Uncommon Manifestations of Intervertebral Disk Pathologic Conditions.

Beyond the familiar disk herniations with typical clinical features, intervertebral disk pathologic conditions can have a wide spectrum of imaging and clinical manifestations. The goal of this review is to illustrate and discuss unusual manifestations of intervertebral disk pathologic conditions that radiologists may encounter, including disk herniations in unusual locations, those with atypical imaging features, and those with uncommon pathophysiologic findings. Examples of atypical disk herniations presented include dorsal epidural, intradural, symptomatic thoracic (including giant calcified), extreme lateral (retroperitoneal), fluorine 18 fluorodeoxyglucose-avid, acute intravertebral (Schmorl node), and massive lumbar disk herniations. Examples of atypical pathophysiologic conditions covered are discal cysts, fibrocartilaginous emboli to the spinal cord, tiny calcified disks or disk-level spiculated osteophytes causing spinal cerebrospinal fluid (CSF) leak and intracranial hypotension, and pediatric acute calcific discitis. This broad gamut of disease includes a variety of sizes of disk pathologic conditions, from the tiny (eg, the minuscule calcified disks causing high-flow CSF leaks) to the extremely large (eg, giant calcified thoracic intradural disk herniations causing myelopathy). A spectrum of clinical acuity is represented, from hyperacute fibrocartilaginous emboli causing spinal cord infarct, to acute Schmorl nodes, to chronic intradural herniations. The entities included are characterized by a range of clinical courses, from the typically devastating cord infarct caused by fibrocartilaginous emboli, to the usually spontaneously resolving pediatric acute calcific discitis. Several conditions have important differential diagnostic considerations, and others have relatively diagnostic imaging findings. The pathophysiologic findings are well understood for some of these entities and poorly defined for others. Radiologists' knowledge of this broad scope of unusual disk disease is critical for accurate radiologic diagnoses. Online supplemental material is available for this article. (©)RSNA, 2016.

Intracranial Gadolinium Deposition after Contrast-enhanced MR Imaging.

PURPOSE: To determine if repeated intravenous exposures to gadolinium-based contrast agents (GBCAs) are associated with neuronal tissue deposition. MATERIALS AND METHODS: In this institutional review board-approved single-center study, signal intensities from T1-weighted magnetic resonance (MR) images and postmortem neuronal tissue samples from 13 patients who underwent at least four GBCA-enhanced brain MR examinations between 2000 and 2014 (contrast group) were compared with those from 10 patients who did not receive GBCA (control group). Antemortem consent was obtained from all study participants. Neuronal tissues from the dentate nuclei, pons, globus pallidus, and thalamus of these 23 deceased patients were harvested and analyzed with inductively coupled plasma mass spectrometry (ICP-MS), transmission electron microscopy, and light microscopy to quantify, localize, and assess the effects of gadolinium deposition. Associations between cumulative gadolinium dose, changes in T1-weighted MR signal intensity, and ICP-MS-derived tissue gadolinium concentrations were examined by using the Spearman rank correlation coefficient (ρ). RESULTS: Compared with neuronal tissues of control patients, all of which demonstrated undetectable levels of gadolinium, neuronal tissues of patients from the contrast group contained 0.1-58.8 µg gadolinium per gram of tissue, in a significant dose-dependent relationship that correlated with signal intensity changes on precontrast T1-weighted MR images (ρ = 0.49-0.93). All patients in the contrast group had relatively normal renal function at the time of MR examination. Gadolinium deposition in the capillary endothelium and neural interstitium was observed only in the contrast group. CONCLUSION: Intravenous GBCA exposure is associated with neuronal tissue deposition in the setting of relatively normal renal function. Additional studies are needed to investigate the clinical significance of these findings and the generalizability to other GBCAs. Online supplemental material is available for this article.

Neuroimaging Findings in Cardiac Myxoma Patients: A Single-Center Case Series of 47 Patients.

