Intrathecal administration of gadopentetate dimeglumine for MR cisternography of nasoethmoidal CSF fistula

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.

Safety of Intrathecal Administration of Gadolinium-based Contrast Agents: A Systematic Review and Meta-Analysis

Background The use of MR cisternography with intrathecal administration of gadolinium-based contrast agents (GBCAs) is limited by a lack of understanding of the relationship between intrathecal GBCA exposure and dose-related adverse events. Purpose To perform a systematic review to establish an understanding of the dose-response relationship of intrathecal GBCAs and to characterize related adverse events, particularly at higher doses. Materials and Methods Medline, Embase, CINAHL, and Central databases were searched for studies reporting intrathecal GBCA use. Data extraction included studies focused on rates and types of adverse events after intrathecal GBCA exposure. A two-tailed independent sample t test statistic was used to evaluate the relationship between GBCA dose and the presence of serious versus nonserious adverse events. Meta-analysis was used to determine the overall incidence of adverse events. Study quality and publication bias were assessed using the modified Newcastle-Ottawa scale and a funnel plot (effect size measured using Hedges' g followed by the Egger test), respectively. Results Fifty-three studies with a total of 1036 patients were included for analysis. The overall rate of adverse events after intrathecal administration of GBCA was 13% (95% confidence interval [CI]: 9.3%, 18%). Meta-analysis revealed moderate heterogeneity (I² = 62%). Serious adverse event rates could not be determined with meta-analysis. They were reported in 10 studies and were primarily neurologic in nature, with two cases of coma-one resulting in death. Serious adverse events were associated with significantly higher GBCA doses when compared with nonserious adverse events (mean difference, 4.5 mmol; 95% CI: 2.3 mmol, 6.6 mmol; P = .008). For serious adverse events, there was no clear dose-dependent increase in severity above 2.0 mmol. Conclusion Overall, intrathecal administration of GBCAs at doses greater than 1.0 mmol are associated with serious neurotoxic complications with relative clinical safety at lower doses. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Kanal in this issue.

Intrathecal use of gadobutrol for gadolinium-enhanced MR cisternography in the evaluation of patients with otorhinorrhea

PURPOSE

Intrathecal gadolinium-enhanced MR cisternography (IGE-MRC) has a high sensitivity to detect accurate localization of cerebrospinal fluid (CSF) leakage in otorhinorrhea patients. Our purpose in this study was to describe our experience in analyzing clinically suspected CSF leakage by IGE-MRC by using gadobutrol with emphasis on its safety and diagnostic performance.

METHODS

We retrospectively reviewed our imaging and clinical database for the evaluation of patients admitted to our clinic with complaints of otorhinorrhea between 2017 and 2019. Two radiologists evaluated the imaging studies independently. Consensus data was used in the analysis. Medical record review and phone call were used for the follow-up.

RESULTS

Of the 85 patients included in the retrospective analysis, 82 (96.5%) had rhinorrhea and 3 (3.5%) had otorrhea. Overall, 29 patients (34.1% of all patients) underwent operation for repair of the CSF leakage site. Beta-transferrin test was available and positive in 33 patients (38.8%). Five (5.9%) patients complained headaches after the procedure and complaints were resolved with increased water intake. Postprocedurally, 3 patients (3.5%) had vertigo and 1 patient (1.2%) complained nausea but spontaneous regression were observed in a few hours. None of the patients experienced a significant complication or adverse reaction during follow-up period. Sixty-seven patients (78.8%) had medical record and telephone follow-up. Mean follow-up duration with call was 14.2 months.

CONCLUSION

IGE-MRC is a minimally invasive and highly sensitive imaging technique. The current results during our follow-up demonstrate the relative safety and feasibility of IGE-MRC by using gadobutrol to evaluate CSF leakage.

