Diagnosis of cerebrospinal fluid rhinorrhea: an evidence-based review with recommendations

Systematic review of errors on beta-2 transferrin gel electrophoresis testing of rhinorrhea and otorrhea

BACKGROUND

Beta-2 transferrin (B2-Tf) gel electrophoresis (GE) is the preferred non-invasive diagnostic modality for confirming cerebrospinal fluid (CSF) in body fluids. While B2-Tf GE testing is highly sensitive and specific for CSF, false-positive (FP) and false-negative (FN) results can lead to diagnostic and therapeutic dilemmas. Several series have demonstrated potential causes of false B2-Tf GE results, but few studies have reported reasons for these errors. The purpose of this systematic review was to describe sources of B2-Tf GE errors.

METHODS

A systematic review was performed by searching OVID, EMBASE, and Web of Science databases for B2-Tf GE studies. After applying exclusion criteria, original research studies directly addressing erroneous B2-Tf GE results underwent qualitative analysis.

RESULTS

Of the 243 abstracts screened, 71 underwent full-text review and 18 studies reporting B2-Tf GE errors were included for analysis. There were 15 potential FPs, 12 actual FPs, 12 potential FNs, 19 actual FNs, and 14 indeterminate results. There were also 246 potentially indeterminate results from in vitro studies. Reasons for B2-Tf GE errors included serum transferrin alterations (n = 17; all potential), infection related (n = 13; 9 potential), orbital or salivary contamination (n = 2; 1 potential), and collection related (n = 255; 246 potential). There were 31 false or indeterminate results with unspecified reasons. There were no reported errors due to laboratory processing.

CONCLUSIONS

Multiple potential or actual reasons for false or indeterminate results have been reported for B2-Tf GE testing of rhinorrhea and otorrhea. Future studies should explore reasons for B2-Tf testing errors and how these may affect clinical decision making.

Multimodal diagnosis of cerebrospinal fluid rhinorrhea: State of the art review and emerging concepts

Objective

Currently, diagnosis of cerebrospinal fluid (CSF) rhinorrhea relies on a multimodal approach, increasing costs and ultimately delaying diagnosis. In the United States and internationally, the crux of such a diagnosis relies on confirmation testing (via biomarkers) and localization (e.g., imaging). Biomarker testing may require analysis at an outside facility, resulting in delays diagnosis and treatment. In addition, specialized imaging may be nonspecific and often requires an active leak for diagnosis. There remains a clear need for innovative new technology.

Methods

A comprehensive review was conducted on both foundational and innovative scholarly articles regarding current and emerging diagnosis modalities for CSF.

Results

Current modalities in CSF rhinorrhea diagnosis and localization include laboratory tests (namely, B2T immunofixation), imaging (CT and/or MRI) with or without intrathecal administration, and surgical exploration. Each of these modalities carry flaws, risks, and benefits, ultimately contributing to delays in diagnosis and morbidity. Promising emerging technologies include lateral flow immunoassays (LFI) and biologically functionalized field-effect transistors (BioFET). Nevertheless, these carry some drawbacks of their own, and require further validation.

Conclusion

CSF rhinorrhea remains a challenging diagnosis, requiring a multimodal approach to differentiate from nonpathologic causes of rhinorrhea. Current methods in diagnosis are imperfect, as the ideal test would be a readily accessible, inexpensive, rapid, highly accurate point-of-care test without the need for excess fluid or specialized processing. Critical work is being done to develop promising, new, improved tests, though a clear successor has not yet emerged.

Level of Evidence

N/A.

Clinical Biomarkers in Otolaryngology-Head and Neck Surgery

OBJECTIVE

The purpose of this paper is to review the literature and compile promising and clinically relevant biomarkers in otolaryngology-head & neck surgery not related to autoimmune disorders.

STUDY DESIGN

Narrative review.

METHODS

PubMed and Google Scholar were queried using combined key words such as "biomarkers" and "otolaryngology." Additional queries were made with combined key words such as "biomarkers" and a particular subspecialty such as "rhinology" or "otology" to maximize yield of relevant titles. Subsequently, specific biomarkers identified, such as "beta-2 transferrin," were used as key words. Relevant titles were reviewed and selected for abstract review. Applicable abstracts were then selected for review of the full text.

RESULTS

Biomarkers currently in clinical use within the field of otolaryngology were included in this review. The compiled biomarkers were then detailed individually regarding their molecular characteristics, function, and clinical significance.

CONCLUSIONS

The number of biomarkers in use in otolaryngology is rapidly expanding representing a new diagnostic modality for our field. This review defines the key biomarkers that are currently or likely to be soon translated into clinical use within the field of otolaryngology. The majority of these biomarkers are in the form of proteins such as beta-2 transferrin, thyroglobulin, and P16. Given their growing impact on diagnosis, management and surveillance of otolaryngologic disorders periodic surveys are needed for education and to guide further advances and applications of otolaryngologic biomarkers.

[Cerebrospinal fluid rhinorrhea secondary to ethmoidal carcinoma: case report]

BACKGROUND

The first report of cerebrospinal fluid rhinorrhea (CSFR) was described in 1679. In 1826 it was reported that one of the possible causes of CSFR was a fistula between the subarachnoid space and the nasal cavity. In 1903, chemical analysis of the fluid was proposed as a diagnostic criterion. In Mexico there has been 32 case reports.

CASE REPORT

Forty-nine years old female with a history of nasal polyposis, profuse rhinorrhea and cephalea who attends the allergy department with the suspicion of allergic rhinitis. After anamnesis and physical evaluation, CSFR was suspected. Chemical analysis of the fluid, head CT and biopsy of nasal polyp were performed. An etmoidal fistula associated with carcinoma was confirmed.

CONCLUSIONS

Spontaneous fistulas are rare but can erosionate the bone and adjacent tissues. Diagnosis is based on the clinical findings, patient's history and complementary studies such as beta-2-transferrin determination in nasal fluid.

Endoscopic Repair of Cerebrospinal Fluid Rhinorrhea Due to Trauma by a Bamboo Stick in a Pediatric Patient

Cerebrospinal fluid rhinorrhea (CSFR) is a condition in which the cerebrospinal fluid flows out of the nasal cavity due to rupture of the arachnoid, dura, and nasal membranes because of bone defects in the skull base. The authors report a rare case of CSFR in a 2-year-old girl who experienced trauma in the nasal cavity by a bamboo stick. She underwent endoscopic repair for the CSFR. During surgery, a bulged vesicle was observed at the left cribriform plate with a small amount of cerebrospinal fluid draining from the surrounding area. Postoperative recovery was good. Endoscopic CSFR repair in pediatric patients is minimally invasive, effective, and safe as demonstrated in this case. Prevention of CSFR in children is important. Parents and caretakers of children need to be more aware, and potentially dangerous objects should not be kept within reach of children.

