Lumbar Spine MRI Research Articles

Trends in Hospital Performance on the Medicare National Outpatient Imaging Metrics: A 5-Year Longitudinal Cohort Analysis

PurposeMedicare established its Hospital Outpatient Quality Reporting Program (HOQRP) to promote and incentivize quality care and appropriate utilization in the hospital outpatient setting. The program includes “imaging efficiency” metrics evaluating appropriate utilization of imaging examinations. Our purpose was to evaluate the longitudinal performance of the nation’s hospitals on the HOQPR’s imaging efficiency metrics. MethodsData were obtained from CMS Hospital Compare for hospitals participating in the Medicare HOQRP during both initial (January 1, 2011, to December 31, 2011) and follow-up (July 1, 2015, to June 30, 2016) periods. The six reported imaging efficiency metrics were: MRI lumbar spine for low back pain, mammography follow-up rates, abdomen and chest CT double scans (imaging with and without intravenous contrast), cardiac imaging for preoperative risk assessment for low-risk surgery, and simultaneous use of brain and sinus CT. Differences in imaging efficiency metrics were calculated using fixed effects linear regression models. ResultsBaseline and follow-up data were available for 3,960 hospitals. Median changes were MRI lumbar spine for low back pain: +3.6% (range: −27.9% to +31.4%; P < .001); mammography follow-up: −0.3% (range: −69.5% to +62.6%; P = .03); double scan abdomen CT: −1.9% (range: −73.5% to +32.3%; P < .001); double scan chest CT: −0.4% (range: −73.2% to +28.0%; P < .001); preoperative cardiac imaging: −0.7% (range: −10.0% to +9.9%; P < .001); simultaneous brain and sinus CT: −0.9% (range: −11.8% to +7.8%; P < .001). ConclusionMedicare’s nationwide hospital outpatient imaging efficiency reporting initiative was associating with worse performance in lumbar spine MRI utilization and small improvements in double CT scans. Because quality metrics are increasingly imposed on health care providers, health service researchers will need to rigorously evaluate their effectiveness before and during early implementation.

Inflammatory biomarkers do not distinguish between patients with sciatica and referred leg pain within a primary care population: results from a nested study within the ATLAS cohort

BackgroundThere is increasing interest in the role of pro-inflammatory cytokines in the pathogenesis of sciatica and whether these could be potential targets for treatment. We sought to investigate serum biomarker levels in patients with low back-related leg pain, including sciatica.MethodsPrimary care consulters aged > 18 with low back-related leg pain were recruited to a cohort study (ATLAS). Participants underwent a standardised clinical assessment, lumbar spine MRI and a subsample (n = 119) had samples taken for biomarker analysis. Participants were classified having: a) clinically confirmed sciatica or referred leg pain, and then subdivided into those with (or without) MRI confirmed nerve root compression due to disc prolapse. Seventeen key cytokines, chemokines and matrix metalloproteinases (MMPs) implicated in sciatica pathogenesis including TNFα and IL-6, were assayed in duplicate using commercial multiplex detection kits and measured using a Luminex suspension array system. Median biomarker levels were compared between the groups using a Mann Whitney U test. Multivariate logistic regression analysis was used to investigate the association between clinical measures and biomarker levels adjusted for possible confounders such as age, sex, and symptom duration.ResultsNo difference was found in the serum level of any of the 17 biomarkers tested in patients with (n = 93) or without (n = 26) clinically confirmed sciatica, nor between those with (n = 44) or without (n = 49) sciatica and MRI confirmed nerve root compression.ConclusionIn this cohort, no significant differences in serum levels of TNFα, IL-6 or any other biomarkers were seen between patients with sciatica and those with back pain with referred leg pain. These results suggest that in patients with low back-related leg pain, serum markers associated with inflammation do not discriminate between patients with or without clinically confirmed sciatica or between those with or without evidence of nerve root compression on MRI.

