Axial Magnetic Resonance Imaging Research Articles

A Nomogram for Predicting Late-Onset Neurological Deficits in the Natural Course of Kyphosis or Kyphoscoliosis.

Retrospective single-center comparative analysis. To develop a nomogram model for predicting late-onset neurological deficits (LONDs) in patients with kyphosis or kyphoscoliosis. Patients with kyphosis or kyphoscoliosis might suffer from LONDs, and surgical correction may improve neurological function. Nevertheless, there exists a significant gap in the identification of predictive factors for LONDs in these patients. A consecutive series of 244 patients with kyphosis or kyphoscoliosis who underwent corrective surgery between April 2010 and June 2024 were included in our study. Relevant measurements, including the Cobb angle, deformity angular ratio (DAR), and level of the apex were assessed and calculated using X-ray imaging. Spinal cord morphology at the apex of the major curve was evaluated using preoperative axial T2-weighted magnetic resonance imaging (MRI) to categorize patients into three types based on the spinal cord shape classification system (SCSCS). To identify independent risk factors associated with LONDs, we employed univariate analysis followed by backward stepwise multivariate logistic regression analysis. A nomogram was established based on the identified independent risk factors to predict the likelihood of LONDs in patients with kyphosis or kyphoscoliosis. The mean age of the 244 patients was 46.4±17.8 years, with an observed incidence of LONDs at 57.8%. The backward stepwise multivariate logistic regression analysis indicated that age, etiological diagnosis and SCSCS were independent predictors of LONDs. Utilizing these independent risk factors, we constructed a nomogram model to estimate the probability of LONDs. The concordance index (C-index) of the model was 0.912 (95% CI, 0.876-0.947), indicating a satisfactory level of accuracy in predicting the likelihood of LONDs. The predictive factors for LONDs include age, etiological diagnosis and SCSCS. We developed a nomogram model to predict LONDs, which could be useful for patient counseling and facilitating treatment-related decision-making.

A magnetic resonance imaging-based morphometric analysis of bilateral L1-L5 oblique lumbar interbody fusion corridor: feasibility of safe surgical approach and influencing factors.

Retrospective cross-sectional study. To investigate the size and local anatomy of the right and the left-sided oblique corridors between L1-L5 levels and identify the potential impact of increasing age and sex on corridor size. The oblique lumbar interbody fusion (OLIF) was introduced by Silvestre and his colleagues as a solution to the approach-related complications associated with anterior lumbar interbody fusion and lateral lumbar interbody fusion. Limited data were available describing the local anatomy and morphology of this approach. Imaging data of 300 patients (150 males and 150 females) who underwent 1.5T magnetic resonance imaging (MRI) scans of the lumbar spine at Indian Spinal Injuries Centre, New Delhi, India between January 2023 and January 2024 were retrospectively reviewed. The cohort was stratified into six age groups (21-30, 31-40, 41-50, 51-60, 61-70, and >70 years) with 25 patients in each age group for both sexes. T2 weighted axial MRI images were analyzed from the L1-L5 level at the mid-disc level to calculate the corridor size. The local anatomical differences were recorded. At L1-L2, L2-L3, L3-L4, and L4-L5 levels, the mean corridor sizes in males were 17.48, 15.50, 13.41, and 9.32 mm on the left side, and 11.48, 7.12, 4.34, and 1.64 mm on the right side, respectively. The corresponding mean corridor sizes in females were 10.34, 12.94, 12.64, and 7.22 mm on the left side and 2.66, 3.52, 3.69, and 1.64 mm on the right side, respectively. For both sides, the corridor size was significantly affected by sex, increased with age, and decreased at the lower lumbar disc levels. A left-sided OLIF approach is more feasible for both sexes. The right-sided approach is less likely to be performed effectively.

A novel radiographic finding for estimation of the cortical-cancellous boundary: A magnetic resonance imaging case series of patients with femoroacetabular impingement

