Fast and accurate 3-D spine MRI segmentation using FastCleverSeg.

Accurate and efficient segmenting of vertebral bodies, muscles, and discs is crucial for analyzing various spinal diseases. However, traditional methods are either laborious and time-consuming (manual segmentation) or require extensive training data (fully automatic segmentation). FastCleverSeg, our proposed semi-automatic segmentation approach, addresses those limitations by significantly reducing user interaction while maintaining high accuracy. First, we reduce user interaction by requiring the manual annotation of only two or three slices. Next, we automatically Estimate the Annotation on Intermediary Slices (EANIS) using traditional computer vision/graphics concepts. Finally, our proposed method leverages improved voxel weight balancing to achieve fast and precise volumetric segmentation in the segmentation process. Experimental evaluations on our assembled diverse MRI databases comprising 179 patients (60 male, 119 female), demonstrate a remarkable 25 ms (30 ms standard deviation) processing time and a significant reduction in user interaction compared to existing approaches. Importantly, FastCleverSeg maintains or surpasses the segmentation quality of competing methods, achieving a Dice score of 94%. This invaluable tool empowers physicians to efficiently generate reliable ground truths, expediting the segmentation process and paving the way for future integration with deep learning approaches. In turn, this opens exciting possibilities for future fully automated spine segmentation.

A 3D Radiomics-Based Artificial Neural Network Model for Benign Versus Malignant Vertebral Compression Fracture Classification in MRI.

To train an artificial neural network model using 3D radiomic features to differentiate benign from malignant vertebral compression fractures (VCFs) on MRI. This retrospective study analyzed sagittal T1-weighted lumbar spine MRIs from 91 patients (average age of 64.24 ± 11.75 years) diagnosed with benign or malignant VCFs from 2010 to 2019, of them 47 (51.6%) had benign VCFs and 44 (48.4%) had malignant VCFs. The lumbar fractures were three-dimensionally segmented and had their radiomic features extracted and selected with the wrapper method. The training set consisted of 100 fractured vertebral bodies from 61 patients (average age of 63.2 ± 12.5 years), and the test set was comprised of 30 fractured vertebral bodies from 30 patients (average age of 66.4 ± 9.9 years). Classification was performed with the multilayer perceptron neural network with a back-propagation algorithm. To validate the model, the tenfold cross-validation technique and an independent test set (holdout) were used. The performance of the model was evaluated using the average with a 95% confidence interval for the ROC AUC, accuracy, sensitivity, and specificity (considering the threshold = 0.5). In the internal validation test, the best model reached a ROC AUC of 0.98, an accuracy of 95% (95/100), a sensitivity of 93.5% (43/46), and specificity of 96.3% (52/54). In the validation with independent test set, the model achieved a ROC AUC of 0.97, an accuracy of 93.3% (28/30), a sensitivity of 93.3% (14/15), and a specificity of 93.3% (14/15). The model proposed in this study using radiomic features could differentiate benign from malignant vertebral compression fractures with excellent performance and is promising as an aid to radiologists in the characterization of VCFs.

Randomised Controlled Trial of Fish Oil Supplementation on Responsiveness to Resistance Exercise Training in Sarcopenic Older Women.

This study aims to investigate the effects of fish oil supplementation on the muscle adaptive response to resistance exercise training, physical performance and serum levels of inflammatory cytokines in sarcopenic older women. A randomised, double-blind, placebo-controlled trial is performed with thirty-four sarcopenic women (2010 European Consensus of Sarcopenia), aged ≥ 65 years. The participants are allocated into the following two groups: Exercise and Fish Oil (EFO) and Exercise and Placebo (EP). Both groups undertook a resistance exercise programme over 14 weeks. All participants are instructed to ingest 4 g/day of food supplements; the EP group received sunflower oil capsules, and the EFO group, fish oil capsules. The cross-sectional area (CSA) of the quadriceps muscle is calculated using magnetic resonance imaging (MRI). The strength of the lower limbs is measured using isokinetic dynamometry. Both groups show improvements in CSA and strength after the intervention. Changes in EFO are significantly greater compared with EP for muscle strength (peak torque, 19.46 Nm and 5.74 Nm, respectively, p < 0.001). CSA increased after the intervention in both groups (EFO; 6.11% and EP; 2.91%), although there is no significant difference between the groups (p = 0.23). There are no significant intra-group, inter-group or time differences in any of the cytokines measured. The use of fish oil supplementation potentiates the neuromuscular response to the anabolic stimulus from training, increasing muscle strength and physical performance in sarcopenic older women.

