Intrathecal gadolinium-enhanced MR cisternography in the evaluation of CSF leakage

Prospective Safety Study of Intrathecal Gadobutrol in Different Doses

BACKGROUND AND PURPOSE

In our clinical practice, we increasingly use intrathecal contrast-enhanced glymphatic MR imaging to assess CSF disturbances. However, because intrathecal MR imaging contrast agents such as gadobutrol (Gadovist; 1.0 mmol/mL) are used off-label, a thorough understanding of the safety profile is required.

MATERIALS AND METHODS

We performed a prospective safety study from August 2020 to June 2022 of intrathecal gadobutrol, including consecutive patients who received either 0.50, 0.25, or 0.10 mmol. Serious and nonserious adverse events were recorded systematically at 1-3 days, 4 weeks, and >6 months after the intrathecal administration.

RESULTS

The study included 196 patients who received intrathecal gadobutrol, including patients assessed for idiopathic normal pressure hydrocephalus (iNPH, n = 144) or patients examined for other CSF disorders (non-iNPH cohort; n = 52). The intrathecal gadobutrol doses were either 0.50 mmol (n = 56), 0.25 mmol (n = 111), or 0.10 mmol (n = 29). No serious adverse events were observed. Nonserious adverse events on days 1-3 after intrathecal gadobutrol were, to some degree, dose-dependent but mild-to-moderate, including severe headache, nausea, and/or dizziness in 6/196 (6.3%) patients, and they were more common in the non-iNPH than in the iNPH cohort. At 4 weeks, none reported severe nonserious adverse events, and 9/179 (5.0%) patients had mild-to-moderate symptoms. After >6 months, 2 patients reported mild headache.

CONCLUSIONS

The present study adds to the accumulating evidence that intrathecal gadobutrol in doses up to 0.50 is safe.

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.

Cerebrospinal fluid leak management in anterior basal skull fractures secondary to head trauma

OBJECTIVE

To summarize the presentation, diagnosis, and management of cerebrospinal fluid (CSF) leaks in the setting of traumatic anterior skull base fracture.

METHODS

Wide literature research has been performed as well as the authors' own clinical experience has been summarized.

RESULTS

Articles from the most recent 30 years have been reviewed and a typical case of our own has been presented. Based on the most updated evidence, a treatment algorithm for CSF leaks has been proposed.

CONCLUSION

Anterior skull base fracture accounts for about 4% of all head injuries and CSF leaks is a complication that commonly presents with clear fluid emanating from the nasal passage. A positive beta-2-transferrin study is highly specific for diagnosis, while thin-slice CT scanning and MRI cisternography are also useful tools. The majority of the CSF leaks tend to be resolved spontaneously, and conservative management is attempted first with or without the augmentation of a lumbar drain. Surgical management mainly includes open surgery and endoscopic surgery, which have their own pros and cons.

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.

Imaging After Sinonasal Surgery

Posttreatment imaging evaluation of sinuses encompasses a wide gamut of procedures, ranging from endoscopic procedures for sinonasal inflammatory diseases to markedly radical surgeries for malignant neoplasms (with or without reconstructions), as well as providing access for surgeries involving the anterior and central skull base. Advances in both techniques and devices have expanded the use of endoscopic approaches in managing both benign and malignant lesions, in addition to being the primary surgical method for treating all medically refractive sinonasal inflammatory disorders. Familiarity with the complex anatomy in the sinonasal region and knowledge of the various procedures is indispensable in interpreting these imaging studies.

Idiopathic intracranial hypertension - a wider spectrum than headaches and blurred vision

BACKGROUND

The purpose of this study was to analyse less known clinical scenarios associated with idiopathic intracranial hypertension.

METHODS

The study involved analysis of magnetic resonance imaging signs of idiopathic intracranial hypertension in patients with spontaneous rhinoliquorrhoea (n = 7), in patients with temporal lobe epilepsy and surgically treated antero-inferior temporal lobe meningo-encephaloceles (n = 15), and in patients who developed clinical signs of idiopathic intracranial hypertension following the treatment of spontaneous intracranial hypotension (n = 7).