Detection of Cerebrospinal Fluid Leaks: Is There a Radiologic Standard of Care? A Systematic Review

INTRODUCTION

Diagnosis of cerebrospinal fluid (CSF) leaks traditionally involves laboratory testing of markers and appropriate imaging. Surgical localization can be difficult, and the inability to accurately localize skull base defects leads to increased rates of repair failure and complications. Many imaging techniques localizing and identifying CSF leaks have been proposed. Comparisons of current and investigational imaging techniques used to localize CSF leaks are reviewed.

METHODS

A comprehensive and systematic search through PubMed, Scopus, and reference lists from relevant articles was completed to identify literature on sensitivities of different imaging methods for localization and detection of CSF leaks. Prospective, retrospective, and case series published since 1995 that addressed imaging techniques for CSF leaks confined to the skull base were included. Sensitivities of each major imaging technique proposed were recorded and analyzed.

RESULTS

In total, 133 studies initially were screened from 2125 studies on preliminary search. Of these, 38 studies were included based on inclusion criteria. Studies were segregated by imaging modality. A total of 1000 patients with CSF leaks subsequently were evaluated.

CONCLUSIONS

Although radionuclide cisternography has been the historical standard, recent imaging techniques have emerged considering the low sensitivity. Computed tomography cisternography with contrast also has low sensitivity, even in active leaks. Although high-resolution computed tomography is commonly the initial study of choice, magnetic resonance imaging methods, particularly 3-dimensional imaging, may prove to be a more sensitive study of choice. Computed tomography/magnetic resonance imaging combination methods may show promise in localizing CSF leaks. Stratifying by status and etiology may be an important determinant. Further studies investigating various imaging techniques for localizing CSF leaks are needed.

Utility of magnetic resonance cisternography with intrathecal gadolinium in detection of cerebrospinal fluid fistula associated with Mondini dysplasia in a patient with recurrent meningitis: Case report and literature review

Background

The intrathecal contrast-enhanced magnetic resonance cisternography (MRC) is a diagnostic method that has been proven effective in selected patients with various disorders of the cerebrospinal system, including the detection of cerebrospinal fluid (CSF) leaks. The Mondini dysplasia is a malformation of the inner ear characterized by an incomplete cochlear development. The cerebrospinal fistula associated with Mondini dysplasia usually occurs in the first 5-10 years.

Case Description

The case of a 34-year-old woman with CSF rhinorrhea and recurrent meningitis associated with CSF fistula into the right inner ear, which was detected by MRC with intrathecal gadolinium, is presented. The computed tomography (CT) cisternography failed to detect the exact location of the leak. The right Mondini dysplasia was identified on CT of the temporal bone. A subtotal right-sided petrosectomy and fistula closure into the bony labyrinth were performed. After the procedure the patient no longer presented meningitis or CSF leak.

Conclusions

The radiological identification of the site of CSF leak through sensitive imaging studies such as MRC with intrathecal gadolinium is crucial for surgical approach.

Intrathecal gadolinium-enhanced MR cisternography in patients with otorhinorrhea: 10-year experience of a tertiary referral center

PURPOSE

Despite a considerable amount of literature that has been published about the use of intrathecal gadolinium-enhanced MR cisternography (IGE-MRC), there is still relatively lack of evidence as to its long-term effects. Our purpose in this study was twofold: firstly, to assess the long-term safety of the IGE-MRC; secondly, to evaluate the diagnostic performance of IGE-MRC for detecting cerebrospinal fluid (CSF) leak in otorhinorrhea patients.

METHODS

We retrospectively reviewed our imaging and clinical database for the patients admitted to our department for the evaluation of their otorhinorrhea between 2008 and 2017. Two radiologists evaluated the imaging studies independently. Consensus data was used in the analysis. Medical record review and phone call were used for the long-term follow-up.

RESULTS

The retrospective review yielded 166 patients. Rhinorrhea was present in 150 (90.4%) patients and otorrhea in 16 (9.6%) patients. Overall, 67 patients (40.5% of all patients) underwent operation for repair of the CSF leak site. Beta-transferrin test was available and positive in 57 (34.3%) patients. Overall sensitivity of IGE-MRC and paranasal high-resolution CT (HRCT) was 89.3 and 72%, respectively. Within the first 24 h after the procedure, none of the patients experienced a significant complication or adverse reaction. Ninety-nine patients (59.6%) had medical record and telephone follow-up. The mean follow-up duration with call was 37.1 months. Three (3%) patients complained about severe headache 3-4 weeks after the procedure.