Using Ipratropium Bromide Nasal Spray Response as a Screening Tool in the Diagnostic Workup of Cerebrospinal Fluid Rhinorrhea

OBJECTIVES

Unilateral clear thin rhinorrhea (UCTR) can be concerning for a nasal cerebrospinal fluid (CSF) leak. Beta-2 transferrin electrophoresis has been the gold standard for initial non-invasive confirmatory testing for CSF rhinorrhea, but there can be issues with fluid collection and testing errors. Ipratropium bromide nasal spray (IBNS) is highly effective at reducing rhinitis-related rhinorrhea, and should presumably not resolve CSF rhinorrhea. This study assessed whether different clinical features and IBNS response helped predict presence or absence of CSF rhinorrhea.

METHODS

A prospective cohort study was conducted where all patients with UCTR had nasal fluid tested for beta-2 transferrin, and were prescribed 0.06% IBNS. Patients were diagnosed with CSF rhinorrhea or other rhinologic conditions. Clinical variables like IBNS response (rhinorrhea reduction), positional worsening, salty taste, postoperative state, female gender, and body-mass index were assessed for their ability to predict CSF rhinorrhea. Sensitivity, specificity, and predictive values and odds ratios were calculated for all clinical variables.

RESULTS

Twenty patients had CSF rhinorrhea, and 53 had non-CSF etiologies. Amongst clinical variables assessed for predicting CSF absence or presence, significant associations were shown for IBNS response (OR = 844.66, p = 0.001), positional rhinorrhea worsening (OR = 8.22, p = 0.049), and body-mass index ≥30 (OR = 2.92, p = 0.048). IBNS response demonstrated 96% sensitivity and 100% specificity, and 100% positive and 91% negative predictive values for predicting CSF rhinorrhea.

CONCLUSIONS

In patients with UCTR, 0.06% IBNS response is an excellent screening tool for excluding CSF rhinorrhea, and should be considered in the diagnostic workup of CSF rhinorrhea.

LEVEL OF EVIDENCE

2 Laryngoscope, 134:56-61, 2024.

Radionuclide Cisternography with [64Cu]Cu-DOTA

Radionuclide cisternography (RNC) is a method for conducting imaging of the cerebrospinal system and can be used to identify cerebrospinal fluid leaks. So far, RNC has commonly employed radiopharmaceutical agents suitable only for single-photon emission tomography techniques, which are thus lacking in terms of image resolution and can potentially lead to false-negative results. Therefore, [64Cu]Cu-DOTA was investigated as an alternative radiopharmaceutical for RNC, employing positron emission tomography (PET) instead of single-photon emission tomography. A formulation of [64Cu]Cu-DOTA was produced according to the guidelines for good manufacturing practice. The product met the requirements of agents suitable for intrathecal application. [64Cu]Cu-DOTA was administered to a patient and compared to the approved scintigraphic RNC agent, [111In]In-DTPA. While no cerebrospinal fluid leak was detected with [111In]In-DTPA, [64Cu]Cu-DOTA RNC exhibited a posterolateral leak between the vertebral bodies C1 and C2. Thus, in this patient, PET RNC with [64Cu]Cu-DOTA was superior to RNC with [111In]In-DTPA. Since radiopharmaceuticals have a very good safety profile regarding the occurrence of adverse events, PET RNC with [64Cu]Cu-DOTA may become an attractive alternative to scintigraphic methods, and also to computed tomography or magnetic resonance imaging, which often require contrast agents, causing adverse events to occur much more frequently.

SNOT-22 Quality of Life Scores Improve After Endoscopic Endonasal Repair of Spontaneous Cerebrospinal Fluid Rhinorrhea

OBJECTIVES

Patients with spontaneous cerebrospinal fluid (CSF) rhinorrhea can experience significant sinonasal symptom burden, leading to poor quality of life (QOL). The objective of this study was to investigate sinonasal outcome test-22 (SNOT-22) scores in patients undergoing endoscopic endonasal surgery for spontaneous CSF rhinorrhea and compare them to patients undergoing endoscopic sinus surgery (ESS) for chronic rhinosinusitis without nasal polyps (CRSsNP).

METHODS

A multi-institutional retrospective review of patients with spontaneous CSF rhinorrhea and CRSsNP was performed. Pre-surgery and post-surgery SNOT-22 scores and domains were compared within each group. Improvements in SNOT-22 scores after surgery were compared between the groups.

RESULTS

Ninety-one patients were in the CSF rhinorrhea group and 105 patients were in the CRSsNP group. Within each group, surgery significantly improved total SNOT-22 scores, domain scores, and most of the individual symptoms. Comparing the 2 groups revealed similar improvements in total SNOT-22 scores (P = .244). The CSF rhinorrhea group improved more in runny nose (P < .001), postnasal discharge (P < .001), wake up at night (P = .024), and embarrassed (P = .002). The CRSsNP group improved more in sneezing (P = .027), nasal blockage (P < .001), decreased sense of smell/taste (P = .011), thick nasal discharge (P < .001), facial pain/pressure (P = .008), and the ear/facial domain (P = .010).

CONCLUSIONS

Patients with spontaneous CSF rhinorrhea experience significant symptom burden. Those who undergo CSF leak repair should experience significant improvement in QOL similar to patients who undergo ESS for CRSsNP as measured by SNOT-22.

Anterior Skull Base Reconstruction

Anterior skull base reconstruction requires careful preoperative planning to use the most effective technique for the expected defect. Adherence to the principles of skull base reconstruction is imperative to minimize complications and improve patient outcomes.

International consensus statement on allergy and rhinology: Allergic rhinitis - 2023

BACKGROUND

In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document.

METHODS

ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work.

RESULTS

ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost.

CONCLUSION

The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

High-Resolution Computed Tomography as an Initial Diagnostic and Localization Tool in Patients with Cerebrospinal Fluid Rhinorrhea: A Meta-Analysis

Background and Objectives: This study was performed to investigate the utility of high-resolution computed tomography (HRCT) for the initial localization of cerebrospinal fluid rhinorrhea. Methods: HRCT data regarding the point of cerebrospinal fluid leakage (as confirmed in the operating room), collected up to December 2022, were extracted from five databases. The risk of bias of the included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Results: The search revealed eight relevant studies with a total of 254 patients. The diagnostic odds ratio of the imaging studies was 10.0729 (95% confidence interval [CI]: 2.4486; 41.4376; I2 = 54.1%). The area under the summary receiver operating characteristic curve was 0.8. Sensitivity, specificity, the negative predictive value, and the positive predictive value were 0.7550 (95% CI: 0.6163; 0.8553; I2 = 69.8%), 0.8502 (95% CI: 0.5986; 0.9557, I2 = 49.3%), 0.4106 (95% CI: 0.2418; 0.6035; I2 = 59.0%), and 0.9575 (95% CI: 0.8955; 0.9834; I2 = 27.7%), respectively. Conclusions: HRCT can be used to accurately localize cerebrospinal fluid rhinorrhea because it shows bony defects in high detail. However, it has limited utility for the evaluation of active leakage, and localization is difficult in the presence of coexisting lesions.

