Axial Magnetic Resonance Imaging Images Research Articles

Using Marker-Controlled Watershed Transform to Detect Baker's Cyst in Magnetic Resonance Imaging Images: A Pilot Study.

Nowadays, magnetic resonance imaging (MRI) has a high ability to distinguish between soft tissues because of high spatial resolution. Image processing is extensively used to extract clinical data from imaging modalities. In the medical image processing field, the knee's cyst (especially Baker) segmentation is one of the novel research areas. There are different methods for image segmentation. In this paper, the mathematical operation of the watershed algorithm is utilized by MATLAB software based on marker-controlled watershed segmentation for the detection of Baker's cyst in the knee's joint MRI sagittal and axial T2-weighted images. The performance of this algorithm was investigated, and the results showed that in a short time Baker's cyst can be clearly extracted from original images in axial and sagittal planes. The marker-controlled watershed segmentation was able to detect Baker's cyst reliable and can save time and current cost, especially in the absence of specialists it can help us for the easier diagnosis of MRI pathologies.

Analysis of the paraspinal muscle morphology of the lumbar spine using a convolutional neural network (CNN)

PurposeThis single-center study aimed to develop a convolutional neural network to segment multiple consecutive axial magnetic resonance imaging (MRI) slices of the lumbar spinal muscles of patients with lower back pain and automatically classify fatty muscle degeneration.MethodsWe developed a fully connected deep convolutional neural network (CNN) with a pre-trained U-Net model trained on a dataset of 3,650 axial T2-weighted MRI images from 100 patients with lower back pain. We included all qualities of MRI; the exclusion criteria were fractures, tumors, infection, or spine implants. The training was performed using k-fold cross-validation (k = 10), and performance was evaluated using the dice similarity coefficient (DSC) and cross-sectional area error (CSA error). For clinical correlation, we used a simplified Goutallier classification (SGC) system with three classes.ResultsThe mean DSC was high for overall muscle (0.91) and muscle tissue segmentation (0.83) but showed deficiencies in fatty tissue segmentation (0.51). The CSA error was small for the overall muscle area of 8.42%, and fatty tissue segmentation showed a high mean CSA error of 40.74%. The SGC classification was correctly predicted in 75% of the patients.ConclusionOur fully connected CNN segmented overall muscle and muscle tissue with high precision and recall, as well as good DSC values. The mean predicted SGC values of all available patient axial slices showed promising results. With an overall Error of 25%, further development is needed for clinical implementation. Larger datasets and training of other model architectures are required to segment fatty tissue more accurately.

The Danger Zone for Iatrogenic Neurovascular Injury in All-Inside Lateral Meniscal Repair in Relation to the Popliteal Tendon: An MRI Study.

Background:Lateral meniscal repair can endanger the nearby neurovascular structure (peroneal nerve or popliteal artery). To our knowledge, there have been no studies to evaluate the danger zone of all-inside meniscal repair through the anteromedial (AM) and anterolateral (AL) portals in relation to the medial and lateral edges of the popliteal tendon (PT).Purpose:To establish the risk of neurovascular injury and the danger zone in repairing the lateral meniscus in relation to the medial and lateral edges of the PT.Study Design:Descriptive laboratory study.Methods:Using axial magnetic resonance imaging (MRI) studies at the level of the lateral meniscus, lines were drawn to simulate a straight, all-inside meniscal repair device, drawn from the AM and AL portals to both the medial and lateral edges of the PT. In cases in which the line passed through the neurovascular structure, a risk of iatrogenic neurovascular injury was deemed, and measurements were made to determine the danger zones of neurovascular injury in relation to the medial or lateral edges of the PT.Results:Axial MRI images of 240 adult patients were reviewed retrospectively. Repairing the body of the lateral meniscus through the AM portal had a greater risk of neurovascular injury than repairs made through the AL portal in relation to the medial edge of the PT (P = .006). The danger zone in repairing the lateral meniscus through the AM portal extended 1.82 ± 1.68 mm laterally from the lateral edge of the PT and 3.13 ± 2.45 mm medially from the medial edge of the PT. Through the AL portal, the danger zone extended 2.81 ± 1.94 mm laterally from the lateral edge of the PT and 1.39 ± 1.53 mm medially from the medial edge of the PT.Conclusion:Repairing the lateral meniscus through either the AM or the AL portals in relation to the PT can endanger the peroneal nerve or popliteal artery.Clinical Relevance:The surgeon can minimize the risk of iatrogenic neurovascular injury in lateral meniscal repair by avoiding using the all-inside meniscal device in the danger zone area as described in this study.

