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What is True about features of cholecystitis on USG – a) Thick fibrosed gallbladder wallb) Stone impacted at neck of gall bladderc) Perigallbladder halod) Increased vascularity and explain in detail?
USG findings of acute cholecystitis 

Gallbladder wall thickening
Pericholecyst fluid producing circumferential halo of low echogenicity around gallbladder
Echogenic bile sludge may completely fill the gallbladder lumen and gives appearance of adjacent liver (hepatization of bile)
Gall stone :- May be impacted in the neck or cystic duct
Sonographic murphy's sign (Tenderness on pressing the transducer onto the gallbladder)