Lumbar Spine MRI: Missed Opportunities for Abdominal Aortic Aneurysm Detection

The US Preventive Services Task Force (USPSTF) recommends 1-time sonographic screening for abdominal aortic aneurysms (AAAs) in male smokers ages 65-75 and other selected individuals in this age group based on risk factors. Patients in this age range are frequent utilizers of lumbar spine MRI, in which the abdominal aorta is typically fully imaged. The purpose of this study was to assess the potential detection rate of AAAs on lumbar spine MRI performed in the USPSTF screening age range with systematic aortic measurement and the frequency with which AAAs are currently reported in practice. All consecutive lumbar spine MRI exams performed without contrast at a single academic tertiary care center over a 1-year period (4/1/2016-3/31/2017) in patients ages 65-75 were retrospectively reviewed. Maximal anteroposterior, and transverse dimensions of the abdominal aorta were measured using axial T2-weighted images, supplemented with sagittal T2-weighted images if assessment was limited by field-of-view or artifact. The detection rate of AAA, defined as dilation of the aorta to a diameter of ≥3 cm, size of AAAs detected, and frequency with which AAAs were reported, were assessed. Differences in aortic diameters and aneurysm detection rates between genders were compared with the unpaired 2-sample t test. Three hundred and ninety-five lumbar spine MRIs were reviewed, 240 (60.8%) in women and 155 (39.2%) in men, with mean ± standard deviation (SD) age of 70.2 ± 3.2 years. AAAs were detected in 38/395 (9.6%) cases, most (33/38, 86.8%) of which were <4 cm. Of these, only 4 (10.5%) were reported by the interpreting radiologist; 3/4 (75%) corresponded to aneurysms ≥4 cm. Lumbar spine MRI performed in the USPSTF AAA screening age range, especially in men, facilitates frequent detection of AAA when the aorta is systematically measured. However, in typical lumbar spine assessment, AAAs are often underreported, particularly for smaller aneurysms.

Intra- and Intersubspecialty Variability in Lumbar Spine MRI Interpretation: A Multireader Study Comparing Musculoskeletal Radiologists and Neuroradiologists

Background and PurposeThe purpose of this study is to assess the differences in degenerative spine MRI reporting between subspecialty-trained attending neuroradiologists and musculoskeletal radiologists (MSK) at a single institution, academic medical center. Materials and MethodsFifty consecutive outpatient noncontrast lumbar spine examinations were selected from the Picture Archiving and Communication System. Three MSK and 3 neuroradiologists (NR) independently reviewed and interpreted the exams at the L4-L5 and L5-S1 levels in the same manner as in clinical practice. The assessment of neural foraminal stenosis (NFS) and spinal canal stenosis (SCS) was converted to a 5-point ordinal scale. The assessment of lateral recess stenosis (LRS) and facet osteoarthritis (FO) was recorded as present/absent. Intersubspecialty and intrasubspecialty analysis was performed using Cohen's kappa coefficient with a binary matrix of all reader pairs. ResultsThere was moderate intersubspecialty agreement (k = 0.527) for NFS and SCS (k = 0.540). Intersubspecialty agreement was slight for LRS (k = 0.0818) and FO (k = 0.176). The MSK group demonstrated greater intrasubspecialty agreement in assessment of NFS and SCS compared to the NR group, with nonoverlapping confidence intervals. The NR group demonstrated greater nominal intrasubspecialty agreement in the assessment of both LRS and FO, although with nonoverlapping confidence intervals. ConclusionThere is moderate intersubspecialty agreement between MSK radiologists and neuroradiologists in reporting the severity of NFS and SCS, although MSK radiologists demonstrated greater intrasubspecialty agreement. There is slight intersubspecialty agreement for LRS and FO. The demonstration of differences in inter-reader agreement is a crucial first step to attempt to ameliorate these variabilities.

SUN-LB098 Mimic Presentation of Neuromuscular Symptoms in Thyrotoxic Periodic Paralysis in Hispanic Male

