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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_927_Библиотеки_им_академика_М_И_Перельмана.pdf
RECT
AL AND
PARARECTAL
19. Fecal Incontinence 93
20.
Rectal Stricture: Etiology and Management 98
21.
Management of Fecal Impaction 102
22.
Rectal Prolapse 107
23.
Solitary Rectal Ulcer Syndrome 111
24.
Rectocele 114
25.
Rectal Foreign Bodies 118
26.
Diagnosis and Management of Sacral and Retrorectal
Tumors 121
REGION
Management of Rectal Villous Tumors 132
27.
28.
Preoperative Evaluation of the Patient with Rectal
Cancer: Staging and Strategy 135
29.
Cancer of the Rectum: Neoadjuvant Therapy 141
30.
Cancer of the Rectum: Operative Management 146
31.
Local Treatment of Rectal Cancer 152
32.
Locally Recurrent Rectal Cancer: Management and
Follow-up 157
33.
Perineal Hernia 162
2
91
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F
I
P
. Ronan O’Connell
INTR
ODUCTION AND INCIDENCE
F
ecal incontinence may be dened as the inability to voluntarily control the release of atus or stool until a socially convenient time and
place. Fecal continence, which is learned in childhood, is one of the
most important social milestones in development, and its loss is a
devastating handicap. e prevalence of incontinence varies by gender, age, and denition; however, as many as 2% of women regularly
experience diculty controlling stool and at least 10% have diculty
controlling atus. Incontinence is more common in parous women
because childbirth is the most common cause of pelvic oor injury.
Menopause also contributes through diminished trophic eects
of estrogen on pelvic connective tissues, and symptoms frequently
become manifest in the sixth or seventh decade. e overall cost of
fecal incontinence to society is unknown, but the magnitude of the
problem is illustrated by the fact that fecal incontinence is the second
leading reason for admission of elderly persons to nursing homes—a
reason more common than dementia. e hidden cost is a reduction in quality of life and lost opportunities resulting from this most
embarrassing of symptoms.
C
AUSES
ecal continence depends on the presence of an intact anal sphinc-
F
ter mechanism, coupled with adequate rectal compliance and a normal volume and consistency of stool. A wide variety of anatomic
and physiologic factors can alter continence, particularly changes
in colonic transit and stool consistency, abnormal rectal physiology, abnormal anorectal sensation, pelvic oor denervation, and
disruption of the integrity and function of the internal and external
anal sphincters. In general, the four main causes are (1) abnormal
stool volume and consistency; (2) neurologic disorders leading to
sphincter weakness; (3) anatomic defects in the anal sphincters; and
(4) abnormal rectal physiology. Because these problems oen overlap, each area must be addressed to ensure accurate diagnosis and
eective treatment.
ASSESSMENT
Many scoring systems have been proposed to categorize the severity
of fecal incontinence. e use of such systems is important for accurate patient assessment, medicolegal documentation, and objective
evaluation of treatment outcomes. Each scoring system has strengths
and weaknesses. e ideal system would accurately and reproducibly
describe the frequency of incontinent episodes, the degree to which
patients are incontinent of gas, liquid, and solid stool, and the eect
of incontinence on lifestyle. Two validated scoring systems are widely
used: the Cleveland Clinic Continence Score and the St. Mark’s Continence Score. Quality of life scores should be determined independently.
Use of the validated Fecal Incontinence Quality of Life symptomspecic score is helpful because it is the patient’s quality of life that is
the most important determinant of the need for intervention.
Evaluation of fecal incontinence begins with a detailed interview
that includes a careful medical, surgical, and obstetric history. e
timing and type of incontinence should be noted, as well as the use of
pads, diapers, or medications. It is important to ascertain the severity
of the incontinence, which may vary from soiling to loss of a complete bowel movement, and whether the incontinence is primarily
associated with urgency and the inability to hold the rectal contents
or is passive. Many patients have a combination of symptoms that
may include obstructed defecation with incomplete evacuation.
Obtaining a dietary history is important because many patients
consume inappropriately high amounts of fermentable ber in the
mistaken belief that a “healthy diet” is required for their bowel condition. Oen breakfast is omitted, particularly by working mothers,
and thus the opportunity to use the gastrocolic reex to ensure a predictable early morning bowel movement is lost.
Physical examination should include exible sigmoidoscopy to
rule out neoplastic and inammatory disorders, with further evaluation of the small and large bowel as clinically indicated. e perineum
is inspected for scars, stulas, and adequacy of the perineal body. e
presence of rectal prolapse or perineal descent is appreciated by asking the patient to bear down. Digital examination at rest and with
squeeze eort permits qualitative assessment of internal and external
sphincter function. e presence and extent of a rectocele or uterine
prolapse should be determined.
