Rectum And Anus

Question 1

Layers of the colon and rectum:

Answer 1

1. mucosa
2. submucosa
3. Inner circular muscle ( creats the internal anal sphincter)
4. outer longitudinal muscle
5. serosa

Question 2

Anatomical anal canal made of =

Surgical anal canal made of=

Answer 2

Dentate line and anal verge

-anorectal ring, dentate line and anal verge

Question 3

Colorectal and anorectal vascular supply:

Answer 3

Arterial supply for the colon: 
1) superior mesenteric artery branches 
  ▪️ileocolic artery 
  ▪️ right colic artery 
  ▪️middle colic artery 
2)inferior mesenteric artery;
  ▪️left colic artery 
  ▪️sigmoid branches
  ▪️superior rectal artery 
3)internal iliac artery branches:
  ▪️middle rectal artery
  ▪️internal pudendal artery branch

Question 4

Venous drainage:

Answer 4

1) superior rectal vein
2) middle rectal vein
3) inferior rectal vein

Question 5

Colorectal and anorectal nerve supply:

Answer 5

• parallel to the course of arteries:
  1) sympathetic (inhibitory) arise from t6-t12 and L1-L3
  2) parasympathetic (stimulatory) , vagus nerve to right and trnasverse colon , s2-s4 left colon
• external anal sphin. And pubotectalis muscle -> internal pudendal nerve
• levator ani- internal pudendal nerve +branches od s3-s5

Question 6

Anal canal is sensate

Rectum is relatively insensate

Question 7

Clinical evaluation :

Answer 7

🔸endoscopy:

1) anoscopy: examination of the anal canal , it can be diagnostic and therapeutic tool
2) proctoscopy: examination of the rectum and distal sigmoid colon , occasionally used therapeutically

Question 8

Imaging:

Answer 8

1) plain x ray of abdomen
2) contrast studies
3) CT
4) MRI
5) Positron emission tomography(PET)
6) angiography
7) endorectal and endoanal US

Question 9

Anorectal Hemorrhoids:

Answer 9

• cushions of submucosal tissue containing venules , arteriols and smooth muscle fibers that are located in the anal canal
• 3cushions : left lateral, right anterior and right posterior , thought to function as part of the continence mechanism

Question 10

Classification of hemorrhoids:

Answer 10

1) external hemorrhoids -distal to dintate line
2) internal hemorrhoids - proximal to dintate line ( are grouped into 4 stages , 1: that bleed, 2: cause bleeding and prolapse but return by themselves, 3:bleed and prolapse but require manual replacement , 4: do not return into anal canal
3) combined internal and external horrhoids
4) postpartum hemorrhoids
5) rectal varices: may result from portal hypertension

Question 11

Treatment of hemorrhoids:

Answer 11

✅medical therapy : (dietary fiber , stool softeners , increased fluid intake and avoidance of straining ) STAGE 1+2
✅rubber band ligation , sclerotherapy , infrared photocoagulation, laser ablation, carbon dioxide freezing, lord dilation
1 +2 and selected 3 hemorrhoids
✅excision of thrombosed external hemorrhoids

Question 12

Sclerotherapy=

Answer 12

Treatment of early internal hemorrhoids

Question 13

Operative hemorrhoidectomy=

Answer 13

Based on decreasing blood flow to the hemorrhoidal plexuses and excising redundant anoderm and mucosa

1) closed submucosal hemorroidectomy
2) open hemorroidectomy
3) stapled hemorrhoidectomy
* preoperative details= performed by using local anesthesia with IV sedation or general/regional anesthetic techniques + simple rectal evaquation

Question 14

Complications of hemorroidectomy:

Answer 14

1) postoperative pain - oral narcotics , NSAIDs, muscle relaxants , topical analgesics
2) urinary retention
3) fecal impaction
4) bleeding
5) infection
6) long term sequelae :
a. inconteninece
b. anal stenosis

