Endonasal endoscopic repair of anterior skull-base fistulas: the Kuala Lumpur experience

Diagnosis and Localization of Cerebrospinal Fluid Rhinorrhea: A Systematic Review

Background

Cerebrospinal fluid (CSF) rhinorrhea results from abnormal communications between the subarachnoid and sinonasal spaces. Accurate preoperative diagnosis and localization are vital for positive clinical outcomes. However, the diagnosis and localization of CSF rhinorrhea remain suboptimal due to a lack of accurate understanding of test characteristics.

Objective

This systematic review aims to assess the diagnostic accuracy of various tests and imaging modalities for diagnosing and localizing CSF rhinorrhea.

Methods

A systematic review of the MEDLINE and EMBASE databases was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Results

Our search identified 4039 articles—53 cohort studies and 24 case series describing 1622 patients were included. The studies were heterogeneous and had a wide range of sensitivities and specificities. Many specificities were incalculable due to a lack of true negative and false positive results, thus precluding a meta-analysis. Median sensitivities and specificities were calculated for cohort studies of the following investigations: high-resolution computed tomography (HRCT) 0.93/0.50 (sensitivity/specificity), magnetic resonance cisternography (MRC) 0.94/0.77, computed tomography cisternography (CTC) 0.95/1.00, radionuclide cisternography (RNC) 0.90/0.50, and contrast-enhanced magnetic resonance cisternography (CEMRC) 0.99/1.00, endoscopy 0.58/1.00, topical intranasal fluorescein (TIF) 1.00/incalculable, intrathecal fluorescein (ITF) 0.96/1.00. Case series were reviewed separately. Etiology and site-specific data were also analyzed.

Conclusion

MR cisternography is more accurate than high-resolution CT at diagnosing and localizing CSF rhinorrhea. CT cisternography, contrast-enhanced MR cisternography, and radionuclide cisternography have good diagnostic characteristics but are invasive. Intrathecal fluorescein shows promising data but has not been widely adopted for purely diagnostic use. Office endoscopy has limited data but does not sufficiently diagnose CSF rhinorrhea independently. These findings confirm with current guidelines and evidence.

Spontaneous nasal cerebrospinal fluid leaks: management of 24 patients over 11 years

PURPOSE

Most cases of non-traumatic nasal cerebrospinal fluid (CSF) leaks occur spontaneously without any obvious reason. Severe and life-threatening complications are possible consequences. Endoscopic repair is considered the gold standard; however, diagnosis and therapy of these CSF leaks stay challenging.

METHODS

In this retrospective analysis, patients who presented with spontaneous nasal CSF leaks from 2006 to 2017 were included. Symptoms, diagnostics, localization of the skull base defect, surgical method, outcome, and postoperative treatment were recorded.

RESULTS

Twenty four patients were included. 8 patients presented with symptoms of meningitis. The skull base defects were most commonly located in the anterior ethmoid roof-especially in the cribriform plate-and in the lateral part of the sphenoid sinus. 21 patients had a BMI above 25. In only 13 cases the defect could be detected preoperatively via computed tomography or additional magnetic resonance imaging. In all patients intraoperative visualization of the CSF leak was possible using intrathecal application of sodium-fluorescein. Endoscopic repair was the initial surgical method for all patients and proved to be successful in 80% of the cases. In most cases surgical revision was performed endoscopically; however, in two patients an open transpterygoidal approach was necessary.

CONCLUSIONS

Spontaneous nasal CSF leaks often initially present with symptomatic meningitis. Imaging does not always clearly identify the skull base defect. Common localizations are the anterior ethmoid roof and the lateral sphenoid sinus. Obesity seems to be a predisposing factor. In most cases, endoscopic repair with low morbidity is possible; however, an individualized approach is necessary.

A Systematic Review of Secondary Cerebrospinal Fluid Leaks

Background

Secondary cerebrospinal leaks (CSF) are leaks that recur after an initial endoscopic repair of CSF leaks. Identification of characteristics that could predict secondary leaks may allow surgeons to plan repairs with the knowledge that these defects are more likely to fail.

Objective

To identify characteristics that could predict secondary CSF leaks.

Methods

A search of all studies that reported outcomes after endoscopic repair of CSF leaks was conducted by using medical literature data bases. Studies with the following criteria were included: written in the English language, secondary CSF leaks after primary repair, and assessment of success of fistula repair. Data extracted included the etiology of the leak, site of the leak, reconstructive materials used, and success of the repair.

