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ANAL AND PERIANAL REGION 11
S u g g e S t e d R e a d i n g
Bollard RC, Gardiner A, Lindows S, etal. Normal female anal sphincter. Dif-
culties in interpretation explained. Dis Colon Rectum. 2002;45:171–175.
Canessa CE, Miegge LM, Bado J, etal. Anatomic study of lateral pelvic lymph
nodes: implications in the treatment of rectal cancer. Dis Colon Rectum.
2004;47:297–303.
Carty NJ, Moran B, Johnson CD. Anorectal physiology measurements are of
no value in clinical practice. True or false? Ann R Coll Surg Engl. 1994;76:
276–280.
Church JM, Raudkivi PJ, Hill GL. e surgical anatomy of the rectum—a
review with particular relevance to the hazards of rectal mobilization.
Int J Colorectal Dis. 1987;2:158–166.
Goligher JC. e blood supply to the sigmoid colon and rectum. Br J Surg.
1949;37:157–162.
Gordon PH, Nivatvongs S. Principles and Practice of Surgery for the Colon,
Rectum and Anus. 3rd ed. New York: Informa Healthcare USA; 2007.
Havenga K, De Ruiter MC, Enker WE, Welvaart K. Anatomical basis of au-
tonomic nerve-preserving total mesorectal excision for rectal cancer.
Br J Surg. 1996;83:384–388.
Heald RJ, Meran BJ. Embryology and anatomy of the rectum. Semin Surg On-
col. 1998;15:66–71.
Lubowski DZ, Meagher AP, Smart RC, Butler SP. Scintigraphic assessment
of colonic function during defecation. Int J Colorectal Dis. 1995;10:91–93.
Matzel KE, Schmidt RA, Tangho EA. Neuroanatomy of the striated muscular
and anal mechanism. Implications for the use of neurostimulation. Dis
Colon Rectum. 1990;33:666–673.
Miscusi G, Masoni L, Dell’Anna A, Montori A. Normal lymphatic drainage of
the rectum and the anal canal revealed by lymphoscintigraphy. Coloproc-
tology. 1987;9:171–174.
Yamaguchi S, Kuroyanagi H, Milson JW, Sim R, Shimada H. Venous anatomy
of the right colon. Precise structure of the major veins and gastrocolic
trunk in 58 cadavers. Dis Colon Rectum. 2002;45:1337–1340.
H
Anthony J. Senagore
emorrhoids are vascular cushions that lie close to the anus and
H
are subject to the stresses and strains of defecation. ey are
normal structures that become symptomatic when thrombosis or
prolapse develops as a result of either a congenital weakness in the
area or because of excessive or repeated straining. e challenges of
managing patients with symptomatic hemorrhoids include making
a correct diagnosis, persuading patients to improve their defecatory
habits, and using the appropriate procedure to manage the problem
at hand. In this chapter, external and internal hemorrhoids will be
considered separately.
EXTERNAL HEMORRHOIDS
e external hemorrhoidal plexus is a network of veins that run
around the anus at the anal verge. e veins become symptomatic
when they thrombose. Resolution of external hemorrhoid thrombosis may predispose to anal tags that are usually asymptomatic but
are typically excised along with prolapsing internal hemorrhoids.
Acute thrombosis of the external hemorrhoidal plexus is a painful
condition that tends to follow straining, either during liing, childbirth, or defecation. Aected patients are in considerable pain and
have an edematous lump at the anal verge caused by the clot. Oen
the blue color of the clot conrms the diagnosis. Surgical excision
of acutely thrombosed external hemorrhoids is warranted when the
thrombosis is large, painful, and identied within 72 hours of onset.
Sometimes the clot ulcerates through the skin and patients experience anal bleeding independent of bowel habits, with partial easing
of the pain. is presentation is another indication for surgery. Small
external hemorrhoidal thromboses are easily managed in the oce
setting with a local anesthetic and complete excision of the clot and
vein, with or without skin closure. More extensive thromboses should
be excised with use of a general anesthetic to allow careful planning
of the excision and preservation of the anoderm.
ANATOMY AND ETIOLOGY OF
INTERNAL HEMORRHOIDS
Internal hemorrhoids are vascular cushions lying above the dentate
line under the mucosa of the low rectum. e classic orientation of
the hemorrhoidal cushions is right anterior, right posterior, and le
lateral, although intervening secondary hemorrhoidal complexes may
blur this classic anatomy. e arterial blood supply, which contributes
to the frequent symptom of bright red rectal bleeding, is derived from
the superior rectal artery, a branch of the inferior mesenteric artery,
the middle rectal arteries arising from the internal iliac arteries, and
the inferior rectal arteries arising from the pudendal arteries. Above
the dentate line the venous drainage enters the portal venous system,
whereas below the dentate line it passes to the systemic venous system. is vascular anatomy creates the cushions that contribute to
12
anal continence and can be damaged by excessive straining, leading
to the prolapse and bleeding typical of symptomatic hemorrhoids.
An understanding of the stages of hemorrhoidal pathophysiology
is the basis for developing a strategy for management of symptomatic
hemorrhoids. e staging system is shown in Box 2-1. At the earliest
stage of disease, transudation of blood through thin-walled, damaged
veins and/or arterioles presents primarily as painless bleeding and
can be managed with astringents or local ablation of the vessels. Later,
as the damage progresses to signicant disruption of the mucosal suspensory ligament, a technique capable of relocating the prolapsing
tissue to its normal location and xing the tissue at that location will
be required.
