imperforate anus and cloacal malformations
TRANSCRIPT
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History case
A child was born in term after normal pregnancy and delivery with
body weight at birth of 3000 gr.
The condition after birth is satisfactory.
The pathologies of heart and lungs have not been determined.
The abdomen is soft and slightly distended.
On the examination of perineum the absence of anal orifice wasattested.
On the medial line the cutaneous protuberance and ischial tuberosity
are converging.
The peritoneum irritation signs are negative.
The child is 1 day old.
Blood analyzespH 7,32; pCO2 36 mmHg; BE - -4; Hb 220 g/l; Ht
65%.
What are the presumptive diagnosis, investigation plan and
treatment tactics?
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History case
Cross-table X-ray with Hagar dilator in anal canal
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Anorectal malformations
Jalba Alexandru,
MD, PhD,
associate professor
Chisinau 2012
N. Testemitanu State University of Medicine and Pharmacy
Department of Pediatric Surgery, Orthopedics and Anesthesiology
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Imperforate anus and cloacalmalformations
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Background
o Imperforateanushas been a well-known condition since antiquity. For
many centuries, physicians, as well as individuals who practicedmedicine, tried to help these children by creating an orifice in the
perineum. Many patients survived, most likely because they suffered
from a type of defect that is now recognized as low. Those with a
highdefect did not survive treatment.
o In 1835, Amussat was the first to suture the rectal wall to the skin edges,
which could be considered the first actual anoplasty.
o During the first 60 years of the 20th century, most surgeons performed a
perineal anoplasty without a colostomy for the so-called low
malformations.
o In 1953, Stephens proposed an initial sacral approach followed by an
abdominoperineal operation, if necessary.
o The posterior sagittal approach for the treatment of imperforate anus was
performed first in 1980, and its description was published in 1982.
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Incidence, types of defects,
and terminology
o Anorectal atresia occurs in one of every 4000 to 5000 newborns and isslightly more common in males.
o The estimated risk for a couple having a second child with an anorectal
malformation is approximately 1%.
o The most frequent defect in male patients is anorectal atresia with a
rectourethral fistula, and is anorectal atresia with a rectovestibular fistulain females.
o Imperforate anus without a fistula is a rather unusual defect. It occurs in
about 5% of the entire group of malformations, and is associated with
Down syndrome.
o Historically, persistent cloaca was considered an unusual defect, whereasa high incidence of rectovaginal fistula was reported in the literature. It is
likely that most patients suffering from a persistent cloaca were
erroneously thought to have a rectovaginal fistula. Many of these patients
underwent surgery with repair of the rectal component but were left with a
persistent urogenital sinus.
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Embriology
The rectum and anus are believed to develop from the dorsal potion of the hindgut or cloacal cavity when
lateral ingrowth of the mesenchyme forms the urorectal septum in the midline. This septum separates the
rectum and anal canal dorsally from the bladder and urethra. Downgrowth of the urorectal septum is believed
to close this duct by 7 weeks' gestation. During this time, the ventral urogenital portion acquires an external
opening; the dorsal anal membrane opens later.
The anus develops by a fusion of the anal tubercles and an external invagination, known as the proctodeum,
which deepens toward the rectum but is separated from it by the anal membrane. This separating membraneshould disintegrate at 8 weeks' gestation.
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Embriology
Interference with anorectal structure development at varying stages leads to
various anomalies, ranging from anal stenosis, incomplete rupture of the anal
membrane, or anal agenesis to complete failure of the upper portion of the
cloaca to descend and failure of the proctodeum to invaginate. Continuedcommunication between the urogenital tract and rectal portions of the cloacal
plate causes rectourethral fistulas or rectovestibular fistulas.
The external anal sphincter, derived from exterior mesoderm, is usually
present but has varying degrees of formation, ranging from robust muscle
(perineal or vestibular fistula) to virtually no muscle (complex longcommon-
channel cloaca, prostatic or bladder-neck fistula).
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Classification
Anorectal malformations represent a wide spectrum of defects.
The terms low,intermediate,and highare arbitrary and not useful
in therapeutic or prognostic terms.
Within the group of anorectal malformations traditionally referred to ashigh, there are defects included with different therapeutic and
prognostic implications. For instance, retroprostatic fistula and recto-
bladder neck fistula were both considered high, yet the first can be
repaired with a posterior sagittal approach alone and the second requiresan additional abdominal approach. Furthermore, the prognosis for each
type is completely different. Therefore, a more therapeutic and
prognostically oriented classification is depicted on the slide below.
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Classification
Males Cutaneous (perineal fistula)
Rectourethral fistula
Bulbar
Prostatic
Rectobladder neck fistula Imperforate anus without fistula
Rectal atresia
Females
Cutaneous (perineal fistula)
Vestibular fistula
Imperforate anus without fistula
Rectal atresia
Cloaca
Complex malformations
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MALE
ANORECTAL DEFECTS
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Rectoperineal fistulas
Rectoperineal fistula is what traditionally was known as a low
defect. The rectum is located within most of the sphincter
mechanism. Only the lowest part of the rectum is anteriorly
mislocated (Fig. 1, 2).
Sometimes, the fistula does not open into the perineum but ratherfollows a subepithelial midline tract, opening somewhere along the
midline perineal raphe, scrotum, or even at the base of the penis. This
diagnosis is established by perineal inspection. No further
investigations are required. Usually, the anal fistula opening is narrow
(stenotic).
The terms covered anus, anal membrane, anteriorly mislocated anus,
and bucket - handle malformations all refer to perineal fistulas.
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Rectoperineal fistulas
Figure 1.This drawing shows the course of aperineal fistula in a male. The rectum is locatedwithin most of the muscle complex. Only the
most distal aspect of the rectum is misplaced
Figure 2.Newborn with imperforate anus and arectoperineal fistula.
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Rectourethral fistulas
Imperforate anus with a rectourethral fistula is the most frequent
defect in male patients. The fistula may be located at the lower(bulbar) (see figure 3A) or the higher (prostatic) part of the urethra
(see figure 3B).
A B
Figure 3. Anorectal atresia with rectourethral fistulas.
A, Rectourethrobulbar fistula B, Rectourethroprostatic fistula
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Rectourethral Fistulas
Immediately above the fistula, the rectum and urethra share a common
wall.
The lower the fistula, the longer is the common wall. This is an
important anatomic fact with significant technical and surgical
implications.
The rectum is usually distended and surrounded laterally and
posteriorly by the levator muscle. Between the rectum and the perineal
skin, a portion of striated voluntary muscle called the muscle complex
is present. The contraction of these muscle fibers elevates the skin of
the anal dimple. At the level of the skin, a group of voluntary muscle
fibers, called parasagittal fibers, are located on both sides of the
midline.
