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Soft Tissue Structures (soft + tissue_structure)
Selected AbstractsImaging of cochlear tissue with a grating interferometer and hard X-raysMICROSCOPY RESEARCH AND TECHNIQUE, Issue 12 2009Claus-Peter Richter Abstract This article addresses an important current development in medical and biological imaging: the possibility of imaging soft tissue at resolutions in the micron range using hard X-rays. Challenging environments, including the cochlea, require the imaging of soft tissue structure surrounded by bone. We demonstrate that cochlear soft tissue structures can be imaged with hard X-ray phase contrast. Furthermore, we show that only a thin slice of the tissue is required to introduce a large phase shift. It is likely that the phase contrast image of the soft tissue structures is sufficient to image the structures even if surrounded by bone. For the present set of experiments, structures with low-absorption contrast have been visualized using in-line phase contrast imaging and a grating interferometer. The experiments have been performed at the Advanced Photon Source at Argonne National Laboratories, a third generation source of synchrotron radiation. The source provides highly coherent X-ray radiation with high-photon flux (>1012 photons/s) at high-photon energies (5,70 keV). Radiographic and light microscopy images of the gerbil cochlear slice samples were compared. It has been determined that a 20-,m thick tissue slice induces a phase shift between 1/3, and 2/3,. Microsc. Res. Tech., 2009. © 2009 Wiley-Liss, Inc. [source] A cranial intercondylar arthroscopic approach to the caudal medial femorotibial joint of the horseEQUINE VETERINARY JOURNAL, Issue 1 2009T. Muurlink Summary Reason for performing study: Current noninvasive techniques for imaging the soft tissue structures of the stifle have limitations. Arthroscopy is commonly used for the investigation and treatment of stifle pain. Cranial and caudal arthroscopic approaches to the femorotibial joints are used. However, complete examination of the axial aspect of the medial femorotibial joint (MFTJ) is not possible currently. Objective: To develop a cranial approach to the caudal pouch of the MFTJ and to assess whether it would allow a more complete examination of the compartment and facilitate the caudomedial approach. Method: The regional anatomy was reviewed and the technique developed on cadavers. A series of nonrecovery surgeries were performed to evaluate the procedure, which was then used in 7 clinical cases. Advantages compared to existing techniques and complications encountered were recorded. Results: Successful entry into the caudal pouch of the MFTJ was achieved in 20 of 22 cadaver legs, 8 of 8 joints of nonrecovery surgery horses and 6 of 7 clinical cases operated. The caudal ligament of the medial meniscus could be visualised, along with other axial structures of the caudal joint pouch. The technique was used to facilitate a caudomedial approach and allowed better triangulation within the joint space. Complications were minor and included puncture of the caudal joint capsule and scoring of the axial medial femoral condyle. Conclusions and potential relevance: It is possible to access the caudal pouch of the MFTJ arthroscopically using a cranial intercondylar approach. The technique has advantages when compared to existing techniques and is associated with few significant complications. A cranial approach to the caudal pouch of the MFTJ could complement existing techniques and be useful clinically. [source] Sequential Monitoring of Burials Containing Large Pig Cadavers Using Ground-Penetrating RadarJOURNAL OF FORENSIC SCIENCES, Issue 3 2006John J. Schultz Ph.D. ABSTRACT: Ground-penetrating radar (GPR) was used to monitor 12 pig burials in Florida, each of which contained a large pig cadaver. Six of the cadavers were buried in sand at a depth of 0.50,0.60 m, and the other six were buried at a depth of 1.00,1.10 m and were in contact with the upper surface of a clay horizon. Control excavations with no pig internment were also constructed as blank graves and monitored with GPR. The burials were monitored with GPR for durations of either 12,13 or 21,21.5 months when they were then excavated to correlate the decomposition state of the cadaver with the GPR imagery. Overall, cadavers in sand were easily detected for the duration of this study at 21.5 months, even when completely skeletonized. Conversely, in clay it became increasingly difficult to image the pig cadavers over the first year of burial, even when they still retained extensive soft tissue structures. [source] Joint compression alters the kinematics and loading patterns of the intact and capsule-transected AC jointJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2003Ryan S. Costic High compressive loads are transmitted through the shoulder across the acromioclavicular (AC) joint to the axial skeleton during activities of daily living and can lead to early joint degeneration or instability. The objective of this study was to quantify the effect of joint compression on the biomechanics of the intact and