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14 Anal Fissure andAnal Stenosis
245
a
b
c
Fig. 14.2 Open sphincterotomy. (a) A radial incision exposes the muscle (b). The distal most internal sphincter muscle
is dissected. (c) The muscle is divided with cautery
most distal bers of the internal muscle before
performing the sphincterotomy.
Closed PLIS: The “reverse Notaras” is similar
to the open approach but omits the skin incision
and the tissue dissection (Fig. 14.3). An appropriately sized Hill-Ferguson or Sawyer retractor
accentuates the bow-stringing of the internal anal
sphincter muscle. The muscle is palpated and the
caudal extent of the muscle is appreciated at the
inter-sphincteric groove. A narrow, angled scalpel (like #11) is passed through a stab incision in
the lateral position in the inter-sphincteric groove
ush with the internal sphincter muscle. With
the surgeon’s index nger in the anal canal as a
guide, the blade is turned perpendicularly inward
toward the anal canal. Fine motion of the pointed
tip of the scalpel during its removal produces
blind, sharp division of the distal aspect of the
internal anal sphincter muscle with, as described
by Notaras, a “characteristic gritty sensation that
is felt through the scalpel handle”. Care should
be taken to avoid cutting through the mucosa as
this can result in abscess or stula. Dividing the
Fig. 14.3 Closed sphincterotomy. The distal most internal sphincter muscle is divided taking care not to incise
the mucosa
internal sphincter muscle causes an immediate
release in tension across the retractor. As with the
open technique, pressure is held for hemostasis and to fracture any remaining muscle bers.
246
D. L. Feingold and S. A. Lee-Kong
The closed technique, originally described with
placing the blade under the anoderm and dividing
the muscle by turning the blade outward toward
the inter-sphincteric groove, was modied for
simplication and reproducibility and to reduce
unwanted injury to the external sphincter muscle. Unintentional damage to the external anal
sphincter during PLIS has been implicated in the
development of post-PLIS dysfunction.
Laterality of PLIS is usually chosen based
on the presence or absence of lateral internal
hemorrhoid cushions. Patient positioning, type
of anesthesia and closing the wound after PLIS
are decided according to the preference of the
surgeon and, likely, do not inuence outcomes.
Associated skin tags and papillas are typically
excised or fulgurated concurrently with PLIS and
debriding the ssure (ssurectomy) may facilitate healing. It is rare to have symptomatic hemorrhoids requiring operative treatment at the time
of PLIS and, depending on the circumstances,
addressing the chronic ssure and leaving the
hemorrhoids alone is usually the better course
of action. Post-PLIS, patients are given standard
post-anal surgery instructions regarding stool
softeners, hot baths, multi-modality analgesia
and “red ag” symptoms to watch out for.
Since the original descriptions of PLIS for the
treatment of ssure, the technique has been studied in terms of the ideal location of the sphincterotomy around the circumference of the anal canal
as well as the preferred approach (open versus
closed). Early descriptions of PLIS involved posterior midline sphincterotomy which was associated
with prolonged healing times and risked causing a
deep groove-like defect that interfered with complete closure of the anal canal at rest and resulted
in leakage (“keyhole” deformity). Sphincterotomy
in the lateral position effectively avoids this anal
canal furrow and supplanted posterior sphincterotomy as the standard location for PLIS.
In terms of the operative approach to PLIS,
a large retrospective study relying on mailed
patient questionnaires obtained clinical follow-up information an average of 3years after
PLIS [6]. The authors compared 324 open PLIS
patients with 225 closed PLIS patients and demonstrated comparable success in terms of heal-
ing and recurrence and that the closed technique
was associated with statistically signicantly less
anal dysfunction (41% versus 33%). A randomized, controlled study comparing 40 patients
who underwent open PLIS with 36 patients who
underwent closed PLIS with 1year of follow-up
demonstrated no statistically signicant differences in post-operative pain or incontinence [7].
A Cochrane review also demonstrated that properly performed lateral sphincterotomy using the
open or closed approach yielded equivalent outcomes [8]. The PLIS approach should be chosen
based on surgeons’ preference and familiarity
with the procedure.