CONCLUSIONS

IGE-MRC is a minimally invasive and highly sensitive imaging technique. No adverse side effect during our long-term follow-up might strengthen and support the safety of IGE-MRC.

Imaging of Cerebrospinal Fluid Rhinorrhea and Otorrhea

As the obesity epidemic grows in the United States, rhinorrhea and otorrhea from spontaneous cerebrospinal fluid (CSF) leaks secondary to untreated idiopathic intracranial hypertension are increasing in prevalence. CSF rhinorrhea and otorrhea should also be carefully evaluated in posttraumatic and postsurgical settings, because untreated CSF leaks often have serious consequences. The work-up, diagnosis, and characterization of a CSF leak can be complex, often requiring a multimodality approach to optimize surgical planning. This article reviews the causes of CSF leaks, describes the methodology used to work up a suspected leak, and discusses the challenges of making an accurate diagnosis.

Cerebrospinal fluid rhinorrhea: evaluation with 3D-SPACE sequence and management with navigation-assisted endonasal endoscopic surgery

BACKGROUND

This study aimed to assess the efficacy of MR images with three-dimensional sampling perfection with application optimised contrast using different flip-angle evolution (3D-SPACE) sequence for detecting cerebrospinal fluid (CSF) rhinorrhea and image-guided surgery for the management of CSF rhinorrhea.

MATERIALS AND METHODS

This study included 45 consecutive patients with suspected CSF rhinorrhea from 2010 to 2015. Patients underwent preoperative MRI scan including 3D-SPACE and conventional T2-weighted (T2W) protocol. Two-blinded neuroradiologists determined the presence and location of CSF leakage. Imaging results were compared with surgical findings and/or β-2 transferrin testing. Intraoperative navigation was used during endonasal endoscopic surgery for repairing CSF rhinorrhea.

RESULTS

3D-SPACE sequence correctly described 27 cases (93.1%) and conventional T2W sequence described only 20 (69.0%) of the total 29 patients with truly positive CSF leakage. The sensitivity, specificity, positive predictive value and negative predictive value for detecting CSF leakages were 93.1%, 87.5%, 93.1%, and 87.5% for 3D-SPACE, and 69.0%, 81.3%, 87.0% and 59.1% for T2W, respectively. To repair the leakage, 3D-SPACE image-guided navigation was used to locate the CSF leakage sites intraoperatively. Only two CSF leakage sites proved by surgery were missed by navigation. Successful endoscopic repairs were achieved in 25 of 26 (96.2%) patients during the first attempt. During the follow-up, there were no major postoperative complications or recurrences encountered.

CONCLUSION

MR imaging with 3D-SPACE sequence is an effective and reliable method with higher sensitivity and specificity than T2W for detecting CSF leakage. Intraoperative 3D-SPACE image-guided navigation is helpful in locating the sites of the CSF leakage during endonasal endoscopic surgery.

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

BACKGROUND

Diagnostic strategies employed for cases of cerebrospinal fluid (CSF) rhinorrhea vary widely due to limited evidence-based guidance.

METHODS

A systematic review of the literature was performed using PubMed, EMBASE, and Cochrane databases from January 1990 through September 2014, to examine 9 diagnostic and localization modalities for CSF rhinorrhea. Benefit-harm assessments, value judgments and recommendations were made based on the available evidence. Study exclusion criteria were language other than English, pre-1990 studies, case reports, and nonrhinologic leak. All authors agreed on recommendations through an iterative process.

