Successful fusion versus pseudarthrosis after spinal instrumentation: a comprehensive imaging review.

PURPOSE: Following spinal instrumentation and fusion, differentiating between successful arthrodesis and pseudoarthrosis on imaging can be challenging. Interpretation of such examinations requires understanding both the expected evolution of postoperative findings and the subtle indicators of pseudoarthrosis across multiple imaging modalities. Due to this level of intricacy, many clinicians lack familiarity with the subject beyond the more rudimentary concepts. METHODS: This review provides an in-depth overview of the imaging of the post-operative spine, with particular emphasis on differentiating between pseudoarthrosis and arthrodesis. RESULTS: A comprehensive overview of imaging of the post-operative spine is given, including the most common imaging modalities utilized, the expected post-operative findings, imaging findings in pseudoarthrosis, and imaging definitions of fusion. CONCLUSION: Differentiating between pseudoarthrosis and arthrodesis in the postoperative spine is complex, and requires a robust understanding of various findings across many different modalities.

Beyond plaque: A pictorial review of non-atherosclerotic abnormalities of extracranial carotid arteries.

The common carotid artery (CCA) and extracranial internal carotid artery are subject to a wide variety of non-atheromatous pathologies. These entities are often overshadowed in both research and clinical realms by atherosclerotic disease. Nevertheless, non-atherosclerotic disease of the carotid arteries may have profound, even devastating, neurologic consequences. Hence, this review will cover both common and uncommon forms of extracranial carotid artery pathologies in a pictorial format, in order to aid the diagnostician in identifying and differentiating such pathologies.

Synovial Cysts Confounding Access to the Dorsal S1 Neural Foramen in Transforaminal Epidural Steroid Injections.

OBJECTIVES: The S1 dorsal foramen is the route for 30% of lumbar transforaminal epidural injections; it is therefore important to identify structures impeding S1 foraminal access. The study objective was to characterize the imaging findings, prevalence, and anatomic origin of synovial cysts presenting within the S1 neural foramen. METHODS: A case series (N = 14) established imaging characteristics of S1 synovial cysts. Imaging studies of 400 patients undergoing epidural injections were reviewed for lesions compromising S1 foraminal access. Cadaveric dissections defined the relationship of the inferior recess of the L5-S1 facet to the S1 dorsal foramen. RESULTS: Elderly patients (mean age = 76) exhibited S1 synovial cysts. Synovial cysts were typically 1-2 cm in diameter, hyperintense on sagittal T2 weighted magnetic resonance images (MRIs), fluid-density on computed tomography, and dorsal to the S1 spinal nerve. Sixty percent of cysts exhibited complex MRI signal characteristics (thick wall, internal structure). Tarlov cysts, in contrast, were larger, lobular, and exhibited pure fluid intensity. Lesions impeded access to the S1 dorsal foramina in 5% of reviewed imaging studies (16 Tarlov cysts, three synovial cysts, one conjoint S1-S2 nerve root). The multifidus muscle was interposed between the L5-S1 facet inferior recess and the S1 dorsal foramen on dissection specimens; severe atrophy of the ipsilateral multifidus was noted on imaging in 17/18 synovial cysts. CONCLUSIONS: The S1 neural foramina should be inspected on sagittal MRI, when available, for confounding lesions before performing S1 epidural injections. Tarlov cysts are more common than synovial cysts; the latter are seen in elderly patients with severe multifidus atrophy.

The Impact of Social Media on Negative Online Physician Reviews: an Observational Study in a Large, Academic, Multispecialty Practice.

BACKGROUND: Online reviews of physicians are becoming increasingly common, however no correlation of these reviews to formal patient satisfaction surveys. With the explosion of social media, it is unknown as to how this form of communication may have a role in potentially managing and addressing the search position of negative online reviews. METHODS: We obtained a list of 102 physicians with negative online reviews between September 2014 and December 2014. Social media uptake and average Google search position of the physician and their respective negative online reviews were assessed from January 2015 through January 2017. RESULTS: Fifty-four (53%) physicians had any social media presence in January 2015. All 102 physicians were subsequently offered social media coaching by the Mayo Clinic Center for Social Media which resulted in an increase to 90% of these physicians participating in social media by January 2017. The average Google search position for the negative online reviews was significantly reduced from 5.2 ± 2.5 to 14.3 ± 11.3 (P < 0.001) from 2015 to 2017. There was a moderate increase in Doximity uptake during that time increasing from 11% of the physicians having a claimed profile to 80%. There were non-significant reductions in the average Google search position - 9.7 ± 11.3 in the physicians who had an existing a social media presence versus those who were not on social media - 4.2 ± 2.2 (P = 0.11). CONCLUSIONS: Physician social media presence can reduce the bearing of negative online comments by decreasing the search position of these comments.

