tentiran coas toraks
PENGENALAN X FOTO TORAK
X-RAYS and Contrast•Just as visual images require color differences to identify objects•X-rays require contrast differences to outline structure•X-ray absorption is proportional to density•It is the low density air content of the alveoli that outlines the normal and abnormal structure of the chest.
The Elements of a chest x-ray (CXR)
•The Broncho-vascular markings in the lung •The borders of the heart •The contours of the mediastinum and pleural space •The ribs and spine
This diagram shows the appearance of a bronchogram ( X-ray dye in the bronchi)and a schematic identifying the bronchial segments. Note that on the frontal view there is considerable overlap of segments.
This is the corresponding lateral view: Note that the segments that overlap on frontalview are separated clearly on lateral view, at the expense of overlapping structure fromright and left sides (which is not a problem on the frontal view). Since the frontal andlateral view resolve different segments, they are complimentary views allowinglocalization of problems in three dimensions.
Diaphragmatic and Mediastinal Contours
• The margins of the diaphragm and mediastinum are seen due to air-contrast from the adjacent lung. If the lung is consolidated (fluid filled) as in pneumonia, contrast is lost and the contour disappears.• The normal structures that account for the mediastinal contours seen on chest X-ray
Infiltrate in the lungs
• When fluid accumulates in lung, it may predominate in the alveolar (airspace) compartment or the interstitial compartment
• Typical bacterial pneumonia is an accumulation of exudative material in the alveolar spaces
• In addition to increasing the lung density, the infiltrate cancels the contrast between vessels and lung boundaries, and these structures disappear
• Air filled bronchi, normally invisible, will be contrasted by infiltrate creating air bronchograms.
Alveolar (Airspace) Consolidation
• The unit of alveolar consolidation is served by a single terminal bronchiole and represents a fluffy 3-5 mm nodule.
• In most alveolar consolidations, these fluffy alveolar nodules coalesce into dense consolidation.
• Communication between alveolar spaces mean that disease tends to spread freely until the pleura is reached. This results in the typical "lobar" distribution of pneumonia
• When alveolar infiltrate develops, air is replaced by fluid. Fluid does not create contrast with vessels and boundaries to the lung hence they are obscured
• The particular structure that is obscured indicates which portion of lung is involved. The disappearance of a normal lung border (ie. mediastinum or diaphragm) is called the silhouette sign. This is seen most often in pneumonia.
Differential Diagnosis of Alveolar Consolidation
• Bronchial obstruction by tumor or foreign body • Pulmonary hemorrhage • Severe pulmonary edema • Focal ARDS
Hyperinflation - Obstructive Airway disease
• Hyperinflation most commonly results from "flap-valve" air trapping in diseases like Asthma, Emphysema and Chronic Bronchitis
• Air trapping results in small increases in lung volume which are difficult to see on X-ray. Air trapping results in decreased minute ventilation and reflex vasoconstriction
Pneumotoraks• Definisi : terisinya rongga pleura oleh udara• Etiologi : * Spontan bula pecah * Didapat trauma• Bila terjadi mekanisme “flap valve”
pelebaran yang progresif rongga pleura akibatnya jantung dan saluran pernafasan (tension pneumotoraks)
EDEMA PARU• Definisi : ekstravasasi cairan dari vaskuler paru ke
dalam interstitial dan alveoar paru• Etiologi : 1. Imbalance Starling force - Peningkatan tekanan kapiler pulmonar - Penurunan tekanan plasma onkotik - Peningkatan tekanan negatif intertitial - Peningkatan permeabilitas kapiler 2. Kerusakan barier Alveoral- capiler 3. Obstruksi Limfatik 4. Idiopatik
Tahap Edema Paru :1. Fase awal2. Edema intertitial3. Edema alveolar
Bronkiektasis• Definisi : abnormal/ distorsi permanen dinding
bronkus/ saluran nafas seringnya karena infeksi sekunder
• Etiologi - Kongenital : bronkopulmonary sequstration, Williams-Campbell syndrom, Swyer-James syndrom, Mounier-Kuhn syndrom - Didapat infeksi kronis/ infeksi rekurent