RESULTS

Three of six patients with spontaneous rhinoliquorrhoea and six of 15 operated patients with temporal lobe epilepsy due to temporal lobe meningo-encephaloceles showed magnetic resonance imaging signs of idiopathic intracranial hypertension and had a body mass index >30 kg/m². Rebound high pressure headaches and sings of idiopathic intracranial hypertension occurred in seven of 44 surgically treated spontaneous intracranial hypotension patients.

CONCLUSIONS

Magnetic resonance imaging findings should guide the clinician to consider (idiopathic) intracranial hypertension when patients develop spontaneous rhinoliquorrhoea, temporal lobe epilepsy secondary to temporal lobe meningoencephaloceles or high pressure headaches in spontaneous intracranial hypotension. Whether idiopathic intracranial hypertension must be regarded as a differential diagnosis or as a cause, or whether there are common pathophysiological pathways that lead to signs of idiopathic intracranial hypertension in this wider spectrum of disease is the focus of further study.

Special MRI Techniques to Suss out Spontaneous Cerebrospinal Fluid Leaks

Anterior skull base cerebrospinal fluid (CSF) fistulas result from skull base osteodural defects, allowing subarachnoid space CSF to escape into pneumatized cavities such as the paranasal sinuses and nasal fossa. Precise localization, characterization, and effective treatment of CSF leaks is essential to prevent meningitis, treatment failure, or recurrence. Advances in magnetic resonance imaging have improved radiologists' ability to localize and characterize anterior skull base CSF fistulas. This article reviews new imaging techniques enabling diagnostic location of CSF fistulas, with an emphasis on magnetic resonance imaging-based techniques.

Management of anterior fossa cephaloceles

Skull base cephaloceles (SBCs) are defined as herniation of intracranial content through the skull base and are classified based on composition, etiology, and topographic location. Anterior SBCs frequently protrude in the sinonasal cavity, and consequently are at potential risk of infection. Therefore, the current recommendation is to treat SBCs with the primary intent of preventing meningitis, and surgery represents the mainstay of treatment. Anterior SBCs may display a wide spectrum of severity and complexity, and in each case the risks and benefits of surgical approaches are to be carefully weighted based on thorough assessment of symptoms, age, general conditions, location and size of the lesion, as well as expertise of the surgeon. In the last 30 years, the evolution and diffusion of transnasal endoscopic surgery have substantially changed the surgical management of the majority of SBC. In the past, they were treated exclusively with open transcranial approaches that may be burdened by relevant morbidity and risk for severe complications. The transnasal endoscopic corridor now provides easy access to the lesion and different reconstructive strategies using endonasal pedicled flaps, without any external incision, cranioplasty or brain manipulation. However, there are still scenarios in which an exclusive transnasal endoscopic route is contraindicated. The aim of the present review was to provide an overview on the comprehensive management of anterior SBC, with a particular focus on lesions suitable for endoscopic surgery. Furthermore, special aspects of SBC management in children and adults will be highlighted.

High-Resolution Gadolinium-Enhanced MR Cisternography Using Compressed-Sensing T1 SPACE Technique for Detection of Intracranial CSF Leaks

In patients with CSF rhinorrhea, accurate identification of the CSF leakage site is crucial for surgical planning. We describe the application of a novel gadolinium-enhanced high-resolution 3D compressed-sensing T1 SPACE technique for MR cisternography and compare findings with CT cisternography and intraoperative results. In our pilot experience with 7 patients, precise detection of CSF leaks was feasible using compressed-sensing T1 SPACE, which appeared to be superior to CT cisternography.

Off-label intrathecal use of gadobutrol: safety study and comparison of administration protocols

Purpose

Magnetic resonance imaging (MRI) contrast agents have been used off-label for diagnosis of cerebrospinal fluid (CSF) leaks and lately also for assessment of the glymphatic system and meningeal lymphatic drainage. The purpose of this study was to further evaluate the short- and long-term safety profile of intrathecal MRI contrast agents.

Methods

In this prospective study, we compared the safety profile of different administration protocols of intrathecal gadobutrol (Gadovist^TM; 1.0 mmol/ml). Gadobutrol was administered intrathecal in a dose of 0.5 mmol, with or without iodixanol (Visipaque^TM 270 mg I/ml; 3 ml). In addition, a subgroup was given intrathecal gadobutrol in a dose of 0.25 mmol. Adverse events were assessed at 1 to 3 days, 4 weeks, and after 12 months.

