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

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.

[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.

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.

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.

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.

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.

Imaging of the Spontaneous Low Cerebrospinal Fluid Pressure Headache: A Review

Spontaneous intracranial hypotension (SIH) is a significant cause of chronic, postural headaches. Spontaneous intracranial hypotension is generally believed to be associated with cerebrospinal fluid (CSF) leaks, and these leaks can be posttraumatic, iatrogenic, or idiopathic in origin. An integral part of the management of patients with this condition consists of localizing and stopping the leaks. Radiologists play a central role in the workup of this condition detecting leaks using computed tomography, magnetic resonance imaging, or nuclear imaging. In this article, we briefly review SIH and the various imaging modalities, which can be used to identify and localize a spontaneous CSF leak.

Economic implications of localization strategies for cerebrospinal fluid rhinorrhea

BACKGROUND

The direct costs associated with different diagnostic algorithms to localize cerebrospinal fluid (CSF) rhinorrhea have not been described.

METHODS

A decision-tree analysis of imaging modalities used to localize CSF rhinorrhea was performed to compare associated direct costs. The primary outcome was cost, which was determined based on reimbursement data published by the Centers for Medicare and Medicaid Services in 2018. The model was parameterized after a literature review of published studies was performed from 1990 to 2018 to estimate the sensitivity CSF rhinorrhea localization of the following radiographic modalities: high-resolution computed tomography (HRCT), magnetic resonance cisternography (MRC), and CT cisternography (CTC). In addition to base case analysis, 1-way sensitivity analyses were also performed to evaluate the robustness of results to changes in model parameters.

RESULTS

Among patients with a high suspicion for CSF rhinorrhea, use of HRCT followed by exploration in the operating room if preliminary HRCT was negative was found to be the optimal localization modality from a cost perspective ($172.25). The next least costly algorithm was HRCT followed by MRC ($294.10). Imaging algorithms beginning with CTC were the next least costly modality ($727.37). Sensitivity analyses generally supported HRCT to be the optimal initial radiographic strategy over a wide range of parameter values.

CONCLUSION

This work advocates HRCT as first-line modality to localize CSF rhinorrhea from a cost perspective. Although algorithms beginning with MRC were on average $35 more expensive than those starting with CTC, associated risks of CTC were not modeled and may play a role in decision making.

[A modern approach to the diagnosis of nasal liquorrhea]

Nasal liquorrhea is cerebrospinal fluid leakage from cerebrospinal fluid spaces of the cerebral cavity into the nasal cavity or paranasal sinuses due to congenital or acquired abnormalities of the skull base bones and meninges of various etiologies. The severity of liquorrhea varies from hidden manifestations to profuse leakage of cerebrospinal fluid from the nasal cavity. The diagnosis of overt nasal liquorrhea is not problematic, but the diagnosis of latent liquorrhea is a challenge. In this case, the disease leads to potentially fatal complications, such as meningitis (the risk amounts to 10-37%), pneumocephaly, pneumonia, etc. These peculiarites give rise to two main tasks: early diagnosis confirming liquorrhea and accurate identification of the CSF fistula location when planning further surgical management.

PURPOSE

The study purpose was to review and comparatively analyze all modern methods of diagnosing nasal liquorrhea as well as to substantiate the most effective and promising approaches and algorithms.

MATERIAL AND METHODS

The study included papers in English and Russian found in the Pubmed database and related to the diagnosis of basal liquorrhea of different etiology and localization.

RESULTS

This review demonstrates that diagnostic tests vary widely in sensitivity, specificity, accuracy, invasiveness, and cost. Given all the criteria, detection of beta-2 transferrin or beta-trace protein is the best method for confirming nasal liquorrhea, and high-resolution computed tomography is the best technique for localization of the abnormality.

CONCLUSION

Based on the review, we suggest a diagnostic algorithm for nasal liquorrhea. However, the evidence presented in this review is unfortunately not very reliable, which indicates the existing need for more accurate studies.

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.

Cerebrospinal fluid rhinorrhea and otorrhea: A multimodality imaging approach

Cerebrospinal fluid (CSF) leaks are extracranial egress of CSF into the adjacent paranasal sinus or tympanomastoid cavity due to an osteodural defect involving skull base. It can be due to a multitude of causes including accidental or iatrogenic trauma, congenital malformations and spontaneous leaks. Accurate localization of the site of the leak, underlying causes and appropriate therapy is necessary to avoid associated complications. In this paper relevant anatomy, clinical diagnosis, imaging modalities and associated findings are discussed along with a brief mention about management.

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.

Role of intraoperative dynamic magnetic resonance myelogram in management of giant dorsolumbar spinal extradural arachnoid cyst: case report

Giant dorsolumbar spinal arachnoid cysts are a complex, poorly understood, and difficult to manage clinical entity. Traditional CT myelography is technically difficult to use in these cases to detect the site of leakage preoperatively. The authors report a novel technique for detecting the site of the leak by using sequential, dynamic intraoperative MR myelography. To the authors' knowledge, there is no other similar report in the literature.

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.

The value of 3D-FIESTA MRI in detecting non-iatrogenic cerebrospinal fluid rhinorrhoea: correlations with endoscopic endonasal surgery

BACKGROUND

In this study, we investigated the value of three-dimensional (3D) fast-imaging employing steady-state acquisition (FIESTA) magnetic resonance imaging (MRI) in detecting non-iatrogenic cerebrospinal fluid (CSF) rhinorrhoea and compared it with regular MRI and 3D magnetisation prepared rapid acquisition gradient echo (MPRAGE) MRI sequences, as well as high-resolution computed tomography (HRCT) imaging. We also present the endoscopic experiences of such cases.

