Bowel visualization during indium-111-labelled diethylene triamine penta-acetic acid cisternography due to massive cerebrospinal fluid leak. Case report and review of the literature

We report a case of massive cerebrospinal fluid (CSF) leakage where the tracer injected intra-thecally for radionuclide cisternography was later visualized in the bowel as well as the nasopharynx. We discuss the potential implications of this finding in patients with CSF leaks. A brief review of the diagnosis of CSF leaks is included.     

Co-existing fast CSF leaks and CSF-venous fistulas on dynamic CT myelography

Spontaneous intracranial hypotension can be caused by spinal dural tears or CSF-venous fistulas. It is rare for patients to have more than one type of leak at any given time. Here, we illustrate 3 examples of dural tears that co-existed with CSF-venous fistulas, with both being seen on dynamic CT myelography. To our knowledge, coexistent CSF-venous fistulas and dural tears have not been previously illustrated on dynamic CT myelography, even though this is one of the most commonly used modalities to work-up patients with CSF leaks. We discuss the clinical importance of the rare co-occurrence of these leaks with regard to diagnosis and treatment, as well as implications for understanding and classifying CSF leaks.     

Dual energy CT for the identification of CSF-Venous Fistulas and CSF leaks in spontaneous intracranial hypotension: Report of four cases

Spontaneous intracranial hypotension (SIH) is a debilitating condition caused by spinal CSF leaks or CSF-venous fistulas (CVFs). Localizing the causative CSF leak or CVF is critical for definitive treatment but can be difficult using conventional myelographic techniques because these lesions are often low contrast compared to background, diminutive, and in some cases may be mistaken for calcified structures. Dual energy CT (DECT) can increase the conspicuity of iodinated contrast compared to background and can provide the ability to distinguish materials based on differing anatomic properties, making it well suited to address the shortcomings of conventional myelography in SIH. The purpose of this report is to illustrate the potential benefits of using DECT as an adjunct to traditional myelographic techniques in order to increase the conspicuity of these often-subtle CVFs and CSF leaks. This retrospective case series included 4 adult patients with SIH who demonstrated findings equivocal for either CVF or CSF leak using our institution''s standard initial CT myelogram and in whom subsequent evaluation with DECT ultimately helped to identify the CVF or CSF leak. DECT demonstrated utility by increasing the conspicuity of two subtle CVFs compared to background and also helped to differentiate between calcified osteophytes and extradural contrast in 2 CSF leaks, confirming their presence and identifying the causative pathology. Our observations demonstrate the benefit of DECT as a problem-solving tool in the accurate diagnosis and localization of CVFs and CSF leaks.     

Dynamic CT myelography: a technique for localizing high-flow spinal cerebrospinal fluid leaks

In some patients with spontaneous spinal CSF leaks, leaks are numerous or tears are so large that extrathecal myelographic contrast material is seen at multiple levels during CT, making identification of their source impossible. This study introduces a dynamic CT myelographic technique that provides high temporal and spatial resolution. In this technical note, we describe the utility of this technique in four patients with challenging high-flow spinal CSF leaks.     

双能量CT脊髓造影诊断自发性颅内低压脊髓脑脊液漏的初步研究

目的 探讨双能量CT脊髓造影(CTM)检查在自发性颅内低压(SIH)脊髓脑脊液漏中的诊断价值.方法 对6例诊断为SIH的患者行双能量脊髓CT造影检查,X线管电压分别设定为100和140 kVp(加锡过滤片),后处理获得虚拟平扫(VNC)、碘图等图像,并与合成的120 kVp CTM进行对比,比较2种方法在显示对比剂沿神经根外漏、C1～2椎体后方对比剂积聚、硬膜静脉丛扩张及椎管内硬膜下对比剂积聚等方面的情况.运用Kappa一致性检验比较2种方法诊断脑脊液漏点的差异.结果 6例患者合成的120 kVp CTM共显示43个漏点,其中的41个漏点在VNC和碘图上显示,2种方法在脊膜脑脊液漏点检出上有非常好的一致性(Kappa值=0.997,P＜0.01),并且2种方法均显示C1～2椎体后方对比剂积聚(2例)、硬膜外对比剂积聚(3例)及静脉丛扩张(1例),双能量CTM碘图和VNC图像视觉显示效果更佳.结论 双能量CTM可用于SIH脊髓脑脊液漏的诊断.

