traumatic causes

- High pressure leaks



- Normal pressure leaks

Congenital anomely
Traumatic CSF Rhinorrhoea

Accidental Trauma
Accidental trauma in the most common etiology (80%)12 of CSF leaks. Leaks occur in 2-3% of patients with closed head injury and it 30% of patients with skull base fractures. CSF rhinorrhoea may occur directly through the anterior cranial fossa or indirectly from the middle or posterior fossa through the eustacian tube. Most frequent sites of CSF rhinorrhoea are Fovea ethmoidalis, Cribriform plate posterior wall offrontal sinus and Spheniod sinus. Because the anterior cranial fossa dura adherent to the bone is easily torn by fractured bone edges and the point where the anterior ethmoidal artery enter the lateral lamella in the place of least resistance in the entire skull base that a CSF fistula can occur .

In some patients avulsion of olfactory fibres from the cribiform plate by the shearing forces of a blunt trauma can rarely cause rhinorrhoea in the absence of fracture . Transverse fractures through the petrous bone cause CSF leak in to the middle ear and drain through the eustacian tube to the nasopharynx (Otorhinorrhoea). Rarely a cranio orbital fracture together with the laceration of conjuctival sac may cause CSF to leak from the eye (Occulo Rhinorrhoea )2,13

Traumatic CSF rhinorrhoea

Traumatic CSF rhinorrhoea usually begins within 48 hours of injury in 55%2 of the patients. The frequency increases to 70% by the end of first week. If the defect is small the bone may heal and in 60-70% of cases spontaneous healing occur within a week. Healing is unlikely to occur if

- The bone defect is large.
- Dura is penetrated by bony spikes
- Tissue healing is impaired by metabolic disease
- Increase in intra cranial pressure.

The onset of CSF may be delayed or recur after a period of cessation possible reasons for this are

- Lysis of blood clot at the fracturerd site
- Resolutions of soft tissue edema.
- Maturation and shrinkage of the dural scar
- Devascularisation and necrosis of the bone and soft tissue.
- Intermittent pulsations causing herniation of dura through a non-healed fractured site

Surgical trauma

Surgical procedures cause approximately 16% of csf rhinorrhoea . With the development of new surgical procedures,the etiology has changed and now the incidents of iatrogenic CSF rhinorrhoea has increased.In the past the majority of iatrogenic fistulas are due to neurologic surgeries and now the endoscopic sinus surgery is the leading cause for CSF rhinorrhoea (0.5-0.3%) 7,12.

The two most common sites of skull base injury associated with FESS are lateral lamella of cribriform plate and posterior ethmoid roof near the face of the sphenoid.Injury to lateral lamella of cribriform plate can occur during an approach to anterior ethmoids or frontal recess or when resecting the middle turbinate close to the skull base. Posterior ethmoid defects occur typically in highly pneumatised maxillary sinus that extends superomedially causing decrease in posterior ethmoid pneumatisation.

The most common cause of rhinorrhoea following neurologic surgeries are transsphenoidal management of pituitary tumours (0.5 – 15%)7,surgeries for acoustic neuroma (7-11%),Cranio facial resection and transcranial approaches.

Post surgical traumatic CSF rhinorrhoea may be present during immediate post operative period in 50% of patients.

Non-traumatic CSF rhinorrhoea

Non traumatic CSF rhinorrhoea is subdivide into high pressure and normal pressure leaks commonly occurs in adult females aged more than 30 years.

High pressure CSF Rhinorrhoea

In the high pressure leak the leakage of CSF is usually acting as a safety valve there by reducing the Intra cranial pressure which commonly occur in cribriform plate and roof of ethmoid. In such cases closure of the defect will worsen the patient condition if the causative lesion is not treated. Increased CSF pressure results from tumours or hydrocephalus. Tumours may cause CSF rhinorhoea either through direct erosion of bone or indirectly through pressure erosion. Treatment for the tumours such as surgery, irradiation or chemotheraphy can cause devascularisation of the tumour bed and skull base defect .