Endoanal ultrasonography is the best technique currently available to evaluate patients for possible anatomic anal sphincter defects
and should be performed in all patients with incontinence. e relationship between the extent of an individual anal sphincter defect
and continence is dicult to correlate; however, defects extending to
one quadrant (90 degrees) or greater usually contribute signicantly
to a patient’s symptoms. Defects in the external anal sphincter (EAS)
are associated with urge incontinence, whereas internal anal sphincter (IAS) defects are associated with passive soiling and leakage of
mucus. Occult anal stulas and other less common pathologic conditions also may be identied using endoanal ultrasound, and threedimensional imaging may be useful in assessing the extent of injury.
In expert hands, transperineal ultrasonography provides detailed
anatomic images and may allow dynamic assessment of rectocele,
rectal intussusception, and levator ani injury.
Patients considering surgery because of the severity of their
incontinence should undergo anorectal physiologic assessment. Anal
manometry documents resting and squeeze pressures, indicating IAS
and EAS function, respectively. Rectal sensation may be assessed using
balloon distention to determine the volume of rst sensation, volume
of rst urge, and maximum tolerated volume. Pudendal nerve function may be evaluated noninvasively by determining pudendal nerve
terminal motor latency with a glove-mounted electrode; however, the
results are not predictive of therapeutic outcome, and the technique is
93
94
Fec
al Incont
Inence
ot routinely performed. Concentric nerve electromyography of the
n
EAS can accurately determine the presence of motor neuropathy, and
the cliteroanal reex can be used to determine aerent and eerent
conduction along the pudendal nerve and its terminal branches. In
practice, such investigations are rarely performed.
Defecography provides a dynamic view of rectal function and
permits identication of pelvic oor disorders such rectocele or
internal intussusception that can contribute to incontinence through
obstructed defecation and incomplete evacuation.
TREA
TMENT
T
reatment should be individualized based on the severity of symptoms, the patient’s overall condition, and the degree to which the
incontinence is aecting the patient’s quality of life.
Medical Management
rue incontinence must be dierentiated from pseudoincontinence,
T
soiling of mucus or pus caused by prolapsing hemorrhoids, full-thickness
rectal prolapse, or occult stulas. In these instances, therapy is directed
at the primary cause. Conservative management is appropriate for true
mild incontinence and is focused on optimizing stool consistency and
colonic motility. Excess fermentable ber should be excluded from the
diet and replaced by ber supplements taken once or twice daily to provide a so, bulky stool. Patients with loose stools should be instructed
to take only enough water to dissolve the bulking agent, thus permitting
maximal absorption of excess stool water. Judicious use of antidiarrheal
agents such as loperamide or diphenoxylate with atropine is appropriate
to decrease stool frequency. Frequently, these drugs are most helpful at
bedtime or prior to planned social engagements. Loperamide has been
shown to increase internal anal sphincter pressure and may help minor
degrees of seepage from a lax anus. In some patients, the adult dose of
loperamide (2 mg) leads to constipation, and in these circumstances,
1 mg pediatric syrup is useful. Some patients, particularly those with
chronic seepage, also may benet from regular emptying of the rectum
with a small tap-water enema.
eedback
Biof
Biofeedback is a dynamic technique that allows a person to learn and
respond to physiologic changes in the body. In the case of fecal incontinence, patients are trained to improve voluntary anal sphincter
contraction, improve rectal sensation, and coordinate squeeze eorts
with rectal distention. Biofeedback represents a qualitative improvement over simple pelvic oor exercises, such as those popularized
by Kegel, because the patient learns to focus eorts upon the appropriate target, the EAS, rather than the gluteus maximus. Biofeedback
is painless, noninvasive, relatively inexpensive, and risk free. Rectal sensory training is accomplished by instillation of progressively
smaller quantities of air into a rectal balloon.
Requirements for biofeedback therapy include motivation, the ability
to follow instructions, and the ability to contract the sphincter muscle
to a detectable degree. Specic indications for biofeedback include neurogenic fecal incontinence, inability to undergo surgery, and failure of
sphincteroplasty. e eects of biofeedback on incontinence are reasonable, with most patients experiencing sustained improvement.
Surger
Anal Sphincter Repair (Sphincter
Anal sphincter injury is most commonly due to obstetric trauma, with
the site of injury in the anterior quadrant of the anus. In other patients,
y
oplasty)
such as those who have had previous anorectal surgery, perineal injury,
or pelvic fractures, the site and extent of a suspected sphincter injury
may be dicult to determine upon clinical examination, and endorectal ultrasonography may be required to dene sphincter anatomy.
Acute anal sphincter injuries, particularly those that occur during
childbirth, are best repaired at the time of injury. e repair should be
performed under optimal conditions in the operating room, rather
than in the labor ward. If an obstetric injury has been missed or the
primary repair breaks down, secondary repair should be delayed
until local inammation and edema have completely resolved.