Abstract：

Objective To assess the value of dual-energy computed tomography myelography (CTM) on detecting leaks of cerebrospinal fluid (CSF) in patients with spontaneous intracranial hypotension (SIH). Methods Six patients with SIH underwent spinal CTM on a 2nd generation dual-source CT with tube voltage set at 100 and 140 kVp(with tin filter). The virtual non-contrast (VNC) and iodine map images were calculated from dual-energy images. The average weighted (AW) CTM images were mixed from two kVp images with mix factor of 0. 5. Two radiologists evaluated CSF leak using two sets of images respectively: VNC + iodine map images and AW-CTM images. The results from two reading methods were compared. The level of CSF leaks along the nerve roots, C1-2 retrospinal CSF collections, epidural CSF collections and spinal epidural venous plexus were marked. The consensus about leak sites and CSF collections was made by two radiologists in the third session Kappa statistics were used to measure the agreement between the two methods. Results Forty-one leaks were detected using VNC + iodine map images. Forty-three leaks were detected on AW images. The agreement between two methods was excellent (Kappa =0. 997 ,P ＜0. 01). There were no differences in the detection of C1-2 retrospinal CSF collections (n = 2), epidural CSF collections(n = 3) or spinal epidural venous plexus (n = 1). VNC and iodine map images demonstrated superior visual effects than AW images. Conclusion Dual-energy CTM can be used to diagnose spontaneous spinal cerebrospinal fluid leaks in SIH patient.     

Spontaneous intracranial hypotension from calcified thoracic disc protrusions causing CSF leak successfully treated with targeted epidural blood patch

Spontaneous spinal cerebrospinal fluid (CSF) leaks are increasingly recognized in patients presenting with orthostatic headache and ultimately diagnosed with intracranial hypotension. While the precise cause of these spontaneous leaks is unknown, it is thought to result from underlying weakness in the spinal meninges and may be associated with meningeal diverticula or Tarlov cysts. Rarely, calcified intervertebral discs or bony osteophytes can result in CSF leakage, which has been described in the surgery literature but not well recognized in the radiology literature. The authors present three cases of patients presenting with CSF leaks from calcified thoracic disc protrusions that were successfully treated with epidural blood patches.     

CSF leaks: correlation of high-resolution CT and multiplanar reformations with intraoperative endoscopic findings

BACKGROUND AND PURPOSE: Skull base defects can result in CSF leaks, with meningitis as a potential complication. Surgeons are now routinely repairing these leaks via a nasal endoscopic approach. Accurate preoperative imaging is essential for surgical planning. A variety of imaging regimens have been employed, including axial and direct coronal CT, CT cisternography with iodinated contrast, radionuclide cisternography, and MR imaging. Now that multidetector helical CT is available, the purpose of this study was to determine how well coronal and sagittal multiplanar reformatted (MPR) images generated from a high-resolution axial dataset correlate with intraoperative findings in a group of patients with clinically proved CSF leaks.MATERIALS AND METHODS: We retrospectively reviewed imaging findings and surgical records of 19 patients who presented to our tertiary care institution during a 2.5-year period with clinically proved CSF leak. Patients underwent preoperative imaging with high-resolution helical CT (section collimation, 10 patients with 0.625-mm and 9 patients with 1.25-mm images), with MPR images processed by a neuroradiologist at a workstation. Two neuroradiologists, blinded to the intraoperative findings, determined the location and size of the skull base defects. All patients underwent endoscopic evaluation by an experienced sinonasal otolaryngologist, who confirmed the site of the CSF leak by direct inspection and measured the corresponding osseous defect. CT was considered accurate if it correctly localized the CSF leak and was within 2 mm of the endoscopic measurement.RESULTS: At endoscopy, 22 leaks of CSF were identified in 18 of 19 patients. CT correctly predicted the site of the leak in 20 (91%) of 22 cases and was accurate (within 2 mm of the endoscopic measurement) in 15 (75%) of 20 cases preoperatively localized. The CT measurement of the skull base defect differed from the endoscopic size in 5 (25%) of 20 cases, ranging from 7.4 mm below to 13 mm above the intraoperative measurement. When analysis was limited to the subgroup of 10 patients who had 0.625-mm axial images, the accuracy was improved, and of the 11 CSF leaks described at CT, all were verified at endoscopy. In addition, the submillimeter CT accurately measured the size of the osseous defect in 9 (82%) of 11 cases. In the remaining 2 (18%) of 11 cases, CT minimally overestimated the size of the osseous defect by only 3 mm.CONCLUSION: Axial images, and coronal, sagittal, and oblique MPR images generated from high-resolution axial CT performed well preoperatively, localizing the skull base defect responsible for the CSF leak. However, active manipulation of the axial dataset at a workstation is crucial in identifying and correctly describing these lesions. When submillimeter collimation is available, measurement of the osseous defects are accurate most of the time.