Imaging Review of Normal and Abnormal Skeletal Maturation.

The growing skeleton undergoes well-described and predictable normal developmental changes, which may be misinterpreted a as pathologic condition at imaging. Primary and secondary ossification centers (SOCs), which form the diaphysis and the epiphysis of long bones, respectively, are formed by endochondral and intramembranous ossification processes. During skeletal maturation, the SOCs may appear irregular and fragmented, which should not be confused with fractures, osteochondritis dissecans, and osteochondrosis. These normal irregularities are generally symmetric with a smooth, round, and sclerotic appearance, which are aspects that help in the differentiation. The metaphysis, epiphysis, and growth plates or physes are common sites of injuries and normal variants in the pediatric skeleton. The metaphysis contains the newly formed bone from endochondral ossification and is highly vascularized. It is predisposed to easy spread of infections and bone tumors. The physis is the weakest structure of the immature skeleton. Injuries to this location may disrupt endochondral ossification and lead to growth disturbances. Pathologic conditions of the epiphyses may extend into the articular surface and lead to articular damage. At MRI, small and localized foci of bone marrow changes within the epiphysis and metaphysis are also a common finding. These can be related to residual red marrow (especially in the metaphysis of long bones and hindfoot), focal periphyseal edema (associated with the process of physeal closure), and ultimately to a normal ossification process. The authors review the imaging appearance of normal skeletal maturation and discuss common maturation disorders on the basis of developmental stage and location. ©RSNA, 2022.

Six-point DIXON and Magnetic Resonance Spectroscopy Techniques in Quantifying Bone Marrow Fat in Sickle Cell Disease.

RATIONALE AND OBJECTIVES: To compare bone marrow fat quantification using magnetic resonance spectroscopy (MRS) and six-point DIXON (6PD) techniques in patients with sickle cell disease (SCD) and healthy subjects. MATERIALS AND METHODS: Prospective study, with 43 SCD patients (24 homozygous [SS], 19 double heterozygous [SC), and 41 healthy subjects paired by age, weight and sex with SCD patients. All participants underwent magnetic resonance imaging with 6PD and single voxel MRS in the L3 vertebral body. Pearson's correlation, ROC curve, and bland-altman analysis were performed, p-values ​​≤0.05 were considered statistically significant for all tests. RESULTS: Significant linear correlation was found between fat fraction (FF) by 6PD and Total Lipids (TL) (r = 0.932; p < 0.001) and Saturated Lipids (SL) (r = 0.934; p < 0.001), in all subjects. Strong correlations were also identified considering subjects of the SS/SC subgroups. Despite high correlations, no significant difference was observed only between FF and SL in the SS subgroup (Bland-Altman analysis), indicating excellent agreement between the fat estimations in this specific situation. Significant differences were observed in all variables (FF, TL, SL) comparing the SCD and healthy subjects. The ROC curve between SCD and healthy subjects showed the following areas under the curve: FF(0.924) > TL(0.883) > SL(0.892). CONCLUSIONS: The comparison between fat quantification by the 6PD with MRS demonstrated an excellent correlation in SCD patients, especially in the SS subgroup, which usually has a higher degree of hemolysis. The diagnostic performance of 6PD and MRS is similar, with advantages of shorter imaging processing time and larger studied area with the 6PD.

Morphometric vertebral fracture risk in women with postsurgical hypoparathyroidism.