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Rectourethral Fistulas
Lower urethral fistulas are usually associated with good-quality
muscles, a well-developed sacrum, a prominent midline groove, and a
prominent anal dimple.
Higher urethral fistulas are more frequently associated with poor-
quality muscles, an abnormally developed sacrum, a flat perineum, a
poor midline groove, and a barely visible anal dimple.
Of course, exceptions to these rules exist. Occasionally, the infant
passes meconium through the urethra, which is an unequivocal sign of
a rectourinary fistula.
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Recto-Bladder Neck Fistulas
In this defect, the rectum opens into the bladder neck (Fig. 4).
The patient usually has a poor prognosis for bowel control because the
levator muscles, the striated muscle complex, and the external
sphincter frequently are poorly developed.
The sacrum is often deformed and short. In fact, the entire pelvis
seems to be underdeveloped.
The perineum is often flat, which is evidence of poor muscle
development. About 10% of males with anorectal atresia fall into this category.
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Recto-Bladder Neck Fistulas
Figure 4.Schematic representation of
a recto-bladder neck fistula. Note that
the fistula enters into the bladder neck
near the junction between the urethra
and the bladder.
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Imperforate Anus without Fistula
Interestingly, most patients with imperforate anus without fistula
(Fig.5) have a well-developed sacrum and good muscles, and have a
good prognosis in terms of bowel function.
The rectum usually terminates approximately 2 cm from the perineal
skin.
Although the rectum and urethra do not communicate, these two
structures are separated only by a thin, common wall.
About half of the patients with no fistula also have Down syndrome,
and more than 90% of patients with Down syndrome and imperforate
anus have this specific defect, suggesting a chromosomal link.
The fact that these patients have Down syndrome does not seem to
interfere with their good prognosis for bowel control.
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Imperforate Anus without Fistula
Figure 5. A boy with imperforate anus
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Rectal Atresia
In this extremely unusual defect in male patients (~1% of the entire group
of malformations), the lumen of the rectum is totally (atresia) or partially(stenosis) interrupted. The upper pouch is represented by a dilated rectum,
whereas the lower portion is represented by a small anal canal that is in the
normal location and is 1 to 2 cm deep (Fig. 6).
Figure 6.This newborn was found to have rectal atresia. A,Note the normal anal positionand short depth of the anal canal. B, Operative repair. A dilator has been inserted into theanus and the anastomosis (arrow) is identified just proximal to the distal anal canal.
A B
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Rectal Atresia
These two structures may be separated by a thin membrane or by
dense fibrous tissue.
The repair involves a primary anastomosis between the upper pouch
and anal canal (see Fig. 6B) and is ideally approached posterior
sagittally.
Patients with this defect have all the necessary elements to be
continent and have an excellent functional prognosis.
Because they have a well-developed anal canal, they have normal
sensation in the anorectum and have almost normal voluntarysphincters. Patients with rectal atresia must be screened for a presacral
mass.
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FEMALE
ANORECTAL DEFECTS
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Rectoperineal Fistulas
From the therapeutic and prognostic viewpoint, this common defect is
equivalent to the perineal fistula described in the male patient.
The rectum is well positioned within the sphincter mechanism, except
for its lower portion, which is anteriorly located.
The rectum and vagina are well separated (Fig. 7).
The key anatomic issues are the anal opening in relation to the
sphincter mechanism, and the length of the perineal body.
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Rectoperineal Fistulas
Figure 7. Schematic representation of a recto-bladder neck fistula. Note that the fistula
enters into the bladder neck near the junction between the urethra and the bladder.
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Rectovestibular Fistulas
Rectovestibular fistula is the most common defect in girls and has anexcellent functional prognosis. The diagnosis is based on clinical
examination. A meticulous inspection of the neonatal genitalia allows the
clinician to observe a normal urethral meatus and a normal vagina, with a
third hole in the vestibule, which is the rectovestibular fistula (Fig. 8).
About 5% of these patients will have two hemivaginas with a vaginal
septum.
A number of pediatric surgeons repair this defect without a protective
colostomy. This is a well- recognized trend in the management of
anorectal malformations. The advantage of this approach isthat it avoidsthe potential morbidity of a colostomy and reduces the number of
operations to one from as many as three (colostomy, main repair, and
colostomy closure).
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Rectovestibular Fistulas
Figure 8. A, Schematic drawing of a rectovestibular fistula. B, A female neonate with arectovestibular fistula. Note the patient is in the prone position and the rectal fistula(arrow) is located in the posterior aspect of the vestibule.
A B
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FOURCHETTEFISTULA
If perineal fistula is not identified,
the labia are separated to search for
a vestibular fistula. A Fourchette
fistula is a type of vestibular fistula
that straddles the spectrum of
malformation between perineal andvestibular; it is characterized by
wet mucosa of the vestibule
anteriorly and a dry anoderm
posteriorly at the junction of the
vestibule and perineum (see the
image).
Figure 9. Fourchette fistula. This malformation issomewhere halfway between perineal fistula and vestibularfistula. The fistula has a wet vestibular mucosal lining on itsanterior half, but the posterior half is dry perineal skin.
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Rectovestibular Fistulas
Many patients do very well with a primary neonatal operation without a
protective colostomy.
However, a perineal infection followed by dehiscence of the anal
anastomosis or perineal body, or recurrence of the fistula provokes severe
fibrosis that may interfere with the sphincter function.
If these complications occur, the patient may have lost the best
opportunity for an optimal functional result because secondary operations
do not render the same prognosis as a successful primary operation.
Thus, a protective colostomy is still the best way to avoid these
complications.
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Rectovestibular Fistulas
The decision to perform a colostomy or primary repair in these cases must
be made individually by the surgeon, taking into consideration his or her
experience and the clinical condition of the patient.
In our AcademicianNatalia GheorghiuNational Scientific and Practical
Center of Pediatric Surgery, neonates born with this anomaly, without
significant associated defects, undergo operation without a colostomy.
The term vaginal fistula is frequently erroneously used in patients who
actually have a vestibular fistula or a cloaca. A true vaginal fistula occurs
in less than 1% of all cases and is not considered part of the proposed
classification.
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Imperforate Anus without Fistula
This defect in female patients (Fig. 10) carries the same therapeutic
and prognostic implications as described for male patients
Figure 10. A girl with imperforate anus
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Persistent Cloaca
This group of defects represents the extreme in the spectrum of complexity
of female malformations.
A cloaca is defined as a defect in which the rectum, vagina, and urinary
tract meet and fuse, creating a single common channel.
The diagnosis of persistent cloaca is a clinical one. This defect should be suspected in a female born with imperforate anus and
small-looking genitalia (Fig. 11).
Careful separation of the labia discloses a single perineal orifice.