Skull base defects that result in dural tears and CSF leaks can be associated with significant long-term disability, primarily related to central nervous system infection. Bacterial meningitis is the major cause of morbidity and mortality, with encephalitis and parenchymal abscess occurring much less frequently¹. Left untreated, some may resolve spontaneously, but the risk for meningitis is 10% annually and up to 40% in the long term.² CSF leaks occur in approximately 2% of closed head injuries, the most common cause of CSF leak.³ Other causes include a tumor or developmental malformations of the skull base, and surgical trauma. CSF leaks may also arise spontaneously, especially in the setting of idiopathic intracranial hypertension. More than 90% of CSF leaks are successfully treated by minimally invasive intranasal endoscopic repair.^2,3 Even when CSF leaks cease spontaneously, early endoscopic repair is often considered because of a significant risk, estimated at 30% to 40%, for ascending meningitis.³In patients with profuse posttraumatic or postsurgical CSF leaks, the diagnosis is obvious. However, in patients with intermittent CSF leaks that result in minimal discharge, the diagnosis may remain elusive. In this circumstance, beta2-transferrin (β₂-TF) assay provides a highly sensitive and specific (97% and 99%, respectively) method to confirm CSF leak.⁴ β₂-TF protein is found almost exclusively in CSF, and as little as 0.5 mL of CSF is needed for the assay.³ Once the clinical suspicion of CSF leak is confirmed with β₂-TF, the skull base defect responsible for the leak must be identified.A variety of diagnostic modalities have been proposed for the preoperative localization of CSF leaks. In the traditional sense, CT and radionuclide cisternography have been the mainstays in the diagnostic evaluation, but their accuracy diminishes when CSF leaks are intermittent, a frequent occurrence. More recently, high-resolution CT without intrathecal contrast and with the use of axial and direct coronal planes has been shown to reliably demonstrate skull base defects that result in CSF leaks.^5,6 With this technique, the skull base defect can be localized even when there is no active leak. Given that coronal images are essential in identifying skull base defects, the purpose of our study was to determine how well high-resolution coronal, sagittal, and oblique multiplanar reformatted (MPR) images generated from an axial dataset correctly predict the site of a CSF leak. It is perhaps more important to note that our series is the first, to our knowledge, to evaluate how accurately CT measurements compare with intraoperative sizes of the responsible skull base defects.     

“The Up and Down Approach” to Localize and Exclude Sites of Intraspinal CSF Leaks

Myelography is a commonly performed procedure to locate cerebrospinal fluid (CSF) leaks in patients with spontaneous intracranial hypotension. Often, the site of leak within the spinal canal cannot be located creating a diagnostic dilemma for clinicians. This technical report describes a novel method to locate and exclude intraspinal CSF leaks in patients with multiple potential sites of CSF leak using a lumbar and cervical approach to inject intrathecal contrast and subsequently performing CT myelography.     