Question 15

Anal fissure=

Answer 15

Tear in the andoderm distal to the dentate line

• symptoms: tearing pain with defecation and hematochezia , pts are often too tender to tolerate DRE, anoscopy or proctoscopy
• acute fissure always heal with medical management
• chronic fissures develop ulcerationsl and heaped up edges , may require surgery

Question 16

Treatment of anal fissure :

Answer 16

1) dietary changes : bulk agents, stool softeners and warm sitz bath
2) topical agents: lidocaine jelly or analgesic creams , nitroglycerin ointment , oral and topical diltiazem and topical nefidipine
3) botulinum toxin
4) surgical sphincterectomy for chronic fissures that failed medical therapy

Question 17

Anorectal sepsis and cryptoglandular abscess:

Answer 17

Infection of an anal gland in the intersphincteric space -formation of an abscess that enlarges and spreads along one of several planes in the perianal and perirectal space

Question 18

Diagnosis of anorectal sepsis and abscess:

Answer 18

▪️pain is the most common complaint
A palpable mass often is detected by DRE
▪️occasionally, pts will present with fever , urinary retention or sepsis
▪️the diagnosis of a perianal or ischiorectal abdcess can be made by physical exam only

Question 19

Treatment of anorectal sepsis and abscess:

Answer 19

✅drainage as soon as the diagnosis is established
*antibiotics are only indicated if there is an extensive cellulitis or pt is immuno compromised, has DM or valvular disease
✅surgical treatment based on the location of abscess

Question 20

Parks classification:

Defining 4 major types of anorectal fistulas

Answer 20

Type1: intermuscular (70%)- between enternal and external sphincters
Type2: trans sphincteric (23%) through the external sphincter into the ischiorectal fossa
Type3: extrasphincteric(5%) from rectum to skin
Type 4: suprasphincteric(2%)

Question 21

Imaging studies for anal fistulas:

Answer 21

▪️fistulography
▪️endoanal/endorectal ultrasound 
▪️MRI
▪️CT
▪️Barium enema/ small bowel series

Question 22

Diagnostic procedures of anal fistulas:

Answer 22

Examination of the perineum, DRE, anoscopy are performed after anesthesia
Proctosigmoidoscopy/ clonoscopy

Question 23

Treatment of anal fistulas :

Answer 23

✅fistulotomy/ fistulectomy
✅seton placement (cutting or no cutting seton)
✅fibrin glue has been used to treat persistent fistulas with variable results

Question 24

Rectal prolapse:

Answer 24

Is a protrusion of the full thickness of the rectum through the anus
▪️cuases: colonic inssusception or sliding hernia,increased intra abdominal pressure , seen more common in elderly

Question 25

Clinical presentation of rectal prolapse:

Answer 25

Pt complains of prolapse , rectal bleeding , discharge.

Question 26

Treatment of rectal prolapse:

Answer 26

✅surgical treatment combines of bowel resection and rectal fixation.

1) ant. Resection and suture fixation
2) the ripstein procedure
3) the thiersch loop

Question 27

Anal cancer risk factors :

Answer 27

🔸95% associated with HPV
-human papilloma virus , papovavirus
-most common viral sexually transmitted disease
🔸HPV( high risk serotypes : hpv16 and 18 )

Question 28

Prevention and screening for anal cancer :

Answer 28

🔸vaccination: recombinant HPV Quadrivalent vaccine (HPV4)
🔸screening method :
-physical examination : anal exam ,DRE, anoscopy
-anal pap smear
-high resolution anoscopy

Question 29

Anal lesions :

Perianal lesions :

Answer 29

🔸Lesions that are not visible or are incompletely visible

🔸lesions that are completely visible

Question 30

Treatment of anal cancer:

Answer 30

HPV Dysplasia : 
-LSIL= low grade condyloma
-HSIS=high grade =carcinoma in situ 
✅topical treatments: 
-podofilox 0.5% gel 
-Imiquimod 
-Trichloracetic acid 
✅surgical method: 
-excision
-cryotherapy
-fulguration
-electrodesication