A 58-year-Old non-smoking woman with intractable cough and rhinorrhea

Our case highlights an uncommon cause of CSF rhinorrhea. The patient was diagnosed with bacterial meningitis and appropriately treated after which, she developed unilateral rhinorrhea followed by non-productive cough. These symptoms were not responsive to multiple treatment regimens, and eventually imaging revealed a dehiscence in the ethmoid air sinus which was surgically repaired. We also performed a literature review on CSF rhinorrhea and provide insights into its evaluation.

[Diagnosis and Treatment in frontobasal fractures]

Traumatic brain injury can result in frontobasal fractures (FBF). The goals of treatment for FBF are to eliminate primary morbidity and/or prevent secondary morbidity. Of particular importance in this regard is the proximity of important sensory organs for hearing, vision, smell, and taste, as well as their supplying nervous structures. Medical history, clinical findings, or CT scan are necessary and should lead to an individual evaluation. Depending on the severity of the fractures, the following disciplines may be involved in the treatment of FBF: neurosurgery, plastic surgery, oral and maxillofacial surgery, and/or otorhinolaryngology. Particularly less invasive endoscopic endonasal therapy is a specialty of otorhinolaryngologic surgeons and has not been widely established in other disciplines. The present work provides an overview of the current state of the art in terms of the following aspects, taking into account the current literature: anatomic principles, classification of fractures, diagnostics (in particular clinical examination, imaging, and laboratory chemistry tests), clinical symptoms, and treatment.

Postoperative protocols following endoscopic skull base surgery: An evidence-based review with recommendations

BACKGROUND

Postoperative management strategies for endoscopic skull base surgery (ESBS) vary widely because of limited evidence-based guidance.

METHODS

The PubMed, EMBASE, and Cochrane databases were systematically reviewed from January 1990 through February 2022 to examine 18 postoperative considerations for ESBS. Nonhuman studies, articles written in a language other than English, and case reports were excluded. Studies were assessed for levels of evidence, and each topic's aggregate grade of evidence was evaluated.

RESULTS

A total of 74 studies reporting on 18 postoperative practices were reviewed. Postoperative pain management, prophylactic antibiotics, and lumbar drain use had the highest grades of evidence (B). The literature currently lacks high quality evidence for a majority of the reviewed ESBS precautions. There were no relevant studies to address postoperative urinary catheter use and medical intracranial pressure reduction.

CONCLUSION

The evidence for postoperative ESBS precautions is heterogeneous, scarce, and generally of low quality. Although this review identified the best evidence available in the literature, it suggests the urgent need for more robust evidence. Therefore, additional high-quality studies are needed in order to devise optimal postoperative ESBS protocols.

Endoscopic Endonasal Skull Base Surgery Complication Avoidance: A Contemporary Review

The endoscopic endonasal approach (EEA) provides a direct trajectory to ventral skull base lesions, avoidance of brain retraction, and clear visualization of cranial nerves as they exit skull base foramina. Despite these benefits, the EEA is not without complications. Here, we review published literature highlighting complications associated with the EEA including cerebrospinal fluid (CSF) leak, cranial nerve (CN) dysfunction, pituitary gland dysfunction, internal carotid artery (ICA) injury, infection, and others; we place special emphasis on discussing the prevention of these complications. As widespread adoption of the EEA continues, it becomes critical to educate surgeons regarding potential complications and their prevention while identifying gaps in the current literature to guide future research and advances in clinical care.

[Diagnostic value of computed tomographic cisternography and magnetic resonance hydrography in cerebrospinal fluid rhinorrhea]

Objective:To evaluate the accuracy of preoperative computed tomographic cisternography（CTC） and magnetic resonance hydrography（MRH）in the diagnosis of cerebrospinal fluid（CSF） rhinorrhea. Methods:Retrospective analysis was made on the data of 38 patients diagnosed as cerebrospinal rhinorrhea who completed preoperative HRCT, CTC and MRH examinations in the Department of Otolaryngology Head and Neck Surgery of Tianjin Huanhu Hospital from October 2016 to January 2022. The diagnostic accuracy of preoperative imaging examinations was compared according to the leak location found during operation. Results:Among all the 38 cases with CSF rhinorrhea, the detection rates of HRCT, CTC, and cranial MRH were 31.58%, 89.47%, and 60.53%, respectively. The accuracy of CTC was significantlyhigher than that of MRH （ χ²=8.49, P=0.007）, and the accuracy of MRH was significantly higher than that of HRCT （χ²=6.41, P=0.01）. Subgroup analyses were performed according to the precise positioning of cerebrospinal fluid rhinorrhea leakage. In patients with cerebrospinal fluid rhinorrhea located in ethmoid sinus, the accuracy of CTC（80.95% vs. 14.29%，P<0.01）and MRH（52.38% vs. 14.29%，P=0.02）were significantly higher than that of HRCT, but the accuracy but the difference between CTC and MRH between CTC and MRH was not statistically significant （P=0.10）. The accuracy of CTC was significantly higher than that of MRH （100.00% vs. 61.54%, P=0.04） and HRCT （100.00% vs. 53.85%, P<0.01） in patients with CSF rhinorrhea located in sphenoid sinus. However, there was no significant difference in the accuracy between MRH and HRCT （ P=1.00）. However, There was no significant difference in the accuracy of CTC, MRH and HRCT in patients with cerebrospinal fluid rhinorrhea located in frontal sinus. The accuracy of CTC and MRH was 84.62% and 57.69% respectively in 26 patients who failed to detect a CSF rhinorrhea by HRCT, and the difference was not statistically significant（χ²=4.59, P=0.06）. Conclusion:The comprehensive application of the multiple imaging methods has important guiding significance for the accurate treatment and prognosis evaluation. CTC and MRH could improve the accuracy of the localization diagnosis of cerebrospinal fluid rhinorrhea.

Efficacy of Imaging Methods in the Detection and Diagnosis of Cerebrospinal Fluid Rhinorrhea

OBJECTIVE

To assess the diagnostic efficacy of various imaging methods in patients with suspected cerebrospinal fluid (CSF) rhinorrhea.

DATA SOURCES

The PubMed, EMBASE, SCOPUS, Web of Science, Cochrane Trials, and Google Scholar databases were searched up to December 2021.

REVIEW METHODS

Diagnostic accuracy was compared among seven radiological methods: computed tomography (CT), CT cisternography (CTC), magnetic resonance imaging (MRI), magnetic resonance cisternography (MRC), CT + MRI, radionuclide cisternography, and intrathecal gadolinium (Gd)-MRC. Sensitivity, specificity, and accuracy were used as outcomes of the analysis. Both a traditional pairwise meta-analysis and a network meta-analysis were performed.

