ANAL CANAL
Anal canal
The anal canal is a 4 cm (1 and a half inches) long exit path at the most terminal part of the large intestine. It is situated next to the rectum (storage place for stool). There are multiple muscles around the anal canal called the internal sphincter and external sphincter which helps in maintaining continence of stool and flatus. We have control over only external sphincter. When the bowel movements (stools) leave the body both these sphincters relax to allow the waste to pass through.
- Hemorrhoids
- Fissure
- Fistula in ano
Perianal abscess.
Hemorrhoids
The presence of submucosal tuft of blood vessels cushion is normal and helps in the continence mechanism.
Hemorrhoids (piles) are swelling and engorgement of these blood vessels. When they originate inside the rectum they are termed as internal hemorrhoids and when they develop under the skin around the anus, they are called external hemorrhoids. Even though internal hemorrhoids develop within the anal canal (Grade I & II), with time they will start prolapsing out of the anal canal and patients push them inside manually (Grade III). Rarely prolapsed internal hemorrhoids get swollen and not reducible inside even with effort (Grade IV). Internal hemorrhoids often cause painless bleeding at the onset of defecation. Chronic blood loss can cause anemia (low hemoglobin state). External hemorrhoids are one of the most painful condition affecting anal canal and patients often find it difficult to sit. Blood vessel gets ruptured and clot formation near the anal verge is the cause of pain.
Treatment:
Treatment of piles depends on the stage and type.
Constipation should be avoided by taking a high fiber diet, adequate liquid intake and mediations if required. A topical ointment may be useful. Evacuation of blood clots/ Surgical removal is required to relieve the pain quickly in case of external hemorrhoids.
There are various procedures have been used for internal hemorrhoids like.
- Rubber band ligation
- Sclerotherapy: Injecting chemical solution into piles
- Hemorrhoidectomy (Removal of piles): Using traditional surgical method or newer devices like a harmonic scalpel or Ligature
- Stapler hemorrhoidopexy (Fixing the hemorrhoids from inside): Using a machine called stapler, hemorrhoids are pulled up and fixed. It is a painless procedure.
- DG- HAL (Doppler-guided hemorrhoidal artery ligation): Identifying and ligating the blood vessels that supply hemorrhoids under ultrasound scan guidance.
- Coagulation: This procedure employs lasers, infrared light or heat to harden the internal hemorrhoids, which are small and bleeding. There are only minimal side effects to this procedure and they cause very little discomfort.
Fissure
- Botulinum toxin type A injection: Widely and famously called as botox, this injection aids to paralyze the muscle in the sphincter and help with spasms.
- Surgery – Spasm relieved by severing a portion of internal sphincter under anesthesia. Failed conservative measures, severe spasm or recurrent fissures are the indications for surgery. Surgery is done as a daycare procedure (Discharge on the same day of surgery). A patient needs to continue the sitz bath and other medications for a few weeks after surgery.
An anal fissure is a small cut or crack in the anal canal lining (anoderm), which is a very pain-sensitive part. This is known to cause severe pain and bleeding during and after bowel movements. This happens when hard or bulky stools are passed. Rarely frequent passage of stool also may be the cause. An anal fissure can affect any age group. This is also commonly seen in pregnant females. Torn out skin bulges near the anal verge and mimic like piles. This is called a sentinel pile. The severe spasm of the internal sphincter muscle is the main reason for pain. The posterior midline of the anal canal is the most common site affected.
Treatment:
Treatment is aimed at relieving the internal sphincter spasm and avoiding constipation.
- Sitz bath with warm water – Relaxes internal sphincter and gives significant pain relief.
- Ointment
- Lignocaine – Gives local anesthetic effect and relieve the pain
- Nitroglycerin, Diltiazem, and Nifedipine – Relieve the internal sphincter spasm.
Fistula in ano
When a tunnel develops between the anus and the skin around it, the condition is called anal fistula or fistula in ano. This happens when an infection that starts in the anal gland does not heal properly or fully. When the infection ends in an abscess that drains through the skin around the anus, it leads to the formation of a tunnel under the skin to connect to the infected gland. The only way to treat an anal fistula is through surgery. Oozing of an unpleasant smelling liquid from a hole by the anus is the predominant symptom.
Treatment:
Anal fistulas usually do not heal by themselves and surgery is needed to correct the condition. There are multiple effective surgical procedures available and the right one for the patient will be decided based upon the depth of the fistula. Severing the sphincter muscles is not feasible in deeper fistula as it will lead to incontinence. Contamination of the tract through the internal opening does not allow it to heal even for years. Identifying the internal opening and control the contamination is the key to prevent a recurrence. MRI scan or endo-anal ultrasound scan can be required to get the map of the tract.
- Fistulotomy: This is the most common type of surgery for anal fistulas. In the procedure, the entire length of the fistula is cut open so that it heals as a flat scar. This is best suited for simple fistulas.
- Seton techniques: A piece of thread called the seton is left for multiple weeks in the anal fistula to keep it open. This procedure has opted for fistulas that pass through much of the sphincter muscles. Once open, the fistula drains and heals, avoiding the need to cut the sphincter muscles.
- Bioprosthetic plug: A cone-shaped plug is used to block the internal opening of the anal fistula in this procedure. Insertion of a bioprosthetic plug is one of the safest procedures to block a fistula.
- Ligation of intersphincteric fistulous tract (LIFT) – Identifying and disconnecting the fistulous tract at the intersphincteric plane. This is very useful in complex fistulas.
- Advancement flap procedure – This surgery has opted for fistulas that pass through anal sphincter muscles
Video-assisted anal fistula treatment (VAAFT): In this procedure, firstly an endoscope (a narrow tube with a camera at the end of it) is passed into the anal fistula. This is followed by the passing of an electrode through it to cauterize the fistula tract.
Perianal abscess
Perianal abscess is a painful condition wherein the small anal glands get infected resulting in the collection of pus near the anus. This is extremely painful and needs to be attended immediately.
Symptoms:
- Severe pain in the anal area
- Fever
- Pain during defecation
- Swelling and lump in the anal area
Treatment:
Anal abscesses need drainage on an urgent basis. Once drained, the abscess cavity is left open for the tissue to heal naturally. Patients with large abscess or sepsis will require hospitalization for a few days. To keep you comfortable and help the body to heal properly, the surgeons will prescribe antibiotics and painkillers. The wound will take a few weeks to completely heal. Some patients will form a fistula later in the course which needs to be addressed by another surgery.