Prevalence of Developmental Venous Anomalies Increases With Age.

BACKGROUND AND PURPOSE: To test the hypothesis that developmental venous anomalies (DVAs) may develop in the postnatal period, we studied the age-related prevalence of DVAs on contrast-enhanced magnetic resonance imaging. METHODS: Reports from a consecutive series of head magnetic resonance images with intravenous contrast performed over a 2-year period at our institution were reviewed. Studies reporting the presence of a DVA were retrieved and reviewed by a neuroradiologist. Patients were divided into 4 age groups: (1) <1 year old (neonates/infants), (2) 1 to 5 years old (toddlers and preschoolers), (3) 6 to 17 years old (grade schoolers), and (4) ≥18 years old (adults), and DVA prevalence by age group was studied. RESULTS: A total of 18 073 individuals were included. DVA prevalence in the neonate/infant age group was 1.5% (5/335) compared with 7.1% (51/714) in the toddler/preschool age group. In both the grade-school age group and adult age group, DVA prevalence was 9.6% (150/1557 and 1483/15 467, respectively). Neonates/infants were significantly less likely to have DVAs than other age groups (P<0.001). CONCLUSIONS: We found a very low prevalence of DVAs on contrast-enhanced magnetic resonance imaging in patients <1 year old which was significantly lower than other age groups. These findings suggest that postnatal changes in venous architecture and drainage patterns may contribute to the development of DVAs.

Imaging Appearance of Advanced Chronic Adhesive Arachnoiditis: A Retrospective Review.

OBJECTIVE: Chronic adhesive arachnoiditis (CAA) is rare and has potentially devastating clinical consequences. The objective of this article is to review the clinical features of CAA and describe its appearance on imaging, to increase radiologists' awareness of this challenging diagnosis. MATERIALS AND METHODS: Twenty-nine cases of advanced CAA seen at our institution over 18 years (1995-2013) were retrospectively reviewed. Chart review was performed, with attention given to data on clinical presentation, suspected cause, and interventions performed. All patients underwent MRI, and seven patients also underwent CT myelography. Clinical and imaging features were evaluated and categorized. RESULTS: The 29 patients ranged in age from 23 to 96 years and included 11 women and 18 men. Suspected underlying causative factors included trauma (n = 10), prior surgery (n = 9), nontraumatic subarachnoid hemorrhage (n = 7), infection (n = 3), myelography with iophendylate used as contrast medium (n = 1), Guillain-Barré syndrome (n = 1), ankylosing spondylitis (n = 1), and unknown causes (n = 1). Imaging characteristics include loculated CSF collections (n = 23), nerve root clumping, enhancement, and displacement (n = 15), cord swelling with increased T2 signal (n = 12), arachnoid septations (n = 11), cord atrophy (n = 6), syrinx (n = 5), and intrathecal calcifications (n = 3). Ten patients underwent surgical procedures, and most had only brief clinical improvement. CONCLUSION: CAA is a rare cause of devastating neurologic symptoms and chronic pain. The imaging features of CAA range from subtle to severe. Advanced arachnoiditis can present with spinal cord swelling and syrinx formation, which can mimic other disease processes. Inclusion of advanced CAA in the differential diagnosis can prevent unnecessary interventions.

Prevalence of cerebral cavernous malformations associated with developmental venous anomalies increases with age.

BACKGROUND AND PURPOSE: To test the hypothesis that the prevalence of cerebral cavernous malformation (CCM) associated with developmental venous anomalies (DVAs) increases with age, we studied the age-related prevalence of DVA-associated CCM among patients with DVAs. MATERIALS AND METHODS: Patients with DVAs on contrast-enhanced MRI exams performed over a 2-year period were included in this study. A single neuroradiologist reviewed all imaging exams for the presence of CCMs. Baseline demographic data collected included age, gender, presence of CNS neoplasm, history of cranial radiation, and history of seizure. Patients were divided into age groups based on decade of life. Cochran-Armitage trend tests were performed to determine if increasing age was associated with CCM prevalence. RESULTS: A total of 1689 patients with DVAs identified on contrast-enhanced MRI were included. Of these patients, 116 (6.9%) had a cavernous malformation associated with the DVA. There was a significant positive association between age and the prevalence of DVA-associated CCM (P = 0.002). The prevalence of DVA-associated CCM was 0.8% for the 0-10 age group, 1.6% for the 11-20 age group, 7.5% for the 21-30 age group, 9.5% for the 31-40 age group, 6.1% for the 41-50 age group, 6.3% for the 51-60 age group, 7.4% for the 61-70 age group, and 11.6% for the >70 age group (P < .0001). CONCLUSIONS: Our study demonstrated an age-related increase in prevalence of DVA-associated cavernous malformations among patients with DVAs. These findings suggest that DVA-associated cavernous malformations are acquired lesions.