RESULTS

Twenty-three trials were included in the analysis. The results of a network meta-analysis performed on a network consisting of seven diagnostic methods showed that all imaging modalities had greater diagnostic accuracy than CT, with the exception of CTC, which had lower sensitivity. Only intrathecal Gd-MRC was significantly superior to other imaging methods with regard to sensitivity and accuracy. Gd-MRC also showed the greatest surface under the cumulative ranking curve values for all of the outcomes (sensitivity: 0.9200; specificity: 0.8364; accuracy: 0.8920).

CONCLUSION

This network meta-analysis demonstrates that intrathecal Gd-MRC is the most useful diagnostic method to detect CSF rhinorrhea. Laryngoscope, 2022.

Exploration of the causes of cerebrospinal fluid leakage after endoscopic endonasal surgery for sellar and suprasellar lesions and analysis of risk factors

Objective

Postoperative cerebrospinal fluid (CSF) leakage following endoscopic endonasal surgery (EES) is a frequent complication. This study aims to identify potential risk factors of postoperative CSF leakage.

Methods

A retrospective review of 360 patients who underwent EES was included. The associations between postoperative CSF leakage and patient demographics, medical history, tumor characteristics, and intraoperative repair techniques were analyzed; the diagnosis and repair of postoperative CSF leakage were also introduced.

Results

Postoperative CSF leakage occurred in 14 patients (3.9%), 2 of them cured by lumbar cistern drainage, 12 underwent endoscopic repair. Among these 12 cases, 3 were repaired twice, and the rest were cured the first time. During the repair surgery, insufficient embedded fat was detected in one case detected, seven with breached inner artificial dura, three had vascularized pedicle nasoseptal flap (VP-NSF) displacement, two with VP-NSF perforation, two with VP-NSF inactivation, and one with imperfect adherence to VP-NSF to the skull base. Eight cases had intracranial infections. Excluding one case who died of severe intracranial infection, the rest were cured and discharged without obvious sequelae. Multivariate analysis revealed that the suprasellar lesion, subarachnoid invasion, and intraoperative grade 3 flow CSF leakage were the risk factors of CSF leakage after operation, while the bone flap was a protective factor.

Conclusion

Bone flap combined with VP-NSF and iodoform gauze for skull base reconstruction is recommended in high-risk patients, while postoperative lumbar cistern drain remains dispensable.

Diagnostic Value of Radioisotope Cisternography Using 111In-DTPA in a Patient with Rhinorrhea and Purulent Meningitis

Cerebrospinal fluid (CSF) leakage is a rare condition. Prompt diagnosis and early treatment of CSF leakage minimizes the risk of severe complications such as bacterial meningitis. Different diagnostic modalities are used to detect the site of CSF leakage but often with unreliable results. The literature offers limited evidence-based guidance on the diagnostic approach for rhinorrhea. Correct localization of the defect is the mainstay for successful surgical treatment. Herein, we describe a case of recurrent meningitis due to cranio-nasal fistula and rhinorrhea successfully localized with radioisotope cisternography (RIC). We provide a detailed and practical overview of the RIC procedure and compare different imaging modalities used to detect the site of CSF leakage.

ACR Appropriateness Criteria® Sinonasal Disease: 2021 Update

This article presents guidelines for initial imaging utilization in patients presenting with sinonasal disease, including acute rhinosinusitis without and with suspected orbital and intracranial complications, chronic rhinosinusitis, suspected invasive fungal sinusitis, suspected sinonasal mass, and suspected cerebrospinal fluid leak. CT and MRI are the primary imaging modalities used to evaluate patients with sinonasal disease. Given its detailed depiction of bony anatomy, CT can accurately demonstrate the presence of sinonasal disease, bony erosions, and anatomic variants, and is essential for surgical planning. Given its superior soft tissue contrast, MRI can accurately identify clinically suspected intracranial and intraorbital complications, delineate soft tissue extension of tumor and distinguish mass from obstructed secretions.The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Cough as a neurological sign: What a clinician should know

Cough is a common respiratory complaint driving patients to seek medical advice. Besides being a fundamental respiratory sign, it is also a crucial neurological sign. There are three main types of coughs: Reflex cough (type I), voluntary cough (type II), and evoked cough (type III). Cough is a reflex predominantly mediated by control centers in the respiratory areas of the brainstem, modulated by the cerebral cortex. Cough reflex sensitivity could be increased in many neurological disorders such as brainstem space-occupying lesions, medullary lesions secondary to Chiari type I malformations, tics disorders such as Tourette's syndrome, somatic cough, cerebellar neurodegenerative diseases, and chronic vagal neuropathy due to allergic and non-allergic conditions. Meanwhile, cough sensitivity decreases in multiple sclerosis, brain hypoxia, cerebral hemispheric stroke with a brainstem shock, Parkinson's disease, dementia due to Lewy body disease, amyotrophic lateral sclerosis, and peripheral neuropathy as diabetic neuropathy, hereditary sensory and autonomic neuropathy type IV, vitamin B12, and folate deficiency. Arnold's nerve ear-cough reflex, syncopal cough, cough headache, opioids-associated cough, and cough-anal reflex are signs that could help diagnose underlying neurological conditions. Cough reflex testing is a quick, easy, and cheap test performed during the cranial nerve examination. In this article, we reviewed the role of cough in various neurological disorders that increase or decrease cough sensitivity.

Utility of Neuroimaging in the Management of Chronic and Acute Headache

Imaging plays an important role in identifying the cause of the much less common secondary headaches. Such headaches may be caused by a variety of pathologic conditions which can be categorized as intracranial and extracranial. Idiopathic intracranial hypertension imaging findings include "empty sella," orbital changes, and dural venous sinus narrowing. Intracranial hypotension (ICH) is frequently caused by CSF leaks. Imaging findings include loss of the CSF spaces, downward displacement of the brain, as well as dural thickening and enhancement. Severe cases of ICH may result in subdural hematomas. A variety of intracranial and skull base tumors may cause headaches due to dural involvement. Extracranial tumors and lesions that frequently present with headaches include a variety of sinonasal tumors as well as mucoceles. Neurovascular compression disorders causing headaches include trigeminal and glossopharyngeal neuralgia. Imaging findings include displacement and atrophy of the cranial nerve caused by an adjacent arterial or venous structure.

[The value of magnetic resonance hydrography in the localization of fistula in patients with cerebrospinal fluid rhinorrhea]

Objective:To evaluate the application value of magnetic resonance hydrography in determine the leak location of patients with cerebrospinal fluid rhinorrhea. Methods:Clinical data of 58 patients with cerebrospinal fluid rhinorrhea treated in Tianjin Huanhu Hospital from February 2015 to February 2021 were analyzed retrospectively. The leak position was judged by three methods: nasal sinus coronal CT, magnetic resonance hydrography and magnetic resonance hydrography combined with nasal sinus coronal CT. The consistency of the leak position among groups determined by different imageological examination pre-operation was compared with the real leak position found during the operation. Results:The positive rate of magnetic resonance hydrography combined with coronal CT in paranasal sinuses（91.4%） was significantly higher than that of magnetic resonance hydrography（74.1%）（P>0.05）. The positive rate of magnetic resonance hydrography（74.1%） was higher than that of CT（43.1%）（P>0.01）. Conclusion:The comprehensive application of imaging examination technology has important clinical guiding significance for the correct diagnosis of cerebrospinal fluid rhinorrhea. Magnetic resonance hydrography combined with coronal CT of paranasal sinus can effectively find the leak location, which was suggested as the first choice for preoperative localization of cerebrospinal fluid rhinorrhea.

