Imaging of acute cholecystitis and cholecystitis-associated complications in the emergency setting.

Acute cholecystitis is a common cause of right upper quadrant pain in patients presenting at the emergency department. Early diagnosis and recognition of associated complications, though challenging, are essential for timely management. Imaging studies, including ultrasonography, computed tomography and magnetic resonance imaging, are increasingly utilised for the evaluation of suspected cases of cholecystitis. These investigations help in diagnosis, identification of complications and surgical planning. Imaging features of acute cholecystitis have been described in the literature and are variable, depending on the stage of inflammation. This article discusses the spectrum of cholecystitis-associated complications and their imaging manifestations. We also suggest a checklist for the prompt and accurate identification of complications in acute cholecystitis.

Computed Tomography Features of External Auditory Canal Cholesteatoma: A Pictorial Review.

Computed tomography (CT) is widely used for evaluation of patients with otologic conditions. External auditory canal cholesteatoma (EACC), although rare, demonstrates characteristic CT appearance. Moreover, the accurate extent of involvement cannot be accurately assessed clinically. This pictorial review aims to illustrate the spectrum of CT features of EACC and highlight the key features that are useful for making an accurate diagnosis of this condition. We have also discussed the radiological and clinical differential diagnoses of external auditory canal lesions that can be mistaken for an EACC.

Clinics in diagnostic imaging (152). Right lower lobe segmental pulmonary embolus.

A 56-year-old man presented to the Accident and Emergency Department with pleuritic chest pain of sudden onset. He gave a history of short-distance air travel ten days earlier. Chest radiograph showed a peripheral-based opacity in the right lower zone, which was not seen in a previous study done three months ago, suggestive of Hampton's hump. The D-dimer level was raised. Computed tomography pulmonary angiography confirmed the diagnosis of pulmonary embolism in a right lower lobe segmental branch, with adjacent collapsed lung, consistent with lung infarction. The patient was started on heparin injection with significant relief of his symptoms. The clinical and imaging features of pulmonary embolism are described, with emphasis on the historical radiographic signs and the current dual-energy computed tomography innovations.

Clinics in diagnostic imaging. 145.

A 63-year-old man presented with painless jaundice, loss of appetite and significant weight loss. Cross-sectional imaging showed a diffusely enlarged pancreas, with no significant fat stranding and a hypodense rim on computed tomography, which appeared hypointense on T2-weighted magnetic resonance imaging. There was a narrowed pancreatic duct and features of common bile duct narrowing in the region of the pancreatic head. However, there was no obvious mass seen in the pancreatic head region. These features were classical of autoimmune pancreatitis with diffuse involvement of the gland. Laboratory investigation showed abnormal liver function and the classical sign of raised immunoglobulin G class 4 antibodies. The patient showed dramatic response to high-dose steroids, with resolution of both the laboratory and imaging abnormalities within one month. We discuss the classical imaging features of Type 1 autoimmune pancreatitis, an uncommon condition that needs to be differentiated from pancreatic malignancy.