RESULTS

We reviewed 68 studies examining 9 practices pertinent to the diagnosis of CSF rhinorrhea, with a highest aggregate grade of evidence of C. The literature does not support the use of the ring sign, glucose testing, radionuclide cisternography (RNC), or computed tomography cisternography (CTC) for identification of CSF leak. Beta-2 transferrin is the most reliable confirmatory test for CSF leak. High-resolution CT (HRCT) is then recommended as the first-line study for localization. Magnetic resonance cisternography (MRC) should be used for CSF leak identification as a second line for each of these if beta-2 transferrin is not available or if HRCT is ambiguous. Intrathecal fluorescein (IF) may also be of benefit in certain clinical scenarios.

CONCLUSION

Despite relatively low levels of evidence, recommendations for the diagnosis and management of CSF rhinorrhea can be made based on the current literature. Higher-level studies are needed to better determine optimal diagnostic and clinical management approaches.

T2-weighted vs. intrathecal contrast-enhanced MR cisternography in the evaluation of CSF rhinorrhea

BACKGROUND

Endoscopic surgical approach is being more widely used in the treatment of cerebrospinal fluid (CSF) rhinorrhea. Accurate localization of CSF fistulas prior to surgery is essential in increasing the success of dural repair and in decreasing negative or recurrent explorations.

PURPOSE

To evaluate and compare intrathecal contrast medium-enhanced magnetic resonance cisternography (CEMRC) with T2-weighted MR cisternography (T2MRC) in identifying the presence and site of CSF rhinorrhea.

MATERIAL AND METHODS

Sixty patients with suspected CSF rhinorrhea underwent MR cisternography including intrathecally enhanced fat-suppressed T1WI in three orthogonal planes and T2WI in the coronal plane. Both set of images were reviewed by two blinded radiologists for the presence and location of CSF leakage. Imaging data were compared with surgical findings and/or beta-2 transferrin testing.

RESULTS

With surgery proven CSF leakage in 20 instances as reference, CEMRC detected 18 (90%), whereas T2MRC reported only 13 (65%) correctly. Overall, sensitivity, specificity, positive predictive value, and negative predictive value in detecting CSF fistulas were 92%, 80%, 76%, and 93% for CEMRC, and 56%, 77%, 64%, and 71% for T2MRC, respectively.

CONCLUSION

The minimally invasive CEMRC is an effective method with higher sensitivity and specificity than T2MRC in the evaluation of CSF fistulas.

Spontaneous cerebrospinal fluid rhinorrhoea: computed tomography and magnetic resonance imaging findings

Spontaneous cerebrospinal fluid rhinorrhoea is a rare clinical entity. The accurate localisation of the leakage site is essential for surgical planning. Imaging techniques such as high-resolution computed tomography (CT), CT cisternography and magnetic resonance cisternography in variable combinations are performed for this purpose. This pictorial essay aims to present the spectrum of imaging findings in cases of spontaneous cerebrospinal fluid rhinorrhoea, which may be useful for radiologists in the determination of the site of cerebrospinal fluid leakage.

Comparison of CT and MRI in diagnosis of cerebrospinal leak induced by multiple fractures of skull base

Background

Multiple basilar skull fracture and cerebrospinal leak are common complications of traumatic brain injury, which required a surgical repair. But due to the complexity of basilar skull fracture after severe trauma, preoperatively an exact radiological location is always difficult. Multi-row spiral CT and MRI are currently widely applied in the clinical diagnosis. The present study was performed to compare the accuracy of cisternography by multi-row spiral CT and MRI in the diagnosis of cerebrospinal leak.

Methods

A total of 23 patients with multiple basilar skull fracture after traumatic brain injury were included. The radiological and surgical data were retrospectively analyzed. 64-row CT (mm/row) scan and three-dimensional reconstruction were performed in 12 patients, while MR plain scan and cisternography were performed in another 11 patients. The location of cerebrospinal leak was diagnosed by 2 experienced physicians majoring neurological radiology. Surgery was performed in all patients. The cerebrospinal leak location was confirmed and repaired during surgery. The result was considered as accurate when cerebrospinal leak was absent after surgery.