PurposeTo determine if comparing alpha angle measurements of the outer cortical margin (preoperative alpha angle) and the inner cortical margin (theoretical postoperative alpha angle) on magnetic resonance imaging (MRI) can estimate the amount of sclerotic bone that needs to be resected to restore the alpha angle to normative values (<55⁰) in patients with symptomatic femoroacetabular impingement (FAI). MethodsA retrospective review was conducted on patients with FAI undergoing primary hip arthroscopy and CAM osteoplasty from June 2013 to February 2017. Inclusion criteria were radiologist-measured alpha angles >70° on 3T oblique axial MRI, unilateral primary hip arthroscopy, and age ≥18. Exclusions included previous hip surgery, hip trauma, avascular necrosis, advanced osteoarthritis, dysplasia, poor quality images, or missing MRI images. Alpha angles were measured preoperatively using the outer cortical margin and postoperatively using the inner cortical margin of femur. Surgeries were performed by the senior surgeon. Paired t-tests compared preoperative and postoperative alpha angles, and intraclass correlation coefficients (ICC) were used to assess inter-rater and intra-rater reliability. ResultsOne hundred patients (100 hips) were included with an average age of 40.8 years (range, 18.7–64.9), with 75 % being male (n = 75). The average BMI was 24.7 ± 3.9 (range, 17.1–38.8). The average maximum alpha angle at the outer cortical margin was 77.0 ± 4.2° (range, 70.0–90.8), with an ICC for inter-rater reliability of 0.861, indicating excellent agreement. The average inner cortical alpha angle was 46.4 ± 3.4° (range, 36.5–55.4), significantly less than 55° (p<0.001). The mean difference between the outer and inner cortical alpha angles was −30.6 ± 5.1° (p< 0.001). ConclusionsThe difference between outer and inner cortical alpha angles on MRI can accurately estimate the amount of sclerotic bone resection needed to restore the alpha angle to normative values in patients with FAI. This information may be directly applied clinically marker to assess adequacy of CAM resection.

Magnetic Resonance Imaging-Based Radiomics of Axial and Sagittal Orientation in Pregnant Patients with Suspected Placenta Accreta Spectrum

Rationale and ObjectivesPlacenta accreta spectrum (PAS) is associated with significant morbidity and mortality. Current radiomic analysis of PAS magnetic resonance (MR) images is often performed on a single imaging plane. However, depending on the chosen imaging plane, radiomic features extracted from the same patient may vary due to the differing orientations and anatomical contexts, potentially leading to inconsistent results. In this study, we applied region of interest (ROI)-based radiomic analysis on axial and sagittal MR images in pregnant patients at high-risk for PAS. Our objective was to compare MR textural features extracted from these imaging planes and to correlate these findings with surgical outcomes, aiming to enhance the accuracy of PAS diagnosis and treatment planning. Materials and MethodsThis is a retrospective review of MR images of pregnancies with prenatally suspected PAS. Volumetric placental, uterus, and internal os of the cervix regions of interest (ROI) were manually segmented on axial and sagittal MR images for each patient. Radiomic features were extracted following the image biomarker standardization initiative guideline. Agreement in features extracted from axial and sagittal images were assessed using Spearman’s rank correlation coefficient. ResultsOf the 101 pregnant patients that met the study inclusion criteria, 65 underwent cesarean hysterectomy for PAS. Seventy seven percent of the radiomics features had strong Spearman rank correlations (>0.8) between axial and sagittal images, indicating that these imaging planes provide similar radiomics information. The diagnostic performance of features extracted from axial and sagittal planes was quantified under the receiver operating characteristics curve (AUC). We found that axial and sagittal planes have similar performance for the prediction of hysterectomy. Shape elongation, Placental Location within the Uterus (PLU), and heterogeneity features were significant predictors for hysterectomy regardless of the imaging plane. ConclusionOur study found that radiomics features extracted from axial and sagittal MR image plane in the same patient have excellent agreement and strong correlation. We identified several features present in both axial and sagittal images that were predictive in detecting PAS-suspected patient who required hysterectomy. These features may represent the underlying placental pathophysiology.

Application of deep learning reconstruction in abdominal magnetic resonance cholangiopancreatography for image quality improvement and acquisition time reduction

PurposeTo compare deep learning (DL)-based and conventional reconstruction through subjective and objective analysis and ascertain whether DL-based reconstruction improves the quality and acquisition speed of clinical abdominal magnetic resonance imaging (MRI). MethodsThe 124 patients who underwent abdominal MRI between January and July 2021 were retrospectively studied. For each patient, two-dimensional axial T2-weighted single-shot fast spin-echo MRI images with or without fat saturation were reconstructed using DL-based and conventional methods. The subjective image quality scores and objective metrics, including signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of the images were analysed. An explorative analysis was performed to compare 20 patients’ MRI images with site routine settings, high-resolution settings and high-speed settings. Paired t tests and Wilcoxon signed-rank tests were used for subjective and objective comparisons. ResultsA total of 144 patients were evaluated (mean age, 62.2 ± 14.1 years; 83 men). The MRI images reconstructed using DL-based methods had higher SNRs and CNRs than did those reconstructed using conventional methods (all p < 0.01). The subjective scores of the images reconstructed using DL-based methods were higher than those of the images reconstructed using conventional methods (p < 0.01), with significantly lower variation (p < 0.01). Exploratory analysis revealed that the DL-based reconstructions with thin slice thickness and higher temporal resolution had the highest image quality and were associated with the shortest scan times. ConclusionsDL-based reconstruction methods can be used to improve the quality with higher stability and accelerate the acquisition of abdominal MRI.

