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Rationale and Objectives Accurate cerebrospinal fluid (CSF) pressure measurements are critical for diagnosis and treatment of pathologic processes involving the central nervous system. Measuring opening CSF pressure using an analog device takes several minutes, which can be burdensome in a busy practice. The purpose of this study was to compare accuracy of a digital pressure measurement device with analog manometry, the reference gold standard. Secondary purpose included an assessment of possible time savings. Materials and Methods This study was a retrospective, cross-sectional investigation of 71 patients who underwent image-guided lumbar puncture (LP) with opening CSF pressure measurement at a single institution from June 2019 to September 2019. Exclusion criteria were examinations without complete data for both the digital and analog measurements or without recorded needle gauge. All included LPs and CSF pressures were measured with the patient in the left lateral decubitus position, legs extended. Acquired data included (1) digital and analog CSF pressures and (2) time required to measure CSF pressure. Results A total of 56 procedures were analyzed in 55 patients. There was no significant difference in mean CSF pressures between devices: 22.5 cm H2O digitally vs 23.1 analog ( p = .7). Use of the digital manometer resulted in a time savings of 6 min (438 s analog vs 78 s digital, p < .001). Conclusion Cerebrospinal fluid pressure measurements obtained with digital manometry demonstrate comparable accuracy to the reference standard of analog manometry, with an average time savings of approximately 6 min per case.

After teaching in a Christian University for more than 40 years, three professors who are retiring and have received emeritus status reflect on how students have changed over the decades and how they—as professors—have had to adapt to meet the needs of an ever-changing student body. The three professors were asked four questions: (1) how have students changed during the last four decades, (2) how have the professors adapted to meet the changing needs of students, (3) what was one unexpected thing each professor learned once they started teaching, (4) what advice do the professors have for those still teaching in higher education or just starting out in a teaching career, and (5) what can those who are no longer in the classroom pray about for those who are still teaching?

OBJECTIVE Chiari malformation type 1 (CM-1) and spontaneous intracranial hypotension (SIH) are causes of headache in which cerebellar tonsillar ectopia (TE) may be present. An accurate method for differentiating these conditions on imaging is needed to avoid diagnostic confusion. Here, the authors sought to determine whether objective measurements of midbrain morphology could distinguish CM-1 from SIH on brain MRI. METHODS This is a retrospective case-control series comparing neuroimaging in consecutive adult subjects with CM-1 and SIH. Measurements obtained from brain MRI included previously reported measures of brain sagging: TE, slope of the third ventricular floor (3VF), pontomesencephalic angle (PMA), mamillopontine distance, lateral ventricular angle, internal cerebral vein–vein of Galen angle, and displacement of iter (DOI). Clivus length (CL), an indicator of posterior fossa size, was also measured. Measurements for the CM-1 group were compared to those for the entire SIH population (SIHall) as well as a subgroup of SIH patients with > 5 mm of TE (SIHTE subgroup). RESULTS Highly significant differences were observed between SIHall and CM-1 groups in the following measures: TE (mean ± standard deviation, 3.1 ± 5.7 vs 9.3 ± 3.5 mm), 3VF (−16.8° ± 11.2° vs −2.1° ± 4.6°), PMA (44.8° ± 13.1° vs 62.7° ± 9.8°), DOI (0.2 ± 4.1 vs 3.8 ± 1.6 mm), and CL (38.3 ± 4.5 vs 44.0 ± 3.3 mm; all p < 0.0001). Eight (16%) of 50 SIH subjects had TE > 5 mm; in this subgroup (SIHTE), a cutoff value of < −15° for 3VF and < 45° for PMA perfectly discriminated SIH from CM-1 (sensitivity and specificity = 1.0). DOI showed perfect specificity (1.0) in detecting SIH among both groups. No subjects with SIH had isolated TE without other concurrent findings of midbrain sagging. CONCLUSIONS Measures of midbrain sagging, including cutoff values for 3VF and PMA, discriminate CM-1 from SIH and may help to prevent misdiagnosis and unnecessary surgery.