CLINICAL EVALUATION
e typical constellation of hemorrhoidal symptoms includes bleeding, protrusion, and pain. However, only about one third of all
patients with anorectal symptoms will actually have hemorrhoids as
the cause of their symptoms. Hemorrhoidal bleeding, which typically
occurs aer bowel movements, is painless and visible as bright red
blood either on the toilet paper or in the commode. e bleeding
can become more severe as the hemorrhoids enlarge and are either
partially or completely trapped in a prolapsed position. Patients with
tight internal sphincters are prone to magnied hemorrhoidal symptoms because of the increased pressure in the anus. e history then
addresses bowel habits, the frequency of straining upon defecation,
recent changes in medications, diet, or lifestyle, and the presence
of a family history of colorectal cancer. e patient should be asked
about prior procedures performed to treat hemorrhoids, although
the answer must be taken with a grain of salt unless it is supported by
medical records.
Examination of the patient with hematochezia, although tailored
by the age of the patient, should include sucient investigations to
rule out a proximal source of bleeding such as inammatory bowel
disease or neoplasia. Hemorrhoids should not be accepted as the
cause of iron deciency anemia because this cause is rare.
First, a careful digital examination of the anal canal and distal
rectum should be performed, including palpation of the prostate in
men. Inspection of the anus may reveal skin tags, bulging external
hemorrhoidal cushions (clues to the presence of internal hemorrhoidal prolapse), or fourth-degree internal hemorrhoids. Other
conditions may be present that mimic or co-exist with hemorrhoids,
such as anal excoriation, anal neoplasms, condylomata, or ssure.
If the patient does not have a ssure, an anoscopy is performed to
determine the size and degree of prolapse of the hemorrhoids. Poking the cushions with a cotton-tipped swab gives an impression of
the degree of redundancy and the suitability of the hemorrhoid for
elastic band ligation. White plaques on the hemorrhoids (pseudoepitheliomatous hyperplasia) are an indication of chronic prolapse.
Hemorrhoids should be classied as previously described to dene
ANAL AND PERIANAL REGION 13
BOX 2-1: The Standard Classification for Internal
Hemorrhoidal Diseases
Grade I = bleeding
Grade II = protrusion with spontaneous reduction
Grade III = protrusion requiring manual reduction
Grade IV = irreducible protrusion of hemorrhoidal tissue
the degree of mucosal irritation, prolapse, columns involved, and
associated anal skin tags. If the patient has presented with bleeding,
has an increased risk for colorectal cancer, or is at average risk but is
overdue for screening, a colonoscopy is requested. No physical treatment should be performed without clearing the colon, because drop
metastases from a cancer proximal to an anal canal wound can occur.
NONEXCISIONAL OPTIONS
Medical Management
Many patients with symptomatic hemorrhoids strain during defecation for several reasons. If the straining is due to small-volume
stools, they need more roughage in their diet. If the straining is due
to hard stools, they need more roughage and perhaps a properistaltic
agent such as prune juice. If the straining occurs because defecation
is deferred, they need to respond to the urge to defecate when it is
rst perceived and not shut it down. An analysis of defecation and
dietary habits and correction of problematic habits with the aim of
avoiding straining may eliminate symptoms and allow patients to
avoid a procedure. Correction of problematic habits is important
in all patients, however, because straining aer banding and aer a
hemorrhoidectomy may lead to recurrent symptoms. In at least 50%
of patients, symptomatic internal hemorrhoids can be successfully
managed by improving bowel habits.
Sclerotherapy
Sclerotherapy of symptomatic internal hemorrhoidal disease has
been performed since the nineteenth century and remains a highly
eective, low-risk means of managing stage I hemorrhoids. Treatment produces local tissue destruction, which simultaneously ablates
small vessels in the submucosa and creates tissue xation and atrophy
of the hemorrhoidal complex. e sclerosing agents most commonly
used are sodium morrhuate and sodium tetradecyl sulfate. Briey,
the procedure involves anoscopic identication of the hemorrhoidal
complex followed by instillation of the sclerosant into the submucosa
above the level of the dentate line using a 25-gauge spinal needle.
Typically, 1 to 2 mL of sclerosant per location is adequate, and multiple locations can be treated during a single session.
Energy-Based Destruction
the cost to acquire the machines and cleaning requirements between
procedures should be considered.
Hemorrhoidal Ligation with Rubber Bands
In 1963, Barron became the rst person to describe treatment of
hemorrhoids with rubber bands. is technique has withstood the
test of time, with multiple large-scale studies documenting both
safety and ecacy, and it is a good option for grade II and III internal
hemorrhoids. When the bands are applied correctly, pain is minimal
both during and aer the procedure.
Banding is best performed with the patient in a prone jackknife
position. Anoscopy is performed to assess the degree of hemorrhoidal
prolapse and to establish the sites of the worst and the least prolapse.
A set of two bands is applied above the dentate line at the top of the
hemorrhoidal column by pulling the prolapsing tissue into the applicator. An assistant is needed to hold the anoscope and may help by
slightly easing it out when the hemorrhoid is pulled or sucked into
the applier. e worst aected hemorrhoid is treated rst, followed
by the next worst aected hemorrhoid. It is wise to place a maximum
of three sets of bands at once because discomfort due to the tightness can become severe. Patients are warned to expect to feel an urge
to defecate aer banding that may be quite uncomfortable and will
last the remainder of the day. Some patients may experience vasovagal symptoms aer banding and thus patients should be asked to lie
down for 10 minutes aer the procedure.
