Endoscopic cerebrospinal fluid rhinorrhea repair: Is a lumbar drain necessary?

OBJECTIVES: To determine the necessity for lumbar drains during endoscopic cerebrospinal fluid (CSF) rhinorrhea repair. METHODS: Thirty-three patients underwent endoscopic repair of CSF rhinorrhea without a lumbar drain during a 7-year period. The size of the dural defect ranged from a microleak (less than 1 mm dural defect) to a 3-cm dural defect of the anterior skull base. RESULTS: All of the procedures in patients with smaller defects (<5 mm) were performed on an outpatient basis. Thirty-two patients (97%) had complete resolution of their CSF leak after 1 procedure without any recurrence (average follow-up 29 months). CONCLUSION: A lumbar drain is not routinely necessary for successful closure of CSF rhinorrhea of any size. Smaller dural defects may be safely performed on an outpatient basis without complications.     

Subcranial transnasal repair of cerebrospinal fluid rhinorrhea with free autologous grafts by the combined overlay and underlay techniques.

OBJECTIVE: To determine the efficacy of subcranial transnasal repair of cerebrospinal fluid rhinorrhea with free autologous grafts by the combined overlay and underlay techniques using the surgical microscope and/or endoscope. PATIENTS AND METHODS: Twenty patients with CSF rhinorrhea were included in this retrospective study. They were 13 males and 7 females. Their age ranged from 7 to 62 years (mean: 39.35). The etiologies of the leak were iatrogenic in 10 cases, spontaneous in 5 cases, traumatic in 4 cases and one case was associated with meningeo-encephalocele. Preoperative nasal endoscopic examination, computed tomography (CT) with intrathecal non-ionic contrast and magnetic resonance imaging (MRI) were done when indicated. Endoscopic and/or microscopic repair of the CSF fistula was done by a combination of both underlay and overlay repair with free autologous grafts as follows: Gelfoam with fibrin glue, strips of fat, facia lata, Gelfoam with fibrin glue (underlay), septal cartilage, Gelfoam with fibrin glue and strips of fat (overlay). RESULTS: Complete closure of the leak was achieved in all patients. In one case of spontaneous CSF leak which was operated endoscopically, the leak recurred 6 months postoperatively and ceased spontaneously after a month with conservative medical treatment. No major complications were seen and no patients developed meningitis or postoperative anosmia. CONCLUSION: Subcranial transnasal repair with free autologous grafts by the combined overlay and underlay techniques using the endoscope or surgical microscope is a safe and successful method of treating CSF leaks, provided that the CSF leak is precisely located and the site can be reached with the endoscope or surgical microscope.     

Endonasal Endoscopic Closure of Cerebrospinal Fluid Rhinorrhea

The authors review their experience with endoscopic repair of skull base defects associated with cerebrospinal fluid (CSF) rhinorrhea involving the paranasal sinuses. A total of 22 patients was treated endoscopically between 1992 and 1998. The repair method consisted of closure of the CSF fistula with a free autologous abdominal fat graft and fibrin glue, supported with a sheet of silastic. The primary closure rate was 82% (18/22), and the overall closure rate was 95.5% (21/22) without recurrence or complications within an average follow-up of 5 years (14-83 months). A single patient still complains of cerebrospinal rhinorrhea, although this was never proved by any clinical, endoscopic, or biological (β₂-transferrin) examination. The repair of ethmoidal-sphenoidal cerebrospinal fluid fistulae by endonasal endoscopic surgery is an excellent technique, both safe and effective. Fat is a material of choice, as it is tight and resists infection well. The technique and indications for endoscopic management of cerebrospinal fluid leaks are discussed.     

Analysis of different surgical approaches for the treatment of cerebrospinal fluid rhinorrhea.

