BENIGN ANAL CONDITIONS

Surgery Lectures, S1

WINA, F M.

OUTLINE

1. ANORECTAL ABSCESSES
2. FISTULA – IN – ANO
3. HAEMORRHOIDS
4. FISSURE IN ANO
5. RECTAL PROLAPSE

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ANATOMY OF THE RECTUM & ANAL CANAL

• Rectum is distal 15cm terminal portion of large intestine and anal canal is approx. 4cm of GI tract.
• Rectum: 4 layers; mucosal, submucosal, 2 smooth muscle layers.
• Anal canal: internal sphincter, external sphincter, intersphincteric plane
• Dentate line – dividing neurovascular supply

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• Aorta

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Endodermal

Ectodermal

Columnar

Squamous

Autonomic

Somatic

Superior rectal artery; portal drainage

Inferior Rectal artery; systemic drainage

Lymph to inguinal nodes

PECTINATE/DENTATE LINE

ANORECTAL ABSCESSES

• DEFINATION:
• suppuration of anorectal region, usually arise from inflammation of inter-sphincteric anal glands leading to abscess formation

CLASSIFICATION

• Intersphincteric
• Ischiorectal -30%
• Perianal- 50%
• Supralevator-< 5%
• Intramuscular
• Submucosal
• Subcutaneous

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AETIOPATHOGENESIS

• Aetiology

-60 %- E.coli

-23% -Staph. Aureus

-others Bacteriodes, Steptococcus, Proteus

- mixed infection

• Others-Penetration of rectal wall by fish bone

-Blood borne infection

-Extension of cutaneous boil

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Underlying rectal Dx

- neoplasm

- Crohn’s dx

- actinomycoses, Tuberculosis, Chlamydial inf.

Immunoincompetence

- DM, AIDS, Pt on cytotoxic drugs

- Trauma/surgery

Anal fissure

Radiotherapy for anorectal ca, ca prostate

CLINICAL FEATURES

• History

-pain –throbbing ,worse with movement, sneezing,^ intraabdominal pressure

-swelling(+ pain)- about 95%

-fever 12%

-Perianal discharge 12%

-diarrhoea

-skin excoriation

-external opening

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• Past medical hx

Trx for inflammatory bowel dx, diverticulitis

radiotherapy for anorectal Ca, Ca prostate

Trx for rectal, anal, Perianal dx, Trx for AIDS, Trx for Tb

Drug hx : steroid, cytotoxic drugs, immunosuppressant drugs

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• Review of systems

weight loss

abdominal pain

change in bowel habit

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• Diff. Diagnosis

Hidadenitis suppurativa

Infected inclusion cyst

Pilonidal abscess

Bartholin gland abscess

Periprostatic abscess

Inflammatory bowel disease

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• Examination- mainstay of diagnosis
• -general
• -perineum
• -acutely tender swelling at anal verge- Perianal fluctuant swelling in Ischiorectal fossa, external openings +/- discharge needle aspiration

DRE

acute inflammatory pain may preclude further exam

Proctoscopy- internal opening of fistula bulging abscess – lntersphincter, submucous, ischiorectal

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INVESTIGATION

Clinical presentation and co-morbid condition of patient determine the extent of investigation

General

FBC, Aspirate for m/c/s

others- RBS, Urinalysis, RVS, Mantoux test, VDRL test

Specific

EUA- investigation, Trx

Sigmoidoscopy,

Colonostomy.

