Magnetic Resonance Imaging Of Lumbar Spine Research Articles

MRI and Anatomical Determinants Affecting Neuroforaminal Stenosis Evaluation: A Descriptive Observational Study.

PurposeNeuroforaminal stenosis (NFS), a narrowing of the intervertebral foramen, is a cause of disability in the aging population. Formal magnetic resonance imaging (MRI) classification of NSF has been developed recently and contradictory findings have been reported. This study aims to assess whether in-plane, anatomically conformed two-dimensional (2D) views of the neuroforamen characterize NFS more accurately than traditional axial, coronal, and sagittal views in healthy individuals with and without simulated scoliosis.Patients and methodsThis observational study was approved by the designated institutional review board at our academic tertiary care center. Four volunteers underwent lumbar spine MRI twice, once in the supine position and once with intentionally introduced hip tilt. The latter resulted in lumbar curvature mimicking positioning errors approximating degenerative lumbar scoliosis. Anatomically oriented cuts such as axial with endplate correction and coronally obliqued parasagittals, also called coronal obliques, were performed. Standard sagittal and axial views were also performed in both the supine and rotated groups.ResultsCoronal oblique and anatomically oriented axial views demonstrated the highest correlation with true neuroforaminal caliber. Deviation from anatomical congruence resulted in false measurements of neuroforaminal size. The hip-tilt studies produced MR that were less favorable to characterization of the caliber of neuroforamina. Coronal sections demonstrated reliability only when performed at the mid-pedicular lines. Standard axial views were reliable only when taken at the upper one-third of the neuroforamen. Coronal oblique views demonstrated superiority when evaluating consecutive neuroforamen on one image compared to non-obliqued parasagittal slices.ConclusionTo minimize error in neuroforaminal analysis, imaging specialists should perform anatomically oriented cuts to conform to individual patient anatomy. When this cannot be performed due to a patient’s spine rotation or position, the MRI reader should view oblique, axial, and coronal images simultaneously and dynamically for proper foraminal characterization.

Determination of a neurologic safe zone for bicortical S1 pedicle screw placement

BACKGROUND CONTEXTLumbosacral fixation is commonly used for the management of lumbosacral instability. As the sacrum mainly consists of cancellous bone, bicortical fixation, in which the pedicle screw penetrates the anterior sacral cortex, can help increase the strength of fixation. However, this method carries a risk to the L5 nerves which lie anterior to the sacrum at this level. PURPOSEThe goal of this study is to determine a safe zone for the placement of S1 pedicle screws to decrease the likelihood of L5 nerve injury. STUDY DESIGNRetrospective imaging review. PATIENT SAMPLEThis study evaluated imaging data of patients who underwent lumbar spine magnetic resonance imaging (MRI) at our institute between September 1, 2020 and September 1, 2021. OUTCOME MEASUREST1-weighted axial MRIs were measured at the level of S1 pedicle screw placement. The space medial and lateral to the L5 nerve root on the anterior sacrum were measured and defined as safe zones. Additionally, the nerve width and sacral lengths were measured at this level. METHODSThe distribution of the measurements were evaluated to determine a medial and lateral safe zone, as well as the average nerve width at the level of S1 pedicle screw placement. Correlation analysis was performed to determine a relationship between safe zone sizes and sacral size. RESULTSA total of 400 MRIs were analyzed. The average medial safe zone measured was 32.8 mm (95% CI: 32.2–33.4) with no nerves lying within 22.3 mm of the midline sacrum. The average lateral safe zone measured was 17.7 mm (95% CI: 17.1–18.2), with no nerves within 5.3 mm of the lateral border of the sacrum. The average nerve root width was 6.2 mm (95% CI: 6.13–6.34). An increased sacral length was associated with a larger medial (p<.001) and lateral (p<.001) safe zone. CONCLUSIONSOur study revealed lateral and medial safe zones for the placement of S1 pedicle screws to avoid iatrogenic nerve injury in a retrospective cohort of 400 patients. There were no L5 nerve roots found within 22.3 mm of the sacrum's mid-axis or within 5.3 mm of the sacrum's anterolateral border. These defined safe zones can be used during pedicle screw planning and placement to decrease the risk of injury to the L5 nerve root.

