Anatomy and Imaging Techniques Anatomy Couinaud classification The liver is subdivided anatomically into 8 segments; segments II – VIII are divided anatomically via the portal and hepatic veins The caudate lobe (segment I): this is autonomous, receiving vessels from both…
Ulcerative Colitis and Toxic Megacolon Ulcerative Colitis (UC) Definition A relapsing and remitting inflammatory bowel disease predominantly involving the colorectal mucosa and submucosa ▸ there is symmetrical colonic involvement (cf. asymmetrical Crohn's disease) It always involves the rectum – any…
Crohn's Disease (CD) Crohn's Disease Definition A chronic progressive transmural granulomatous inflammatory bowel disease There are typically discontinuous (‘skip’) lesions with asymmetrical bowel wall involvement It can affect any part of the GI tract – however it almost always affects…
Peptic Ulceration, Gastric Heterotopia, Duodenal Diverticula Peptic Ulceration Definition Mucosal ulceration occurring within an acidic part of the GI tract ▸ it is often associated with H. pylori infection ▸ duodenal ulcers are 2–3x more common than gastric ulcers ▪…
Benign Gastric Ulcers Benign Gastric Ulcers Definition Gastric ulcers penetrate the stomach wall through the mucosa and into the submucosa (and frequently also into the muscularis propria) ▸ 95% are benign and they can also be multiple Causes Helicobacter pylori…
Hiatus Hernia and Reflux Hiatus Hernia Definition Protrusion of part of the stomach through the diaphragmatic oesophageal opening ▪ Type 1 – sliding hernia (the commonest type): the gastro-oesophageal junction (GOJ) slides proximally through the diaphragmatic hiatus to assume an…
Conventional Coronary Angiography and Echocardiography Conventional Coronary Angiography This involves the selective injection of contrast medium into the right and left coronary arteries and the left ventricle (while recording the resultant moving images) Being replaced by non-invasive CCT and CMR…
Gastrointestinal Vascular Disorders Mesenteric Haemorrhage Upper gastrointestinal (GI) haemorrhage This is defined as bleeding proximal to the duodenal–jejunal flexure (most commonly from the left gastric artery) Causes: peptic ulceration ▸ pancreatitis ▸ gastro-oesophageal varices ▸ as a complication of endoscopic,…
Aortic Rupture Traumatic Aortic Injury (TAI) Definition This occurs as a result of a rapid deceleration injury generating shearing forces at the aortic isthmus ▸ other mechanisms of injury include an AP compression force displacing the heart to the left…
Pulmonary Thromboembolic Disease Pulmonary Thromboembolic Disease Definition A pulmonary embolus (PE) usually arises from a thrombus within a pelvic or lower limb vein (>90%) ▪ ‘Saddle’ embolus: a thrombus lodged at the main pulmonary arterial bifurcation ▪ Pulmonary infarction: This…