Patients undergoing elective anal sphincteroplasty may need to
perform full mechanical bowel preparation; however, an enema on
the morning of the surgical procedure is usually adequate. Perioperative broad-spectrum parenteral antibiotics should be prescribed.
e operation may be performed with the patient in a lithotomy or
prone jackknife position and the buttocks taped apart. Prior to incision, inltration of the operative eld with a 1:100,000 adrenaline
solution is helpful and particularly aids in dissection of the rectovaginal septum. When the perineum is foreshortened, a curvilinear incision should be made between the anus and vagina; however, if the
perineum is of adequate length, a curved incision along the posterior
vaginal fourchette is associated with fewer wound healing problems.
e use of stay sutures or a Lone Star retractor (CooperSurgical, Inc.,
Trumbull, Conn.) to retract wound edges is helpful.
Once the incision is made, sharp dissection is required to elevate
anorectal and vaginal mucosa from the sphincter complex and associated scar. is process is technically the most dicult part of the procedure, and care is required to avoid “buttonholing” the rectal mucosa.
e scar and sphincter mechanism are dissected laterally to the midcoronal line to a sucient degree to allow overlap of the sphincter ends
in the midline. When possible, the IAS should be separately identied
and repaired. Excessive posterolateral dissection should be avoided
because branches of the pudendal nerve are found in the 3 and 9
o’clock positions and may be damaged inadvertently. Cephalad dissection in the rectovaginal septum continues until the levator ani muscles
are identied where they insert along the “white line” on the obturator
internus muscle on each side. In cases in which the sphincter muscles
are dicult to identify, it is usually possible to identify healthy sphincter in the ischiorectal fossa, away from the area of maximal scarring
in the anterior midline, and dissect medially. In most instances, an
overlapping sphincteroplasty, as described by Parks, is preferred. e
attenuated muscle and scar are divided (preserving the scar to help
prevent the suture from tearing through the muscle) and overlapped
to recreate a snug anal canal (Fig. 19-1). e repair is then performed
with a series of absorbable horizontal mattress sutures. Many surgeons
also perform an anterior levatorplasty in an eort to lengthen the anal
canal; however, it is a potential cause of dyspareunia.
Occasionally, the area of sphincter injury may show only thinning rather than a complete disruption. Under these circumstances,
some surgeons prefer to simply plicate the muscle rather than divide
it and overlap the ends. Data supporting this approach are limited.
e key to a good outcome is to create a high-pressure zone in
the anus of 2 cm or longer, and thus repair in depth is important.
lostomy or other fecal diversion is not necessary for the great
A co
majority of sphincter repairs but may be considered under special
circumstances, such as the failure of previous repair eorts.
One important aspect of sphincter repair aer obstetric injury is
re-creation of an adequate perineal body. For routine repairs, vertical
closure of the anterior portion of the incision is generally adequate.
When more severe injuries are present—for example, with a complete
cloacal defect—additional skin can be brought into the area through
use of a cruciate incision followed by a Z-plasty closure. Depending
on the extent of dissection in the rectovaginal septum, many surgeons
insert a closed suction drain and vaginal pack that may be removed
the following morning. In this circumstance, a urinary catheter also
should be inserted at the end of the procedure.
Postoperative management aer sphincter repair varies considerably among surgeons. Narcotic analgesic medications are needed and
RECTAL AND PARARECTAL REGION
95
B
A
C
re best delivered in the postoperative period either by epidural catheter
a
or patient-controlled analgesia pump. A regular diet may be resumed
and laxatives are prescribed to avoid constipation or fecal impaction in
the early postoperative period. Most patients are able to be discharged
on the second postoperative morning. Some surgeons instruct their
patients to perform a daily tap-water enema for the rst month aer
surgery; at a minimum, patients should be instructed to perform an
enema in the absence of a spontaneous daily bowel movement.
Between 60% to 80% of patients can expect a good or excellent
result aer sphincter repair, although minor defects in control, such
as leakage of gas or mild seepage, are common. However, continence
may deteriorate over time. Adverse prognostic factors include multiple previous failed repairs, severe preoperative incontinence (to solid
versus liquid stool), and possibly pudendal neuropathy.
Postanal Repair
Parks devised a postanal repair for patients with anatomically intact but
poorly functioning anal sphincters. e goals of the operation are to
lengthen and narrow the anal canal and provide a more acute anorectal
angle. e procedure is accomplished via a posterior intersphincteric dissection and is carried above the rectosacral fascia, which provides access
to plicate the puborectalis and external anal sphincter. Results of this procedure have been variable, and evidence suggests that function continues
to deteriorate aer surgery. e operation is now rarely performed.