The current treatment method for cerebrospinal fluid (CSF) rhinorrhea is surgical repair of the fistula. The aim of this study was to analyse different surgical approaches used for the treatment of CSF rhinorrhea regarding several preoperative and postoperative variables to determine the optimal method in these patients. Patients' charts were retrospectively reviewed to get the required data. Twenty-six patients who underwent different types of surgical approach for the treatment of CSF rhinorrhea were included in the study. Patients who had extensive comminuted fractures of the anterior cranial base and additional brain injury besides CSF rhinorrhea, mostly as a result of gunshot injuries, underwent craniotomy (n = 14). Osteoplastic frontal sinusotomy was used in two patients with a dural defect located at the posterior wall of the frontal sinus. Uncomplicated CSF fistulas in ten patients, located at the anterior and posterior ethmoid roof and in the sphenoid sinus, were closed with an endonasal endoscopic approach. Postoperative success rate was higher (97 % for intracranial approach, 100 % for extracranial external and endonasal endoscopic approach) for all techniques. Anosmia was the most frequent permanent complication (n = 5), seen after craniotomy. In conclusion, endonasal endoscopic approach can be preferred for the closure of uncomplicated CSF fistula, located at the anterior or posterior ethmoid roof and in the sphenoid sinus, due to its minimal postoperative morbidity. Uncomplicated CSF fistula, located at the posterior wall of frontal sinuses can be repaired extradurally with osteoplastic frontal sinusotomy. Intracranial approaches should be reserved for more complicated CSF rhinorrhea which results from extensive comminuted fractures of the anterior cranial base and is accompanied with intracranial complications.     

Minimally Invasive Technique for Repairing CSF Leaks Due to Defects of Posterior Table of Frontal Sinus

Objective Cerebrospinal fluid (CSF) leaks from the frontoethmoid and sphenoid region can be easily dealt with endoscopic approaches, but CSF rhinorrhea due to frontal sinus fractures are difficult to treat solely by the nasal endoscopic approach and may require external repair. The technique described targets defects of the posterior table of the frontal sinus where conventional osteoplastic approach of obliteration is usually done. This technique is minimally invasive and involves repair using an endoscope via a frontal trephine. Methods We have treated five cases of traumatic CSF rhinorrhea with this technique, and the mean follow-up is 1 year (range: 10–14 months). The frontal sinus is opened by making a small stab incision (frontal trephine), and the defect site is localized by visualization via endoscope through the trephine. The repair is then performed with fat, bone graft, and fibrin glue. Results Closure of the defect was achieved in a single stage in all the patients, and none of them had a recurrence of leak in the 1-year follow-up period. Conclusion This is a good technique for superiorly and laterally placed posterior table defects of the frontal sinus with minimal morbidity and excellent closure rates.     

鼻内窥镜下修补脑脊液鼻漏

目的探讨经鼻内窥镜修补脑脊液鼻漏的方法和疗效。方法于2004年5月～10月间应用鼻内窥镜处理脑脊液鼻漏3例：寻找到瘘孔后，利用肌浆填补法修补瘘孔，其中采用Messerklinger入路处理额窦、筛顶鼻漏各1例，Wigand入路处理蝶窦鼻漏1例。结果全部病例均一次手术修补成功，随访半年无复发。结论在鼻内窥镜下寻找瘘孔，利用肌肉组织和筋膜修补脑脊液鼻漏可取得较好的疗效。     

Treatment of traumatic cerebrospinal fluid rhinorrhea via extended extradural anterior skull base approach

Objective: To describe and assess the repair technique and perioperative management for cerebrospinal fluid (CSF) leak resulting from extensive anterior skull base fracture via extradural anterior skull base approach. Methods: This was a retrospective review conducted at the Department of Neurosurgery of the Shanghai Tenth People''s Hospital from January 2015 to April 2020. Patients with traumatic CSF rhinorrhea resulting from extensive anterior skull base fracture treated surgically via extended extradural anterior skull base approach were included in this study. The data of medical and radiological records, surgical approaches, repair techniques, peritoperative management, surgical outcome and postoperative followup were analyzed. Surgical repair techniques were tailored to the condition of associated injuries of the scalp, bony and dura injuries and associated intracranial lesions. Patients were followed up for the outcome of CSF leak and surgical complications. Data were presented as frequency and percent. Results: Thirty-five patients were included in this series. The patients’ mean age was 33 years (range 11-71 years). Eight patients were treated surgically within 2 weeks; while the other 27 patients, with prolonged or recurrent CSF rhinorrhea, received the repair surgery at 17 days to 10 years after the initial trauma. The mean overall length of follow-up was 23 months (range 3-65 months). All the patients suffered from frontobasal multiple fractures. The basic repair tenet was to achieve watertight seal of the dura. The frontal pericranial flap alone was used in 20 patients, combined with temporalis muscle and/or its facia in 10 patients. Free fascia lata graft was used instead in the rest 5 patients. No CSF leak was found in all the patients at discharge. There was no surgical mortality in this series. Bilateral anosmia was the most common complication. At follow-up, no recurrent CSF leak or meningitis occurred. No patients developed mucoceles, epidural abscess or osteomyelitis. One patient ultimately required ventriculoperitoneal shunt because of progressive hydrocephalus. Conclusion: Traumatic CSF rhinorrhea associated with extensive anterior skull base fractures often requires aggressive treatment via extended intracranial extradural approach. Vascularized tissue flaps are ideal grafts for cranial base reconstruction, either alone or in combination with temporalis muscle and its fascia—fascia lata sometimes can be opted as free autologous graft. The approach is usually reserved for patients with traumatic CSF rhinorrhea in complex frontobasal injuries.     