Cerebrospinal Fluid Leak Repair: Usefulness of Intrathecal Fluorescein for Correct Topographic Identification of the Skull Base Defects

BACKGROUND

In the management of cerebrospinal fluid (CSF) leak, the identification of the exact discharge spot is paramount. This process can represent a challenge for the radiologist and the surgeon. In the present study, we analyzed a series of patients affected by endonasal CSF leak who underwent endoscopic surgical reconstruction aided by the use of ITF. The purpose of this work is to assess the efficacy of intraoperative ITF in addition to computed tomography (CT) and magnetic resonance imaging for correct topographic localization of the CSF leak.

METHODS

Eighty-three patients were enrolled in the study. The main outcome was the concordance between the supposed radiologic defect site and the actual one seen intraoperatively. Recurrence-free survival was evaluated as secondary outcome.

RESULTS

ITF better defined the defect site, allowing a change in the treatment in 21 patients (25.3%), in whom nonconcordance was observed between the suspected radiologic site and the actual surgical site. Good agreement was found between the specific topographic localization (κ = 0.737; P < 0.0001), whereas fair agreement was observed considering the side of the defect (κ = 0.362; P = 0.0009) and correct identification of multiple sites (κ = 0.044; P = 0.666). The 10-year 96% estimate of recurrence-free survival confirmed the correct repair of the fistula site in most cases.

CONCLUSIONS

Our data show the usefulness and safety of intraoperative ITF for management of patients affected by endonasal CSF leak. ITF improved the topographic diagnosis of the leak site, ensuring the best target reconstruction and very low recurrence rate.

Case Report: Detection of Transferrin in a Dog Suspected of Having Cerebrospinal Fluid Rhinorrhea

A 12-year-old Yorkshire terrier was referred for epileptic seizures and nasal discharge. The fluid was clear and serous. Cerebrospinal fluid (CSF) rhinorrhea was suspected, based on clinical signs and MRI findings. In humans, analysis of nasal secretions to determine the concentration of glucose and brain-type transferrin has been widely used clinically in order to confirm the presence of CSF rhinorrhea. The glucose concentration in the nasal discharge was 74 mg/dL. Serum-type and brain-type isoforms of transferrin were detectable in the nasal sample. The concentration of glucose and brain-type transferrin could be useful for diagnosing CSF rhinorrhea.

Diagnostic Value of Non-Contrast CT in Cerebrospinal Fluid Leakage After Endoscopic Transnasal Surgery for Sellar and Suprasellar Tumors

We aimed to study the relationship between pneumocephalus on non-contrast CT (NCCT) and post-operative cerebrospinal fluid leakage (p-CFL) after endoscopic transsphenoidal sellar and suprasellar tumor surgeries. Data from patients who underwent endoscopic treatment for sellar or suprasellar tumors from January 2018 to March 2020 were consecutively collected and reviewed. The NCCT pneumocephalus (NP) was measured the first day after operation and the first day after the expansive sponge was extracted. p-CFL was determined according to post-operative clinical symptoms, high resolution CT and glucose test, and expert consensus. Of the 253 patients enrolled in this study, 32 (12.6%) had p-CFL. Compared with patients without p-CFL, patients with p-CFL had a higher occurrence of intra-operative CFL, a longer operation time, a higher rate of pneumocephalus on first-day NCCT after operation (i.e., first-day NP), and a higher rate of NP volume change between two NCCT measurements (referred to as the NP change) (all p < 0.05). In multivariate regression analysis, first-day NP was independently associated with p-CFL occurrence [odds ratio (OR)=6.395, 95% confidence interval (CI)=2.236-18.290, p=0.001). After adding the NP change into the regression model, first-day NP was no longer independently associated with p-CFL, and NP change (OR = 19.457, 95% CI = 6.095–62.107, p<0.001) was independently associated with p-CFL. The receiver operating characteristic curve comparison analysis showed that NP change had a significantly better predicting value than first-day NP (area under the curve: 0.988 vs. 0.642, Z=6.451, p=0.001). NP is an effective imaging marker for predicting p-CFL after endoscopic sellar and suprasellar tumors operation, and the NP change has a better predicting value.

Detection of Cerebrospinal Fluid Leaks Using the Endoscopic Fluorescein Test in the Postoperative Period following Pituitary and Ventral Skull Base Surgery

Objective  Diagnosis of cerebrospinal fluid (CSF) leaks is sometimes challenging in the postoperative period following pituitary and ventral skull base surgery. Intrathecal fluorescein (ITF) may be useful in this setting. Design  Retrospective chart review. Setting  Tertiary care center. Methods and Participants  All patients who underwent pituitary and ventral skull base surgery performed by a single rhinologist between January 2017 and March 2020 were included. There were 103 patients identified. Eighteen patients received 20 ITF injections due to clinical suspicion for CSF leak during the postoperative period without florid CSF rhinorrhea on clinical exam. Computed tomography scans with new or increasing intracranial air and intraoperative findings were used to confirm CSF leaks. Clinical courses were reviewed for at least 6 months after initial concern for leak as the final determinate of CSF leak. Main Outcome Measures  Specificity and safety of ITF. Results  Eleven (61%) ITF patients were female and 7 (39%) were male. Average patient age was 52.50 ± 11.89. There were six patients with confirmed postoperative CSF leaks, 3 of whom had evaluations with ITF. ITF use resulted in 2 true positives, 1 false negative, 17 true negatives, and 0 false positives. ITF sensitivity was 67%, specificity was 100%, and positive and negative predictive values were 100 and 94.4%, respectively. There were no adverse effects from ITF use. Conclusions  Existing modalities for detecting postoperative CSF leaks suffer from suboptimal sensitivity and specificity, delayed result reporting, or limited availability. ITF represents a specific and safe test with potential utility in the postoperative setting.

Cerebrospinal Fluid Leak Detection with a Carbon Nanotube-Based Field-Effect Transistor Biosensing Platform

Cerebrospinal fluid (CSF) leakage may lead to life-threatening complications if not detected promptly. However, gel electrophoresis, the gold-standard test for confirming CSF leakage by detecting beta2-transferrin (β2-Tf), requires 3-6 h and is labor-intensive. We developed a new β2-Tf detection platform for rapid identification of CSF leakage. The three-step design, which includes two steps of affinity chromatography and a rapid sensing step using a semiconductor-enriched single-walled carbon nanotube field-effect transistor (FET) sensor, circumvented the lack of selectivity that antitransferrin antibody exhibits for transferrin isoforms and markedly shortened the detection time. Furthermore, three different sensing configurations for the FET sensor were investigated for obtaining the optimal β2-Tf sensing results. Finally, body fluid (CSF and serum) tests employing our three-step strategy demonstrated high sensitivity, suggesting its potential to be used as a rapid diagnostic tool for CSF leakage.