Anal Encirclement
iersch described the rst anal encirclement procedure for rectal
prolapse in 1891. e principle of the technique is to tighten the anal
orice with use of a simple subcutaneous suture. During the past 50
years a large number of alternative “sutures” have been described,
ranging from wire to synthetic suture to various forms of silicone rubber. More recently, dynamic devices have been developed that allow
relaxation of the anal canal to facilitate defecation. e articial bowel
sphincter (ABS) consists of three components: an inatable cu, a
pressure-regulating balloon reservoir, and a patient-activated control
FIGURE 19-1
anal sphincter (A).
mattress sutures complete the repair (C). (From
Fazio VW, Church JM, Delaney CP, eds. Current
Therapy of Colon and Rectal Surgery. 2nd ed.
Philadelphia: Elsevier Mosby; 2005.)
Mobilization of the external
Overlap (B) and horizontal
pump. An appropriately sized cu is selected and positioned outside
the EAS. e balloon is implanted in the space of Retzius by means
of a short Pfannenstiel incision. e pump is positioned in the labia
majora in women and in the scrotum in men. e system is lled with
radiopaque uid, and its components are connected to one another by
tubing. e cu is le in a deated position postoperatively through
use of a deactivating button on the control pump. Provided healing
is complete, the cu is activated aer 6 weeks, and under normal circumstances the cu is inated. When the patient wishes to defecate,
he or she pumps the uid from the cu. e cu spontaneously rells
from the pressure-regulating balloon over 7 to 10 minutes.
e ABS has been used with some success; however, device erosion and outlet obstruction have proven to be dicult problems. A
magnetic anal sphincter has been developed that consists of approximately 20 individual magnetic beads linked by titanium wires that
allow distraction of the magnets when pressure is applied to the anal
canal during defecatory eorts (Fig. 19-2). Early results are promising, but device erosion can occur, and longer term data are awaited.
Muscle Transposition
Transposition of the gracilis muscle to encircle the anal canal as a
treatment for fecal incontinence was described by Pickrell in 1952.
Although the transposed muscle was meant to serve as a replacement sphincter, functional results proved to be poor. Augmentation
of “neosphincter” function can be obtained by electrical stimulation
of the obturator nerve because it supplies the gracilis muscle, and a
stimulated gracilis neosphincter remains a useful option in patients
who have lost considerable bulk of the sphincter mechanism, most
oen as a consequence of perineal trauma.
Sacral Ner
l nerve stimulation (SNS) is a novel approach to the treatment of
Sacra
ve Stimulation
fecal incontinence. is technique is similar to that used in urology practice to treat voiding dysfunction, with reports of considerable success.
96
FIGURE 19-2
magnetic anal sphincter after inser
P
atients undergo acute percutaneous nerve testing to conrm pelvic
oor contraction and to identify the optimal site of stimulation. e
optimal site of stimulation causes maximal pelvic oor contraction with
minimal associated contraction of the leg and foot. Once this site is identied (most commonly S3), a temporary lead is secured in position and
the patient undergoes test stimulation with an external pulse generator.
If the incontinence improves by at least 50%, permanent lead implantation with subcutaneous attachment to an implantable pulse generator is
performed. Excellent functional outcomes with minimal morbidity have
been reported. Several studies have shown improved quality of life associated with SNS therapy.
e mechanism of action of SNS for improving fecal incontinence
is uncertain; however, data suggest augmentation of sensory aerent
pathways and possibly normalizing colonic transit. In this regard,
SNS has also been shown to reduce colonic transit time in patients
with intractable constipation. e long-term results of SNS are excellent without apparent loss of ecacy. Some patients require device
reprogramming, perhaps because of tissue reaction around the electrodes; however, in most patients, diculties arise only when the battery life expires aer 6 to 8 years. Device replacement is relatively
simple. It remains unclear whether SNS or anal sphincteroplasty
should be the initial treatment of patients with EAS defects; however, most surgeons recommend sphincter repair for defects aecting
more than 25% of the sphincter.
osterior Tibial Nerve Stimulation
P
A
s with sacral neuromodulation, posterior tibial nerve stimulation
has been used by urologists to treat urinary incontinence. Recently,
the technique has been investigated with regard to treatment of
fecal incontinence. To date, eight studies using dierent neuromodulatory protocols have been published. Short-term successes
range from 30% to 83%. e advantages compared with SNS are
that it is minimally invasive and potentially more cost-eective.
However, the recent CONFIDeNT multicenter placebo controlled
trial of a 12 week course of posterior tibial nerve stimulation found
no signicant benet over sham stimulation.
Fec
al Incont
Intraoperativ
e radiograph showing the position of a
Inence
tion.
