Turtleback sign
Turtleback sign, also known as tortoise shell appearance, represents a characteristic appearance of chronic hepatic schistosomiasis in which liver margins are irregular and nodular. Dystrophic calcifications within a polygonal network of fibrous septa are seen in the periphery, often perpendicular to the liver capsule, resembling the turtle's carapace. It is considered pathognomonic for hepatic schistosomiasis due to Schistosoma japonicum and Schistosoma mansoni .