Our ability to detect emphysema has changed dramatically in the early 1980s, when CT was used to demonstrate subtle
parenchymal patterns and objective measurement of lung density in units Haunsfild (HU) (BЂ "). Widespread implementation of high-resolution scanning put into the hands of each instrument to identify anatomical >> << emphysema until any clinical manifestations. BЂњEarlyBЂ "disease, not all diseases can be detected on CT, scattered
holes in the light of less than 5 mm is difficult or impossible to detect, but CT can detect the disease earlier than might >> << be detected by airway obstruction or changes in diffusion capacity (
). Sensitive method of sample volume, called sliding thin slab, minimum (or maximum, as first described above)
intensity projection was successfully tested for detection of minimal emphysema, but was not adopted widely, probably because << Difficulty >> additional steps and his inability to find much more than emphysema thin spiral scan because
from emphysema, simulating artifacts (
BЂ "). This requires a combination of thin slices of 3 - 8 mm pipe and choosing the minimum absorption of all the pieces to form an image in the stack in
. BЂњslidingBЂ "refers to the forming plate, adding one slice on top and remove one of >> << bottom and calculated density of the image. Qualitatively, with some thin slices, narrow window inhalation scan is best for detection and characteristics >> << emphysema. Representative idea of the disease can be obtained with three or four pieces of distance through the lungs. The volume
and weakening of blood vessels is well supported conclusions, but the accuracy of routine scanning is reduced if the picture
considered too dark or blurry motion. Respiratory motion makes it almost impossible to detect even moderate emphysema. The window width 800 HU and level with the center in B € '800 HU much better showing minimal emphysema than normal 1500 HU,
B € '500 HU settings. The degree of emphysema can be assessed subjectively by visual inspection. In every region of the lung, which appears
emphysematous estimated (
1) less than 25% of the area (
2) 26% to 50% region (
3) 51 % to 75% of the area, or (
4) 76% to 100% of the (,
). This four-point scale can be expanded to five levels, identifying (0) as usual. The region may be one or both lungs on
cut or dorsal and ventral parts of each lung. It was the regional distribution of emphysema, which were most useful in NETT for predicting outcome after lung volume reduction surgery >> << (LVRS), as suggested in previous reports (
). The overwhelming share of the top emphysema was found to predict a successful outcome NETT LVRS.
pieces in 20-mm intervals were considered sufficient for this determination. Emphysema distribution can be determined enough
using this subjective qualitative method, but changes such as the construction of emphysema from top to bottom, in
helped characterize the individual degree of emphysema heterogeneity (
). The severity of emphysema was rarely quantified. The scheme used two decades ago (
) on (0) no (
1) low-attenuation area less than 5 mm (
2) describes the low-attenuation area over 5 mm in addition to smaller or (
3) diffuse low attenuation without normal lung or large drainage area is very small damping. It was used to scan the entire lung
but was applied at the regional lung scan. The technology that was used to quantify emphysema many workers density mask technique that allows
light pixels in the selected range of HU (
, ). Pixels less than certain value (first B € '910 HU) can be identified, perhaps in color, and their number in comparison with the
total number of pixels in the image of lungs. Since the original description of all parameters that can be updated
relevance were the inspiration compared with the end of 1. 5 mm compared with 3 or 5 mm or 10 mm collimation and reconstruction >> << intravenous contrast medium in comparison with noncontrast and wide (1500BЂ "2000 HU) compared with a narrow (800BЂ" 1000 HU) windows version
or viewed on the console. Threshold measurement points emphysematous change from the bottom B € '900 HU below B € '960 HU on
different researchers with different thicknesses and cut algorithms reconstruction (
). This method can more accurately estimate the density of points than before. Quantitative evaluation of severity and
degree of emphysema was used to assess suitability for patients LVRS, follow the natural history of emphysema,
and look for wear reduction and treatment of N ±-1BЂ purchase lasix "antitrypsin (
). .
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