MOG-antibody-associated transverse myelitis with the H-sign and unusual MRI enhancement: a case report and literature review.

Transverse myelitis is the second most common symptoms in myelin oligodendrocyte antibody-associated diseases (MOGAD), causing obvious clinical manifestation. T2-hyperintense lesions mainly restricted to the gray matter in the spinal cord on axial magnetic resonance imaging, produce the H-sign, which is thought to be the typical finding of MOGAD. Contrast enhancement can be observed in some cases of myelin oligodendrocyte antibody-associated transverse myelitis (MOG-TM). However, reports on the enhancement pattern associated with the H-sign are rarely seen. In this report, we describe a case of pediatric MOG-TM in which the H-sign was observed without enhancement, while the surrounding white matter exhibited enhancement. This pattern contradicts the previously observed gray matter involvement. Then we reviewed the literatures of myelin oligodendrocyte antibody-positive myelitis to focus on the neuroimaging features and discuss the implications of our finding.

Encephalopathy with a reversible lesion in the splenium of the corpus callosum in adults

Background &amp; Objectives: Mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) is a clinical and radiological syndrome with a lesion in splenium of the corpus callosum. This lesion is typically detected in the corpus callosum with magnetic resonance imaging (MRI) and usually disappears within a few weeks. The clinical and radiological features of MERS were evaluated for this study. Methods: Twelve patients were included in the study. They were treated between 2018 and 2021 years. The patients’ demographic and clinical features, laboratory data, treatment and prognoses were documented. Results: There were 7 male and 5 female patients in the series. The mean age was 37.92 ± 15.32 (19–62) years. There was history of upper respiratory tract infection in 7 patients, visual loss episodes in 3 patients, epileptic seizure in 2 patients, arthroplasty in 1 patient, cardiac arrhythmia in 1 patient, and COVID-19 (SARS-CoV-2) infection in 2 patients. Focal lesion was detected in the splenium of the corpus callosum with diffusion-weighted MRI which resolved with repeat diffusion MRI and clinical symptoms improved. Conclusions: Axial diffusion-weighted MRI images show typical splenium ovoid lesion of corpus callosum in patients with MERS. Patients with MERS have a good prognosis. It is important to consider MERS as one of the differential diagnoses in adult patients with fever and cognitive impairment.

A deep learning approach for cervical cord injury severity determination through axial and sagittal magnetic resonance imaging segmentation and classification.

Cross-sectional Database Study. While the American Spinal Injury Association (ASIA) Impairment Scale is the standard for assessing spinal cord injuries (SCI), it has limitations due to subjectivity and impracticality. Advances in machine learning (ML) and image recognition have spurred research into their use for outcome prediction. This study aims to analyze deep learning techniques for identifying and classifying cervical SCI severity from MRI scans. The study included patients with traumatic and nontraumatic cervical SCI admitted from 2019 to 2022. MRI images were labeled by two senior resident physicians. A deep convolutional neural network was trained using axial and sagittal cervical MRI images from the dataset. Model performance was assessed using Dice Score and IoU to measure segmentation accuracy by comparing predicted and ground truth masks. Classification accuracy was evaluated with the F1 Score, balancing false positives and negatives. In the axial spinal cord segmentation, we achieved a Dice score of 0.94 for and IoU score of 0.89. In the sagittal spinal cord segmentation, we obtained Dice score up to 0.9201 and IoU scores up to 0.8541. The model for axial image score classification gave a satisfactory result with an F1 score of 0.72 and AUC of 0.79. Our models successfully identified cervical SCI on T2-weighted MR images with satisfactory performance. Further research is needed to develop more advanced models for predicting patient outcomes in SCI cases.

More negative sagittal tibial tuberosity-trochlear groove distances are correlated with larger patellofemoral chondral lesion size.

