Overview
Definition:
An anal fissure is a linear tear or ulcer in the anoderm, typically located in the posterior midline
It is often associated with severe pain, particularly during defecation, and bleeding
Anal dilatation refers to the mechanical or surgical widening of the anal canal to relieve spasm and promote healing.
Epidemiology:
Anal fissures are common, affecting all age groups, but are most prevalent in young to middle-aged adults (20-50 years)
They are equally common in males and females
Chronic constipation and forceful defecation are significant risk factors.
Clinical Significance:
Anal fissures are a frequent cause of anorectal pain and bleeding, significantly impacting quality of life
Understanding their management is crucial for surgical residents to provide effective relief and prevent complications, essential for DNB and NEET SS examinations.
Clinical Presentation
Symptoms:
Severe, sharp, tearing pain during defecation
Bright red blood on toilet paper or stool
Pain may persist for minutes to hours after defecation
A palpable or visible skin tag (sentinel pile) at the external end of the fissure in chronic cases
Sensation of incomplete evacuation.
Signs:
Visual inspection may reveal a fissure in the anal canal, often difficult to visualize due to patient discomfort and anal sphincter spasm
In chronic fissures, a hypertrophied anal papilla may be present proximally and a sentinel pile distally
Digital rectal examination is often painful and may be deferred.
Diagnostic Criteria:
Diagnosis is primarily clinical, based on characteristic symptoms and physical examination findings
There are no specific laboratory or imaging criteria for diagnosis
the condition is confirmed by visual identification of the fissure and associated findings.
Diagnostic Approach
History Taking:
Detailed history of pain characteristics (onset, severity, duration, triggers)
History of constipation, diarrhea, or previous anorectal surgery
Rule out other causes of bleeding and pain: hemorrhoids, inflammatory bowel disease, infections, malignancy.
Physical Examination:
Gentle inspection of the perianal region
If pain allows, gentle separation of the buttocks to visualize the anal canal
In cases of significant pain or suspicion of other pathology, examination under anesthesia may be required
Examination should be systematic to assess for sentinel piles, anal tone, and any other lesions.
Investigations:
Generally, no investigations are required for typical anal fissures
Anoscopy or proctoscopy may be performed if the diagnosis is uncertain or to rule out other pathologies like fistulae or malignancy
Biopsy is rarely indicated unless the fissure is atypical or refractory to treatment, to rule out Crohn's disease or malignancy.
Differential Diagnosis:
Hemorrhoids (internal and external)
Anal abscess and fistula
Proctitis
Sexually transmitted infections (e.g., syphilis, herpes)
Crohn's disease
Malignancy (anal squamous cell carcinoma, adenocarcinoma).
Management
Initial Management:
Conservative measures are the first line of treatment
Focus on pain relief and promoting healing
This includes dietary modifications, stool softeners, sitz baths, and topical medications.
Medical Management:
Dietary fiber supplementation and adequate fluid intake to ensure soft stools
Stool softeners (e.g., docusate sodium, psyllium)
Sitz baths (warm water immersion) 2-3 times daily for 15-20 minutes to relax the sphincter and promote healing
Topical agents: topical anesthetics (lidocaine 2%) for pain relief
topical nitrates (glyceryl trinitrate 0.2% ointment) to improve blood flow and reduce sphincter tone
topical calcium channel blockers (e.g., nifedipine 0.2% ointment) for similar effect
Botox injections into the internal anal sphincter can also be considered to reduce spasm.
Surgical Management:
Surgical options are considered for chronic, refractory fissures or those with a sentinel pile
Lateral internal sphincterotomy (LIS) is the gold standard, involving division of a portion of the internal anal sphincter to relieve spasm and improve blood flow
Anal dilatation (manual or pneumatic) can be an alternative or adjunct procedure, but carries a risk of incontinence
Fissurectomy with sphincterotomy may be performed for fissures with significant scarring or sentinel piles.
Supportive Care:
Patient education regarding diet, fluid intake, and hygiene
Adequate pain control is paramount
Monitoring for signs of infection or complications
Follow-up appointments to assess healing and recurrence.
Complications
Early Complications:
Pain
Bleeding
Infection
Incontinence (temporary or permanent, especially after sphincterotomy)
Anal stenosis (rare with modern techniques).
Late Complications:
Recurrence of fissure
Chronic anal pain
Chronic sentinel pile which may require excision
Long-term incontinence (more common with extensive sphincterotomy).
Prevention Strategies:
Prevent constipation through high-fiber diet and adequate hydration
Avoid straining during defecation
Prompt treatment of acute fissures with conservative measures
Careful surgical technique to minimize risk of sphincter damage during LIS.
Prognosis
Factors Affecting Prognosis:
Acute fissures generally heal well with conservative management
Chronic fissures, especially those with a sentinel pile or significant sphincter spasm, have a higher recurrence rate or may require surgery
Patient adherence to lifestyle modifications is key.
Outcomes:
Over 90% of acute fissures heal with conservative treatment
Surgical treatment, particularly LIS, has a high success rate (over 95%) in healing chronic fissures
Recurrence rates are generally low but can occur.
Follow Up:
Regular follow-up is recommended, especially after surgical intervention, to monitor for healing, recurrence, and any potential complications like incontinence
Patients should be advised on long-term preventive measures.
Key Points
Exam Focus:
Understand the pathophysiology: anal sphincter spasm leading to ischemia
Differentiate between acute and chronic fissures
Know the conservative management steps (diet, sitz baths, topical agents)
Primary surgical intervention for chronic fissures is Lateral Internal Sphincterotomy (LIS)
Risk of incontinence with LIS.
Clinical Pearls:
A very painful digital rectal exam is often a hallmark of a fissure
Always assess for sentinel pile in chronic fissures
Topical nitrates or calcium channel blockers are effective medical treatments
LIS is highly effective but requires careful technique to avoid overtightening and subsequent incontinence.
Common Mistakes:
Aggressive digital examination in a patient with acute fissure causing extreme pain and potential worsening
Prescribing strong laxatives that can cause diarrhea and worsen irritation
Delaying surgical referral for chronic, non-healing fissures
Over-reliance on topical treatments without addressing underlying constipation.