Rectal EUS is indicated to stage rectal cancer by clarifying depth of invasion, involvement of adjacent structures, and presence of lymph nodes, but magnetic resonance imaging (MRI) is the recommended modality unless there is a contraindication.
EUS is also used to assess for vascular lesions, primarily rectal varices. Anal EUS can be used to clarify the extent of anal sphincter injury. Finally, EUS is used to assess for perianal, perirectal, and pelvic disease in IBD and can be used to follow response to therapy. EUS-guided therapeutics including abdominopelvic fluid collection drainage, fiducial placement, rectal varix treatment, and targeted microbubble drug delivery are available in varying degrees and have been evaluated in retrospective case series .
In the current issue of Afro-Egyptian Journal of Infectious and Endemic Diseases (AJIED) Mahran et al, discussed the role of EUS in diagnosis of rectal and perianal lesions. This study is one of few studies that focused on the role of EUS in evaluation of rectal and perirectal lesions and its ability to detect malignancy in such lesions depending on its high resolution imaging, elastography and EUS-FNA with its great benefit in tissue acquisition for histopathological evaluation.