The purpose of this study is to assess the association between sagittal tibial tuberosity-trochlear groove (sTT-TG) distance and patellofemoral chondral lesion size in patients undergoing cartilage restoration procedures. A retrospective cohort analysis of patients who underwent an osteochondral allograft transplantation or matrix-induced autologous chondrocyte implantation in the patellofemoral compartment, from 2010 to 2020, were included if they had patellofemoral high-grade lesions, magnetic resonance imaging (MRI) and minimum 2-year follow-up. The preoperative sTT-TG distance was measured independently on axial T2-weighted MRI sequences by two authors, each at least two weeks apart. Intraoperative lesion size was reported according to operative report measurements by the attending surgeon. An interclass correlation coefficient (ICC) was calculated to assess intra- and inter-rater reliability, and categorical data analysis and linear regression models were used to assess the relationship between sTT-TG and lesion size. A total of 80 patients (50 females) with a mean age of 31.5 ± 10.4 years, body mass index of 27.0 ± 5.9 kg/m2 and follow-up of 61.5 ± 21.4 months were included. A total of 107 lesions were present: 63 patients with unipolar (patella = 41, trochlea = 22) and 22 with bipolar lesions. The mean MRI defect size was 1.6 ± 1.0 cm2 and the mean intraoperative defect size was 3.8 ± 2.4cm2. Intra- (ICC: 0.99,0.98) and inter-rater reliability (ICC: 0.96) were excellent for both MRI defect size and sTT-TG measurements. The mean sTT-TG was -4.8 ± 4.9 mm and was significantly inversely related to MRI defect size (-0.45, p < 0.01), intraoperative patellar lesion size (-0.32, p = 0.01), total lesion area (-0.22, p = 0.04), but not trochlear lesion size (-0.09, p = 0.56). Multivariable regression demonstrated a more negative sTT-TG remained an independent variable correlated with larger MRI-measured patellofemoral defect sizes and intraoperative patellar lesions. A more negative sTT-TG was an independent variable correlated with larger patellofemoral lesions in patients undergoing patellofemoral cartilage restoration. Level III, Diagnostic.

Novel case of anastomosing hemangioma of the extradural space: illustrative case.

Anastomosing hemangiomas are benign vascular neoplasms occurring mainly in the genitourinary tract and paraspinal soft tissues. There have been no reported cases of anastomosing hemangiomas occurring in the spinal epidural space; therefore, their clinical and radiological presentations remain unclear. A 55-year-old man presented with progressive back pain and motor and sensory disturbances in both lower extremities. Magnetic resonance imaging (MRI) revealed an extradural lesion at the T4-6 level that extended into the extraspinal region through the left T5-6 intervertebral foramen. Axial MRI revealed that the tumor encircled the spinal cord, with sharp horn-like ends in the intraspinal canal. The patient underwent complete tumor resection with T4-6 laminectomy and left T5-6 foraminotomy. The histopathological diagnosis was an anastomo-sing hemangioma exhibiting anastomosing proliferation of capillary vessels with hobnailed endothelial cells. His symptoms improved, and tumor control was achieved 4 months after surgery without adjuvant therapy. Although rare, anastomosing hemangiomas can occur in the spinal epidural space. Radiologically, the tumors show horn-like projections encircling the spinal cord, which can be diagnostic cues. Anastomosing hemangiomas should be included in the differential diagnosis of spinal epidural tumors, especially when characteristic horn-like projections are present. https://thejns.org/doi/10.3171/CASE24265.

Spine and Sacroiliac Joint Involvement in Newly Diagnosed Patients With Inflammatory Bowel Disease: Clinical and MRI Findings From a Population-Based Cohort.