Discomfort immediately aer band placement may be reduced
with the injection of a local anesthetic agent; however, this injection
does not appear to provide a long-lasting benet. Banding is associated with hemorrhage from the ulcers that occur at the band sites.
is outcome is uncommon but can occur within the rst 2 weeks of
the procedure; it seems to be more likely if a large amount of tissue is
pulled into the band. e presence of acute pain aer banding means
that the bands have been applied too low and sensory epithelium
has been included in the band, in which case the bands should be
removed. Finally, a rare but potentially fatal complication of perineal sepsis can occur, which is heralded by the symptoms of increasing rectal pain, fever, and the inability to void urine. It is essential
to evaluate patients with these symptoms early and to treat them
aggressively with broad-spectrum antibiotics and aggressive surgical
drainage. e full eect of the bands is not noted for a month, by
which time the ulcers at the sites of the band application have healed
and scarring has occurred.
Bayer and colleagues reported a series of 2934 patients who
underwent elastic band treatment of internal hemorrhoids, with 79%
experiencing complete relief of symptoms aer a single session with
treatment of only one or two locations. Multiple sessions were needed
as follows: 2 sessions, 32%; 3 sessions, 17%; 4 sessions, 25%; and 5
sessions, 20%. Although the need for multiple sessions is a negative
aspect of this technique, only 2.1% of patients required an excisional
hemorrhoidectomy. Banding oers sustained, inexpensive relief of
symptoms, with 69% of patients maintaining long-term relief and
only 7.5% ultimately requiring an excisional hemorrhoidectomy.
Bipolar diathermy converts electrical current into heat energy to
coagulate the hemorrhoidal tissue, including the mucosa and submucosa. e machine generates a 2-second pulse of energy to
accomplish the treatment. e technique produces the same basic
eect as sclerotherapy, and therefore the indications for treatment are
very similar. Other energy-based options include infrared coagulation and therapy with direct current (Ultroid; Ultroid Technologies,
Inc., Tampa, Fla.). Infrared coagulation employs a tungsten halogen
lamp that generates heat energy, generally for a 1.5-second period at
a depth of penetration of 3 mm. Direct-current therapy uses electrical current applied for up to 10 minutes per complex treated. ere
is probably no advantage of one technique over the other, although
EXCISIONAL HEMORRHOIDECTOMY
An excisional hemorrhoidectomy is indicated when the degree of
prolapse of the internal hemorrhoids is too great to allow eective
banding—that is, the bands themselves would ride up and down on
the prolapsing hemorrhoids and would be too far away from the submucosa to x the mucosa. Surgery eectively corrects the associated
prolapse, bleeding, discomfort, anal seepage, and diculties with
anal hygiene. Excisional hemorrhoidectomy is the only option for
gangrenous internal hemorrhoids.
Several techniques have been described for excisional hemorrhoidectomy, including the Milligan-Morgan technique, the
HemorrHoids14
Ferguson closed hemorrhoidectomy, the Whitehead hemorrhoidectomy, and the more recently described stapled hemorrhoidectomy
(or stapled hemorrhoidopexy). e procedures are usually performed in the operating theater aer minimal preoperative preparation of the bowel, and excision can be performed with or without
energy devices. e use of lasers for excisional hemorrhoidectomy
oers no advantage and in fact causes delayed healing, increased
pain, and increased cost.
e anesthesiologist and patient usually decide which type of
anesthetic will be used; however, a local anesthetic supplemented by
the administration of intravenous narcotics and propofol is highly
eective and short acting. e use of spinal anesthesia, although eective, may increase the risk of postoperative urinary retention because
of a higher intraoperative administration of intravenous uids.
e Milligan-Morgan hemorrhoidectomy, which is widely
practiced and described in Europe, includes resection of the entire
enlarged internal hemorrhoid complex, ligation of the arterial pedicle, and preservation of intervening anoderm. e incision in the
anal canal and perianal skin is le open.
e closed Ferguson hemorrhoidectomy oers the benet of primary wound closure with similar safety and ecacy. e following
technical tips are related to the procedure: the entire internal/external
hemorrhoidal complex should be removed with an hourglass-shaped
excision (centered at the mid portion of the anoderm) with limited
anoderm removal; the internal and external anal sphincters should
be preserved; and primary closure of the entire wound should be performed. Occasionally it is necessary to undermine aps of anoderm
and perianal skin to allow removal of intermediate hemorrhoidal tissue while preserving the bridges of anoderm between pedicles.
e Whitehead hemorrhoidectomy was devised to eradicate
the enlarged internal hemorrhoidal tissue circumferentially with
advancement of the prolapsed dentate line proximally to reconstruct
the anal canal lining. is technique has been largely abandoned
because of the high rates of mucosal ectropion and anal stricture
resulting from the complexity of reconstruction.
Instrumentation for Excisional Hemmorrhoidectomy
e increasingly critical emphasis on cost-eectiveness requires a
thoughtful assessment of the need for advanced instrumentation in
hemorrhoidectomy. e ecacy of conventional surgery is unquestioned, whereas the benets of considerably more expensive energy
devices are mostly theoretical. Standard monopolar electrocautery is
relatively inexpensive and can be useful to control nuisance bleeding from the wound edges and small vessels. Suture ligation of the
main pedicle is still required, and thermal spread is associated with
increased pain.
Laser technology has been evaluated both as a means of cutting
hemorrhoidal tissue and as a technique for ablation, but it is simply
another way of causing tissue destruction. Although some authors
have suggested that patients experience less pain with the use of
Nd:YAG laser for excision and coagulation, a prospective randomized trial demonstrated greater pain and slower healing when compared with sharp dissection.