Results

According to the surgical exploration, the preoperative diagnosis of the active cerebrospinal leak location was accurate in 9 out of 12 patients with CT scan. The location could not be confirmed by CT because of multiple fractures in 2 patients and the missed diagnosis occurred in 1 patient. The preoperative diagnosis was accurate in 10 out of 11 patients with MRI examination.

Conclusions

MRI cisternography is more advanced than multi-row CT scan in multiple basilar skull fracture. The combination of the two examinations may increase the diagnostic ratio of active cerebrospinal leak.

The contribution of 3D-CISS and contrast-enhanced MR cisternography in detecting cerebrospinal fluid leak in patients with rhinorrhoea

The aim of this prospective study was to evaluate the value of unenhanced (three-dimensional constructive interference in steady state (3D-CISS)) and contrast-enhanced MR cisternography (CE-MRC) in detecting the localisation of cerebrospinal fluid (CSF) leak in patients with rhinorrhoea. 17 patients with active or suspected CSF rhinorrhoea were included in the study. 3D-CISS sequences in coronal and sagittal planes and fat-suppressed T1-weighted spin-echo sequences in three planes before and after intrathecal contrast media administration were obtained. Images were obtained of the cribriform plate and sphenoid sinus. In addition, high-resolution CT (HRCT) was performed in order to evaluate the bony elements. The leak was present in 9/17 patients with 3D-CISS and 10/17 patients with CE-MRC. The leak from the cribriform plate to the nasal cavity in six patients and from the sphenoid sinus in four patients was nicely shown by CE-MRC. Eight of those patients were surgically treated, but spontaneous regression of the symptoms in two precluded any intervention. The leak localisations shown with CE-MRC were fully compatible with surgical results. The sensitivities of HRCT, 3D-CISS and CE-MRC for showing CSF leakage were 88%, 76% and 100%, respectively. In conclusion, 3D-CISS is a non-invasive and reliable technique, and should be the first-choice method to localise CSF leak. CE-MRC is helpful in conditions when there is no leak or in complicated cases with a positive beta2-transferrin measurement.

Phase-contrast cine MRI versus MR cisternography on the evaluation of the communication between intraventricular arachnoid cysts and neighbouring cerebrospinal fluid spaces

INTRODUCTION

The objective of this study was to evaluate the role of phase-contrast cine magnetic resonance imaging (PC-MRI) in detecting possible communications between intraventricular arachnoid cysts (IV-ACs) and cerebrospinal fluid (CSF) spaces based on MR cisternography (MRC) comparison.

MATERIALS AND METHODS

Twenty-one patients with IV-AC were examined by PC-MRI and MRC. In order to determine the communication of IVAC with its neighbouring CSF spaces, PC-MRI was employed. The communication of IV-ACs with the ventricular system was examined on at least two anatomic planes. Precontrast images and PC-MRI were followed by the intrathecal administration of 0.5-1 ml gadopentetate dimeglumine. Early and delayed MRC were then carried out. Results of PC-MRI were compared with findings of MRC (McNemar's test).

RESULTS

In seven IV-ACs, no communication was detected by PC-MRI. In 14 IVACs, a pulsatile CSF flow into the IV-ACs was observed. All the IV-ACs, which have been determined as non-communicating (NC) on the PC-MRI, showed NC character on MRC as well. Six cases suggesting a communication on PC-MRI showed no communication on MRC. MRC revealed eight communicating (38%) and 13 NC (62%) IV-ACs among a total of 21 cases. The sensitivity and specificity of PC-MRI imaging in demonstrating the communication between the IV-ACs and the CSF were 100% and 54%, respectively.

CONCLUSION

PC-MRI is an effective method for evaluating NC IV-ACs. In order to decide about the management of IV-ACs, which are communicating according to the PC-MRI, the results should be confirmed with MRC if suspected jet flow is depicted.