CSF-venous fistulas (CVFs), first described in 2014, are an important cause of spontaneous intracranial hypotension. CVFs can be challenging to detect on conventional anatomic imaging because, unlike other types of spinal CSF leak, they do not typically result in pooling of fluid in the epidural space, and imaging signs of CVF may be subtle. Specialized myelographic techniques have been developed to help with CVF identification, but these techniques are not yet widely disseminated. This article reviews the current understanding of CVFs, emphasizing correlations between venous anatomy and imaging findings as well as potential mechanisms for pathogenesis, and describes current imaging techniques used for CVF diagnosis and localization. These techniques are broadly classified into fluoroscopy-based methods, including digital subtraction myelography and dynamic myelography, and cross-sectional methods, including decubitus CT myelography and MR myelography with intrathecal injection of gadolinium. Knowledge of these various options, including their relative advantages and disadvantages, is critical in the care of patients with spontaneous intracranial hypotension. Investigation is ongoing, and continued advances in knowledge about CVFs as well as in optimal imaging detection are anticipated.

This research essay examined a growing trend in a rural area of the Midwest where PK–12 school districts are partnering with a local university to hire teacher candidates (TCs) as the Teachers of Record (TORs). Many rural school districts are challenged to address the teacher shortage. As a result, many school districts are hiring TCs as the TOR during the TC’s student-teaching experience. Due to the limited research on the topic, this paper aimed to determine if appointing the TC as the TOR was an effective practice. We used three data sources to gauge the perceptions of the TC, the TC’s mentor, and the TC’s administrator. Meeting the needs of partnering districts and providing quality placements for TCs engaged in the culminating field experience can be mutually beneficial for teacher candidates, the school district, and the university.

This study investigated the ability of a redesigned teacher preparation program to effectively meet the needs of teacher candidates and partner school districts. The study examined the effects of the redesigned school of education program on perceptions of teacher candidates, administrators, teachers in partner districts, and faculty members. Findings from school-partnership districts and the school of education were explored. The goal was to use best practices to meet the needs of teacher candidates and provide rich theoretical and clinical experiences in diverse school settings. Findings indicated a change in perceptions of teacher candidates in understanding the importance of equity in the teaching process and of the connection between theory presented in the classroom and application in settings of diverse learners. Teachers and principals indicated an appreciation for renewal through the collaborative experience with teacher candidates during field experiences.

Spontaneous intracranial hypotension (SIH) is a debilitating neurologic condition that is often thought of as separate from idiopathic intracranial hypertension (IIH). The unique case presented here details a spontaneous spinal cerebrospinal fluid (CSF) leak that developed abruptly following a CSF pressure elevating maneuver in a patient with pre-existing intracranial hypertension, raising the possibility of a causative link between the two conditions.A 40-year-old woman with symptomatic IIH developed a dural tear of a thoracic spinal nerve root sleeve during an episode of Valsalva maneuver leading to a CSF leak and development of symptomatic SIH. This was successfully treated with epidural blood and fibrin glue patch and the patient is now symptom-free.The implication of a possible causative link between elevated CSF pressure and subsequent development of dural rupture and SIH raises important questions regarding the pathophysiology of SIH in some cases. Furthermore, it suggests that there could be a potential prophylactic benefit of CSF pressure lowering medications in preventing the development of SIH in patients with IIH.

Retrospective cohort study.We aimed to characterize the treatment patterns and the associated costs in patients with cerebrospinal fluid (CSF) leak after spine procedures in the United States.CSF leak is a common complication after spinal procedures. However, there is a little data regarding the national patterns of treatment choice and the associated health care resource utilization.We utilized the IBM MarketScan Research databases to retrospectively analyze adult US patients diagnosed with CSF leak within 30 days of spine procedures between 2001 and 2018. Treatment prevalence, treatment failure, and health care resource utilization data within 30 days of the CSF leak were collected. A subanalysis was performed on patients who received epidural blood patches (EBP) to better understand health care utilization attributable to this treatment modality.Twenty one thousand four hundred fourteen patients were identified. The most common causes of CSF leak were diagnostic spinal tap (59.2%) and laminectomy/discectomy (18.7%). With regard to treatment prevalence, 40.4% of the patients (n=8651) had conservative medical management, 46.6% (n=9987) received epidural blood patch repair, 9.6% required surgical repair (n=2066), and 3.3% (n=710) had lumbar drain/puncture. Nine hundred sixty-seven (9.7%), 150 (21.1%), and 280 (13.5%) patients failed initial EBP, lumbar drain, and surgery, respectively, and the overall failure rate was 10.9% (n=1397). The median 30-day total cost across all groups was $5,101. Patients who received lumbar drain ($22,341) and surgical repair ($30,199) had higher 30-day median total costs than EBP ($8,140) or conservative management ($17,012). The median 30-day total cost for patients whose EBP failed ($8,179) was substantially greater than those with a successful EBP repair ($3,439).National treatment patterns and costs for CSF leaks were described. When used in the correct patient cohort, EBP has the lower failure rates and costs than comparable alternatives. EBP may be considered more often in situations where conservative management or lumbar drains are currently being used.