Normal pressure CSF Rhinorrhoea

In non traumatic CSF rhinorrhoea occurs in normal pressure system probably results from normal physiologic increase in CSF pressure .The increase in CSF pressure generally is not able to erode the bone, the presence of sudden, increase in intracranial pressure caused by coughing or straining may be an important precipitating factor in the development of spontaneous CSF rhinorrhoea.

- Normal pressure leaks may result from congenital defects such as,preformedpathways,fistulas,meningoceles,meningoencephaloceles or encephoceles .
- The empty sella syndrome occurring because of an absent portion of the diaphragma sellae is classified as congenital.The empty sella syndrome occurring because of pituitary gland atropy or degeneration is classified as spontaneous.
- Ostetis or osteomyelities of skull base bone may cause CSF rhinorrhoea infrequently.

Clinical features

  • CLEAR NON –STICKY FLUID DRAINING FROM THE NOSE sometimes rarely confused with allergic or vasomotor rhinitis. In traumatic cases CSF is mixed with blood. Some patients may complain of salty taste (because of sodium content ) of CSF or even a sweat taste (CSF has two thirds of Blood sugar). The amount of discharge may be continuous and copious in patients with non traumatic fistula then in patients with traumatic fistula for whom the leak is intermittent and scanty. CSF may accumulate in the sinuses when the patient is in supine position and then discharge through nostril when the head is flexed (Reservoir sign). If CSF leaks occur when the head is upright (or) tilted backwards suggests that the leak is through the cribriform plate, ethmoid roof or frontal sinus. Leakage occurs on tilting the head forward suggests that the leakage is from the sphenoid sinus or through the middle ear. CSF leak may be unilateral or bilateral but this does not always correspond to the site of the fistula.


Head ache can be either high pressure or low pressure type. In high pressure head ache there will be steady increase in pain which is relieved by fluid drainage and in low pressure head ache the pain is less marked in recumbent position and are increased by the upright position which results from acute or chronic leak. In some patients headache can be caused by intra cranial air.


Hyposmia or anosmia is due to olfactory nerve damage from fracture of the cribriform plate.


Infection alone may be the first sign of fistula without history of CSF Rhinorrhoea, most of the patients are belong to the delayed post traumatic group. Possible explanations for this are,

  • Age related shrinkage of brain previously pluging a defect.

  • Cerebral – dural scar that sealed the scar did not provide reliable barrier to infection.

  • Growing fractures of the ethmoid leading to the formation of a herniated encephalocele that stretched and ruptured as a result of intracranial pulsations.



A clear watery fluid leakage from the nose is likely to be CSF. If the fluid is mixed with blood or nasal discharge the presence of CSF is indicated by halo sign. The discharge is placed on filter paper CSF will migrate farther and form ring like pattern around the blood and mucus in the centre.


A wet hand kerchief that dries without stiffening suggestive of CSF leak.


The test strips are positive at a relatively low level of glucose. Reducing substances in the lacrimal gland secretions and nasal mucus may cause a positive reaction. Hence a negative test excludes the present of CSF but a positive result cannot be interpreted except in the presence of CSF infection.

Laboratory tests


  • Beta-2 transferrin is highly sensitive and specific in identifying fluid as CSF.

  • Beta -2 transferrin is a polypeptide involved in ferrous iorn transport.

  • It is produced by desialisation of the normal Beta -1 transferrin in CSF through cerebral neuraminidase. It is found only in CSF, perilymph and vitreous humour.

  • Nasal secretions can be tested for the presence of this protein and less than 1 ml of fluid is required for diagnosis.

  • False positive results are possible in patients with chronic liver disease, inborn errors of glycoprotein metabolism, genetic varients of transferrin, neuro psychiatric disease and rectal carcinoma . when these pathologic conditions are suspected sampling of venous blood should be sampled for comparison.