Fellows' Journal Club: When Should I Do Dynamic CT Myelography? Predicting Fast Spinal CSF Leaks in Patients with Spontaneous Intracranial Hypotension

BACKGROUND AND PURPOSE:Some patients with SIH have fast CSF leaks requiring dynamic CTM for localization; however, patients generally undergo conventional CTM before a dynamic study. Our aim was to determine whether findings on head MR imaging, spine MR imaging, or opening pressure measurements can predict fast spinal CSF leaks.MATERIALS AND METHODS:A retrospective review was performed on 151 consecutive patients referred for CTM to evaluate for spinal CSF leak. Head MR imaging was evaluated for diffuse dural enhancement and “brain sag,” and spine MR imaging for presence of an extradural fluid collection. The opening pressure was recorded. The CTM was scored as no leak, slow leak localized on conventional CTM, or fast leak that required dynamic CTM.RESULTS:Fast CSF leaks were identified in 32 (21%), slow leaks in 36 (24%), and no leak in 83 (55%) of 151 patients on initial CTM. There was significant association between spinal extra-arachnoid fluid on MR imaging and the presence of a fast leak (sensitivity 85%, specificity 79%, P < .0001). There was not significant association between fast leak and findings on head MR imaging (P = .27) or opening pressure (P = .30).CONCLUSIONS:If all patients with spinal extra-arachnoid CSF on MR imaging had been sent directly to dynamic CTM, repeat myelography would have been avoided in most patients with fast leaks (23 of 27; 85%). However, a minority of patients with slow or no leaks would have been converted from conventional to dynamic CTM (16 of 77; 21%). Spinal MR imaging is helpful in premyelographic evaluation of SIH.

While some patients with SIH recover without intervention or display a self-limited course, many do require an invasive therapeutic intervention.¹ In those patients who do not respond to multiple large-volume epidural blood patches, targeted epidural blood patches, targeted fibrin glue injections, or surgical repair may be necessary. In these patients, localization of the actual site or sites of CSF leak is critical for guiding therapy. In many patients, the site of leak can be localized using conventional CTM. When there are multiple leaks or large dural tears, the time delay during transfer between the myelographic portion of the examination performed with fluoroscopy and the CT portion of the examination allows the extra-arachnoid contrast to diffuse over multiple spinal levels, thus limiting the ability to localize the leaks to within 2 spinal segments. We define these as high-flow or fast leaks, which require dynamic CTM to localize.²When performing dynamic CTM, a spinal needle is either placed under fluoroscopic guidance, and then the patient is transferred from the fluoroscopy suite to a CT scanner, or the spinal needle is placed under CT guidance. The myelographic contrast is then injected with the patient in the CT scanner. This allows for immediate CT acquisition following contrast injection and localization of fast CSF leaks.^2,3 Because multiple CT acquisitions are performed, dynamic CTM is associated with a higher radiation dose and is performed without the benefit of a tilting table. Therefore, in the past, we have advocated conventional CTM before considering a dynamic study.² The aims of this study were to determine how frequently dynamic CTM must be performed following the initial conventional CT myelogram in order to localize fast CSF leaks, and to determine whether findings on head MR imaging, spine MR imaging, or opening pressure measurements can predict fast spinal CSF leaks in a large case series.     

Postoperative cerebrospinal fluid leaks of the lumbosacral spine: management with percutaneous fibrin glue.

PURPOSETo assess CT-guided injection of fibrin glue for the management of lumbosacral cerebrospinal fluid (CSF) leaks.METHODSSix consecutive patients with postoperative CSF leaks were treated after CSF aspiration under CT guidance. A solution of cryoprecipitate was simultaneously injected with a 10% calcium chloride solution containing 2000 units of thrombin per milliliter. In one patient, 0.5 mL of iopamidol was added to the calcium chloride/thrombin mixture before injection. Placement of the fibrin glue aggregate was confirmed by CT imaging. To determine outcomes we reviewed the patients'' records, postprocedure imaging studies, and physical findings, and we interviewed the patients directly.RESULTSIn three patients with postoperative CSF leaks, symptoms resolved after treatment. Despite imaging evidence of successful plug deployment, two other patients still had severe symptoms, and they underwent surgery after 2 and 18 hours, respectively. One patient had a continued CSF leak and a headache after 12 hours; follow-up surgery repaired an unsuspected dural tear just distal to the site of original surgery underneath the lamina and not covered by the fibrin glue. After one of the successful procedures, the patient had a fever and a headache, probably because of aseptic meningitis, which resolved after 2 days.CONCLUSIONPercutaneous CT-guided placement of fibrin glue may provide nonsurgical treatment for postoperative CSF leaks, potentially avoiding a major and technically difficult surgical procedure.     