In patients with inflammatory bowel disease (IBD), co-occurring spondyloarthritis (SpA) leads to poorer outcomes and impaired quality of life, highlighting the importance of early detection and effective treatment. This is the first study to assess the prevalence and distribution of axial symptoms and magnetic resonance imaging (MRI)-detected involvement of the spine and sacroiliac joints (SIJs) in early IBD. Newly diagnosed patients with IBD from a prospective, population-based cohort were consecutively recruited. Rheumatological interview, clinical, ultrasound, and MRI assessment for SIJ and spine inflammatory and structural lesions were made using validated scoring methods and consensus definitions of axial SpA (axSpA). Of 110 patients (ulcerative colitis: 70, Crohn's disease: 40, mean age of 42 years, and 40% male), 48 (44.9%) reported back and/or buttock pain, and 10 (9.1%) had inflammatory back pain. Seventeen (16.7%) patients had MRI findings indicative of axSpA; only 10 of these patients had axial symptoms. Inflammatory MRI lesions were present in SIJs and the spine of 27 (26.5%) and 30 (30.3%) patients, respectively. The Assessment of SpondyloArthritis International Society classification criteria for axSpA were met in 11 (10%) cases. MRI findings typical of axSpA were associated with peripheral joint and entheseal inflammation detected by ultrasound ( P = 0.04). No differences in clinical or imaging findings were found between patients with ulcerative colitis and Crohn's disease. One-in-6 newly diagnosed patients with IBD had MRI findings indicative of axSpA. As 40% of these patients were asymptomatic, this suggests that axSpA is underdiagnosed in early IBD. Multidisciplinary collaboration is essential to ensure early detection of axial inflammation and to enable optimal therapy preventing future structural damage and disability.

Predictors of Hydrocephalus Risk After Stereotactic Radiosurgery for Vestibular Schwannomas: Utility of the Evans Index.

Hydrocephalus after Gamma Knife® stereotactic radiosurgery (SRS) for vestibular schwannomas is a rare but manageable occurrence. Most series report post-SRS communicating hydrocephalus in about 1% of patients, thought to be related to a release of proteinaceous substances into the cerebrospinal fluid. While larger tumor size and older patient age have been associated with post-SRS hydrocephalus, the influence of baseline ventricular anatomy on hydrocephalus risk remains poorly defined. A single-institution retrospective cohort study examining patients who developed symptomatic communicating hydrocephalus after undergoing Gamma Knife® SRS for unilateral vestibular schwannomas from 2011 to 2021 was performed. Patients with prior hydrocephalus and cerebrospinal fluid diversion or prior surgical resection were excluded. Baseline tumor volume, third ventricle width, and Evans Index (EI)-maximum width of the frontal horns of the lateral ventricles/maximum internal diameter of the skull-were measured on axial postcontrast T1-weighted magnetic resonance imaging. A total of 378 patients met the inclusion criteria; 14 patients (3.7%) developed symptomatic communicating hydrocephalus and 10 patients (2.6%) underwent shunt placement and 4 patients (1.1%) were observed with milder symptoms. The median age of patients who developed hydrocephalus was 69 years (IQR, 67-72) and for patients younger than age 65 years, the risk was 1%. For tumor volumes <1 cm3, the risk of requiring shunting was 1.2%. The odds of developing symptomatic hydrocephalus were 5.0 and 7.7 times higher in association with a baseline EI > 0.28 (P = .024) and tumor volume >3 cm3 (P = .007), respectively, in multivariate analysis. Fourth ventricle distortion on pre-SRS imaging was significantly associated with hydrocephalus incidence (P < .001). Patients with vestibular schwannoma with higher baseline EI, larger tumor volumes, and fourth ventricle deformation are at increased odds of developing post-SRS hydrocephalus. These patients should be counseled regarding risk of hydrocephalus and carefully monitored after SRS.

TRUNK MUSCLE MASS MEASURED BY BIOELECTRICAL IMPEDANCE ANALYSIS REFLECTS THE CROSS-SECTIONAL AREA OF THE PARAVERTEBRAL MUSCLES AND BACK EXTENSOR STRENGTH

BackgroundTrunk muscles play an important role in supporting the spinal column. A decline in trunk muscle mass, as measured by bioelectrical impedance analysis (TMM–BIA), is associated with low back pain and poor quality of life.PurposeThe purpose of this study was to determine whether TMM–BIA correlates with quantitative and functional assessments traditionally used for the trunk muscles.MethodsWe included 380 participants (aged ≥ 65 years; 152 males, 228 females) from the Shiraniwa Elderly Cohort (Shiraniwa) study, for whom the following data were available: TMM–BIA, lumbar magnetic resonance imaging (MRI), and back muscle strength (BMS). We measured the cross-sectional area (CSA) and fat-free CSA of the paravertebral muscles (PVM), including the erector spinae (ES), multifidus (MF), and psoas major (PM), on an axial lumbar MRI at L3/4. The correlation between TMM–BIA and the CSA of PVM, fat-free CSA of PVM, and BMS was investigated.ResultsTMMBIA correlated with the CSA of total PVM and each individual PVM. A stronger correlation between TMM–BIA and fat-free CSA of PVM was observed. The TMM–BIA also strongly correlated with BMS.ConclusionTMM–BIA is an easy and reliable way to evaluate the trunk muscle mass in a clinical setting.Conflict of interestNoneSources of fundingNone