capsule-transected AC joint during application of three loading conditions. A robotic/universal force-moment sensor testing system was utilized to apply an anterior, posterior or superior load of 70 N in combination with 10 or 70 N of joint compression to fresh-frozen cadaveric shoulders (n = 12). The application of joint compression to the intact AC joint decreased the posterior translation in response to a posterior load (,6.6 ± 2.5 vs ,3.7 ± 1.0 mm, p<0.05). Joint compression also decreased the in situ force in the superior AC capsule by 10 N while increasing the joint contact force by 20 N for all loading conditions (p<0.05). The application of joint compression to the capsule-transected AC joint significantly decreased the amount of posterior and superior translation during posterior (,12.7 ± 6.1 vs ,5.5 ± 3.2 mm, p < 0.05) and superior (5.3 ± 2.9 vs 4.2 ± 2.3 mm, p < 0.05) loading, respectively, while significantly increasing the coupled translations (anterior,posterior, superior,inferior or proximal,distal) in all loading conditions (p < 0.05). The joint contact force also significantly increased by 20 N for all loading conditions (p < 0.05). This quantitative data suggests: (1) common surgical techniques such as distal clavicle resection, which initially reduce painful joint contact, may cause unusually high loads to be supported by the soft tissue structures at the AC joint; and (2) compressive loads transmitted across a capsule-transected AC joint could be concentrated over a smaller area due to the increased coupled motion and joint contact force. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Harvesting of intraoral autogenous block grafts from the chin and ramus region: Preliminary results with a variable square pulse Er:YAG laserLASERS IN SURGERY AND MEDICINE, Issue 5 2008Stefan Stübinger DDS Abstract Background and Objectives It was the aim of this pilot study to evaluate the feasibility, benefits and limitations of a variable square pulse (VSP) Er:YAG laser for harvesting intraoral bone grafts from either the chin or ramus region. Materials and Methods In 12 patients (5 female, 7 male) a VSP Er:YAG laser was used to harvest bone grafts either from the ramus (3) or the symphyseal area (9). For the osteotomies, the Er:YAG laser was applied with a pulse energy of 1,000 mJ, a pulse duration of 300 microseconds, and a frequency of 12 Hz (energy density 157 J/cm2). The spot size was 0.9 mm and the handpiece was kept at a distance of about 10 mm from the bone surface. Results There was no visible carbonization or osseous debris on the surface of the osteotomy gap. Damage of adjacent soft tissue structures by mechanical or thermal trauma was minimal. Cutting efficiency was excellent and the overall time required for the procedure was not increased. However, due to a free manual positioning of the laser beam in the non-contact mode, it was difficult to get a well defined osteotomy line without irregularities on the surface. Slight deviations of the original angulation of the laser beam led to considerable bone loss which restricted osteotomy of ramus grafts to three cases. Depth control was limited to visual inspection. Conclusion The bone ablation technique using a (VSP) Er:YAG laser yielded superior clinical results without impairment of wound healing and in comparison to other laser systems, no significant time loss occurred. Yet, the missing depth control and the necessity of carefully handling the laser beam position and its angulation limit the use of a (VSP) Er:YAG laser to regions where a safe and fixed guidance of the laser beam is feasible. Lesers Surg. Med. 40:312,318, 2008. © 2008 Wiley-Liss, Inc. [source] Imaging of cochlear tissue with a grating interferometer and hard X-raysMICROSCOPY RESEARCH AND TECHNIQUE, Issue 12 2009Claus-Peter Richter Abstract This article addresses an important current development in medical and biological imaging: the possibility of imaging soft tissue at resolutions in the micron range using hard X-rays. Challenging environments, including the cochlea, require the imaging of soft tissue structure surrounded by bone. We demonstrate that cochlear soft tissue structures can be imaged with hard X-ray phase contrast. Furthermore, we show that only a thin slice of the tissue is required to introduce a large phase shift. It is likely that the phase contrast image of the soft tissue structures is sufficient to image the structures even if surrounded by bone. For the present set of experiments, structures with low-absorption contrast have been visualized using in-line phase contrast imaging and a grating interferometer. The experiments have been performed at the Advanced Photon Source at Argonne National Laboratories, a third generation source of synchrotron radiation. The source provides highly coherent X-ray radiation with high-photon flux (>1012 photons/s) at high-photon energies (5,70 keV). Radiographic and light microscopy images of the gerbil cochlear slice samples were compared. It has been determined that a 20-,m thick tissue slice induces a phase shift between 1/3, and 2/3,. Microsc. Res. Tech., 2009. © 2009 Wiley-Liss, Inc. [source] | ||||||||||