Spinal CSF-venous fistulas (CVF) were described in 2014 and are now recognized as an important etiology of spontaneous intracranial hypotension (SIH) 1-3. Surgical ligation is highly effective for treating CVFs4. Given the relatively recent discovery of this entity, long-term follow up on treated cases has not been available, however, surgery has generally been considered definitive treatment. We report four cases of SIH in which CVFs have recurred or developed de novo at a different spinal level following complete surgical ligation of the primary lesion. In all cases, the new CVF was not present on any pre-surgical imaging.

Spontaneous intracranial hypotension (SIH) is a clinical syndrome that is increasingly recognized as an important and treatable secondary cause of headaches. Insight into the condition has evolved significantly over the past decade, resulting in a greater understanding of the underlying pathophysiology, development of new diagnostic imaging tools, and a broadening array of targeted treatment options. This article reviews the clinical presentation and pathogenesis of SIH, discusses the important role of imaging in diagnosis, and describes how imaging guides treatment.

Spinal CSF–venous fistulas are a cause of spontaneous intracranial hypotension that can be difficult to detect on imaging. We describe how the respiratory phase affects the visibility of CSF–venous fistulas during myelography.

This paper examines the impact of diverse clinical field experiences on rural teacher candidates’ perceptions of their ability to effectively teach urban, diverse students. The literature framework supporting the study builds on Nieto’s description of socially-just pedagogy and responsive approach to diversity while meeting national education program standards despite declining resources. Researchers gauged candidates’ perceptions of the impact of working with students from race, language and class backgrounds different from their own. Findings revealed four significant impacts: increasing capacity to use culturally-relevant practice, boosting ability to differentiate for urban learners’ diverse needs, understanding the importance of strong relationships, and raising candidate self-efficacy and desire to teach in diverse schools.

The objective of this study is to determine the rate of inadvertent dural puncture during CT fluoroscopy-guided cervical interlaminar epidural corticosteroid injection. In addition, in a subanalysis, we aim to assess the rate of inadvertent dural puncture superior to C5-C6 occurring during interlaminar epidural corticosteroid injection using CT fluoroscopy guidance because such injections are not performed using conventional fluoroscopy.Images obtained from consecutive CT fluoroscopy-guided cervical interlaminar epidural corticosteroid injections conducted from November 2009 to November 2015 were reviewed. The following information was recorded: the presence of inadvertent dural puncture, the level of the cervical interlaminar space, approach laterality (left or right), anteroposterior spinal canal diameter, and the presence of a trainee. Two-tailed Fisher exact tests were used for assessment of categoric variables, and t tests were used for continuous variables.A total of 974 cervical interlaminar epidural corticosteroid injections were identified in 728 patients. Inadvertent dural punctures were identified in association with 1.4% (14/974) of these injections; all punctures were recognized during the procedure. Needle placements were performed at every cervical level (C1-C2 through C7-T1). The highest rate of dural puncture (2.8%) occurred at C5-C6. No dural punctures occurred superior to C5-C6 (16.6% of cases). The complication rate was 0.4%. Only greater anteroposterior spinal canal diameter was associated with increased dural puncture rates (p = 0.049).CT fluoroscopy-guided cervical interlaminar epidural corticosteroid injections were performed at all levels throughout the cervical spine. A very low complication rate and a minimal rate of inadvertent dural puncture were noted, similar to previously reported rates for conventional fluoroscopy-guided injections limited to the lower cervical spine only.