Results

Among the 149 patients, no serious adverse events were seen in patients without history of prior adverse events. The combination of gadobutrol with iodixanol did not increase the occurrence of non-serious adverse events after days 1–3. Intrathecal gadobutrol in a dose of 0.25 mmol caused less severity of nausea, as compared with the dose of 0.5 mmol. The clinical diagnosis was the major determinant for occurrence of non-serious adverse events after intrathecal gadobutrol.

Conclusion

This prospective study showed that intrathecal administration of gadobutrol in a dose of 0.5 mmol is safe. Non-serious adverse events were to a lesser degree affected by the administration protocols, though preliminary data are given that side effects of intrathecal gadobutrol are dose-dependent.

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.

Spinal Cerebrospinal Fluid Leakage in Spontaneous Intracranial Hypotension: An Intrathecal Gadolinium Enhanced MR-Myelography Study

Objectives:

In the present study, the authors presented the intrathecal gadolinium enhanced MR-myelography findings of patients with spontaneous intracranial hypotension.

Materials and Methods:

Intrathecal gadolinium enhanced MR-myelography (Gd-MR-myelography) examinations between October 2012 and September 2018 in patients having clinical and radiological findings of spontaneous intracranial hypotension were evaluated retrospectively. Sites and types of contrast leakages in 20 patients who met inclusion criteria were reviewed. All patients had undergone T1-fat suppressed sagittal images of cervical, thoracic and lumbar region after the off label intrathecal injection of 1 ml gadolinium-based contrast agent.

Results:

Patients (18 female, 2 male) are aged between 23 and 62 years-old (mean age: 41.1). Cerebrospinal fluid (CSF) leakages were cervical in 6 patients, thoracic in 5 patients, lumbar in 5 patients. One patient had leakage in multiple levels on both cervical and thoracic region and another patient on both cervical-thoracic and lumbar regions. No patients had adverse effects related to intrathecal injection of gadolinium.

Conclusions:

Gd-MR-myelography is effective imaging modality to reveal spinal CSF leakages in patients with spontaneous intracranial hypotension.

MRI myelography for diagnosis and targeted blood patching of multilevel thoracic spine CSF leaks: Report of 2 cases

In patients with occult cerebrospinal fluid (CSF) leaks or CSF leak syndrome, orthostatic headaches are a common presenting symptom. Although computed tomography (CT) myelography has historically been the gold standard for diagnosis with radioisotope cisternography as a diagnostic alternative, magnetic resonance imaging (MRI) myelography using intrathecal gadolinium has reported sensitivity of 80%-87%. Two patients with spontaneous orthostatic headaches lasting for several days were diagnosed with CSF leaks at multiple thoracic segments using MRI myelogram with intrathecal gadolinium (Gadavist, Bayer, Whippany, NJ). This allowed for subsequent targeted treatment with CT fluoroscopy guidance, resulting in therapeutic responses within 1-2 treatment with targeted blood patching. Although intrathecal gadolinium is an off-label use, the superior contrast resolution and lack of radiation exposure makes MRI myelography an excellent imaging modality for diagnosing CSF leak, targeting treatment, and monitoring outcomes compared to CT myelography and radioisotope cisternography.

Intrathecal Use of Gadobutrol for Glymphatic MR Imaging: Prospective Safety Study of 100 Patients

BACKGROUND AND PURPOSE

Intrathecal contrast-enhanced glymphatic MR imaging has shown promise in assessing glymphatic function in patients with dementia. The purpose of this study was to determine the safety profile and feasibility of this new MR imaging technique.

MATERIALS AND METHODS

A prospective safety and feasibility study was performed in 100 consecutive patients (58 women and 42 men, 51 ± 19 years of age) undergoing glymphatic MR imaging from September 2015 to August 2018. Short- and long-term serious and nonserious adverse events were registered clinically and by interview after intrathecal administration of 0.5 mL of gadobutrol (1.0 mmol/mL) along with 3 mL of iodixanol (270 mg I/mL). Adverse events are presented as numbers and percentages.