Introduction: Hypoparathyroidism (HP) is a rare endocrine disease and there are little data available on the risk of fragility fractures in these patients. PTH deficiency results in a positive bone balance with higher bone mass in all skeletal sites. However, whether these structural and dynamic skeletal changes have a negative impact on the fracture risk, it is not known. Methods: Aiming to investigate the risk of insufficiency vertebral fractures in HP, defined using morphometric criteria, a consecutive sampling of 44 women with chronic postsurgical HP was compared to a control group of 44 adult healthy women, matched by age with patients. Vertebral fractures were analyzed by the semiquantitative Genant's method followed by quantitative vertebral morphometry. Results: Morphometric vertebral fractures were identified in 5/44 (11.4%) patients and in 3/44 (6.8%) controls (p=0.731). Most fractures were classified as Genant II and III grades in HP patients, whereas most were Genant I in controls. A logistic regression multivariate analysis was conducted in which age, BMI and parathyroid status were the independent variables, and morphometric vertebral fracture was the dependent variable, but none of these factors was a significant predictor of fracture in this population (OR 1.01, 95% CI 0.96-1.07, p=0.634 for age; OR 2.24, 95%CI 0.47-10.50, p=0.306 for the presence/absence of HP and OR 0.92, 95% CI 0.76-1.10, p=0.369 for BMI). Conclusion: The results of this study cannot ensure a higher risk of fragility vertebral fractures in postsurgical HP patients. Instead, we only observed higher Genant grade classification of the deformed vertebrae in our sample.

Qualitative and quantitative magnetic resonance imaging evaluation of bone tissue vaso-occlusive events in patients with sickle cell disease.

OBJECTIVE: To evaluate the association between bone changes due to vaso-occlusive events in sickle cell disease (SCD) revealed by conventional MRI sequences and the fat fraction obtained using a 6-point DIXON technique (FFdix), in an attempt to use quantitative data as a biomarker for bone complications. METHODS: Cross-sectional study, with 48 SCD patients, 26-homozygous (HbSS), and 22-compound heterozygous (HbSC). Forty-eight healthy individuals paired by age, weight, and sex with SCD patients. All participants underwent lumbar spine and pelvis MRI. Conventional sequences: bone complications related to vaso-occlusive events-femoral head avascular necrosis, bone infarctions, "H"-shaped vertebrae, bone marrow necrosis. Six-point DIXON technique: quantitative evaluation of the bone marrow at pre-established sites (lumbar vertebrae, sacrum, iliacs, femoral heads, greater femoral trochanters, femoral necks). Pearson's correlation, ROC curve, and binary logistic regression analysis were performed. RESULTS: The most frequent findings in the SCD group included femoral head avascular necrosis (75%), bone infarctions (58.3%), "H"-shaped vertebrae (58.3%), and typical imaging findings of bone marrow necrosis (8.3%). Cortical bone thickness in the proximal femoral diaphysis in patients with SCD was moderately negatively correlated with FFdix in lumbar vertebrae, iliacs, femoral necks, and first sacral vertebrae. The ROC curves and odds ratios demonstrated excellent performance of FFdix in all the evaluated anatomical sites and identified patients having bone complications. CONCLUSIONS: FFdix could serve as a potential biomarker in SCD because of its association with bone complications secondary to vaso-occlusive events in patients with SCD, especially in femoral heads, femoral necks, and iliacs.

An international expert opinion statement on the utility of PET/MR for imaging of skeletal metastases.

BACKGROUND: MR is an important imaging modality for evaluating musculoskeletal malignancies owing to its high soft tissue contrast and its ability to acquire multiparametric information. PET provides quantitative molecular and physiologic information and is a critical tool in the diagnosis and staging of several malignancies. PET/MR, which can take advantage of its constituent modalities, is uniquely suited for evaluating skeletal metastases. We reviewed the current evidence of PET/MR in assessing for skeletal metastases and provided recommendations for its use. METHODS: We searched for the peer reviewed literature related to the usage of PET/MR in the settings of osseous metastases. In addition, expert opinions, practices, and protocols of major research institutions performing research on PET/MR of skeletal metastases were considered. RESULTS: Peer-reviewed published literature was included. Nuclear medicine and radiology experts, including those from 13 major PET/MR centers, shared the gained expertise on PET/MR use for evaluating skeletal metastases and contributed to a consensus expert opinion statement. [18F]-FDG and non [18F]-FDG PET/MR may provide key advantages over PET/CT in the evaluation for osseous metastases in several primary malignancies. CONCLUSION: PET/MR should be considered for staging of malignancies where there is a high likelihood of osseous metastatic disease based on the characteristics of the primary malignancy, hight clinical suspicious and in case, where the presence of osseous metastases will have an impact on patient management. Appropriate choice of tumor-specific radiopharmaceuticals, as well as stringent adherence to PET and MR protocols, should be employed.