Correlation between bone mineral density of different sites and lumbar disc degeneration in postmenopausal women.

Osteoporosis and lumbar disc degeneration (LDD) have been common causes that make increasing patients suffer from different degrees of low back pain. At present, whether osteoporosis degenerates or protects disc is still controversial, and the correlation between hip bone mineral density (BMD) and LDD still remains unclear. Our study aims to analyze the correlation between BMD of different sites and LDD in postmenopausal women, and explore the potential pathophysiological mechanism of them.One hundred ninety-five postmenopausal female patients were enrolled and divided into osteoporosis, osteopenia, and normal bone mass groups. Their BMD and lumbar spine magnetic resonance imaging were retrospectively analyzed. Two spine surgeons were selected to assess LDD according to Pfirrmann grading system.Based on lumbar BMD, LDD of normal bone mass group was more severe than the other 2 groups in L1/2 and L2/3 segments (P < .05). Based on hip BMD, LDD of each disc from L1/2 to L5/S1 had no significant difference among the 3 groups (P > .05). Lumbar BMD (L1-L4) was positively correlated with corresponding degree of LDD (L1/2-L4/5) (P < .05), whereas there was no correlation between hip BMD and degree of LDD (P = .328).There is a positive correlation between lumbar BMD and LDD in postmenopausal women, which is more obvious in the upper lumbar spinal segments (L1, L2). However, there is no correlation between hip BMD and LDD, suggesting that in postmenopausal women with lumbar degenerative disease, hip BMD is more suitable for the diagnosis of osteoporosis.

Normative Data and Reproducibility for Vertebral Bone Quality Score in Serial Lumbar Spine Magnetic Resonance Imaging

The vertebral bone quality (VBQ) score can independently predict fragility fractures and is useful for osteoporosis screening. It is derived by taking the ratio of the median L1-L4 signal intensity (SI) and L3 cerebral spinal fluid SI on opportunistic T1 weighted (fat sensitive) magnetic resonance imaging (MRI) scans. Higher VBQ score indicates more fat and less bone suggesting osteoporosis. Normative data has not been described. The purpose of this study was to determine whether VBQ score increased with age and remained consistent across serial MRI studies. This retrospective study evaluated 107 lumbar spine patients, age 20-69, who received two T1-weighted MRI within three months of each other between January 2011 and December 2021. Patients were divided into cohorts by decade of life. Patients with prior vertebral fracture, spinal metastasis, instrumentation at two or more levels, and MRI scans with spin sequences outside the optimal range for bone marrow analysis (TR=400-850, TE=8-20) were excluded. Regression analysis was performed to determine correlation of VBQ score with age. Interclass correlation (ICC) was calculated to determine reproducibility between VBQ scores derived from separate MRI scans. 53 males and 54 females were included in the study. 90% were Caucasian. The mean VBQ scores for the first and second set of MRI scans were 2.39±0.74 and 2.30±0.88, 2.68±0.57 and 2.54±0.74, 2.56±0.63 and 2.70±0.69, 2.99±0.72 and 2.77±0.89, 3.27±0.57 and 3.21±0.60 for the age ranges of 20-29, 30-39, 40-49, 50-59, 60-69, respectively. Among males, age positively correlated with VBQ scores measured from the first (r=0.361, p=0.008) and second (r=0.286, p=0.038) MRI scans. Among females, age likewise positively correlated with VBQ scores measured from the first (r=0.395, p=0.003) and second (r=0.398, p=0.003) MRI scans. For the entire cohort, the ICC=0.749. VBQ score is positively correlated with age. The majority of patients age > 50 had VBQ > 3.00, further supporting this threshold as a diagnostic cutoff for potential osteoporosis and additional bone health evaluation. Reproducibility of the VBQ score across serial MRI is good, which supports the possible usefulness of the VBQ score in the pre-operative evaluation of spine surgical patients.