MR imaging evaluation of endoscopic cranial base reconstruction with pedicled nasoseptal flap following endoscopic endonasal skull base surgery

Introduction

Postoperative CSF leak is the most common complication of endoscopic endonasal approach (EEA) to skull base lesions. Endoscopic multilayer closure of skull base defect using pedicled nasoseptal flaps (NSF) based off the sphenopalatine artery reduces CSF leaks. EEA robustly expands in surgical arena, yet postoperative imaging evaluation remains poorly studied. This work illustrates normal MR imaging appearance of skull base reconstruction utilizing NSFs during immediate postoperative period.

Methods

We retrospectively identified patients who had skull base reconstructions utilizing NSFs following EEAs and immediate postoperative-enhanced brain MRI. NSFs and free grafts were evaluated for signal intensity, thickness, configuration, enhancement, vascular pedicle of NSF, relationship in multilayer reconstruction, and defect coverage. Imaging findings were correlated with surgical technique and CSF leaks.

Results

Twenty-eight patients had 26 multilayer reconstructions and 34 NSFs. Twenty-nine NSFs showed enhancing C-shaped arc at the skull base. Of those, 26 flaps (90%) were confidently identified by visualization of their vascular pedicles, 3 were not distinguishable from adjacent mucosa and pedicles were not identified. Five NSFs showed no enhancement (1 CSF leak). Twenty-seven enhancing NSFs approximated defects with close abutment to free grafts. One flap was displaced; one incompletely covered the defect (2 CSF leaks). Fisher exact test demonstrated an association between incomplete defect coverage and displacement of NSFs with CSF leak (P = 0.05).

Conclusion

Endoscopic skull base reconstruction utilizing NSF has characteristic MR imaging appearance. Non-enhancing mucosal gap or displacement of NSF may indicate incomplete defect coverage, identifying patients at risk for CSF leak.     

Trans-sphenoidal treatment of postsurgical cerebrospinal fluid fistula: CT-guided closure

Abstract Cerebrospinal fluid (CSF) leakage after trans-sphenoidal surgery is a troublesome complication with a risk of meningitis and pneumocephalus. We suggest CT-guided intrasphenoidal injection of fibrin sealant through a 12-gauge needle as a simple alternative to surgical management of CSF fistulae. We treated eight patients, operated via the trans-sphenoidal route (five pituitary adenomas, three craniopharyngiomas), for a postoperative CSF leak by CT-guided intrasphenoidal injection of fibrin sealant alone in three cases and fibrin sealant and autologous blood in 5. CT was obtained 10 days after the procedure in all cases. In four patients, the CSF leak was closed successfully at the first attempt. The procedure was repeated on the four remaining patients because only a reduction in leakage was obtained at the first attempt. This procedure preserves olfaction and avoids the risk of frontal lobe damage. It could therefore represent the treatment of choice in many cases of anterior cranial fossa postsurgical CSF leaks. Received: 27 March 1997 Accepted: 16 December 1997     