BACKGROUND AND PURPOSE: Cardiac myxomas can present with a myriad of neurological complications including stroke, cerebral aneurysm formation and metastatic disease. Our study had two objectives: (1) to describe the neuroimaging findings of patients with cardiac myxomas and (2) to examine the relationship between a history of embolic complications secondary to myxoma and intracranial aneurysm formation, hemorrhage and metastatic disease. We hypothesized that patients who present with embolic complications related to myxoma would be more likely to have such complications. MATERIALS AND METHODS: We searched our institutional database for all patients with pathologically proven cardiac myxomas from 1995 to 2014 who received neuroimaging. Neuroimaging findings were categorized as acute ischemic stroke, intracerebral hemorrhage, oncotic aneurysm, and cerebral metastasis. Cardiac myxoma patients were divided into those presenting with embolic complications (i.e. lower extremity emboli or cerebral emboli) and those presenting with non-embolic complications prior to surgical resection of the myxoma. The prevalence of intracranial hemorrhage, myxomatous aneurysm formation, and cerebral metastases was compared in myxoma patients presenting with and without embolic complications using a Chi-squared test. RESULTS: Forty-seven consecutive patients were included in this study. Sixteen patients (34.0%) had imaging evidence of acute ischemic stroke. Of these, 13 had acute ischemic strokes directly attributed to the cardiac myxoma (27.7%) and 3 had acute ischemic strokes secondary to causes other than myxoma (6.4%). Seven patients (14.9%) had aneurysms. Two patients (4.3%) had parenchymal metastatic disease on long-term imaging. Fourteen patients (29.8%) presented with ischemic symptoms that were attributed to cardiac myxoma (1 with lower extremity ischemia, 1 with lower extremity ischemia and ischemic stroke, and 12 with ischemic stroke). Patients presenting with embolic complications related to the myxoma (ischemic stroke or lower extremity ischemia) were more likely to have imaging evidence of intracranial hemorrhage (21.4 vs. 3.0%, p = 0.09), oncotic aneurysm (35.7 vs. 6.1%, p = 0.03), and cerebral metastasis (14.3 vs. 0.0%, p = 0.07) on follow-up imaging. CONCLUSIONS: Ischemic stroke and intracranial oncotic aneurysm were found in a substantial proportion of cardiac myxoma patients undergoing neuroimaging. Patients presenting with embolic complications of cardiac myxoma are more likely to have intracranial hemorrhage, intracranial oncotic aneurysms, and cerebral metastatic disease.

A practice audit of CT-guided injections of pars interarticularis defects in patients with axial low back pain: a primer for further investigation.

OBJECTIVE: To assess whether computed tomography (CT)-guided injections of local anesthetic and corticosteroid into chronic lumbar pars interarticularis defects may identify and provide benefit to a cohort of patients where the pars defects act as a primary axial pain generator. DESIGN: Retrospective practice audit. SETTING: Single academic radiology pain management practice. PATIENTS: 59 consecutive patients undergoing CT-guided injections of lumbar pars defects. METHODS: Patients were assessed with a pain numerical rating scale (NRS, 0-10) and Roland-Morris disability questionnaire (R-M) prior to injection and at 2 weeks and 2 months follow-up. For categorical outcomes, successful pain relief response was defined as either ≥50% reduction in NRS or pain 0/10; functional response was defined as ≥40% reduction in R-M score. Continuous outcomes (mean NRS, R-M scores) were assessed for significant change following injection. RESULTS: For categorical outcomes, 37.9% of patients were responders at 2 months' follow-up; 20.7 % had complete relief of index pain. For functional recovery, 34.5% were responders at 2 months. Using continuous outcomes, mean NRS was 5.4 ± 2.1 prior to injection and 3.6 ± 2.6 at 2 months (P < 0.0001). Mean R-M score was 11.7 ± 6.0 prior to injection and 9.0 ± 5.4 at 2 months (P = 0.001). There were no complications. CONCLUSIONS: This practice audit suggests that in patients with axial low back pain and chronic pars defects, the pars defects may be implicated as the primary axial pain generator in a small subgroup of patients. Local deposition of corticosteroids into the pars defect may provide significant pain relief in one out of three patients, and complete relief in one out of five patients. This data suggest there may be benefit to pursuing randomized controlled trials of pars injections comparing steroid injection with placebo.

The effectiveness of repeat lumbar transforaminal epidural steroid injections.

