Resolvins and inflammatory pain

Resolvins are a group of molecules derived from omega-3 fatty acids. They are part of a biochemical program that allows inflamed tissues to return to homeostasis once the need for the inflammatory response is over. Resolvins act in very low dose ranges in vitro and in vivo. New data suggest that they might have the potential to become very potent analgesic drugs in inflammatory pain

Neural Deformable Cone Beam CT

In oral and maxillofacial cone beam computed tomography (CBCT), patient motion is frequently observed and, if not accounted for, can severely affect the usability of the acquired images. We propose a highly flexible, data driven motion correction and reconstruction method which combines neural inverse rendering in a CBCT setting with a neural deformation field. We jointly optimize a lightweight coordinate based representation of the 3D volume together with a deformation network. This allows our method to generate high quality results while accurately representing occurring patient movements, such as head movements, separate jaw movements or swallowing. We evaluate our method in synthetic and clinical scenarios and are able to produce artefact-free reconstructions even in the presence of severe motion. While our approach is primarily developed for maxillofacial applications, we do not restrict the deformation field to certain kinds of motion. We demonstrate its flexibility by applying it to other scenarios, such as 4D lung scans or industrial tomography settings, achieving state-of-the art results within minutes with only minimal adjustments

Analyzing marker substances for Complex Regional Pain Syndrome (CRPS)

Weniger als 5% der Patienten entwickeln Komplex-Regionales Schmerzsyndrom (CRPS) nach einem Trauma, insbesondere nach Frakturen. Es ist ein schmerzhaftes Syndrom, dass durch eine Vielzahl von klinischen Merkmalen gekennzeichnet ist. Es kann chronisch werden, wenn es nicht in den ersten Monaten kuriert wird. Wahrscheinlich spielen mehrere pathophysiologische Mechanismen eine Rolle in CRPS. Es wird vermutet, dass Neuropeptide und anti-inflammatorische Lipid-Mediatoren involviert sind. In dieser Arbeit wurden diese Moleküle in Hautbiopsien und Serum mit dem Ziel der Korrelation ihrer Konzentration mit klinischen Parametern mittels Massenspektrometrie (MS) untersucht. Hochauflösende und insbesondere NanoMS identifizierte Peptide und Fettsäuren im niederen fmol-Bereich. Die Methodik zeigte aber auch wenig Toleranz gegenüber dem chemischen Untergrund, so dass vornehmlich die robustere Kapillarchromatography eingesetzt wurde. Die Serum-Proteaseaktivität mit einem Fokus auf Angiotensin-konvertierendem Enzym (ACE) wurde untersucht. Bradykinin (BK) wurde zügig zu BK1-8 und BK1-5 abgebaut. Niedrigere BK1-5 Levels waren in Übereinstimmung mit der Hypothese verringerter ACE-Aktivität in CRPS.Less than 5% of patients develop Complex Regional Pain Syndrome (CRPS) after trauma, mostly after fractures. It is a painful syndrome characterized by a variety of clinical features including classical signs of inflammation and it can become chronical if not cured in the first few months. Likely, a number of pathophysiological mechanisms play a role in CRPS. The involvement of neuropeptides and anti-inflammatory lipid mediators has been suggested. Here, mass spectrometry (MS) was used to investigate these molecules in skin biopsies and serum with the aim of correlating their concentration with clinical parameters. High-end and in particular nanoscale MS identified peptides as well as fatty acids at the low fmol level. However, it also showed little tolerance for the chemical background so that a more robust capillary chromatography approach was preferentially used. Serum protease activity with a focus on angiotensin converting enzyme (ACE) was studied. Bradykinin (BK) was rapidly degraded to BK1-8 and BK1-5. The formation of lower BK1-5 levels was indicated in agreement with the hypothesis of reduced ACE-activity in CRPS

Motion Correction for Separate Mandibular and Cranial Movements in Cone Beam CT Reconstructions.

BACKGROUND Patient motions are a repeatedly reported phenomenon in oral and maxillofacial cone beam CT scans, leading to reconstructions of limited usability. In certain cases, independent movements of the mandible induce unpredictable motion patterns. Previous motion correction methods are not able to handle such complex cases of patient movements. PURPOSE Our goal was to design a combined motion estimation and motion correction approach for separate cranial and mandibular motions, solely based on the 2D projection images from a single scan. METHODS Our iterative three-step motion correction algorithm models the two articulated motions as independent rigid motions. First of all, we segment cranium and mandible in the projection images using a deep neural network. Next, we compute a 3D reconstruction with the poses of the object's trajectories fixed. Third, we improve all poses by minimizing the projection error while keeping the reconstruction fixed. Step two and three are repeated alternately. RESULTS We find that our marker-free approach delivers reconstructions of up to 85% higher quality, with respect to the projection error, and can improve on already existing techniques, which model only a single rigid motion. We show results of both synthetic and real data created in different scenarios. The reconstruction of motion parameters in a real environment was evaluated on acquisitions of a skull mounted on a hexapod, creating a realistic, easily reproducible motion profile. CONCLUSIONS The proposed algorithm consistently enhances the visual quality of motion impaired CBCT scans, thus eliminating the need for a re-scan in certain cases, considerably lowering radiation dosage for the patient. It can flexibly be used with differently sized regions of interest and is even applicable to local tomography. This article is protected by copyright. All rights reserved