Usefulness of imaging studies for diagnosing and localizing cerebrospinal fluid rhinorrhea: A systematic review and meta-analysis

OBJECTIVES

To evaluate the usefulness of diagnosis by imaging studies for the localization of cerebrospinal fluid rhinorrhea.

METHODS

PubMed, SCOPUS, Embase, Web of Science, and Cochrane library databases were searched up to July 2021. True and false positive and negative data were collected along with the characteristics of each study. Methodological quality was assessed using the QADAS-2 tool.

RESULTS

Sixteen studies involving 472 patients were included. The diagnostic odds ratio of imaging studies was 13.6195 (95% confidence interval [7.4756; 24.8129]; I² = 28.1%). The area under the summary receiver operating characteristic curve was 0.712. Sensitivity, specificity, negative predictive value, and positive predictive value were 0.8507 ([0.7773; 0.9029]; 72.1%), 0.7827 ([0.6865; 0.8556], 26.8%), 0.5828 ([0.4398; 0.7132]; 67.4%), and 0.9407 ([0.8935; 0.9678]; 59.1%), respectively. In subgroup analysis, there were significant differences in sensitivity (computed tomography, 0.7421; computed tomography cisternography, 0.8872; magnetic resonance imaging, 0.8365; magnetic resonance cisternography, 0.8565; and intrathecal gadolinium magnetic resonance cisternography, 0.9307; radionuclide cisteronography, 0.7097; p  =  0.0481), and negative predictive value among imaging modalities (computed tomography, 0.3028; computed tomography cisternography, 0.4848; magnetic resonance imaging, 0.4658; magnetic resonance cisternography, 0.7465; and intrathecal gadolinium magnetic resonance cisternography, 0.8611, and radionuclide cisteronography, 0.5263; p  =  0.0046). There were no significant differences among imaging modalities in specificity, positive predictive value, or diagnostic odds ratio (p > 0.05).

CONCLUSION

Imaging studies can be used in the diagnosis of cerebrospinal fluid rhinorrhea. Gadolinium magnetic resonance cisternography showed the highest diagnostic accuracy. Also, magnetic resonance cisternography showed fair diagnostic accuracy without intrathecal injection. This article is protected by copyright. All rights reserved.

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.

Recurrent Community-Acquired Bacterial Meningitis in Adults

BACKGROUND

Recurrent bacterial meningitis has been found to occur in about 5% of meningitis cases.

METHODS

We analyzed adults with recurrent episodes in a prospective nationwide cohort study of community-acquired bacterial meningitis.

RESULTS

Of 2264 episodes of community-acquired bacterial meningitis between 2006 and 2018, 143 (6%) were identified as recurrent episodes in 123 patients. The median age was 57 years (interquartile range [IQR], 43-66), and 57 episodes (46%) occurred in men. The median duration between the first and the current episode was 5 years (IQR, 1-15). For 82 of 123 patients (67%), it was the first recurrent episode, 31 patients had 2-5 previous episodes (25%), 2 had 6-10 episodes (2%), and 2 had >10 episodes (2%). Predisposing factors were identified in 87 of 118 patients (74%) and most commonly consisted of ear or sinus infections (43 of 120, 36%) and cerebrospinal fluid leakage (37 of 116, 32%). The most common pathogens were Streptococcus pneumoniae (93 of 143, 65%) and Haemophilus influenzae (19 of 143, 13%). The outcome was unfavorable (Glasgow outcome scale score, <5) in 24 episodes with recurrent meningitis (17%) vs 810 for nonrecurrent meningitis patients (39%, P < .001). Six of 143 died (4%) vs 362 of 2095 patients (17%, P < .001).

CONCLUSIONS

Recurrent meningitis occurs mainly in patients with ear or sinus infections and cerebrospinal fluid leakage. Predominant causative pathogens are S. pneumoniae and H. influenzae. The disease course is less severe, resulting in lower case fatality compared with nonrecurrent meningitis patients.

Topical Intranasal Fluorescein to Diagnose and Localize Cerebrospinal Fluid Leak: A Systematic Review

Objective:

This study evaluates the available evidence regarding using topical intranasal fluorescein (TINF) to diagnose and localize nasal cerebrospinal fluid (CSF) leak.

Methods:

A literature search was conducted through PubMed, the Cochrane Database, Scopus, and Ovid to identify the articles providing insight into using TINF to diagnose CSF leak preoperatively or to localize the leak intraoperatively. The articles from the database were screened and filtered by two authors according to the selection criteria. A spreadsheet was created to collect the data including demographic characteristics, the sensitivity and specificity of TINF for diagnosing and localizing a CSF leak, the protocol of applying TINF, and the complications.

Results:

After excluding duplicates and articles that did not meet our selection criteria, we included five reports in the final analysis. The average age of the 94 participants was 39.5, and there was an equal distribution of males and females. The sensitivity of TINF to make a preoperative diagnosis of CSF leak was 100%, and it was 97% to localize the site intraoperatively. Complications associated with TINF were not reported in any of the reports. This review showed a grade C recommendation based on five case series.

Conclusion:

Based on the current evidence, TINF cannot be recommended for standard clinical practice. It can, however, be considered in situations where other gold standard tools are unavailable since it is feasible and easy to use. A standardized control trial should be conducted to yield additional unbiased evidence.

Imaging of Acquired Skull Base Cerebrospinal Fluid Leaks

Acquired skull base cerebrospinal fluid (CSF) leaks can result from trauma, tumors, iatrogenic causes, or may be spontaneous. Spontaneous skull base CSF leaks are likely a manifestation of underlying idiopathic intracranial hypertension. The initial assessment of rhinorrhea or otorrhea which is suspected to be due to an acquired skull base CSF leak requires integration of clinical assessment and biochemical confirmation of CSF. Imaging with high-resolution CT is performed to locate osseous defects, while high-resolution T2w MRI may detect CSF traversing the dura and bony skull base. When leaks are multiple or if samples of fluid cannot be obtained for testing, then recourse to invasive cisternography may be necessary.

Color Change of Intranasal Fluorescein Cannot Detect Cerebrospinal Fluid Leaks

BACKGROUND

The color change of topical intranasal fluorescein has been used to confirm the presence of cerebrospinal fluid (CSF) during endoscopic endonasal surgery. We aimed to validate the use of topical intranasal fluorescein for CSF detection.

METHODS

Blood, CSF, saliva, and normal saline were combined with decreasing fluorescein concentrations (from 10% to 0.1%). The solutions were photographed in high definition on nasal pledgets and in 1.5-mL Eppendorf tubes. The color difference (ΔE) was objectively measured via the International Commission on Illumination coordinates. Four otolaryngologists who were unaware of the study parameters also evaluated the samples for perceptible color differences. The human eye cannot detect color differences at an International Commission on Illumination ΔE of <5.