Results

Ninety-four studies, from 1988 to 2015, with a total of 3149 primary CSF leaks were included. Sixty-three studies (67%) had a success rate of ≥80%; 77 studies (82%) had secondary leak rates of <40%. For 88 of the 94 studies (94%), the success rate after secondary repair improved to 81.0–100%. Of 48 studies that included leaks of more than one site, the sphenoid was the most common site of leak in 26 studies (55%), the ethmoid was the most common site in 16 studies (34%), and the cribriform was the most common site in 11 studies (23%).

Conclusion

The rate of secondary CSF leaks was low due to advances in endoscopic repair techniques. Spontaneous and iatrogenic CSF leaks were more likely to recur, especially without adequate control of underlying factors, such as increased intracranial pressure and obesity. Further studies with consistent reporting are required for more definitive conclusions about secondary CSF leaks.

Intervention for elevated intracranial pressure improves success rate after repair of spontaneous cerebrospinal fluid leaks

OBJECTIVES/HYPOTHESIS

Spontaneous cerebrospinal fluid (CSF) leaks are associated with increased intracranial pressure (ICP) and considered a manifestation of idiopathic intracranial hypertension. Although postoperative acetazolamide and placement of CSF shunt systems are considered valuable interventions for elevated ICP, the impact on recurrence rate remains unclear. The objective of this study was to systematically review evidence from reported literature to evaluate whether postoperative ICP management reduces recurrence rates after primary endoscopic repair.

STUDY DESIGN

Prospective case series and systematic review.

METHODS

Demographics, defect location, success rates, and ICP management in spontaneous CSF leak patients were prospectively collected over 8 years. A search was also conducted in PubMed to identify studies reporting cases of spontaneous CSF rhinorrhea.

RESULTS

Fifty-six articles with nonduplicated data were identified and combined with a prospective series of 108 patients for a total of 679 patients treated for spontaneous CSF rhinorrhea. Average age was 50.4 years with 77% female. Average body mass index was 35.8 kg/m² . Defects were most commonly located in the sphenoid sinus (n = 334) followed by the ethmoid (n = 318) and the frontal sinus (n = 46). Successful primary repair was 92.82% in patient cohorts where ICP evaluation and intervention with acetazolamide or CSF shunt systems was performed, but was significantly decreased to 81.87% in series with no active management of elevated ICP (P < .001).

CONCLUSIONS

Evaluation and intervention for elevated ICP in spontaneous CSF leaks is associated with significantly improved success rates following primary endoscopic repair.

LEVEL OF EVIDENCE

4. Laryngoscope, 127:2011-2016, 2017.

Endoscopic management of cerebrospinal fluid rhinorrhea

Cerebrospinal fluid (CSF) rhinorrhea occurs due to communication between the intracranial subarachnoid space and the sinonasal mucosa. It could be due to trauma, raised intracranial pressure (ICP), tumors, erosive diseases, and congenital skull defects. Some leaks could be spontaneous without any specific etiology. The potential leak sites include the cribriform plate, ethmoid, sphenoid, and frontal sinus. Glucose estimation, although non-specific, is the most popular and readily available method of diagnosis. Glucose concentration of > 30 mg/dl without any blood contamination strongly suggests presence and the absence of glucose rules out CSF in the fluid. Beta-2 transferrin test confirms the diagnosis. High-resolution computed tomography and magnetic resonance cisternography are complementary to each other and are the investigation of choice. Surgical intervention is indicated, when conservative management fails to prevent risk of meningitis. Endoscopic closure has revolutionized the management of CSF rhinorrhea due to its less morbidity and better closure rate. It is usually best suited for small defects in cribriform plate, sphenoid, and ethmoid sinus. Large defects can be repaired when sufficient experience is acquired. Most frontal sinus leaks, although difficult, can be successfully closed by modified Lothrop procedure. Factors associated with increased recurrences are middle age, obese female, raised ICP, diabetes mellitus, lateral sphenoid leaks, superior and lateral extension in frontal sinus, multiple leaks, and extensive skull base defects. Appropriate treatment for raised ICP, in addition to proper repair, should be done to prevent recurrence. Long follow-up is required before leveling successful repair as recurrences may occur very late.

