Vertebral compression fracture is a deformity of vertebral bodies found on lateral spine images. To diagnose vertebral compression fracture, accurate measurement of vertebral compression ratio is ...required. Therefore, rapid and accurate segmentation of vertebra is important for measuring the vertebral compression ratio. In this study, we used 339 data of lateral thoracic and lumbar vertebra images for training and testing a deep learning model for segmentation. The result of segmentation by the model was compared with the manual measurement, which is performed by a specialist. As a result, the average sensitivity of the dataset was 0.937, specificity was 0.995, accuracy was 0.992, and dice similarity coefficient was 0.929, area under the curve of receiver operating characteristic curve was 0.987, and the precision recall curve was 0.916. The result of correlation analysis shows no statistical difference between the manually measured vertebral compression ratio and the vertebral compression ratio using the data segmented by the model in which the correlation coefficient was 0.929. In addition, the Bland–Altman plot shows good equivalence in which VCR values are in the area within average ± 1.96. In conclusion, vertebra segmentation based on deep learning is expected to be helpful for the measurement of vertebral compression ratio.
A huge amount of remote sensing data is acquired each day, which is transferred to image processing centers and/or to customers. Due to different limitations, compression has to be applied on-board ...and/or on-the-ground. This Special Issue collects 15 papers dealing with remote sensing data compression, introducing solutions for both lossless and lossy compression, analyzing the impact of compression on different processes, investigating the suitability of neural networks for compression, and researching on low complexity hardware and software approaches to deliver competitive coding performance.
Compressive myelopathy and compression fracture of aggressive vertebral hemangioma after parturition is a rare condition. Vertebral body compression fracture and high serum progesterone lead to ...extraosseous hemangioma enlargment cause narrowing the spinal canal which contribute to compressive myelopathy relate to pregnancy.
We report a case of compressive myelopathy and compression fracture of aggressive vertebral hemangioma after parturition in a 35-year-old woman. The patient complained unable to walk and experienced intense pain in the back.
Based on the clinical features and imaging studies, the patient underwent a T4-T6 laminectomy. Histopathology consistent with vertebral hemangioma.
The patient underwent laminectomy for decompression. After subperiosteal dissection of the paraspinal muscles and exposure of the laminae, there was no involvement of the lamina by the tumor. The epidural tumor was removed through the spaces lateral to the thecal sac. Vertebroplasty was performed through T5 pedicles bilaterally and 7 ml of polymethylmethacrylate (PMMA) cement was injected. T4-T6 pedicle screw fixation was performed for segmental fixation and fusion.
Six months after resection of the tumor the patient remained asymptomatic. She reported no low back pain and had returned to her normal daily activities, with no radiographic evidence of recurrence on MRI. Physical examination revealed that superficial and deep sensation was restored to normal levels in the lower extremities.
The occurrence of compressive myelopathy of pregnancy related vertebral hemangiomas is quite unusual. It can lead to serious neurologic deficits if not treated immediately. So, prompt diagnosis is important in planning optimal therapy and preventing morbidity for patients.
Compression for venous leg ulcers O'Meara, Susan; Cullum, Nicky; Nelson, E Andrea ...
Cochrane database of systematic reviews,
11/2012, Letnik:
11
Journal Article
Recenzirano
Odprti dostop
Up to one percent of people in industrialised countries will suffer from a leg ulcer at some time. The majority of these leg ulcers are due to problems in the veins, resulting in an accumulation of ...blood in the legs. Leg ulcers arising from venous problems are called venous (or varicose or stasis) ulcers. The main treatment is the application of a firm compression garment (bandage or stocking) in order to aid venous return. There is a large number of compression garments available and it was unclear whether they are effective in treating venous ulcers and, if so, which method of compression is the most effective.
To undertake a systematic review of all randomised controlled trials (RCTs) evaluating the effects on venous ulcer healing of compression bandages and stockings.Specific questions addressed by the review are:1. Does the application of compression bandages or stockings aid venous ulcer healing? 2. Which compression bandage or stocking system is the most effective?
For this second update we searched: the Cochrane Wounds Group Specialised Register (31 May 2012); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 5, 2012); Ovid MEDLINE (1950 to May Week 4 2012); Ovid MEDLINE (In-Process & Other Non-Indexed Citations 30 May 2012); Ovid EMBASE (1980 to 2012 Week 21); and EBSCO CINAHL (1982 to 30 May 2012). No date or language restrictions were applied.