The evolving recognition and appreciation
of unwanted functional consequences related to
sphincter muscle division have inuenced which
patients are recommended to undergo PLIS and
how the operation is technically performed. As
the risk of incontinence and the risk of ssure persistence are related to the degree of muscle division, the extent of sphincterotomy during PLIS
remains controversial. Traditionally, in order to
effectively relax the hypertonic internal sphincter
muscle, PLIS was recommended up to the level
of the dentate line. More recently, a renement
in the technique has been recommended limiting
the extent of sphincterotomy to the apex of the
actual ssure. “Tailored” PLIS was studied in a
randomized, controlled trial including 46 patients
who underwent traditional PLIS and 46 patients
who underwent PLIS to the level of the apex of
their ssure [9]. These authors demonstrated that
female patients who had a least one prior vaginal
delivery who underwent a more extensive PLIS
had faster pain relief and faster ssure healing but
were more likely to have some degree of postoperative incontinence as compared with patients
who had a more limited PLIS. Other similarly
constructed randomized, controlled trials have
also demonstrated quicker healing but higher anal
dysfunction rates associated with more extensive
sphincterotomy and higher recurrence rates and
less incontinence after more limited PLIS [10].
“Calibrated” PLIS has been suggested, a well, in
an effort to standardize the extent of muscle division. This method utilizes a conical, calibrated
scale to control the degree of PLIS.
14 Anal Fissure andAnal Stenosis
247
An alternative to traditional, tailored or calibrated PLIS was suggested in a prospective study
of 31 women with chronic anal ssure who failed
medical therapy and underwent subsequent PLIS
up to the level of the apex of their ssure [11].
After healing, patients underwent three-dimensional anal ultrasonography demonstrating that
women who had less than 25% of their internal
anal sphincter muscle divided at the time of PLIS
were less likely to experience post-operative
functional complications. This length of sphincterotomy amounted to less than 1cm. Surgeons
must weigh the risks of cutting too much muscle
and jeopardizing continence with not cutting
enough muscle and leading to ssure persistence
due to inadequate relief of sphincter hypertonicity. Adopting a prudent “less is more” approach to
PLIS and appreciating that women typically have
less bulky sphincter muscle and shorter length of
muscle as compared with men is important.
Another potential contributing factor inuencing the rate of post-operative incontinence
includes pre-existing occult sphincter injury
from prior anal surgery or obstetric trauma.
It is important to consider that patients with
asymptomatic anal sphincter injury, commonly
due to vaginal delivery, may manifest with anal
dysfunction after additional sphincter disruption from subsequent PLIS. A retrospective
study relying on mailed patient questionnaires
obtained clinical follow-up information an average of 4years after PLIS and demonstrated that
women who had more than one vaginal delivery
were more likely to experience long-term gas
incontinence [12].
Alternative Treatment Concepts
Given the potential functional consequences of
PLIS, a number of alternative treatments have
been proposed. Patients with prior sphincter
damage, baseline incontinence, chronic diarrhea,
hypotonic muscle or desire to reduce the risk of
incontinence may consider muscle-sparing treatment options. Combining ssurectomy with
botulinum toxin injection was reviewed earlier.
Other novel applications, like sacral nerve stimulation, will not be reviewed in detail.
Subcutaneous Fissurotomy
The presence of a short sinus or stula emanating from a ssure bed is a poorly described entity
related to chronic anal ssure (“ssure-stula”).
The tract, when present, is typically a short, subcutaneous sinus extending from the distal apex
of the ssure towards or under the sentinel skin
tag. This is generally considered a manifestation
of the chronicity and severity of inammation
related to the ssure, rather than the result of an
infection, and is treated by simply laying open the
tract at the time of PLIS.The tract is not always
readily apparent, and the surgeon should carefully evaluate the ssure for the presence of such
a tract. In rare situations where a stula is present
involving muscle, the operative plan or degree of
sphincterotomy may need to be adjusted.
A potential muscle-sparing alternative to PLIS
involves treating the chronic anal ssure for what
it is, a chronic, non-healing wound, and incorporates minimal dilation (enough to accommodate
a conventional anoscope) with debridement and
cauterization of the ssure and subcutaneous
ssurotomy with laying open of the sinus tract.
Unroong the sinus widens the distal anal canal,
theoretically, obviating the need for PLIS and ssurectomy effectively freshens a chronic ssure
creating an acute ssure that may go on to heal
without muscle division [13]. This approach has
been combined with triamcinolone injection into
the base of the ssure with encouraging results.