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INVESTIGATION

Radiological investigation

• indicated in Patients with recurrent abscesses or abscess associated with complex fistula

-Sinography/fistulography

-Transrectal/Transanal USS

-Contrast study –Barium enema, upper GI series

-CT Scan

-MRI ( endorectal coil)

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TREATMENT

• Principle of treatment

-sepsis control by adequate drainage of abscess

- preservation of faecal continence

- no place for use of antibiotics only,

- site of abscess determines direction of drainage and subsequent mgt

- pain relieve and choice of anaesthesia

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TREATMENT

• Perianal- I &D ,cruciate incision , deroofing of abscess cavity
• Ischiorectal – 2 stage procedure; 1^st- I&D, cruciate incision, deroofing of abscess

2^nd stage- EUA for fistula opening& Trx of fistula, if no fistula light packing with gauze,

• Submucosal – opening with sinus forceps(proctoscope)
• Intersphincteric and intramuscular- internal sphincterotomy

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TREATMENT

• Supralevator- through the rectum
• Horseshoe abscess- drainage through midline incision posterior to anus/rectum + counter drainage place in each ischorectal fossa
• Treat underlying conditions or co-morbidities.

COMPLICATIONS

• Complications of dx/Complications of the treatment

-acute – urinary retention, bleeding, faecal impaction, thrombosed haemorrhoid

- Fistula

-Recurrent abscess

-Necrotizing infection of the perineum

-Faecal incontinence

-Cancer of fistula tract- rare

- Septicaemia

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FOLLOW-UP

• Sitz bath
• Digital examination
• Healing expected by 6wks
• Recurrent/non-healing- indication for more investigation to R/O fistula
• Wound dressing

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FISTULA-IN-ANO

• FISTULA – IN – ANO is a track lined by granulation tissue or epithelium connecting the anal or rectal mucosa with the perianal skin.
• This is usually the chronic phase of Anorectal abscess.
• Anorectal abscess and fistula are largely different phases of same disease.

AETIOPATHOGENESIS.

• IT is linked to that of anorectal abscess.
• Via pyogenic infection of anal crypts --> intersphincteric abscess.

2. Via a badly drained anorectal abscess whatever its aetiology

3. Granulomatous conditions: TB, Amoebiasis, Actinomycosis, Schistosomiasis, Lymphoma, Ulcerative colitis, Crohn’s disease.

4. OTHERS : - Cancers of the anorectum.

- Previous surgical & obstetric operations with infected badly healed perineal wounds.

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Classification:

1. Based on position of the internal opening
1. High – at or above the anorectal ring.
2. Low - Below the anorectal ring.

1 . High fistula – pelvirectal (supralevator),

- High intersphincteric,

- High submucous.

2. Low level fistula – Submucous

- Subcutaneous

- Intermuscular(low anal).

B. Based on plane of the tract – Park’s classification.

1 . Intersphincteric – most common, tract confined to this space.

Classification.

2. Trans-sphincteric – Tract connects the inter-sphincteric tract to the ischiorectal fossa passes through the external sphincter.

3. Supra- sphinteric – Tract loops over external sphincter & perforates the levator ani.

4. Extra-sphincteric – Tracts from rectum to perianal skin, external to the sphincter complex.

Clinical Features.

• PERIANAL DISCHARGE: Seropurulent fluid, faeces, flatus.

Usually initially a boil ( peri anal). The discharge maybe intermittent with superficial healing.

• PAIN – Pus accumulation, Fissure-in-ano.
• There maybe other histories suggestive of aetiology of the preceding anorectal abscess.

Examination.

• OPENING- Usually elevated, indurated, some times inflamed exuding pus.

Maybe healed over & seen with difficulty.

• INTERNAL ORIFICE – in the anorectum

Salmon-Goodsall’s Law illustrated

INVX

• FISTULOGRAM – Identifies tract of fistula & also complex fistulae
• OTHERS – As in Anorectal abscess

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TREATMENT.

1. LOW LEVEL FISTULA:
1. Fistulotomy – with deroofing.
2. Fistulectomy – Anterior non inflammed & non infected fistula.
3. Park’s operation – drains intersphincteral region by internal sphincterotomy, then lays open the part lateral to the external sphincter.

TREATMENT – High level fistula.

1. SETON: Main track into the rectum is identified and a stout silk or linen ligature(SETON) is passed through it and tied loosely around the remaining part of the external anal sphincter.

2. Two- staged treatment.

COMPLICATIONS.

• Sepsis.
• Anal incontinence.
• Psychological depression.