Study on the consistency between CT hounsfield units and MRI evaluation of preoperative cervical paraspinal muscular fat infiltration in patients undergoing ACDF

ObjectiveTo explore the feasibility of applying CT Hounsfield Units (HUs) for the assessment of preoperative paraspinal muscle fat infiltration (FI) in different segments in patients who underwent anterior cervical discectomy and fusion (ACDF). To compare the consistency of preoperative paraspinal muscle FI evaluations using MRI and those via CT HUs in patients who underwent ACDF surgery.MethodsNinety-five patients (45 males and 50 females, aged 37‒71 years) who received CT and MRI examinations and underwent ACDF surgery were retrospectively analyzed. In the axial T2-weighted MR images at the median level of the C3/4, C4/5, and C5/6 segments, regions of interests (ROIs) were delineated along the boundaries of the cervical multifidus (MF) and semispinalis cervicis (Scer) muscles. Using the threshold tool in ImageJ software, areas of fat tissue and intermuscular septa within the ROI were quantified. The effective cross-sectional area (ECSA) for each side was obtained by subtracting the areas of fat tissue and intermuscular septa from the total ROI area. The ratio of the fat tissue area to the CSA was then calculated to determine the initial FI value. The depth of subcutaneous fat from the midline spinous process to the epidermis at the median plane of the C4/5 intervertebral disc was measured. The initial FI values were then divided by the depth of fat to determine the post-correction FI value. Using the Picture Archiving and Communication System (PACS), at identical segments and planes, ROIs were delineated using the same method as in MRI under a standard soft tissue window (width of 500 HU, level of 60 HU). The CT HU values were measured within these defined areas. The CT HU values from both sides are summed to obtain the total HU value for the segment. According to whether the measurement results of two sets of data follow a normal distribution, Pearson’s test or Sperman’s test was used to analyze the correlation.ResultsOn MRI, a statistically significant difference was observed in the post-correction FI only at the C3/4 segment compared to the other two segments (P < 0.05). No significant difference in the post-correction FI between the C4/5 and C5/6 segments was noted (P > 0.05). The CT HU results showed a substantial discrepancy between C3/4 and C4/5 segments and between C3/4 and C5/6 segments (P < 0.05), whereas no statistically significant difference was found in the CT HU value between the C4/5 and C5/6 segments (P > 0.05). The consistency analysis revealed a relatively strong correlation between the post-correction FI and CT HU values of the C3/4 and C4/5 segments. Furthermore, a strong correlation was detected in the variations in the measurement outcomes at the C5/6 segment.ConclusionPatients requiring surgical treatment for the cervical spine exhibit varying degrees of FI in paraspinal muscles across different locations and segments. Evaluating the degree of FI in the paraspinal muscles of the cervical spine through CT HU values is feasible. There is considerable consistency between the post-correction FI assessed under MRI and the measurements of CT HU values in evaluating the FI of paraspinal muscles in the cervical spine.

Changes in Intramedullary Increased Signal Intensity on Axial T2-weighted MRI After Laminoplasty for Cervical Spondylotic Myelopathy: A 10-year Follow-up Study.

A retrospective study. To investigate whether the preoperative classification and changes in the intramedullary increased signal intensity (ISI) on axial T2-weighted magnetic resonance imaging (MRI) reflect the postoperative functional outcome in patients after laminoplasty for cervical spondylotic myelopathy (CSM). Although patients with CSM exhibit ISI on axial MRI, the association between ISI (preoperative classification and changes) and surgical outcomes has not been investigated. We retrospectively included patients with CSM who underwent MRI preoperatively and at least 10 years postoperatively after laminoplasty between January 2009 and December 2010. According to axial images for the cervical compressive myelopathy (Ax-CCM) system, the ISI on axial images was classified as follows: type 0, normal; type 1, diffuse; type 2, fuzzy focal; and type 3, discrete focal. Functional outcomes, as measured by the Japanese Orthopaedic Association (JOA) score and JOA recovery rate, were evaluated based on the Ax-CCM classification. Forty-three patients were enrolled. The mean follow-up time was 11.0±1.0 years. At the final follow-up, postoperative changes in the type of ISI were observed in 62.8% of patients. The type of ISI improved in 5 patients (11.6%), remained unchanged in 16 patients (37.2%), and worsened in 22 patients (51.2%). Patients with preoperative type 2 ISI had worse postoperative JOA scores and JOA recovery rates than those with other types. A worse ISI type was related to a lower postoperative JOA score and a lower recovery rate at the final follow-up. Type 2 ISI was associated with poor postoperative symptoms and low postoperative function improvement. ISI changed after laminoplasty in 27 patients (62.8%), and worsened ISI was related to poor surgical outcomes.

