RECTUS, ANUS, PERINEUM: 94

Question 1

origin of caudal and middle rectal artery

Answer 1

internal pudendal artery (from internal iliac)

Question 2

muscle type of internal and external anal sphincter

Answer 2

internal: smooth muscle, involuntary function
external: circular band of striated muscle

Question 3

nervous system of the rectum

Answer 3

intrinsic system: enteric nervous system

extrinsic: parasympathetic nerves

Question 4

use of antibiotics as a prophylactic therapy before colonic and rectal surgery

Answer 4

different opinion and outcomes. seems like it is recommended to reduce post.op surgical site infection

Question 5

timing of antibiotic administration before surgery

Answer 5

6-60 min before surgical incision, greatest reduction in surgical site infection

Question 6

possible approach to the rectum

Answer 6

ventral
dorsal
lateral
caudal

Question 7

when is recommended a ventral approach to the rectum?

Answer 7

cranial rectum and colo-rectal junction

Question 8

possibility of sacroiliac luxation after pelvic symphysiotomy and abaxial retraction of the hemipelvis?

Answer 8

25% retraction (25-35 kg) of sacral width did not result in luxation (1-1,7 cm gap)

50-70% retraction usually determine unilateral sacroiliac luxation

Question 9

when is recommended dorsal approach to the rectum

Answer 9

caudal to mid rectum

Question 10

dorsal rectum surgical approach

Answer 10

after incision and fat dissection can see

retrococcygeus muscle
dorsal surface rectum
external anal sphincter

setrococcygeus can be transected near ventral attachments to coccygeal vertebrae

blunt dissection between elevator ani and ext anal sphincter

Question 11

different techniques for caudal approach to the rectum

Answer 11

rectal eversion: prolapse of the rectum to approach small lesions

transcutaneous rectal pull-through procedure: skin incision adjacent to anal opening. retrococcygeus muscle is transected

transanal rectal pull-through procedure: incision made 1-2 cm cranial (inside) the anocutaneous junction

combined abdominal-transanal approach

Question 12

how many anatomic types exists for atresia ani?

Answer 12

1: concenital stenosis

2, 3, 4: varying degrees of rectal agenesis along with anal abnormalities

Question 13

clinical signs of patients with rectovaginal or urethrorectal fistulas

Answer 13

vulvar or perianal inflammation 
dysuria
hematuria
pollakiuria
chronic or recurrent urinary tract infection 
tenesmus
diarrhea
megacolon

Question 14

what is an anogenital cleft?

Answer 14

feces and urines entrar the same common cavity and body opening (cloaca)

Question 15

how to differentiate rectal prolapse from rectal prolapsed intussusception

Answer 15

pass an instrument beetwen prolapse and anus: if it do not pass is a prolapse

Question 16

therapy for rectal prolapse

Answer 16

topical 50% dextrose
systemic furosemide

gentle pressure to reintroduce

nonadsorbable monofilament purse string suture

fed low residue diet and laxatives such as lactulose

Question 17

3 most common perianal tumors

Answer 17

circumanal gland adenoma, adenocarcinoma. anal sac adenocarcinoma

Question 18

perianal adenomas are hormone dependent?

Answer 18

yes: stimulated by androgens and inhibited by estrogens. in femal occurs more frequently in spayed bitches.

Question 19

perianal epithelial tumors in cats?

Answer 19

described but not clear if are really hepatoid gland tumors

Question 20

% of success for treatement

Answer 20

90% in male dogs if excision and castration is performed

10% of dogs also develop testicular tumors, especially if concurrent perineal hernia

Question 21

are perianal adenocarcinoma hormone dependent?

Answer 21

it seems not, but it is recommended castration

Question 22

classification for perianal adenocarcinoma

Answer 22

T1: <2cm
T2: 2-5 cm
T3: > 5 cm or invasive
T4: invasive

Question 23

difference beetween adenocarcinoma of rectum and small intestine

Answer 23

small int andenocarcinoma has a more malignant behavoiur

Question 24

3 most common deseases of anal sac

Answer 24

impaction
abscessation
sacculitis

Question 25

use of cox2 inhibitors for treatement of anal sac adenocarcinoma

Answer 25

100% AS adenocarcinoma reported expression of cox2

Question 26

incidence of pseudohyperparatiroidism in anal sac adenocarcinoma

Answer 26

20-90%

Question 27

most common syte of metastasi for AS adenocarcinoma

Answer 27

sub lumbar lymphnodes

Question 28

is hypercalcemia common in cats with AS adenocarcinoma?

Answer 28

not very common neoplasia. hypercalcemia is rarely a feature

Question 29

pros and cons of open vs closed anal sacculactomy technique

Answer 29

open:
P: permits visualization of secretory lining. better visualization, sure removal
C: trauma to ext anal sphincter, post.op infection, tumor dissemination

more complication seen with the traditional open technique

Question 30

possible complication after surgery for perineal fistulas

Answer 30

success rates 51-83%
recurrence rates 13-56%
fecal incontinence 13-29%

fecal incontinence due to damage to the caudal rectal nerve and ext anal sphincter (20-33%)

Question 31

perineal hernia: name the muscles that composes the pelvic diaphragm

Answer 31

sphincter ani externus muscle
elevator ani muscle
coccygeus muscle

med to lat

Question 32

most common localization for perineal hernia

Answer 32

beetween elev. ani, int. obturator, ext anal sphincter (CAUDAL HERNIA)

Question 33

name other localization of perineal hernia

Answer 33

DORSOLATERAL: coccygeus-levator ani
VENTRAL: ischiouretralis, bulbocavernosus, ischiocavernosus
LATERAL: coccygeus, sacrotuberous ligament

Question 34

incidence of testicular neoplasia in dogs with perineal hernia

Answer 34

up to 69.7%

Question 35

incidence of bladder retroflexion in perineal hernia

Answer 35

20-29%