HAEMORRHOIDS

• Symptomatic anal cushions.

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• Haemorrhoidal venous cushions are normal structures
• of anorectum and universally present in all persons.

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AETIOLOGY

• Constipation
• Pregnancy
• Obesity
• Prolonged sitting
• Chronic diarrhea
• Chronic cough
• Straining e.g. in BPH, CaP

• Colon cancer
• Portal hypertension and anorectal varices
• Inflammatory bowel disease
• Rectal surgeries
• Familial
• Smoking

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CLASSIFICATION

• Internal haemorrhoids
• External haemorrhoids
• Mixed haemorrhoids

• GRADE I painless bleeding, no prolapse.
• GRADE II prolapse on defecation that reduces spontaneously.
• GRADE III prolapse that has to be digitally reduced
• GRADE IV Permanent Prolapse.

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CLINICAL FEATURES

• Painless bleeding
• Anal Prolase
• Perianal Pruritus
• Perianal pain
• Skin tags
• P/R Examination

INVESTIGATION

• Proctoscopy
• Sigmoidoscopy
• Colonoscopy
• Others

TREATMENT

• Conservative
• Sitz bath
• High fibre diet
• Topical analgesics
• Stool softeners

Minimally invasive techniques

• Rubber band ligation
• Sclerotherapy
• Coagulation
• Electrocautery
• Cryosurgery
• Use of Laser

Surgery

• Haemorrhoidectomy – open or closed
• Stapled haemorrhoidopexy

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COMPLICATIONS OF HAEMORRHOIDECTOMY

• EARLY:
• Haemorrhage
• Acute urinary retention
• Anorectal abscess
• Anal fissure

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• LATE
• Anal stenosis/stricture
• Incontinence

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COMPLICATION OF HAEMORRHOIDS

• Strangulation and thrombosis
• Ulceration
• Gangrene
• Fibrosis
• Anorectal abscess
• Portal pyaemia
• Massive lower GI bleeding

DIFF DIAGNOSIS

• RECTAL PROLASE
• RECTAL/ANAL CANCER
• ANAL WARTS
• RECTAL POLYPS
• PERIANAL ABSCESS
• IBD

ANAL FISSURE�

• A painful linear ulcer in the longitudinal axis of the lower anal canal.
• Occurs commonly in the midline.
• Posterior fissure more common in males while anterior fissures commoner in females.
• Lateral Fissures are usually due to IBD, AIDS, TB, etc.
• Aetiology: Hard stools, Haemorrhoidectomy, IBD.

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CLASSIFICATION/PATHOLOGY

• ACUTE
• CHRONIC

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• Acute Fissures- a deep linear wound with exposed anal sphincter or granulation tissue.
• Chronic Fissures – linear ulcer with induration of the lateral edges, has a proximal hypertrophied anal papilla and distal sentinel pile.

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TREATMENT

• CONSERVATIVE – Pharmacologic sphincterotomy using topical agents like GTN, Diltiazem, Nifedipine ointment, Botox.

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• OPERATIVE – Internal sphincterotomy, Anoplasty, Classic Excision.

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RECTAL PROLASE�

• Defined as circumferential descent of the bowel through the anus,
• Types
• 1. Incomplete or mucosal prolapse
• 2. Complete Prolapse

• Aetiology
• Increase intra-abdominal pressure
• Change in bowel habit
• Atony of anal canal
• Prolapsing haemorrhoids
• Hind gut motility disorder
• Central nervous system disease.

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• TREATMENT
• Non-operative
• Operative
• COMPLICATIONS
• Ulceration and haemorrhage
• Irreducibility
• Rupture of the prolapse
• Differential diagnosis
• Prolapse rectal polyp
• Intussusception protruding through the anus

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ADDITIONAL READING

• PILONIDAL SINUS
• PERIANAL WARTS

CONCLUSION

• BENIGN ANAL CONDITIONS commonly occur, patients usually present when symptoms are unbearable,
• There are varied differentials of benign anal conditions.