Axial-SpineGAN: simultaneous segmentation and diagnosis of multiple spinal structures on axial magnetic resonance imaging images

Providing a simultaneous segmentation and diagnosis of the spinal structures on axial magnetic resonance imaging (MRI) images has significant value for subsequent pathological analyses and clinical treatments. However, this task remains challenging, owing to the significant structural diversity, subtle differences between normal and abnormal structures, implicit borders, and insufficient training data. In this study, we propose an innovative network framework called ‘Axial-SpineGAN’ comprising a generator, discriminator, and diagnostor, aiming to address the above challenges, and to achieve simultaneous segmentation and disease diagnosis for discs, neural foramens, thecal sacs, and posterior arches on axial MRI images. The generator employs an enhancing feature fusion module to generate discriminative features, i.e. to address the challenges regarding the significant structural diversity and subtle differences between normal and abnormal structures. An enhancing border alignment module is employed to obtain an accurate pixel classification of the implicit borders. The discriminator employs an adversarial learning module to effectively strengthen the higher-order spatial consistency, and to avoid overfitting owing to insufficient training data. The diagnostor employs an automated diagnosis module to provide automated recognition of spinal diseases. Extensive experiments demonstrate that these modules have positive effects on improving the segmentation and diagnosis accuracies. Additionally, the results indicate that Axial-SpineGAN has the highest Dice similarity coefficient (94.9% ± 1.8%) in terms of the segmentation accuracy and highest accuracy rate (93.9% ± 2.6%) in terms of the diagnosis accuracy, thereby outperforming existing state-of-the-art methods. Therefore, our proposed Axial-SpineGAN is effective and potential as a clinical tool for providing an automated segmentation and disease diagnosis for multiple spinal structures on MRI images.

Is there a relationship between lower lumbar disc herniation and multifidus muscle volume in postmenopausal women?

Background/Aim: Lumbar disc herniation (LDH) is the most common cause of low back pain. It can also cause radiculopathy, sciatica, loss of sensation and motor loss due to pressure on the nerve roots. The multifidus muscle protects the lumbar axis. The aim of this study is to investigate the relationship between volumetric measurements and the degree of atrophy in the multifidus muscles with LDH in postmenopausal women. Methods: This case-control, retrospective study included 207 postmenopausal women with disc herniation on lumbar magnetic resonance imaging (MRI) and 183 reproductive period-premenopausal women with a mean age of 47.12 (10.07) years who were admittd to Adıyaman Training and Research Hospital between March 2020 and March 2021. LDH was detected at L4-L5 and L5-S1 levels on axial T2W lumbar MRI images. At these levels, the multifidus muscle volume was measured from the superior and inferior end plates of the vertebral bodies. The measurement of total volume was called multifidus total muscle volume (M-TMV), and the measurement made from the area without fat infiltration was called multifidus functional muscle volume (M-FMV). The M-TMV/FMV value was obtained to determine the degree of fat atrophy. Statistical analyses were performed, in which P

Антропометрические данные и площадь поперечного сечения сухожилий полусухожильной и нежной мышц по данным МРТ как предикторы диаметра графта для пластики передней крестообразной связки

Introduction Anterior cruciate ligament (ACL) reconstruction with quadrupled hamstring tendon autograft is a safe and reproducible surgery with good functional outcomes. Currently there is no consensus on capability of graft diameter planning. Objectives To investigate the influence of anthropometric data and cross-sectional area of semitendinosus (ST) and gracilis (GR) tendons according to preoperative magnetic resonance imaging (MRI) on intraoperative graft diameter. Material and methods The study included 111 consecutive patients (69 men and 42 women), who underwent ACL reconstruction with quadrupled hamstring autograft between 2015 to 2018. Height, weight and BMI were recorded in all patients preoperatively. Semitendinosus and gracilis tendons cross sectional areas (CSAst and CSAgr, respectively) were evaluated on preoperative MRI axial images. We also calculated doubled and quadrupled graft diameters (CSAst+gr and CSA4p, respectively) based on obtained MRI data. Collection of intraoperative data included length of each tendon separately, length and diameter of the resulting autograft. We used linear regression and Pearson correlation coefficient were used. The crosssectional areas were correlated to antropometric and intraoperative data. Using logistic regression, we determined the probability of obtaining a graft diameter of ≥ 7.5 mm. A critical level of statistical significance was set as 5 % (p ≤ 0.05). Results The median age accounted 37.4 ± 0.89 (13–58) years, height – 174.6 ± 0.84 (156–200) cm, weight – 78.5 ± 1.52 (45–120) kg, BMI – 25.6 ± 0.37 ( 18.49–41.5). Intraoperatively GR average length was 224.7 ± 3.06 (80–340) mm, ST – 256.3 ± 2.97 (160–340) mm, quadrupled graft – 111.3 ± 1.42 (80–140) mm. The most common graft diameter was 7 mm in females and 7.5 mm in males. We found strong positive correlation between graft diameter and CSA4p, СSAst+gr, CSAst, weight and height. Linear regression showed that graft diameter was influenced by CSA4p, СSAst+gr, CSAst and height. If CSA4p was ≥ 72 mm2, the probability of obtaining a graft of ≥ 7.5 mm at the time of surgery reached 90.6 %. Conclusion CSA4p may be used as a predictive characteristic for graft diameter preoperative planning. Our findings show that graft diameter was mainly influenced by height, СSAst+gr, CSAst and CSA4p.