MR cisternography after intrathecal Gd-DTPA application

The purpose of this study was to establish and to evaluate MR cisternography after intrathecal Gd-DTPA administration to detect rhinobasal cerebrospinal fluid (CSF) fistulae in patients with suspected CSF rhinorrhoea. Ten patients with suspected CSF rhinorrhoea were examined. The MR cisternography included the following investigation steps: acquisition of nonenhanced fat-suppressed T1-weighted spin-echo (SE) scans of the skull base and the paranasal sinuses, lumbar puncture with administration of 1 ml Gd-DTPA solute with 4 ml NaCl and performance of MR cisternography with the same fat-suppressed T1-weighted sequences as used initially. In 10 patients with suspected CSF rhinorrhoea Gd-DTPA enhanced MR cisternography detected 5 CSF fistulae. In 3 of 5 CSF leaks were located in the cribriform plate and in 2 of 5 sphenoidal. Whereas 4 of these depicted leaks were confirmed surgically, in 1 case the CSF fistula closed spontaneously. In another case, CSF leakage after severe head injury was clinically highly suspected but ceased prior to MR cisternography with inability to detect the temporary fistula. In the remaining 4 patients with serous rhinorrhoea MR cisternography did not provide any evidences for CSF fistulae. Intrathecal Gd-DTPA injection was tolerated excellently. Clinical and EEG examinations showed no gross behavioural or neurological disturbances and no seizure activity, respectively. The MR cisternography after intrathecal administration of Gd-DTPA represents a safe, promising and minimally invasive method for detection of CSF fistulae. This MR investigation provides excellent depiction of CSF spaces and pinpoints CSF fistulae. Electronic Publication     

自发性低颅压综合征脑脊液间隙显像的影像学特征分析

目的 探讨自发性低颅压综合征（SIH）患者放射性核素脑脊液间隙显像（RNC）的影像学特点及其临床意义。 方法 回顾性分析2012年5月至2017年1月福建省立医院收治的19例SIH患者,均经腰椎穿刺脊髓蛛网膜下腔注射99Tcm-DTPA,行多时相脑脊液间隙显像,对99Tcm-DTPA异常分布处加做SPECT/CT断层融合显像及MRI扫描。综合分析RNC的影像学特点。计数资料的组间比较采用 χ 2 检验。 结果 RNC可通过显示脊髓或鼻部脑脊液漏点等直接征象诊断SIH;也可通过观察脑脊液循环过程异常,如:显像剂上升缓慢,难以抵达脑池、大脑凸面、上矢状窦等及膀胱、肾脏早期显像等间接征象诊断SIH。RNC检出脑脊液漏17例。直接脑脊液漏患者12例,其中颈、胸段9例,脑脊液鼻漏2例,大流量脑脊液漏（腰段）患者1例。RNC正常者2例。MRI[阳性率为58.8%（10/17）]与RNC[阳性率为88.2%（15/17）]对SIH低颅压诊断的差异无统计学意义（χ2=0.101,P>0.05）;12例RNC检出漏口的相应部位MRI仅检出1例。 结论 RNC可通过直接或间接征象协助SIH的病因诊断,在脑脊液漏口检出上明显优于MRI,并可反映脑脊液漏的流量,便于个体化治疗,在SIH的诊疗中有重要的应用价值。     

MRI cisternography with gadolinium-containing contrast medium: its role,advantages and limitations in the investigation of rhinorrhoea

Our purpose was to evaluate the utility of intrathecal gadopentetate dimeglumine -enhanced magnetic resonance cisternography (GdMRC). We injected 0.5 ml contrast medium into the subarachnoid space via lumbar puncture in 20 patients with suspected cerebrospinal fluid (CSF) rhinorrhoea. MRC showed CSF leakage in 14 patients with rhinorrhoea at the time of the examination, into the ethmoid air cells in nine, the sphenoid sinus in three and the frontal sinus in two cases. In 12 of these the site leakage was confirmed during surgical repair of the fistula. No leakage was observed in four patients with intermittent rhinorrhoea, not present at the time of the examination. GdMRC showed leakage in two patients with negative CT cisternography. GdMRC may prove better than CT cisternography, especially with slow CSF flow. We also showed low-dose GdMRC to be a feasible and relative safe way of confirming the presence of and localising active CSF leaks prior to surgical repair.     

Reversal in the Diameter of the Superior Ophthalmic Vein after an Epidural Blood Patch in a Case of Spontaneous Intracranial Hypotension

Spontaneous intracranial hypotension (SIH) is caused by single or multiple cerebrospinal fluid (CSF) leaks in the spine with the prototypical symptom of postural headache. One of the characteristic MRI features in SIH is intracranial venous engorgement. This report presents a case of SIH with engorgement of the bilateral superior ophthalmic veins (SOVs) which resume their normal diameters by the third day of successful epidural blood patches (EBPs). We define this phenomenon as the "reversal of the SOV" sign.     