RESULTS

One serious adverse event (anaphylaxis) occurred in a patient with known allergy to iodine-containing contrast agents (1%). The main nonserious adverse events during the first 1-3 days after contrast injection included severe headache (28%) and severe nausea (34%), though the frequency depended heavily on the diagnosis. After 4 weeks, adverse events had resolved.

CONCLUSIONS

Intrathecal administration of gadobutrol in conjunction with iodixanol for glymphatic MR imaging is safe and feasible. We cannot conclude whether short-duration symptoms such as headache and nausea were caused by gadobutrol, iodixanol, the lumbar puncture, or the diagnosis. The safety profile closely resembles that of iodixanol alone.

Meningitis for Streptococcus salivarius Secondary to Paradoxical Cerebrospinal Fluid Rhinorrhea as a Complication of Retrosigmoid Approach

Rhinorrhea secondary to a retrosigmoid approach is rare, but when it manifests, it is due to a paradoxical cerebrospinal fluid (CSF) leak, as a result of the communication between the mastoid cells, middle ear, and eustachian tube, which finally ends on the release of CSF through the nasopharynx. Abnormal communications increases the risk of infections, not only at the surgical site but also through an ascending path. Magnetic resonance cisternography (MRC) with intrathecal gadolinium injection through a lumbar puncture not only allows an adequate diagnosis but also helps to establish management plans. Here, we present an eighty-three-year-old female patient, with a history of trigeminal neuralgia, who underwent retrosigmoid approach to perform trigeminal microvascular decompression. After intervention, the patient consulted for rhinorrhea, fever, and headache. Lumbar puncture was performed, resulting on the isolation of Streptococcus salivarius in CSF. Nuclear MRC with intrathecal gadolinium injection was performed, identifying a paradoxical CSF leak. Failure in medical management with conservative treatment ends in surgical reexploration, identifying a bone defect in mastoid cells, which was corrected.

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.

Surgical Management of Sphenoid Sinus Lateral Recess Cerebrospinal Fluid Leaks: A Single Neurosurgical Center Analysis of Endoscopic Endonasal Minimal Transpterygoid Approach

OBJECTIVE

To review the results of sphenoid sinus lateral recess (SSLR) cerebrospinal fluid (CSF) leaks treated with the endoscopic endonasal minimal transpterygoid approach (EEMTPA) and to discuss the surgical technique and outcomes.

METHODS

We performed a retrospective analysis of 13 cases who underwent SSLR CSF leak repair through the EEMTPA in our clinic between September 2008 and December 2017. Demographic and etiological features with reconstruction and surgical outcomes were examined. Mean follow-up time was 6.1 years.

RESULTS

In regard to etiology, the SSLR CSF leaks included 9 patients with spontaneous, 2 patients with traumatic, and 2 with iatrogenic causes. CSF leak was at the left lateral recess in 8 cases and at right lateral recess in 5 cases. Nine patients had empty sella syndrome, and 11 patients had meningoencephaloceles in addition to SSLR CSF leaks. All patients underwent surgery through the EEMTPA, and a multilayer closure with tissue overlay grafts were used for reconstruction. A pedicled nasoseptal flap and/or pedicled middle turbinate flap were applied to the area of the leak in all cases. One patient had a persistent CSF leak and another had recurrence, both of which required revision surgery. Our overall success rate was 100%.

CONCLUSIONS

EEMTPA is a safe and effective method that can be used to treat challenging pathologies at the SSLR, including CSF leaks accompanying meningoencephaloceles. Furthermore, the success rate of EEMTPA for SSLR CSF leaks can be increased by applying endoscopic skull base reconstruction techniques such as the pedicled nasoseptal flap and pedicled middle turbinate flap.

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.

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 Intracranial Pressure Disorders

Intracranial pressure (ICP) is the pressure inside the bony calvarium and can be affected by a variety of processes, such as intracranial masses and edema, obstruction or leakage of cerebrospinal fluid, and obstruction of venous outflow. This review focuses on the imaging of 2 important but less well understood ICP disorders: idiopathic intracranial hypertension and spontaneous intracranial hypotension. Both of these ICP disorders have salient imaging findings that are important to recognize to help prevent their misdiagnosis from other common neurological disorders.