Tissue Characterization by Low-Frequency Acoustic Waves Generated by a Single High-Frequency Focused Ultrasound Beam.

The mechanical properties of biological tissues are fingerprints of certain pathologic processes. Ultrasound systems have been used as a non-invasive technique to both induce kilohertz-frequency mechanical vibrations and detect waves resulting from interactions with biological structures. However, existing methodologies to produce kilohertz-frequency mechanical vibrations using ultrasound require the use of variable-frequency, dual-frequency and high-power systems. Here, we propose and demonstrate the use of bursts of megahertz- frequency acoustic radiation to observe kilohertz-frequency mechanical responses in biological tissues. Femoral bones were obtained from 10 healthy mice and 10 mice in which osteoporosis had been induced. The bones' porosity, trabecular number, trabecular spacing, connectivity and connectivity density were determined using micro-computed tomography (µCT). The samples were irradiated with short, focused acoustic radiation pulses (f = 3.1 MHz, t = 15 µs), and the low-frequency acoustic response (1-100 kHz) was acquired using a dedicated hydrophone. A strong correlation between the spectral maps of the acquired signals and the µCT data was found. In a subsequent evaluation, soft tissue stiffness measurements were performed with a gel wax-based tissue-mimicking phantom containing three spherical inclusions of the same type of gel but different densities and Young's moduli, yet with approximately the same echogenicity. Conventional B-mode ultrasound was unable to image the inclusions, while the novel technique proposed here showed good image contrast.

Multiangle Long-Axis Lateral Illumination Photoacoustic Imaging Using Linear Array Transducer.

Photoacoustic imaging (PAI) combines optical contrast with ultrasound spatial resolution and can be obtained up to a depth of a few centimeters. Hand-held PAI systems using linear array usually operate in reflection mode using a dark-field illumination scheme, where the optical fiber output is attached to both sides of the elevation plane (short-axis) of the transducer. More recently, bright-field strategies where the optical illumination is coaxial with acoustic detection have been proposed to overcome some limitations of the standard dark-field approach. In this paper, a novel multiangle long-axis lateral illumination is proposed. Monte Carlo simulations were conducted to evaluate light delivery for three different illumination schemes: bright-field, standard dark-field, and long-axis lateral illumination. Long-axis lateral illumination showed remarkable improvement in light delivery for targets with a width smaller than the transducer lateral dimension. A prototype was developed to experimentally demonstrate the feasibility of the proposed approach. In this device, the fiber bundle terminal ends are attached to both sides of the transducer's long-axis and the illumination angle of each fiber bundle can be independently controlled. The final PA image is obtained by the coherent sum of subframes acquired using different angles. The prototype was experimentally evaluated by taking images from a phantom, a mouse abdomen, forearm, and index finger of a volunteer. The system provided light delivery enhancement taking advantage of the geometry of the target, achieving sufficient signal-to-noise ratio at clinically relevant depths.

Semi-quantitative grading and extended semi-quantitative grading for osteoporotic vertebral deformity: a radiographic image database for education and calibration.

