Review of Various Perianal Lesions on CT and MRI.

The perianal area consists of complex and diverse anatomical structures. Various conditions can affect this area, including inflammatory diseases, such as perianal abscesses, fistulas, and condyloma acuminata, and malignant tumors, such as mucinous adenocarcinoma, squamous cell carcinoma of the rectum, and squamous cell carcinoma of the anus. Due to the small size of the perianal area, lesions may be easily overlooked. However, with advancements in imaging technology, perianal lesions can now be identified using CT and MRI, aiding in the planning of treatment strategies. This pictorial essay aims to present the CT and MRI findings of normal anatomical structures around the anus and the inflammatory and malignant lesions affecting the perianal region. Key considerations for the detection of each condition are also discussed.