Endoscopic endonasal approach for cerebrospinal fluid fistulae.

Different techniques have been proposed to repair cerebrospinal fluid rhinorrhea. Advances in nasal surgery led to a high success rate and low morbidity for the endonasal approach. It has become the favorite route for treating cerebrospinal fluid leaks of the anterior skull base. Better results have been obtained with the improvement of rigid endoscopes and intrathecal sodium fluorescein. In a prospective study, twenty-four patients with cerebrospinal fluid rhinorrhea were evaluated and treated by endoscopic endonasal surgery. In all cases intrathecal sodium fluorescein enabled a precise localization of the bone defect. The most common causes of CSF rhinorrhea were traumatic (8 cases, 33 %), spontaneous (6 cases, 25 %), and iatrogenic (5 cases, 20.8 %). Preoperative radiological evaluations (plane CT, CT cisternogram and MRI) showed the exact site and size of the defect in all patients. The most common site of leakage was the ethmoidal roof-cribriform plate. Primary closure was achieved in all patients. There were no major operative or postoperative complications. The endoscopic endonasal approach can be considered the first choice in the treatment of cerebrospinal fluid rhinorrhea.     

The Efficacy of Computer Assisted Surgery in the Endoscopic Management of Cerebrospinal Fluid Rhinorrhea

OBJECTIVE: To determine the outcome of endoscopic repair of cerebrospinal fluid (CSF) rhinorrhea with and without computer assisted surgery. STUDY DESIGN: A review of all patients undergoing endoscopic closure of CSF rhinorrhea at a tertiary care medical center between 1994 and 2003. Charts from the 24 patients were reviewed for indications, location of leak, type of surgical closure, number of prior closure attempts, graft materials, use of computer assisted surgery, complications, and need for revision surgery. Analysis was performed to determine a possible correlation between success of CSF leak repair and use of computer assisted surgery. RESULTS: The etiology of the leak was previous sinus surgery in 10 patients (41.7%), trauma in 5 patients (20.8%), spontaneous leak in 5 patients (20.8%), and skull base surgery in 4 patients (16.7%). The most common sites of leak were the fovea ethmoidalis in 10 patients (41.7%), cribriform plate in 8 patients (33.3%), and sphenoid sinus in 6 patients (25%). Image guidance was employed in 66.7% (16 patients) of our first attempted repairs. Six patients underwent a total of 9 revision procedures. At last follow-up, 96% of patients had no evidence of CSF rhinorrhea. A comparison of patients in the 2 groups failed to reveal a statistically significant difference in the rate of CSF leak closure. CONCLUSION: Endoscopic closure of CSF rhinorrhea represents a minimally invasive and highly successful procedure. The use of computer assistance may improve the confidence of the surgeon and is a valuable adjunct in this procedure. Our study, however, did not demonstrate an improvement in the rates of successful closure with the use of computer assistance.     

Endoscopic treatment of traumatic basal encephaloceles: a report of 8 cases

OBJECT: Basal encephaloceles are rare entities that can present as congenital diseases; however, traumatic lesions due to head injuries or iatrogenic causes have been described in the literature. In this study the authors aimed to define placement techniques for free grafts in repairing traumatic basal encephaloceles and to describe the long-term effectiveness of endoscopic treatment. METHODS: Between September 1997 and December 2006, 8 patients with traumatic encephaloceles underwent endoscopic surgery. A free graft following an underlay (2 cribriform plate and 4 ethmoid fovea defects) or obliteration (2 sphenoid defects) procedure was used as the repair material. RESULTS: All traumatic basal encephaloceles with the associated skull base defects and cerebrospinal fluid (CSF) leakage were successfully treated via the endoscopic approach. There were no major complications or recurrence of meningitis or leakage of CSF encountered after an average follow-up of 77 months. CONCLUSIONS: Long-term follow-up results demonstrated that endoscopic surgery was suitable for the treatment of traumatic basal encephaloceles. The underlay procedure is more appropriate than the overlay procedure in repairing large defects of the anterior skull base. Meticulous manipulations of the endoscope following precise autograft placement are mandatory for the successful repair of traumatic basal encephaloceles.     

