ANAL AND PERIANAL DISORDERS

ANATOMY

Anal canal- 4 cm. long Surrounded by the anal sphincter

mechanism Except during defecation, its lateral walls

are kept in apposition by the levatores ani muscles and the anal sphincters

ANATOMY

Upper half of the anal canal is lined by columnar epithelium

Lower half- stratified squamous epithelium (modified skin)

Dentate line- the junctions of two types of mucosa

THE UPPER HALF

Lined by columnar epithelium Thrown into vertical folds- anal columns Joined together at their lower ends by

small semilunar folds- anal valves At the base of each valve are small

sinuses into which open 4-8 anal glands Some of these glands reach the

intersphincteric spaces and lead to abscess formation

THE LOWER HALF

Lined by stratified squamous epithelium which gradually merges at the anus with the perianal epidermis

There are no anal columns Nerve supply is from somatic inferior

rectal nerve Sensitive to pain, temperature, touch

and pressure

ANAL SPHINCTER MECHANISM

Internal sphincter- thickened continuation of the rectal wall smooth muscles- involuntary sphincter

External sphincter- three parts: subcutaneous, superficial and deep

Puborectalis muscles: cause the rectum to join the anal at an acute angle

ANATOMY

ANATOMY

ANATOMY

ANATOMY

PUBORECTAL SLING

COMMON ANAL SYMPTOMS

ANAL BLEEDING ANAL PAIN PERIANAL ITCHING “SOMETHING COMING DOWN” PERIANAL DISCHARGE

ANAL BLEEDING

Bleeding piles

Anal fissures

Ulcerated anal carcinoma

ANAL PAIN

ANAL FISSURE

COMPLICATED PILES

PERIANAL ITCHING

LOW-GRADE FUNGAL INFECTION

BACTERIAL INFECTION

“SOMETHING COMING DOWN”

PROLAPSED PILES

RECTAL PROLAPSE

PEDUNCULATED ANAL POLYP

PERIANAL DISCHARGE

FISTULA-IN ANO

PROCTITIS

VILLOUS ADENOMA

ULCERATED ANAL CARCINOMA

HEMORRHOIDS

Vascular swellings involving the internal or external venous plexuses

Extremely common- constipation Lack of fiber in the modern ”civilized” diet Unknown in underdeveloped countries

PATHOGENESIS

Excessive venous enlargement at the lower ends of the anal mucosa columns

Usually located at the 3, 7, 11 o’clock positions Caused by straining to pass small hard stools Increased intraabdo. Pressure inhibits venous

return- venous distension Bulging mucosa is dragged distally by the hard

stools Persistent straining at stool causes the pelvic

floor to downwards, extruding the anal mucosa

CLINICAL CIRCUMSTANCES

Chronic constipation Chronic diarrhea Pregnancy Portal hypertension

PILES

INTERNAL PILES

EXTERNAL PILE

SYMPTOMS

Perianal irritation and itching Aching discomfort and pain exacerbated

by defecation Hemorrhoidal prolapse Rectal bleeding

CLASSIFICATION

First degree piles never prolapse

Second degree piles prolapse during defecation but then return spontaneously into the anal canal

Third degree piles remain outside the anal margin unless replaced digitally

COMPLICATIONS

Any piles may bleed from stool trauma during defecation

Large piles may thrombose if they prolapse and their venous return is obstructed by sphincter tone

Venous infarction and ulceration Sphincter tone and spasm aggravate the

pain at defecation and prolapse

PROLAPSED BLEEDING HEMORRHOIDS

DIAGNOSIS

Perianal examination Skin tags Perianal orifices

PR examination palpable, soft folds Rule out malignancy

Proctoscopy Internal piles bulging into the lumenThrombosed piles- congested purplish mass at the

anal margin, tight spasm makes PR exam. PainfulStrangulated piles- necrotic, ulcerated mass

CONSERVATIVE MANAGEMENT

High fiber diet Avoid constipation, straining at

defecation, avoid on the lavatory reading Prolapsd piles should be replaced

digitally after defecation Overuse of creams causes maceration

of the perianal skin

SURGICAL TREATMENT

Injections with irritant solution- fibrotic reaction- atrophy of the piles

Banding- application of Baron’s band

Hemorrhoidectomy- surgical excision

NO PILES

ANAL FISSURE

Longitudinal tear in the mucosa and skin of the anal canal

Caused by passage of a large, constipated stool

Located nearly in the midline of the posterior anal margin

The fissure causes sphincter spasm and acute pain defecation, which persists for up to an hour

ANAL FISSURE

Fresh bleeding at defecation- the bleeding is slight and noted on the toilet paper

History is diagnostic of an anal fissure PR examination is impossible due to

pain Treatment- anal stretch, internal

sphincterotomy

SYMPTOMS

Perianal pain, exacerbated by defecation Minor anal bleeding

PERIANAL ABSCESSES

Presentation: perianal pain, tenderness and swelling

Infection of the anal gland which drain at the base of the anal columns along the dentate line

Duct obstruction by feces may initiate the infection

PERIANAL ABSCESS

Infection tends to spread laterally through the external sphincter

Ischiorectal abscess- Pararectal abscess

Early diagnosis- oral antibiotics treatment may abort the infection

Established abscesses require incision and drainage

PERIANAL ABSCESS

Large ischiorectal abscess requires packing to keep the neck of the cavity open

Granulation tissue gradually fills the space from its depths

PILONIDAL ABSCESS

Occurs in the skin of the natal cleft

Incision and drainage followed by further excision

PILONIODAL ABSCESSTREATMENT

ANAL FISTULA

Develops as a complication of perianal, ischiorectal, pararectal abscesses

Fistula tracks from the lower rectum or upper anal canal through the abscess site to the perianal skin at the point of previous drainage

ANAL FISTULA

Intermittent discharge in the perianal region

A small papilla of granulation tissue is seen on the skin within 2-3 cm. of the anal margin

Blue dye injected into the external orifice Lower fistula- lay open Fistula above puborectalis- banding

ANATOMY

RECTAL PROLAPSE

It is a hernia of the rectum through the pelvic floor- the mucosa and the muscle wall intussuscept through the anal canal

Early stage- prolaps occurs only with defecation and retracts spontaneously

Later stage- the rectum may prolapse when the patient stands up.

The patient reduces the prolapse manually

Rectal prolapse

Rectal prolapse

RECTAL PROLAPSESURGICAL TREATMENT

Wells operation- secure the rectum within the pelvis by fixing it to the sacrum

Ripstein op.- hitching the rectum up to the sacral promontory with a sling

Unfit patients- circum-anal silicone rubber ring

Rectopexy