RESULTS

All otolaryngologists agreed a color difference could be seen with blood across all fluorescein concentrations. However, a perceptible color difference between the experimental samples that excluded blood was not appreciable. Objectively, the ΔE was <5 on average for all nonblood samples when mixed with 5% and 10% fluorescein in the Eppendorf experiment. The ΔE for the nonblood samples was >5 for the remaining tested. Similarly, the average ΔE for the nonblood samples in the pledget experiment was >5 across all fluorescein concentrations. The blood ΔE was consistently >50 throughout all fluorescein concentrations in the Eppendorf experiment and >20 throughout the pledget experiment, correlating with the subjective ease of discernment between blood and the control sample in both groups.

CONCLUSIONS

Color change alone is not sufficient to determine a difference between CSF, saliva, and saline. Blood, however, is readily identified using this method. Adjunct characteristics, in addition to the color change, are necessary to properly identify an active CSF leak.

Long-term intrathecal administration of morphine vs. baclofen: Differences in CSF glycoconjugate profiles using multiglycomics

Opioid use for treatment of persistent pain has increased dramatically over the past two decades, but it has not resulted in improved pain management outcomes. To understand the molecular mechanisms of opioids, molecular signatures that arise from opioid exposure are often sought after, using various analytical methods. In this study, we performed proteomics, and multiglycomics via sequential analysis of polysialic acids, glycosaminoglycans, N-glycans and O-glycans, using the same cerebral spinal fluid (CSF) sample from patients that had long-term (>2 years), intrathecal morphine or baclofen administered via an indwelling pump. Proteomics and N-glycomics signatures between the two treatment groups were highly conserved, while significant differences were observed in polysialic acid, heparan sulfate glycosaminoglycan and O-glycan profiles between the two treatment groups. This represents the first study to investigate the potential relationships between diverse CSF conjugated glycans and long-term intrathecal drug exposure. The unique changes, observed by a sequential analytical workflow, reflect previously undescribed molecular effects of opioid administration and pain management.

[Multiple skull base defects: features of pathogenesis, diagnosis and treatment]

OBJECTIVE

To determine the risk factors of multiple skull base defects, as well as features of diagnosis and treatment of this pathology.

MATERIAL AND METHODS

A retrospective analysis included 39 patients who underwent surgery for nasal CSF leakage at the Burdenko Neurosurgical Center in 2000-2019. The study recruited patients with multiple simultant skull base defects.

RESULTS

Traumatic defects were observed in 23 (59%) patients, spontaneous defects - in 16 (41%) cases. All patients underwent endoscopic endonasal closure of skull base defects with autografts.

CONCLUSION

Multiple defects are more common in severe traumatic brain injury. The main risk factors of multiple spontaneous defects are female sex and overweight. Adequate diagnosis implies high-resolution CT (slice width 0.5-1 mm), as well as intraoperative control of all suspicious and «weak» areas. Endoscopic endonasal technique is effective and safe for multiple skull base defects (efficiency 97%).

What is the current clinical practice in pituitary adenoma surgery in Europe? European Pituitary Adenoma Surgery Survey (EU-PASS) results-technical part

Pituitary adenoma surgery has evolved rapidly in recent decades, changing clinical practice markedly and raising new challenges. There is no current consensus or guidelines for perioperative care that includes possible complication management. This study aims to determine current practice across European neurosurgical centres. We created a list of eligible departments performing pituitary adenoma surgery based on cooperation with EANS, national neurosurgical societies, and personal communication with local neurosurgeons. We contacted the chairpersons from each department and asked them (or another responsible neurosurgeon) to fill out the survey. The survey consisted of 58 questions. For further analysis, departments were divided into subgroups: "academic"/ "non-academic centre", "high-volume"/"low-volume", "mainly endoscopic"/ "mainly microscopic"/ "mixed practise", and by geographical regions. Data from 254 departments from 34 countries were obtained. The average time to complete the survey was 18 min. Notably, the endoscopic approach is the predominant surgical approach in Europe, used in 56.8% of the centres. In routine cases without intraoperative cerebrospinal fluid leak, high-volume centres are less pedantic with sellar closure when compared with low-volume centres (p < 0.001). On the other hand, when a postoperative cerebrospinal fluid leak occurs, high-volume centres are more active and indicate early reoperation (p = 0.013). Less than 15% of the participating centres perform early postoperative MRI scans. Marked variation was noted among different groups of respondents and some contentious issues are discussed. Such information can encourage useful debate about the reasons for the variations seen and perhaps help develop standardised protocols to improve patient outcomes. A future research focus is to compare European results with other regions.

From Provider to Advocate: The Complexities of Traumatic Brain Injury Prompt the Evolution of Provider Engagement

Treating a patient with traumatic brain injury requires an interdisciplinary approach because of the pervasive, profound and protean manifestations of this condition. In this review, key aspects of the medical history and review of systems will be described in order to highlight how the role of any provider must evolve to become a better patient advocate. Although this review is written from the vantage point of a vision care provider, it is hoped that patients, caregivers and providers will recognize the need for a team approach.

Reconstruction after extended endonasal approaches to the anterior cranial base: surgical techniques and current results

The development of extended endoscopic endonasal approaches (EEA) to the anterior skull base has allowed successful resection of selected extradural and intradural skull base tumors through an endonasal corridor, minimizing brain and cranial nerve manipulation. However, as the complexity of the approaches has increased, so has the need for more robust and reliable reconstructive options to minimize morbidity. Reconstructive decision-making after extended EEA for anterior skull base tumors must take into consideration multiple factors including patient characteristics (Body Mass Index, previous surgeries, and radiation), location and the size of the skull base defect. A multilayered reconstruction which includes a combination of free grafts and a vascularized flap is the standard approach to anterior skull base defects after EEA and should be applied in a stepwise manner tailored to each patient. The techniques and materials used to accomplish skull base repair are discussed, the outcomes in the literature are reviewed, and our reconstructive paradigm presented.

Community-acquired Bacterial Meningitis in Adults With Cerebrospinal Fluid Leakage

Background

Cerebrospinal fluid (CSF) leakage is a risk factor for developing bacterial meningitis.

Methods

We analyzed episodes of community-acquired bacterial meningitis associated with CSF leakage from a prospective nationwide cohort study.

