aortic knob

a·or·tic knob

the prominent shadow of the aortic arch on a frontal chest radiograph.
Farlex Partner Medical Dictionary © Farlex 2012
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Chest X-ray could not view the aortic knob or descending aorta well and could not rule out a right-sided aortic arch (Figure 1).
Caption: Figure 1: Portable X-ray which shows an absence of the aortic knob (arrow) and inability to visualize the descending aorta, suggestive of a right-sided aortic arch.
A chest radiograph ordered to evaluate for lung metastasis revealed cardiomegaly, a sclerotic aortic knob, and a mass-like abnormality of unknown etiology in the right paratracheal region (Fig.
This scoring system, which divided the extent of calcification in the aortic arch into four grades, was as follows: grade 0, no visible calcification; grade 1, small spots of calcification or single thin calcification of the aortic knob; grade 2, one or more areas of thick calcification, but [less than or equal to]50% of the circular area of the aortic knob; grade 3, circular calcification with >50% of circular area of the aortic knob.
The patient was assessed as having a typical case of laryngeal carcinoma, but a chest x-ray examination showed a mass located near the aortic knob. The patient was referred to the thoracic surgery department for further evaluation.
The chest X-ray examination revealed a cardio-thoracic index of 0.48, with calcification of aortic knob and normal lung aspect (Figure 2).
On the other hand there is paucity of data regarding the size of the aortic knob (AK) in Indian population which can be easily visualized in the Postero-Anterior Chest X-ray which is the commonest imaging modality in both rural and urban areas of India and economically feasible as it is cheaper than any other imaging modalities like CT scan or MRI, though the latter techniques are better indicators in assessing cardiac conditions than the chest X-ray.
The initial diagnostic test is on-table AP chest radiography (CXR), which may show a widening of the mediastinum, the most common finding (> 90% of cases), and blunting of the aortic knob, seen in 19.4% of cases.
We included a photo of a clavicle insertion in which the blade, held in a reverse grip, is plunged behind the opponent's collar bone, on the left side of the chest, and shoved down so that the blade ruptures the aortic knob. This is a part of the heart where the major vessels enter and exit and includes the vena cava and the aorta-- puncture those hosepipes and you've got maybe 30 seconds before you bleed out internally.
* CXR: Marked cardiomegaly in chronic AR with dilatation of the aortic knob. The cor bovinum of severe AR is the biggest and heaviest heart in cardiac pathology.
TEE was able to find aortic arch atheromatous disease in 55% of patients with a normal chest X-ray, and 91% of those who had heavily calcified aortic knobs [13].