Perianal Surgery Flashcards Preview

Medicine Finals - Imperial & Quick Medical Revision > Perianal Surgery > Flashcards

Flashcards in Perianal Surgery Deck (61)
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1
Q

What is the anatomy of the rectum?

A
  • 12cm
  • Sacral promontory to levator ani muscles
  • The 3 tenia coli fuse around the rectum to form a
    continuous muscle layer
2
Q

What is the anatomy of the anal canal?

A
  • 4cm
  • Levator ani muscle to anal verge
  • Upper 2/3 of canal
    Lined by columnar epithelium
    Insensate
    Superior rectal artery and veni
    Internal iliac nodes
- Lower 1/3 canal 
Lined by squamous epithelium 
Sensate 
Middle and inf rectal arteries and veins 
Superficial inguinal nodes 

Dentate line = squamomucosal junction
White line = where anal canal becomes true skin.

3
Q

What are the anal sphincters

A

Internal - thickening of rectal smooth muscle. Involuntary control.

External: Three rings of skeletal muscle

  • Deep
  • Superficial
  • Subcut

Under voluntary control

  • Anorectal ring - Deep segment of external sphincter which is continuous with puboretalis muscle (part of levator ani)
  • Palpable on PR ~5cm from the anus
  • Demarcates junction between anal canal and rectum
  • Must be preserved to maintain continence.
4
Q

What is a perianal haematoma?

A

Subcut bleeding from a burst venule caused by straining or the passage of hard stool
Also called an external pile.

Presents

  • tender blue lump at the anal margin
  • Pain worsened by defecation or movement

Management

  • Analgesia + Spontaneous resolution
  • Evacuation under LA
5
Q

What is proctalgia fugax?

A

Young, anxious man
Crampy anorectal pain worse @ night.
Unrelated to defection
Associated with trigeminal neuralgia

Reassurance
GTN cream

6
Q

Perineal warts?

A

SEen in MSM
Condylomata accuminata
- HPV
- Manage: podophyllin pain, cryo, surgical excision

  • Condylomata lata
    Syphilis
  • Manage: penicillin
7
Q

What is pruritis ani caused by?

A
50% idiopathic
Poor hygiene 
Haemorrhoid 
Anal fissure
Anal fistula 
Fungi, worms 
Crohns 
Neoplasia
8
Q

What are haemorrhoids?

A

Disrupted and dilated anal cushions

Pathophysiology
- Anal cushion: mass of spongy vascular tissue
- Positioned @ 3, 7, 11 O-clock.
Where the three major arteries that feed the vascular plexuses enter the anal canal.

Gravity, straining –> engorgement and enlargement of anal cushions.

Hard stool disrupts connective tissue around cushions

  • Cushions protrude and can be damaged by hard stool
  • -> bright red (capillary bleeding)
  • Haemorrhoid arise above dentate line so not painful.

May ulcerate if gripped by anal sphincter.

9
Q

Causes of haemorrhoids?

A
Constipation with prolonged straining 
Venous congestion may contribute 
- Pregnancy 
- Abdominal tumour 
- Portal HTN
10
Q

Classifications of haemorrhoids?

A

1st degree: never prolapsed
2nd degree: prolapse on defection but spontaneously reduce
3rd: prolapse on defecation but require digital reduction
4th: remain permanently prolapsed.

11
Q

Symptoms of haemorrhoids?

A

Fresh painles PR bleeding

  • Bright red
  • On paper, on stool, may drip into pan
  • Pruritis ani
  • Lump in perianal area
  • Severe pain = thrombosis
12
Q

Examination of haemorrhoids?

A
  • Full abdo exam, palpating for masses
  • Inspect perianal area: masses, rectal bleeding
  • DRE: can’t palpate piles unless thrombosed
    rigid sig to identify higher rectal pathology
  • Proctoscopy (also allows Rx)
13
Q

Differential for haemorrhoids?

A

Perianal haematoma
Fissure
Abscess
Tumour

14
Q

Management of haemorrhoids?

A

Conservative

  • Increased fibre and fluid intake
  • Stop straining at stool
15
Q

Medical management of haemorrhoids?

A

Topical preparations

  • Anusol: hydrocortisone
  • topical analgesics

Laxatives: lactulose, Fybogel

16
Q

Intervention of haemorrhoids?

A

Injection with sclerosant 0 5% phenol in Almond oil
- above dentate line. Can cause impotence and prostatitis.

Barron’s banding –> thrombosis and separation. Superior to injection sclerotherapy.
- SE: bleeding, infection

Cryotherapy
- SE: watery discharge post-procedure

Infra-red coagulation

17
Q

What are the surgical options for haemorrhoids?