Continence Enemas
C
ontinence enemas have long been the standard means of managing
continence in patients with spinal cord defects that result in constipation and spurious incontinence. Malone developed the antegrade
continence enema procedure for children, particularly those with
spina bida. In adults, various ileal and colonic access conduits have
been devised; however, the problem of stomal stenosis and access difculties aect all of them. Retrograde continence enema techniques
can be very successful in motivated patients with spinal cord defects,
multiple sclerosis, or diabetic neuropathy for whom SNS or antegrade
continence enema have proven ineective.
Stem Cells, Bulking Agents, and Other Techniques
n a number of studies, autologous myoblasts and broblasts have been
I
injected into the urinary sphincter for the treatment of stress urinary
incontinence with mixed results. Shak was the rst to explore the use of
autologous fat cells injected into the external anal sphincter. More recent
studies have used fat- and muscle-derived stem cells in the treatment of
anal incontinence. Over the short term, results show modest improvements, and longer term data are awaited. e use of injectable nonbiodegradable bulking agents has been disappointing because the ideal agent
should be nonreactive, remain in situ, be easy to inject, and be costeective. To date, only one randomized trial of dextranomer in stabilized hyaluronic acid (Solesta, Q-Med AB, Uppsala, Sweden) has shown
promise. Recently a thin, solid, polyacrylonitrile cylinder has been developed (the Gatekeeper, THD, Correggio, Italy). Four to six of these cylinders are inserted into the intersphincteric plane, and within 24 hours
they become thicker and shorter, with resultant narrowing of the anal
canal. Again, long-term results are awaited. Finally, the SECCA device
(CJ Medical, Tresilian, Truro, United Kingdom), which uses radiofrequency energy to cause brosis in the anal canal, has been reported to
improve continence. Long-term results with the procedure and comparative studies are required before its eectiveness can be judged.
Fecal Diversion
Patients with severe fecal incontinence who have no therapeutic
options should be strongly encouraged to consider a stoma. However,
many patients, sometimes including those with debilitating symptoms, are reluctant to even consider this option. e argument to be
made is that of converting an unmanageable perineal stoma into a
manageable abdominal one. Patients have unlimited time to make this
decision, and referral to an enterostomal therapist, a patient who has
undergone an ostomy, or both is invaluable. Patients can predictably
expect to regain control of their bowel function and return to normal
function in society without the fear of embarrassing accidents.
For most patients, the appropriate choice of stoma is an endsigmoid colostomy. e stoma site should be marked preoperatively by
the enterostomal therapist, taking into consideration patient habitus,
scars, and other abdominal wall deformities. Patients with severe associated bowel dysfunction such as slow transit constipation may be better
served by an end-ileostomy. e procedure itself can be expeditiously
performed using a minilaparotomy, trocar procedure, or laparoscopic
techniques. It is important to counsel the patient that a defunctioned rectum may continue to produce mucus and that an interval proctectomy
might be needed to manage distressing ongoing leakage of mucus.
CONCLUSIONS
F
ecal incontinence is a distressing condition that is underreported
and undertreated. e cause of the incontinence dictates its therapy. Although the diagnosis is usually evident from the history and
Candidate for
surgery for FI
No immediate
surgical
indication
RECTAL AND PARARECTAL REGION
97
??
Biomaterial injection
Manometry, EMG, MRI, defecography
0–90° <180°
SNS
? MAS
hysical examination, appropriate investigation provides useful
p
Evaluation
EAUS ±
Sphincter
defect
Sphincteroplasty
conrmation and may uncover additional occult disease. Endoanal
ultrasonography plays a particularly important role in dening the
anatomy of both normal and disrupted anal sphincters.
e treatment of incontinence depends both on its cause and its
severity. Mild incontinence is best treated by conservative management
and sometimes biofeedback. Direct anal sphincter repair is indicated
for more severe incontinence when an anatomic sphincter defect is
present. When standard therapy is not appropriate or has failed, SNS
should be considered (Fig. 19-3). Use of an ABS device or magnetic anal
sphincter is an option when other modalities have failed. Continence
enemas are useful, particularly when other modalities of treatment have
failed or are deemed inappropriate. e role of injectable agents and
other novel therapies remains to be established. Experience with the
use of a gracilis neosphincter is limited, but the operation is of value
particularly in patients with perineal tissue loss. Fecal diversion remains
an excellent solution for the incontinent patient who is not a candidate
for standard or salvage therapy or for whom these therapies have failed.
u
S
Engel AF, Kamm MA, Sultan AH, etal. Anterior anal sphincter repair in pa-
Findlay JM, Maxwell-Armstrong C. Posterior tibial nerve stimulation and fae-
S t
g g e
tients with obstetric trauma. Br J Surg. 1994;81:1231–1234.
cal incontinence: a review. Int J Colorectal Dis. 2011;26(3):265–273.
e d
R
e
a d i n g
S
SECCA
>180° or
perineal tissue loss
FIGURE 19-3
Individualized treatment:
• Muscle transpostion
• Artificial sphincter/MAS
• ACE
• Colostomy
• Conservative therapy
Glasgow SC, Lowry AC. Long-term outcomes of anal sphincter re-
pair for fecal incontinence: a systematic review. Dis Colon Rectum.