OBJECTIVE: The aim of this study was to determine 1) if repeat lumbar transforaminal epidural steroid injections (TFESIs) resulted in recovery of pain relief, which has waned since an index injection, and 2) if cumulative benefit could be achieved by repeat injections within 3 months of the index injection. DESIGN: Retrospective observational study with statistical modeling of the response to repeat TFESI. SETTING: Academic radiology practice. PATIENTS: Two thousand eighty-seven single-level TFESIs were performed for radicular pain on 933 subjects. Subjects received repeat TFESIs >2 weeks and <1 year from the index injection. METHODS: Hierarchical linear modeling was performed to evaluate changes in continuous and categorical pain relief outcomes after repeat TFESI. Subgroup analyses were performed on patients with <3 months duration of pain (acute pain), patients receiving repeat injections within 3 months (clustered injections), and in patients with both acute pain and clustered injections. RESULTS: Repeat TFESIs achieved pain relief in both continuous and categorical outcomes. Relative to the index injection, there was a minimal but statistically significant decrease in pain relief in modeled continuous outcome measures with subsequent injections. Acute pain patients recovered all prior benefit with a statistically significant cumulative benefit. Patients receiving clustered injections achieved statistically significant cumulative benefit, of greater magnitude in acute pain patients. CONCLUSION: Repeat TFESI may be performed for recurrence of radicular pain with the expectation of recovery of most or all previously achieved benefit; acute pain patients will likely recover all prior benefit. Repeat TFESIs within 3 months of the index injection can provide cumulative benefit.

CT-guided cervical transforaminal epidural steroid injections: technical insights.

Recent studies have described the safety and efficacy of computed tomography (CT)-guided cervical transforaminal epidural steroid injections with both the anterolateral and posterior approach. Although fluoroscopy is the most common form of image guidance for these procedures, CT guidance offers many advantages. However, some key features of CT guidance in these procedures need to be considered to ensure safe and technically successful outcomes.

An audit of transforaminal epidural steroid injections without sedation: low patient dissatisfaction and low vasovagal rates.

OBJECTIVE: To assess frequency of sedation in transforaminal epidural steroid injections (TFESI) and to analyze patient dissatisfaction and vasovagal rates. DESIGN: Retrospective audit over a 6-year period, January 1, 2006-December 31, 2011. SETTING: Single academic center radiology pain management practice. SUBJECTS: Four thousand four hundred thirty-two patients undergoing 6,878 consecutive TFESI. OUTCOME MEASURES: Frequency of sedation for TFESI was assessed. Vasovagal and patient dissatisfaction rates were assessed, the latter by patients' responses to two follow-up survey questions at 2 weeks postprocedure. RESULTS: Six thousand eight hundred seventy-eight TFESI were performed, of which only 0.1% (N = 7) were performed with sedation. Only 0.4% (N = 28) of TFESI were complicated by vasovagal reaction. Seventy-two percent (N = 4,980) of nonsedated patients responded to the survey. Overall medical care in the nonsedated was rated as: excellent 51%, very good 30%, good 15%, fair 3%, and poor 1%. Ninety-five percent confidence interval (CI) for the 3.9% of the nonsedated patients who rated their care at best "fair" was (3.3, 4.4%). Likelihood of referring friends/family members in nonsedated patients was: definitely 53%, probably 28%, uncertain 16%, probably not 3%, definitely not 0.2%. Ninety-five percent CI for the 3.2% of the nonsedated patients who would at best "probably not refer" their friends/family was (2.7, 3.7%). CONCLUSIONS: In our radiology pain management practice, sedation was rarely utilized for TFESI. A small minority of nonsedated patients rated their care at best fair and would at best probably not refer friends/family members. TFESI can be performed without sedation with low patient dissatisfaction and low vasovagal rates.

Clinical effectiveness of single lumbar transforaminal epidural steroid injections.

