1. GASTROGRAFFIN EVALUATION OF ANORECTAL ANOMALIES: A CASE REPORT
Author: Dr. Swarnava Tarafdar
Senior Resident, Department of Radiodiagnosis, A.I.I.M.S. Jodhpur

2. Background
Anorectal malformations are congenital anomalies that occur in approximately 1 in 5000 live births.
20 to 70 % patients has associated congenital anomalies
They have male predominance.
Spine, genitourinary, gastrointestinal and cardiac system frequently affected.
Associated genitourinary anomalies found in upto 26 % patients of anorectal malformation
Skeletal anomalies such as sacral bony abnormalities found in upto 21% patients.

3. Background
High anomaly: Gas bubble above the pubococcygeal line Intermediate anomaly: Gas between pubococcygeal line and Ischial line Low anomaly: Gas below ischial line
PC - Pubococcygeal line
I - Ischial line

4. International classification Anorectal agenesis High anomaly:
MALES
FEMALES
Anorectal
agenesis
Rectal
atresia
Anorectal
agenesis
Rectal
atresia
Without fistula
With fistula
Without fistula
With fistula
Rectovesical Rectoprostatic urethral-most common type (including H or N type)
Rectovesical
Clocal anomalies
Rectovaginal (High)

5. High Anorectal anomalies in males
Rectoprostatic urethral fistula
Rectovesica fistula
H or N Type rectoprostatic urethral fistula
Rectal atresia

6. High ARA in Females
Rectovaginal fistula

7. Intermediate anomaly MALES FEMALES Anal agenesis Anorectal Stenosis
Without fistula
With fistula
Without fistula
With fistula
Rectobulbar
Rectovaginal (low)
Rectovestibular

8. Intermediate anomaly Males: Anal agenesis with
Rectobulbar urethral fistula
Females: Rectovestibular fistula

9. Low anomalies MALES FEMALES At normal anal site At perineal site
At vulvar
site
Anterior
perineal anus
Covered anus,
complete
Anterior
perineal anus
Covered anus,
complete
Anovulvar anus
Anal
stenosis
Anocutaneous
fistula
Anovestibular
fistula
Anal
stenosis
Anocutaneous
fistula
Vulvar anus

10. Low anomalies Males: Anocutaneous fistula
Female: Ano vestibular fistula

11. Various investigations in Anorectal anomalies
Differentiate high , intermediate or low anomaly
Presence of gas in the region of urinary bladder and vagina indicate underlying fistula.
Invertogram
RGU/MCU
To confirm level of blind bowel pouch
To demonstrate fistula
Contrast studies
Distal cologram
Direct catheterisation

12. Various investigations in Anorectal anomalies
USG
Upper urinary tract congenital anomalies CT
Bony/urinary abnormalities
Demonstrate thickness of muscles-puborectalis sling and external anal sphincter ( deficiency leads to incontinence)
MRI
Better understanding the relationship between bowel with muscles in axial, coronal and sagittal planes

13. Objectives of Contrast study
To confirm level of blind bowel pouch To confirm presence & level of fistula between Gastrointestinal & Genitourinary system. To see for associated bony abnormalities if present

14. Clinical history Procedure details
A 4 year old male, operated case for imperforate anus (Transverse loop colostomy done). On clinical examination patient had associated cleft palate and hypospadias.
Procedure details
Study was done using diluted gastrograffin given through infant feeding tube in distal stoma of colostomy and serial radiographs were taken under fluoroscopic guidance.

15. Findings
The rectum was abruptly narrowed proximal to pubococcygeal line Beaking of blind rectal pouch Acute backward angulation of posterior urethra Communicating fistulous tract between urethra and distal rectum The distal urethral opening in underside of glans penis The visualised sacral spine shows S2 hemivertebra and S4 butterfly vertebra

16. Acute backward angulation of posterior urethra communicating fistulous tract between urethra and distal rectum-rectoprostatic fistula

17. The rectum was abruptly narrowed proximal to pubococcygeal line with beaking of blind rectal pouch.

18. The visualised sacral spine shows S2 hemivertebra and S4 butterfly vertebra
Anal site marker

19. Conclusion
Distal loop cologram is useful study to confirm level of blind bowel pouch, presence and level of fistula between gastrointestinal & genitourinary system. Ano-rectal atresia is commonly associated with high rectourethral fistula in which Rectoprostatic fistula is common type. In skeletal anomalies, sacral bony abnormalities are common which can be demonstrated in plain radiograph.

20. References
Stephens FD, Smith ED. Anorectal Malformation in Children Chicago; Year Book Medical Publishers, Wangensteen OH, Rice CO, Imperforate anus-a method of determining the surgical approach, Ann surg 1930; 92:77. Cremin BJ. The radiological assessment of anorectal anomalies, Clin Radiol 1971;22:239. Silverman F (Ed). Caffey’s Pediatric X-Ray Diagnosis (8th ed)Chicago: Year Book Medical Publishers 1985; 2: Stephens FD, Smith ED, Paul NW. Anorectal malformation in children-update Birth defects 1988;24(4).