Head and Neck: Skull Base Imaging

There are a myriad of head and neck pathologies that extend from the extracranial to the intracranial compartment, traversing the skull base, and knowledge of the imaging appearance of this pathology is critical to practicing neurosurgeons. This article reviews some of the important inflammatory or acquired head and neck pathology along the skull base, neoplastic skull base lesions, and the intracranial extension of head and neck malignancy. Focus will be on the relevant anatomy, appropriate imaging protocols to evaluate these processes, as well as the differentiating imaging findings on computed tomography and magnetic resonance imaging.

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.

Imaging in Endoscopic Cranial Skull Base and Pituitary Surgery

Endoscopic endonasal approaches have widely accepted techniques for managing benign and malignant processes along the entire ventral skull base with similar or better results compared with open procedures, but with lower rates of complication. Managing pathology affecting the skull base can be challenging because of complex anatomy and the proximity of critical neurovascular structures. Postoperative imaging can be challenging, because of surgical alterations of normal anatomy and the now common use of complex reconstruction techniques. Understanding the normal imaging appearance of skull base reconstruction is important for accurate postoperative interpretation and delineation between normal reconstructive tissue and recurrent neoplasm.

Brain Imaging in Idiopathic Intracranial Hypertension

BACKGROUND

The primary role of brain imaging in idiopathic intracranial hypertension (IIH) is to exclude other pathologies causing intracranial hypertension. However, subtle radiologic findings suggestive of IIH have emerged with modern neuroimaging. This review provides a detailed description of the imaging findings reported in IIH and discusses their possible roles in the pathophysiology and the diagnosis of IIH.

EVIDENCE ACQUISITION

References were identified by searches of PubMed from 1955 to January 2015, with the terms "idiopathic intracranial hypertension," "pseudotumor cerebri," "intracranial hypertension," "benign intracranial hypertension," "magnetic resonance imaging," "magnetic resonance venography," "computed tomography (CT)," "CT venography," "imaging," and "cerebrospinal fluid (CSF) leak." Additional references were identified by hand search of relevant articles. When possible, we extracted the number of patients and control subjects from each study for each radiological finding. When at least 2 studies used the same criteria to define a radiological finding, all patients from these studies were pooled to obtain a mean sensitivity and specificity with 95% confidence interval.

RESULTS

Specific neuroimaging findings may suggest long-standing IIH, including empty sella, flattening of the posterior globes, optic nerve head protrusion, distention of the optic nerve sheaths, tortuosity of the optic nerve, cerebellar tonsillar herniation, meningoceles, CSF leaks, and transverse venous sinus stenosis.

CONCLUSION

Although IIH remains a diagnosis of exclusion, the most recently proposed diagnostic criteria have included neuroimaging findings to suggest IIH when major diagnostic criteria are not fulfilled. However, these findings are not diagnostic of IIH, and their presence is not required for the diagnosis of definite IIH. Their incidental discovery on brain imaging should not prompt invasive procedures, unless other signs of IIH, such as papilledema, are present.

Posttraumatic Temporal Bone Meningocele Presenting as a Cystic Mass in the External Auditory Canal

INTRODUCTION

Temporal bone meningoencephalic herniation may occur in head trauma. It is a rare condition with potentially dangerous complications. Several different routes for temporal bone meningoencephalocele have been proposed.

CLINICAL REPORT

An11-year-old boy with history of head trauma initially presented with a 9-months history of progressive right-sided hearing loss and facial weakness. The other complaint was formation of a cystic mass in the right external auditory canal. The patient underwent surgery via a mini middle cranial fossa craniotomy associated with a transmastoid approach.

CONCLUSION

Although presenting symptoms can be subtle, early suspicion and confirmatory imaging aid in establishing the diagnosis. The combination of computed tomography and magnetic resonance imaging will help in proper preoperative diagnosis. The operation includes transmastoid, middle cranial fossa repair, or combination of both. The multilayer closure of bony defect is very important to avoid cerebrospinal fluid leak. Clinical manifestations, diagnosis, and surgical approaches for posttraumatic meningoencephaloceles arising in the head and neck region are briefly discussed.

Endoscopic management of cerebrospinal fluid rhinorrhea

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

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.

