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Lateral Internal Sphincterotomy: Before Your Surgery

Picture of anal fistula

What is lateral internal sphincterotomy?

Lateral internal sphincterotomy is surgery to help heal an anal fissure that has not improved with medicine or other treatments. An anal fissure is a tear in the lining of the anus.

During the surgery, the doctor puts a lighted tube (called an anoscope, or scope) into the anus. The doctor is able to see the inside of the anus through the scope. Special surgical tools are guided through the scope into the anus. The doctor uses the surgical tools to make a cut (incision) in the internal anal sphincter. The internal anal sphincter is a ring of muscle that controls the anus. This surgery relieves the pressure and allows the anal fissure to heal.

This surgery may be done while you are completely asleep or while you are awake. If you are awake, you will be given medicine to help you relax. You will not feel pain. The surgery usually takes less than 30 minutes. Most people go home the same day.

Many people notice that the pain from their anal fissure goes away within several days after surgery. But it will probably take about 6 weeks for your anus to completely heal. You will probably be able to go back to work and your usual activities about 1 to 2 weeks after surgery.

How do you prepare for surgery?

Surgery can be stressful. This information will help you understand what you can expect. And it will help you safely prepare for surgery.

Preparing for surgery

  • Be sure you have someone to take you home. Anesthesia and pain medicine will make it unsafe for you to drive or get home on your own.
  • Understand exactly what surgery is planned, along with the risks, benefits, and other options.
  • If you take a medicine that prevents blood clots, your doctor may tell you to stop taking it before your surgery. Or your doctor may tell you to keep taking it. (These medicines include aspirin and other blood thinners.) Make sure that you understand exactly what your doctor wants you to do.
  • Tell your doctor ALL the medicines and natural health products you take. Some may increase the risk of problems during your surgery. Your doctor will tell you if you should stop taking any of them before the surgery and how soon to do it.
  • Make sure your doctor and the hospital have a copy of your advance care plan. If you don't have one, you may want to prepare one. It lets others know your health care wishes. It's a good thing to have before any type of surgery or procedure.

What happens on the day of surgery?

  • Follow the instructions exactly about when to stop eating and drinking. If you don't, your surgery may be cancelled. If your doctor told you to take your medicines on the day of surgery, take them with only a sip of water.
  • Follow your doctor's instructions about when to bathe or shower before your surgery. Do not apply lotions, perfumes, deodorants, or nail polish.
  • Do not shave the surgical site yourself.
  • Take off all jewellery and piercings. And take out contact lenses, if you wear them.
  • You may need to empty your colon with an enema or laxative. Your doctor will tell you how to do this.

The day before surgery

  • Bring a picture ID.
  • The area for surgery is often marked to make sure there are no errors.
  • You will be kept comfortable and safe by your anesthesia provider. The anesthesia may make you sleep. Or it may just numb the area being worked on.
  • The surgery will take about 30 minutes.

When should you call your doctor?

  • You have questions or concerns.
  • You don't understand how to prepare for your surgery.
  • You become ill before the surgery (such as fever, flu, or a cold).
  • You need to reschedule or have changed your mind about having the surgery.

Care instructions adapted under license by your healthcare professional. If you have questions about a medical condition or this instruction, always ask your healthcare professional. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.