2012;55:482–490.
Knowles CH, Horrocks EJ, Bremner SA, etal. Percutaneous tibial nerve stimu-
lation versus sham electrical stimulation for the treatment of faecal incontinence in adults (CONFIDeNT): a double-blind, multicentre, pragmatic,
parallel-group, randomised controlled trial. Lancet. 2015;386:1640–8.
Norton C, Kamm MA. Anal sphincter biofeedback and pelvic oor exercises
for faecal incontinence in adults—a systematic review. Aliment Pharmacol
er. 2001;15:1147–1154.
Ratto C, Parello A, Donisi L, etal. Novel bulking agent for faecal incontinence.
Br J Surg. 2011;98:1644–1652.
Rockwood TH, Church JM, Fleshman JW, etal. Fecal Incontinence Quality of
Life Scale: quality of life instrument for patients with fecal incontinence.
Dis Colon Rectum. 2000;43:9–16.
Tan E, Ngo NT, Darzi A, etal. Meta-analysis: sacral nerve stimulation versus
conservative therapy in the treatment of faecal incontinence. Int J Colorectal
Dis. 2011;26:275–294.
in NN, Horrocks EJ, Hotouras A, et al. Systematic review of the clinical
eectiveness of neuromodulation in the treatment of faecal incontinence.
Br J Surg. 2013;100:1430–1447.
Vaizey CJ. Faecal incontinence: standardizing outcome measures. Colorectal
Dis. 2014;16:156–158.
Wong MT, Meurette G, Wyart V, etal. e articial bowel sphincter: a single
institution experience over a decade. Ann Surg. 2011;254:951–956.
operativ
incontinence (FI). ACE, Antegrade
continence enema; EAUS, endoanal
ultrasound; EMG, electromyography;
MAS, magnetic anal sphincter; MRI,
magnetic resonance imaging; SNS,
sacral nerve stimulation.
Alg
orithm for
e treatment of fecal
R
S:
E
M
William Sangster and Da
vid B. Stewart, Sr.
DEFINITION
ectal stricture, or stenosis, is a pathologic narrowing or constriction
A r
involving the lumen of the rectum. is narrowing can be the result of
an intrinsic process that is occurring within the lumen or wall of the
rectum, or it can be secondary to an extrinsic process compressing the
rectum. A “clinically relevant” rectal stricture is one that is symptomatic and not easily dened by measurement of the diameter. However,
the condition frequently has been illustrated in terms of the inability to
traverse the aected cross-section of rectum with either a rigid proctoscope (12 mm diameter) or a rigid sigmoidoscope (19 mm diameter).
PRESENT
S
ymptomatic rectal strictures cause obstructive symptoms such as
a gradual change in stool caliber or consistency, anorectal bleeding, tenesmus, or abdominal distention and discomfort that is oen
exacerbated by eating. Some symptomatic rectal strictures that are
not treated will eventually cause a complete large bowel obstruction,
especially those associated with inammatory bowel disease (IBD),
malignancy, and radiation-induced proctitis.
e diagnosis of a rectal stricture is based on history, physical
examination, and, occasionally, imaging ndings. e degree of a stenosis is best imaged with a water-soluble contrast enema. Computed
tomography and magnetic resonance imaging, with or without rectal
contrast enhancement, can be helpful in assessing other segments of
the alimentary tract or the peritoneal cavity for conditions such as
IBD and cancer.
ATION AND DIAGNOSIS
stricture that has been found incidentally. All strictures require assessment before it is safe to recommend observation. e rst step in the
assessment is to exclude malignancy. Multiple biopsies, as well as imaging with endorectal ultrasound, computed tomography, and magnetic
resonance imaging, are usually required to exclude cancer. All strictures
should be described in terms of their diameter, their distance from the
anal verge, and their length, because shorter strictures are more amenable to endoscopic dilatation than are longer benign strictures, which
are more likely to require either diversion or resection.