A bipolar cautery device capable of simultaneous tissue division
and blood vessel coagulation has been compared with monopolar diathermy hemorrhoidectomy, with most of the data suggesting
reductions in operative time and early postoperative pain. A metaanalysis compared hemorrhoidectomy with LigaSure (Medtronic,
Minneapolis, Minn.) to conventional excisional techniques and
found similar cure rates but shorter operative time, decreased pain,
shorter time to wound healing, and less time o from work. A competing technology is the Harmonic scalpel (Ethicon Endo-Surgery,
Cincinnati, Ohio), which relies on a rapidly reciprocating blade to
generate heat for coagulation and tissue transection. Experience with
the Harmonic scalpel suggests low rates of postoperative hemorrhage
(0.6%), urinary retention (2%), ssure (1%), and abscess/stula
(0.8%). Several subsequent prospective, randomized comparisons of
diathermy with the Harmonic scalpel failed to conrm any dierences between the two tools.
PROCEDURE FOR PROLAPSING HEMORRHOIDS (STAPLED HEMMORHOIDOPEXY)
Another option for advanced hemorrhoidal disease is the procedure
for prolapsing hemorrhoids (PPH), which utilizes a circular stapler
to reduce and x the hemorrhoidal complex. e technique entails
placement of a transanal purse-string suture 0.5 cm above the top
of the hemorrhoidal complex to allow partial resection of the rectal
mucosa in the less sensitive distal rectum above the hemorrhoidal
tissue, with repositioning of both the anoderm and hemorrhoidal
columns to the appropriate locations. Prospective randomized trials have been performed to compare this approach with excisional
hemorrhoidectomy, although interest in the United States appears to
be waning. Most of the data support the concept that PPH is associated with a lesser degree of early postoperative pain and a general
reduction in the duration of this pain aer surgery. Giordano and
colleagues addressed the question of long-term outcome for PPH,
demonstrating a signicantly higher rate of prolapse recurrence in
the PPH group and a higher rate of further treatment to correct recurrent prolapses compared with conventional hemorrhoidectomy. An
additional concern associated with PPH is the risk of either closure
of the rectal lumen as a result of failure to place the anvil proximal to
the purse-string suture or sepsis as a result of rectal wall perforation.
ese complications can be life threatening and are dicult to correct
and have reduced interest in the procedure in some circles.
DOPPLER-GUIDED HEMORRHOIDAL DEARTERIALIZATION
A new technique that is gaining popularity is Doppler-guided hemorrhoidal artery ligation, or transanal hemorrhoidal dearterialization
(THD). e Doppler-guided technique provides simultaneous
reduction of the arterial blood ow, reduction of the prolapse (or
mucopexy), and tissue destruction by oversewing the reduced hemorrhoidal tissue. A specically designed proctoscope is used coupled
with a Doppler transducer. At the distal end a small window allows
suturing of the rectal mucosa 2 to 3 cm above the dentate line. e
reduction of blood ow is thought to lead to shrinkage of the hemorrhoidal complex. In addition, a hemorrhoidopexy can be performed
that lis up the prolapsing tissue into its normal anatomic position.
Giordano and colleagues published an extensive review of the current
evidence on THD, looking specically at safety and eectiveness of
the technique. e technique appears safe and ecacious in trained
hands, but it relies primarily upon suture plication of the hemorrhoidal complexes associated with reduction of the prolapse rather
than excision of tissue. erefore, it may be less painful than other
techniques but requires additional operative cost for the disposable
equipment.
POSTOPERATIVE MANAGEMENT AFTER HEMORRHOID SURGERY
Postoperative management is primarily focused on eective analgesia and avoidance of urinary retention and constipation. Options
include a combination of oral and parenteral narcotics, nonsteroidal agents, and local anesthetic blocks. Ketorolac has demonstrated
considerable ecacy in managing posthemorrhoidectomy pain.
e use of alternative administration routes for narcotics either
by patch or subcutaneous pump has been successful in controlling
ANAL AND PERIANAL REGION 15
pain; however, the management of these routes of administration can be risky in the outpatient setting because of the risk of
narcotic-induced respiratory depression, and therefore it is not
recommended.
Urinary retention is a frequent postoperative problem aer hemorrhoidectomy, ranging in incidence from 1% to 52%. A variety of
strategies have been used to treat the problem; the optimal approach
is prevention by limiting perioperative uid administration to 250
mL and avoiding both spinal anesthesia and anal packing.
Early postoperative bleeding (within <24 hours) occurs in approximately 1% of cases and represents a technical issue requiring a return
to the operating theater for resuturing of the wound. Delayed hemorrhage occurs in 0.5% to 4% of cases at 5 to 10 days aer surgery. e
cause is thought to be early separation of the ligated pedicle before
adequate thrombosis in the feeding artery can occur. e bleeding
in this scenario is usually signicant and requires some method for
control of ongoing hemorrhage. Options include a return to the operating theater for suture ligation or tamponade at the bedside with a
Foley catheter or anal packing.
CONCLUSION
e management of symptomatic hemorrhoidal disease should be
adapted to the clinical presentation of the patient and the severity of
the symptoms. e vast majority of patients can be managed in an
oce setting, oen without any procedure at all. When some form
of active treatment is needed, the most appropriate option is selected
based on the anatomy of the hemorrhoids in question and the symptoms reported by the patient.
S u g g e S t e d R e a d i n g
Andrews E. Disastrous results following Whitehead’s operation and the so-
called American operation. Columbus Med J. 1895;15:97–106.
Armstrong DN, Frankum C, Schertzer ME, et al. Harmonic scalpel
hemorrhoidectomy: ve hundred consecutive cases. Dis Colon Rectum.
2002;45:354–359.