Endoscopic Endonasal Repair of Cerebrospinal Fluid Leakage Caused by a Rare Traumatic Clival Fracture

An 89-year-old male presented with cerebrospinal fluid (CSF) rhinorrhea associated with head trauma sustained as a pedestrian in a traffic accident. Computed tomography (CT) showed pneumocephalus and multiple cranial bone fractures, including the clivus. Although the CSF rhinorrhea was treated conservatively for a week, clinical symptoms did not improve and surgical repair was performed. Preoperative thin-sliced bone CT and steady-state magnetic resonance images revealed a bone defect at the middle clivus and a collection of CSF fluid from the clival fistula in the sphenoid sinus. Endoscopic endonasal reconstruction was performed, and the 3-mm diameter dural tear and bone defect at the middle clivus were well visualized. The fistula was repaired using a pedicled nasoseptal mucosal flap. The CSF rhinorrhea completely disappeared as a result of the endoscopic endonasal surgery. The present report describes a rare case of CSF rhinorrhea caused by a traumatic clival fracture and surgical management by endoscopic endonasal surgery.     

Extracranial repair of cerebrospinal fluid fistulas: technique and results in 37 patients

Although neurosurgeons have traditionally preferred intracranial repair for the management of cerebrospinal fluid (CSF) fistulas, this approach is associated with the complications of a craniotomy, anosmia, and a high incidence of recurrent fistulas. Extracranial repair, on the other hand, produces no central nervous system morbidity, preserves olfaction, and is associated with a low incidence of recurrence. Although there have been several reports of extracranial repair of CSF fistulas by otorhinolaryngologists, this approach has received scant mention in the neurosurgical literature. We report here our experience with 37 patients with CSF rhinorrhea or otorrhea who underwent extracranial repair. The etiology of the fistula was postoperative in 22, traumatic in 6, and spontaneous in 9. The fistulas were repaired using one of four techniques: external ethmoid-sphenoid in 18 patients, transmastoid in 9, transseptosphenoid in 7, and osteoplastic frontal sinusotomy in 3. In 32 of the 37 patients (86%) the fistulas were successfully repaired with the initial procedure. Of the 5 patients requiring a second operation, the fistula was successfully closed in 4 for an overall success rate of 97%. Complications were few and consisted of a transient facial paresis in a patient undergoing transmastoid repair and one death from meningitis. The authors conclude that because of low morbidity and mortality and a high success rate in closing fistulas, extracranial repair is the preferred technique for the operative management of CSF rhinorrhea and otorrhea.     

Combined Transcranial-endonasal Reconstructive Surgery for Cerebrospinal Fluid Leakage Resulting from Traumatic Anterior Skull Base Fractures Involving the Parasellar Region

Extensive traumatic anterior skull base fractures from the frontal sinus to the parasellar region are frequently accompanied by multiple dural defects that cause persistent cerebrospinal fluid (CSF) leakage. Conventional transcranial reconstruction using a frontal periosteal flap is frequently insufficient, and parasellar dural defects are often deep, complex, and difficult to identify. In this report, we describe a combined transcranial–endonasal reconstructive technique and report our experience. Simultaneous combined transcranial and endoscopic surgery was performed in three patients with CSF leakage resulting from traumatic anterior skull base fractures. Dural defects were thoroughly identified from the transcranial and endonasal surgical fields, and covered using a multilayer sealing technique. The anterior regions of the anterior skull base were reconstructed using a free fascial flap and frontal periosteal flap; posterior and parasellar regions were reconstructed using a fat graft, vascularized nasoseptal flap, and endonasal balloon. Suturing the transcranial grafts to the parasellar dura mater was performed collaboratively by the transcranial and endonasal surgeons. In our cases, complete cessation of CSF leakage was achieved without perioperative lumbar drainage in all patients. Mean time to postoperative ambulation was 7 days (range, 3–11). No surgical complications occurred. Simultaneous transcranial and endonasal procedures were helpful to detect all sites of CSF leakage and secure reconstructive grafts. The combined transcranial and endonasal reconstructive technique achieved secure skull base reconstruction without recurrence of CSF leakage, and allowed early postoperative ambulation. This technique can be a reliable surgical option to repair CSF leakage resulting from extensive anterior skull base fractures.     