ISSLS prize in clinical science 2022: accelerated disc degeneration after pubertal growth spurt differentiates adults with low back pain from their asymptomatic peers

PurposeIn this prospective observational cohort study, the development of lumbar intervertebral discs (LIVD) on magnetic resonance imaging (MRI) was investigated from childhood to adulthood with emphasis on the possible association of disc degeneration (DD) to low back pain (LBP).MethodsIn 2021, 89 subjects who were enrolled in 1994 in a longitudinal study with lumbar spine MRI at ages 8, 11 and 18 were invited to participate in a long-term follow-up comprising a clinical examination, selected patient-reported outcome measures and a lumbar spine MRI. We assessed all MRIs (three lowest LIVDs) with the Pfirrmann summary score, and the ratio of signal intensity of nucleus pulposus to signal intensity of cerebrospinal fluid (SINDL). We further analyzed whether disc changes at any age were associated with self-reported LBP at age 34.ResultsOf the 48 subjects in the follow-up, 35 reported LBP at age 34. The Pfirrmann summary score significantly increased with age (p < 0.001). Subjects reporting LBP at age 34 demonstrated statistically significantly higher summary scores at age 18 and 34 compared to asymptomatic subjects (p = 0.004 at age 18, and p = 0.039 at age 34). SINDL significantly decreased with age (p < 0.001 for all levels separately), but no significant differences between subjects with or without LBP at age 34 were noticed.ConclusionSubjects with LBP at age 34 had more widespread or severe DD already at age 18 compared to those without LBP.

Case Report: Predominant brain superficial location of Epstein-Barr virus-related primary central nervous system diffuse large B cell lymphoma in a young woman with primary Sjögren’s syndrome

Epstein-Barr virus (EBV)- related primary central nervous system (CNS) diffuse large B cell lymphoma (DLBCL) is very rare in young patients without immunodeficiency. The predominant brain superficial location of EBV-related primary CNS DLBCL, and its’ concurrence with EBV-related lumbar-sacral radiculitis are special and have not been described previously. A young female patient presented with multiple cranial neuropathies, radiculopathy of lower limbs, and urinary retention. Her series brain magnetic resonance imaging (MRI) revealed dynamic changes, starting from lesions mainly in cranial nerves to mammillary body, pineal body, meninges, and finally in the bilateral cerebellum and cerebral lobes. Lumber spinal MRI showed enhancement in meninges and cauda equine roots. 18-fluorodeoxyglucose PET-CT revealed remarkably increased glucose metabolism in the lesions shown on the aforementioned brain MRI and lumbar spinal MRI, as well as right axillary lymph nodes. The biopsy of a whole axillary node on right side indicated EBV-related lymphoproliferation. Lumbar meninges and cauda nerves biopsy revealed chronic inflammation. By cerebral spinal fluid cytology and in situ hybridization, EBV-encoded small RNA (EBER) positive large B cell lymphoma was identified. The patient also had primary Sjögren’s syndrome (PSS). The patient died two weeks after treatment with rituximab, lenalidomide and methylprednisolone. She had survived for four and a half months since symptom onset. The patient presented with several stages of EBV-related complications in the nervous system, chronic EBV infection of lumbar-sacral radiculitis, and primary CNS DLBCL, indicating the process from chronic EBV infection to DLBCL in nervous system. Intracranial acute bacterium infection probably exacerbated the progression of CNS DLBCL. The concomitant sufferings of PSS reflected immune-dysfunction might have increased the risk of EBV-related CNS DLBCL in this young patient.

Multi-scanner and multi-modal lumbar vertebral body and intervertebral disc segmentation database

Magnetic resonance imaging (MRI) is widely utilized for diagnosing and monitoring of spinal disorders. For a number of applications, particularly those related to quantitative MRI, an essential step towards achieving reliable and objective measurements is the segmentation of the examined structures. Performed manually, such process is time-consuming and prone to errors, posing a bottleneck to its clinical applicability. A more efficient analysis would be achieved by automating a segmentation process. However, routine spine MRI acquisitions pose several challenges for achieving robust and accurate segmentations, due to varying MRI acquisition characteristics occurring in data acquired from different sites. Moreover, heterogeneous annotated datasets, collected from multiple scanners with different pulse sequence protocols, are limited. Thus, we present a manually segmented lumbar spine MRI database containing a wide range of data obtained from multiple scanners and pulse sequences, with segmentations of lumbar vertebral bodies and intervertebral discs. The database is intended for the use in developing and testing of automated lumbar spine segmentation algorithms in multi-domain scenarios.

