Lateral Internal Sphincterotomy (LIS) - Notaras Technique

Why is it done?

The Two Methods

🔒 Closed Method

1. The surgeon inserts a No. 11 blade (a pointed scalpel) into the intersphincteric groove - the natural groove between the internal and external sphincter muscles
2. The blade is passed upward below the dentate line (the junction line inside the anal canal)
3. The blade is then turned inward (medially) and used to cut through the lower 1/3 to 1/2 of the internal sphincter
4. No external skin cut is made - hence "closed"

🔓 Open Method

1. The skin is cut on the side (laterally), just outside the anal opening (anal verge)
2. The surgeon directly sees and dissects the thickened (hypertrophied) lower band of the internal sphincter
3. The muscle band is cut and divided under direct vision
4. The wound is left open to heal on its own

Key Landmarks to Know

Summary

Fissurectomy - Simple Explanation

Why is it done?

• Hardened/fibrosed edges that won't heal
• A sentinel pile (skin tag) at the outer edge
• A hypertrophied anal papilla at the inner edge
• Scarred tissue at the base

What is Removed? (The "Triad")

Step-by-Step Procedure

• Patient placed in lithotomy or prone jack-knife position
• Anal canal is gently stretched/dilated to expose the fissure (usually at 6 o'clock - posterior midline)

• The skin tag (sentinel pile) at the anal verge is grasped and cut away
• This is the "entry point" of the excision

• The entire fissure - including its thickened, fibrosed edges and scarred base - is excised as an ellipse
• Healthy bleeding tissue is the goal (shows you've gone deep enough)

• The enlarged papilla at the dentate line (top of fissure) is also removed

• The wound is left open (not stitched) - this is important
• It heals by secondary intention (granulation tissue fills it from the base up)

Key Points

Fissurectomy vs Sphincterotomy - Quick Compare

Bottom Line

🔪 Fissurectomy - Detailed but Simple

First, What is a Chronic Anal Fissure?

NORMAL FISSURE → CHRONIC FISSURE
    (fresh tear)        (scarred, fibrosed)
                              ↓
                    Develops 3 changes:
              1. Hard fibrotic edges (like scar tissue)
              2. Sentinel pile below (swollen skin tag)
              3. Hypertrophied papilla above (thickened tag)

What Does Fissurectomy Do?

"Surgical excision of a fissure involves excising the fibrotic edge, curettage of the base, and excision of the sentinel tag and/or anal papilla."

• Bailey and Love's Surgery, 28th Ed.

The Anatomy - What You're Working With

        ↑  (inside/up)
   
  [Hypertrophied Anal Papilla]  ← at the DENTATE LINE (top)
           |
    [THE FISSURE]               ← in the midline (6 o'clock)
     - fibrotic hard edges
     - unhealthy scarred base
           |
  [Sentinel Pile/Tag]           ← at the ANAL VERGE (bottom)
  
        ↓  (outside/down)

Step-by-Step Procedure (Very Simple)

Step 1 - Patient Positioning

• Lithotomy position (on back, legs up) OR prone jack-knife (face down)
• General or spinal anaesthesia
• Fissure is almost always at 6 o'clock (posterior midline)

Step 2 - Expose the Area

• A retractor (proctoscope or anal retractor) is gently placed to open and see the anal canal
• The fissure, sentinel pile, and papilla are all identified

Step 3 - Remove the Sentinel Pile (Start From Below)

• Grab the sentinel pile (the skin tag at the anal verge) with forceps
• Cut it away from the skin
• This is the starting point of the excision

Step 4 - Excise the Fissure Itself

• Using scissors or a scalpel, the fissure is excised as an ellipse shape
• The hard fibrotic edges on both sides are cut away
• The surgeon goes down to the base of the fissure to ensure all unhealthy tissue is removed
• The base is curetted (scraped) to remove any remaining scarred/unhealthy tissue
• You want to see fresh, bleeding, healthy tissue at the end - this means you've gone far enough

Step 5 - Remove the Hypertrophied Papilla (Top)

• The enlarged papilla sitting at the dentate line (top end of the fissure) is identified
• It is excised/snipped off
• This completes the excision of all three components

Step 6 - The Wound is LEFT OPEN

• The wound is NOT sutured or closed
• It is left open to heal by itself from the bottom up (secondary intention)
• This prevents infection and abscess formation

What Happens After? (The Healing Process)

Day 0    → Raw open wound after surgery
Week 1-2 → Granulation tissue starts forming from the base
Week 3-4 → Wound fills in gradually from below
Week 6-8 → Complete healing (re-epithelialization)

When is Fissurectomy Done?

"Fissurectomy is an alternative to lateral internal sphincterotomy and is used if there are contraindications to lateral internal sphincterotomy. It is frequently combined with an advancement flap anoplasty."

• Bailey and Love's Surgery, 28th Ed.

Fissurectomy Alone vs Combined

"It has limited success when used alone but may be performed in conjunction with chemical denervation, sphincterotomy, or advancement flaps."

• Current Surgical Therapy, 14th Ed.

What is an Advancement Flap? (Quick Note)

• A piece of healthy perianal skin is lifted (like a flap) with its blood supply intact
• It is slid (advanced) upward to cover and fill the fissure wound
• Sutured with absorbable stitches
• This brings fresh, well-vascularized tissue to a previously poor blood supply area

Key Numbers to Remember

One Line Summary

Fissurectomy = Cut out everything bad (fissure + sentinel pile + papilla), scrape the base clean, leave the wound open, and let the body heal fresh from scratch.