RCTs recruiting people with venous leg ulceration that evaluated any type of compression bandage system or compression stockings were eligible for inclusion. Eligible comparators included no compression (e.g. primary dressing alone, non-compressive bandage) or an alternative type of compression. RCTs had to report an objective measure of ulcer healing in order to be included (primary outcome for the review). SECONDARY OUTCOMES of the review included ulcer recurrence, costs, quality of life, pain, adverse events and withdrawals. There was no restriction on date, language or publication status of RCTs.
Details of eligible studies were extracted and summarised using a data extraction table. Data extraction was performed by one review author and verified independently by a second review author.
Forty-eight RCTs reporting 59 comparisons were included (4321 participants in total). Most RCTs were small, and most were at unclear or high risk of bias. Duration of follow-up varied across RCTs. Risk ratio (RR) and other estimates are shown below where RCTs were pooled; otherwise findings refer to a single RCT.There was evidence from eight RCTs (unpooled) that healing outcomes (including time to healing) are better when patients receive compression compared with no compression.Single-component compression bandage systems are less effective than multi-component compression for complete healing at six months (one large RCT).A two-component system containing an elastic bandage healed more ulcers at one year than one without an elastic component (one small RCT).Three-component systems containing an elastic component healed more ulcers than those without elastic at three to four months (two RCTs pooled), RR 1.83 (95% CI 1.26 to 2.67), but another RCT showed no difference between groups at six months.An individual patient data meta-analysis of five RCTs suggested significantly faster healing with the four-layer bandage (4LB) than the short stretch bandage (SSB): median days to healing estimated at 90 and 99 respectively; hazard ratio 1.31 (95% CI 1.09 to 1.58).High-compression stockings are associated with better healing outcomes than SSB at two to four months: RR 1.62 (95% CI 1.26 to 2.10), estimate from four pooled RCTs.One RCT suggested better healing outcomes at 16 months with the addition of a tubular device plus single elastic bandage to a base system of gauze and crepe bandages when compared with two added elastic bandages. Another RCT had three arms; when one or two elastic bandages were added to a base three-component system that included an outer tubular layer, healing outcomes were better at six months for the two groups receiving elastic bandages.There is currently no evidence of a statistically significant difference for the following comparisons:⋅alternative single-component compression bandages (two RCTs, unpooled);⋅two-component bandages compared with the 4LB at three months (three RCTs pooled);⋅alternative versions of the 4LB for complete healing at times up to and including six months (three RCTs, unpooled);⋅4LB compared with paste bandage for complete healing at three months (two RCTs, pooled), six months or one year (one RCT for each time point);⋅adjustable compression boots compared with paste bandages for the outcome of change in ulcer area at three months (one small RCT);⋅adjustable compression boots compared with the 4LB with respect to complete healing at three months (one small RCT);⋅single-layer compression stocking compared with paste bandages for outcome of complete healing at four months (one small RCT) and 18 months (another small RCT);⋅low compression stocking compared with SSB for complete healing at three and six months (one small RCT);⋅compression stockings compared with a two-component bandage system and the 4LB for the outcome of complete healing at three months (one small, three-armed RCT); and,⋅tubular compression compared with SSB (one small RCT) for complete healing at three months.
4LB was more cost-effective than SSB. It was not possible to draw firm conclusions regarding other secondary outcomes including recurrence, adverse events and health-related quality of life.
Compression increases ulcer healing rates compared with no compression. Multi-component systems are more effective than single-component systems. Multi-component systems containing an elastic bandage appear to be more effective than those composed mainly of inelastic constituents. Two-component bandage systems appear to perform as well as the 4LB. Patients receiving the 4LB heal faster than those allocated the SSB. More patients heal on high-compression stocking systems than with the SSB. Further data are required before the difference between high-compression stockings and the 4LB can be established.
In recent years, the image and video coding technologies have advanced by leaps and bounds. However, due to the popularization of image and video acquisition devices, the growth rate of image and ...video data is far beyond the improvement of the compression ratio. In particular, it has been widely recognized that there are increasing challenges of pursuing further coding performance improvement within the traditional hybrid coding framework. Deep convolution neural network which makes the neural network resurge in recent years and has achieved great success in both artificial intelligent and signal processing fields, also provides a novel and promising solution for image and video compression. In this paper, we provide a systematic, comprehensive and up-to-date review of neural network-based image and video compression techniques. The evolution and development of neural network-based compression methodologies are introduced for images and video respectively. More specifically, the cutting-edge video coding techniques by leveraging deep learning and HEVC framework are presented and discussed, which promote the state-of-the-art video coding performance substantially. Moreover, the end-to-end image and video coding frameworks based on neural networks are also reviewed, revealing interesting explorations on next generation image and video coding frameworks/standards. The most significant research works on the image and video coding related topics using neural networks are highlighted, and future trends are also envisioned. In particular, the joint compression on semantic and visual information is tentatively explored to formulate high efficiency signal representation structure for both human vision and machine vision, which are the two dominant signal receptors in the age of artificial intelligence.