Lumbar Spine Computed Tomography to Magnetic Resonance Imaging Synthesis Using Generative Adversarial Network: Visual Turing Test.

(1) Introduction: Computed tomography (CT) and magnetic resonance imaging (MRI) play an important role in the diagnosis and evaluation of spinal diseases, especially degenerative spinal diseases. MRI is mainly used to diagnose most spinal diseases because it shows a higher resolution than CT to distinguish lesions of the spinal canals and intervertebral discs. When it is inevitable for CT to be selected instead of MR in evaluating spinal disease, evaluation of spinal disease may be limited. In these cases, it is very helpful to diagnose spinal disease with MR images synthesized with CT images. (2) Objective: To create synthetic lumbar magnetic resonance (MR) images from computed tomography (CT) scans using generative adversarial network (GAN) models and assess how closely the synthetic images resembled the true images using visual Turing tests (VTTs). (3) Material and Methods: Overall, 285 patients aged ≥ 40 years who underwent lumbar CT and MRI were enrolled. Based on axial CT and T2-weighted axial MR images from 285 patients, an image synthesis model using a GAN was trained using three algorithms (unsupervised, semi-supervised, and supervised methods). Furthermore, VTT to determine how similar the synthetic lumbar MR images generated from lumbar CT axial images were to the true lumbar MR axial images were conducted with 59 patients who were not included in the model training. For the VTT, we designed an evaluation form comprising 600 randomly distributed axial images (150 true and 450 synthetic images from unsupervised, semi-supervised, and supervised methods). Four readers judged the authenticity of each image and chose their first- and second-choice candidates for the true image. In addition, for the three models, structural similarities (SSIM) were evaluated and the peak signal to noise ratio (PSNR) was compared among the three methods. (4) Results: The mean accuracy for the selection of true images for all four readers for their first choice was 52.0% (312/600). The accuracies of determining the true image for each reader’s first and first + second choices, respectively, were as follows: reader 1, 51.3% and 78.0%; reader 2, 38.7% and 62.0%, reader 3, 69.3% and 84.0%, and reader 4, 48.7% and 70.7%. In the case of synthetic images chosen as first and second choices, supervised algorithm-derived images were the most often selected (supervised, 118/600 first and 164/600 second; semi-supervised, 90/600 and 144/600; and unsupervised, 80/600 and 114/600). For image quality, the supervised algorithm received the best score (PSNR: 15.987 ± 1.039, SSIM: 0.518 ± 0.042). (5) Conclusion: This was the pilot study to apply GAN to synthesize lumbar spine MR images from CT images and compare training algorithms of the GAN. Based on VTT, the axial MR images synthesized from lumbar CT using GAN were fairly realistic and the supervised training algorithm was found to provide the closest image to true images.

An investigation of lumbar spine magnetic resonance referrals in two Irish university teaching centres: Radiology clinical judgement versus iRefer guideline compliance

IntroductionWith the annual increase in medical imaging demand, the appropriateness of the lumbar spine magnetic resonance imaging LSMRI referrals is worldwide gaining attention. This study aims to determine the appropriateness of LSMRI referrals and compare radiology clinical decisions to iRefer compliance based solely on referral text content. MethodsReferral text was extracted from 1021 LSMRI referrals. Two review panels were recruited: three expert radiologists and three MRI radiographers. Radiologists classified cases as indicated or not indicated for scanning based on their clinical judgement. The radiographers classified based solely on iRefer guidelines. Majority voting for each case was applied to both review panels and reviewer agreement was tested using Kappa analysis. Logistic regression models were developed to identify medical disciplines associated with high rates of indicated referrals. Results21.7% and 11.9% of the cases were found not indicated for MRI for radiologists and radiographers, respectively. Radiology review identified 18% of the GPs referrals as not indicated and 17% in the radiographers’ review. Panel agreement was fair: Kappa values of 0.23 and0.26 for the radiologists and radiographers respectively. Neurosurgery was associated with the highest rate of indicated referrals across both review panels: oncology referrals raised the highest number of open comments. ConclusionThe study identified a lower number of not indicated referrals compared to previous research. Findings indicate the importance of both guidelines compliance and clinical judgement to optimise practice. Implications for practiceFindings in this study found that even when strict instructions were given to the MR radiographers to vet referrals using the iRefer guidelines, ambiguity within the guidelines resulted in variations in decision-making. This suggests that detailed protocols are required to support radiographers in the vetting process to ensure a standardised approach.