The objective of our study was to determine whether the presence of individual imaging signs of spontaneous intracranial hypotension (SIH) is correlated with increasing duration of headache symptoms. Of particular interest is the relationship of symptom duration to dural enhancement because it is the most commonly identified imaging sign in patients with SIH.Eighty-nine patients with SIH who underwent pretreatment brain MRI and total-spine CT myelography and whose medical record included data on the duration of clinical symptoms were included in this cross-sectional retrospective study. Brain imaging was reviewed for the presence of dural enhancement, brain sagging, and the "venous distention" sign. CT myelograms were assessed for CSF leak. If present, a leak was subcategorized as a high-flow or low-flow leak. Differences in headache duration between subjects with and those without individual imaging signs were compared.Subjects without dural enhancement on brain MRI had a longer average duration of symptoms than those with dural enhancement present (average symptom duration: 45.3 ± 59.0 [SD] vs 15.1 ± 33.0 weeks, respectively; p = 0.002). No difference in symptom duration was observed between subjects whose MRI studies showed and those whose MRI studies did not show brain sagging (p = 0.10) or the venous distention sign (p = 0.21). The presence of a CSF leak on CT myelography was not associated with symptom duration (p = 0.56) except in the subgroup of patients with low-flow leaks.Increasing symptom duration in SIH is associated with decreased prevalence of abnormal dural enhancement on brain MRI. Because dural enhancement is considered a hallmark imaging feature of this condition, its absence may exacerbate the problem of underdiagnosis in chronic cases of SIH.

Spontaneous intracranial hypotension (SIH) is a clinical syndrome that is increasingly recognized as an important and treatable secondary cause of headaches. Insight into the condition has evolved significantly over the past decade, resulting in a greater understanding of the underlying pathophysiology, development of new diagnostic imaging tools, and a broadening array of targeted treatment options. This article reviews the clinical presentation and pathogenesis of SIH, discusses the important role of imaging in diagnosis, and describes how imaging guides treatment.

Methods Dose rates from 30 patients, treated over a 3-year period (2016–2018) were measured post therapy in contact with the patients’ upper abdomen and at distances of 0.3 m and 1 m. Dose rates were compared with theoretical predictions and used as model inputs for calculating radiation doses received by family members and carers based on interaction patterns previously described in the literature. Results The average dose rate per activity from SIRT patients were:- In contact: 29 ± 23 µSv.h−1.GBq−1; 0.3 m: 4.1 ± 2.34 µSv.h−1.GBq−1 and 1 m: 0.59 ± 0.42 µSv.h−1.GBq−1. Dose rates measured at 0.3 and 1 m followed a predictable distribution. Estimated doses based on proximity models demonstrated restrictions to be advisable, depending on the administered activity, considering the dose constraint and limit of 0.3 and 1 mSv, respectively, employed within the EU. Conclusions In accordance with local dose constraints, and depending on administered activities, radiation protection precautions may be necessary for those individuals in regular contact with patients who have receive 90Y SIRT. A radiation protection precautions calculator has been devised to offer personalised instructions taking into account the administered activity and proximity models.

Objectives Spontaneous intracranial hypotension (SIH) is a pathologic state of low CSF volume caused by a CSF to venous fistula or CSF leak. It is diagnosed based on symptoms, imaging, and CSF pressure but is often a diagnostic challenge because no single test is highly sensitive. Physician-induced changes in CSF volume may result in changes in patient symptoms, as has been shown with idiopathic intracranial hypertension (IIH). The purpose of this study is to determine the sensitivity of CSF volume provocation maneuvers in the diagnosis of SIH. Patients and Methods We reviewed consecutive patients that underwent lumbar puncture from January 2015 to January 2017. Patients were included if they met ICHD3 criteria for SIH and CSF volume provocation maneuvers were performed. Cases were considered concordant if there was improvement of symptoms with addition of CSF. Results 1084 patients underwent 2250 CT-guided lumbar punctures from January 2015 to January 2017. 92 patients with SIH were identified and 62 of these patients underwent CSF volume provocation maneuvers. 58% (36/62) had concordant lumbar puncture encounters with symptom improvement upon addition of artificial CSF. Conclusion CSF volume provocation maneuvers demonstrate 58% sensitivity for identifying patients with SIH, better than those reported for CSF opening pressure and myelography. A positive symptomatic response to CSF volume provocation maneuvers was independent of the other objective tests used for SIH and may aid in the often-challenging diagnostic workup of these patients. Future prospective case-controlled studies are needed.