It is important that patients follow standard postanal surgery instructions to facilitate ssure
healing and avoid re-opening or aggravating a
healing ssure. The concept of treating ssures
as chronic, non-healing wounds is supported by
the anecdotal success of hyperbaric oxygen therapy in healing recalcitrant ssures.
Dilation
Performing uncontrolled, aggressive (four ngers or
more) manual anal dilation to relieve the hypertonia
of anal ssure (similar to the procedure described
by Lord for the treatment of hemorrhoids) traumatizes the sphincter complex, unreasonably jeopardizes function, and has been relegated to historical
mention. Meanwhile, controlled, standardized anal
dilation using a 40mm diameter pneumatic balloon
248
ab
D. L. Feingold and S. A. Lee-Kong
in the setting of chronic anal ssure has been studied in randomized, controlled fashion and may be
a viable alternative to PLIS [14]. The 24 patients
who underwent controlled dilation, as compared
the anal canal, the ssure base is prepared with
curettage and the brotic edges are excised (ssurectomy). A more detailed review of aps follows in the section on anal stenosis.
with 25 patients who underwent PLIS, had reasonable healing rates (83% versus 92%) and less
incontinence after 24months of follow up (0% versus 16%). Further study regarding efcacy, safety
and recurrence rates will determine the utility of this
technique.
Simple Cutaneous Advancement Flap
A trapezoid, broad-based skin ap with a length
at least 1.5 times the length of the ssure and a
base at least twice the width of the apex of the
ap preserves the blood supply of the ap and
affords tension-free reach to cover the ssure.
Flaps
Introducing healthy, well-perfused tissue to the
ischemic wound of a chronic ssure has a high
chance of success and carries minimal risk of
anal dysfunction. Before aps are advanced into
These full-thickness aps consist of skin and
subcutaneous fat dissected up off the subcutaneous external sphincter muscle. Once advanced,
the ap is secured to the mucosa along its apex
and to the anoderm along its sides (Fig.14.4).
Fig. 14.4 Simple
cutaneous advancement
ap. (a) The ssure bed
is prepared and the sides
of the ap are incised.
(b) The full thickness
dermal ap is raised.
(c) The ap is sutured in
place
c
14 Anal Fissure andAnal Stenosis
249
V-Y Advancement Flap
These aps, oriented pointing toward the buttock, are mobilized with minimal undermining to
preserve vascularity. Flaps are advanced into the
anal canal without tension and are sutured to the
dentate line. Closing the donor site wound helps
advance the “V” into the anal canal. Primary
closure of the wound facilitates healing and
recovery. V-Y advancement aps are simple to
construct and can also be fashioned obliquely to
avoid using midline skin (Fig.14.5).
a
Unique Situations
Post-PLIS Fissure
Persistence or recurrence of ssure after PLIS is
usually due to inadequate sphincterotomy that
fails to adequately relieve the hypertonia of the
internal sphincter muscle. Alternatively, this
circumstance raises the possibility of an atypical ssure and a careful assessment, possibly
with ssure biopsy, should be performed. Before
proceeding with repeat PLIS, patients are often
managed initially non-operatively to try to effect
healing and frequently undergo anorectal physiology testing to objectively assess the sphincter
complex. Repeat PLIS is usually done at the contralateral position across from the original PLIS
and, in selected patients, is associated with excellent healing rates and low incontinence rates.
Muscle-sparing alternatives, like aps, are often
considered in this situation in order to reduce the
risk of anal dysfunction. Patients with ssures
who have had a prior stulotomy or other anal
sphincter injury are typically managed according
to the same algorithm as patients with post-PLIS
ssure.
b
Fig. 14.5 V-Y advancement ap. (a) The ssure bed is
prepared and the “V” ap is marked. (b) The lateral aspect
of the donor wound is closed rst to advance the ap into
the anal canal and then the ap is secured in place
Hypotonic Fissure
Absence of hypertonicity (normal or hypotonic
“low pressure” sphincter) is more commonly seen
in patients who are elderly, post-partum, female
or who have anterior-based ssures. Patients with
chronic ssure without the typical hypertonic
internal anal sphincter should be considered for
muscle-sparing therapy as sphincterotomy in this
situation risks non-healing and anal dysfunction.