Beta trace protein is a another brain specific protein produced mainly in the leptomeninges and choroid. It is the second most abundant protein in CSF after albumin. It can also found in serum and perilymph . Beta trace protein is a reliable marker for detection of CSF in nasal secretions and it is used most commonly in Europe .


Glucose more than 30mg /dl or two thirds of blood glucose in clear nasal fluid indicates the presence of CSF in the nasal discharge.


Chloride concentration more than 110 mg/l suggests that the fluid is most likely CSF.

Role of imaging


Plain radiography are of limited value but they may show skull base fractures, fluid in the paranasal sinuses and intracranial air.


Plain CT brain is recommended in cases of spontaneous CSF leak to exclude causes such as intra cranial mass or hydrocephalus


HRCT provides thin sections (0.6-1mm) in both the axial and coronal planes. The axial images shows the posterior wall of frontal sinus and sphenoid sinuses. Coronal images shows the ethmoid complex, roof of sphenoid sinus and the tegmen of the middle ear. HRCT is able to identify even the smallest bone defect along with skull base with high sensibility. HRCT is independent on leak activity at the time of imaging.


In CTC 2,5,13 an intrathecal injection of non ionic contrast medium in the lumbar region.In the presence of active leak CTC demonstrates movement of the contrast through the defect.The rate of detection is lower if no leak is present at the time of investigation.The site of leakage is indicated by bony dehiscence, contrast agent in the adjacent para nasal sinuses,distortion of subarachnoid space and brain herniation.CTC is of particular use when the frontal and sphenoid sinuses act as reservoirs. CTC is contra indicated in patients with active meningitis and increased intracranial pressure.Weakness of this technique includes its inability to detect an active leak at the time of study,adverse reactions, and increase exposure to radiation.Contrast agents such as iohexol and iopamidol have a lower incidence of side effects.


MRC is a non invasive technique that can detect CSF fistula in multiple planes which does not involve the use of contrast (or) spinal puncture. On the T2 weighted fast spin echo the CSF has a characteristic bright signal that can generally distinguished from inflammatory paranasal sinus secretions. MRC is consider positive if herniation of brain tissue or arachnoids through a bony defect and CSF signal in the paranasal sinuses continues with CSF in the sub – arachnoid space. MRC is superior to CTC in cases of

  • Mutiple dural defects

  • Intermittent leakage

  • Dural defect <1mm


RNC is similar to CTC in that the radio active material most commonly TE-99 is injected intrathecally followed by gamma camera imaging in different positions. RNC is particularly useful in low volume or intermittent leaks.In such cases RNC is combained with endoscopic placement of nasal pledgets that are placed in sphenoethmoid recess ,middle meatus and olfactory cleft before starting the study.After imaging the blood samples are taken and the pledgets are removed at the same time,the normal ratio (radionuclide count in pledgets / radioneuclide count in blood sample) should be < 0.37, the pledget with highest count is assumed to have been nearest to the leak


This technique is highly successful and accurate in diagnosing and localising an active CSF leak most commonly used as an adjacent to intraoperative localization of a skull base defect .10ml of CSF is withdrawn by lumbar puncture is mixed with 0.2 to 0.5ml of 0.5% fluorescein and slowly injected through a lumbar drain. Fluorescein stained CSF can be seen as bright yellow or green. Use of a blue light filter makes the test sensitive upto 1 in 10 million.Side effects of this technique includes lower extremity weakness, numbness , generalized seizures, opisthotonus and cranial nerve deficits.


PET scan has been used to demonstrate a leak in some difficult cases where the side and site of the fistula is not obvious. This is particularly useful in cases of CSF otorrhoea where it is not clear whether the leak is from posterior fossa or middle cranial fossa.