A
  • Excision of piles + ligation of vascular pedicles
  • Lactulose + metronidazole 11 week pre-op
  • Discharge with laxatives post-op
  • SE: bleeding, stenosis.
18
Q

How do you manage thrombosed piles?

A

Significant pain, examination reveals a purplish oedematous, tender subcut perianal mass.

If patient presents within 72hrs then referral should be considered for excision.

  • Analgesia
  • Ice-packs
  • Stool softener
  • Bed rest with elevated foot of bed
  • Pain usually resolves in 2-3 weeks
  • Haemorrhoidectomy is not usually necessary.
19
Q

What is an anal fissure?

A

Tear of squamous epithelial lining in lower anal canal

20
Q

Causes of anal fissure?

A

Mostly trauma 2ndry to passage of hard stool

  • associated with constipation
  • Spasm of internal anal sphincter contributes to pain and –> ischaemia + poor healing.
  • Commoner in women
21
Q

Rare causes of anal tissue?

A

Multiple + lateral fissures
- Crohns
- Herpes
Anal Ca

22
Q

Presentation of anal fissure?

A

Intense anal pain

  • Especially on defecation
  • may prevent pt from passing stools
  • Fresh rectal bleeding
    On paper mostly.
23
Q

Examination of anal fissure?

A

PR often impossible
Midline ulcer is seen
- Usually posterior @ 6 O’clock
- may be anterior

May be mucosal tag –> Sentinel pile (usually posterior @ 6 oclock)

Groin LNs suggest complicating factor: e.g HIV.

24
Q

Management of anal fissure?

A

If fissure recurrent, chronic or difficult to manage the patient required EUA.

25
Q

Conservative management of anal fissure?

A

Soaks in warm bath
Toileting advice
Dietary advice: increased fibre and fluids

26
Q

Medical management of anal fissure?

A

Laxatives: lactulose + fybgel
Topical –> resolution in 75%
- Lignocaine

For chronic anal fissure (>6 weeks)

  • GTN
  • Diltiazem

if topical GTN is not effective after 8 week refer to consider surgery or
Botulinum injection

27
Q

Surgical management of anal fissure?

A

Division of internal anal sphincter @ 3 o’clock
Pre-op anorectal US + mannometry

= Sphincterotomy

Complications

  • Minor faecal/flatus incontinence
  • Perianal abscess
28
Q

What is a fistula in ano?

A
  • Abnormal connection between ano-rectal canal and skin.
29
Q

What is the pathogenesis of fistula in ano?

A

Occur 2ndry to perianal sepsis

  • Blockage of intramuscular glands –> abscess
  • Abscess discharges to form

Associated with

  • Crohns
  • Diverticular disease
  • Rectal Ca
  • Immunosuppression
30
Q

Classifications of fistula in ano?

A

high: cross sphincter muscles above dentate line
Low: Don’t cross sphincter muscles above dentate line

31
Q

What is Goodsall’s rule?

A

Determins path of fistula tract

  • Fistula anterior to anus tracks in a straight line.
  • Fistula postioer to anus will always have internal opening at the 6 o-clock position –> curved trck.
32
Q

Presentation of fistula?

A

Persistent anal discharge

Perianal pain or discomfort

33
Q

Examination of fistula?

A

May visualise external opening: may be pus

Induration around the fistula on DRE

Proctoscopy may reveal internal opening.

34
Q

Investigations of fistula?

A

MRI

Endoanal US

35
Q

Management of fistula?

A

Extent of fistula must first be delineated by probing fistula EUA?

36
Q

LOw fistula?

A

Fistulotomy and excision

- Laid open to heal by 2nd intention.

37
Q

High fistula ?

A
  • Fistulotomy could damage the anorectal ring
  • Suture - a seton - passed through fistula and gradually tightened over months.
  • Stimulates fibrosis of tract
  • Scar tissue hold sphincter together.
38
Q

What is peri-anal sepsis/Abscess?

A

Anal gland blockage –> infection –> abscess
E.g coli, bacterioids. Staph A

May develop from skin infections
- E.g sebaceous gland or hair follicle

39
Q

Associations of anal absces?

A
Perianal: 45% 
- Discrete local red swelling close to anal verge
- Ischiorectal: <30% 
Systemic upset 
Extermely painful on DRe
  • Interspincteric/intermuscular: >20%
  • Pelvirectal/supralevator: ~5%
    Systemic upset
    Bladder irritation

Diabetes/malignancy associated.

40
Q

Presentation + examination of anal abscess?

A

Throbbing perianal pain
- Worse on sitting

Occassionally a purulent anal discharge

Spiking fever/temperature

Perianal mass or cellulitic area
Fluctuant mass on PR
Septic signs, fever, tachycardia

41
Q

Management of perianal abscess /

A

ABx may suffice if management instigated v.early in course.