The Genant's semi-quantitative (GSQ) criteria is currently the most used approach in epidemiology studies and clinical trials for osteoporotic vertebral deformity (OVD) evaluation with radiograph. The qualitative diagnosis with radiological knowledge helps to minimize false positive readings. However, unless there is a face-to-face training with experienced readers, it can be difficult to apply GSQ criteria by only reading the text description of Genant et al. (in 1993), even for a musculoskeletal radiologist. We propose an expanded semi-quantitative (eSQ) OVD classification with the following features: (I) GSQ grade-0.5 is noted as minimal grade (eSQ grade-1) for OVDs with height loss <20%; (II) GSQ mild grade (grade-1) is the same as eSQ mild grade (grade-2); (III) GSQ moderate grade (grade-2) is subdivided into eSQ grade-3 (moderate, >25%-1/3 height loss) and eSQ grade-4 (moderately-severe, >1/3-40% height loss); (IV) GSQ severe grade is subdivided into eSQ grade-5 (severe, >40%-2/3 height loss) and eSQ grade-6 (collapsed, with >2/3 height loss). We advocate to estimate vertebral height loss with adjacent vertebral heights as the reference (rather than using individual vertebra's posterior height as the reference). This article presents radiographs of 36 cases with OVD, together with gradings using GSQ criteria and eSQ criteria. The examples in this article can serve as teaching material or calibration database for readers who will use GSQ criteria or eSQ criteria. Our approach for quantitative measurement is explained graphically.

Identification of the Artery of Adamkiewicz Using Multidetector Computed Tomography Angiography (MCTA).

Objective The aim of the present study is to evaluate the artery of Adamkiewicz by multidetector computed tomography angiography (MCTA) in a Brazilian population. Methods Two independent observers evaluated 86 coronary MCTA examinations. The variables studied included the identification of the artery of Adamkiewicz at its origin level, and its entry side in the spine. Results The artery of Adamkiewicz was detected in 71 (82.5%) examinations. The origin level was identified between the 9th and 11th thoracic vertebrae (T9 and T11) in 56 (79.2%) patients. In 65 (91.5%) patients, the artery was on the left side. The identification of the artery of Adamkiewicz using MCTA showed high reproducibility. Conclusions Our results were consistent with the literature regarding the identification of the artery of Adamkiewicz using MCTA, suggesting that this technique should be considered as an option to recognize this structure. In addition, we found that the distribution of the artery of Adamkiewicz in the Brazilian population is similar to that of other populations, that is, its most common origin is at the left side, between the 8th and 12th thoracic vertebrae (T8-T12).

Osteoporosis and Hepatic Steatosis: 2 Closely Related Complications in Short-Bowel Syndrome.

BACKGROUND: Osteoporosis has scarcely been prospectively investigated in short-bowel syndrome (SBS). This prospective study was designed to evaluate incretins, adipokines, bone mass, and lipid deposits from marrow adipose tissue (MAT), visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and liver (IHLs). METHODS: The study comprised 2 groups matched by gender, height, and age: the control group (CG) (9 males, 9 females) and the SBS group (SBSG) (6 males, 5 females). The SBSG was evaluated twice in an interval of 1 year (SBSG0 and SBSG1 ). The biochemical evaluation included incretins, leptin, and adiponectin. Dual-energy x-ray absorptiometry and magnetic resonance were, respectively, used to measure BMD and lipid deposits. RESULTS: Bone mineral density (BMD) was lower in the SBSG than in the CG, but there was no difference between SBSG0 and SBSG1 . There was no difference in MAT, SAT, and VAT, but IHL was lower in CG than in SBSG0 and SBSG1 . A negative correlation between MAT and third lumbar vertebrae BMD was found in the CG but not in SBSG0 or SBSG1 . There was a negative association between IHL and bone mass considering all participants (CG and SBSG0 ) (R2 = 0.38; P < .05). CONCLUSION: Appropriate nutrition assistance recovers body composition, reverts the relationship of bone mass and MAT, and mitigates bone loss in SBS. In spite of this, osteoporosis seems to be an early and persistent complication in SBS. Curiously, SBS seems to be a highly vulnerable condition for the development of hepatic steatosis and shows an association between bone mass and IHL.