Primary closure of a cerebrospinal fluid fistula by nonpenetrating titanium clips in endoscopic endonasal transsphenoidal surgery: technical note

Postoperative cerebrospinal fluid (CSF) leakage is one of the most common and aggravating complications in transsphenoidal surgery. Although primary closure of the fistula would be the most desirable solution for an intraoperatively encountered CSF leak, it is difficult to achieve in such a deep and narrow operative field. In this article, the authors report endonasal endoscopic applications of no-penetrating titanium clips to repair a CSF fistula following tumor removal. The AnastoClip Vessel Closure System (VCS; LeMaitre Vascular, Boston, MA) was used for closure of a CSF fistula in endonasal transsphenoidal surgery. In all four patients, CSF leakage was successfully obliterated primarily with two to five clips. There was no postoperative CSF rhinorrhea or complications related to the use of the VCS. Metal artifact by the clips on postoperative images was tolerable. Primary closure of the fistula using the VCS was an effective strategy to prevent postoperative CSF leakage in transsphenoidal surgery. Future application can be expanded to reconstruction of the skull base dura via endonasal skull base approaches.     

Purely endoscopic repair of traumatic cerebrospinal fluid rhinorrhea from the anterior skull base: case report

A 38-year-old woman presented with a case of post-traumatic ethmoidal cerebrospinal fluid (CSF) leak that was repaired using a purely endoscopic endonasal approach. Six weeks after a mild domestic maxillofacial trauma, she started complaining of clear, watery discharge from the left nostril and headache. Neuroimaging investigations disclosed a linear fracture of the left anterior ethmoidal roof without evidence of large bony breaches or any brain tissue damage. After conservative medical treatment with carbonic anhydrase inhibitors failed, she was referred to our hospital for surgical repair of the osteodural defect. An endoscopic endonasal transethmoidal approach was successfully performed, and an overlay technique was used to reconstruct the defect. The patient was discharged without clinical evidence of CSF rhinorrhea and no leaks were apparent at the 3-month follow-up clinical and radiological examinations. Post-traumatic CSF rhinorrhea occurs in cases of dural tears associated with small bone breaks, most frequently involving the anterior skull base. Recovery is often spontaneous following only bed rest, or with medical treatments such as inhibitors of carbonic anhydrase diuretics, steroids, or eventually stool softeners to help reduce CSF pressure. Surgical repair is required when first-line conservative treatment proves ineffective. The present case shows that the endoscopic endonasal technique for the management of CSF leaks provides a less invasive surgical route to achieve valid dural repair.     

Management of sphenoid sinus cerebrospinal fluid rhinorrhea: making use of an extended approach to the sphenoid sinus.

OBJECTIVES: Specific information addressing the management of cerebrospinal fluid (CSF) fistulas that originate from within the sphenoid sinus remains scant. The objective of this study was to review the cause and management of CSF rhinorrhea arising from the sphenoid sinus. STUDY DESIGN AND SETTING: This is a retrospective chart review of 12 cases of CSF rhinorrhea arising from the sphenoid sinus that occurred in 11 patients. All patients were treated at a single institution between 1994 and 1999. RESULTS: All patients were managed surgically with sphenoid sinus fat obliteration using an endoscopic sublabial, transseptal approach. This approach was successful for all 12 cases, with median duration of follow-up of 18 months. CONCLUSIONS: Endoscopically assisted transseptal repair of CSF fistulas that originate within the sphenoid sinus offers an alternate approach to previously described methods of repair in this region. Advantages include wide access to the entire sphenoid sinus, improved access to laterally pneumatized regions within the sphenoid sinus, and rostral mucosal closure over the repair within the sinus.     