Anal manometry may be helpful to objectively
determine resting tone and can be useful when
counseling patients.
Extreme Pain
A subset of patients present with severe pain
greatly affecting their life. Often these patients
cannot sit, miss work due to their disabling ssure and have become professionally and personally dysfunctional. Patients with this degree
of symptoms commonly use a combination of
topical anesthetics, narcotics and oral laxatives
that produce liquid movements to blunt the s-
250
D. L. Feingold and S. A. Lee-Kong
sure pain. Fissure patients with this extreme presentation may actually be stulizing through the
base of their ssure. While counselling highly
symptomatic ssure patients about non-operative
treatment is standard, many of these patients will
opt for expedited examination under anesthesia
to conrm their diagnosis and effect therapy. In
patients with extreme pain without evidence of
a ssure or overt signs of infection on external
exam, fever, difculty voiding or rapidly worsening pain over a few days raises the suspicion of an
occult inter-sphincteric abscess, or other soft tissue infection, and these patients should be diagnosed and treated by prompt examination under
anesthesia.
Inammatory Bowel Disease
Fissures occur more frequently in patients with
IBD than in the general population and IBD
related ssures are commonly atypical appearing
(deep, broad), off-midline or multiple (Fig.14.6).
Compared with patients with ulcerative colitis, the rate of ssuring is higher in patients
with Crohn’s disease and for unclear reasons, a
subset of Crohn’s disease patients have asymptomatic ssures. Classically, ssures in patients
with Crohn’s disease are accompanied by large,
edematous skin tags (“elephant ears”), which
often are the reason for presentation. Patients
with pain commonly have a degree of anal stenosis as well and are frequently taken for examination under anesthesia to exclude a suppurative
process or stula and to dene the anatomy.
Fissures in Crohn’s disease patients pose
unique diagnostic and therapeutic challenges
and a multi-disciplinary approach is helpful to
evaluate the presence and extent of proximal
Crohn’s disease and to coordinate medical and
surgical therapy. As these patients often have
chronic diarrhea, are at risk for requiring future
anal surgery to address stulizing disease, and
are purported to have poor wound healing ability, they are routinely rst treated non-operatively. While standard medical therapy options
used to treat patients with idiopathic ssures are
also applicable to IBD patients, patients who
fester on medical therapy are at risk for developing abscess or stula at the site of their ssure
[15]. Small case series describe that in carefully
selected, symptomatic, non-healing Crohn’s disease patients without active proctitis, PLIS is
safe and efcacious [16].
HIV-Related Fissure
Patients with HIV may present with typical, idiopathic ssures that may be treated in similar fashion as ssures found in sero-negative patients.
Alternatively, some patients develop atypical anal
ulcerations similar to ssures related to Crohn’s
disease that can appear deep, broad-based or cavitating (Fig.14.7). These lesions may be due to a
variety of infections and are often associated with
lax sphincter tone. The evaluation and treatment
of these patients must be individualized and coordination with patients’ infectious disease doctors
is often helpful.
Fig. 14.6 Intra-operative photo of a patient with Crohn’s
disease demonstrating a broad, deep ssure. Courtesy of
Dr. Daniel L.Feingold
Non-healing Wounds
Patients with persistent wounds from excisional
hemorrhoidectomy or other anal operation, from
trauma or ano-receptive practices or in the setting of prior radiotherapy require careful consideration before proceeding with operation.
Appreciating that these patients do not have typical, idiopathic ssures is important and consid-
14 Anal Fissure andAnal Stenosis
Fig. 14.7 Intra-operative photo of a patient with HIV
demonstrating an inltrative, deep, off-midline ssure.
Courtesy of Dr. Scott R.Steele
ering underlying etiologies with tissue biopsy or
culture may be required. Often, in this situation,
the anal canal lacks hypertonicity and musclesparing treatment options should be considered.
Anal Stenosis
Introduction
Anal stenosis is a rare, potentially incapacitating
narrowing of the anal canal due to loss of epithelium and scarring. Treatment options, modulated
depending on the severity of stenosis, range from
medical therapy with stool softeners and bulking agents to dilation to anoplasty. The surgical
management of anal stenosis can be particularly
technically challenging.