Most cases require EUA with I+D. (incision and draining)

  • Wound packed
  • heals by 2nd intention
  • Daily dressing for 7-10 days.

Look for an anal fistula which complicates ~30% of abscess.

42
Q

What is a pilonidal sinus?

A

Definition -

  • Pilonidal - nest of hair
  • Sinus: blind ending tract, lined by epithelial or granulation tissue. Opens an epithelial surface.
43
Q

How does a pilonidal sinus form?

A

Hair works its way benath skin –> foreigh body reaction –> formation of abscess.

Usually occur in the natal cleft.

44
Q

Risk factors of pilonidal sinus

A

M>F = 4:1
- geo: Mediterranean, middle east, asian

  • Often overweight with poor personal hygiene
  • Occupations with lots of sitting: e,g truck drivers
45
Q

Presentation of pilonidal sinus?

A

Persistent discharge or purulent or clear fluid

Recurrent pain

Abscesses

46
Q

Management of pilonidal sinus?

A

Conservative

  • Hygiene advice
  • Shave/remove hair from affected areas
Surgical 
- Incision + drainage of abscesses
- Elective sinus excision 
Methylene blue to outline tract 
Recurrence in 4-15%.
47
Q

Anal carcinoma?

A

Uncommon: 250-300 cases yr in the UK.

Pathology
- 80% - SCC (also melanoms, adenocarcinomas)

Anal margin tumours

  • Well differentiated keratinising lesions
  • Commoner in men
  • Good prognosis

Anal canal tumour

  • Arise above dentate line
  • Poorly differentiated, non-keratinising
  • Commoner in women
  • Poor prognosis

Spread

  • Above dentate line –> Internal iliac nodes
  • Below dentate line –> inguinal nodes
48
Q

Aetiology of anal carcinoma?

A
HPV (16,18, 31, 33) is important factor 
- Most important. 
- Increased incidence in MSM
 Increased incidence if perianal warts.
- Smoking is also a risk factor
- IMmunosupression
49
Q

Presentation of anal carcinoma?

A
  • Perianal pain and bleeding
  • Pruritus ani
  • Faecal incontinence
  • -> 70% have sphincter involvement @ presentation
  • May have rectovaginal fistula

Palpable lesion in only 25%
± palpable inguinal nodes

50
Q

Investigations for anal carcinoma?

A

Low Hb
Endoanal US
Rectal EUA + biopsy
CT/MRI: assess pelvic spread

51
Q

Management of anal carcinoma?

A

Chemoradiotherapy: Most pts
- 50% 5yrs

Surgery
- Reserved for:
Tumours that fail to respond to radiotherapy

GI obstruction

Small anal margin tumours without sphincter involvement.

52
Q

What is rectal prolapse?

A

Protrusion of rectal tissue through anal canal

53
Q

Type 1 prolapse?

A

Mucosal prolapse

  • Partial prolapse of redundant mucosa
  • Common in children esp with CF.
54
Q

Type 2 prolapse?

A

Full thickness

  • Commoner compared to Type 1
  • Usually elderly females with poor O+G History
55
Q

Presentation of rectal prolapse?

A
  • Mass extrudes from rectum on defection
  • May reduce spontaneously or require manual reduction
  • May become oedematous and ulcerated –> pain and bleeding
  • Faecal soiling
  • Associated with vaginal prolapse and urinary incontinence
56
Q

Examination of rectal prolapse?

A

Visible prolapse: brought out on straining
± excoriation and ulceration
Decreased sphincter tone on PR
Associated with uterovaginal prolapse

57
Q

Investigations or rectal prolapse?

A

Sigmoidoscopy to exclude proximal lesions
Anal manometry
Endoanal US
MRI

58
Q

Management of prolapse?

A

Partial prolapse
- Phenol injection
- Rubber band ligation
Surgery: delorme’s Procedure

Complete Prolapse
- conservative
PElvic floor exercises
Stool softeners

59
Q

Surgery of prolapse?

A

Abdominal approach: rectopexy

  • Lap or open
  • Mobilise rectum fixed to sacrum with mesh

Perineal approach
- Delorme’s procedure
Resect mucosa and suture the two mucosal boundaries
- Almeirs procedure resects the colon via the perineal route.

60
Q

Rectal intussceception

A

Typically presents with with symptoms of obstructed defecation.

Pathology is best demonstrated by defecating proctogram rather than barium enema.

61
Q

Solitary rectal ulcer?

A

Associated with chronic straining and constipation

Histology shows mucosal thickening, lamina propria replaced with collagen and smooth muscle.

Diagnostic work up should include endoscopy and probably defacting proctogram.