Spontaneous intracranial hypotension is caused by spinal CSF leaks, but the site of the leak is not always detected on spinal imaging. We report on the additional value of decubitus positioning during CT myelography in enhancing the detection of subtle leaks.

BACKGROUND Cerebrospinal fluid-venous fistula (CVF) is a recently described cause of spontaneous intracranial hypotension (SIH). Surgical ligation of CVF has been reported, but clinical outcomes are not well described. OBJECTIVE To determine the clinical efficacy of surgical ligation for treatment of CVF. METHODS Outcomes metrics were collected in this prospective, single-arm, cross-sectional investigation. Inclusion criteria were as follows: diagnosis of SIH, demonstration of CVF on myelography, and surgical treatment of CVF. Pre- and postoperative headache severity was assessed with the Headache Impact Test (HIT-6), a validated headache scale ranging from 36 (asymptomatic) to 78 (most severe). Patient satisfaction with treatment was measured with Patient Global Impression of Change (PGIC). RESULTS Twenty subjects were enrolled, with mean postoperative follow-up at 16.0 ± 9.7 mo. All CVFs were located in the thoracic region (between T4 and T12). Pretreatment headache severity was high (mean HIT-6 scores 65 ± 6). Surgical treatment resulted in marked improvement in headache severity (mean HIT-6 change of -21 ± -9, mean postoperative HIT-6 of 44 ± 8). Of subjects with baseline headache scores in the most severe category, 83% showed a major improvement in severity (transition to the lowest 2 severity categories) after surgery. All subjects (100%) reported clinically significant levels of satisfaction with treatment (PGIC score 6 or 7); 90% reported the highest level of satisfaction. There were no short- or long-term complications or 30-d readmissions. CONCLUSION Surgical ligation is highly effective for the treatment of SIH due to CVF. Larger controlled trials with longer follow-up period are indicated to better assess its long-term efficacy and safety profile.

BACKGROUND AND PURPOSE: Epidural blood patch treatment of spontaneous intracranial hypotension arising from ventral CSF leaks can be difficult secondary to challenges in achieving ventral spread of patching material. The purpose of this study was to determine the technical success rates and safety profile of direct needle placement into the ventral epidural space via a posterior transforaminal approach. MATERIALS AND METHODS: We retrospectively reviewed consecutive CT fluoroscopy–guided epidural blood patches from June 2013 through July 2015. Cases were included if a posterior transforaminal approach was taken to place the needle directly in the ventral epidural space. Rates of technical success (defined as contrast in the spinal canal ventral epidural space) and optimal epidurogram (defined as contrast spreading into or beyond the middle third of the spinal canal ventral epidural space) were determined. Factors influencing these rates were assessed. All complications, inadvertent intravascular injections, and intrathecal punctures were recorded. RESULTS: A total of 72 ventral epidural blood patches were identified; immediate technical success was achieved in 95.8% and an optimal epidurogram in 47.2%. Needle position within the spinal canal ventral epidural space was associated with obtaining an optimal epidurogram (P = .005). Inadvertent intravascular injection was identified in 29.3% of cases, but all were venous. There were no inadvertent intrathecal punctures or complications. CONCLUSIONS: Direct needle placement in the ventral epidural space via a transforaminal approach for treatment of ventral CSF leaks has an excellent technical success rate and safety profile. This technique can be considered as a treatment option in selected patients with ventral CSF leaks for whom traditional techniques are unsuccessful.

The objective of this study was to summarize the available literature describing the presentation, diagnostic evaluation, and management for adults with Type 1 and Type 2 split spinal cord malformations. A review of the literature was performed using the CINAHL, PubMed, Embase, and Web of Science database, alongside all associated bibliographies, to include studies describing Type 1 and Type 2 split cord malformations diagnosed in patients above the age of 18. All relevant studies of split cord malformations were included, regardless of the year published and terminology used to describe the dysraphism. Clinical case series (≥ 2 patients), cohort studies, and review articles comprising adult patients with radiographically diagnosed diastematomyelia, diplomyelia, or dimyelia were included (Class of Evidence I-IV). A total of 17 unique articles, describing 146 unique adult spinal cord malformation subjects, were included. The most common associated condition was tethered cord syndrome (59.8 %). Operative management for symptomatic split cord malformation was performed in 72.3 % of cases. For those with preoperative neurologic deficits, operative management resulted in symptomatic improvement in 96.6 %, compared to 0 % conservative management (p < 0.05). For those with pain alone, operative management resulted in improvement of 91.1 %, compared to 12.5 % conservative management (p < 0.05). To date, this is the only literature review to include all split cord malformations (SCM Types I and II) presenting in adulthood, with clinical characteristics, associated conditions, and long-term treatment outcomes.