The length of the common channel varies from 1 to 7 cm. This distance has
technical and prognostic implications. Common channels longer than 3 cmusually are associated with complex defects (Fig. 12 A).
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If no fistula is visible and only one opening between shortened labia is
observed, the child has a cloaca.
Figure 11. Cloaca. This is the classic appearance of a girl with a cloacalmalformation with a single perineal orifice. The genitals appear quite short,which is a finding consistent with cloaca.
Persistent Cloaca
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Persistent Cloaca
Figure 12A. Schematic diagram of a long common channelin a female with a cloacal anomaly.
o Mobilization of the
vagina is difficult in such
cases. Therefore, in patients
with a long common
channel, some form of
vaginal replacement is
often needed during the
definitive repair.
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Persistent Cloaca
A common channel of less than 3 cm usually means that the defect can be
repaired with a posterior sagittal operation without opening the abdomen(Fig, 12B).
Figure 12B. The more commonly encountered short common channel cloaca isdepicted.
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Persistent Cloaca
When the rectum opens high into the dome of the vagina (Fig. 13), an
abdominal approach must be utilized to mobilize the bowel.
Figure 13. A schematic diagram of the rectum inserting high into the posteriorvagina with a short common urethral and vaginal channel is shown.
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Persistent Cloaca
Frequently, the vagina is abnormally
distended and full of secretions(hydrocolpos) (Fig. 14).
The distended vagina compresses the
trigone and interferes with drainage of
the ureters and is frequently associated
with megaureters. This condition may be diagnosed
prenatally.
The dilated vagina can also become
infected (pyocolpos) and may lead to
perforation and peritonitis. However, such a large vagina may
represent a technical advantage for the
repair, providing more vaginal tissue
to facilitate the reconstruction.
Figure 14. Schematic depiction of a cloacalanomaly with insertion of the rectum into thecommon channel and subsequent vaginalobstruction with hydrocolpos.
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Persistent Cloaca
A frequent finding in cloacal
malformations is the presence ofdifferent degrees of vaginal and
uterine septation or duplication (see
Fig. 15).
The rectum usually enters between the
two hemivaginas. Rarely, patients may have cervical
atresia.
During puberty, they are unable to
drain menstrual blood through the
vagina. These patients accumulate menstrual
blood in the peritoneal cavity and
often require emergency operations
Figure 15. Schematic depiction of a cloacalanomaly and uterine duplication. The rectumis shown entering between the twohemivaginas.
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Persistent Cloaca
An evaluation of a patients Mullerian anatomy, either at the time of the
definitive repair or at the colostomy closure, is vital and can prevent future
problems.
Low cloacal malformations (
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COMPLEXMALFORMATIONS
Unusual and bizarre anatomic arrangements can be seen.
Each case represents a unique challenge to the surgeon, with different
prognoses and therapeutic implications.
No general guidelines can be drawn for the management of these patients.
Each case must be individualized.
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ASSOCIATED DEFECTS
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SACRUMANDSPINE
Sacral deformities appear to be the most frequently associated defect. Oneor several sacral vertebrae may be missing (Fig. 16).
A single missing vertebrae does not seem to have any important prognostic
implications.
However, more than two absent sacral vertebrae represent a poor
prognostic sign in terms of bowel continence and, sometimes, urinary
control.
A hemisacrum is usually associated with a presacral mass and poor bowel
control (Fig. 17).
Other sacral abnormalities, such as spinal hemivertebra, have a negativeimplication for apatientsbowel control.
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SACRUMANDSPINE
Figure 16. Sacral radiography (seethe picture) - Absent lumbosacralvertebrae, a severe vertebral anomaly.
Figure 17. Hemisacrum withpresacral mass.
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SACRUMANDSPINE
A sacral ratio allows for a more objective evaluation of the sacrum
(Fig.18). The normal sacral ratio in children is 0.77.
Children with anorectal malformations suffer from different degrees of
sacral hypodevelopment, and the sacral ratio can vary from 0.0 to 1.0.
We have never seen a patient develop good bowel control with a sacral
ratio of less than 0.3.
Figure 18. Drawings with landmarks necessary for the calculation of the sacral ratio. A, Lateral
view. B, Anteroposterior view. The normal ratio is 0.77.
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SACRUMANDSPINE
Emphasis has been placed on the diagnosis and treatment of a tethered cord(Fig. 19), which is a defect frequently associated with anorectal
malformations.
It has been assumed that the presence of a tethered cord is associated with
poor functional prognosis in these children.
A review of our own series showed that 25% of patients with an anorectal
malformation suffer from tethered cord.
Although it is true that most of these children have a poor prognosis, the
presence of a tethered cord by itself coincides with a very high defect, very
abnormal sacrum, or spina bifida.
Therefore, it is difficult to know whether the tethered cord itself is
responsible for the poor prognosis.
Also, we have not found evidence that the operation to release the tethered
cord changes the functional bowel prognosis of the patient.
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SACRUMANDSPINE
Figure 19. MRI. Tethered spinal cord
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GENITOURINARYDEFECTS
The frequency of associated genitourinary defects varies from 20% to54%.
The higher the malformation, the more frequent are the associated
urologic abnormalities.
Patients with persistent cloacas or recto-bladder neck fistulas have a 90%
chance of having an associated genitourinary abnormality (Fig. 20, 21).
Conversely, children with low defects (perineal fistulas) have less than a
10% chance of having an associated urologic defect.
Hydronephrosis (Fig. 22), urosepsis, and metabolic acidosis from poor
renal function represent the main sources of morbidity in infants with
anorectal malformations.
Thus, a thorough urologic investigation is mandatory in cases of high
defects, but is not as urgent in cases of rectovestibular and rectourethral
fistulas.
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GENITOURINARYDEFECTS
Figure 20.Voiding cystourethrography.
Vesicoureteral reflux.Figure 21. Voiding cystourethrography.
Neurogenic bladder
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GENITOURINARYDEFECTS
Figure 22. Ultrasonography demonstrating hydronephrosis in a
newborn with imperforate anus.
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NEWBORN MANAGEMENT
NEWBORN MANAGEMENT (MALE)
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NEWBORNMANAGEMENT(MALE)
A decision-making algorithm for the initial management in male patients is
seen in Fig. 23.
Newborn Male Anorectal Malformation
Perineal inspection
Spine
Kidney U/S
Urinalysis
R/O esophageal atresia
Re-evaluation and cross table lateral film
Perineal fistula Rectal gas belowcoccyx
No associated
defects
Rectal gas below coccyx
Associated defects
Abnormal sacrum
Flat bottom
Anoplasty Consider PSARPwith or without
colostmy
Colostomy
Sacrum
Spinal U/S
Cardiacecho20-24hours
Figure 23.Algorithm for the management of male newborns with anorectal malformationsbased on the physical examination and radiographs. PSARP, posterior sagittal anorectoplasty;
U/S, ultrasonography; R/O, rule out.