A Reconstruction Method Using Musculopericranial Flaps that Prevents Cerebrospinal Fluid Rhinorrhea and Intracranial Complications after Extended Anterior Skull Base Resection

Anterior skull base defects after extended anterior skull base resection including unilateral orbit and the dura were reconstructed using the temporal musculopericranial (TMP) flaps or frontal musculopericranial (FMP) flap in 14 patients. Dural defect was reconstructed with the TMP or FMP flap by making it overlap on the remaining dura around the defects. These flaps were also used, in principle, for the separation of the nasal cavity. For bone defects on the anterior skull base, a bone graft was transplanted in the place between the flap for dural reconstruction and the flap for the separation of the nasal cavity. Bone grafting was nor performed in patients who had an extensive defect and for whom a free flap was used for the separation. After surgery, CSF rhinorrhea did not occur in the 14 patients. Twelve patients did not develop any postoperative complications. Two patients had epidural abscess, but with debridement and the drainage to the nasal cavity, they did not develop severe intracranial complications. We conclude that reconstruction using musculopericranial flaps is a reliable and versatile method with minimum invasion and the shortest operation hours. In particular, musculopericranial flap for dura reconstruction was highly efficacious for the prevention of CSF rhinorrhea.     

Continuous cerebrospinal fluid drainage using a lumbar subarachnoid catheter for cerebrospinal fluid rhinorrhea after functional endoscopic sinus surgery

Anesthesiologists are frequently consulted for performing lumbar cerebrospinal fluid (CSF) drainage to facilitate surgery or manage complications. Functional endoscopic sinus surgery (FESS) is a common treatment for chronic sinus diseases. Cerebrospinal fluid (CSF) leakage is a serious complication following FESS and is typically treated with an endonasal free or rotational mucoperichondrial flap. Continuous drainage of CSF with a lumbar subarachnoid catheter has been used in patients who have undergone neurosurgery but it is seldom used in the treatment of post-FESS CSF rhinorrhea. We present a 71-year-old male patient who suffered from CSF rhinorrhea after FESS, and was treated successfully with continuous lumbar CSF drainage. We are of the opinion that continuous CSF drainage with a lumbar subarachnoid catheter is an effective and safe modality of treatment for post-FESS CSF leakage.     

A Reconstruction Method Using Musculopericranial Flaps that Prevents Cerebrospinal Fluid Rhinorrhea and Intracranial Complications after Extended Anterior Skull Base Resection

Anterior skull base defects after extended anterior skull base resection including unilateral orbit and the dura were reconstructed using the temporal musculopericranial (TMP) flaps or frontal musculopericranial (FMP) flap in 14 patients. Dural defect was reconstructed with the TMP or FMP flap by making it overlap on the remaining dura around the defects. These flaps were also used, in principle, for the separation of the nasal cavity. For bone defects on the anterior skull base, a bone graft was transplanted in the place between the flap for dural reconstruction and the flap for the separation of the nasal cavity. Bone grafting was nor performed in patients who had an extensive defect and for whom a free flap was used for the separation. After surgery, CSF rhinorrhea did not occur in the 14 patients. Twelve patients did not develop any postoperative complications. Two patients had epidural abscess, but with debridement and the drainage to the nasal cavity, they did not develop severe intracranial complications. We conclude that reconstruction using musculopericranial flaps is a reliable and versatile method with minimum invasion and the shortest operation hours. In particular, musculopericranial flap for dura reconstruction was highly efficacious for the prevention of CSF rhinorrhea.     

CSF rhinorrhoea: the place of endoscopic sinus surgery

Cerebrospinal fluid (CSF) rhinorrhoea has been managed by both neurosurgeons and otorhinolaryngologists, with neurosurgeons often choosing an intracranial approach and otorhinolaryngologists an extracranial approach. Recently, transnasal endoscopic techniques have been introduced that significantly reduce the morbidity of surgical repair when compared with previous techniques. The sense of smell was preserved in all patients who underwent an endoscopic repair of their CSF leak where it was present preoperatively. The results of transnasal endoscopic repair now make it the treatment of choice for most anterior cranial and sphenoid CSF leaks, with the exception of defects in posterior wall of the frontal sinus or defects larger than 5 cm. It is vital that a diagnosis of a CSF leak is confirmed by immunofixation of beta 2 transferrin as unilateral rhinorrhoea can masquerade as a CSF leak. We illustrate our experience with 78 patients who were referred with a diagnosis of CSF rhinorrhoea.