15.5Investigations

•Plain radiography of the spine:

–This is to look for spinal anomalies, such as spina bifida and spinal hemivertebrae.

•Plain radiography of the sacrum:

–This is to look for sacral anomalies, such as a hemisacrum and sacral hemivertebrae.

–The degree of sacral hypodevelopment can also be assessed.

–Traditionally, to evaluate the degree of sacral hypodevelopment, the number of sacral vertebral bodies was counted.

–A more objective assessment of the sacrum can be obtained by calculating the sacral ratio.

–To calculate the sacral ratio (Fig. 15.8):

•The distance from the coccyx to the sacroiliac joint is measured and divided by the distance from the sacroiliac joint to the top of the pelvis.

•To calculate the sacral ratio, a lateral radiography is more accurate than the anteroposterior view.

•The sacral ratio is important as this correlates with the patient’s functional prognosis.

•The normal sacral ratio is greater than 0.7.

•Bowel control has rarely been observed in patients with ratios less than 0.3.

–A hemisacrum is almost always associated with a presacral mass, commonly a teratoma, or an anterior meningoceles.

NORMAL RATIO = BC ÷ AB = 0.74

Fig. 15.8 Diagrammatic representation of calculating the

–The Currarino triad, which includes an anorectal malformation, a hemisacrum, and a presacral mass should be excluded.

•Abdominal ultrasonography is useful to evaluate intraabdominal organs including the vagina and uterus as well as the presence or absence of hydrocolpos.

•Spinal ultrasonography is also used in infants less than 3 month to evaluate for tethered cord.

•Echocardiography to detect associated cardiac anomalies.

•A distal loopogram in those with a preliminary colostomy. The position of the rectum must be carefully checked to determine whether it can be comfortably reached from a posterior sagittal incision (Fig. 15.9).

•Prior to definitive repair of cloacal malformations, it is important to determine the length of the common channel and the length of the urethra from the common channel to the bladder neck.

•This is determined using cystoscopy with vaginoscopy and a three-dimensional (3D) cloacagram under anesthesia. This is also valuable in studying the genital anatomy (vaginal septum, numbers and patency of cervices, and size and height of the vagina) (Fig. 15.10).

•A cloacagram is performed by injecting a water soluble contrast into the single perineal orifice and taking radiographs that will show the bladder, vagina and rectum and their anatomic relation. Cross-lateral radiographs are more informative as well as the length of the common channel.

•MRI is currently the procedure of choice to evaluate the anomalies of the cloaca, the presence of tethered cord, sacrum and spine. MRI

is used in infants older than 3 months (Fig. 15.11).

•Cystoscopy and vaginoscopy are essential components for evaluation of the patient with persistent cloaca. These are usually performed before the main repair to define the anatomy and plan the surgical repair. The following anatomic points are checked:

–The length of the common channel

–The presence of a vagina

–The presence of hemivagina

Fig. 15.10 A contrast study through the perineal opening showing the vagina, the urethral opening and rectum

–The presence of a cervix (or cervices)

–The visualization of the rectal fistula

15.6Management (Figs. 15.12, 15.13, 15.14, 15.15, and 15.16)

•The goals of early management of cloaca are:

–To detect associated anomalies.

–To achieve satisfactory diversion of the gastrointestinal tract.

–To drain associated hydrocolpos

–To divert the urinary tract when necessary

–To achieve bowel control, urinary control, and normal sexual function.

•Total diversion of the fecal stream is made with an end colostomy placed in the descending colon and with a mucous fistula.

•This total diversion of the fecal stream is important to prevent urinary infections.

•It is important to leave an adequate bowel length distal to the site of the colostomy for subsequent pull-through.

•The definitive procedure to repair cloaca is posterior sagittal anorectovaginourethroplasty.

•This procedure simultaneously repairs the rectal, vaginal, and urethral anomalies.

•The more complex anomalies are repaired using a combined abdominal approach and posterior sagittal anorectovaginourethroplasty.

•The repair of persistent cloaca represents a technical challenge and should be performed in specialized centers by pediatric surgeons dedicated to the care of these patients.

•The management of cloaca is performed in stages.

–The first stage is in the newborn period and consists of fecal diversion and urinary and vaginal diversion if necessary.

–The definitive repair of cloaca is performed at a later date. This is done using the posterior sagittal anorectovaginourethroplasty (PSARVUP). Complex cases will require laparotomy also. This depends on the

UTERUS

FALLOPIAN

TUBE

VAGINA

URINARY

BLADDER

Fig. 15.12 An intraoperative photograph of a patient with cloaca who presented with hydrometrocolpos. Note the distended vagina and uterus

length of the common channel which varies from 1 to 10 cm.

–This is followed by colostomy closure.

•The goals of surgical treatment are to achieve bowel control, urinary control, and normal sexual function. This depends on:

–The quality of the sacrum and spine

–The quality of the sphincter muscles

–The length of the common channel

•If the common channel is shorter than 3 cm, the posterior sagittal approach can be used to repair the defect without an abdominal approach.

–The rectum is mobilized first and the vagina and urethra are then mobilized together (total urogenital mobilization).