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NEWBORNMANAGEMENT(MALE)
During the past few years, the tendency by the pediatric surgical communityhas been to operate on patients with anorectal malformations primarily
without a protective colostomy.
However, to avoid the potential negative consequences, these operations
shouldnt be performed without the necessary preoperative evaluation and
experience. A thorough perineal inspection usually gives the key clues to the type of
malformation.
The decision about a colostomy or primary operation shouldnt be made
before 24 hours of life, because of the fact that significant pressure is needed
for the meconium passage through fistulous orifice, as well as radiologicfindings may not show the correct anatomy, because the rectum is collapsed.
During the first 24 hours, the neonate should receive intravenous fluids and
antibiotics and be evaluated for associated defects that may represent a threat
to life (cardiac malformations, esophageal atresia, and urinary defects).
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NEWBORNMANAGEMENT(MALE)
If the neonate has signs of a perineal fistula, we recommend that an
anoplasty, without a protective colostomy, be performed during the first48 hours of life.
After 24 hours, if there is no meconium on the perineum, we recommend
obtaining a cross-table lateral radiograph with the patient in the prone
position(Fig. 24) or invertography (Fig. 25) .
Figure 24.Technique for a cross-table lateral radiograph. A, A roll has been placed beneath the hips of theinfant to elevate the buttocks and allow air to migrate superiorly to the end of the rectum. B, Actual cross-table lateral radiograph. Air is visualized distal to the coccyx (arrow).
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NEWBORNMANAGEMENT(MALE)
If air in the rectum is located below the coccyx, (Fig. 24) and the patient is
in good condition with no significant associated defects, one may considerperforming a posterior sagittal operation without a protective
colostomy.
A more conservative alternative would be to perform the posterior
sagittal repair and a protective colostomyat the same stage.
Figure 24.Technique for a cross-table lateral radiograph. A, A roll has been placed beneath the hips of theinfant to elevate the buttocks and allow air to migrate superiorly to the end of the rectum. B, Actual cross-table lateral radiograph. Air is visualized distal to the coccyx (arrow).
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Invertography
Lateral pelvic radiography at
24 hours: Children who could
not be diagnosed based solely on
physical examination findings,
traditionally underwent
invertography, which consisted
of holding the baby upside down
and using lateral radiography to
observe the level of gas in thedistal rectum (Fig. 25).
Figure 25. Invertography
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NEWBORNMANAGEMENT(MALE)
Conversely, if the rectal gas does not extend beyond the coccyx, or the
patient has meconium in the urine, an abnormal sacrum, or a flat bottom, westrongly recommend a colostomy.
This allows for a future distal colostogram (Fig. 26), which will precisely
delineate the anatomy.
We would then perform a posterior sagittal anorectoplasty 1 to 2 months
later, provided the neonate is gaining weight appropriately.
Performing the definitive repair at age 1 to 3 months has important
advantages, including less time with an abdominal stoma, less size
discrepancy between the proximal and distal bowel at the time of colostomy
closure, and easier anal dilation (because the infant is smaller).
In addition, at least theoretically, placing the rectum in the right location
early in life may represent an advantage in terms of the potential for
acquired local sensation.
AUGMENTED PRESSURE DISTAL
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AUGMENTED-PRESSUREDISTAL
COLOSTOGRAPHY
o This is the single most important diagnostic test used to clarify theanatomy in all children with malformations who require colostomy.
o It is personally performed by the colorectal surgeon in many centers.
o In a fluoroscopy suite, a balloon catheter is placed into the distal stoma,
and the balloon is inflated.
o The catheter is pulled back, and water-soluble contrast is injected by hand.
o This pressure is required to overcome the pressure of the levator muscles
and to allow the contrast to flow into the lowest part of the colon and
reveal any fistula.
o In patients with a fistula to the urinary tract, the bladder often fills, and thestudy is continued to obtain as much information as is provided with
voiding cystourethrography.
o If no fistula is present, the distal pouch has a rounded appearance, and no
urinary extravasation is visible. (See the picture below Fig. 26)
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Figure 26. Augmented-pressure distal colostography demonstrating rectourethralfistula only when adequate pressure is used. Note the flat rectum on the left, whichrepresents compression of the distal rectum in the funnel-like sphincteric mechanism.
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NEWBORNMANAGEMENT(MALE)
However, all of these above mentioned potential advantages of an early
operation must be weighed against the possible disadvantages of aninexperienced surgeon who is not familiar with the minute anatomic
structures of an infantspelvis.
A temptation to repair these defects without a protective colostomy always
exists.
Repair without a colostomy limits the anatomic information (provided by a
distal colostogram) that may be very helpful to the surgeon.
The worst complications involve patients operated on without a colostomy
or a properly performed distal colostogram.
Proceeding with the posterior sagittal approach looking blindly for therectum has resulted in a spectrum of serious complications, including
damage to the urethra, complete division of the urethra, pull-through of the
urethra, pull-through of the bladder neck, injury to the ureters, and division
of the vas deferens or seminal vesicles.
NEWBORN MANAGEMENT (FEMALE)
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NEWBORNMANAGEMENT(FEMALE)
Figure 27. Decision-making algorithm for female newborns with anorectal
malformations. U/S, ultrasonography; R/O, rule out.
Cross tablelateral view
ColostomyDrain hydrocolpos
Urinary diversion(if necessary)
Colostomy
or primary repair
Rectumbelowcoccyx
Colostomy
No viziblefistula (
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NEWBORNMANAGEMENT(FEMALE)
Again, the perineal inspection is the most important step to guide diagnosis
and decision making.
The first 24 hours should also be used to evaluate for serious associated
defects, as previously described.
The perineal inspection may disclose the presence of a single perineal
orifice.
This single finding establishes the diagnosis of a cloaca, which carries a
high risk of an associated urologic defect.
The patient needs a complete urologic evaluation, including abdominal and
pelvic ultrasonography, to look for hydronephrosis and hydrocolpos.
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NEWBORNMANAGEMENT(FEMALE)
Patients with a cloaca require a colostomy.
It is important to perform the divided sigmoid colostomy in such a manneras to leave enough redundant, distal rectosigmoid colon to allow for the
subsequent pull-through (Fig. 28)
Figure 28. An ideal colostomy for infants with high anorectal malformations is seen in thedrawing (A) and infant (B). Note the colostomy (1) and mucous fistula (2) are separated and
that adequate distal colonic length remains for the subsequent rectal pull-through.
A B
1
2
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NEWBORNMANAGEMENT(FEMALE)
When performing the colostomy, it is mandatory to drain the hydrocolpos
when present. Because a significant number of these patients have two hemivaginas, the
surgeon must be certain that both hemivaginas are drained.