MR-Cisternography with T2-Weighted Single-Shot Fast Spin Echo Sequence in the Diagnosis of a Spontaneous CSF Fistula of the Sphenoid Sinus Causing Massive Pneumocephalus

A spontaneous CSF fistula of the sphenoid sinus was preoperatively diagnosed in a young woman presenting with massive pneumocephalus and rhinorrhea. Diagnosis was established by MR cisternography using a heavily T2-weighted 3D single-shot FSE sequence with half-Fourier analysis (3D-EXPRESS(®)), originally developed for imaging the inner ear. While unenhanced CT failed to detect the site of the fistula, MR permitted complete evaluation of the sellar/sphenoid region and tracked the CSF signal down to the nasal cavity.

Localization of cerebrospinal fluid leaks by gadolinium-enhanced magnetic resonance cisternography: a 5-year single-center experience

OBJECTIVE

Intrathecal gadolinium (Gd)-enhanced magnetic resonance (MR) cisternography is a newly introduced imaging method. Two main objectives of this study were to investigate the sensitivity of Gd-enhanced MR cisternography for presurgical localization of cerebrospinal fluid (CSF) leaks in patients with CSF rhinorrhea and to study the potential long-term adverse effects of intrathecal Gd application.

METHODS

Fifty-one patients (19 women; mean age, 36.2 yr) with CSF rhinorrhea were included in the study. A total of 0.5 ml of Gd was injected into the lumbar subarachnoid space. T1-weighted MR cisternographic images were obtained to detect CSF leakage. The patient's neurological states and vital signs were recorded for the first 24 hours after the procedure. Neurological evaluations were repeated 1, 3, and 12 months after the procedure. The patients were followed for at least 3 years with annual neurological examinations.

RESULTS

Gd-enhanced MR cisternography demonstrated CSF leaks in 43 of the 51 patients. The sensitivity of Gd-enhanced MR cisternography for localization of CSF leaks was 84%. Forty-four patients underwent surgery to repair dural tears. Surgical findings confirmed the results of Gd-enhanced cisternography in 43 of the 44 patients who underwent surgery (98%). Eight patients with negative Gd-enhanced MR cisternography had no active rhinorrhea at the time of procedure, and seven of them did not need surgery. None of the patients developed an acute adverse reaction that could be attributed to the procedure. None of the patients developed any neurological symptoms or signs caused by intrathecal Gd injection during a mean follow-up period of 4.12 years.

CONCLUSION

Gd-enhanced MR cisternography is a sensitive and safe imaging method for detection of CSF leaks in patients with rhinorrhea.

Intrathecal gadolinium-enhanced magnetic resonance cisternography in cerebrospinal fluid rhinorrhea: road ahead?

Accurate localization of cerebrospinal fluid (CSF) fistula in a patient with CSF rhinorrhea is challenging and often involves multiple imaging studies with associated expense and patient discomfort. Intrathecal contrast-enhanced computed tomography (CT) and unenhanced magnetic resonance (MR) cisternography using constructive interference in steady state (CISS-3D) sequences are currently being used in attempt to localize the leakage site but with varying degrees of success. Our purpose is to evaluate the utility of intrathecal gadolinium-enhanced MR cisternography (GdMRC) in patients with CSF rhinorrhea. Ten consecutive patients of CSF rhinorrhea (five spontaneous, four post-traumatic, and one post-operative) were evaluated with GdMRC. Nine of the patients underwent intrathecal contrast CT and CISS-3D examinations in addition. Each of studies was reviewed independently by three neuroradiologists blinded to results of other modalities. Surgery was planned after consensus and surgical correlation obtained in nine cases. The fistulous site was clearly demonstrated by using GdMRC in eight patients, CISS-3D in six, and intrathecal CT in three patients. The site of leakage was confirmed surgically in all the patients. One patient was found to be false negative both by intrathecal CT and GdMRC, and in one patient no fistulous site was demonstrated by any of the modalities and surgery was not offered. No adverse reaction was seen in any of the patients. GdMRC is a novel method of confirmation and localization of CSF fistula with potential for routine clinical application. Diagnosis and localization of fistulous site is better demonstrated due to its high-contrast resolution, absence of bony artifacts, and direct multi-planar imaging.