OBJECTIVES: To assess the clinical effectiveness of single lumbar transforaminal epidural steroid injections (TFESIs) in subjects with radicular pain with or without radiculopathy. DESIGN: Retrospective observational series. SETTING: Single academic radiology pain management practice. SUBJECTS: Two thousand twenty-four subjects undergoing single lumbar TFESIs at the L4-5, L5-S1, or S1 neural foramina. METHODS / OUTCOME MEASURES: Subjects were assessed with a pain numerical rating scale (NRS, 0-10) and Roland-Morris disability questionnaire (R-M, 23-point Deyo modification) prior to TFESI and at 2 weeks and 2 months follow-up. Successful pain relief (responders) was defined as either ≥50% reduction in NRS or pain 0/10; functional success was defined as ≥40% reduction in R-M score. RESULTS: There were statistically significant (P < 0.0001) reductions in mean NRS and R-M scores at 2 weeks and 2 months postinjection. For NRS, 40.9% were responders at 2 weeks and 45.6% at 2 months. For R-M, 31.9% were responders at 2 weeks and 41.3% at 2 months. The proportion of responders for NRS and R-M was higher when there was <3 months of pain (odds ratio 2-month NRS = 2.42 [95% confidence interval: 1.82, 3.24], odds ratio 2-month R-M = 2.61 [1.96, 3.48]). For subjects with <3 months of pain, the proportion of responders was 62.4% (56.5, 68.3%) for NRS and 59.3% (53.3, 65.3%) for R-M scores. CONCLUSIONS: This retrospective observational study suggests TFESIs are clinically effective in the treatment of lumbar radicular pain. Subjects with a shorter duration of pain are more likely to achieve a successful outcome.

The noninferiority of the nonparticulate steroid dexamethasone vs the particulate steroids betamethasone and triamcinolone in lumbar transforaminal epidural steroid injections.

OBJECTIVE: To assess whether a nonparticulate steroid (dexamethasone, 10 mg) is less clinically effective than the particulate steroids (triamcinolone, 80 mg; betamethasone, 12 mg) in lumbar transforaminal epidural steroid injections (TFESIs) in subjects with radicular pain with or without radiculopathy. DESIGN: Retrospective observational study with noninferiority analysis of dexamethasone relative to particulate steroids. SETTING: Single academic radiology pain management practice. SUBJECTS: Three thousand six hundred forty-five lumbar TFESIs at the L4-5, L5-S1, or S1 neural foramina, performed on 2,634 subjects. METHODS/OUTCOME MEASURES: Subjects were assessed with a pain numerical rating scale (NRS, 0-10) and Roland-Morris disability questionnaire (R-M) prior to TFESI, and at 2 weeks and 2 months follow-up. For categorical outcomes, successful pain relief was defined as either ≥50% reduction in NRS or pain 0/10; functional success was defined as ≥40% reduction in R-M score. Noninferiority analysis was performed with δ = -10% as the limit of noninferiority. Continuous outcomes (mean NRS, R-M scores) were analyzed for noninferiority with difference bounds of 0.3 for NRS scores and 1.0 for R-M scores. RESULTS: With categorical outcomes, dexamethasone was demonstrated to be noninferior to the particulate steroids in pain relief and functional improvement at 2 months. Using continuous outcomes, dexamethasone was demonstrated to be superior to the particulate steroids in both pain relief and functional improvement at 2 months. CONCLUSION: This retrospective observational study reveals no evidence that dexamethasone is less effective than particulate steroids in lumbar TFESIs performed for radicular pain with or without radiculopathy.

The role of digital subtraction myelography in the diagnosis and localization of spontaneous spinal CSF leaks.

OBJECTIVE: The objective of our study was to review the clinical utility of digital subtraction myelography for the diagnosis of spinal CSF leaks in patients with spontaneous intracranial hypotension (SIH) and those with superficial siderosis. MATERIALS AND METHODS: Procedure logs from 2007 to 2011 were reviewed to identify cases in which digital subtraction myelography was performed to diagnose spinal CSF leaks. Electronic medical records were reviewed to obtain information regarding diagnosis and outcome. For patients to be included in the study, preprocedural spinal MRI had to show an extradural fluid collection spanning more than one vertebral level and postmyelographic CT had to confirm the presence of an active CSF leak. If digital subtraction myelography successfully showed the site of the CSF leak, the location was documented. RESULTS: Eleven patients (seven men and four women; mean age, 49.0 years) underwent digital subtraction myelography during the study period. Six patients had SIH and five patients had superficial siderosis. The extradural fluid collection on spinal MRI averaged a length of 15.5 vertebral levels. Digital subtraction myelography successfully showed the site of the CSF leak in nine of the 11 patients, and all of the dural tears were located in the thoracic spine between T3 and T11. CONCLUSION: Digital subtraction myelography is a valuable diagnostic tool for the localization of rapid spinal CSF leaks and should be considered in patients who are clinically suspected to have a dural tear that is accompanied by a longitudinally extensive extradural fluid collection on spinal MRI.