Introduction: Thyrotoxic periodic paralysis (TPP) is a rare condition characterized by sudden paralysis with profound hypokalemia. Clinical Case: A 34 year-old obese Hispanic male presented to ED with sudden onset of generalized weakness and numbness of bilateral upper & lower extremities for one day. The patient was not able to get up when he woke up in the morning. He described having blurry vision, more severe on the right side, which was associated with right retroocular pain. He reported over twenty pounds of weight loss within past two months, accompanied with intermittent episodes of watery diarrhea, palpitations, restlessness, mild headache, and dizziness. He denied loss of consciousness, urinary or fecal incontinence, fever, cough or recent respiratory infection. Past medical history included gastritis. He reported no recent trauma, injury or hospitalization. No smoking, alcohol abuse or illicit drug use. On physical examination, the patient was having mild respiratory distress. Right eye exophthalmos and normal cardiopulmonary examination were noted. Neck examination showed no thyroid gland enlargement. Neurological findings revealed cranial nerve and sensory examination intact, but all four limbs were flaccid and motor strength of all extremities was 1/5. Deep tendon reflex was absent. Initial blood test on admission showed Potassium 1.9 mmol/l, Phosphorus 2 mg/dl, Magnesium 1.9 mg/dl, Lactic acid 4.6 mmol/l, TSH 0.005 mIU/l, Free T3: 8.80 pg/ml, Free T4: 2.3 ng/ml, and TBG 14.1 mcg/dl. Thyroid peroxidase was positive. EKG revealed sinus tachycardia. ABG indicated primary respiratory acidosis. Lumbar puncture was normal and ruled out Guillain-Barré syndrome and, viral or bacterial meningitis. Thyroid sonogram showed heterogeneous thyroid with no nodules. CT head without contrast showed no evidence of intracranial hemorrhage. MRI brain revealed no intracranial mass. MRI lumbar & thoracic spine showed a normal finding. After the aggressive replacement of potassium chloride, the muscle weakness improved significantly, and methimazole was initiated. The patient was admitted to ICU for close monitoring and electrolyte management. Conclusion: Thyrotoxicosis periodic paralysis (TPP) is a rare condition that manifests through acute paralysis, and hypokalemia in the presence of hyperthyroidism (1). It is usually found in relatively young Asian population, but also the occurrence has increased in the Hispanic population recently. Early recognition of TPP in a patient with unexplained hypokalemia and painless generalized weakness, is imperative to demand thyroid studies to rule out this condition. Close electrolyte management is important rebound hyperkalemia and life-threatening arrhythmias. Reference: (1) Meseeha M et al. Thyrotoxic periodic paralysis: a case study and review of the literature. J Community Hosp Intern Med Perspect. 2017;7(2):103-106. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. s presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.

Proton density fat fraction MRI of vertebral bone marrow: Accuracy, repeatability, and reproducibility among readers, field strengths, and imaging platforms.

Chemical shift-encoding based water-fat MRI is an emerging method to noninvasively assess proton density fat fraction (PDFF), a promising quantitative imaging biomarker for estimating tissue fat concentration. However, in vivo validation of PDFF is still lacking for bone marrow applications. To determine the accuracy and precision of MRI-determined vertebral bone marrow PDFF among different readers and across different field strengths and imager manufacturers. Repeatability/reproducibility. Twenty-four adult volunteers underwent lumbar spine MRI with one 1.5T and two different 3.0T MR scanners from two vendors on the same day. 1.5T and 3.0T/3D spoiled-gradient echo multipoint Dixon sequences. Two independent readers measured intravertebral PDFF for the three most central slices of the L1-5 vertebral bodies. Single-voxel MR spectroscopy (MRS)-determined PDFF served as the reference standard for PDFF estimation. Accuracy and bias were assessed by Pearson correlation, linear regression analysis, and Bland-Altman plots. Repeatability and reproducibility were evaluated by Wilcoxon signed rank test, Friedman test, and coefficients of variation. Intraclass correlation coefficients were used to validate intra- and interreader as well as intraimager agreements. MRI-based PDFF estimates of lumbar bone marrow were highly correlated (r2 = 0.899) and accurate (mean bias, -0.6%) against the MRS-determined PDFF reference standard. PDFF showed high linearity (r2 = 0.972-0.978) and small mean bias (0.6-1.5%) with 95% limits of agreement within ±3.4% across field strengths, imaging platforms, and readers. Repeatability and reproducibility of PDFF were high, with the mean overall coefficient of variation being 0.86% and 2.77%, respectively. The overall intraclass correlation coefficient was 0.986 as a measure for an excellent interreader agreement. MRI-based quantification of vertebral bone marrow PDFF is highly accurate, repeatable, and reproducible among readers, field strengths, and MRI platforms, indicating its robustness as a quantitative imaging biomarker for multicentric studies. 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1762-1772.

Sociodemographic Variation in the Use of Conservative Therapy Before MRI of the Lumbar Spine for Low Back Pain in the Era of Public Reporting

PurposeTo evaluate the relationship between use of MRI of the lumbar spine for low back pain without prior conservative therapy and sociodemographic factors after the implementation of public reporting for Medicare's Hospital Outpatient Imaging Efficiency Measure for MRI Lumbar Spine for Low Back Pain (OP-8) metric. Materials and MethodsWe conducted a secondary data analysis using a nationally representative sample of 2009 to 2014 Medicare claims to evaluate trends in use of conservative therapy before MRI of the lumbar spine. Continuously enrolled fee-for-service Medicare beneficiaries were included. We applied the same criteria used by Medicare to generate a measure consistent with OP-8. Regression was used to evaluate trends in OP-8 by reporting status (outpatient hospital or clinic) and beneficiary characteristics. Age, sex, and race from the Medicare denominator and area-level socioeconomic measures from the Area Health Resource File were used as covariates. ResultsUse of conservative therapy before MRI increased regardless of OP-8 reporting status. Several sociodemographic characteristics were associated with the likelihood of receiving conservative therapy before MRI; beneficiaries were less likely to receive conservative therapy before MRI if they were male, older, black, Hispanic or Latino; if they lived in the West or in an area with more college graduates; or if they had low incomes. Beneficiaries were more likely to receive conservative therapy before MRI if they had poorer health or lived in areas with higher home values. ConclusionVariations in use of conservative therapy according to factors other than clinically relevant factors, such as health status, are worrying. Further strategies are needed to improve appropriateness and equity in the provision of diagnostic imaging.

