Rectum

Rectum-

-Anal Fissure-

-An anal fissure is a tear of the anal mucosa
-The goal of treatment is to break the cycle of sphincter spasm and tearing of the anal mucosa to allow for healing of the fissure

-Medical therapy consists of 3 components:  relaxation of the internal sphincter, institution and maintenance of atraumatic passage of stool, and pain  relief

-Most cases this can be accomplished with fiber therapy to keep stools soft and formed and soft, and warm sitz baths following bowel movements to keep the relax the sphincter

-Many topical and injection therapies exist for treatment of this
-Topical Nitroglycerin increases the blood flow and reduces the pressure in the internal anal sphincter which may facilitate healing
-Topical diltazem and bethanechol has also been studied

-Botulinum Toxin has been shown to be helpful in refractory cases
-Oral nifedipine and oral diltazem has been studied and has shown to be beneficial

-Surgical therapy is reserved for those who have failed medical therapy despite adequate medical therapy


-Abscess/Fistula-

-A perianal abscess is an acute phase manifestation of a collection of purulent material that arises from glandular crypts of the anus or rectum

-A perianal fistula represents the chronic phase of suppuration of this perirectal process
-When an abscess is drained or ruptured, an epithelialized track form that connect the abscess in the anus or rectum with the perirectal skin
-Over half of the abscess will develop fistualas
-Other causes of anorectal fistulas include:  Crohn's Disease, Lymphogranuloma Venereum, Radiation Proctitis, Rectal Foreign Bodies, and Actinomycosis
-Surgical treatment is the mainstay of anorectal fistulas

-Perianal abscess traverse distally in the intersphincter groove into the perianal skin where they present as a tender fluctuant mass

-Perianal abscess originates from the infected anal crypt gland

-Patients present with sever pain in the anal or rectal area.  Patients may have fever or malaise

-Imaging studies such as CT scan or MRI is helpful where there is a clinical suspicion of a non palpable abscess

-Treatment involves incision and drainage and antibiotic coverage (Keflex/Bactrim) especially if diabetes or immunosuppression
-Should be cultured


-Fecal Impaction-

-Fecal Impaction is a solid immobile bulk of stool in the rectum
-Should be initially disimpacted manually with manual fragmentation as needed
-After disimpaction is accomplished, an enema with mineral oil will help soften the stool to provide lubrication

-If disimpaction is unsuccessful or partially successful, a water soluble contrast enema such as gastrografin should be administered

-Occasionally fractionation is out of the reach of the finger and will have to be accomplished with sigmoidoscopy


-Hemorrhoids-

-Hemorrhoids are normal vascular structures of the anal canal
-Symptoms of hemorrhoidal disease include anal pruritus, prolapse, bleeding, and pain due to thrombosis

-Hemorrhoids arise from a plexus called a cushion of dilated arteriovenous channels and connective tissue from the superior and inferior hemorrhoidal veins
-The hemorrhoids are located in the mucosal layer in the lower rectum and may be classified internal or external if they are above are below the dentate line.
-The hemorrhoids that above the dentate line are internal hemorrhoids and do not have any sensory innervation.
-Hemorrhoids that below the dentate line do have sensory input and are external hemorrhoids

-Development of hemorrhoids have been associated with advancing age, diarrhea, pregnancy, pelvic tumors, prolonged sitting, straining, and chronic constipation

-Adding fiber to a diet may be beneficial for patients with bleeding from hemorrhoids
-Irritation and pruritus can be treated with topical analgesic creams and hydrocortisone creams/suppositories
-Thrombosed hemorrhoids may need surgical evacuation
-Thrombosed hemorrhoids can be attempted to treated with topical and oral analgesics, stool softeners, and sitz baths

-External hemorrhoids, with the exception of thrombosis, usually do not require surgical therapy
-Some surgeons recommend excision to not to endure recurrent thrombosis
-Failure of medical therapy can be an indication for excision of external hemorrhoids also

-Internal hemorrhoids can be treated with rubber band ligation, infrared coagulation, bicap, laser photocoagulation, sclerotherapy, and cryosurgery


-Rectal Neoplasms-

-The goal of treatment of rectal cancer is surgical resection
-Radiation therapy and chemotherapy is often given preoperative to help improve cure rates

-Locally advanced disease is defined as a lesion that cannot be resected without a  high likelihood of leaving microscopic or gross residual disease at the site because of tumor adherence of fixation
-A locally advance lesion can arrange from a tethered or marginally resectable tumor to a fixed cancer that direct invades adjacent structures

-Pretreatment evaluation rests on its physical exam inaction and CT or MRI appearance
-Majority of rectal cancer is adenocarcinoma

-The goal of pretreatment is to shrink the tumor down enough where it can be resected