The purpose of this study was to assess the rate of inadvertent injection into the retrodural space of Okada during CT fluoroscopy-guided interlaminar epidural steroid injection in the cervical spine.Images from cases of cervical interlaminar epidural steroid injection under CT fluoroscopic guidance performed at a single institution between November 2009 and November 2015 were obtained and reviewed. For all cases, the following information was recorded: presence or absence of contrast material within the Okada space, cervical anatomic level at which the procedure was performed, laterality of approach, trainee presence, and years of proceduralist experience. Two-tailed chi-square tests were used to assess categoric variables, and t tests were performed to assess for continuous variables predictive of nontarget injection.A total of 974 CT fluoroscopy-guided cervical interlaminar epidural steroid injections were identified in 728 patients. The presence of contrast material in the retrodural space of Okada was identified in 2.9% of cases (28/974). All cases of inadvertent injection were identified and corrected intraprocedurally. The greatest rate of inadvertent injection (4.6% [18/389]) occurred at C5-6. No variables predictive of inadvertent injection into the Okada space were identified. There was a 0.4% (4/974) complication rate, and all complications were minor.We identified a 2.9% rate of unintended injection into the retrodural space of Okada during cervical interlaminar epidural steroid injection. If unrecognized, these nontarget injections can result in treatment failure in a subset of patients who undergo cervical interlaminar epidural steroid injection. Future study is warranted to assess the rate of inadvertent Okada injection under conventional fluoroscopy and to compare the rates of detection between the two imaging-guided modalities.

Objective To discuss common myths and misperceptions about spontaneous intracranial hypotension (SIH), focusing on common issues related to diagnosis and treatment, and to review the evidence that contradicts and clarifies these myths. Background Recognition of SIH has increased in recent years. With increasing recognition, however, has come an increased demand for management by neurologists and headache specialists, some of whom have little prior experience with the condition. This dearth of practical experience, and lack of awareness of recent investigations into SIH, produces heterogeneity in diagnostic and treatment pathways, driven in part by outdated, confusing, or unsubstantiated conceptions of the condition. We sought to address this heterogeneity by identifying 10 myths and misperceptions that we frequently encounter when receiving referrals for suspected or confirmed SIH, and to review the literature addressing these topics. Methods Ten topics relevant to diagnosis and treatment SIH were generated by the authors. A search for studies addressing SIH was conducted using PubMed and EMBASE, limited to English language only, peer reviewed publications from inception to 2018. Individual case reports were excluded. The resulting studies were reviewed for relevance to the topics in question. Results The search generated 557 studies addressing SIH; 75 case reports were excluded. Fifty-four studies were considered to be of high relevance to the topics addressed, and were included in the data synthesis. The topics are presented in the form of a narrative review. Conclusions The understanding of SIH has evolved over the recent decades, leading to improvements in knowledge about the pathophysiology of the condition, diagnostic strategies, and expanded treatments. Awareness of these changes, and dispelling outdated misconceptions about SIH, is critical to providing appropriate care for patients and guiding future investigations going forward.

A 58-year-old woman with a calcified disk extrusion causing severe spinal stenosis underwent T8 to T9 diskectomy and spinal fusion. A postoperative pseudomeningocele was treated with lumbar drain and fibrin glue. Performed for persistent right pleural effusion, CT myelogram failed to show communication between the cerebrospinal fluid (CSF) and pleural space--even on 2-hour delayed images. Subsequent 111In-DTPA cisternogram clearly demonstrated CSF leakage into the right pleural space at 2 hours, and surgical repair yielded good results. Radionuclide cisternography is a highly useful method to detect CSF leak, especially when it is occult on CT yet suspected clinically.