The usefulness of MDCT-myelography for patients with spontaneous intracranial hypotension

Purpose

The detection and localization of cerebrospinal fluid (CSF) leakage in patients with spontaneous intracranial hypotension (SIH) is important. The aim of this study was to evaluate the usefulness of multidetector CT (MDCT)-myelography in patients with SIH.

Methods

A radiologist retrospectively searched the electronic database to find the patients who had undergone MDCT-myelography for SIH between October 2010 and September 2014. In the MDCT-myelographic treatment, the patient’s whole spine was scanned by 64 or 256 channel MDCT scanners after being injected with 20 ml of contrast agent via L3/4 interlaminar space under fluoroscopic guidance. Three radiologists in consensus determined the presence, pattern (“pseudodiverticular sign” or “gray-rim sign”) and level of contrast leakage outside the dural sac.

Results

Eighteen patients (M:F = 9:9; mean age, 36.2; age range 17–56) were finally included in this study. CSF leakage was detected in 17 of 18 patients. CSF leakage pattern was described as a “pseudodiverticular sign” in five and “gray-rim sign” in ten patients. Leakage level could be determined in ten patients based on MDCT-myelography.

Conclusions

MDCT-myelography was useful to detect CSF leakage and to guess the leakage level in patients with SIH.

In Vivo Detection of Amyloid Plaques by Gadolinium-Stained MRI Can Be Used to Demonstrate the Efficacy of an Anti-amyloid Immunotherapy

Extracellular deposition of β amyloid plaques is an early event associated to Alzheimer’s disease. Here, we have used in vivo gadolinium-stained high resolution (29^∗29^∗117 μm³) magnetic resonance imaging (MRI) to follow-up in a longitudinal way individual amyloid plaques in APP/PS1 mice and evaluate the efficacy of a new immunotherapy (SAR255952) directed against protofibrillar and fibrillary forms of Aβ. APP/PS1 mice were treated for 5 months between the age of 3.5 and 8.5 months. SAR255952 reduced amyloid load in 8.5-months-old animals, but not in 5.5-months animals compared to mice treated with a control antibody (DM4). Histological evaluation confirmed the reduction of amyloid load and revealed a lower density of amyloid plaques in 8.5-months SAR255952-treated animals. The longitudinal follow-up of individual amyloid plaques by MRI revealed that plaques that were visible at 5.5 months were still visible at 8.5 months in both SAR255952 and DM4-treated mice. This suggests that the amyloid load reduction induced by SAR255952 is related to a slowing down in the formation of new plaques rather than to the clearance of already formed plaques.

Children With Intracranial Arachnoid Cysts: Classification and Treatment

We performed a dynamic study of arachnoid cysts (ACs) using magnetic resonance cisternography (MRC) and proposed a classification of ACs.Twenty-three suitable patients in our hospital entered into this study according to our inclusion criteria. MRC images were collected in all the subjects at 1 and 24 hours after the administration of intrathecal gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA). We allocate the enrolled patients into 2 groups, MRC group and surgery group. The MRC results were considered before treatment in 1 group (MRC group, 13 patients), whereas another group was surgically treated without considering the MRC results (surgery group, 10 patients). We calculated the enhanced area of cyst using modified MacDonald Criteria from the images and measured the surrounding subarachnoid area as the reference.We found that it was practically useful to quantify 3 types of ACs, complete communicating, incomplete communicating, and noncommunicating, according to MRC results in this study. All the subjects in both groups are closely observed before the treatment and the follow-up using the MRI examination. In the surgery group, 5 patients were found that the area of cysts shrank in the follow-up stage. However, there was no significant difference in the percentage shrinkage area between the 2 groups.We concluded that MRC with Gd-DTPA as a contrast agent is of significant clinical value for the diagnosis and treatment of children with intracranial ACs. This classification based on dynamic MRC is useful for making surgical recommendations.

The endoscopic endonasal approach to repair of iatrogenic and noniatrogenic cerebrospinal fluid leaks and encephaloceles of the anterior cranial fossa

OBJECTIVE

The current approach for the diagnosis and repair of spontaneous and traumatic anterior skull-base defects is oulined, highlighting the controversies that exist in the field and describing the strategies required to access different segments of the anterior cranial fossa.