Ultra-High Field Magnetic Resonance Imaging of the Retrobulbar Optic Nerve, Subarachnoid Space, and Optic Nerve Sheath in Emmetropic and Myopic Eyes.

PurposeWe aimed to image the optic nerve, subarachnoid space and optic nerve sheath in emmetropes and myopes ultra-high field (7-Tesla) magnetic resonance imaging (MRI). We targeted the retrobulbar distance of approximately 3 mm behind the eyeball, an area of clinical interest because of optic nerve sheath distensibility and pressure-related enlargement.MethodsEleven emmetropes (+0.75 to −0.50D, aged 20–41 years) and 10 myopes (−4.5 to −12D, aged 21–37 years) participated. Cross-sectional area of the optic nerve, subarachnoid space and optic nerve sheath at approximately 3 mm behind the eye were measured from two-dimensional T2-weighted coronal oblique MRI images obtained through the left optic nerve. Axial length of the left eye was measured from T2-weighted axial MRI images. In nine emmetropes and seven myopes, the optic nerve head was imaged with optical coherence tomography to compare retrobulbar and intraocular measures.ResultsRetrobulbar optic nerve, subarachnoid space and optic nerve sheath dimensions differed between myopes and emmetropes. Myopes tended to have smaller optic nerve and subarachnoid space. Longer MRI-derived axial length was associated with smaller optic nerve area (P = 0.03). Bruch's membrane opening area did not predict retrobulbar optic nerve area (P = 0.48).ConclusionsThis study demonstrates the feasibility of using 7-Tesla MRI to measure optic nerve, subarachnoid space, and optic nerve sheath dimensions behind the eye. In healthy adults, the retrobulbar optic nerve and subarachnoid space size are influenced by the degree of myopia.Translational Relevanceultra-high field MRI is a practical tool for assessing the morphometry of the optic nerve and surrounding anatomy behind the eye.

Volume quantification of endolymphatic hydrops in patients with vestibular schwannoma

ObjectiveThe origin of vestibular symptoms in patients with vestibular schwannoma (VS) is uncertain. We used intratympanic gadolinium-enhanced magnetic resonance imaging (MRI) to confirm the labyrinthine lesions in patients with VS and to explore the features of endolymphatic hydrops (EH) in these patients. MethodsIn total, 66 patients diagnosed with unilateral VS were enrolled in this study and underwent intratympanic gadolinium-enhanced MRI. The borders of the vestibule and endolymph were mapped on the axial MRI images, and the area and volume of vestibule and endolymph were automatically calculated using Osirix software, and the area and volume percentage of vestibular endolymph were obtained. ResultsThe area and volume percentages of vestibular endolymph on the affected side were significantly larger than those on the healthy side (both p < 0.001). Using Kendall's W test, we found that the area and volume percentages of vestibular endolymph on the affected side were consistent (p < 0.001), but the consistency was moderate (k = 0.574). The healthy side was also consistent (p < 0.001), and the degree of consistency was moderate (k = 0.444). We used 19.1% as the cut-off point to distinguish the presence or absence of vestibular EH; that is, the volume percentage of vestibular endolymph that was more than 19.1% were defined as the subgroup with hydrops, while the subgroup without hydrops included patients with a baseline level below 19.1%. No volume classification for vestibular EH was proposed. Based on this standard, 11/66 (16.7%) of the patients with VS in this study had vestibular EH. Conclusions.The volume percentage of the vestibular endolymph was more accurate than the area percentage for assessing vestibular EH. Using 19.1% as the cut-off point to distinguish the presence or absence of vestibular EH, we found that 16.7% of patients with VS had varying degrees of vestibular EH. We believe that the vestibular symptoms in patients with VS may originate from the peripheral lesions.

Magnetic resonance imaging and dynamic X-ray\u2019s correlations with dynamic electrophysiological findings in cervical spondylotic myelopathy: a retrospective cohort study