Preoperative assessment of idiopathic scoliosis in adolescent and young adult with three-dimensional T2-weighted spin-echo MRI.

To compare tridimensional (3D) T2-weighted spin-echo MRI and CT for minimal pedicle width measurements in the preoperative assessment of adolescent idiopathic scoliosis (AIS) in adolescent and young patients. A total of 22 adolescents/young patients suffering from AIS were retrospectively included. There were 18 females and 4 males with a mean age of 15.3±2.3 (SD) years (range: 11-21years). Preoperative lumbar spine MRI and CT examinations of the 22 patients were reviewed by two independent readers who measured the minimal width of 259 pedicles. Inter-reader agreement for CT and MRI was assessed using intra-class correlation coefficient (ICC). Intra-reader agreement and relative differences in measurements between MRI and CT were also assessed for each reader. Inter-reader agreement was excellent (ICC≥0.8) for both CT and MRI. Relative differences in measurements between CT and MRI was 10.3% for reader 1 and 9.4% for reader 2. 3D T2-weighted spin-echo MRI underestimates minimal pedicle width by only 9.4 - 10.3% compared to CT. 3D T2-weighted MRI appears as a valuable alternative to CT for preoperative measurements of vertebral pedicles in AIS.

Volumetric evaluation of lumbar epidural fat distribution in epidural lipomatosis and back pain in patients who are obese: introducing a novel technique (Fat Finder algorithm)

ObjectiveSpinal epidural lipomatosis (EL) represents an excessive deposition of unencapsulated adipose tissue in the spinal canal that can result in chronic back pain in patients who are obese with and...

Association of chronic degenerative arthritis related chronic low back pain with altered lumbar facet joint orientation

ObjectiveTo examine the relationship between changes in lumbar spine facet joint (FJ) orientation and chronic low back pain (CLBP). MethodsWe retrospectively analyzed lumbar spine CT and MRI images of 98 patients referred for localized paraspinal CLBP and 98 age-and sex-matched asymptomatic individuals as controls. They were divided into four age groups (A, <40; B, 41–50; C, 51–60; D, 61–70; and E, 71–80 years old, respectively). FJ orientations were evaluated at the L3-4, L4-5, and L5-S1 lumbar levels. ResultsFJ angle showed a statistically significant more sagittal orientation in CLBP patients than in control groups in lower lumbar spine segments. The overall mean FJ angles in CLBP groups including all age groups combined at L3-4, L4-5, and L5-S1 levels were 32.33 ± 4.5, 36.11 ± 2.9, and 37.4 ± 6.1, degrees, respectively. The FJ angles in control group for all ages were 32.21 ± 3.7, 38.01 ± 4.6, and 40.18 ± 6.8°, respectively. The differences in FJ angle were statistically significant at both L4-5 and L5-S1 levels between the control and the CLBP groups (p < 0.01). The FJ orientation from upper lumbar spine to lumbar sacral junction demonstrated a gradual more coronal orientation transition in all subjects but this trend was significantly less in CLBP patients. The mean FJ angles for the control group at age groups A, B, C, D, and E were 33.52 ± 3.8, 35.7 ± 4.5, 38.25 ± 2.4, 35.49 ± 4.1, and 38.13 ± 5.8, respectively, while those in the CLBP groups were 35.63 ± 2.4, 35.26 ± 3.6, 35.99 ± 5.1, 35.3 ± 4.3, and 35.17 ± 6.7, respectively. ConclusionThere is a significant association between a more sagittal FJ orientation and facetogenic CLBP in lower lumbar vertebral levels. There is also age-dependent decrease in FJ orientation in sagittal plane at lower lumbar spinal levels in control as well as CLBP groups, however, this decrease in the CLBP groups was significantly more pronounced. Whether this change was an adaptive remodeling or alterations associated with chronic FJ osteoarthropathy should warrant further longitudinal studies.