It is the hydrocolpos that compresses the trigone and causes bilateral
hydronephrosis, and drainage of the hydrocolpos allows for decompression
of the urologic system.
Rarely, if the common channel is very narrow and does not allow the bladder
to drain, the neonate may require a vesicostomy or suprapubic cystostomy to
decompress the bladder.
Endoscopic examination of the cloaca is recommended to delineate the
anatomy.
This is best done later (in several months) during a separate anesthetic
because the neonatal perineum is swollen and endoscopy is difficult.
( )
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NEWBORNMANAGEMENT(FEMALE)
The presence of a vestibular fistula represents the most common finding in
female patients (see Fig. 8).
When newborns with a vestibular fistula undergo primary repair, the patient
should be kept for 5 to 7 days without any oral intake, on parenteral
nutrition. Conversely, when the patient undergoes a primary repair of a vestibular
fistula or perineal fistula without colostomy later in life, preoperative bowel
irrigation for 24 hours preoperatively will ensure that the intestine is
completely clean.
Then the patient is kept on parenteral nutrition 7 to 10 days with nothing bymouth, all in an attempt to avoid a perineal infection.
N ( )
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NEWBORNMANAGEMENT(FEMALE)
The perineal inspection may show the presence of a perineal fistula. When
present, we recommend performing a primary anoplasty without acolostomy.
In fewer than 5% of girls, there is no visible fistula and there is no evidence of
meconium after 24 hours of observation.
This small group of patients requires a cross-table lateral prone radiograph
(see Fig. 24).
If the radiograph shows gas in the rectum very close to the skin, it means that
the patient very likely has a very narrow perineal fistula. Conversely, if the
distal extent of the rectal gas is located 1 to 2 cm above the skin, the patient
most likely has an imperforate anus with no fistula.
If the patient is in stable condition, one can perform a primary operation
without a colostomy, depending on the surgeonsexperience.
Most of these patients with no fistula also have Down syndrome. In the event
that associated conditions make the rectal repair unfeasible in the newborn
period, a colostomy should be performed, with definitive repair later.
N ( )
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NEWBORNMANAGEMENT(FEMALE)
Occasionally, if the infant with a rectoperineal or rectovestibular fistula has
severe associated defects or is ill, the surgeon may elect to dilate the fistula
to facilitate emptying of the colon while these other issues are addressed.
Definitive repair can be performed in a few months.
A divided descending colostomy is ideal for the management of anorectalmalformations (see Fig. 28).
The completely diverting colostomy provides bowel decompression as well as
protection for the final reconstruction of the malformation.
In addition, the colostomy is used for the distal colostogram, which is the
most accurate diagnostic study to determine the detailed anatomy of thesedefects.
NEWBORN MANAGEMENT
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NEWBORN MANAGEMENT
The descending or upper sigmoid colostomy has definitive advantages over aright or transverse colostomy.
It is important to have a relatively short segment of defunctionalized distalcolon, but not too short as to interfere with the subsequent pull-through (Fig.29) .
Figure 29. A, It is important not to create the colostomy too distal because there will not besufficient rectal length to allow for pull-through. B, This problem is seen on the lateral view of
the barium enema, where there is insufficient distal rectal length for the pullthrough. This is
because of an inappropriately placed colostomy and mucous fistula.
A B
SURGICAL TREATMENT
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SURGICALTREATMENT
(GENERALITIES)
Historically, there have been many surgical techniques to repair anorectal
malformations.
These include endorectal dissection, anterior perineal approaches, and
many different types of anoplasties.
Most pediatric surgeons now use the posterior sagittal approach with orwithout laparotomy or laparoscopy to repair these malformations.
The debate recently has been centered more on the possibility of performing
these operations primarily without a colostomy, or for which cases a
laparoscopic approach is best suited.
POSTERIOR SAGITTAL APPROACH
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POSTERIOR SAGITTAL APPROACH
The patient is placed in the prone
position with the pelvis elevated.
An electrical stimulator is used
to elicit muscle contraction
during the operation. The
demonstrated contraction serves
as a guide to keep the incision in
the midline, leaving an equal
amount of muscle on both sides.
The length of the incision varies
with the type of defect and can
be extended to achieve the
necessary exposure needed to
have a satisfactory repair.
POSTERIOR SAGITTAL APPROACH
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POSTERIOR SAGITTAL APPROACH
Thus, a perineal fistula requires a
minimal posterior sagittalincision (2 cm), whereas higherdefects may require a full
posterior sagittal incision thatruns from the lower portion ofthe sacrum toward the base ofthe scrotum in the male or to thesingle perineal orifice in femaleswith a cloaca.
The incision includes the skinand subcutaneous tissue andsplits the parasagittal fibers,muscle complex, and levator
muscles in the midline. In simpledefects (perineal and vestibular),the incision divides only the
parasagittal fibers and the musclecomplex in the midline.
POSTERIOR SAGITTAL APPROACH
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POSTERIOR SAGITTAL APPROACH
It is not usually necessary to open the levator muscle.
Once the sphincter mechanism has been divided, the next most important
step of the operation is the separation of the rectum from the urogenital
structures, which represents the most delicate part of the procedure.
Any kind of blind maneuver at this point in the operation exposes the
patient to the possibility of serious injury. About 90% of defects in boys can be repaired via a posterior sagittal
approach without opening the abdomen and without laparoscopy.
Each case has individual anatomic variants that mandate technical
modifications.
An example is the size discrepancy frequently seen between an ectaticrectum and the space available for the pull-through.
If the discrepancy is significant, the surgeon must tailor the rectum to fit.
POSTERIOR SAGITTAL APPROACH
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POSTERIOR SAGITTAL APPROACH
If a colostomy has been done, the posterior sagittal approach should never be
attempted without a technically adequate high-pressure distal colostogram todetermine the exact position of the rectum and the fistula (Fig. 30, 31).
Figure 30. Distal colostogram, posteroanteriorview. The initial phase of augmented-pressuredistal colostography aims to determine wherethe colostomy was placed in the colon and how
much colon is available for pull-through,without taking down the colostomy.
Figure 31. Distal colostogram, lateralview. image shows that the rectal pouchjoins the urinary tract at the level of thebulbar urethra, a relatively common
malformation in boys.
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MALE DEFECTS
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REPAIR OF RECTOPERINEAL FISTULA
The operation in these infants is performed in
the prone position with the pelvis elevated.Multiple 6-0 silk stitches are placed in thefistula orifice.
An incision is created dividing the sphinctermechanism located just posterior to thefistula. The sphincter is divided, and theposterior rectal wall is identified by its
characteristic whitish appearance. Dissection of the rectum continues laterally
following this specific plane. The last part ofthe dissection consists of separating theanterior rectal wall from its intimate relationto the urethra.
