Back to Basics - 'Must Know' Classical Signs in Thoracic Radiology.

There are a few signs in radiology which are based on many common objects or patterns that we come across in our routine lives. The objective behind the association between such common objects and the corresponding pathologies is to make the reader understand and remember the disease process. These signs do not necessarily indicate a particular disease, but are usually suggestive of a group of similar pathologies which will facilitate in the narrowing down of the differential diagnosis. These signs can be seen in different imaging modalities like plain radiograph and computed tomography. In this essay, we describe 24 classical radiological signs used in chest imaging, which would be extremely helpful in routine clinical practice not only for radiologists but also for chest physicians and cardiothoracic surgeons.

Unilateral agenesis of internal carotid artery with intercavernous anastomosis: a rare case report.

Unilateral agenesis of internal carotid artery (ICA) with intercavernous anastomosis is a rare congenital anomaly. We present a case of a 25-year-old female with 2-month history of holocranial headache. Neurological examination was unremarkable. Magnetic resonance imaging (MRI) with magnetic resonance angiography (MRA) showed absence of left ICA with an abnormal intercavernous vessel in the sella. Computed tomography (CT) showed absence of the left carotid canal. Doppler ultrasonography (USG) showed high resistance flow in the left common carotid artery (CCA). Since no hemorrhage or aneurysm was seen, patient was managed conservatively and is on regular follow-up. Based on our knowledge, this is the first case to demonstrate the features of unilateral agenesis of ICA with intercavernous anastomosis in X-ray, Doppler USG, CT, and MRI scans of the brain.

A rare case of aneurysm of arc of riolan artery and gastroduodenal artery.

Arc of Riolan is a collateral channel that connects the proximal superior mesenteric artery (SMA) or its middle colic branch and the proximal inferior mesenteric artery or its left colic branch in case of stenosis of either of the arteries. A 65-year-old diabetic female presented with vague abdominal pain. Ultrasonography showed a large aneurysm within the abdomen in the left lumbar region. Computed tomography (CT) angiography done showed severe diffuse atherosclerotic calcification of the abdominal aorta with complete occlusion of the celiac trunk and mild stenosis of SMA origin. The arc of Riolan was seen between the middle colic artery and the ascending branch of the left colic artery, with a large saccular aneurysm in its mid section. No evidence of rupture or hematoma was visible. Another saccular aneurysm was also seen involving the gastro-duodenal and the pancreatico-duodenal collateral arcade. As far as we know, this is the first case of arc of Riolan artery aneurysm to be reported in English literature.