Magnitude and financial implications of inappropriate diagnostic imaging for three common clinical conditions.

To quantify the level of adherence to imaging guidelines for three common clinical indications for a commercially insured population. Retrospective analysis of administrative claims data for commercially insured individuals with diagnostic imaging claims (MRI and X-ray) for either uncomplicated low back pain, non-traumatic knee pain or non-traumatic shoulder pain. The State of Massachusetts for 2010 and 2013. Adults with no chronic conditions and without evidence of prior management in the 12 months preceding to the initial office visit for each of the clinical indications. Imaging procedures performed within 30 days of the initial office visit were classified as appropriate or inappropriate according to adherence to imaging guidelines from American College of Radiology. More than 60% of lumbar spine MRI's were deemed inappropriate in 2010 and in 2013. Over 30% of MRI's for shoulder pain and knee pain were inappropriate in 2010 and in 2013. Patients age 18-59 with inappropriate imaging claims had significantly lower rates of surgical procedures within 90 days of imaging than those with appropriate imaging. Inappropriate imaging accounted for over 20% of annual imaging costs for the three clinical indications. Reducing inappropriate imaging procedures can lead to substantial savings through the elimination of unnecessary and low value procedures. Increased awareness of and adherence to best practice guidelines should be a focus of efforts to cut waste in our healthcare system.

Readability of Lumbar Spine MRI Reports: Will Patients Understand?

Radiology reports have traditionally been written for referring clinical providers. However, as patients increasingly access their radiology reports through online medical records, concerns have been raised about their ability to comprehend these complex documents. The purpose of this study was to assess the readability of lumbar spine MRI reports. We reviewed 110 lumbar spine MRI reports dictated by 11 fellowship-trained radiologists (eight musculoskeletal radiologists and three neuroradiologists) at a single academic medical center. We evaluated each article for readability using five quantitative readability tests: the Flesch-Kincaid Grade Level, Flesch Reading Ease, Gunning Fog Index, Coleman-Liau Index, and the Simple Measure of Gobbledygook. The number of reports with readability at or below eighth-grade level (average reading ability of U.S. adults) and at or below sixth-grade level (level recommended by the National Institutes of Health and the American Medical Association for patient education materials) were determined. The mean readability grade level of the lumbar spine MRI reports was greater than the 12th-grade reading level for all readability scales. Only one report was written at or below eighth-grade level; no reports were written at or below sixth-grade level. Lumbar spine MRI reports are written at a level too high for the average patient to comprehend. As patients increasingly read their radiology reports through online portals, consideration should be made of patients' ability to read and comprehend these complex medical documents.

Evaluation of diagnostic value and T2-weighted three-dimensional isotropic turbo spin-echo (3D-SPACE) image quality in comparison with T2-weighted two-dimensional turbo spin-echo (2D-TSE) sequences in lumbar spine MR imaging

Purposeto evaluate diagnostic value and image quality of T2-weighted Three-dimensional isotropic turbo spin-echo (SPACE) in comparison with T2-weighted two-dimensional turbo spin-echo (TSE) sequences for comprehensive evaluation of lumbar spine pathologies. Materials and methodsThirty-five participants with lumbar discopathy were examined on a 1.5-T MRI system with both 2D TSE and 3D SPACE sequences. Obtained images were analyzed with synedra view personal (V 17.0.0.2) software in terms of calculating image quality factors such as signal to noise ratio (SNR) and contrast to noise ratio (CNR) for selected regions of interest. In addition, images were referred to radiologists to report their pathologic indexes. The visibility of anatomical structures in the 3D and 2D sequences was qualitatively assessed by two radiologists independently. Cohen's kappa (k) and Wilcoxon signed rank test was used for the statistical analysis. ResultsIn this study, the 3D SPACE T2-weighted sequence showed significant higher SNR and CNR as well as visibility in all of the regions of interest except vertebrae and intervertebral discs (p-value < 0.05). Inter-observer agreement for visibility of regions of interest was substantial and perfect (k > 0.6). Also, inter-observer and inter-method agreements for pathologic indexes were substantial and perfect for all of the pathologic indexes (k > 0.6). Inter-observer agreement for 3D SPACE sequence was higher (k = 0.793) in comparison with 2D-TSE sequence (k = 0.603). 3D SPACE sequence and its multi-planar reconstructions (MPR) scan time were less (192 s) than 2D TSE in the sagittal, axial and coronal planes (209 s). Conclusion3D SPACE sequence for lumbar spine MRI proved to have higher SNR, CNR, and visibility for all regions of lumbar spine except vertebrae and disc. Inter-observer and inter-method agreements for pathologic indexes between 3D SPACE and 2D TSE sequences were substantial and 3D SPACE had a higher inter-observer agreement and less scan time. Therefore, T2 weighted 3D SPACE sequence, and its MPR might be an excellent alternative for 2D TSE in sagittal, axial, and coronal planes, especially for patients with abnormal curvature of the lumbar spine.