The patient must have a urinary catheter
inserted preoperatively.
The best way to avoid urethral injury is tocontinuously be aware of the fact that thecommon wall has no plane of dissection andthat the surgeon must create two walls out ofone. Fig.32. Rectoperineal fistula in a male
newborn
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Fig. 33. Rectourethral bulbar fistula Fig. 34. Rectourethral prostatic fistula
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o We like to perform a cystoscopy in all patients,which helps the surgeon confirm the location of the fistula.
o A Foley catheter is inserted and the patient is placed in prone position with the pelvis elevated.
o The incision is a posterior sagittal one, in between both buttocks, running from the middle portion of thesacrum down to the anal dimple, which is electrically determined. The incision goes through skin,subcutaneous tissue, parasagittal fibres,muscle complex and levator muscle (Fig. 35 a, b, c).
o When the surgeon is dealing with a rectourethral bulbar fistula (Fig. 33), he expects to see a bulging rectumas soon as he opens the levator muscle. In cases of the rectoprostatic fistula, (Fig. 34) the rectum is muchsmaller, it may not bulge through the incision, and the surgeon expects to find the rectum immediately belowthe coccyx.
o The surgeon should not look for the rectum in the lower part of the incision in patients with rectoprosaticfistula. Looking for a rectum without evidence that the rectum is there is the main source of complications inthis approach. The surgeon will find the urethra, vas deferens, prostate, and seminal vesicles and willdamage the nerves important for urinary control and sexual potency.
Fig. 35. Posterior sagittal approach.
a b c
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The posterior rectal wall is easilyidentified by its characteristic whitishappearance (Fig. 36 a, b).
The surgeon must keep in mind that thereis a fascia that covers the rectumposterior and laterally that must beremoved.
The dissection of the rectum must be
performed staying as close as possible tothe rectal wall without injuring the rectalwall itself.
The posterior rectal wall is opened in themidline, in between two 5/0 silk stitches.
The incision is continued distally, stayingin the midline while applying stitches in
the edges of the rectum. The traction on these stitches will allow
the surgeon to see the lumen of therectum.
When the incision continues, extendingdistally in the midline, it ends directlyinto the rectourethral fistula that isidentified usually as a 12 mm orifice.
Fig. 36. Posterior sagittal approach.
a b
REPAIR OF RECTOURETHRAL FISTULAS
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Multiple 6/0 silk sutures are placed in asemi-circumferential fashion
surrounding the fistula site above and
lateral to the fistula (Fig. 37).
These multiple sutures serve the
purpose of exerting uniform traction onthe rectal mucosa to facilitate the
separation of the rectum from the
urinary tract.
The fascia that covers the rectum is
removed, creating the lateral planes ofthe rectum.
The mucosa of the anterior rectal wall
distal to the multiple 6/0 silk sutures is
divided about 1 mm deep.
Fig. 37. Posterior sagittal approach. Applying silksutures in a semi-circumferential fashionsurrounding the fistula site above and lateral
to the fistula
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The dissection continuesbetween the rectum and urinarytract in a submucosal plane forapproximately 510 mm andthen gradually becomes a full-thickness dissection, looking atthe lateral planes until therectum is completely separatedfrom the urinary tract.
The separation of the urethrafrom the rectum is the mostdelicate part of the operation.
Most of the seriouscomplications occur during this
part of the procedure. The fistula site is closed with
three or four 6/0 long-termabsorbable sutures (Fig. 38 a,b). Fig. 38. Posterior sagittal approach. Surgical
dissection between the rectum and urinary tractand closing the fistula.
a b
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The surgeon should then evaluate the size of
the rectum and compare it to the availablespace to decide if the rectum has to betapered to be accommodated within thelimits of the sphincters (Fig. 39).
In the past, we performed many of thesetapering procedures and we believe that isbecause patients came later in life, hadinadequate colostomies, and therefore
suffered from severe megarectum. Currently, babies are referred to us earlier,
surgeons are opening better, totally divertingcolostomies, and we therefore do not seemegarectums as often.
Consequently, tapering is rarely necessary.
When a tapering procedure is required, we
recommend to remove an adequate portion ofthe posterior rectal wall, closing this wallinto two layers of interrupted long-termabsorbable sutures.
Tapering on the anterior wall is absolutelycontraindicated as it would leave a rectalsuture line against the urethral fistula repairand a recurrent fistula may develop.
Fig. 39. Posterior sagittal approach. Tapering ofthe rectum.
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The limits of the sphincter are then
electrically determined and marked
with temporary silk sutures.
The perineal body is reconstructed
when the incision extends anterior tothe centre of the sphincter.
The anterior limits of the sphincter
must be reconstructed (Fig. 40).
Fig. 40. Posterior sagittal approach. Marking thesphincter and reconstruction of the perinealbody and anterior limits of the sphincter.
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The posterior edge of the levator muscle
is electrically determined, and therectum is placed in front of the levator.
The posterior edges of the levatormuscle are sutured together withinterrupted 5/0 long-term absorbablesutures.
The distal continuation of the levatormuscle is arbitrarily called the musclecomplex.
The posterior edge of this musclestructure is sutured together in themidline with interrupted 5/0 long-termabsorbable sutures.
These sutures also take a bite of theposterior rectal wall in order to anchorthe rectum in a good position to avoidretraction and/or prolapse (Fig.41).
Fig. 41. Posterior sagittal approach.
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The rest of the incision is closedmeticulously reapproximating
all the layers of the wound.
An anoplasty is performed with
16 circumferential stitches of
6/0 long-term absorbablesutures, trimming off that part of
the rectum that has been
damaged or does not have
adequate blood supply. (Fig. 42
a, b).
Fig. 42. Posterior sagittal approach. Closing thewound and anoplasty.
a b
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This malformation is the highest of all
defects seen in male patients (Fig.43).Fortunately, only 10% of male patients suffer
from this particular defect. Associated
defects occur in 90% of these patients.
Usually, the sacrum is hypodeveloped.
This particular group of malformations is the
only one that, in order to be repaired,requires not only a posterior sagittal
approach, but also an abdominal one, either
by laparotomy or laparoscopy.
During the laparotomy or laparoscopy, the
surgeon must separate the rectum from the
urinary tract. Fortunately, in these very high
malformations, the common wall between
the rectum and the urinary tract is very short.
In other words, the rectum connects to the
bladder neck in a Tfashion.
Fig. 43. Recto-bladder neck fistula.
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Total body preparationshould be performed.
The operation is started via a posterior sagittal approach. All the sphincter mechanisms are
divided in the midline.
No attempt should be made to find the rectum through this approach.
A rubber tube is placed in the presacral space behind the urethra and located, following the tract
the rectum will subsequently occupy.