Results

CSF leakage was identified in 65 episodes of 2022 episodes (3%) in 53 patients. The cause of CSF leakage was identified in 49 of 65 episodes (75%), which most commonly consisted of ear-nose-throat surgery (19 of 49 episodes [29%]) and remote head trauma (15 of 49 episodes [23%]). The episode was a recurrent meningitis episode in 38 patients (59%). Of the recurrent episodes, 27 had known CSF leakage (71%) of whom 20 (53%) had previous surgery aiming to close the leak. Nine patients (38%) with known CSF leakage had been vaccinated (23-valent pneumococcal vaccine in 9 patients, meningococcal serogroup C vaccine in 2, meningococcal serogroup A and Haemophilus influenzae type b vaccine each in 1 patient). Streptococcus pneumoniae was cultured in 33 episodes (51%) and H. influenzae in 11 episodes (17%). The most common pneumococcal serotypes were 3 (4 episodes), 35B, 9N, 38, and 15C (each 2 episodes). Haemophilus influenzae was unencapsulated in all 10 episodes with known capsule type. The outcome was unfavorable in 8 episodes (12%) and no patient died.

Conclusions

Bacterial meningitis in patients with CSF leakage has a high recurrence rate, despite surgical repair or vaccination, and outcome is generally favorable. CSF leakage should be suspected in patients with bacterial meningitis presenting with liquorrhea, recurrent meningitis, or with disease caused by H. influenzae.

Topical intranasal fluorescein to localize a cerebrospinal fluid leak: a demonstration

BACKGROUND

Intrathecal fluorescein is commonly used to localize cerebrospinal fluid leaks. This technique is invasive and associated with several potential adverse effects. The purpose of this video presentation is to demonstrate an alternative technique, the intranasal use of dilute topical fluorescein, to localize a cerebrospinal fluid leak intraoperatively.

METHODS

A 45-year-old male with a history of benign intracranial hypertension and 2 months of right-sided rhinorrhea underwent surgical repair of a cerebrospinal fluid leak. Topical fluorescein was applied intraoperatively to localize the defect.

RESULTS

At 1- and 3-month follow-ups the patient was without cerebrospinal fluid rhinorrhea and the middle turbinate flap was intact.

CONCLUSION

Topical application of dilute intranasal fluorescein is a feasible and efficient tool for localizing cerebrospinal fluid leaks.

The Umbrella Technique for the Closure of Cerebrospinal Fluid Fistula

ABSTRACT

The diagnosis and management of cerebrospinal fluid (CSF) rhinorrhea remains an important challenge in the field of rhinology. In this study, the authors want to propose a technique for transnasal endoscopic closure of CSF fistulas, tested for the first time on 2 adult fresh cadaveric specimens. The authors think that the use of a device similar to the umbrella device, used to close cardiac atrial defects, may also be valid for the closure of defects at the level of the anterior skull base.

Do Most Patients With a Spontaneous Cerebrospinal Fluid Leak Have Idiopathic Intracranial Hypertension?

BACKGROUND

The association between cerebrospinal fluid (CSF) leaks at the skull base and raised intracranial pressure (ICP) has been reported since the 1960s. It has been suggested that spontaneous CSF leaks might represent a variant of idiopathic intracranial hypertension (IIH). We review the evidence regarding the association between spontaneous CSF leaks and IIH, and the role of ICP in the pathophysiology of nontraumatic skull base defects. We also discuss the management of ICP in the setting of CSF leaks and IIH.

EVIDENCE ACQUISITION

References were identified by searches of PubMed from 1955 to September 2018 with the terms "idiopathic intracranial hypertension" and "cerebrospinal fluid leak." Additional references were identified using the terms "pseudotumor cerebri," "intracranial hypertension," "benign intracranial hypertension," and by hand search of relevant articles.

RESULTS

A CSF leak entails the egress of CSF from the subarachnoid spaces of the skull base into the surrounding cavitary structures. Striking overlaps exist regarding demographic, clinical, and radiological characteristics between IIH patients and those with spontaneous CSF leaks, suggesting that some (if not most) of these patients have IIH. However, determining whether a patient with spontaneous CSF leak may have IIH may be difficult, as signs and symptoms of raised ICP may be obviated by the leak. The pathophysiology is unknown but might stem from progressive erosion of the thin bone of the skull base by persistent pulsatile high CSF pressure. Currently, there is no consensus regarding the management of ICP after spontaneous CSF leak repair when IIH is suspected.

CONCLUSIONS

IIH is becoming more widely recognized as a cause of spontaneous CSF leaks, but the causal relationship remains poorly characterized. Systematic evaluation and follow-up of patients with spontaneous CSF leaks by neuro-ophthalmologists will help clarify the relation between IIH and spontaneous CSF leaks.

Endoscopic endonasal CSF rhinorrhea repair in children: Systematic review with meta-analysis

OBJECTIVES

Cerebrospinal fluid (CSF) rhinorrhea in children is relatively uncommon. Endoscopic repair techniques in adults have become first line for nasal-based CSF leaks, and this meta-analysis looks at the success rates of CSF leak cessation following endoscopic repair in children.

METHODS

Three researchers extracted information involving patient population, surgical technique, outcomes of interest, and study design. A computerized search of MEDLINE, EMBASE and the Cochrane library (January 1990-September 2019) looked for several papers on the subject of CSF leak repair in children using endoscopic technique.

RESULTS

A total of 15 studies met inclusion criteria. Endoscopic repair of CSF rhinorrhea in children shows a pooled weighted success rate of 94% after first attempt. The most common etiology was traumatic followed by congenital. Iatrogenic defects secondary to tumor resection are becoming more common. The high success rate was irrespective of the techniques using.

CONCLUSION

Endoscopic repair techniques have a highly successful closure rate for children presenting with CSF rhinorrhea.

Traumatic Nonmissile Penetrating Transnasal Anterior Skull Base Fracture and Brain Injury with Cerebrospinal Fluid Leak: Intraoperative Leak Detection and an Effective Reconstruction Procedure for a Localized Skull Base Defect Especially After Coronavirus Disease 2019 Outbreak

Background

Cerebrospinal fluid (CSF) leakage after penetrating skull base injury is relatively rare compared with close head injuries involving skull base fractures.

Case Description

We report the case of a 65-year-old man who had presented with epistaxis and serous rhinorrhea. When he had fallen to the ground near his bee boxes, a garden pole had poked into his right nostril. He had instantly removed the pole from his nostril himself. However, immediately after removal of the pole, he had developed nasal bleeding and serous rhinorrhea. He then drove to our emergency room. Computed tomography showed pneumocephalus with a minor cerebral contusion in the left frontal lobe and a penetrating injury in the left anterior skull base. His CSF leakage had not resolve spontaneously within 1 week after the injury with strict bed rest. We repaired the CSF leakage using a fat (adipose tissue)-on-fascia autograft plug and caulked the defect in the anterior skull base with the fat-on-fascia graft (FFG) plug through the left nostril with endoscopic guidance. The CSF rhinorrhea was successfully controlled. Intranasal local application of fluorescein aided in the detection of the direction of flow of the CSF leakage.

Conclusions

Endonasal endoscopic caulking of a skull base defect using an FFG plug can be useful to treat CSF leakage due to the localized skull base defect, especially in the coronavirus disease 2019 pandemic. It is simple, inexpensive, and timesaving. It requires no special skills nor sophisticated instruments that can cause aerosolization, reducing the risk of infection during the surgery.