Pathogenesis
The majority of cases of anal stenosis are
caused by excessive or abnormal scarring after
multi-quadrant hemorrhoidectomy. To reduce
the occurrence of this complication, it is important, when performing hemorrhoidectomy, to
251
leave muco-cutaneous bridges of healthy tissue
in between the columns being excised. Radical
anal surgery can replace the normally pliable
anoderm and mucosa with brotic, unforgiving,
non-compliant scar that can gradually progress
to stenosis that may not dilate adequately during defecation. Stenosis may result from other
anorectal operations such as Delorme, transanal tumor excision, excision and fulguration
procedures or anal anastomoses. Anal stenosis
can also occur after stapled hemorrhoid surgery,
though this is technically rectal stenosis due to
the nature of the mucosectomy performed. Other
causes of acquired anal stenosis include chronic
diarrhea, long-term mineral oil or other laxative
abuse (“parafn anus”), trauma, IBD, radiotherapy, tuberculosis, perineal sepsis, and a variety
of infections.
Presentation
Anal stenosis causes difcult or painful evacuation and patients often present with bleeding and
narrow caliber stools. Patients with more severe
stenosis can have truly debilitating symptoms.
Similar to patients with highly symptomatic ssures, some stenotic patients experience “food
fear” whereby they limit oral intake to decrease
the frequency of difcult, painful bowel movements. The majority of patients report antecedent
hemorrhoidectomy. Symptoms or bouts of fecal
impaction lead many patients to rely on combinations of diet modication, oral laxatives and
enemas to ameliorate symptoms. Patients may
report leakage, tenesmus, frequency, incomplete
evacuation or other anal dysfunction. Physical
examination with visual inspection and careful digital exam usually conrms the diagnosis.
Patients with more severe stenosis will not tolerate ofce digital exam and require examination under anesthesia. Differential diagnosis
for patients presenting with anal stenosis might
include malignancy, ssure, constipation or hemorrhoid disease.
Stenotic patients are classied subjectively
according to the severity of anal stenosis. Mild
stenosis describes a tight anal canal that can be
252
D. L. Feingold and S. A. Lee-Kong
relatively easily examined with a well-lubricated
examining nger. A moderate stenosis requires
some degree of forceful dilation to insert an
index nger and severe stenosis requires even
more force to insert the smallest Hill-Ferguson
retractor or fth digit. Stenoses can also be categorized according to their length ranging from
a focal, short, veil or diaphragm to a ring-like,
annular segment typically less than 2cm in length
to a tubular or diffuse stenosis longer than 2cm.
Describing stenoses according to their height in
relation to the dentate line as low (the majority of
stenoses), middle or high is also helpful.
Medical Treatment
While all patients with stenosis can be initially
managed non-operatively, patients with a mild
stenosis are most amenable and most likely to
respond to this treatment. Stool softeners and
ber supplementation with adequate water intake
to bulk up the stools provide gradual and natural
dilation for these patients. An adequately long
course of medical therapy is warranted before
moving to more invasive treatment.
Dilation
Daily self-dilation using a well-lubricated,
smooth mechanical dilator, like a Hegar cervical dilator, can, over time, gradually expand the
anal canal and improve symptoms of stenosis.
Typically, the rst dilation is done under anesthesia, which may be combined with longitudinal,
releasing anotomies or sticturotomies. The benet of these relaxing incisions is questionable and
depends on the degree and length of stenosis and
the quality of the tissues. There is a concern that
relaxing incisions can actually cause scarring and
brosis along the anal canal further exacerbating
the stenosis. Dilation may be particularly helpful for stenosed patients with Crohn’s disease or
prior radiotherapy in whom surgical options are
limited. Although successful in many patients
with mild stenosis, some patients do not tolerate self-dilation. Dilation of more severe stenosis
may cause trauma resulting in counter-productive
brosis and further contracture and deterioration
in function; these patients usually require augmentation anoplasty.
Operative Therapy
Operative intervention is usually reserved for
patients with moderate or severe stenosis who
have failed the medical therapy outlined above.
In cases where a functional stenosis contributes to
narrowing of the anal canal, open PLIS (reviewed
previously) can be helpful in alleviating symptoms, and, after careful consideration, PLIS may
be performed in conjunction with anoplasty,
depending on the anatomy and circumstances.