The perineal body, the posterior edge of the levator muscle as well as the muscle complex are
reconstructed around the rubber tube that represent the rectum (Fig. 44 a, b).
Fig. 44.Recto-bladder neck fistula repairing.
a b
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The patient is then turned onto a supine position and a laparotomy is performed.
The bladder is pulled anteriorly and the rectosigmoid is found.
In these very high defects, the rectobladderneck fistula is usually located within 1 to 2 cm below
the peritoneal reflection and, therefore, the pelvic dissection necessary to mobilize it is minimal
(Fig. 44 a, b).
Fig. 44.Recto-bladder neck fistula repairing.
a b
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Ureters and vas deferens run very close to the rectum to approach the trigone of the bladder.This should be kept in mind to avoid any damage.
The dissection of the rectosigmoid must be performed while staying in direct contact with thebowel wall itself. The rectum opens into the bladderneck in a T fashion.
This means that there is no common wall above the fistula as described in lower malformations.The fistula is divided and the bladder end is sutured with interrupted long-term absorbablesutures. The rubber tube is easily found in the presacral space.
The decision is made to taper the rectum when necessary and then to anchor the rectum to therubber tube. The legs are lifted up and the rubber tube is pulled down, pulling together therectum that will be placed in the desired location. The anoplasty is performed as previously
described and the abdomen is closed (Fig. 44 a, b).
Fig. 44.Recto-bladder neck fistula repairing.
a b
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FISTULA
This particular malformation is unique. When we say imperforated anus without
fistula, we do not have to refer to theheight of the defect because in all casesthe rectum is located approximately 12cm above the perineal skin, at the level ofbulbar urethra.
This malformation only happens in 5% ofall cases and half of these have Downssyndrome.
The patients with these defects have goodprognosis, good sacrum and goodsphincters.
Ninety percent of our patients with thisdefect without Downs syndrome havebowel control and 80% of our Downssyndrome patients have bowel control.
Fig.45. Imperforate anus repairing.
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FISTULA
The technique to repair this malformation
is not necessarily simpler than the one for
rectourethral bulbar fistula since the
rectum is intimately attached to the
posterior urethra.
The surgeon has to open the posteriorrectal wall and still has to create a plane
of dissection between the anterior rectal
wall and the urethra, a manoeuvre that
requires a meticulous dissection (Fig.45).
Fig.45. Imperforate anus repairing.
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FEMALE DEFECTS
FEMALE DEFECTS
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Female defects are represented by a similar spectrum.
However, over the last 22 years, we have been learning a great deal about these defects,
particularly with regard to cloacas.
We have learned, for instance, that the so-called rectovaginal fistula is an almost nonexistent
defect.
Most of the patients that were referred to us after having an operation to repair a rectovaginal
fistula,actually never suffered from that particular defect.
Most of them suffered originally from a cloaca that was misdiagnosed; the surgeon repaired
the rectal component of the defect and left the patient with a persistent urogenital sinus.
In other more unfortunate cases, the babies were born with rectovestibular fistulas, the
surgeons mislabelled and misdiagnosed it as a rectovaginal fistula and performed an
abdominal perineal procedure for a malformation that could otherwise have been repaired
posterior sagittally with good results, leaving the patient totally incontinent for faeces.
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This defect is equivalent to the recto-perineal
fistula in males already described. Bowel control exists in 100% of our patients and
less than 10% of them have associated defects.
The patients are faecally continent with and
without an operation.
Constipation is a constant sequela and should be
treated energetically. This is true also for the malepatients with perineal fistulas. We have learned
that the lower the defect the more there is a
chance of constipation.
We have also learned that constipation is a self-
perpetuating and self-aggravating condition that
eventually produces severe megacolon, chronicfaecal impaction and overflow pseudo-
incontinence, and must vigilantly be avoided
(Fig.46).Fig.46. Rectoperineal fistula in a femalenewborn
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In our opinion the better way to repair this defect
is to perform the operation at birth. The mainreasons are to avoid cosmetic, psychological and
potential obstetric sequelae in the future. We
perform this operation before the baby leaves the
hospital during the newborn period.
The patient is placed in prone position with the
pelvis elevated. Multiple 6/0 silk stitches areplaced around the fistula site. The incision is
about 1.52 cm long and divides the entire
sphincter mechanism in the posterior midline. We
dissect the rectum as previously described in the
case of perineal fistulas in male patients. The
perineal body is reconstructed as shown and the
rectum is anchored to the posterior edge of themuscle complex. An anoplasty is performed.
These patients can eat on the same day of the
surgery, and since they are only passing non-
colonized meconium, we give antibiotics for 48
h.
Fig.46. Rectoperineal fistula in a femalenewborn
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This defect is perhaps the most important
anorectal malformation in females.
This is because it is by far the most common
defect seen in the females. It is also a
malformation that has an excellent functional
prognosis when managed correctly.
Also, paradoxically and unfortunately, girls with
these defects are the ones that we have seen suffer
from more complications after a failed attempt to
repair.
For many years, it has been very controversial
whether this malformation should be treated witha previous protective colostomy or should be
operated primarily at birth.Fig.47. Rectovestibular fistula in a femalenewborn
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Again, we believe that this depends very much on
the experience of the surgeon.
When a baby is born with this malformation at
our institution and the baby is otherwise healthy,
we repair this malformation during the newborn
period.
If the baby is premature or has associated defects,
it is always safer to open a protective colostomy.
The surgeon must keep in mind that dehiscence
and infection in patients with anorectal
malformations not only represent a few more
days in the hospital and an ugly scar but also
represents the possibility of changing theprognosis for bowel control.
Fig.47. Rectovestibular fistula in a femalenewborn
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Bowel control exists in 93% of our patients; 70%
of them have constipation that is incurable but
manageable and it should be treated aggressively.
The most important anatomical feature that
should be recognized by the surgeon is that the
rectum and vagina share a long common wall that
must be separated, creating a plane of dissectionwhere it does not exist, in order to mobilize the
rectum and put it in the right place.
We believe that most of the complications that we
have seen from treatment of this malformation
originate from the lack of separation of these twostructures, or the defective separation of these
two structures. Fig.47. Rectovestibular fistula in a femalenewborn
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These patients are also placed in prone position with the pelvis elevated.
The incision runs usually from the coccyx down to the fistula site.
Again, multiple 6/0 sutures are placed in a circumferential manner in the fistula opening. Traction always facilitates the dissections of these delicate structures.
The entire sphincter mechanism is divided posteriorly until we identify the posterior rectalwall, and then the plane of dissection is established removing the fascia that covers the rectum.
The dissection then continues laterally.
Fig.48.Rectovestibular fistula repairng in a female newborn
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The surgeon must put a special emphasis on a very meticulous separation of the rectum fromthe vagina.