Integrity of clinical information in computerized order requisitions for diagnostic imaging.

Assess information integrity (concordance and completeness of documented exam indications from the electronic health record [EHR] imaging order requisition, compared to EHR provider notes), and assess potential impact of indication inaccuracies on exam planning and interpretation. This retrospective study, approved by the Institutional Review Board, was conducted at a tertiary academic medical center. There were 139 MRI lumbar spine (LS-MRI) and 176 CT abdomen/pelvis orders performed 4/1/2016-5/31/2016 randomly selected and reviewed by 4 radiologists for concordance and completeness of relevant exam indications in order requisitions compared to provider notes, and potential impact of indication inaccuracies on exam planning and interpretation. Forty each LS-MRI and CT abdomen/pelvis were re-reviewed to assess kappa agreement. Requisition indications were more likely to be incomplete (256/315, 81%) than discordant (133/315, 42%) compared to provider notes (p < 0.0001). Potential impact of discrepancy between clinical information in requisitions and provider notes was higher for radiologist's interpretation than for exam planning (135/315, 43%, vs 25/315, 8%, p < 0.0001). Agreement among radiologists for concordance, completeness, and potential impact was moderate to strong (Kappa 0.66-0.89). Indications in EHR order requisitions are frequently incomplete or discordant compared to physician notes, potentially impacting imaging exam planning, interpretation and accurate diagnosis. Such inaccuracies could also diminish the relevance of clinical decision support alerts if based on information in order requisitions. Improved availability of relevant documented clinical information within EHR imaging requisition is necessary for optimal exam planning and interpretation.

Incidental Renal Lesions on Lumbar Spine MRI: Who Needs Follow-Up?

Incidentally discovered renal lesions on lumbar spine MRI are a common occurrence. Many follow-up recommendations are generated by radiologists encountering renal lesions to help characterize the finding as a benign cyst or a more complex, potentially malignant lesion. We hypothesized that analysis of T2-weighted imaging features of incidentally discovered renal lesions could reliably distinguish complex renal lesions from simple cysts. Two independent readers retrospectively evaluated 149 renal lesions identified on lumbar spine MRI examinations. Presence or absence of a complex renal lesion was determined using T2-weighted imaging only. Using dedicated renal cross-sectional imaging examinations as the reference standard, statistical analysis was performed to determine the accuracy of lumbar spine MRI in predicting a complex and potentially neoplastic renal lesion. Of 149 renal lesions, 115 were simple cysts, and 34 were complex renal lesions (20 Bosniak II cysts, nine renal cell carcinomas, three Bosniak IIF cysts, and two angiomyolipomas). Lumbar spine MRI readers identified 72 lesions as simple cysts and 77 lesions as complex renal lesions. Reader sensitivity for detection of a complex renal lesion on lumbar spine MRI was 94% (95% CI, 80-99%); specificity, 63% (95% CI, 53-72%); positive predictive value, 43% (95% CI, 37-49%); and negative predictive value, 97% (95% CI, 90-99%). Readers correctly identified all neoplastic and potentially neoplastic lesions (≥ Bosniak IIF). Interreader agreement was excellent (κ = 0.84). Follow-up imaging may not be required in all cases of incidentally discovered renal lesions on lumbar spine MRI. Analysis of T2-weighted imaging alone appears to reliably rule out neoplastic and potentially neoplastic complex renal lesions.

Revisiting Radiographic L5-S1 Parallelism Using MRI T1 Mapping.