Endoscopic Endonasal Anterior Skull Base Surgery: A Systematic Review of Complications During the Past 65 Years

BACKGROUND

Endoscopic skull base surgery is becoming more popular as an approach to the anterior skull base for tumors and cerebrospinal fluid (CSF) fistulae. It offers the advantages of better cosmesis and improved quality of life after surgery. We reviewed the complication rates reported in the literature.

METHODS

A literature search was performed in the electronic database Ovid MEDLINE (1950 to August 25, 2015) with the search item "([Anterior] AND Skull base surgery) AND endoscopic."

RESULTS

We identified 82 relevant studies that included 7460 cases. An average overall complication rate of 17.1% (range 0%-68.0%) and a mortality rate of 0.4% (0%-10.0%) were demonstrated in a total of 82 studies that included 7460 cases. The average CSF leak rate for all studies was 8.9% (0%-40.0%) with meningiomas and clival lesions having the greatest CSF leak rates. The most frequent benign pathology encountered was pituitary adenomas (n = 3720, 49.8% of all cases) and the most frequent malignant tumor was esthesioneuroblastoma (n = 120, 1.6% of all cases). Studies that included only CSF fistula repairs had a lower average total complication rate (12.9%) but a greater rate of meningitis compared with studies that reported mixed pathology (2.4% vs. 1.3%). A trend towards a lower total complication rate with increasing study size was observed.

CONCLUSIONS

The endoscopic approach is an increasingly accepted technique for anterior skull base tumor surgery and is associated with acceptable complication rates. Increasing experience with this technique can decrease rates of complications.

[A simple and reliable technique for the treatment of rhinoliquorrhoea from small defects: Free nasal mucosa overlay graft]

INTRODUCTION

Cerebrospinal fluid leaks to the sinonasal cavities (rhinoliquorrhoea) represent a process with diagnostic and therapeutic difficulties. The endoscopic transnasal approach is the method of choice, but with many possible variants. The purpose of this paper was to make a critical review of our diagnostic and therapeutic protocol used for 11years.

MATERIAL AND METHODS

We operated on 31patients. The diagnosis was based on the biochemical analysis of rhinorrhoea, CT and MRI.

TREATMENT

endoscopic nasal surgery after preoperative intrathecal injection of 5% fluorescein (2cc). Closure was performed using a free overlay graft from middle turbinate mucosa.

RESULTS

Two patients had meningitis as the first sign. All patients were diagnosed by biochemical analysis of rhinorrhoea. CT and MRI gave clear evidence of the leakage location. The skull base defect was always less than 1cm. Fluorescein allowed clear visualisation of the fistulous area without other instruments and produced no side effects. One patient had a postoperative frontal abscess, which evolved favourably. All fistulas were closed and there was only one recurrence at 10years, which debuted as pneumococcal meningitis.

DISCUSSION AND CONCLUSIONS

Our surgical protocol, based on the use of intrathecal fluorescein and free grafting of middle turbinate mucosa overlay onto the fistulous area, achieves successful long-term results in the management of rhinoliquorrhoea secondary to small skull base defects.

Diagnosis and treatment of cerebrospinal fluid rhinorrhea following accidental traumatic anterior skull base fractures

Cerebrospinal fluid rhinorrhea is a serious and potentially fatal condition because of an increased risk of meningitis and brain abscess. Approximately 80% of all cases occur in patients with head injuries and craniofacial fractures. Despite technical advances in the diagnosis and management of CSF rhinorrhea caused by craniofacial injury through the introduction of MRI and endoscopic extracranial surgical approaches, difficulties remain. The authors review here the pathophysiology, diagnosis, and management of CSF rhinorrhea relevant exclusively to traumatic anterior skull base injuries and attempt to identify areas in which further work is needed.