BackgroundDynamic somatosensory evoked potentials (DSSEP) can be used to disclose abnormalities of ascending sensory pathways at dynamic positions and diagnose cervical spondylotic myelopathy (CSM). However, radiographic tests including magnetic resonance imaging (MRI) and dynamic X-ray are used much more widely in the management of CSM. Our study aims to clarify the correlations between several radiographic parameters and the DSSEP results, and further determine their reliability with clinical data.MethodsWe retrospectively enrolled 38 CSM patients with surgical intervention. DSSEP tests were performed before surgery. Amplitude ratios of DSSEP N13 and N20 waves at extension and flexion were calculated and recorded as N13_E, N20_E, N13_F, N20_F, respectively. Baseline severity was evaluated with the modified Japanese Orthopedic Association (mJOA) score and the Nurick grades. Prognosis was evaluated based on the 2-year recovery rate. Sagittal diameter and transverse areas of the cord and canal were measured and the the compressive ratios at the compressed site (Compression_Ratio), central (Central_Ratio), and 1/4-lateral points (1/4-Lateral_Compression_Ratio), and spinal cord/Canal Area Ratio were calculated. The intramedullary T2 hyperintensity patterns (Ax-CCM types) were also collected from MRI axial images. Dynamic X-rays were used to test for segmental instability of the cervical spine. The correlations between radiologic findings, DSSEP data, and clinical assessments were investigated.ResultsWe found that DSSEP N13_E and N13_F correlated with the Compression_Ratio, Central_Ratio, 1/4-Lateral_Compression_Ratio (Pearson, p < 0.05) and Ax-CCM types (ANOVA, p < 0.05) in MRI axial images and cervical segmental instability in dynamic X-ray (t-test, p < 0.05). Apart from the 1/4-Lateral_Compression_Ratio, these radiographic parameters above also correlated with the baseline clinical assessments (Spearman or ANOVA or t-test, p < 0.05) and postoperative recovery rate (Pearson or ANOVA or t-test, p < 0.05).ConclusionsWe found that the preoperative Compression_Ratio, Central_Ratio and 1/4-Lateral_Compression_Ratio in MRI and cervical segmental instability in dynamic X-ray could reflect the dynamic neural dysfunction of the spinal cord. Different Ax-CCM types corresponded to different DSSEP results at extension and flexion, suggesting divergent pathophysiology. These radiographic parameters could help evaluate disease severity and predict postoperative prognosis.

Quantification of body composition in renal cell carcinoma patients: Comparing computed tomography and magnetic resonance imaging measurements

PurposeBody composition measures provide valuable information for prognostication and treatment election in cancer patients. We investigated the novel use of magnetic resonance imaging (MRI) for skeletal muscle and adipose tissue cross-sectional area measurements in preoperative renal cell carcinoma (RCC) patients. Materials and methodsRCC patients with pre-operative CT and MRI abdominal imaging were identified. Semi-automatic segmentation measurement of skeletal muscle area (SMA), intramuscular fat area (IMFA), visceral fat area (VFA), subcutaneous fat area (SFA), linear measurements of psoas, paraspinal muscles were performed. Pearson correlation coefficients, Bland-Altman plot analyses were done. Multivariable regression analysis examined the relationship between patient characteristics and skeletal muscle. ResultsImage analysis was performed on 58 RCC patients with preoperative CT and MRI imaging. For segmentation measures, r = 0.99, 0.99, 0.99, and 0.98 for SMA, IMFA, VFA, SFA, respectively, and 0.96 for linear measures of skeletal muscle. Bland-Altman analysis revealed a bias toward larger CT value for SMA (1.35 %), linear muscle measures (2.79 %), and SFA (10.34 %), and toward larger MRI values for IMFA (0.75 %) and VFA (5.81 %). ECOG ≥ 1 was associated with lower skeletal muscle than ECOG 0 for all measurements. ConclusionsStrong correlation of CT and MRI cross sectional measurements of skeletal muscle and adipose tissues supports the use of axial MRI images for comprehensive measurement of body composition. This has widespread implications for body composition research and cancer patient care.

Variations in Glenohumeral Bony Morphology May Predict Recurrent Instability after Arthroscopic Bankart Repair

Objectives:Variations in bony anatomy may be associated with failure of stabilization surgery. The aim of this study was to develop a method to measure bony morphology on magnetic resonance imaging (MRI) to identify risk factors for failure after Bankart repair.Methods:This was a retrospective case-control study of 118 patients. Cases of postoperative dislocation were compared to matched controls. Demographic data was obtained by chart review and radiographic data from preoperative MRI. Volume was measured using a 3-D model. Radius of curvature of the humeral head and glenoid was measured on axial MRI images. Statistical analysis used student’s t-test for continuous variables and either Fisher’s exact or Chi-squared test for categorical variables; P value < 0.05 was significant. Interrater reliability between reviewers was calculated using interclass correlation coefficients (r).Results:Forty-six patients who had a postoperative dislocation met inclusion criteria and were matched to 72 controls. There was no difference between groups for demographic (age, sex, percentage of contact athletes) or radiographic (glenoid bone loss, off-track Hill-Sachs lesions) parameters. The average number of preoperative dislocations was higher in the case group (3.2 vs. 2.0, p=0.003). The humeral head (68.8 ml vs 62.8 ml, p=0.05) volume was greater in the case group, though this did not reach statistical significance. Glenoid volume (13.5 ml vs 12.8 ml, p=0.31) was similar between groups. The radius of curvature of the glenoid was larger, or shallower, in the case group compared to the control group (23.6 mm vs 22.6 mm, p=0.05), though the difference did not reach statistical significance. A greater percentage of patients with a glenoid radius of curvature > 24.5 mm experienced a postoperative dislocation compared to those who had a smaller radius of curvature (62.0% vs 29.8%, p < 0.01). In fact, patients who had glenoid radius of curvature > 24.5 mm were 5 times as likely to experience a postoperative dislocation compared to those who did not (odds ratio 5.04, 95% CI 2.13 – 11.94, p < 0.01) There was no significant difference between the number of preoperative dislocations between patients with larger or smaller glenoid radius of curvature (2.6 vs 2.3, p = 0.55). There was a strong interrater reliability for measurement of humeral head volume, glenoid volume, radius of curvature of glenoid and radius of curvature of humeral head (r = 0.94, 0.88, 0.89, 0.95).Conclusion:The results of this study demonstrate that a larger radius of curvature, indicative of a shallower glenoid, is associated with failure following primary arthroscopic Bankart. These findings suggest that the bony concavity of the glenoid may play a role in stability.Figure 1.