METHODS

We reviewed the literature concerning endoscopic management of anterior skull-base defects. These publications have been combined with our own experience repairing cerebrospinal fluid (CSF) leaks and encephaloceles that developed spontaneously, traumatically, or intentionally as a result of endoscopic skull-base surgery.

RESULTS

We present a systematic methodology for the repair of these defects. We have divided our surgical approach into four separate corridors. These are the transnasal, transsphenoidal, transethmoidal, and transmaxillary corridors. Dissection strategies vary for each corridor, but with a combination of approaches, all areas of the anterior skull base can be accessed. Skull-base defects are successfully repaired with a multilayered closure that often involves use of a vascularized pedicled mucosal flap. Adoption of this technique has decreased our rate of postoperative CSF leak from 5.9%-3.1%.

CONCLUSIONS

Endoscopic endonasal repair of CSF leaks and encephaloceles has evolved significantly during the past decade. The versatility of different endoscopic approaches through the four endonasal corridors allows for the endoscopic repair of almost all skull-base defects. The use of vascularized pedicled mucosal flaps has evolved to cover these defects as part of multilayered closure strategies.

A practical approach to the imaging interpretation of sphenoid sinus pathology

The goal of this article is to provide a practical approach to the imaging interpretation of sphenoid sinus pathology. Basic anatomy and physiology is reviewed first. This is followed by a discussion of the imaging modalities used to evaluate the sphenoid sinuses and how to differentiate a benign from an aggressive lesion. Finally, disease entities are discussed, with attention to clinical presentation, expected imaging appearance, and treatment. Although the focus is on sphenoid sinus pathology, the concepts presented can be applied to interpretation of disease in any paranasal sinus.

A novel technology: percutaneous injection of fibrin glue as a treatment for frontal sinus cerebrospinal fluid rhinorrhea

In this study, we examined the effectiveness of percutaneous injected fibrin glue as a treatment for frontal sinus cerebrospinal fluid (CSF) rhinorrhea in a series of 4 cases. All 4 patients had fracture in the posterior wall of the frontal sinus. The anterior wall of the frontal sinus was punctured following high-resolution computed tomography imaging. In 3 out of 4 patients with defective skull due to prior frontal craniotomy, direct percutaneous puncture of the frontal sinus was used. Fibrin glue was injected to close the fistula and to seal the rhinorrhea. Surgery procedures lasted for 15-35 minutes (average 27.6 min). Rhinorrhea was stopped in all patients after the surgery, with no recurrence at a 10-month follow-up visit. In 1 case, the glue was expelled by coughing at 2 days after the surgery but was completely stopped with no recurrence after a second attempt. One patient with no recurrence at a 10-month follow-up died of tumor relapse at 12 months. In summary, fibrin glue could be used as a novel treatment for frontal sinus CSF rhinorrhea.

A rare case of Chiari type-1 malformation accompanied by symptomatic cerebrospinal fluid hypovolemia: comparison of congenital Chiari type-1 malformation and acquired Chiari malformation secondary to cerebrospinal fluid hypovolemia: case report

A 23-year-old woman was injured in a rear-end collision. She had general malaise and posterior neck pain, which were more severe when she was in an upright position. Magnetic resonance imaging (MRI) revealed the presence of cerebellar tonsil descensus and syringomyelia in the spinal cord. Radioisotope (RI) cisternography showed signs of an early accumulation of RI in the bladder, and a delayed accumulation of RI in the cerebral fornix. We considered the possibilities of cerebrospinal fluid (CSF) hypovolemia and congenital Chiari type-1 malformation as being responsible for her headache. To obtain a definitive diagnosis, we performed gadolinium (Gd)-enhanced MR cisternography and found evidence of CSF leakage. We performed an epidural blood patch (EBP), and her symptoms resolved. In 2 years since the episode, her symptoms have not recurred, and additional treatment has not been required. In addition, MRI performed 2 years after the EBP did not reveal any changes. There seems no previous report which described successful differentiation of pre-existing congenital Chiari type-1 malformation from the acquired one caused by symptomatic CSF hypovolemia. Because treatment protocols differ between these two conditions, the establishment of a correct diagnosis is important.

