2 Anatomy of the anal canal The anatomical canal is about 3 cm long and it extends from the anal verge to the dentate lineThe surgical anal canal is about 4 cm long and it extends from the anal verge to the anorectal junction
3 Anatomy of the anal canal Pecten (anoderm) is a hairless part of the external anal canal that exposed by traction on the rim of the anus ( lined by keratinized stratified squamous epithelium )The junction between the Pecten and the large mucosa is known as dentate line .
4 Anatomy of the anal canal The rectum is lined by columnar epitheliumThe transitional zone is lined with cuboidal epithelium that lines the anal canal from the columns of morgagni to the dentate line.Below the dentate line the anal canal is lined by squamous epithelium .
5 Muscle layers of the anal canal Internal sphincter (involuntary ) :is a continuaion of circular smooth of the rectum under control of the autonomic nervous systemExternal sphincter (voluntary ) :downward extension of the puborectalis, witch is striated muscle with somatic innervation ( branch of the internal pudendal nerve S2-S4.
6 Differences between the upper and the lower hlaves of the anal canal according to the dentate line Below the dentate lineAbove the dentate lineEctodermal in originEndodermal in originLined by squamous epitheliumLined by columnar epitheliumUnder control of the somatic innervation (sensitive to pain, touch , temperature)Under control of the autonomic nervous sys. (sensitive to stretch )Drains its venous blood via inferoir rectal vein into the systemic venousDrains its venous blood via the sup.rectal vein to the portal venousDrains its lymph to the inguinal lymph nodes.drains its lymph to the internal iliac lymph nodes.
7 HemorrhoidsDefinition : they are engorgement of venous plexi “cushions” that sit in the anorectal junction.Could be :External: below the dentate lineInternal: above the dentate lineCommonly situated at :3 o’clock “left lateral”7 o’clock “right posterior”11 o’clock “right anterior”
8 Classification of internal hemorroids First degree: painless bleeding usually associated with defecationSecond degree: protrude during defecation but spontaneously reduceThird degree: protrude during defecation and must be manually reducedForth degree: permanently prolapsed
9 Possible causes Constipation Straining Anorectal carcinoma Portal HTN Pregnancy
10 Signs and symptoms Painless bright red rectal bleeding Prolapsing lump ItchingMucus dischargeN.B.sever pain is not typically associated with internal hemorrhoids but is commonly seen with thrombosed external hemorrhoidsbut if pain is present with absence of strangulation look out for other conditions “fissure , hematoma, abcess”
11 Clinical assessment History: Age, type of bleeding, bowel habit Examination:Digital rectal examinationInvestigation:Protoscopy , rigid sigmoidoscopy, colonscopy,Barium enema.
13 Treatment Advice the patient to : receive a high fiber diet use laxativesavoid strainingsitz bathkeep a good hygiene
14 Cont. treatment The definite treatment varies according to the degree of hemorroids:1st degree : sclrotherapyinfrared photocoagulationcryothrapy2nd degree : rubber band ligation3rd and 4th degree : hemorrhoidectomy
15 Cont. treatmentThrombosed external hemorrhoids should be excised if seen within 48 hr, beyond this time, conservative therapy with analgesics and sitz baths is appropriate.
17 Anal FissureDefinition It is painful liner tears in the lining of the anal canal below the dentateline i.e. ( tear in squamous epithelium ).It is the commonest cause of sever anal pain
18 EpidemiologyAcute or chronic tear in the anal canal usually in posterior midline ( M=F in young adult)Anterior fissure is common in Females.Lateral or multiple fissures should raise suspicion of trauma, inflammatory bowel disease ( Chron’s disease), lymphoma, neoplasm or infection.
19 Causes Constipation Inflammatory bowel disease Sexual transmitted diseasePost anal surgery
20 Signs and symptoms burning pain is associated with defecation. Bleeding : the blood is usually bright red and associated with acute fissures.Physical examAcute fissure showing just tear in the anal mucosa.Chronic fissure may reveal a sentinel tag or hypertrophied papilla.