A novel adapted MRI-based scheme for Dejour classification of trochlear dysplasia.

To elaborate an optimized scheme for the Dejour classification of trochlear dysplasia based on axial and sagittal MR images and to evaluate its intra- and inter-reader reliability. Over a period of 20months patients with a knee MRI and the diagnosis of trochlear dysplasia were retrospectively included. Exclusion criteria were incomplete examination, qualitatively non-diagnostic examination, post trochlear surgery, missing informed consent for research purposes. Three independent evaluations were performed by two radiologists: first using an established description of the Dejour classification (types A-D) and then two evaluations using a new adapted scheme (types A-D). The adapted scheme includes a shallow trochlea, in type A no spur/no cliff, in type B with spur/no cliff, in type C no spur/with cliff, and in type D with spur/with cliff. One hundred seventy-one knee MRIs (female:65.5%; left side:52.6%) were included with a median age of 34.3years (range:11.3-79.2). Inter-reader reliability using the established description was fair for the four-type-classification (kappa(k) = 0.23; 95%CI:0.11-0.34), fair for differentiation low-grade versus high-grade dysplasia (k = 0.28;0.13-0.43), slight for differentiation spur versus no-spur types (k = 0.20;0.05-0.34). Inter-reader reliability using the adapted scheme was substantial (k = 0.79;0.75-0.83) for the four-type-classification, substantial for differentiation low-grade versus high-grade dysplasia (k = 0.80;0.75-0.85), substantial for differentiation spur versus no-spur presence (k = 0.76;0.71-0.81). Intra-reader reliability was almost perfect for the adapted scheme (k-values: 0.88-0.95; 95%CIs: 0.84-0.98). The novel adapted scheme for Dejour classification shows an almost perfect intra-reader reliability and a substantially higher inter-reader reliability. It may become a helpful tool in the daily diagnostic work of radiologists.

Quantitative Threshold of Intraoperative Radiological Parameters for Suspecting Oblique Lumbar Interbody Fusion Cage Malposition Triggering Contralateral Radiculopathy.

This study aimed to clarify the quantitative threshold of intraoperative radiological parameters for suspecting posterior malposition of the oblique lumbar interbody fusion (OLIF) cage triggering contralateral radiculopathy. We measured the sagittal center and axial rotation angle (ARA) of the cage using postoperative computed tomography (CT) in 130 patients (215 cages) who underwent OLIF. The location of the cage tip was determined from axial magnetic resonance imaging in selected cases based on CT simulations to assess whether the cage was in contact with the contralateral exiting nerve or whether the surgical instruments could contact the nerve during intradiscal maneuvers. The sagittal center of the cages was on average 41.5% from the anterior edge of the endplate (shown as AC/AP value: anterior end plate edge-cage center/anterior-posterior endplate edge ×100%), and posterior cage positioning ≥50% occurred in 14% of the cages. The ARA was -2.9°, and posterior oblique rotation of the cages ≥10° (ARA ≤ -10°) was observed in 13%. CT simulation showed that the cage tip could directly contact the contralateral nerve when the cage was placed deep in the posterior portion ≥50% of the AC/AP values with concomitant posterior axial rotation ≥10° (ARA ≤ -10°), or deep in an extremely rare portion ≥60% of the AC/AP values with posterior axial rotation ≥0° (ARA ≤ 0°). Six percent of the cages (13/215) were placed in these posterior oblique areas (potential contact area: PCA). Three cages in the PCA were in direct contact with the contralateral nerves, and 9 were placed deep just anterior to the nerves. Symptomatic contralateral radiculopathy occurred in 2 cages (2/13/215, 15.3%/0.9%). Two intraoperative radiological parameters (AC/AP and ARA) measurable during OLIF procedures may become practical indicators for suspecting cage malposition in PCA and may be available when determining whether to consider cage revision intraoperatively to a more ventral disc space or anteriorly from the opposite endplate edge.

Automatically Detecting Pancreatic Cysts in Autosomal Dominant Polycystic Kidney Disease on MRI Using Deep Learning.