Conservative Management6,7,9,10

Most CSF leaks resulting from accidental and surgical trauma heal with conservative measures over a period of 7-10 days . Conservative management consists of

  • Bed rest with head end elevation

  • Avoidence of straining activities such as nose blowing, sneezing and coughing

  • Use of laxatives and stool softeners to reduce straining

If the leak does not resolve within 3 days intermittent or continuous drainage of CSF may be tried for the next 4 days with removal of 150ml/day. Continuous CSF drainage is hazardous and should be used in caution . Over drainage can lead to intracranial aeroceles, severe brain displacement and coma. Intermittent drainage of 20-30ml over and 8 hour period into a closed system is safer.

A non-traumatic high pressure leaks caused by increased intracranial pressure will probably resolve if the intracranial pressure is normalized. Intra cranial pressure can be normalized by use of diuretics such as azetazolamide or with ventriculo peritoneal shunting. Leaks that do not resolve with normalization of intracranial pressure need surgical management. Normal pressure non traumatic leaks rarely close with conservative therapy and almost always require surgical exploration.

Antibiotic prophylaxis remains contraversial . Untreated CSF rhinorrhoea has been associated with a 25% risk of meningitis. Risk of meningitis is greater with

  • Delayed CSF leakage

  • Longer duration of CSF leakage

  • Concurrent infection

The arguments against antibiotic prophylaxis are

  • The antibiotics commonly used penetrate CSF poorly. If the antibiotics are used a combination of cotrimazole which is bactericidal in CSF and amoxicillin or penicillin which are bactericidal in nasal mucosa is recommended.

  • Antibiotics may promote resistant strains of organisms within the nasopharynx and consequently lead to infection with resistant or unusual organisms.

Surgical Management

The surgical management of CSF Rhinorrhoea can be divided into intracranial and extra cranial approaches. Dandy7 described the first surgical repair through a bifrontal craniotomy in 1929 . Dohlman 7 was the first to document the first intracranial repair of CSF leak in 1948 .In 1981 Wigand 7 described closure of CSF leak using an endoscopic approach . Majority of traumatic CSF fistulas heal without surgical intervention. Patients who develop CSF rhinorrhoea, shortly after trauma do not need surgery to close the CSF fistula.

Indications for early surgery are

  • Penetrating injury including gunshot wounds

  • Anterior cranial fossa surgery indicated for other reasons such as intracranial hematoma or to repair compound facial fractures with accessible dural tears being treated at the same time.

  • Meningitis once treated

  • A large intracerebral aerocele

  • Herniation of brain tissue through the nose

  • Radiological appearances that indicate a low probability of natural dural repair.

Delayed surgery is indicated for

  • Failed conservative management – CSF leak persisting beyond 10 days

  • Recurrent or delayed CSF leak after 10 days

  • Recurrent aerocele after 10 days

  • Meningitis or abscess at any time after surgery.

When CSF rhinorrhoea results from surgery the dural injury should be repaired when it occurs. Post operative leaks will usually close with conservative management.

Intra cranial repair2,3of CSF leak

Repair of anterior fossa fistulas can be approached by frontal anterior fossa craniotomy .Middle cranial fossa leaks from a petrous fracture is rare they are best approached through a subtemporal craniotomyPosterior fossa leaks from the posterior petrous surface are often associated with hearing loss. If the hearing is lost these fistulas may be repaired through a Trans labyrinthine approach. If the hearing is intact, they should be approached via the posterior fossa.Leaks from the sphenoid sinus area are difficult to approach via the intracranial route.

Intra cranial surgery is indicated when

  • operating for associated craniofacial injuries

  • Large bone defects that may be difficult to repair endoscopically.

  • The fistula site cannot be identified by endoscopic examination.