The mineral structure of soft clays is extremely fragile. Sampling operations and laboratory handling cause unavoidable disturbance. Undisturbed sampling is a theoretical concept because the stress ...release imposes disturbance. Consolidation tests on disturbed samples provide one-dimensional (1D)-compression curves very different from field response, which leads to inaccurate settlement estimates. Among the approaches for curve reconstruction, Schmertmann’s method is probably the most commonly adopted in engineering practice. However, it presents difficulties in determining preconsolidation stress. The paper primarily addresses Schmertmann’s and Nagaraj et al.’s propositions and discusses their advantages and shortcomings. A new approach for reconstructing the 1D-compression curve is proposed with the main objective being its independence of the interpretation of the experimental results. The validity was examined by comparing the reconstructed curves with those obtained by other methods. Experimental results on high- and low-quality specimens have been analyzed as well. The results revealed that the reconstructed curves for the cases analyzed are almost unique and independent of specimen quality. The proposed method allows both graphical and analytical implementation and the reconstructed curves are unaffected by experimental curve interpretation.
Achondroplasia is a genetic disorder known for short stature and skeletal abnormalities.
We present a case of narrowing of the foramen magnum from a large opisthion extending to the spinal canal.
...Foramen magnum stenosis and cervicomedullary stenosis are potentially life threatening neurological manifestations of achondroplasia.
Cross-sectional population-based observational study.
To estimate the prevalence of nonmyelopathic spondylotic cervical cord compression (NMSCCC) and cervical spondylotic myelopathy (CSM) in a ...population older than 40 years and to evaluate the magnetic resonance imaging (MRI) characteristics of these conditions.
The prevalence of neither NMSCCC nor CSM is known and there exists no commonly accepted quantitative MRI definition of cervical cord compression.
A group of 183 randomly recruited volunteers, 93 women, median age 66 years, range 40-80 years, underwent MRI examination of the cervical spine and spinal cord on a 1.5 T device using conventional sequences from disc levels C2/C3 to C6/C7. The imaging criterion for cervical cord compression was defined as a change in spinal cord contour at the level of an intervertebral disc on axial or sagittal MRI scan.
MRI signs of cervical cord compression were found in 108 individuals (59.0%; 95% CI: 51.5%-66.2%); their numbers increased with age from 31.6% in the fifth decade to 66.8% in the eighth. Clinical signs of symptomatic CSM were found in two cases (1.1%), and 75 cases (41.0%) were without compression. An anteroposterior cervical canal diameter at the level of intervertebral disc (CDdisc) of less than 9.9 mm was associated with the highest probability of NMSCCC-odds ratio (OR) = 32.5, followed by a compression ratio of ≤0.5: OR = 11.1.
The prevalence of NMSCCC in a population older than 40 years is higher than previously reported and increases with age. CDdisc and compression ratio had the highest capacity to discriminate between subjects with and without asymptomatic compression, and their cut-off values could be used to objectify criteria for cervical cord compression.
2.
By offloading intensive computation tasks to the edge cloud located at the cellular base stations, mobile-edge computation offloading (MECO) has been regarded as a promising means to accomplish the ...ambitious millisecond-scale end-to-end latency requirement of fifth-generation networks. In this paper, we investigate the latency-minimization problem in a multi-user time-division multiple access MECO system with joint communication and computation resource allocation. Three different computation models are studied, i.e., local compression, edge cloud compression, and partial compression offloading. First, closed-form expressions of optimal resource allocation and minimum system delay for both local and edge cloud compression models are derived. Then, for the partial compression offloading model, we formulate a piecewise optimization problem and prove that the optimal data segmentation strategy has a piecewise structure. Based on this result, an optimal joint communication and computation resource allocation algorithm is developed. To gain more insights, we also analyze a specific scenario where communication resource is adequate while computation resource is limited. In this special case, the closed-form solution of the piecewise optimization problem can be derived. Our proposed algorithms are finally verified by numerical results, which show that the novel partial compression offloading model can significantly reduce the end-to-end latency.
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