For distal rectal strictures (those <6 cm from the anal verge), dilation can be performed digitally or with the assistance of instruments,
such as Hegar dilators. Hegar dilators are quite useful because they
come in multiple sizes with graded diameters, allowing a gradual
dilation that provides a measure of safety against perforation. For
more proximal strictures, dilatation with a rigid proctoscope or
endoscopic balloon is an option. e success rate of endoscopic dilation is variable (88% to 100%) and depends on several factors, including stricture location (>8 cm from the anal verge being preferable), a
shorter stricture (<1 cm), and the absence of any previous radiotherapy. As with Hegar dilators, pneumatic dilatation provides a choice of
instruments to accommodate almost any stricture. When pneumatic
dilation fails, other techniques include endoscopic electroincision of
the stricture or endoscopic stent placement. Currently, stent placement for the treatment of benign rectal strictures has only been used
in an o-label manner, and it is not approved by the Food and Drug
Administration in the United States because of high rates of stent
migration. If a stricture cannot be managed endoscopically, resection
or fecal diversion is required.
ETIOLOGY
S
trictures of the rectum may develop as a result of multiple causes that
can be broadly categorized as benign and malignant. ese causes are
listed in Table 20-1. Management depends on the cause of the stric-
ture, its distance from the anal verge, and the degree of stenosis.
BENIGN RECTAL STRICTURES
lthough a variety of benign diseases can produce a rectal stricture,
A
most benign strictures are due to an ischemic colorectal anastomosis
or IBD. Benign rectal strictures do not need to be treated unless they
are symptomatic, at which point several options are available, depending on the nature and severity of the stricture (Fig. 20-1). Patients may
be referred to a colorectal surgeon because an unexpected stricture is
discovered during a colonoscopy. It is vital that the surgeon understand the dierence between a stricture that requires treatment and a
98
Rectal Strictur
Disease
lthough rectal strictures related to IBD are usually benign, they are
A
oen dicult to manage and thus warrant a separate discussion.
A rectal stricture in Crohn disease has been, and continues to
be, a predictor of poor outcome, especially in terms of avoiding a
permanent stoma. It has been suggested that the formation of rectal strictures in persons with Crohn disease is frequently associated
with active disease involving both the rectum and anus, which confers
a low probability of preserving per-anal defecation. Patients with a
rectal stricture due to Crohn-related proctitis may require multiple
surgeries, such as resection with a diverting stoma followed by subsequent closure of the stoma, or, more commonly, an urgent resection
to address a large bowel obstruction followed by an elective completion proctectomy.
In an eort to avoid a resection and a likely permanent stoma,
endoscopic balloon dilation has been attempted. For Crohn-related
strictures, balloon dilation has a 60% to 70% success rate as dened by
es Related to Inflammatory Bowel
TABLE 20-1: Etiology of Rectal Strictures
Benign Malignant
nastomotic stricture Primary rectal cancer
A
Inammatory bowel disease (e.g.,
Crohn disease/ulcerative colitis)
Radiation Ovarian cancer
Ischemia Prostate cancer
Penetrating injury/foreign
body trauma
Caustic injury Sarcoma
Endometriosis
Pelvic abscess
exually transmitted infections (e.g.,
S
lymphogranuloma venereum)
T
uberculosis
Recurrent rectal cancer
Lymphoma
RECTAL AND PARARECTAL REGION
ean symptom-free interval of 12 to 18 months aer one dilation.
a m
99
However, balloon dilation has a high rate of perforation (approximately 10%), sometimes with devastating consequences. To improve
outcomes, some persons have suggested injecting corticosteroids
directly into the area of the stricture in conjunction with dilation
as a means of impeding collagen cross-linking and theoretically to
decrease brosis aer dilation. However, intramural steroid injection
was not demonstrated to improve outcomes in a randomized trial
by East etal, and thus currently this use of steroids is not a routine
practice. In the case of long-standing Crohn-related rectal strictures,
biopsies should always be performed to exclude malignancy. Lengthy
strictures and those with a greater severity and greater degree of distortion of the rectal wall are more likely to require surgical resection,
as are strictures with early and frequent recurrence aer endoscopic
dilation.
For rectal strictures that occur in the setting of ulcerative colitis,
management options are limited and tend to favor surgical resection,
especially considering that removal of the rectum and colon is a cure
for this form of IBD. Although rectal strictures related to ulcerative
colitis have more frequently been shown to be benign than malignant, several scenarios exist in which the diagnosis of malignancy
should be especially strongly considered. It has been estimated that
if a stricture develops late in the course of the disease (aer approximately 20 years), the probability of the stricture being malignant is
as high as 61%. It has also been observed that if the stricture results
Benign anastomotic stricture
Asymptomatic Symptomatic
Monitor
<6 cm from anal verge
Digital/Hegar dilation
Surgical candidate
Recurrent symptomsSuccessful
Re-dilateMonitor Monitor
Recurrent symptoms
>6 cm from anal verge
Rigid proctoscope dilation/
endoscopic balloon dilation
Successful
Unsuitable for surgery
FIGURE 20-1 T
Resection versus stoma
reatment algorithm for benign rectal anastomotic strictures.