  • Tumours with intracranial extension that are not amenable to endoscopic resection

Advantages of intracranial repair are

  • Improved exposure

  • Ability to identify multiple defects

  • Repair can also be done even under condition of increased intra cranial tension

Disadvantages of intra cranial repair are

  • Increased morbidity

  • Permanent anosmia

  • Trauma related to brain retraction

  • Increased hospital stay

Extra cranial repair of CSF leak

Extra cranial approach includes anterior osteoplastic approach via bicoronal or eyebrow incision, external ethmodiectomy, transethmodial sphenoidectomy and transseptal sphenoidectomy have lower morbidity rates, higher success rates and no anosmia .They provide that best exposure of the sphenoid, parasellar and posterior ethmoids, cribriform plate, fovea ethmoidalis and fistuals in the posterior wall of frontal sinuses . Cerebral damage and the lateral extensions of the frontal and sphenoid sinuses cannot be assessed.


  • Facial scar

  • Facial numbness

  • Orbital complications

Endoscopic repair of CSF leak6.7,12,14

Endoscopic approach to CSF fistula depends on the suspected site of the lesion.presence of intra-cranial lesions,comminuted fractures of the cranial base , fracture of posterior wall of frontal sinus are contraindications for endoscopic repair. Patients who have an active CSF tear during surgery will not requires placement of fluorescein intrathecally . Fluorescein can help identify the site of smallleak that is intermittent or that has recently stopped leaking ,if blue-light filter is used on the light source even the smallest quantities of fluorescein can be visualised. ww

CSF leaks at the ethmoid sinus or the lateral lamella of cribriform plate will require complete endoscopic anterior and posterior ethmoidectomy to gain wide exposure to skull base . CSF leaks at the cribriform plate approached directly through olfactory groove. Sphenoid sinus CSF tears can be approached in many ways including a trans – septo sphenoid approach, approach through the spheno - ethmoid recess or a transethmoid approach. Defects located in the lateral recess of sphenoid sinus are difficult to access by the transeptal or transethmoid approaches and may requires an endoscopic transpterygoid approach . Defects directly involve the frontal recess may require a combained approach using endoscopic and open techniques because the superior extent of the defect may be difficult to reach endoscopically and inferior posterior extension may be difficult to reach from an external approach .Once the tear is localised, the nasal or sinus mucosa around the site of the tear is removed for about 5mm to expose the bone around the defect this allows attachment of the free graft to the bone . Sinus mucosa continues to secrete mucus and may seperate the graft from the recipient bed if the mucosa is not removed . when the appropriate mucosa is removed a diamond burr or curette can be used to abarade the recipient bed bone lightly and stimulate osteogenesis . If the dural defect in smaller than the bony defect the dural defect is enlarged to the size of bony defect for the adequate support of graft material with the underlying bone.

Graft materials

Historically, non vascularised graft such as pericranium, temporalis fascia, facia lata , muscle ,fat, allograft or synthetie dura or surgical cellulose mesh were used . These graft carried high risk of necrosis , post operative CSF leaks and infection.Today dural closure in accomplished by auto graft such as temporalis fascia , fascia lata, abdominal fat , septal mucoperichondrium and turbinate bone . Lypolised cadaver dura and bovine pericardium are also be used. These grafts are further supported by local or free vascularised tissue .The fibrin sealant provides a temporary water tight closure and creates a additional barrier to CSF leak .

Applying the graft.

The graft is applied using various techniques.

Onlay technique7,14,16,17

The onlay technique is generally employed for defects located in the 

lamina cribrosa where the presence of olfactory nerve filaments make it difficult to dissect dura from the adjacent skull base. Cartilage or bony graft is placed on the extra cranial surface of the skull duraplasty is then completed with a second layer of free muco perichondrium. This technique can also be used in lateral wall of extensively pneumatised sphenoid sinus.

Underlay technique7, 14 ,16 ,17

This is ideal for defects located in the fovea ethmoidalis. Graft material is positioned between the dura and the bone.

