الفهرس 
Anatomy of the Lung and Pulmonary VesselsOnly 14 pages are availabe for public view
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Abstract
There is a greater variability of the pulmonary venous drainage than previously appreciated, with greater variability of the right-sided venous drainage compared to the left –sided venous drainage.
There is significant variability in pulmonary vein ostial diameters, and distance to first bifurcation, with greatest variation in the ostial diameters of the superior pulmonary veins.
Inferior pulmonary vein ostial diameters in men were significantly larger than in women, but superior pulmonary vein and middle lobe vein ostial diameters were similar in men and women
The combination of MDCT and volume- rendering techniques post-processing provides higher-quality data sets and a method fully to harness the potential for image display and interpretation.
The PIOPED investigators recommend stratification of all patients suspected of having pulmonary embolism according to an objective probability assessment.
A negative D-dimer ELISA result with a low or moderate probability clinical assessment can safely exclude pulmonary embolism .
If pulmonary embolism is not excluded, CT angiography and venography is recommended by 77% of the PIOPED II investigators, although CT angiography alone in an option.
In patients with discordant findings at clinical assessment and CT imaging, further evaluation depends on clinical judgement.
Both pulmonary arterial and peripheral venous sides of venous thromboemblism(VTE) can now be efficiently and safely investigated by MDCT as the same time by combined CT angiography/CT venography protocols
In the emergency setting, the use of such a single test for patients suspected suffering from VTE on a clinical grounds may considerably shorten and simplify diagnostic algorithms..
Multiple data support the concept that single-slice and multi-slice-CT have fundamentally modified the diagnostic approach of patients with suspected PE.
It is clear that CT angiography has numerous advantages compared with other diagnostic tests.
Bearing in mind that an effective diagnostic strategy should be as flexible as possible to be applied in every clinical setting.
Pulmonary embolism is one of commonly encountered cardiovascular emergencies. Clinical features might suggest the diagnosis and imaging is required to confirm the diagnosis.
Chest radiography is usually normal in patients suffering from acute pulmonary embolism. In the past, pulmonary embolism is usually diagnosed by nuclear medicine imaging. There are intrinsic limi¬tations of the investigation. Radiopharmaceuticals might not be readily available. Patients might suffer from shortness of breath and compromising the image quality of ventilation scan. Evaluation of pulmonary artery by computed tomography is possible.
Patients with suspected pulmonary embolism usually receive 80-100ml iodinated contrast and the whole lung could be covered with one breath hold. The average acquisition time is 20 seconds and image might be compromised by motion artifact for those patients with severe shortness of breath.
Gadolinium-enhanced MR angiography is an excellent noninvasive technique for imaging the pulmonary arteries and is very accurate in depicting central, lobar, and segmental emboli, but at this stage, it is unreliable in depicting small subsegmental emboli.
Improvements in MR angiographic techniques will inevitably produce better results in the future. The ability to time the sequences so that images can be obtained during the peak of pulmonary arterial opacification is desirable.