Plagiocephaly, from the Greek ‘plagios’ (slanting) and ‘kephale’ (head), refers to a condition of an infant’s head deformation by forces acting upon a malleable cranium. Marked plagiocephaly causes ...distress and stigma towards the baby and their family and has knock-on effects with craniofacial abnormalities, visual-field defects and delay in motor skills, and may also cause developmental difficulties. Current treatment methods have multiple drawbacks. This small, illustrated case series presents a novel, cost-effective, practical first-line treatment using a horseshoe-shaped gel head ring to redistribute pressure, allowing uniform growth and reshaping. Our early experience suggests that this method represents an effective treatment option with promising results so far.
The Green-Ampt expression for determining field-saturated hydraulic conductivity (Kfs) and matric flux potential (phi(m)) from falling-head ring infiltrometer measurements produces a singularity when ...the standpipe cross-section divided by the ring cross-section (R) equals the change in porous medium water content (delta theta). As R = delta theta is clearly possible in wet, low-permeability materials, the objective of this study was to develop an alternative falling-head ring infiltrometer analysis that applies for 0 < R < + oo, including R = delta theta . This was accomplished by replacing the natural logarithm in the Green-Ampt analysis with a Taylor series expansion, which removes the (R - delta theta ) divisor from the analysis. The Taylor series form of the Green-Ampt expression collapses to a simple algebraic expression when R = delta theta. Combining this algebraic expression with a similar analysis developed for gravitationless infiltration provides an improved approximate relationship for estimating Kfs when standpipe drawdown is small and R < delta theta.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
5.
Integra Head Ring Assemblies
Biomedical Safety & Standards,
12/2012, Volume:
42, Issue:
21
Journal Article, Trade Publication Article
In 54 cases of stereotactic irradiation (STI) seen at our hospital from April 2000 to March 2001, we examined the deficit in top-of-the-head computed tomography (CT) images and the influence that ...this deficit had on calculation of the STI dose. Results showed a slice deficit of more than 5 mm in 16 of the 54 cases and a maximum deficit of 25 mm. In most cases, the Gill-Thomas-Cosman (GTC) frame was used. The error in total dose monitor unit(DMU)calculation can be ignored if the top-of-the-head CT image deficit is less than 10 mm. If the deficit is more than 20 mm, it is possible that the total DMU calculation error will exceed 2%. In cases in which the deficit was greater than 30 mm, the average calculation error was 2.00%, and, in one case, the error was more than 7%. The GTC frame tends to produce CT image deficits in top-of-the-head images, whereas such images do not suffer this loss when a Brown-Roberts-Wells(BRW) head ring is used. When the CT image deficit is large, it is necessary to reduce the ratio of the arc that passes the area of the CT image deficit and to decrease the dose weight of the arc.
Building a Radiosurgery Program Litofsky, N. Scott; D’Agostino-Demers, Andrea
Principles and Practice of Stereotactic Radiosurgery
Book Chapter
One of the major trends in medicine over the past decade is the development of minimally invasive techniques for performance of surgical procedures. Patients desire these types of treatments because ...they are usually associated with less pain and quicker recovery. Insurance companies like these procedures because they are usually associated with short lengths of hospital stay and therefore less cost. Key issues that have had to be established include the development of the needed technologies, identification of appropriate patient profiles and disease processes that lend themselves to these treatments, and education of physicians—both those that treat the disease processes and those who refer patients for such treatments—about the procedures.
A simple head rest that can be mounted on an operating room trolley and facilitates fixation of the BRW stereotactic head ring in the anaesthetized or semiconscious patients is described.
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