Anal Examination Under Anesthesia and Botox Injection for Chronic Anal Fissures
Stanford University School of Medicine
Most individuals associate anal pain with hemorrhoids. However, there are many conditions that can cause anal pain and bleeding, and physical examination helps to differentiate between these diagnoses: anal fissures, hemorrhoids, or infections.
An anal fissure is a superficial tear in the anoderm. Fissures are diagnosed clinically by history and physical exam with careful spreading of the anus and direct visualization of a break in the mucosa and exposed sphincter fibers. Increased tone of the internal anal sphincter can inhibit fissure healing by decreasing blood flow to the mucosa.
Conservative management includes stool softeners and warm sitz baths to avoid traumatizing the fissure with hard stools and relaxing the sphincters with warm water. Topical nitrates or calcium channel blockers applied at the anal verge dilate and relax the internal sphincter muscle to promote healing.
Alternatively, injection of Onobotulinumtoxin A into the fissure and intersphincteric groove paralyzes sphincter muscle, decreasing muscle spasm and supporting healing of the fissure. For individuals who fail these conservative therapies, lateral internal sphincterotomy is considered. This procedure involves dividing the internal sphincter muscles but carries a small risk of fecal incontinence.
This video article presents the case of a young adult male with a history of a chronic anal fissure, who failed medical management. Anal fissure was appreciated on exam and treated with Onobotulinumtoxin A injection for relaxation of anal sphincter.