–Total urogenital mobilization allows mobilization of the urethra and vagina as one structure.

•For patients with a common channel longer than 3 cm, a laparotomy is usually required.

–The vagina and urinary tract are separated to gain length

–The urethra is then reconstructed.

–Complex vaginal mobilizations are often required, and vaginal replacement (with colon or small intestine) is frequently necessary

•Posterior sagittal anorectovaginourethroplasty (PSARVUP) consists mainly of:

–Separating the rectum from the urogenital tract.

–Followed by separation of the vagina from the urethra and bladder.

–Reconstruction of the common channel as a neo-urethra.

–Mobilization and dissection of the vagina so that it could be pulled down to be placed posterior to the urethra wall.

–Performance of a pull-through of the rectum. The pull-through rectum is placed within the limits of the sphincter mechanism, which is determined with an electrical stimulator.

•The repair can usually be performed using only the posterior sagittal approach.

•For more complex anomalies, an abdominal approach is added to mobilize a very high vagina or gain length on a very high rectum.

•If the common channel is shorter than 3 cm, the posterior sagittal approach can be used to

repair the defect without an abdominal approach.

•For patients with a common channel longer than 3 cm, a laparotomy is usually required.

•Complex vaginal mobilizations are often required, and vaginal replacement (with colon or small intestine) is frequently necessary.

•Total urogenital mobilization is a technique that allows mobilization of the urethra and vagina as one structure.

•If total urogenital mobilization does not adequately lengthen the vagina, the vagina and urethra must be separated, which is a technically challenging procedure.

•The pulled-through rectum is placed within the limits of the sphincter mechanism, which is determined with an electrical stimulator.

•Total diversion of the gastrointestinal tract is achieved with a colostomy (a double barrel colostomy) placed in the descending colon. This leaves a sufficient length of the colon for subsequent pullthrough.

•Total diversion of the fecal stream is necessary to avoid spillage and prevent urinary tract infections.

•The patient must be left with a good length of distal colon long, enough for the future pullthrough, and sometimes for a vaginal replacement if needed.

•The mucous fistula is also important for radiologic evaluation of the distal colon.

•A Foley catheter is placed in the bladder and this remains in place for approximately 10–14 days. For more complex cases, a vesicostomy or suprapubic cystostomy tube may be needed for longer-term urinary diversion.

•Anal calibration is performed 2 weeks after the operation, followed by a program of anal dilatations.

•Once the desired size is reached, the colostomy can be closed.

•Cystoscopy and vaginoscopy should be performed before colostomy closure to ensure that no urethrovaginal fistula is present.

•A urethrovaginal fistula if present will need to be closed prior to colostomy closure.

•Patients with cloaca have no contraindications to definitive surgery when future fecal or urinary incontinence is a concern.

•Even for patients with incontinence, a bowel management program is almost always successful in keeping a patient clean and dry.

•In patients in whom bowel management is unsuccessful (<3 %), a permanent colostomy may be the best option to ensure good quality of life.

•In patients with urinary incontinence, many options are available for keeping a patient clean.

•Urinary diversions, such as the Mitrofanoff procedure and the use of intermittent catheterization, are usually successful in keeping the patient dry of urine.

•The repair of persistent cloaca represents a technical challenge and should be performed in specialized centers by pediatric surgeons dedicated to the care of these patients. This especially for cloaca with a long common channel.

•A distal colostogrphy through the mucous fistula is essential to outline the anatomy.

•Cystoscopy and vaginoscopy are essential components for better evaluation of the patient with persistent cloaca. This is important to define the anatomy and plan surgical reconstruction. It is important to determine the

length of the common channel, the presence of vagina or a bifid vagina, the presence of one cervix or more and the site of rectal fistula. This is valuable and help the surgeon to predict whether a laparotomy will be required in combination with the posterior sagittal approach.

•Prognostic factors include:

–The quality of the sacrum and spine.

–The quality of the sphincter muscles.

–The length of the common channel.

•Approximately 50 % of patients have various degrees of vaginal or uterine septation. These can be totally or partially repaired during the main operation.

•The Foley catheter remains in place for approximately 10–14 days.

•Anal calibration is performed 2 weeks after the operation, followed by a program of anal dilatations. Once the desired size is reached, the colostomy can be closed.

•Cystoscopy and vaginoscopy should be performed before colostomy closure to ensure that no urethrovaginal fistula is present, which would necessitate a reoperation which should be done with the colostomy still in place.

•Dilatations are continued afterward according to a prescribed protocol. They are a vital part of the postoperative management to avoid a stricture at the anoplasty site.

•Many of these patients require a bowel management program to keep them clean and dry.

•In patients in whom bowel management is unsuccessful (<3 %), a colostomy may be the best option to ensure good quality of life.

•In patients with urinary incontinence, many options are available for keeping a patient clean.

•Urinary diversions, such as the Mitrofanoff procedure and the use of intermittent catheterization, are usually successful in keeping the patient dry of urine.

•Many of these patients require prophylactic antibiotics for urinary tract infections for associated vesicoureteral reflux.

•Intermittent catheterization is required in 70 % of patients with persistent cloaca who have a common channel longer than 3 cm, compared