Purpose:Thirty years ago, we reported that parallel aspect of the L5-S1 disc on a lateral view of the spine might be considered to be an initial stage of disk degeneration. The current study represents an attempt to increase the validity of parallel sign on conventional radiograph using MR real T1 mapping.Methods:Forty-four young asymptomatic volunteers (mean age 21.6 ± 2.3) underwent lumbar spine MRI, twice the same day, morning and afternoon. Dedicated sequences using the inversion-recovery technique were used to calculate the T1 relaxation time. A region of interest (ROI) representing the nucleus pulposus was defined in each disk. The volunteers were stratified according to the presence or absence of a parallel morphology of L5-S1. Correlation between endplates angles, sacral slopes and T1 values were then evaluated.Results:L5-S1 space looks parallel for angles <10° (mean value 6.9° ± 1.4°). Sacral slope was lower in parallel disks (31.7 ± 4.9° vs. 40.1 ± 5.6°), showing a significant difference of 8.4° (p < 0.05). The T1 relaxation values show a significant difference between the two groups (p < 0.05) with a difference of 96 ms for the morning (1090.9 ± 33.3 ms for the parallel group and 1186.9 ± 41.2 ms for the non-parallel) and 121.9 ms for the afternoon (respectively 1004.7 ± 22.2 ms and 1126.6 ± 12.9 ms).Conclusion:The difference between the two groups suggests that parallel morphology of the L5-S1 disk is associated with lower water content.

Superior articular process cross-sectional area is a new sensitive parameter for the diagnosis of lumbar central canal spinal stenosis.

PurposePrevious studies reported that hypertrophied superior articular process (SAP) was associated with an increased risk of lumbar foraminal stenosis. However, no study investigated the effect of SAP hypertrophy in lumbar central canal spinal stenosis (LCCSS). We hypothesized that the SAP cross-sectional area (SAPCSA) is the main morphologic feature in the diagnosis of LCCSS.Patients and methodsData regarding the SAPCSA were collected from 109 patients with LCCSS. All patients were enrolled after the LCCSS diagnosis was confirmed by an experienced, board-certified neuroradiologist. All patients had clinical manifestations compatible with LCCSS. A total of 120 subjects in the control group underwent lumbar spine MRI as part of non-symptomatic medical examination. T2-weighted axial images were obtained from the 2 groups. Using a picture archiving and communications system, we analyzed the CSA of the bone margin of SAP at the level of L4–L5 facet joint on MRI.ResultsThe average SAPCSA was 96.63±13.37 mm2 in the control group, and 123.59±14.18 mm2 in the LCCSS. The LCCSS group showed significantly higher levels of the SAPCSA (P<0.001) compared with the control one. Receiver operator characteristic (ROC) curve analysis was performed to determine the validity of the SAPCSA as a predictor of LCCSS. In the LCCSS group, the optimal cut-off-point was 110.71 mm2, with 83.5% sensitivity, 83.3% specificity, and area under the curve of 0.92 (95% CI: 0.88–0.95).ConclusionHigher SAPCSA values were associated with a higher possibility of LCCSS. These results are important in the evaluation of patients with LCCSS.

Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters: P45. The prevalence of incidental and symptomatic lumbar synovial facet cysts

BACKGROUND CONTEXT The prevalence of symptomatic and asymptomatic synovial facet cysts in the lumbar spine has been incompletely established, and although many studies demonstrate an association with degenerative spine disease, no cumulative increase in prevalence of synovial facet cysts with increasing age has been presented. PURPOSE To assess the prevalence of incidental (ie, asymptomatic) and symptomatic lumbar synovial facet cysts on MRI. Secondarily, we will assess if the prevalence of lumbar synovial facet cysts increases with age and what other factors are associated with its prevalence. In addition, we will assess differences in patient and cyst characteristics between asymptomatic and symptomatic facet cysts. STUDY DESIGN/SETTING Retrospective cohort study from two affiliated tertiary care referral centers for spine disease. PATIENT SAMPLE A total of 19,010 consecutive patients who underwent a dedicated lumbar spine MRI between 2004 and 2015. OUTCOME MEASURES Symptomatic and asymptomatic facet cysts. METHODS A symptomatic cyst was defined as a cyst with symptoms of radiculopathy on the same side as the cyst. The prevalence of incidental, symptomatic, and overall synovial facet cysts was reported as a percentage with 95% confidence interval (95% CI). Multivariable logistic regression analysis was used to assess if age, sex, race, and indication for MRI were associated with having a facet cyst. Generalized estimating equation analysis was used to assess differences between symptomatic versus asymptomatic synovial facet cyst: age, sex, race, side, level, cyst size, and cyst location. RESULTS The overall synovial facet cyst prevalence was 6.5% (95% CI: 6.1–6.8) [1,228/19,010]. These 1,228 patients had 1,553 synovial facet cysts of which 46% cysts (721/1,553) were incidental and 54% cysts (832/1,553) were symptomatic. The prevalence of having one or more incidental synovial facet cysts was 2.7% (95% CI: 2.5%–3.0%) [518/19,010], the prevalence of having one or more symptomatic synovial facet cysts was 3.2% (95% CI: 3.0%–3.5%) [617/19,010], and the prevalence of having both one or more incidental and one or more symptomatic synovial facet cysts was 0.49% (95% CI: 0.39%–0.59%) [93/19,010]. Increased age was independently associated with a higher likelihood of having a synovial facet cyst (odds ratio [per 10years increase in age]: 1.24, 95%CI: 1.20–1.29, p CONCLUSIONS Approximately 1 in 15 patients has at least one synovial facet cyst and about half of them are symptomatic and half are asymptomatic. Having a facet cyst — symptomatic and asymptomatic — is strongly associated with increased age supporting the theory that degenerative spine disease underlies development of facet cysts. Large cyst size and anterior location of the cysts are associated with an increased likelihood of having neurological symptoms.