Use of Self-Collected Saliva Samples for the Detection of SARS-CoV-2.

OBJECTIVE: Using a US Food and Drug Administration (FDA) emergency use authorization (EUA) reverse transcription polymerase chain reaction (RT-PCR) method, we examined the analytic performance accuracy of saliva specimens as compared to nasopharyngeal (NP) specimens in symptomatic patients. Correlation between test results and symptoms was also evaluated. METHODS: Over a 5-week period in 2020, 89 matched saliva and nasopharyngeal swabs were collected from individuals exhibiting symptoms consistent with SARS-CoV-2. Specimens were tested with an FDA EUA-approved RT-PCR method, and performance characteristics were compared. RESULTS: The concordance rate between saliva and nasopharyngeal testing was 93.26%. The mean cycle threshold value of saliva when compared to the NP specimen was 3.56 cycles higher. As compared to NP swab, saliva testing demonstrates acceptable agreement but lower sensitivity. CONCLUSION: When compared to a reference method using NP swabs, the use of saliva testing proved to be a reliable method. Self-collected saliva testing for SARS-CoV-2 allows for a viable option when trained staff or collection materials are in short supply.

Performance Accuracy of a Laboratory-Developed Real-Time RT-PCR Method for Detection of SARS-CoV-2 in Self-Collected Saliva Specimens.

OBJECTIVE: The ongoing COVID-19 pandemic caused by SARS-CoV-2 has challenged diagnostic laboratories to re-examine traditional methods for collecting specimens and sample types used in molecular testing. Our goal was to demonstrate that saliva can be used for detecting SARS-CoV-2 and correlates well with established molecular methods using nasopharyngeal (NP) swabs. METHODS: We examined use of a saliva collection device in conjunction with a laboratory-developed real-time reverse transcription-polymerase chain reaction (LDPCR) method for detecting SARS-CoV-2 in a symptomatic population and compared results with 2 US Food and Drug Administration (FDA)-approved methods (emergency use authorization [EUA]) that use specimens from NP swabs. RESULTS: The sensitivity of LDPCR compared with the reference methods was 75.0% (21/28); specificity, 98.1% (104/106). When cycle threshold values were compared between paired specimens using the LDPCR and a EUA reverse transcription PCR method, both targeting the open-reading frame gene, the mean value for saliva was 4.66 cycles higher than for NP specimens. CONCLUSION: Use of self-collected saliva in conjunction with an LDPCR for SARS-CoV-2 compared favorably with 2 FDA EUA methods using NP swabs. The use of an alternative sample type and assay method will aid in expanding the availability of testing during the ongoing COVID-19 pandemic.

Addressing the Challenge of COVID-19: One Health Care Site's Leadership Response to the Pandemic.

The coronavirus disease 2019 (COVID-19) pandemic created an extremely disruptive challenge for health care leaders that required a rapid, dynamic, and innovative response. The purpose of this manuscript is to share the leadership actions and decisions at Mayo Clinic in Florida during the first 6 months of the pandemic (February to July 2020). We note 4 strategies that contributed to an effective response: (1) leverage experience with disaster preparedness and mobilize regional and national networks; (2) use surge models to anticipate and to address supply chain issues as well as practical and financial effects of the pandemic; (3) adapt creatively to establish new safety and procedural protocols in various areas for various populations; and (4) communicate timely information effectively and be the common source of truth. Mayo Clinic in Florida was able to address the surges of patients with COVID-19, to provide ongoing tertiary care, and to restore function within the first 6 months with new, strengthened practices and protocols.