Identification of the Artery of Adamkiewicz Using Multidetector Computed Tomography Angiography (MCTA) / Identificação da artéria de Adamkiewicz usando angiotomografia computadorizada por multidetectores (ATCM)

Abstract Objective The aim of the present study is to evaluate the artery of Adamkiewicz by multidetector computed tomography angiography (MCTA) in a Brazilian population. Methods Two independent observers evaluated 86 coronary MCTA examinations. The variables studied included the identification of the artery of Adamkiewicz at its origin level, and its entry side in the spine. Results The artery of Adamkiewicz was detected in 71 (82.5%) examinations. The origin level was identified between the 9th and 11th thoracic vertebrae (T9 and T11) in 56 (79.2%) patients. In 65 (91.5%) patients, the artery was on the left side. The identification of the artery of Adamkiewicz using MCTA showed high reproducibility. Conclusions Our results were consistent with the literature regarding the identification of the artery of Adamkiewicz using MCTA, suggesting that this technique should be considered as an option to recognize this structure. In addition, we found that the distribution of the artery of Adamkiewicz in the Brazilian population is similar to that of other populations, that is, its most common origin is at the left side, between the 8th and 12th thoracic vertebrae (T8-T12).

Resumo Objetivo Avaliar a artéria de Adamkiewicz por angiotomografia computadorizada por multidetectores (ATCM) em uma população brasileira. Métodos Dois observadores independentes avaliaram 86 exames de ACTM. As variáveis estudadas incluíram a identificação da artéria de Adamkiewicz no nível de origem e o lado de entrada da artéria na coluna vertebral. Resultados A artéria de Adamkiewicz foi identificada em 71 (82,5%) exames. O nível de origem foi identificado entre a 9a e a 11a vértebras torácicas (T9 e T11) em 56 (79,2%) pacientes. Em 65 (91,5%) pacientes, a artéria foi identificada no lado esquerdo. A identificação da artéria de Adamkiewicz usando ACTM mostrou elevada reprodutibilidade. Conclusões Obtivemos resultados consistentes com os da literatura prévia quanto à identificação da artéria de Adamkiewicz utilizando angiotomografia computadorizada por multidetectores. Nossos resultados sugerem que a ATCM pode ser considerada como uma opção para identificar a artéria de Adamkiewicz. Além disso, encontramos uma distribuição da artéria de Adamkiewicz na população brasileira semelhante à de outras populações, com a artéria de Adamkiewicz originando-se mais comumente no lado esquerdo, entre a 8a e a 12a vértebras torácicas (T8-T12).

Beyond the metabolic syndrome: Visceral and marrow adipose tissues impair bone quantity and quality in Cushing's disease.

The present study was designed to evaluate the relationship between bone traits [bone mineral density (BMD) and trabecular bone score (TBS)] and the accumulation of fat in adipose tissues [abdominal subcutaneous (SAT), visceral (VAT), marrow (MAT) and intrahepatic lipids (IHL)], as well as insulin resistance, in subjects with Cushing's disease (CD). The study included control (C = 27), paired (P = 16) and Cushing's disease (CD = 10) groups, which underwent biochemical assessment, dual X-ray absorptiometry, TBS, and magnetic resonance imaging to determine fat deposits. The CD group showed higher serum levels of glucose and insulin, as well as HOMA-IR values, but lower circulatory levels of osteocalcin, in comparison to C and P. The CD group exhibited lower L1-L4 BMD than P (P = 1.059 ± 0.141 vs CD = 0.935 ± 0.093 g/cm2, p < 0.05) (Fig 1A). The lumbar spine BMD from the C group was similar to the other groups. TBS was lower in CD than in P and C (C = 1.512±0.077 vs P = 1.405±0.150 vs CD = 1.135±0.136; p<0.05); there was also significant difference between C and P (p<0.05). MAT, VAT, and IHL were higher in CD than in C and P (p<0.05). Considering all subjects, there was a positive association between TBS with both lumbar spine BMD (R2 = 0.45; p<0.0001) and osteocalcin (R2 = 0.44; p = 0.05). TBS was negatively associated with MAT (R2 = 0.49; p = 0.01), VAT (R2 = 0.55; p<0.05), and HOMA-IR (R2 = 0.44; p<0.01). MAT was positively related with VAT (R2 = 0.44; p<0.01) and IHL (R2 = 0.41; p<0.05). In CD, insulin resistance and adipose tissue dysfunction, including high MAT, are active players in bone deterioration, as confirmed by lower lumbar spine BMD and lower TBS. Thus, our findings point to an additional component of the already well-known complex mechanisms of osteoporosis associated with hypercortisolism.