Can routine MRI spine T1 sequences be used for prediction of decreased bone density?

Bone marrow signal is ideally evaluated with magnetic resonance imaging (MRI) due to its high tissue contrast. While advanced MRI quantitative methods can be used for estimating bone density, there are no readily available parameters on routine clinical MRI sequences of the lumbar spine. To evaluate whether T1 signal intensity (SI) ratio of lumbar vertebral body (VB)/cerebrospinal fluid (CSF) may predict decreased bone density. A retrospective study was conducted. After use of inclusion/exclusion criteria, 36 patients who had an MRI scan of the lumbar spine and a DEXA scan performed as a part of annual health visit were selected. T1 SI of the lumbar vertebral bodies and adjacent CSF were recorded. Ratio of T1 SI of L1-L4 (VB)/CSF was calculated. The corresponding bone-density values on DEXA scan measured as g/cm2 were obtained. Pearson's r correlation statistic was used to determine the correlation between these variables. T1 VB/T1 CSF SI ratio was between 1.308 and 2.927 (mean = 2.028). Mean T1 SI value of vertebral bodies (L1-L4) was 264.9 and mean CSF SI value was 131.9. Bone density in g/cm2 was between 0.851 and 1.398 (mean = 1.081). Pearson correlation coefficient was r = -0.619 (P=0.0001), which shows a negative moderate correlation between the T1 VB/T1 CSF SI ratio and bone density. A high T1 VB/T1 CSF SI ratio on routine MRI sequences may indicate decreased bone density. This ratio may be of substantial benefit in unsuspected osteoporosis/osteopenia on routine MRI lumbar spine imaging.

Machine learning and deep learning-based Natural Language Processing for auto-vetting the appropriateness of Lumbar Spine Magnetic Resonance Imaging Referrals

Manual vetting of radiology referrals is an essential daily task to ensure the appropriateness of the received referrals. Such tasks require sufficient clinical experience and may challenge the radiology staff. With the emerging of artificial intelligence (AI) technology and advancement in natural language processing NLP, most of the available machine learning-based NLP models targeted research cohort building and healthcare quality. Other healthcare management tasks such as auto-vetting radiology referrals have not been adequately encoded. Furthermore, challenges, including class imbalance and lack of direct comparison with humans, are yet to be investigated sufficiently. In this study, a set of machine learning and deep learning models were developed for auto-vetting of lumbar spine magnetic resonance imaging LSMRI referrals as indicated or not indicated for scanning using referrals from two hospitals. The impact of applying one of the text augmentation techniques on the models' performance has been investigated. In addition, the performance of four different feature extraction techniques has been critically analyzed. Moreover, a comparison has been conducted between the developed models with two expert radiologists who were not involved in establishing the gold standard labels using an unseen dataset. The results show that the models’ performances significantly improved with the augmented data, with an increase in F1 scores ranging from 1% to 8%. Support vector machine with bag of words achieved the highest AUC reaching 0.99. Convolutional neural network model achieved the second-highest model with AUC = 0.97. All models outperformed the two expert radiologists when comparisons were conducted on the unseen dataset.

