Noninvasive Alternative (noninvasive + alternative)

Distribution by Scientific Domains

Selected Abstracts

Prevention of hemodialysis-related muscle cramps by intradialytic use of sequential compression devices: A report of four cases

Muhammad Ahsan
Background:, Hemodialysis (HD)-related lower extremity (LE) muscle cramps are a common cause of morbidity in end-stage renal disease patients on maintenance HD. Numerous pharmacologic and physical measures have been tried with variable success rates. Methods:, Sequential compression devices (SCD) improve venous return (VR) and are commonly used to prevent LE deep venous thrombosis in hospitals. We hypothesized that LE cramps are triggered by stagnant venous flow during HD and are preventable by improving VR. We prospectively studied four adult patients (mean age 61 14 years) on thrice-weekly HD who experienced two or more episodes of LE cramping weekly in the month before the study. SCD were applied before each HD on both legs and compressions were intermittently applied at 40 mmHg during treatment. Results:, All four patients reported complete resolution of cramping during the study period that lasted 1 month or 12 consecutive dialysis treatments. Conclusion:, Application of SCD to LE may prevent the generation of LE HD-related cramping in a select group of patients. Larger, controlled studies are needed to establish the utility of this noninvasive alternative for the prevention of LE HD-related cramps. [source]

Quantification of red myotomal muscle volume and geometry in the shortfin mako shark (Isurus oxyrinchus) and the salmon shark (Lamna ditropis) using T1 -weighted magnetic resonance imaging

Cameron N. Perry
Abstract T1 -weighted magnetic resonance imaging (MRI) in conjunction with image and segmentation analysis (i.e., the process of digitally partitioning tissues based on specified MR image characteristics) was evaluated as a noninvasive alternative for differentiating muscle fiber types and quantifying the amounts of slow, red aerobic muscle in the shortfin mako shark (Isurus oxyrinchus) and the salmon shark (Lamna ditropis). MRI-determinations of red muscle quantity and position made for the mid-body sections of three mako sharks (73.5,110 cm fork length, FL) are in close agreement (within the 95% confidence intervals) with data obtained for the same sections by the conventional dissection method involving serial cross-sectioning and volumetric analyses, and with previously reported findings for this species. The overall distribution of salmon shark red muscle as a function of body fork length was also found to be consistent with previously acquired serial dissection data for this species; however, MR imaging revealed an anterior shift in peak red muscle cross-sectional area corresponding to an increase in body mass. Moreover, MRI facilitated visualization of the intact and anatomically correct relationship of tendon linking the red muscle and the caudal peduncle. This study thus demonstrates that MRI is effective in acquiring high-resolution three-dimensional digital data with high contrast between different fish tissue types. Relative to serial dissection, MRI allows more precise quantification of the position, volume, and other details about the types of muscle within the fish myotome, while conserving specimen structural integrity. J. Morphol., 2007. 2007 Wiley-Liss, Inc. [source]

Diagnostic accuracy of a fibrosis serum panel (FIBROSpect II) compared with Knodell and Ishak liver biopsy scores in chronic hepatitis C patients

C. Christensen
Summary., Liver biopsy is the primary method of assessing liver injury in hepatitis C patients. FIBROSpect II (FS), a diagnostic panel of three extracellular matrix remodelling markers, may be useful as a noninvasive alternative to this procedure. The purpose of this study was to correlate FS results with liver fibrosis scores to determine if this test is sufficiently accurate to be a viable alternative to liver biopsy. A total of 142 serum specimens were evaluated for fibrosis with FS and were compared with Knodell and Ishak fibrosis scores. FS reports an index score ranging from 0.1 to 1.0, which corresponds to the probability of progressive liver fibrosis. Using a FS index cut-off of 0.42, 50 of 54 patients with Ishak 3,6 were classified as having advanced fibrosis (METAVIR F2,F4) and 58 of 88 patients with Ishak 0,2 as having no/mild fibrosis (METAVIR F0,F1), resulting in a sensitivity of 93%, specificity of 66%, and an overall test accuracy of 76%. With a 38% prevalence of advanced fibrosis, the negative predictive value was 94% and positive predictive value was 63%. A biopsy length of ,2 cm was associated with higher concordance between FS results and liver fibrosis scores (P = 0.01). FS was clinically useful in ruling out advanced fibrosis in hepatitis C by identifying patients with mild disease in whom treatment could be deferred. The limitation of this test is its decreased sensitivity and specificity in the middle of the test's reporting range between scores of 0.42 and 0.80. [source]

Magnetic resonance elastography: A review

Yogesh K. Mariappan
Abstract Magnetic resonance elastography (MRE) is a rapidly developing technology for quantitatively assessing the mechanical properties of tissue. The technology can be considered to be an imaging-based counterpart to palpation, commonly used by physicians to diagnose and characterize diseases. The success of palpation as a diagnostic method is based on the fact that the mechanical properties of tissues are often dramatically affected by the presence of disease processes, such as cancer, inflammation, and fibrosis. MRE obtains information about the stiffness of tissue by assessing the propagation of mechanical waves through the tissue with a special magnetic resonance imaging technique. The technique essentially involves three steps: (1) generating shear waves in the tissue, (2) acquiring MR images depicting the propagation of the induced shear waves, and (3) processing the images of the shear waves to generate quantitative maps of tissue stiffness, called elastograms. MRE is already being used clinically for the assessment of patients with chronic liver diseases and is emerging as a safe, reliable, and noninvasive alternative to liver biopsy for staging hepatic fibrosis. MRE is also being investigated for application to pathologies of other organs including the brain, breast, blood vessels, heart, kidneys, lungs, and skeletal muscle. The purpose of this review article is to introduce this technology to clinical anatomists and to summarize some of the current clinical applications that are being pursued. Clin. Anat. 23:497,511, 2010. 2010 Wiley-Liss, Inc. [source]