Bayer I, Myslovaty B, Picovsky BM. Rubber band ligation of hemorrhoids:
convenient and economic treatment. J Clin Gastroenterol. 1996;23:50–52.
Dennison AR, Whiston RJ, Rooney S, etal. A randomized comparison of
infrared photocoagulation with bipolar diathermy for the outpatient treatment of hemorrhoids. Dis Colon Rectum. 1990;33:32–34.
Ferguson JA, Heaton JR. Closed hemorrhoidectomy. Dis Colon Rectum.
1959;2:176–179.
Franklin EJ, Seetharam S, Lowney J, Horgan PG. Randomized, clinical trial of
LigaSure versus conventional diathermy in hemorrhoidectomy. Dis Colon
Rectum. 2003;46:1380–1383.
Ganchrow MJ, Mazier WP, Friend WG, Ferguson JA. Hemorrhoidectomy re-
visited: a computer analysis of 2038 cases. Dis Colon Rectum. 1971;14:128–
133.
Ganio E, Altomoare DF, Gabrielli F, et al. Prospective randomized multi-
centre trial comparing stapled with open haemorrhoidectomy. Br J Surg.
2001;88:669–674.
Goligher JC. Haemorrhoids or piles. In: Goligher JC, Duthie HL, Homewood
Nixon H, eds. Surgery of the Anus, Rectum and Colon. 5th ed. London:
Baillière Tindall; 1984:98–149.
Haas PA, Fox TA, Haas GP. e pathogenesis of hemorrhoids. Dis Colon Rec-
tum. 1984;27:442–450.
Mado RD. Biblical management of anorectal disease. Breckenridge, CO:
Presented at the meeting of the Midwest Society of Colon and Rectal Surgeons; March 1991.
Morgado PJ, Suarez JA, Gomez LG, etal. Histoclinical basis for a new clas-
sication of hemorrhoidal disease. Dis Colon Rectum. 1988;31:474–480.
Scarpa FJ, Hillis W, Sabetta JR. Pelvic cellulitis: a life-threatening complica-
tion of hemorrhoidal banding. Surgery. 1988;103:383–385.
Senagore A, Mazier WP, Luchtefeld MA, et al. e treatment of advanced
hemorrhoidal disease: a prospective randomized comparison of cold scalpel versus contact Nd:YAG laser. Dis Colon Rectum. 1993;6:1042–1049.
Senagore AJ, Singer MS, Abcarian H, etal. A prospective, randomized, con-
trolled multicenter trial comparing stapled hemorrhoidopexy and Ferguson hemorrhoidectomy: perioperative and one-year results. Dis Colon
Rectum. 2004;47:1824–1836.
Taj an a A . Hemorrhoidectomy according to Milligan-Morgan: ligature and ex-
cision technique. Int Surg. 1989;74:158–161.
Whitehead W. e surgical treatment of hemorrhoids. BMJ. 1882;1:148–150.
Wrobleski DE, Corman ML, Veidenheimer MC, Coller JA. Long-term evalu-
ation of rubber ring ligation in hemorrhoidal disease. Dis Colon Rectum.
1980;23:478–482.
C A F
Siraj Rajaratnam and Ian Lindsey
INTRODUCTION
An anal ssure is a linear tear in the lining of the anal canal that
usually becomes symptomatic because it exposes the internal anal
sphincter and causes painful spasms in that muscle. An anal ssure
is a common condition that signicantly disturbs the quality of life of
persons who experience it.
Most ssures are benign, primary, and idiopathic—that is, they
are typical anal ssures. Atypical ssures are much less common
and occur as a result of other conditions such as Crohn disease,
immunosuppression (including human immunodeciency virus),
malignancy, syphilis, or tuberculosis, or they are drug induced
(e.g., through the use of nicorandil). An atypical ssure is painless,
not situated in the midline, multiple, or associated with a mass or a
stula-in-ano. Management of atypical ssures involves treating the
underlying condition and is beyond the scope of this chapter.
Typical ssures can be arbitrarily classied into acute and chronic
on the basis of duration of symptoms: chronic ssures have been
present for more than 6 weeks. However, certain features are associated with chronic ssures, and the presence of one or more of these
features is possibly a more accurate indicator of chronicity than the
duration of symptoms alone.
Acute ssures are managed with a high-ber diet, stool soeners, and topical local anesthetic ointment. ey will not be discussed
further. is chapter will focus on the clinical assessment, pathophysiologic features, and management of typical chronic anal ssures
(CAFs).
DIAGNOSIS
e diagnosis of CAF can be suspected based on the patient’s history and conrmed with clinical examination. e patient usually
reports having severe, sharp pain at defecation that persists for several minutes to hours aerward and then slowly subsides, with minimal discomfort experienced at other times of the day. CAF is oen
associated with a small amount of bright red blood on the toilet tissue. e patient oen has a history of constipation and straining to
defecate.
Upon examination, the following features of a CAF are observed:
1. A linear ulcer with a brotic rolled edge; the circular muscle
bers of the internal anal sphincter are visible at the base of the
ulcer, and minimal granulation tissue is present.
2. A sentinel skin tag at the caudal (external) apex of the ssure.
3. A hypertrophied anal papilla at the internal apex.
CAF occurs in the midline and is usually posterior but may be
anterior. Fissures away from the midline are atypical.
e caudal end of the ssure oen can be seen upon gentle separation of the buttocks. Digital examination and proctoscopy will
16
conrm the diagnosis but are unlikely to be tolerated because of
anal spasm and pain. An anal block will allow anoscopy, but with
the combination of a typical history and a “shy” anus, it is reasonable to begin empiric management and perform an examination at
a later date when symptoms have improved. However, if the history is atypical, examination should be undertaken with use of an
anesthetic.