THE RELATIONSHIP BETWEEN PATELLAR MORPHOLOGY AND LATERAL PATELLAR INSTABILITY

Background: Lateral patellar instability (LPI) is a substantial cause of morbidity in the pediatric population. Previously identified risk factors for LPI include trochlear dysplasia, a lateralized tibial tubercle, genu valgum, femoral anteversion, and external tibial torsion. Less is known regarding the relationship between patellar morphology and LPI. Purpose: The goal of this study is to determine whether there exists a relationship between patellar morphology and LPI. Methods: Magnetic resonance imaging (MRI) evaluation was performed for patients under 18 years of age with LPI and compared to a control group of MRIs of patients with anterior cruciate ligament (ACL) rupture. Using T2 axial MRI images, the lateral and medial facet angle of both the bone and cartilage of the patella was measured at three locations: the most proximal and distal aspects of the patella where the cartilage of the facets could be identified and the widest point of the patella. The width of the patella at each point was also recorded, resulting in 15 total data points per subject (5 at each of the three locations on the patella). Results were analyzed and compared between the instability group and the control group to determine any relationship between facet angle and LPI. Results: 196 MRIs were reviewed, 97 in the instability group and 96 in the control group. The LPI group was noted to have a less steep angle at the proximal medial patellar facet of both the bone (LPI 27.2° ± 9.3° ; control 32.7° ± 8.8°, p &lt; 0.001) and cartilage (LPI 26.5° ± 8.8°, control 32.7° ± 8.4°, p &lt; 0.001) as well as a less steep angle of the cartilage at the distal lateral facet (LPI 23.4° ± 7.2°, control 25.6° ± 6.6°, p = 0.033). No other differences were noted for the remaining 12 data points. Conclusion: The are very few differences in patellar morphology between patients with and without LPI. Patients were LPI have a less steep angle of the bone of the proximal medial facet, the cartilage of the proximal medial facet, and the cartilage of the distal lateral facet when compared to a control group. [Figure: see text]

Diagnostic value of the axial view of magnetic resonance imaging to identify two-dimensional shapes of full-thickness rotator cuff tears.

Coronal and sagittal views of magnetic resonance imaging (MRI) were used to determine rotator cuff tear size and fatty infiltration, but these images were not enough to identify the tear shape. To correlate the preoperative axial MRI views and arthroscopic surgical findings to identify the two-dimensional shapes in rotator cuff tears. This study included 166 patients who underwent arthroscopic repair between 2015 and 2018. Preoperative coronal, sagittal, and axial MRI views were evaluated for tear size and geographic configuration in axial sections, and the length and the width were measured and were matched with arthroscopic surgical views by lateral portals. The agreement of axial MRI views with the arthroscopic view was 88.0% in crescent, 97.2% in longitudinal, 78.6% in massive, and 100% in rotator cuff tear arthropathy. The mean agreement rate of axial MRI views with arthroscopic view was 81.9%. Mean mediolateral and anteroposterior tear sizes on axial MRI were 16.68 mm and 19.33 mm, respectively. Mean mediolateral and anteroposterior tear sizes by arthroscopic view were 21.49 mm and 21.04 mm, respectively. Tear sizes by MRI axial images were 71.3% of arthroscopic view. SST/IST degenerative changes were noted in most patients with massive tears and rotator cuff arthropathy (P = 0.001). Rotator cuff tear shape on preoperative axial MRI view had close agreement (81.9%) with arthroscopic findings by lateral portal, and tear size by preoperative axial MRI views was 71.3% of that of arthroscopic view. Axial MRI views helped to predict the geometric tear shape of rotator cuff tears.