Gadolinium-enhanced MR cisternography to evaluate dural leaks in intracranial hypotension syndrome

Background and PURPOSE: We evaluated the use of MR cisternography after intrathecal administration of gadopentetate dimeglumine to detect the presence and localization of CSF leaks in 19 patients diagnosed with spontaneous intracranial hypotension syndrome according to the criteria of International Headache Society.MATERIALS AND METHODS: Lumbar puncture with an injection of 0.5 mL of gadopentetate dimeglumine into the subarachnoid space in the lumbar area was performed. MR images of the cervical, thoracic, and lumbar regions in axial, coronal, and sagittal planes with fat-saturated T1-weighted images were acquired.RESULTS: We observed objective CSF leakage in 17 (89%) of 19 patients. In 14 of these 17 patients, the site of dural tear was demonstrated accurately. In 3 of these 17 patients, the contrast leakage was diffuse, and site of the leak could not be located accurately. No leakage was observed in 2 patients. No complications were detected in any of the patients during the first 24 hours after the procedure or during the 6- to 12-month follow-up.CONCLUSION: The current results demonstrate the relative safety, accuracy, and feasibility of intrathecal gadolinium-enhanced MR cisternography to evaluate dural leaks.

The spontaneous intracranial hypotension (SIH) syndrome was originally described by the German neurologist Schaltenbrand^1,2 in 1938 as hypoliquorrhea. The Headache Classification Subcommittee of the International Headache Society has proposed diagnostic criteria for SIH.³ Evidence of CSF leakage was accepted as one of the main criteria for SIH diagnosis according to International Classification of Headache Disorders.³ Although many patients with SIH recover without intervention, many do not.^4,5 Some of these patients do not respond to multiple epidural blood patches and may require more targeted epidural injections, infusions, or surgical repair.^4–6 In these patients, confirmation of CSF leak, localization of the actual site or sites of CSF leak, and characteristics of the dural leaks become important. Despite advances in imaging and the availability of several different and potentially useful diagnostic modalities, accurate demonstration of the site of the CSF leakage remains a challenge for radiologists and clinicians. The purpose of our study was to evaluate and report our initial experience in analyzing CSF leaks in SIH using MR imaging combined with intrathecal administration of a gadolinium-based contrast agent, that is, gadolinium-enhanced MR cisternography.     

Tarlov cysts: an overlooked clinical problem

Symptomatic Tarlov cysts typically cause chronic pelvic and lower extremity pain and sacral nerve root radiculopathy. Historically, open surgical treatment involved significant patient morbidity, particularly postoperative cerebrospinal fluid (CSF) leaks and infection. These CSF leaks often required multiple surgical procedures to seal. Over the past 20 years, there have been two or three isolated case reports of computed tomography (CT)-guided needle aspirations that offered limited evidence of treatment efficacy and safety. Some have reported high rates of postprocedure aseptic meningitis that were not well explained. These poor results dissuaded physicians from caring for these patients. As a group these patients are usually treated dismissively and told their cysts are asymptomatic and their pain must be coming from somewhere else. Many of them have had an unnecessary discectomy or a spinal fusion, and when these procedures did not relieve their pain they were told they are a "failed back patient." We have treated more than a hundred patients with symptomatic Tarlov cysts by CT fluoroscopic-guided needle aspiration and fibrin injection and have had excellent results with no meaningful complications and never a case of aseptic meningitis. We believe this is a safe, highly effective first-line treatment for symptomatic Tarlov cysts.     

The utility of radionuclide myelography and cisternography in the progress of cerebrospinal fluid leaks

Three cases of CSF leaks that did not communicate with the body surface were diagnosed and followed using radionuclide myelography or cisternography. The utility and advantages of this definitive diagnostic method are discussed.     

The utility of radionuclide myelography and cisternography in the progress of cerebrospinal fluid leaks

Three cases of CSF leaks that did not communicate with the body surface were diagnosed and followed using radionuclide myelography or cisternography. The utility and advantages of this definitive diagnostic method are discussed.