Pancreatic cysts in autosomal dominant polycystic kidney disease (ADPKD) correlate with PKD2 mutations, which have a different phenotype than PKD1 mutations. However, pancreatic cysts are commonly overlooked by radiologists. Here, we automate the detection of pancreatic cysts on abdominal MRI in ADPKD. Eight nnU-Net-based segmentation models with 2D or 3D configuration and various loss functions were trained on positive-only or positive-and-negative datasets, comprising axial and coronal T2-weighted MR images from 254 scans on 146 ADPKD patients with pancreatic cysts labeled independently by two radiologists. Model performance was evaluated on test subjects unseen in training, comprising 40 internal, 40 external, and 23 test-retest reproducibility ADPKD patients. Two radiologists agreed on 52% of cysts labeled on training data, and 33%/25% on internal/external test datasets. The 2D model with a loss of combined dice similarity coefficient and cross-entropy trained with the dataset with both positive and negative cases produced an optimal dice score of 0.7 ± 0.5/0.8 ± 0.4 at the voxel level on internal/external validation and was thus used as the best-performing model. In the test-retest, the optimal model showed superior reproducibility (83% agreement between scan A and B) in segmenting pancreatic cysts compared to six expert observers (77% agreement). In the internal/external validation, the optimal model showed high specificity of 94%/100% but limited sensitivity of 20%/24%. Labeling pancreatic cysts on T2 images of the abdomen in patients with ADPKD is challenging, deep learning can help the automated detection of pancreatic cysts, and further image quality improvement is warranted.

Importance of lumbar instability in the study of associations between muscle morphology, pain, and disability in chronic low back pain.

The purpose of this study was to (1) evaluate the relationship between lumbar extensor muscle morphology, with pain and disability in patients with chronic low back pain (CLBP) and (2) compare these relationships in subgroup of CLBP with and without lumbar structural segmental instability. This cross-sectional study included 183 patients with CLBP. Standing lateral lumbar flexion/extension radiographs were used to assess lumbar structural segmental instability. Lumbar multifidus (MF), erector spinae (ES), and psoas major (PM) morphology were determined from axial magnetic resonance imaging. Associations between lumbar muscle morphologies and patient pain and disability were evaluated in two groups with and without lumbar instability. Patients' disability was negatively associated with PM total cross-sectional area (beta = -22.82, 95%CI = -37.05 to -8.59) and functional cross-sectional area (beta = -23.45, 95%CI = -37.81 to -9.09). MF morphology was negatively associated with disability in the lumbar instability group. Pain intensity was only associated to PM total cross-sectional area (Beta = -3.33, 95%CI = -6.43 to -2.24) and functional cross-sectional area (Beta = -3.22, 95%CI = -6.40 to -0.05) only in the lumbar instability group. PM atrophy was associated with greater disability and pain in CLBP, but MF atrophy was associated with greater disability in CLBP patients with lumbar structural segmental instability.

Initiation of vedolizumab did not provoke new-onset spondylarthritis in patients with inflammatory bowel disease: A prospective 24-week study with imaging assessments.

A temporal relationship between vedolizumab and new-onset spondyloarthritis (SpA) has been suggested. We evaluated the relationship between vedolizumab initiation and development of new-onset SpA in patients with inflammatory bowel disease (IBD) through serial clinical evaluation and magnetic resonance imaging (MRI). A single-centre prospective observational study of 24 patients with IBD. Patients were eligible if they had active ulcerative colitis or Crohn's disease (CD), were initiating vedolizumab, had no prior history of arthritis or SpA and were suitable for serial MRI. A rheumatologist performed clinical evaluation prior to the first dose and 8 and 24weeks. Axial MRI was evaluated by a blinded central reader and performed at baseline 8 and 24weeks. Nine tumor necrosis factor (TNF) inhibitor-naïve patients (4 male; mean age 53.2years; 6 UC; 3 CD) and eight TNF inhibitor-experienced patients (7 male; mean age 48years; 3 UC; 5 CD) completed all assessments. No patients developed new features of axial arthritis or features of peripheral SpA (inflammatory oligoarthritis, enthesitis, dactylitis, or psoriasis (nail, body, or scalp)). Both groups demonstrated a good intestinal response. Vedolizumab initiation did not induce new features of axial or peripheral SpA after 24weeks of treatment in TNF inhibitor-experienced or TNF inhibitor-naive patients with IBD.