Assessment of Radiomics and Deep Learning for the Segmentation of Fetal and Maternal Anatomy in Magnetic Resonance Imaging and Ultrasound

Recent advances in fetal imaging open the door to enhanced detection of fetal disorders and computer-assisted surgical planning. However, precise segmentation of womb's tissues is challenging due to motion artifacts caused by fetal movements and maternal respiration during acquisition. This work aims to efficiently segment different intrauterine tissues in fetal magnetic resonance imaging (MRI) and 3D ultrasound (US). First, a large set of ninety-four radiomic features are extracted to characterize the mother uterus, placenta, umbilical cord, fetal lungs, and brain. The optimal features for each anatomy are identified using both K-best and Sequential Forward Feature Selection techniques. These features are then fed to a Support Vector Machine with instance balancing to accurately segment the intrauterine anatomies. To the best of our knowledge, this is the first time that "Radiomics" is expanded from classification tasks to segmentation purposes to deal with challenging fetal images. In addition, we evaluate several state-of-the-art deep learning-based segmentation approaches. Validation is extensively performed on a set of 60 axial MRI and 3D US images from pathological and clinical cases. Our results suggest that combining the selected 10 radiomic features per anatomy along with DeepLabV3+ or BiSeNet architectures for MRI, and PSPNet or Tiramisu for 3D US, can lead to the highest fetal / maternal tissue segmentation performance, robustness, informativeness, and heterogeneity. Therefore, this work opens new avenues for advancement of segmentation techniques and, in particular, for improved fetal surgical planning.

Primary appendicular soft-tissue sarcoma resection: What tumour parameters affect wound closure planning?

Wound closure after wide, local excision of an appendicular soft-tissue sarcoma (STS) can be challenging. This study evaluates the value of magnetic resonance imaging (MRI)-based tumour parameters in planning wound closure. A total of 71 patients with a primary limb-based STS, excluding vascular or osseous involvement, excluding the shoulder or hand and hip or foot were included. Axial MRI images were used to measure the circumferences and cross-sectional areas of the limb, bone, and tumour. The tumour diameter, length, and depth at the level of maximal tumour dimension were measured to identify the tumour's relative contribution to the planning of optimal wound closure management through primary closure (PC) or reconstructive surgery (RS). Eighteen patients required planned wound RS. Wound complications occurred in 14% overall. Tumours, which were closed by PC, were of significantly greater depth, shorter radial diameter, and shorter tumour circumference relative to those closed by RS. On multivariate analysis, tumour depth was the greatest contributory factor in predicting type of wound closure. A quantitative analysis of MRI-based tumour parameters demonstrates tumour depth as the most predictive factor in planning for the type of wound closure and may prove beneficial in providing greater insight into planned wound management of sarcoma resection.

Radiologic Assessment of Cervical Canal Stenosis Using Kang MRI Grading System: Do Clinical Symptoms Correlate with Imaging Findings?

IntroductionMagnetic resonance imaging (MRI) is widely used in the evaluation of cervical canal stenosis and spinal cord compression. Kang et al. formulated a new MRI grading system for assessing canal stenosis which takes cord signal change into account. The purpose of the study was to determine the agreement between Kang's grading system and neurological symptoms.Methods A cross-sectional study was conducted at Aga Khan University Hospital between April 2014 and December 2015. Patients meeting inclusion criteria were enrolled. T2 sagittal and T2 axial MRI images were acquired and reported by a consultant neuroradiologist, in accordance with the MRI grading system suggested by Kang et al. Neurologic clinical symptoms were acquired by the history taken by the principal investigator. More than one neurologic symptoms and Kang MRI grade 2 or 3 were taken as positive evidence of cord compression resulting from canal stenosis.ResultsAmongst 126 subjects, 54% were females. Mean age of patients was 50.3 ± 14.3 years (range 19-83 years). Average disease duration was 4.61 ± 3.73 (range 1-24 months). In the majority of the patients, the findings were found at the C5-C6 level. 65.1% of patients were identified positive for cervical canal stenosis by Kang grading system. Most common neurological symptoms were pain (99%) and numbness (56%). Cohen’s Kappa was run to evaluate the agreement between neurological symptoms and Kang grading system. There was a strong agreement between the two methods, K = 0.81 (95% CI 0.70-0.92), p < 0.001.ConclusionThere was a substantial agreement between Kang's grading system and the presence of clinical symptoms. The agreement was greatest in females, older patients, and those with longer duration of symptoms.