Lumbar puncture-related cerebrospinal fluid leakage on magnetic resonance myelography: is it a clinically significant finding?

Background

Post-dural puncture headache (PDPH) due to excessive cerebrospinal fluid (CSF) leakage is a well-known complication of lumbar puncture. Although various factors, especially the type of spinal needle, have been demonstrated to be associated with PDPH, the clinical implications of CSF leakage detected on magnetic resonance myelography (MRM) images remain unclear. The objective of this case–control study was to evaluate the association between radiologically visualized CSF leakage and PDPH.

Methods

Clinical data including patients’ age and gender, types of spinal needle, duration of bed rest, interval between lumbar puncture procedures and MRM studies, and incidence of PDPH were compared between patients who were radiologically-positive and -negative for CSF leakage.

Results

Of the 22 patients with definite CSF leakage on MRM images, most were asymptomatic (86%, 19/22). The remaining three patients, who were suffering from PDPH, only complained of headaches and were treated conservatively. In a review of patients’ clinical data, there were no significant differences in any parameter including the incidence of PDPH between the 22 patients who were radiologically-positive for CSF leakage and the 31 radiologically-negative patients.

Conclusion

The significance of radiologically visualized CSF leakage should not be overestimated, as most such incidents are not associated with PDPH and do not require any treatment.

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.

Lesions of the skull base: imaging for diagnosis and treatment

This article provides a summary of how to approach the imaging analysis of lesions of the anterior, central, and posterior skull base. The primary focus is tumors and tumor-mimickers, and representative examples are shown to differentiate the features of lesions that can occur in the same location.

Intracystic gadolinium-enhanced MRI in the evaluation of residual giant-cystic craniopharyngiomas in children: report of four cases

Residual giant-cystic craniopharyngiomas are amenable to intracavitary bleomycin treatment. Radiologic identification of potential cyst leaks is of paramount for treatment decisions. This report describes our experience in the use of intracystic Gadolinium (Gd)-enhanced MR imaging to determine potential communications between the tumoral cysts and other intra-axial spaces in 4 pediatric patients with residual giant-cystic craniopharyngiomas in whom intracavitary bleomycin treatment was planned after the injection of .1-.2 mL of gadopentetate dimeglumine (Gd-DTPA). In three cases no leaks were found. In one case, whose previous water-soluble iodinated contrast-enhanced CT cystography was negative for leaks, intracystic Gd-enhanced MR showed intraventricular Gd enhancement. We conclude that MR imaging after intracystic administration of Gd-based contrast paramagnetic agents is useful in the detection of potential leaks in cases of giant residual craniopharyngiomas.

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.

The role of MR myelography with intrathecal gadolinium in localization of spinal CSF leaks in patients with spontaneous intracranial hypotension

BACKGROUND AND PURPOSE

Localization of spinal CSF leaks in CSF hypovolemia is critical in directing focal therapy. In this retrospective review, our aim was to determine whether GdM was helpful in confirming and localizing spinal CSF leaks in patients in whom no leak was identified on a prior CTM.

MATERIALS AND METHODS

Forty-one symptomatic patients with clinical suspicion of SIH were referred for GdM after undergoing at least 1 CTM between February 2002 and August 2010. A retrospective review of the imaging and electronic medical records was performed on each patient.

RESULTS

In 17 of the 41 patients (41%), GdM was performed for follow-up of a previously documented leak at CTM. In the remaining 24 patients (59%), in whom GdM was performed for a suspected CSF leak, which was not identified on CTM, GdM localized the CSF leak in 5 of 24 patients (21%). In 1 of these 5 patients, GdM detected the site of leak despite negative findings on brain MR imaging, spine MR imaging, and CTM of the entire spine. Sixteen of 17 patients with previously identified leaks underwent interval treatment, and leaks were again identified in 12 of 17 (71%).

CONCLUSIONS

GdM is a useful technique in the highly select group of patients who have debilitating symptoms of SIH, a high clinical index of suspicion of spinal CSF leak, and no demonstrated leak on conventional CTM. Intrathecal injection of gadolinium contrast remains an off-label use and should be reserved for those patients who fail conventional CTM.