Endoanal ultrasonography and manometry are not necessary
in the initial workup but may be useful prior to considering more
invasive treatment options if first-line conservative treatment
fails.
PATHOPHYSIOLOGY
Shearing forces created by passage of hard stool, childbirth,
instrumentation of the anus, or anal intercourse leads to the development of a split in the anal canal mucosa. If this split exposes
the internal anal sphincter, an acute fissure is present. There are
probably two different mechanisms by which an acute fissure may
progress to CAF.
High-Pressure Chronic Anal Fissure
Although the exact pathophysiology of CAF remains obscure, a
baseline hypertonia of the internal anal sphincter appears to be
the most important factor, particularly in posterior CAF. Patients
with posterior CAF have been shown to have higher mean resting
anal pressures than do control subjects. Whether the hypertonia is
the cause of the CAF or a secondary phenomenon caused by pain
is not clear. Nevertheless, treatment of internal sphincter hypertonia remains the focus of management and therefore must at least
be central to the persistence of CAF. Sphincter hypertonia leads
to reduced perfusion pressure of the anal canal, which is more
pronounced posteriorly as a result of a relative paucity of small
arterioles supplying the posterior anal canal. This phenomenon
has been shown in anatomic studies of normal subjects. Reduction of anal pressure by either medical or surgical means is aimed
at improving mucocutaneous blood flow, resulting in healing of
the fissure.
Low- and Normal-Pressure Chronic Anal Fissure
Manometric studies have shown that up to 50% of patients with CAF
do not have increased anal pressures. ese patients are typically
women with anterior midline CAF, which, in small studies, has been
associated with vaginal delivery, external sphincter injury/dysfunction, rectocele, and rectoanal intussusception.
ANAL AND PERIANAL REGION 17
MANAGEMENT
Until 20 years ago, surgery was the mainstay of treatment of CAF.
Manual dilatation of the anus and internal anal sphincterotomy
were the principal surgery therapies; however, increasing focus on
permanent incontinence caused by surgery and the development
of safer conservative treatments have led to a signicant change in
CAF management.
Manual dilatation has been used for almost 200 years. A reduction in anal pressure is achieved by tearing the bers of the internal
sphincter by stretching aer induction of general anesthesia. is
stretching is traditionally performed with the surgeon’s ngers and
is a relatively uncontrolled way of relieving sphincter spasm. Indeed,
the disruption of the sphincter mechanism (especially that caused
by an eight-nger dilatation) carries an unacceptable risk of permanent incontinence. In a 2011 Cochrane review that included seven
studies of manual dilatation versus sphincterotomy, it was found that
the risk of atus incontinence or fecal seepage was as high as 27%
in the dilatation group, with an odds ratio of 4.03 (95% condence
interval [CI], 2.04 to 7.46) when compared with sphincterotomy. In
addition, dilatation is less eective for ssure healing compared with
sphincterotomy, with an odds ratio of 1.55 (95% CI, 0.85 to 2.86) for
persistence of the ssure, leading to the recommendation that use of
manual dilatation to treat CAF in adults be abandoned.
Although internal sphincterotomy still has a role in the management of CAF, it also carries a signicant risk of permanent incontinence and therefore is not the rst-line option.
Topical Creams
Topical creams containing glyceryl trinitrate (GTN) or calcium channel blockers in combination with a stool soener are now established
as the rst-line treatment for CAF. erapy may be initiated by the
primary care physician without the need for specialist assessment or
an anesthetic and with no risk of permanent incontinence.
e most commonly used topical cream is GTN, which causes
vasodilation and relaxation of the internal sphincter muscle via
stimulation of guanylate cyclase and lowering of cytosolic calcium.
A 0.2% cream is applied directly to the anoderm three times daily
for 8 weeks. Symptoms may improve signicantly aer just 1 or 2
weeks, but the full course should be completed to achieve mucocutaneous healing. Although there is no risk of permanent incontinence,
patients can be troubled by adverse eects such as headache (in up
to 50% of cases) as a result of absorption of GTN into the systemic
circulation. is adverse eect may lead to noncompliance because
the headache can be severe and unresponsive to simple analgesics.
e ecacy of GTN cream was assessed in a 2012 Cochrane
review. Healing rates of 48.9% for GTN versus 35.5% for placebo
were found in a meta-analysis of 18 randomized controlled trials that
included a total of 1315 patients. Although this result is statistically
signicant, it demonstrates that more than half of patients will have
persistent CAF aer treatment with GTN. e reasons for this lack of
response to GTN are unclear but probably multiple. Noncompliance,
whether as a result of headache or for other reasons, and tachyphylaxis are possible explanations. Another likely cause of recurrence is
persistent hypertonia of the internal sphincter that makes the patient
“ssure prone.” ese patients may respond to treatment initially,
only to quickly relapse once the resting anal pressure returns to normal at the conclusion of the treatment. Other patients may never
exhibit a reduction in resting pressure despite treatment with GTN. It
also has been demonstrated that patients with long-established CAF
are less likely to respond to GTN. In a case series of 64 patients, the
presence of a sentinel tag (P <.035) and symptom duration of greater
than 6 months (P <.05) were found to be independent predictors of
treatment failure. Various doses of GTN cream have been tested,
ranging from 0.05% to 0.4%, but the dose has not been found to alter
healing rates.