Bath pluq technique 8 ,7,2

Once the defect has been prepared the skull base defect is measured. If the size of the defect is measured if the size of the defect is less then 12mm a fat plug is harvested from the ear lobe.If the defect is larger than 12mm, fat is obtained either from the region of the greater trochanter of the thigh or from the abdomen. The fat of the ear lobe is preferred because the fat globules are tightly bound and easy to work with.The fat plug should be the same diameter as the defect and 1.5 to 2cm longA free mucosal graft is harvested from the lateral nasal wall (usually on the opposite side of CSF leak)

A 4 - 0 vicryl is knotted through the one end of the fat and the suture passed down the length of fat plug.The fat pluq is placed below the defect and a malleable frontal sinus probe in used to introduce the fat plug through the defect , once the fat plug has been safely introduced the plug is stabilised with the probe 

and the suture is gently pulled. The free mucosal graft is slide up the vicryl suture to cover the slightly protruding fat pluq and skull base defect.

Cuff – link repair 7

This technique uses a double layer of lyophilised dura or fascia to sandwich the dural defect, taking advantage of the hydrostatic CSF pressure to seal the defect and stop the leak. This is a variation of bath plug technique to repair sellar and clival defects successfully.

Sandwich Technique6,18

In sandwich technique the first layer of graft is inserted as an underlay, fibrin glue is then applied followed by a disc of septal cartilage designed to fit the bony defect this is followed by fibrin glue, the final layer of graft placed as overlay and the repair is supported with a vascularised graft.

Obliteration [ Tobacco pouch ] technique14 ,16,18

This is an alternative procedure for defects located in the lateral recess of sphenoid sinus. Placement of graft is not possible in these cases because of the adjacent neuro vascular structures . After careful removal of the entire mucosa investing the sinus, the entire cavity is obliterated with fascia lata plus gel foam or abdominal fat and then sealed by mucoperichondral graft.


1. Chang Yong,MD,Douglas D.Backous, MD ,FACS, Basic Principals of cerebrospinal fluid metabolism and intra cranial pressure homeostasis – Otolaryngologic Clinics of North America 38 ; 2005 569- 576
2. Peter L.Reilly , J. Wormold ,Lawrence F Marshall – Traumatic cerebrospinal fluid fistulas – Youman’s Neurologic Surgery 6 th Edition –Chapter 341 (3501 – 3515 )
3. Peter Reilly , Suren Krishnan Cerebrro Spinal Fistula – Operative Neuro surgery Vol -1 Chapter 22 (265 – 275 )
4. Robert Maroidi , Piero Nicolai , Antonino Robert Antonelli – Imaging and treatment planning for sino nasal diseases – 2005 Chapter – 7 (93 - 105 )
5. Fahad B Albadr , Ibraham A Alorainy – Radiological Management of Cerebrospinal Rhinorrhoea - Neurosciences 2004 ; Vol 9 (3 ); 158- 164
6. Rodney J Schlosser, MD William E. Bolger MD , FACS - Endoscopic Management of Cerebrospinal Fluid Rhinorrhoea ; Otolaryngologic clinics of North America 39 ; 2006 ; 523 – 538
7. Julie T. Kerr , MD , Felix W .K . Chu W . Bayles , MD ; MD, Stephen Cerebro spinal Fluid Rhinorrhoa diagnosis and Management ; Otolaryngologic Clinics Of North America 38 ; 2005 ; 597- 611
8. Peter - John Wormald Endoscopic Sinus Surgery Anatomy three Dimentional Reconstruction and Surgical Technique – 2 nd Edition Chapter 12 ; 154 - 165
9. Andrew H Marshall , Nicholas H Jones ; Scott - Brown’ S Otolaryngology , Head and Neck Surgery 7 th edition Cerebrospinal Fluid Rhinorrhoea ; 1636 – 1645
10. Martin J Citardi Samir Fakri Cummings Otolaryngology - Head and Neck Surgery - 5 th edition ; Vol – 1 ; Chapter 54
11. H . Reiber , K . Walther , H . Althaus ; Bata trace Protein as sensitive marker for csf Rhinorrhoea and Csf Otorrhoea Acta Neurol Scand 2003 ; 108 ; 359 – 362
12. Mostafa Zein Elabedin Ali ; Endoscopic Repair Of CSF Rhinorrhoea E.J.N.S Vol . 21 No . 2 ;2006 ; 49 -55
13. Prashant G Shetty , Manu M Shroff Dushyant V . Sahani Milind V. Kirtene ; Evaluation Of High Resolution CT And MR Cisternography In the Diagnosis Of CSF Fistula ; American Journal Of Neuro Radiology 19 ; 633 – 639 April 1998
14. Fuat Tosun , MD ; Ricardo L . Carrau MD; Carl H .Snyderman , MD; Amin Kassam Md ;Endonasal Endoscopic Repair Of Cerebrospinal Fluid Leaks Of The Sphenoid Sinus ; Arch Otolaryngol Head And Neck Surgery 2003 ; 129 ; 576 -580-
15. Mark K . Wax MD, Hassan H , Ramadan MD, Orlando Ortiz MD Stepen J . Wetmore MD; Contemporary Management Of Cerebrospinal Fluid Rhinorrhoea Otolaryngol Head And Neck Surgery ; 1997 ; 116 ; 442 - 449
16. Hasan . M Hezazy MD , Ricardo L Carrau Trans Nasal Endoscopic Repair Of Cerebrospinal Fluid Rhinorrhoea ; A Meta Analysis Laryngoscope ; Vol 110 , Issue 7 ; 1166 -1172 .
17. Hanna Gilat MD , Zvi Rappaport MD Andeitan Yaniv MD Endoscopic Transnasal cerebrospinal fluid leak repair a 10 year experience IMAJ – vol 13 –october 2011
18. W. Draf B. Schick - How I do it –Endoscopic – Microscopic Anterior skull base resection skull base 2007 january ; 17[1];53-58