Prevalence and clinical potential of extraspinal incidental findings in lumbosacral spine MRI of patients with suspected disc diseases

BACKGROUND Incidental findings could be observed in organs close to the spine while reporting lumbosacral spine magnetic resonance imaging (MRI). This study aimed to report the prevalence and clinical potential of extraspinal incidental findings in lumbosacral MRI of patients with suspected disc diseases.&#x0D; METHODS This single-centered cross-sectional study was carried out on 420 consecutive adult patients who underwent lumbar spine MRI for suspected disc disease from January to July 2019. The MRI was checked for the presence of extraspinal incidental findings, and each finding was categorized according to the body organ and its clinical significance. Each MRI plane that best displayed the findings was recorded, and the association between the findings and patient's age and sex was determined.&#x0D; RESULTS Of 420 samples, 135 cases showed extraspinal findings (32.1%), and 7.6% of the patients displayed suspicious lesions. The urinary tract was the most common system (18.6%) to display both clinically significant (5.0%) and benign findings (13.6%), and the axial MRI section was the plane which showed most of the incidental findings. Incidental findings in any body system were rarely found in the younger patients. Females had significantly higher benign findings than males (p = 0.002).&#x0D; CONCLUSIONS The prevalence of extraspinal findings in lumbosacral spine MRI is high, and some are significant. Most findings are related to the urinary tract and best displayed in the axial plane.

Finite Element Analysis of a Bionate Ring-Shaped Customized Lumbar Disc Nucleus Prosthesis.

Study design: Biomechanical study of a nucleus replacement with a finite element model. Objective: To validate a Bionate 80A ring-shaped nucleus replacement. Methods: The ANSYS lumbar spine model made from lumbar spine X-rays and magnetic resonance images obtained from cadaveric spine specimens were used. All materials were assumed homogeneous, isotropic, and linearly elastic. We studied three options: intact spine, nucleotomy, and nucleus implant. Two loading conditions were evaluated at L3-L4, L4-L5, and L5-S1 discs: a 1000 N axial compression load and this load after the addition of 8 Nm flexion moment in the sagittal plane plus 8 Nm axial rotation torque. Results: Maximum nucleus implant axial compression stresses in the range of 16–34 MPa and tensile stress in the range of 5–16 MPa, below Bionate 80A resistance were obtained. Therefore, there is little risk of permanent implant deformation or severe damage under normal loading conditions. Nucleotomy increased segment mobility, zygapophyseal joint and end plate pressures, and annulus stresses and strains. All these parameters were restored satisfactorily by nucleus replacement but never reached the intact status. In addition, annulus stresses and strains were lower with the nucleus implant than in the intact spine under axial compression and higher under complex loading conditions. Conclusions: Under normal loading conditions, there is a negligible risk of nucleus replacement, permanent deformation or severe damage. Nucleotomy increased segmental mobility, zygapophyseal joint pressures, and annulus stresses and strains. Nucleus replacement restored segmental mobility and zygapophyseal joint pressures close to the intact spine. End plate pressures were similar for the intact and nucleus implant conditions under both loading modes. Manufacturing customized nucleus implants is considered feasible, as satisfactory biomechanical performance is confirmed.

Psoas muscle index is related to hip fracture in osteoporosis: a cross-sectional MRI study.

The aim of this study was to investigate the properties of psoas muscle in osteoporotic patients in lumbar magnetic resonance imaging (MRI) scan and their relationship with hip fracture. One hundred seventy-seven patients with osteoporosis (63.69 ± 9.677, 105 female) who had received lumbar spine MRI and dual-energy X-ray absorptiometry (DXA) examinations were retrospectively included. Thickness (PMT), cross-sectional areas (CSA), and index (PMI) values were measured for psoas muscle at L3 level and psoas muscle characteristics were compared between hip fracture and control groups. PMT, CSA, and PMI values were statistically significantly different between hip fracture and control groups (respectively p < .001, p < .05, p < .01). The results showed that there was a significant association between being sarcopenic and having hip fracture (χ2 (1, n = 117) = 4.57, p < .05, phi = .20). PMT, CSA, and PMI might be associated with hip fracture in osteoporotic patients. However, this association is independent of bone mineral density (BMD). Psoas muscle features including PMT, CSA, and PMI should be used as significant predictors of falls and fractures in osteoporotic patients.