The role of the anterior talofibular ligament area as a morphological parameter of the chronic ankle sprain

BackgroundRepetitive microtrauma can result in a hypertrophied ATFL. Previous studies have found that the anterior talofibular ligament thickness (ATFLT) is correlated with lateral ankle sprains, ligament injuries and chronic stroke in patients, and thickened anterior talofibular ligament (ATFL) has been considered to be a major morphologic parameter of hypertrophied ATFL. However, hypertrophy is different from thickness. Thus, we devised the anterior talofibular ligament area (ATFLA) as a new morphological parameter to evaluate the hypertrophy of the whole ATFL. MethodsATFL samples were collected from 53 patients with sprain group and from 50 control subjects who underwent magnetic resonance imaging (MRI) of the ankle and revealed no evidence of lateral ankle injury. Axial T1-weighted MRI images were collected at the ankle level from all subjects. We measured the ATFLA and ATFLT at the anterior margin of the fibular malleolus to the talus bone on the MRI using a picture archiving and communications system. The ATFLA was measured as the whole cross-sectional ligament area of the ATFL that was most hypertrophied in the axial MR images. The ATFLT was measured as the thickest point between the lateral malleolus and the talus of the ankle. ResultsThe average ATFLA was 25.0 ± 6.0 mm2 in the control group and 47.1 ± 10.4 mm2 in the sprain group. The average ATFLT was 2.3 ± 0.6 mm in the control group and 3.8 ± 0.6 mm in the hypertrophied group. Patients in sprain group had significantly greater ATFLA (p < 0.001) and ATFLT (p < 0.001) than the control subjects. A Receiver Operator Characteristics curve analysis showed that the best cut-off point of the ATFLA was 34.8 mm2, with 94.3% sensitivity, 94.0% specificity, and an AUC of 0.97 (95% CI, 0.94–1.00). The optimal cut-off point of the ATFLT was 3.1 mm, with 86.8% sensitivity, 86.0% specificity, and AUC of 0.95 (95% CI, 0.92–0.99). ConclusionATFLA is a new morphological parameter for evaluating chronic ankle sprain, and may even be more sensitive than ATFLT.

PATELLAR HEIGHT: COMPARISON OF MEASUREMENT TECHNIQUES AND CORRELATION WITH OTHER PATHOANATOMIC MEASURES OF PATELLAR INSTABILITY

Background: Patellar instability (PI) is a potentially debilitating knee condition that occurs most commonly in children and adolescents. Patellar height (PH) in the form of patella alta has been historically described, along with several others, as an anatomic risk factor for PI. However, numerous methods for evaluating PH exist without an established gold standard. Several ratio measurements have been proposed and studied including the Caton-Deschamps (CD) ratio. This can be measured on radiographs or magnetic resonance imaging (MRI) and is widely used due to its reliability to quantify PH across all age groups. A more recent measurement, the patellotrochlear index (PTI) quantifies PH by measuring the amount of patellar and trochlear chondral overlap on a sagittal MRI image and is expressed as a percentage. The PTI has been compared to the CD ratio as well as other PH measurements on MRI and has been proposed as a more accurate representation of clinically meaningful PH. We hypothesized that the PTI would have better inter- and intra-rater reliability than the CD ratio measured on standard radiographs, that most patients with PI would not have patella alta as represented by the PTI, and that there would be no correlation between the PTI and CD ratio. Further, the effect of PH on other radiographic measurements involved in assessing PI has not been evaluated. Given the effect trochlear dysplasia (TD) has on other radiographic parameters, such as patellar tilt and the tibial tubercle to trochlear groove distance, we sought to evaluate the correlation between PTI and the lateral trochlear inclination (LTI) angle and lateral patellar inclination (LPI) angle in a cohort of children and adolescents with PI. We hypothesized that the PTI would have no correlation between LTI or LPI in this patient population. Methods: Patients aged 9 to 18 years treated for PI between January 2014 and August 2017 were identified. The CD ratio was measured on lateral radiographs and PTI was measured on sagittal MRIs (Figure 1). Based on a previous study, patella alta with regards to PTI was defined as &lt; 12.5%. A CD ratio &gt; 1.2 was defined as alta based on historic standards. The LTI and LPI were measured on axial MRI images using recently described techniques that have high or near-perfect reliability (LTI: Interrater ICC = 0.971, 95% CI: 0.88 – 0.97. LPI: Interrater ICC = 0.885, 95% CI: 0.77 – 0.95). All measurements were performed by two independent observers. For reliability analysis, a cohort of 30 patients were randomly selected. Measurements were performed for this cohort by three independent observers and re-performed after a minimum of two weeks. Inter- and intra-rater correlation coefficients were calculated from this subgroup, and regression analysis was performed on the entire cohort. Results: Sixty-five patients met inclusion criteria for this study. PTI measurements had less variability and near perfect agreement between observers (ICC=0.92, 95% CI: 0.83-0.96) and within observers (ICC=0.99, 95% CI: 0.97-0.99), while CD ratio measurements had moderate agreement between observers (ICC=0.62, 95% CI: 0.34-0.80) and high agreement within observers (ICC=0.82, 95% CI: 0.65-0.91). Only 3.1% of patients had a PTI &lt; 12.5% and were classified as patella alta. 62.5% of patients had patella alta based on the CD ratio. Regression analysis demonstrated a significant but very weak correlation between PTI and CD ratio (r = -0.30, beta = -0.004, p = 0.0156). In this study, 71% of patients had an LTI &lt;11°, classifying them as having TD (average LTI 4.2±11.9°). Additionally, 73% of patients had an LPI &gt;13.5° classifying them as having excessive patellar tilt (average LPI 19.6±9.4°). No significant correlations were found between PTI and LTI (r = -0.0.13, p = 0.914), PTI and LPI (r = -0.092, p = 0.47), CD ratio and LTI (r = 0.19, p=0.14) or CD ratio and LPI (r = 0.162, p = 0.1959). Conclusion: The PTI was found to be a more reproducible and reliable measure of patellar height than the radiographic measured CD ratio. Additionally, PTI categorized a much smaller proportion of patients as having patella alta versus the CD ratio. No significant correlation was found between PTI or the CD ratio and measures of patellar tilt and trochlear dysplasia despite the majority of patients in this study having both. These results suggest that renewed investigation into the role of patellar height in PI is warranted and further studies should be conducted to determine what is clinically significant patella alta. These results also support prior work suggesting that the PTI is a more clinically relevant measure of PH. The weak correlation between PTI and the CD ratio is in line with prior work and if CD and other ratios are to continue to be used in clinical practice, revisiting normative values is warranted. [Figure: see text]