Prevalence of SARS-CoV-2 Antibodies in a Multistate Academic Medical Center.

OBJECTIVE: To estimate the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in health care personnel. METHODS: The Mayo Clinic Serology Screening Program was created to provide a voluntary, two-stage testing program for SARS-CoV-2 antibodies to health care personnel. The first stage used a dried blood spot screening test initiated on June 15, 2020. Those participants identified as reactive were advised to have confirmatory testing via a venipuncture. Venipuncture results through August 8, 2020, were considered. Consent and authorization for testing was required to participate in the screening program. This report, which was conducted under an institutional review board-approved protocol, only includes employees who have further authorized their records for use in research. RESULTS: A total of 81,113 health care personnel were eligible for the program, and of these 29,606 participated in the screening program. A total of 4284 (14.5%) of the dried blood spot test results were "reactive" and warranted confirmatory testing. Confirmatory testing was completed on 4094 (95.6%) of the screen reactive with an overall seroprevalence rate of 0.60% (95% CI, 0.52% to 0.69%). Significant variation in seroprevalence was observed by region of the country and age group. CONCLUSION: The seroprevalence for SARS-CoV-2 antibodies through August 8, 2020, was found to be lower than previously reported in other health care organizations. There was an observation that seroprevalence may be associated with community disease burden.

The effect of operator variability and experience in vertebroplasty outcomes.

PURPOSE: To determine if operator variability, prior vertebroplasty experience, or acquired vertebroplasty experience affects clinical outcomes. MATERIALS AND METHODS: Informed consent was obtained from all patients and all data were handled in a manner consistent with institutional review board guidelines and the Health Insurance Portability and Accountability Act. Outcomes from 841 vertebroplasties, sorted by operator, were studied; two operators had previous vertebroplasty experience and five were neurointerventionalists who were initially new to the procedure. Objective (Roland-Morris Disability Questionnaire [RDQ] and analog pain scales) and subjective (mobility, narcotic use) scores were monitored before and after vertebroplasty at specified intervals following treatment. Perioperative cement volume utilization, complications, and number of treated levels were recorded. Random-effects and repeated-measures analyses of variance were used to assess operator differences and variability in clinical outcomes while generalized linear mixed-model regression analyses were used to track changes in clinical outcomes over time. RESULTS: All operators provided similar average durable clinical improvements in postoperative pain and disability with nonsignificant interoperator variability. However, generalized linear model regression suggests that four of five initially novice operators showed significant changes in several procedural measures and clinical outcomes over the study timeframe, including cement volume utilization (reduction of 3.64 to 4.63 cm(3)), 1 week RDQ score (reduction of 4.79 to 8.62 points) and postoperative rest pain (reduction of 1.18 to 2.03 points). CONCLUSION: Changes over time in measured outcomes suggest the presence of a training effect among novice operators. Cement volume utilization and immediate postprocedural pain decrease with experience but long-term clinical outcomes are insensitive to operator experience.

A unilateral vertebroplasty approach using a curved injection cannula for directed, site-specific vertebral body filling.

The present report describes the use of a curved, coaxial infusion cannula that can be applied to facilitate targeted multifocal vertebral body cement injection during vertebroplasty from a single access site. Two representative cases are presented that illustrate the ability of targeted cement deposition and flexible site selection with this technique.

The Importance of a Radiologist-Administrator Partnership to Future Health Care.

Successful physician and administrator leader partnerships are a key differentiator in today's volatile, unpredictable, ever-changing health care landscape. Whether they are leading a division, a department, or an organization, intentional and mindful physician-administrator partnerships affect success from the micro individual level to the macro organizational level. Mayo Clinic's physician and administrative leaders are leveraging a long-held tradition of partnership by elevating their own competence as effective partners to ensure organizational sustainability. Specifically, physician and administrator leaders in the department of radiology have positioned collaboration at the foundation of their leadership practice, surrounded by the institutional values of respect, excellence, stewardship, and teamwork. From this framework, team leaders are better equipped and in a more stable position to prepare themselves and their colleagues for the very complex and unknown future.