Lumbar spine MRI versus non-lumbar imaging modalities in the diagnosis of sacral insufficiency fracture: a retrospective observational study

BackgroundSacral insufficiency fractures (SIFs) are a common cause of lower back pain in the elderly. However, because clinical symptoms are frequently vague and nonspecific and can mimic lumbar spine pathologies, initial imaging in SIF patients is frequently targeted at the lumbar spine rather than the sacrum, resulting in delayed diagnosis. The purpose of this study is to show the proportions of modalities used in diagnosing SIF in practice and to compare the clinical and imaging features of SIF diagnosed by lumbar spine MRI (L-spine MRI) with those diagnosed by non-lumbar imaging modalities (bone scan, pelvic bone CT, pelvis MRI).MethodsForty-two patients with SIF were enrolled in this study. SIFs diagnosed by L-spine were assigned to group 1 and SIFs diagnosed by non-lumbar imaging modalities (bone scan, pelvic bone CT, pelvis MRI) were assigned to group 2. The clinical and imaging features of SIFs were assessed and compared between two groups.ResultsSIF were more commonly diagnosed by L-spine MRI (group 1: n = 27, 64.3%) than non-lumbar imaging modalities (group 2: n = 15, 35.7%), which was comprised of pelvic bone CT (n = 6, 14.3%), bone scan (n = 5, 11.9%), and pelvis MRI (n = 4, 9.5%). Lower back pain, radiating pain and comorbid other causes of pain were more frequently identified in group 1. Fracture involving bilateral sacral ala with horizontal component was the most common shape and S2 being the most commonly involved horizontal component, without significant difference between two groups.ConclusionSIFs are more commonly diagnosed by L-spine MRI than non-lumbar imaging modalities, because of symptoms that mimic lumbar spine pathology and variable comorbid causes of pain. To know that L-spine MRI commonly reveal SIF and to be familiar with SIF features on L-spine MRI would help increase sensitivity in detecting this commonly underrecognized entity and achieve earlier and more appropriate management.

Filum terminale paraganglioma with associated cyst: a case report

Abstract Background and importance: Paragangliomas are neuroendocrine tumors that occur most often within the adrenal glands. The most frequent extra-adrenal locations include the carotid body and the jugular bulb. Filum terminale paragangliomas are extremely rare, with just 33 cases reported to date. Imagistic appearance is similar with other types of intradural extramedullary tumors such as ependymomas and schwannomas. Histopathological examination is the only method of establishing a definitive diagnosis. They are classified as grade I WHO tumors with favorable prognosis in the case of total resection. Clinical presentation: A 46-year-old woman without any relevant medical history was admitted to our Neurosurgical Department, complaining of low back pain with bilateral sciatica. She presented no neurological deficits and routine blood tests, as well as heart rate and blood pressure, were within normal ranges. Lumbar spine MRI with gadolinium enhancement revealed an intradural tumor with irregular, well defined margins and intense homogeneous enhancement, located at the level of the L3 vertebra. It presented an unenhancing intradural cystic lesion that extended cranially up to the level of the L1 vertebra. The tumor and associated cyst were completely resected through L2-L4 laminectomy. The tumor-cyst complex was attached, yet nonadherent to the conus medullaris and nerve roots, which allowed safe total removal. Histopathological examination was suggestive for paraganglioma, a diagnosis confirmed by immunohistochemistry that classified it as moderately differentiated, non-secreting type. Serum metanephrines subsequently determined were within normal ranges. Also, additional imagistic tests consisting of cervical and abdominal ultrasound and contrast enhanced CT scans did not detect any additional tumors. Postoperatively, the patient was neurologically intact, with complete remission of presenting symptoms at 3 months follow-up. Conclusion: Filum terminale paraganglioma is a rare diagnosis which is frequently overlooked. However, gross total resection, a common goal for all spinal tumors, can be curative in these particular cases.