Source(s) of Funding

This article did not receive any funding

Competing Interests

Authors dont have anything to declare in this front.


This article has been downloaded from WebmedCentral. With our unique author driven post publication peer review, contents posted on this web portal do not undergo any prepublication peer or editorial review. It is completely the responsibility of the authors to ensure not only scientific and ethical standards of the manuscript but also its grammatical accuracy. Authors must ensure that they obtain all the necessary permissions before submitting any information that requires obtaining a consent or approval from a third party. Authors should also ensure not to submit any information which they do not have the copyright of or of which they have transferred the copyrights to a third party.
Contents on WebmedCentral are purely for biomedical researchers and scientists. They are not meant to cater to the needs of an individual patient. The web portal or any content(s) therein is neither designed to support, nor replace, the relationship that exists between a patient/site visitor and his/her physician. Your use of the WebmedCentral site and its contents is entirely at your own risk. We do not take any responsibility for any harm that you may suffer or inflict on a third person by following the contents of this website.

1 review posted so far

1 comment posted so far

Excellent article Posted by Mr. Sridhar Rao on 26 Mar 2013 10:18:31 AM GMT

Please use this functionality to flag objectionable, inappropriate, inaccurate, and offensive content to WebmedCentral Team and the authors.


Author Comments
0 comments posted so far


What is article Popularity?

Article popularity is calculated by considering the scores: age of the article
Popularity = (P - 1) / (T + 2)^1.5
P : points is the sum of individual scores, which includes article Views, Downloads, Reviews, Comments and their weightage

Scores   Weightage
Views Points X 1
Download Points X 2
Comment Points X 5
Review Points X 10
Points= sum(Views Points + Download Points + Comment Points + Review Points)
T : time since submission in hours.
P is subtracted by 1 to negate submitter's vote.
Age factor is (time since submission in hours plus two) to the power of 1.5.factor.

How Article Quality Works?

For each article Authors/Readers, Reviewers and WMC Editors can review/rate the articles. These ratings are used to determine Feedback Scores.

In most cases, article receive ratings in the range of 0 to 10. We calculate average of all the ratings and consider it as article quality.

Quality=Average(Authors/Readers Ratings + Reviewers Ratings + WMC Editor Ratings)