Fifth lumbar vertebrae solitary osteochondroma arising from the neural arch, a case report

BackgroundOsteochondromas are a benign outgrowth of bone and cartilage and one of the most common bone tumors that usually occur in long bones, with only 1–4% being located in the spine, more frequently in the cervical and upper dorsal region, and rarely the lumbar spine. Here, we report a case of lumbar spine (L5) osteochondroma arising from the neural arch.Case presentationA 30-year-old man presenting with a solid painless mass at the lower lumbar region. No neurological symptoms. Radiological examinations revealed an exophytic lesion in the fifth lumbar articular process, and the spinous process appears to be a solitary osteochondroma. Lumbar spine magnetic resonance imaging showed a bony lesion covered by a 2-mm-thick cartilaginous cap. Surgical en bloc resection of the mass was performed, and the histopathological examination confirmed the diagnosis of osteochondroma. No evidence of recurrence at the end of 4-year follow-up.ConclusionOsteochondromas are benign tumors rarely present in the spine; diagnosis can be made by the typical appearance of the cartilaginous cap over the mass in the magnetic resonance imaging. Surgical excision is the best management option.

Safety of 3 Tesla Magnetic Resonance Imaging in Patients With Auditory Brainstem Implants.

To evaluate the safety of 3 Tesla (T) magnetic resonance imaging (MRI) in patients with auditory brainstem implants (ABI) with the magnet removed at implantation and report incidence of complications. Retrospective chart review. Tertiary neurotology ambulatory practice. Patients with diagnosis of Neurofibromatosis, type 2 (NF2) with functional ABIs. Observational recordings. Of the 89 patients meeting inclusion criteria, 7 patients underwent 3T MRI, with a total of 39 scans done. Three patients had 1 scan each, one patient had 4 scans, one patient had 5 scans, one patient had 6 scans, and one patient had 21 scans. The mean time between ABI placement and first 3 T scan was 118 ± 73 months. The most common indication for imaging was surveillance of NF2 lesions. The most frequent scans were MRI brain (25.6%), followed by MRI of cervical (15%), thoracic (15%) and lumbar (15%) spine, and MRI IAC (8%). There were no reported complications for any of the scans. No scans were interrupted due to patient discomfort. There were no device malfunctions. 3 T MRIs are safe in patients with ABIs as long as the magnet is removed. It is recommended that the magnet be removed at the time of implantation in all NF2 patients, who require frequent surveillance.

What Causes the Discrepancy between Quantitative Computed Tomography and Dual Energy X-Ray Absorptiometry?

Objective: Dual energy X-ray absorptiometry (DXA) is a standard tool for measuring the bone mineral density (BMD), but it sometimes provides inaccurate results. In contrast, quantitative computed tomography (QCT) measures the BMD more accurately by directly measuring the trabecular bone. This study examined the factors that cause the discrepancy between DXA and QCT with advanced spinal imaging.Methods: The medical records of 59 patients who underwent DXA, QCT, and a lumbar spine magnetic resonance imaging (MRI) were reviewed retrospectively. The following values were measured on plain radiographs, computed tomography, and MRI: lumbar lordosis, segmental scoliosis, compression fracture, spondylosis, abdominal aortic calcification, facet joint degeneration, and Modic change. The significant parameters contributing to the discordance results between DXA and QCT were evaluated by logistic regression analysis.Results: QCT identified osteoporosis in 43 patients (72.88%). DXA identified 15 osteoporotic patients (25.42%). Of the 44 patients not diagnosed with osteoporosis by DXA, 30 patients (68.18%) were diagnosed with osteoporosis by QCT. Multivariate logistic regression analysis showed that the result of DXA might be overestimated by a degenerated facet joint (odds ratio [OR] 4.58; 95% confidence interval [CI], 1.1-19.07) and measurements at a fracture site (OR, 1.63; 95% CI, 1.23-2.15).Conclusion: DXA might miss a diagnosis of osteoporosis. Facet joint hypertrophy due to degeneration revealed a stronger association with the overestimation of the BMD by DXA than the formation of osteophytes at the vertebral body. Therefore, the results of DXA should be interpreted carefully, considering the possibility of interruption.