The purpose of this dissection is to make two walls out of one.
He or she should try at all costs to avoid making perforations in the rectal wall or the vaginalwall.
Once the rectum has been completely separated from the vagina, the surgeon determines thelimits of the sphincter electrically and reconstructs the perineal body, bringing together theanterior limits of the sphincter.
Fig.48.Rectovestibular fistula repairng in a female newborn
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The rectum is then placed within the limits of the sphincter as well as the muscle complex.
We can see only the lower part of the levator because the incision is rather limited in thisoperation.
The rectum is anchored to the posterior edge of the muscle complex and the anoplasty isperformed like we discussed in the previous cases.
When the patient is a newborn, we keep the baby 2 or 3 days with nothing by mouth post-operatively, while receiving intravenous antibiotics.
Fig.48.Rectovestibular fistula repairng in a female newborn
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Technical variant called total urogenital mobilization (Fig. 49):
The rectum is separated from the vagina in the same way that they were separated in the casesof rectovestibular fistula.
Once we expose the malformation, multiple 6/0 silk stitches are placed taking the edges of thecommon channel and the edges of the vaginal walls.
We use those stitches to exert a uniform traction.
Then urethra and vagina together are mobilized in what we call total urogenital mobilization.
Another set of sutures is placed in a transverse fashion taking the mucosa of the commonchannel 5 mm proximal to the clitoris and then the entire common channel is divided, full
thickness, creating a plane of dissection between the pubis and the common channel.
Fig.49. Total urogenital mobilization.
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This is a natural plane of dissection and therefore it is very easy to dissect.
We reach the upper part of the pubis and there we can identify avascular fibrous structures thatfix the genitourinary structures to the pelvis.
These are divided and that allows an immediate gain of length of the urogenital structures ofapproximately 24 cm,which is enough to repair the malformations with short commonchannels.
The goal of this mobilization is to move what used to be a urethral meatus all the way down, tobe placed immediately behind the clitoris to be visible and accessible for future urethralcatheterizations when indicated.
The vagina comes down together with the urethra and the edges of the vagina are sutured to the
skin of the perineum forming the new labia.
Fig.49. Total urogenital mobilization.
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What used to be the common channel is divided in the midline creating two flaps that arepreserved and sutured to the new labia to enrich that tissue.
All this reconstruction is performed with interrupted 6/0 long term, absorbable sutures.
With these kinds of techniques, in patients with a good sacrum, 80% of them have bowelcontrol and approximately 80% of them can empty the bladder voluntarily without intermittentcatheterization, and remain dry of urine; 20% of them require intermittent catheterization toempty the bladder.
Fortunately, they have a good bladder neck and they remain dry between catheterizations.
When the sacrum is very abnormal, the results are not as good.
Fig.49. Total urogenital mobilization.
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The repair of patients suffering from cloacas with longer common channels (>3 cm) representsa real technical challenge and requires a great deal of experience in the management of thesecases.
For that kind of patient, the surgeon should have experience in the management of the urinarystructures including bladder reconstructions, bladderneck reconstructions, ureteralreimplantations, bladder augmentation and Mitrofanoff procedures.
In cases with long common channels, if the pediatric surgeon and/or pediatric urologist bothhave experience with these malformations they continue with the repair, performing first whatwe call a total body preparation in order to have access both to the perineum and the abdomen.
Fig.49. Total urogenital mobilization.
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If the common channel is longer than 5 cm, we recommend opening the abdomen directly inthe midline because, in that particular case, rectum and vaginas are not accessible posteriorsagittally and are more easily accessed through the abdomen.
If the common channel is between 3 and 5 cm, the surgeon can open posterior sagittally, stillwill find the vagina or vaginas and can try to repair them by performing the total urogenitalmobilization.
If the total urogenital mobilization proves not be enough to repair the malformation then theoperation must be completed through a laparotomy.
Fig.49. Total urogenital mobilization.
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The separation of the rectum from the vagina is not difficult in very high malformations since itis similar to what we described in the separation of the rectum from the bladder neck in malepatients.
On the other hand, the separation of the vagina from the urinary tract in a case of a cloaca with along common channel is a very delicate manoeuvre that requires expertise and finesse.
Once the vagina has been completely separated, which is a manoeuvre that may take severalhours, the surgeon then has to make important decisions considering the way to repair thevagina.
The separation of the vagina from the urinary tract should be performed with the bladder open inthe midline and with ureteral catheters.
Fig.49. Total urogenital mobilization.
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The ureters run through the common wall that separates the vagina from the bladder andtherefore, the surgeon should be ready to deal with the fact that the ureters may be right in theplane of separation.
Once the vagina has been separated, the surgeon should evaluate the size of the mobilizedvaginas and the length that he needs to bring the vagina down.
It may be that the patient has a very large vagina that reaches the perineum.
Fig.49. Total urogenital mobilization.
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Clinical results are different for each type of the malformations.
A recent review of the authors series showed that 100% of patients with rectal atresia and
perineal fistula had voluntary bowel movements, those with vestibular fistula 93.8%, bulbarurethral fistula 87.5%, imperforate anus without fistula 85%, cloaca 83.3%, rectourethral
prostatic fistula 76.5%, and bladderneck fistula 28.6%.
Soiling in patients who enjoy voluntary bowel movements usually represents a manifestation of
faecal impaction and when the constipation is treated properly, the soiling usually disappears.
Patients who enjoy voluntary bowel movements and never soil are considered totallycontinent.
Constipation is a common sequela seen after the repair of an anorectal malformation.
Interestingly, patients with lower defects, and therefore with better prognosis for bowel control,
suffer a higher incidence of constipation and vice versa.
Constipation correlates directly with the degree of rectosigmoid dilation at the time of
colostomy closure.
Therefore, every effort should be made to try to keep the rectosigmoid empty and
decompressed from day 1 in these patients.
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Urinary control can be expected in the overwhelming majority of male patients after repair of
imperforate anus provided a good surgical technique was performed.
Urinary incontinence is a concern only in male patients with absent sacrum or in some femalepatients with cloaca.
In this last defect, when the common channel is shorter than 3 cm, approximately 20% of
patients require intermittent catheterization to empty the bladder.
The remaining 80% enjoy urinary control.
When the common channel is longer than 3 cm it was observed that 68% of the patients requireintermittent catheterization to empty the bladder.
Fortunately, after the repair of a cloaca, patients have a good bladderneck; they have the
capacity to empty the bladder.
Thus, when the bladder becomes completely full, the patients start suffering from overflow
urinary incontinence.
Intermittent catheterization keeps these patients completely dry.
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25. Levitt MA, Stein DM, Pena A. Gynecologic concerns in the treatment of teenagers with cloaca.J Pediatr Surg. Feb 1998;33(2):188-93. [Medline].
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