Local anaesthetic sympathetic blockade for complex regional pain syndrome

Local anaesthetic sympathetic blockade (LASB) is a common treatment for complex regional pain syndrome (CRPS). It involves blocking the activity of sympathetic nerves in the spine through the injection of a local anaesthetic drug. This updated review sought to identify the available evidence regarding whether LASB is effective at reducing pain in CRPS, how long any pain relief might last, and whether LASB is safe. We found a small number of small trials, all of which may be at risk of bias. We did not find evidence that LASB was better than placebo in reducing pain, or that it provided additional pain relief when added to rehabilitation. While a number of small studies compared LASB to other treatments, most did not find that LASB was better than any other intervention. Only five studies reported on adverse events. These studies reported only minor side effects but since most studies did not report this information we can draw no firm conclusions about the safety of LASB. Overall, while the evidence is very limited and precludes the drawing of strong conclusions, the existing evidence does not provide support for the efficacy of LASB in managing people with CRPS

Patterns of Sympathetic Responses Induced by Different Stress Tasks

Stress tasks are used to induce sympathetic nervous system (SNS) arousal. However, the efficacy and the patterns of SNS activation have not been systematically compared between different tasks

Cost-driven framework for progressive compression of textured meshes

International audienceRecent advances in digitization of geometry and radiometry generate in routine massive amounts of surface meshes with texture or color attributes. This large amount of data can be compressed using a progressive approach which provides at decoding low complexity levels of details (LoDs) that are continuously refined until retrieving the original model. The goal of such a progressive mesh compression algorithm is to improve the overall quality of the transmission for the user, by optimizing the rate-distortion trade-off. In this paper, we introduce a novel meaningful measure for the cost of a progressive transmission of a textured mesh by observing that the rate-distortion curve is in fact a staircase, which enables an effective comparison and optimization of progressive transmissions in the first place. We contribute a novel generic framework which utilizes the cost function to encode triangle surface meshes via multiplexing several geometry reduction steps (mesh decimation via half-edge or full-edge collapse operators, xyz quantization reduction and uv quantization reduction). This framework can also deal with textures by multiplexing an additional texture reduction step. We also design a texture atlas that enables us to preserve texture seams during decimation while not impairing the quality of resulting LODs. For encoding the inverse mesh decimation steps we further contribute a significant improvement over the state-of-the-art in terms of rate-distortion performance and yields a compression-rate of 22:1, on average. Finally, we propose a unique single-rate alternative solution using a selection scheme of a subset among LODs, optimized for our cost function, and provided with our atlas that enables interleaved progressive texture refinements

Standards for the diagnosis and management of Complex Regional Pain Syndrome: Results of a European Pain Federation task force

Background: Complex Regional Pain Syndrome is a painful and disabling post-traumatic primary pain disorder. Acute and chronic CRPS are major clinical challenges. In Europe progress is hampered by significant heterogeneity in clinical practice. We sought to establish standards for the diagnosis and management of CPRS. Methods: The European Pain Federation established a pan-European task force of experts in CRPS who followed a four-stage consensus challenge process to produce mandatory quality standards worded as grammatically imperative (must-do) statements. Results: We developed 17 standards in 8 areas of care. There are 2 standards in diagnosis, 1 in multi-disciplinary care, 1 on assessment, 3 for care pathways, 1 on information and education, 4 in pain management, 3 in physical rehabilitation, and 2 on distress management. The standards are presented, summarised, and their generation and consequences discussed. Also presented are domains of practice for which no agreement on a standard could be reached. Areas of research needed to improve the validity and uptake of these standards are discussed. Conclusion: The European Pain Federation task force present 17 standards of the diagnosis and management of CPRS for use in Europe. These are considered achievable for most countries, and aspirational for a minority of countries depending on their healthcare resource and structures.Significance: This position statement summarizes expert opinion on acceptable standards for CRPS care in Europe

Neuropathic pain:an updated grading system for research and clinical practice

The redefinition of neuropathic pain as "pain arising as a direct consequence of a lesion or disease affecting the somatosensory system," which was suggested by the International Association for the Study of Pain (IASP) Special Interest Group on Neuropathic Pain (NeuPSIG) in 2008, has been widely accepted. In contrast, the proposed grading system of possible, probable, and definite neuropathic pain from 2008 has been used to a lesser extent. Here, we report a citation analysis of the original NeuPSIG grading paper of 2008, followed by an analysis of its use by an expert panel and recommendations for an improved grading system. As of February, 2015, 608 eligible articles in Scopus cited the paper, 414 of which cited the neuropathic pain definition. Of 220 clinical studies citing the paper, 56 had used the grading system. The percentage using the grading system increased from 5% in 2009 to 30% in 2014. Obstacles to a wider use of the grading system were identified, including (1) questions about the relative significance of confirmatory tests, (2) the role of screening tools, and (3) uncertainties about what is considered a neuroanatomically plausible pain distribution. Here, we present a revised grading system with an adjusted order, better reflecting clinical practice, improvements in the specifications, and a word of caution that even the "definite" level of neuropathic pain does not always indicate causality. In addition, we add a table illustrating the area of pain and sensory abnormalities in common neuropathic pain conditions and propose areas for further research