Excruciating Low back Pain in an Acute Stroke Patient: A Case Report

Background: Acute low back pain is one of the most common reasons for adults to see a physician. However, vertebral osteomyelitis (VO) is a rare condition, which mostly affects the lumbar spine. Lumbar spine MRI imaging is the diagnostic method of choice. If left untreated can lead to vertebral destruction or spinal abscess formation. Case: An 86-year-old man presented with a stroke to our facility, while undergoing therapy complained of excruciating low back pain that prevented him from undergoing therapy specially standing and walking. His vital signs were normal, and he was afebrile. Plain X-ray of the lower spine showed osteoarthritic changes. Patient was initially started on non-steroidal anti-inflammatory (NSAID) with no change in the severity of his low back pain. Lumbar vertebral spine magnetic resonance imaging (MRI) showed lumbar vertebral osteomyelitis. Initiation of IV antibiotics dramatically decreased the pain severity. Conclusion: Low back pain is common in the elderly population and responds effectively to NSAID. Persistence of low back pain in the presence of pathognomonic changes in the lumbar spine MRI indicate the presence of VO. Prompt treatment with empirical antibiotics is warranted.

Intradiscal vacuum phenomenon and spinal degeneration: a cross-sectional analysis of 219 subjects

Introduction Intradiscal vacuum phenomenon (IVP) is the collection of gas within the intervertebral discs. It has been reported with various spinal disorders. The exact role of IVP in spinal degeneration leading to low back pain (LBP) is unclear. We aimed to obtain the prevalence of IVP in patients with LBP. Our second aim was to understand whether IVP was associated with intervertebral disc degeneration (IVDD), Modic changes, and subchondral sclerosis (SS). Methods A total of 12.450 consecutive patients with chronic LBP were evaluated in terms of having abdominal computed tomography (CT) scan concomitant with lumbar spine magnetic resonance imaging (MRI) using radiological database of three spine centers. We excluded the patients with a history of malignancy, metabolic disease, spinal infection, traumatic or osteoporotic spine fracture, and spine surgery. All lumbar levels were evaluated in terms of IVDD and Modic changes on MRI, while they were evaluated in terms of IVP and SS on CT scans. Results We included 219 patients. Severe IVDD, Modic changes, IVP, and SS were seen in 53.9% (n: 118), 38.8% (n: 85), 26.5% (n: 58), and 16% (n: 35) of the patients, respectively. Intradiscal vacuum phenomenon was closely associated with severe IVDD (OR: 8.204), Modic changes (OR: 3.547) and SS (OR: 4.231). Discussion Intradiscal vacuum phenomenon was closely associated with severe IVDD, Modic changes, and SS. Further prospective clinical and laboratory studies are necessary to better delineate the pathogenesis of IVP.

Reliability and validity of subjective radiologist reporting of temporal changes in lumbar spine MRI findings.

The importance of lumbar findings on magnetic resonance imaging (MRI) remains controversial. Changes in lumbar MRI findings over time may provide important insights into the causes of low back pain. However, the reliability and validity of temporal changes are unknown. To (1) investigate the interrater reliability of subjective radiologist reporting of temporal changes in lumbar spine MRI findings and (2) determine how commonly temporal changes are reported when two scans are conducted 30 minutes apart (considered false positives). Cross-sectional study. Radiology clinic. Forty volunteers (mean age 40; 53% female) with current (n=31) or previous (n=9) low back pain underwent initial lumbar MRI on a single 3T scanner. Participants then lay on a bed for 30 minutes before undergoing an identical MRI. In addition, we purposely selected five participants from a previous study with repeat lumbar MRI scans where temporal changes were reported in at least one MRI finding (1-12 weeks after initial scan) and another five participants where no temporal change was reported. The 10 participants were included in analyses for aim 1 only. Not applicable. Two blinded radiologists reported on temporal changes between the baseline and repeat scan for 12 different MRI findings (eg, disk herniation, annular fissure) at five levels. The interrater reliability of subjective reporting of temporal changes was poor for all MRI findings based on Kappa values (≤ 0.24), but agreement was relatively high (≥ 90.8%). This is explained by the low prevalence of temporal changes as demonstrated by high values for Prevalence and Bias Adjusted Kappa (≥ 0.82). "False positive" temporal changes were reported by at least one radiologist for most MRI findings, but the rate was generally low. Caution is required when interpreting temporal changes in lumbar MRI findings owing to low reliability and some false positive reporting.