Endoscopic stent
placement or other
endoscopic therapy
100
Rect
RictuRe: etiology
al St
and Manage
Malignant Rectal Stricture
Ment
Surgical candidate
Excision ±
neoadjuvant or
adjuvant therapy
FIGURE 20-2
Decompression Palliation
Endoscopic self-expanding
metal stent placement
± (Chemo)radiotherapy
Surgical excision?
T
reatment algorithm for malignant rectal strictures.
in symptoms of a large bowel obstruction, the probability of the
stricture being malignant is virtually 100%. Considering that there
is a putative surgical cure for ulcerative colitis, and considering the
diculties associated with false-negative biopsies of strictures that
occur in the setting of ulcerative proctitis, surgical resection should
be performed unless the patient is not a candidate for the procedure.
Whether that surgery should entail a restorative proctocolectomy or
a permanent ileostomy is a complex decision, because the presence of
a malignancy in the rectum may warrant the use of radiotherapy, with
its potential impact on an ileal pouch–anal anastomosis.
MALIGNANT RECT
alignant strictures of the rectum are most commonly, and most
M
AL STRICTURES
appropriately, treated with surgical resection. Choices among surgical options include anterior or low anterior resections, an abdominoperineal resection, or local excision through a transanal approach
(Fig. 20-2). e choice of surgery depends on the size and clinical
stage of the cancer, its distance from the anal verge, and the general
health of the patient. In general, the endoscopic treatment of malignant colorectal strictures has been used in two clinical scenarios:
preoperative decompression as a bridge to surgery, and endoscopic
decompression for palliation in scenarios in which surgery is not
feasible. Endoscopic modalities currently center on self-expanding
metal stents and endoscopic laser therapies.
Self-expanding metal stents have been approved for use both in
palliation and for preoperative decompression, which, in the latter
instance, can serve to convert an indication for urgent surgery into
a more elective scenario. Decompression permits mechanical preparation of the large intestine and therefore the potential for avoiding
the creation of a stoma. Endoscopic stents are composed of a variety
of metal alloys and currently come in varying sizes. Successful stent
deployment with improvement in the degree of colonic distention
has been demonstrated in up to 80% to 90% of patients, based on the
current literature. Stents for proximal rectal strictures appear to be
tolerated better than stents for distal rectal strictures because stents
placed distally in the rectum may produce tenesmus, rectal pain,
and fecal incontinence. Perforation is the most serious complication of endoscopic stenting within the rectum and has been observed
to occur at a rate of 5% to 10%. In minor cases, perforation can be
Unsuitable for surgery/
does not desire diversion
Endoscopic self-expanding
metal stent placement or
laser therapy
(Chemo)radiotherapy
or monitor
managed with bowel rest and parenteral antibiotics. Larger perforations may require emergency surgery. e reported stent migration
rate and stent occlusion rate due to tumor ingrowth or fecal impaction is variable, ranging from 3% to 30%. If obstructive symptoms
recur as a result of stent migration or tumor ingrowth, placement of a
second stent is an option. Although no set guidelines exist regarding
the length of time that an endoscopically placed rectal stent can be
safely le in situ, reports have been made of stents remaining in place
for up to 5 years without complications.
Laser therapy, which has been utilized for decades, has been
found to be most useful in the palliation of obstructions caused by
bulky, exophytic tumors. Overall, laser therapy has been shown to
achieve successful palliation in 80% to 90% of cases in which it has
been used. However, an average of approximately three procedures is
required to achieve sucient relief of obstructive symptoms. erefore, some persons are attempting to transition to argon beam plasma
coagulation, which has been reported to produce results similar to
laser therapy. ese results have yet to be conrmed.
SUMMAR
e management of rectal strictures varies according to their eti-
Th
Y
ology, severity, location, and the health status of the patient. After
asymptomatic strictures have been evaluated to exclude cancer,
they should be monitored but not necessarily treated. Symptomatic rectal strictures can be treated endoscopically by dilation or
incision, and if these techniques fail, by resection or diversion.
Malignant strictures are resected or palliated with use of radiation, stenting, or debulking.
S
u
g g e
B
aron TH. Colonic stenting: technique, technology, and outcomes for
malignant and benign disease. Gastrointest Endosc Clin North Am.
2005;15(4):757–771.
East JE, Brooker JC, Rutter MD, etal. A pilot study of intrastricture steroid
versus placebo injection aer balloon dilatation of Crohn’s strictures. Clin
Gastroenterol Hepatol. 2007;5(9):1065–1069.
Fields S, Rosainz L, Korelitz BI, etal. Rectal strictures in Crohn’s dis-
ease and coexisting perirectal complications. Inflamm Bowel Dis.
2008;14(1):29–31.
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