T2-weighted images help discriminate cysts from surrounding normal structures. Sublingual glands and their pathologic states are difficult to visualize on ultrasound due to their location. Needle aspiration Analysis of fluid from ranulas demonstrates mucus with prominent histiocytes. The biochemistry of this fluid shows high amylase and protein content. The majority of ranulas demonstrate a cyst devoid of epithelial lining, with the wall composed of vascular fibroconnective tissue resembling granulation tissue.
Histiocytes predominate the pseudocyst wall.
Mucin and foamy macrophages often are seen. Occasionally, partial epithelial linings are observed. Congenital ranulas Some have advocated that all patients with submandibular duct obstruction leading to ranula formation need early marsupialization and ductoplasty to prevent complications such as sialoadenitis. Evidence exists that imperforate ducts may spontaneously resolve if rupture takes place during feeding. Therefore, observation for spontaneous resolution of congenital ranulas is reasonable.