The transnasal approach to the skull base. From sinus surgery to skull base surgery

The indications for endonasal endoscopic approaches to diseases of the skull base and its adjacent structures have expanded considerably during the last decades. This is not only due to improved technical possibilities such as intraoperative navigation, the development of specialized instruments, and the compilation of anatomical studies from the endoscopic perspective but also related to the accumulating experience with endoscopic procedures of the skull base by multidisciplinary centers. Endoscopic endonasal operations permit new approaches to deeply seated lesions and are characterized by a reduced manipulation of neurovascular structures and brain parenchyma while at the same time providing improved visualization. They reduce the trauma caused by the approach, avoid skin incisions and minimize the surgical morbidity. Transnasal endoscopic procedures for the closure of small and large skull base defects have proven to be reliable and more successful than operations with craniotomies. The development of new local and regional vascularized flaps like the Hadad-flap have contributed to this. These reconstructive techniques are furthermore effectively utilized in tumor surgery in this region. This review delineates the classification of expanded endonasal approaches in detail. They provide access to lesions of the anterior, middle and partly also to the posterior cranial fossa. Successful management of these complex procedures requires a close interdisciplinary collaboration as well as continuous education and training of all team members.

Endoscopic endonasal skull base surgery

Skull base surgery has been transformed by the development of endoscopic techniques. Endoscopic procedures were first used for pituitary surgery and were then gradually extended to other regions. A wide range of diseases are now accessible to endoscopic skull base surgery. The major advantage of the endoscopic endonasal approach is that it provides direct anatomical access to a large number of intracranial and paranasal sinus lesions, avoiding the sequelae of a skin incision, facial bone flap or craniotomy, and brain retraction, which is inevitable with conventional neurosurgical incisions, resulting in decreased morbidity and mortality and, indirectly, decreased length of hospital stay and management costs. Moreover, the increasing number of publications in this field illustrates the growing interest in these techniques. This paper provides a review of endoscopic skull base surgery. The indications and general principles of endoscopic endonasal skull base surgery are described. Progress in exposure and especially reconstruction techniques is described. This progress now allows more extensive resections, while maintaining acceptable morbidity. The limits of this surgery are also discussed; in particular, although this surgery is often described as "minimally invasive", it is not completely devoid of morbidity.

Image-guided endoscopic repair of cerebrospinal fluid rhinorrhea by the bath plug grafting technique

OBJECTIVES/HYPOTHESIS

Several techniques of endoscopic repair of cerebrospinal fluid (CSF) rhinorrhea were prescribed. Defect localization was mandatory for all.

STUDY DESIGN

Prospective study.

METHODS

A prospective study was conducted on nonaccidental CSF rhinorrhea. The sensitivity and specificity of image-guided navigation in localizing the defect were studied. The feasibility and reliability of the bath plug technique in repairing the defect were assessed. Six cases were included.

RESULTS

CFS rhinorrhea was spontaneous in four and iatrogenic in two. Two defects were in the fovea ethmoidalis, two in the cribriform plate, and two in the sphenoid. The repairing graft was successfully positioned in five cases. In one case a sphenoid obliteration was done. Image-guided navigation proved useful in localizing the defect with a sensitivity and specificity of 100%. All patients were available for follow-up (mean = 19 months). The overall success rate was 83%, and the mean number of surgeries per patient was one.

CONCLUSIONS

The bath plug was feasible for repairing the anterior skull base defects but not for all the sphenoid defects. It proved reliable as a single management in cases with normal intracranial pressure. The image-guided navigation overrides, in sensitivity and specificity, other methods of localization of the anterior skull base defects.

Extended applications of endoscopic sinus surgery and its reference to cranial base and pituitary fossa

Sinus surgery has the potential of allowing ENT surgeons to encroach the boundaries of our colleagues in ophthalmology and neurosurgery. The advent of nasal endoscope and lately powered instrumentation and computer-assisted navigational systems has avoided the use of the conventional and more radical approaches by the ENT surgeon for the treatment of inflammatory pathology or tumors of the orbit and skull base. As rhinologists have gained more experience in endoscopic surgery, more areas related to the orbit and the anterior skull base are accessible and surgery is safer.

Endoscopic repair of cerebrospinal fluid leaks in the lateral sphenoid sinus recess

OBJECT

Cerebrospinal fluid leaks may occur as a result of trauma or following surgery, and occasionally may also be spontaneous. Leakage of CSF from the lateral sphenoid recess is rare and challenging to treat. The authors present their experience with repairs of 10 CSF leaks that were confined to the lateral sphenoid recess and were treated at the Singapore General Hospital.

METHODS

A retrospective chart review was conducted for all patients who underwent operations for lateral sphenoid recess CSF leaks between 2001 and 2008.