Calcium channel blockers also cause smooth muscle relaxation,
thus lowering resting anal pressure. As with GTN, there is also a
vasodilator eect, further contributing to improved mucocutaneous
blood ow. Diltiazem and nifedipine have been studied using both
oral and topical preparations. A 2% diltiazem cream is the most
commonly used preparation and is applied topically in the same
manner as GTN—three times daily for 8 weeks. A meta-analysis of
seven randomized trials (including 481 patients) comparing topical diltiazem and topical GTN found an equal chance of healing
(relative risk [RR] = 1.10, P < .36), although diltiazem was superior
with regard to overall adverse eects (RR = 0.48, P <.01), headache
(RR = 0.39, P <.0004), and recurrence of CAF (RR = 0.68, P <.006).
Heterogeneity among the trials was signicant. Nevertheless, this
evidence supports the use of diltiazem before the use of GTN.
Botulinum Toxin
Botulinum toxin A (BTX) is a neurotoxin produced by Clostridium
botulinum. It acts on striated muscle by blocking acetylcholine release
at the neuromuscular junction—hence its established role in the treatment of hypertonic skeletal muscle disorders and cosmetic medicine.
Its action on smooth muscle such as the internal anal sphincter is less
clear. In a study of animal subjects it was found that BTX causes a
reduction in noradrenaline release from sympathetic nerves within
the internal sphincter and possibly blocks acetylcholine release in the
sympathetic relay ganglion in the vicinity of the muscle, thus reducing
myogenic tone.
BTX injection is a minimally invasive option for the treatment
of CAF with the aim of reducing resting anal pressure suciently to
allow healing but only for a temporary period (2 to 4 months); consequently, any eect on continence is short-lived.
We inject BTX in the outpatient clinic aer performing a local
anesthetic anal block (10 mL of 0.5% bupivacaine and 10 mL of 1%
lignocaine). When the procedure is combined with a ssurectomy
(described in the next section), it is performed aer induction of general anesthesia. A total of 20 to 40 units of Botox (Allergan, Parsippany, N.J.) or 100 to 200 units of Dysport (Galderma Laboratories,
Lausanne, Switzerland) is mixed with saline solution and injected
with a ne-bore (27-gauge) needle. We inject a divided dose directly
into the internal sphincter on either side of the midline either anteriorly or posteriorly (depending on the location of the ssure). A number of alternative methods have been described, including unilateral
injection, more than two injection sites, and injection into the external anal sphincter, without evidence to suggest that any one method
is best. Given what we know about the mechanism of action of BTX,
it seems logical to inject it either into the internal anal sphincter or
intersphincteric space.
BTX injection is generally well tolerated, and adverse eects
such as temporary incontinence, urgency, and perianal hematoma
are infrequent. e major advantage of BTX is that it does not have
the compliance issues associated with topical creams because a
one-o injection is all that is required. Unfortunately, this does not
translate into improved healing rates. In a Cochrane meta-analysis
of six studies (including 334 patients), BTX was found to be equivalent to GTN, and therefore use of BTX as rst-line therapy cannot
be justied given its increased cost. However, evidence shows that
BTX can be eective in patients who have not responded to initial
management with GTN.
Fissurectomy
e presence of chronic brosis may be an important factor in patients
who do not respond to medical therapy. Fissurectomy—that is, excision of the CAF complex (the hypertrophied anal papilla, sentinel tag,
and brotic scar tissue), thus exposing the healthy underlying internal sphincter with freshened wound edges—treats the chronic brosis
ChroniC AnAl Fissure18
while sparing the sphincter. Fissurectomy alone was shown to result in
excellent healing rates in a case series of 118 patients, but we believe
it is most eective when used in conjunction with medical treatment
of sphincter hypertonia. irty patients who had not responded to
medical management (19 who were treated with GTN and 11 who
were treated with GTN followed by BTX) underwent a ssurectomy
in combination with a BTX injection. e healing rate was 93% at a
median of 16.4 weeks follow-up, and even the patients who did not
heal (n = 2) had signicant symptomatic improvement. ere were no
cases of fecal incontinence and just two patients (7%) reported atus
incontinence, which, in both cases, resolved within 6 weeks.
Cutaneous Advancement Flap
Aer a ssurectomy has been performed, advancing a healthy
ap of perianal skin into the defect appears to be a safe and eective treatment. It is certainly appropriate in persons with low- or
normal-pressure ssures (who are less likely to have responded to
medical treatment), but it is also a good option in persons with
high-pressure CAF who may be at particular risk of incontinence
upon undergoing a sphincterotomy, such as women, older persons,
persons with pre-existing continence disturbance, and persons
found to have a sphincter defect on ultrasound.
V-shaped incisions or rhomboid incisions are made with the furthest extent of the incision approximately 4 cm from the anal verge.
e skin must be mobilized suciently to allow advancement of the
ap into the anal canal without tension, while maintaining the vascular pedicle to the ap through the subcutaneous fat underneath. e
ap is secured over the ssure using interrupted, rapidly absorbable,
braided sutures.
In a series of 54 patients, a V-Y advancement ap led to immediate
healing in 94% of subjects, and the healing rate was 85% with placement of a rhomboid advancement ap in a randomized trial of 40
patients in which this procedure was compared with sphincterotomy
(100%, P = not signicant). e median operating time in the group
that received the ap was 10 minutes.
Lateral Internal Sphincterotomy
Lateral internal sphincterotomy (LIS) remains the single most eective treatment for CAF in terms of ssure healing (>90%). Sphincterotomy has been practiced for 200 years but was popularized by
Eisenhammer in the 1950s. Eisenhammer divided the internal
sphincter in the posterior midline at the base of the ssure, which
resulted in signicant postoperative pain, prolonged healing, and
a “keyhole” deformity that was associated with poor continence.
e technique of sphincterotomy was later rened by Notaras, who
described lateral division of the internal sphincter, which results in
fewer complications.