Visualization of the supraorbital notch/foramen using magnetic resonance imaging

The supraorbital notch/foramen involving the segment of the supraorbital nerve (SON) and the supraorbital artery (SOA) has little been explored with magnetic resonance imaging (MRI). Therefore, we explored these structures using MRI. A total of 90 patients underwent thin-sliced contrast MRI. In addition, eight sides of the orbits were dissected in four cadaveric heads. Cadaver dissections showed that the SOA coursed consistently beneath and in close proximity to the SON and reached the supraorbital notch/foramen. On axial MRI images, the supraorbital notch/foramen was identified in 98% on the right side and in 99% on the left. The distance from the midline to the midpoint of the supraorbital notch/foramen and depth from the skin surface to the supraorbital foramen/exit were measured. The median distance was 22.6 ± 3.08 mm on the right side and 22.8 ± 3.07 mm on the left, whereas the depth was 7.7 ± 1.39 mm on the right and 7.7 ± 1.43 mm on the left. Eighty percent of the sagittal images showed well-developed diploic veins in the supraorbital rim. Of these, 8.3% had anastomotic channels with the subcutaneous veins through the anterior wall of the supraorbital rim, 11.8% through the inferior wall, and 9% through the SOF. The SON and SOA segments passing through the supraorbital exit can be reliably located using contrast MRI. The supraorbital rim may function as the intracranial to extracranial anastomotic channel.

MRI assessment of changes in adipose tissue parameters after bariatric surgery.

Bariatric surgery and other therapeutic options for obese patients are often evaluated by the loss of weight, reduction of comorbidities or improved quality of life. However, little is currently known about potential therapy-related changes in the adipose tissue of obese patients. The aim of this study was therefore to quantify fat fraction (FF) and T1 relaxation time by magnetic resonance imaging (MRI) after Roux-en-Y gastric bypass surgery and compare the resulting values with the preoperative ones. Corresponding MRI data were available from 23 patients (16 females and 7 males) that had undergone MRI before (M0) and one month after (M1) bariatric surgery. Patients were 22–59 years old (mean age 44.3 years) and their BMI ranged from 35.7–54.6 kg/m2 (mean BMI 44.6 kg/m2) at M0. Total visceral AT volumes (VVAT-T, in L) were measured by semi-automatic segmentation of axial MRI images acquired between diaphragm and femoral heads. MRI FF and T1 relaxation times were measured in well-defined regions of visceral (VAT) and subcutaneous (SAT) adipose tissue using two custom-made analysis tools. Average BMI values were 45.4 kg/m2 at time point M0 and 42.4 kg/m2 at M1. Corresponding VVAT-T values were 5.94 L and 5.33 L. Intraindividual differences in both BMI and VVAT-T were highly significant (p<0.001). Average relaxation times T1VAT were 303.7 ms at M0 and 316.9 ms at M1 (p<0.001). Corresponding T1SAT times were 283.2 ms and 280.7 ms (p = 0.137). Similarly, FFVAT differences (M0: 85.7%, M1: 83.4%) were significant (p <0.01) whereas FFSAT differences (M0: 86.1, M1: 85.9%) were not significant (p = 0.517). In conclusion, bariatric surgery is apparently not only related to a significant reduction in common parameters of adipose tissue distribution, here BMI and total visceral fat volume, but also significant changes in T1 relaxation time and fat fraction of visceral adipose tissue. Such quantitative MRI measures may potentially serve as independent biomarkers for longitudinal and cross-sectional measurements in obese patients.