RESULTS

Ten repairs were performed in 8 patients by using a transpterygoid approach, with a 90% success rate. In 3 cases the transcranial approach had failed prior to endoscopic repair. "Sandwich reconstruction" under direct vision was performed in all cases, and was completed using cartilage or bone as a rigid support.

CONCLUSIONS

This series demonstrates that CSF leakage can be managed safely and effectively by using an endoscopic transpterygoid approach in patients in whom both external and endoscopic attempts have failed. The transpterygoid approach used in all of the cases in this series provides wide exposure around the skull base defect, which is crucial for successful repair.

[Endoscopic management of cerebrospinal fluid rhinorhea]

Endoscopic surgery due to its high efficacy and relatively minor intraoperative trauma became a standard of transnasal csf leak treatment.

THE AIM OF THIS STUDY

was to present, basing on our own experience, diagnostic and therapeutic methods of treatment of various types of csf rhinorhea.

MATERIAL AND METHOD

All together 14 endoscopic skull base reconstructions were performed. The bony defect and dural perforations were closed using: fat grafts, septal bone or cartilage, mucosal flaps of the septum or nasal concha, artificial dura and collagen sponge with fibrin glue. The defect was localized by high resolution computed tomography, magnetic resonance cisternography, neuronavigation system and fluorecein test.

RESULTS

Complete closure of the defect and resolution of the csf leak after the first attempt was achieved in 92,3% of patients. In one case the rhinorhea was successfully stopped after the second reconstructive procedure. No adverse reaction of intrathecal fluorescein administration were noted in our patients.

CONCLUSIONS

Endoscopic surgeons have a wide variety of diagnostic tools and operative techniques at their disposal for precise localization and management of csf rhinorhea. The key for high efficacy of the treatment is appropriate selection of diagnostic and surgical method depending on cause, type, size and localization of the leak.

Tension pneumocephalus and rhinorrhea revealing spontaneous cerebrospinal fluid fistula of the anterior cranial base

Spontaneous cerebrospinal fluid fistulas (CSFFs) of the anterior skull base are extremely rare. We report a case of spontaneous CSFF of the ethmoid cribriform plate presenting with rhinorrhea and tension pneumocephalus. We discuss the physiopathology, the radiological management, and the treatment of spontaneous CSF fistulas related to the anterior skull base. A 58-year-old woman was admitted to our institution for headaches with clear rhinorrhea persisting over several days. Antecedents were unremarkable. An episode of epistaxis three days before was reported. Clinical examination showed clear rhinorrhea, headaches, and anosmia. The CT scan showed voluminous epidural and subdural pneumocephalus with mass effect on both frontal and temporal lobes. A high-resolution CT scan with bone reconstruction showed a 2-mm bony defect of the cribriform plate. Surgery consisted of epidural frontal anterior skull base repair. Postsurgery follow-up was uneventful. At one year, the patient was asymptomatic apart from the persistence of anosmia. Spontaneous CSF fistulas are uncommon and can be associated with tension pneumocephalus. The physiopathology remains unclear. Their treatment by complete exclusion of the fistula is necessary because of the lethal risk of pneumococcus meningitis.

Evaluation of spontaneous nasal cerebrospinal fluid leaks

PURPOSE OF REVIEW

Spontaneous nasal cerebrospinal fluid (CSF) leaks represent a distinct clinical entity that presents important diagnostic and therapeutic challenges. Recognition of the proper demographic group and presenting symptoms, as well as the radiologic features of this disease process, are integral to making the appropriate diagnosis. In addition, this patient group requires special perioperative and intraoperative considerations for suitable management.

RECENT FINDINGS

Current literature echoes previously published success rates for endoscopic repair of CSF leaks at or above 90%. Success rates for closure of spontaneous CSF leaks, however, continue to be the lowest in comparison with other CSF leak etiologies. The increased failure rate for spontaneous CSF leak repair is likely due to the increased intracranial pressure present in this patient group. Patients with spontaneous CSF leaks are increasingly being recognized as belonging to a group inclusive of patients with benign intracranial hypertension and empty sella syndrome.

SUMMARY

In this review, we highlight the demographic characteristics, clinical presentation and radiologic findings that distinguish spontaneous nasal CSF leak patients from those with other CSF leak etiologies. We also discuss perioperative measures advocated for patients with spontaneous nasal CSF leaks that may aid in the success of their surgical repair.