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.

Imaging Determinants of Clinical Effectiveness of Lumbar Transforaminal Epidural Steroid Injections.

OBJECTIVE: To examine associations between imaging characteristics of compressive lesions and patient outcomes after lumbar transforaminal epidural steroid injections (TFESIs) stratified by steroid formulation (solution versus suspension). DESIGN/SUBJECTS: Retrospective observational study, academic radiology practice. A 516-patient sample was selected from 2,634 consecutive patients receiving lumbar TFESI for radicular pain. METHODS: The advanced imaging study(s) preceding sampled TFESI were reviewed. Compressive lesions were described by a) nature of the lesion [disc herniation, fixed stenosis, synovial cyst, epidural fibrosis, no lesion] b) degree of neural compression [4 part scale], and c) presence of a tandem lesion. Associations between 2-month categorical outcomes (responder rates for pain, functional recovery) and imaging characteristics, stratified by steroid formulation, were examined with chi-squared tests of categorical outcomes and multivariable logistic regression models. RESULTS: Disc herniation patients had more responders for functional recovery than patients with fixed lesions (54% versus 38%, P = 0.01). Patients with fixed lesions receiving steroid solution (dexamethasone) had more responders for pain relief, with a similar trend for functional recovery, than patients receiving suspensions (59% versus 40%, P = 0.01). Outcomes for patients with fixed lesions treated with dexamethasone were not statistically different from those for disc herniation patients. Patients with single compressive lesions had more responders than those with tandem lesions (55% versus 41%, P = 0.03). CONCLUSION: In the entire sample, outcomes for disc herniations were more favorable than for fixed lesions. However, fixed lesions treated with dexamethasone had outcomes indistinguishable from disc herniations. Single lesions had better outcomes than tandem lesions.

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 cause of atypical intracranial subarachnoid hemorrhage: posterior spinal artery aneurysms.

BACKGROUND: Approximately 1 % of cases of intracranial subarachnoid hemorrhage (SAH) are caused by spinal vascular pathologies. Among them, isolated spinal artery aneurysms are uncommon and a limited number of cases have been reported in the literature. METHODS: This is a report of two cases and review of the literature. RESULTS: Both patients presented with an atypical intracranial SAH and were also found to have spinal SAH caused by a ruptured posterior spinal aneurysm. CONCLUSION: Isolated spinal artery aneurysms represent a rare cause of intracranial SAH. Symptoms such as back pain and lower-extremity weakness can be clues to the adequate diagnosis. Surgical or endovascular treatment should be pursued in all patients, as the risk of rebleeding is non-negligible.

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.

Tumefactive cerebral amyloid angiopathy mimicking CNS neoplasm.

OBJECTIVE: The tumefactive variant of cerebral amyloid angiopathy (CAA) is rare. In this article we describe imaging findings associated with this entity and evaluate the role of susceptibility MRI sequences in its diagnosis. CONCLUSION: Our findings suggest that in elderly patients, susceptibility sequences should be part of prebiopsy MRI for tumefactive lesions. Identification of characteristic diffuse microhemorrhages should prompt inclusion of CAA in the differential diagnosis, targeted biopsy of the cortex and leptomeninges, and pathologic staining for CAA.

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 Central Dot Sign : A Specific Post-gadolinium Enhancement Feature of Intramedullary Spinal Cord Metastases.

PURPOSE: Peripheral enhancement characteristics on magnetic resonance imaging (MRI), namely the rim and flame signs, are specific for intramedullary spinal cord metastases (ISCM) compared to primary cord masses. The study compared the frequency of a novel finding-the central dot sign-in ISCMs versus primary intramedullary masses. METHODS: In this study 45 patients with 64 ISCMs and 64 control patients with 64 primary intramedullary cord masses were investigated and 2 radiologists blinded to lesion type independently evaluated MR images for the presence of a central dot sign: a punctate focus of enhancement in/near the center of an enhancing intramedullary mass. The frequency of this sign in the two patient groups was compared. RESULTS: A total of 63 enhancing ISCMs in 44 patients and 54 enhancing primary cord masses in 54 patients were included. The central dot sign was identified in 6% (4/63) of enhancing ISCMs in 9% (4/44) of patients and in none (0/54) of the enhancing primary cord masses (p = 0.038, per patient). The specificity for diagnosing ISCMs among spinal cord masses was 100%. The central dot sign was present in the axial plane only in two ISCMs and in the axial and sagittal planes in two ISCMs. The two ISCMs harboring the central dot sign also demonstrated both the previously described rim and flame signs, and two also demonstrated the rim sign alone. CONCLUSION: The central dot sign is not sensitive but highly specific for ISCMs compared to primary spinal cord masses. The rim and/or flame signs may or may not be concurrently present in ISCMs.