METHOD

From June 2011 to Feb 2016, 17 patients with non-iatrogenic cerebrospinal fluid rhinorrhoea were included. Seven patients had spontaneous rhinorrhoea, three patients had invasive tumours, and the remaining patients had traumatic aetiologies. All the patients underwent HRCT, regular MRI sequence imaging, 3D-MPRAGE MRI sequence imaging and 3D-FIESTA MRI sequence imaging for the preoperative evaluations of the leakages. For each patient, the CSF fistula site was confirmed by intraoperative neuronavigation and endoscopic findings. Statistical analyses were performed. All patients underwent endoscopic multilayer repair.

RESULTS

The sensitivities of the HRCT, regular MRI (T1 and T2), 3D-MPRAGE and 3D-FIESTA modalities for identifying CSF leakage were 58.8 %, (11.8 % and 29.4 %), 74.7 %, and 88.2 %, respectively. The origins of the leakages included the cribriform plate (18 %), ethmoidal fovea (23 %), lateral recess of the sphenoid (17 %), sellar floor (12 %), ethmoidal roof (12 %), junction of the fovea and cribriform plate (6 %) and the junction of sellar and sphenoidal planum (6 %). Two patients required repair. The first was under local anaesthesia when the nasal packing was removed, and the second underwent repair at the same site a half-year later due to hydrocephalus. Lumbar drainage was performed in all cases. No major complications were encountered.

CONCLUSIONS

The endoscopic endonasal approach is safe and effective for the treatment of CSF rhinorrhoea. The 3D-FIESTA MR modality is superior to 3D-MPRAGE MR and HRCT in the depiction of the CSF fistula site. Due to its non-invasive and reliable properties, 3D-FIESTA MR should be the preferred preoperative examination for the patients with non-iatrogenic CSF rhinorrhoea.

Management of CSF leak in base of skull fractures in adults

AIMS

CSF leaks are not uncommon after a base of skull fracture. Currently there is no standardised algorithm for the investigation and management of post-traumatic CSF leaks. In this paper we aim to provide an evidence-based framework for managing post-traumatic CSF leaks.

METHODS

We searched the English literature over the past 45 years using CINAHL, EMBASE and MEDLINE for the terms (1) post-traumatic CSF leaks or fistulas, and (2) basilar or base of skull fractures, but excluded papers on post-operative and non-traumatic CSF leaks, and papers on paediatric post- traumatic CSF leaks.

RESULTS

The diagnosis of a base of skull fracture and any resultant CSF leak can be challenging. Therefore a combination of biochemical and radiological studies are needed to optimise the diagnosis of this condition. Post-traumatic CSF leaks are generally treated conservatively, and a majority of them resolve without further surgical management. However for patients who are refractory to such treatments, surgical closure of the CSF fistula is necessary. Surgical obliteration of CSF leaks can be challenging and requires the involvement of multiple surgical specialties such as neurosurgery, otolaryngology, and maxillofacial surgery.

CONCLUSION

Although we have formulated a simple algorithm to aid the investigation and management of post-traumatic CSF leaks, there are still many important unresolved questions requiring further well powered studies to answer.

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.

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

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

Intrathecal gadolinium-enhanced MR cisternography: a comprehensive review

CE-MRC has been in use for the past 15 years and was reported to be a useful method in the evaluation of CSF disorders and hydrocephalus. The use of CE-MRC in conjunction with other MR imaging techniques has been shown to be effective in selected cases for the evaluation of several disorders of cerebrospinal system. CE-MRC has certain advantages over other cisternographic studies with fewer side effects if performed properly. Although intrathecal Gd administration is not widely accepted yet, several recent studies have reported the safety of small-dose intrathecal gadolinium injection. In this review, we describe CE-MRC and review recent applications in several clinical conditions.

High resolution MR for evaluation of lower urogenital tract malformations in infants and children: feasibility and preliminary experiences

INTRODUCTION

This retrospective study aimed to assess the value of supplementing heavily T2-weighted, high resolution MR-imaging for detailed anatomic assessment in paediatric lower urogenital tract (UGT) malformations.

PATIENTS/METHODS

Sixteen patients (6 male and 10 female, median age=1.8 years, range=0-9 years) with suspected malformations of the lower UGT who were retrospectively identified from the PACS underwent a clinically indicated standard MR-urography study. In order to facilitate a better anatomic assessment of questioned specific lower UGT structures, an additional three-dimensional Constructive Interference in Steady State-sequence (3D-CISS) had been acquired in these patients. The final diagnosis was established by all imaging results and surgical or laprascopic findings. The findings from the CISS-sequence were compared to the results from standard MR-urography for complementary anatomic information and conspicuity.

RESULTS

Diagnostic 3D-CISS image quality was achieved in all patients. The 3D-CISS confirmed an ectopic ureteral insertion in six patients and reliably excluded ectopic insertion in 10 patients, whereas conventional MR-urography showed an ectopic insertion of the ureter in one case. In six patients with retrovesical complex formations (suspicious for an ectopic cystic renal bud or a cystic genital structure) the 3D-CISS showed increased conspicuity scores for image quality.

CONCLUSION

The additional 3D-CISS-sequence increases the diagnostic yield in the pelvis in children with complex malformations of the lower UGT such as ectopic ureteral insertion or suspected cystic renal or genital malformations at only minimal additional time, compared to standard MR-urography.

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.

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.