Prevalence of hyperdense paraspinal vein sign in patients with spontaneous intracranial hypotension without dural CSF leak on standard CT myelography.

PURPOSE: A recently identified and treatable cause of spontaneous intracranial hypotension (SIH) is cerebrospinal fluid (CSF)-venous fistula, and a recently described computed tomography myelogram (CTM) finding highly compatible with but not diagnostic of this entity is the hyperdense paraspinal vein sign. We aimed to retrospectively measure the prevalence of the hyperdense paraspinal vein sign on CTMs in SIH patients without dural CSF leak, in comparison with control groups. METHODS: Three CTM groups were identified: 1) SIH study group, which included dural CSF leak-negative standard CTMs performed for SIH, with early and delayed imaging; 2) Early control CTMs, which were performed for indications other than SIH, with imaging shortly after intrathecal contrast administration; 3) Delayed control CTMs, which included delayed imaging. CTMs were retrospectively reviewed for the hyperdense paraspinal vein sign by experienced neuroradiologists, blinded to the group assignment. All CTMs deemed by a single reader to be positive for the hyperdense paraspinal vein sign were independently reviewed by two additional neuroradiologists; findings were considered positive only if consensus was present among all three readers. For positive cases, noncontrast CTs and prior CTMs, if available, were reviewed for the presence of the sign. RESULTS: Seven of 101 (7%) SIH patients had contrast in a spinal/paraspinal vein consistent with the hyperdense paraspinal vein sign; no patient in either control group (total n=54) demonstrated the hyperdense paraspinal vein sign (P = 0.0463). The finding occurred only at thoracic levels. Each patient had a single level of involvement. Six (86%) occurred on the right. Four occurred in female patients (57%). The sign was seen on early images in 3 of 7 cases (43%) and on both early and delayed images in 4 of 7 cases (57%). In 2 of 7 patients (29%), a noncontrast CT covering the relevant location was available and negative for the sign. A prior CTM was available in 2 of 7 patients (29%), and in both cases the hyperdense paraspinal vein sign was also evident. CONCLUSION: The prevalence of the hyperdense paraspinal vein sign in SIH patients with dural CSF leak-negative standard CTM was 7%. As the sign was not seen in control groups, this sign is highly compatible with the presence of CSF-venous fistula. Since the CTMs were not specifically dedicated to identifying hyperdense paraspinal veins (i.e., they were not dynamic and were not preceded by digital subtraction myelography), the true prevalence of the sign may be higher. Radiologists should scrutinize conventional CTMs for this sign, especially in patients in whom a traditional dural CSF leak is not identified.

Penetrating Osseous Spicules Causing High-Flow Ventral CSF Leaks in the Setting of Relatively Low BMI : A Preliminary Study.

OBJECTIVE/BACKGROUND: We have anecdotally observed patients with high-flow ventral cerebrospinal fluid (CSF) leaks resulting from penetrating osseous spicules or calcified discs to be relatively thin. The purpose of this study was to explore the validity of this observation and determine if a potential association exists between low body mass index (BMI) and high-flow spinal ventral CSF leaks resulting from such dura-penetrating lesions. METHODS: Sixteen consecutive patients with precisely localized high-flow ventral spinal CSF leaks on dynamic myelography were identified. The cause of the CSF leak was determined. The BMI on the date nearest to and within 2 weeks of myelography was recorded. Utilizing exact sign test, the body mass index was compared to the average BMI from the National Health and Nutrition Examination Survey (Centers for Disease Control), matched to sex and age-range. RESULTS: The cohort consisted of 10 males (63%) and 6 females with a mean age of 54 years (range 37-72 years). In all patients, a spiculated osteophyte/calcified disc was identified at the site of the leak. Fourteen patients (88%) had a BMI below the matched national average, while only two patients (13%) had values above the national average (p = 0.004). CONCLUSIONS: Patients with high-flow ventral CSF leaks resulting from spiculated osteophyte or calcified disc as identified by dynamic myelography are more likely to have a BMI below the U.S. national average, matched for gender and age-range. This exploratory analysis requires confirmation as well as further characterization of potential pathophysiologic mechanisms and impact on radiographic and clinical assessments.