CSF-venous fistula is a recently reported cause of spontaneous intracranial hypotension that may occur in the absence of myelographic evidence of CSF leak. Information about this entity is currently very limited, but it is of potential importance given the large percentage of cases of spontaneous intracranial hypotension associated with negative myelography findings. We report 3 additional cases of CSF-venous fistula and describe the “hyperdense paraspinal vein” sign, which may aid in its detection.

The objective of this study is to describe the anatomic and imaging features of CSF venous fistulas, which are a recently reported cause of spontaneous intracranial hypotension (SIH).We retrospectively reviewed the records of patients with SIH caused by CSF venous fistulas who received treatment at our institution. The anatomic details of each fistula were recorded. Attenuation of the veins involved by the fistula was compared with that of adjacent control veins on CT myelography (CTM). Visibility of the CSF venous fistula on CTM and a modified conventional myelography technique we refer to as dynamic myelography was also compared.Twenty-two cases of CSF venous fistula were identified. The fistulas were located between T4 and L1. Ninety percent occurred without a concurrent epidural CSF leak. In most cases (82%), the CSF venous fistula originated from a nerve root sleeve diverticulum. On CTM, the abnormal veins associated with the CSF venous fistula were seen in a paravertebral location in 45% of cases, centrally within the epidural venous plexus in 32%, and lateral to the spine in 23%. Differences in attenuation between the fistula veins and the control veins was highly statistically significant (p0.0001), with a threshold of 70 HU perfectly discriminating fistulas from normal veins in our series. When both CTM and dynamic myelography were performed, the fistula was identified on both modalities in 88% of cases.CSF venous fistulas are an important cause of SIH that can be detected on both CTM and dynamic myelograph y and may occur without an epidural CSF leak. Familiarity with the imaging characteristics of these lesions is critical to providing appropriate treatment to patients with SIH.

The purpose of this study is to provide an update on recent developments in the understanding, diagnosis, and treatment of spontaneous intracranial hypotension (SIH). SIH is an important cause of headaches caused by spinal cerebrospinal fluid (CSF) leaks, with an increasingly broad spectrum of clinical presentations and diagnostic findings. A simple conception of the condition as being defined by the presence of low CSF pressure is no longer sufficient or accurate. A number of etiologies for spinal CSF leaks have been identified, including the recent discovery of CSF-venous fistulas, and these various etiologies may require different diagnostic and therapeutic pathways in order to affect a cure. Familiarity with the spectrum of presentations and causes of SIH is critical to accurate and timely diagnosis and management. Challenges exist in both diagnosis and treatment, and require understanding of the underlying pathogenesis of the condition in order to appropriately select testing and treatment. Prospective studies are needed going forward in order to inform workup and guide treatment decisions.

Object Cerebrospinal fluid leaks due to unrecognized durotomy during spinal surgery are often managed with a second surgery for dural closure. CT-guided percutaneous patching targeted to the dural defect offers an alternative to surgery since it can be performed in a minimally invasive fashion without the need for general anesthesia. This case series describes the authors' experience using targeted CT-guided percutaneous patching to repair incidental durotomies incurred during spinal surgery. Methods This investigation is a retrospective case series involving patients who underwent CT-guided percutaneous patching of surgical incidental durotomies and were referred between January 2007 and June 2013. Their presenting clinical history, myelographic findings, and clinical outcomes, including the need for eventual surgical duraplasty, were reviewed. Results Nine cases were identified, including 7 durotomies incurred during lumbar discectomy, one due to a medial transpedicular screw breach, and one incurred during vertebrectomy for spinal osteosarcoma. All patients who had favorable outcomes with percutaneous intervention alone had 2 common features: dural defect of 4 mm or smaller and absence of a pseudomeningocele. Patients with CSF leaks complicated by pseudomeningocele and those with a dural defect of 6 mm or more all required eventual surgical management. Conclusions The authors' results suggest that findings on CT myelography may help predict which patients with postsurgical durotomy can be treated with percutaneous intervention. In particular, CT-guided patching may be more likely to be successful in those patients with dural defects of less than 5 mm and without pseudomeningocele. In patients with larger dural defects or pseudomeningoceles, percutaneous blood patching alone is unlikely to be successful.