Stricturoplasty
A short mucosal stricture after stapled hemorrhoid
surgery may be corrected by dividing the stricture
longitudinally and then closing the defect transversely similar to a small bowel stricturoplasty.
For more effective stricturoplasty, this release and
closure can be repeated contra-laterally along the
circumference of the stricture [17].
Flaps
The ideal operation to correct anal stenosis
restores function, prevents recurrent stenosis and
has a low risk of post-operative morbidity. Flaps
bring in healthy, vascularized tissue to augment
the anal canal restoring pliability and capacity and are the procedures of choice when less
invasive interventions fail. The type of anoplasty
used in a particular patient depends on the surgeon’s familiarity and preference and on unique
patient anatomic factors like the height, length
and degree of the stenosis and the skin available
for use (Fig.14.8).
A simple advancement ap maintains its blood
supply across an intact skin bridge (Y-V, mucosal advancement, rotational aps). An island or
pedicle ap lacks a skin bridge and receives its
blood supply from the underlying fatty pedicle
(V-Y, diamond, house aps). Careful attention to
preserving blood ow when mobilizing aps and
limiting undermining help prevent ap necrosis.
Minimizing tension across the ap is important and can be technically challenging. Prior
14 Anal Fissure andAnal Stenosis
253
Fig. 14.8 Comparison
of the conguration of a
variety of anoplasty
aps. (a) Mucosal
advancement ap. (b)
Y-V ap. (c) V-Y ap.
(d) Diamond ap.
(e) House ap. (f)
Rotational “S” aps
a
b
c
d
e
f
to securing a ap in the anal canal, the brotic
bed of the stricture should be divided or excised
and freshened to accept the graft. Failing to
adequately release or prepare the bed or compromising the vascularity of the ap risks failure of
the ap. Flaps are typically performed in prone
position with on-table intravenous antibiotic and
bowel preparation depends on surgeon preference. Complications after ap procedures may
include ap necrosis, sloughing or dehiscence,
persistent stenosis or anal dysfunction, infection,
pruritis, and non-healing donor sites. In extreme
cases of refractory stenosis, patients may require
fecal diversion.
254
D. L. Feingold and S. A. Lee-Kong
Mucosal Advancement Flap
Similar to a rectal advancement ap used to treat
stula-in-ano, this ap survives off the submucosal plexus and is most applicable to mid-level or
higher stenosis. In order to prevent the creation
of an ectropion, when addressing a more distal
stenosis, the external most aspect of the wound
may be left uncovered.
Y-V Advancement Flap
While the narrow apex does not augment the anal
canal as much as a broad ap and the pointed
conguration risks necrosis at the apex, this ap
is simple to construct and is effective for strictures distal to the dentate line. A “Y” shaped
vertical incision starting at the prepared stenosis
bed allows mobilization of the full-thickness “V”
shaped ap. The two oblique limbs of the ap
are typically 5–8cm in length. This ap can be
created extending radially from the anus or can
be congured obliquely, as needed, similar to the
V-Y ap reviewed earlier.
V-Y Advancement Flap
This ap, reviewed earlier in the treatment of ssure, can also be used to treat ectropion or stenosis.
The conguration of this ap advances well into
the anal canal and is useful in severe anal strictures.
a
b
c
House Flap
This is a modication of the V-Y anoplasty and
provides a broad pedicle skin ap that can augment the length of the stenotic anal canal and permits primary closure of the donor site despite the
width of the ap (Fig.14.9). This ap of skin and
subcutaneous fat maintains its blood supply from
underlying perforators and the conguration does
not come to a narrow point making it less prone
to ischemic necrosis. As with V-Y aps, closing
the donor wound helps advance the ap into the
anal canal. The width of the ap should match
the width of the mucosal defect to be covered and
should not exceed about 25% of the circumference of the canal. As with other congurations,
if further augmentation is required, bilateral aps
may be constructed (Fig.14.10).
d
Fig. 14.9 The house ap anoplasty. (a) The strictured
anal canal is incised longitudinally to release the scar. (b)
Perpendicular incisions are made. (c) The anal canal is
prepared to accept the ap. (d) The ap is advanced into
the anal canal behind the closure of the donor site