Surgical Technique
LIS can be performed in the lithotomy or prone jackknife position after induction of general, regional, or local anesthesia.
Bowel preparation and antibiotic prophylaxis are not necessary.
After preparing and draping the perianal region, a Pratt bivalve
speculum or similar anal retractor is inserted into the anus and
the intersphincteric groove is palpated. A short circumferential
incision is made laterally at either 3 or 9 o’clock, and the internal
sphincter is identified. Submucosal and intersphincteric planes
are developed to isolate the internal sphincter, which may then
be divided under direct vision. The caudal part of the internal
sphincter is divided for a variable distance cranially, usually to the
dentate line. The wound may be closed with fine absorbable interrupted sutures or may be left open. Routine postoperative care
typically includes a stool-bulking agent and nonopiate analgesia.
A closed or subcutaneous sphincterotomy is a slight modication of the open procedure and leaves a tiny perianal wound. With
a Pratt’s retractor or nger in the anal canal, a scalpel is inserted in a
lateral position at the intersphincteric groove and advanced cephalad
in either the submucosal or intersphincteric planes. e blade is then
turned laterally (if submucosal) or medially (if intersphincteric) to
divide the internal sphincter while feeling the characteristic “give” as
the tension in the muscle is released. e blade is removed, hemostasis is achieved with pressure, and the wound is le open.
Risk of Incontinence
Although LIS certainly works in achieving CAF healing, incontinence rates of up to 30% have been reported. In a meta-analysis of
22 studies (including 4512 patients) that entailed use of open and
closed LIS techniques and with a minimum follow-up of 2 years, an
overall continence disturbance rate of 14% was reported. e following rates were reported: atus incontinence, 9%; soilage/seepage, 6%;
accidental defecation, 0.91%; incontinence to liquid stool, 0.67%;
and incontinence to solid stool, 0.83%. Concerns regarding permanent incontinence aer LIS are real and signicant. Furthermore,
evidence shows that delayed-onset incontinence may occur, analogous to the development of fecal incontinence many years aer an
obstetric injury.
Tailored Sphincterotomy
A tailored sphincterotomy refers to various technical modications
aimed at reducing the risk of incontinence with LIS by dividing the
minimum amount of internal sphincter required to achieve CAF
healing. In 1997, Littlejohn and Newstead published a report on a
series of 287 patients who underwent LIS that was tailored to stop
at the internal apex of the ssure rather than going up to the dentate
line as traditionally described. is method of tailored LIS is the
most commonly reported and is what we recommend if LIS is to
be undertaken. Littlejohn and Newstead reported excellent results:
the rates of healing, atus incontinence, minor soiling, and urgency
were 99.65%, 1.4%, 0.35%, and 0.7%, respectively. ese results have
been supported by a subsequent randomized controlled trial using
the same tailored LIS technique. Incontinence rates were 2.17% versus 10.86% in the traditional LIS group (P = .039). Healing rates in
the tailored LIS group were slightly lower (but not signicantly so)
and were still excellent (95.65%).
Treatment of Low/Normal Pressure
Chronic Anal Fissure
Nineteen percent of men and 42% of women with CAF have low
or normal resting anal pressures. Performing LIS in this group of
patients would seem illogical, yet it is unclear how LIS can achieve
overall healing rates of greater than 90% because most reports of LIS
do not exclude this subgroup. Nevertheless, we do not recommend
LIS for low- or normal-pressure CAF because these patients must be
at a signicant risk of incontinence with a surgical reduction in rest
ing pressure of 25% (which is normally achieved with LIS).
Low- and normal-pressure CAFs appear to have dierent pathophysiologic features compared with high-pressure CAFs (as previously discussed). ese patients are less likely to respond to topical
smooth muscle relaxants and may even show an atypical contractile
response of the internal sphincter to BTX. Fissurectomy with or without cutaneous advancement ap is the surgical treatment of choice
for these patients. If this treatment fails, underlying anorectal dysfunction, such as rectocele and rectoanal intussusception, should be
considered, and appropriate investigation and management should
be undertaken. Successful treatment of CAF in highly selected
patients has been reported with levatorplasty, stapled transanal rectal
resection, and sacral neuromodulation.
-
ANAL AND PERIANAL REGION 19
Female with anterior fissure
Preexisting incontinence
Older age group
Significant chronic fibrosis
Topical GTN 0.2% cream (or Diltiazem 2% if intolerant to GTN)
No significant fibrosis
BTX injection
under local anaesthesia
Advancement flap
Anal manometry
and ultrasound
High fiber diet, Stool-softener
Fissurectomy and BTX injection
under general anaesthesia
Male with
High resting
pressure
SUMMARY: CHOICE OF TREATMENT
CAF is a common condition with several treatment options.
Although a large volume of literature exists regarding CAF, making
sense of it in clinical practice is somewhat dicult because of dierences in technique and use. Many studies directly compare just two
therapeutic options and are limited by a small sample size and a short
follow-up period. In addition, the vast majority of investigators do
not distinguish between high-pressure and low- or normal-pressure
CAF, which appear to have dierent pathophysiologic features. Studies of treatment algorithms would be more useful for a condition such
as CAF. Management algorithms for CAF may reduce the need for
LIS (as well as the associated risk of permanent incontinence) and
reduce costs by targeting use of endoanal ultrasound and manometry. Our algorithm is presented in Figure 3-1.
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