Spinal dysraphism with anorectal malformation: lumbosacral magnetic resonance imaging evaluation of 120 patients.
OBJECTIVE
We evaluated the prevalence of spinal dysraphism (SD) in patients with anorectal malformation (ARM) by magnetic resonance imaging (MRI).


METHODS
From January 2002 to March 2009, 120 patients with ARM who underwent anorectal reconstruction were evaluated for SD with sacral plain film, spinal ultrasonography (US), and lumbosacral MRI. We adopted Krickenbeck international classification of ARM.


RESULTS
Spinal dysraphism was present in 41 (34.2%) of 120 patients with ARM, 3 (13.0%) of 23 patients with perineal fistula, 7 (29.2%) of 24 patients with vestibular fistula, 4 (36.4%) of 11 patients with rectovesical fistula, 18 (40.9%) of 44 patients with rectourethral fistula, and 9 (60.0%) of 15 patients with cloacal anomaly (P = .04). Among 41 patients having SD detected by MR, 26 patients (26/41; 63.4%) underwent detethering surgery for tethered spinal cord. The mean sacral ratio (SR) in patients who underwent detethering surgery (0.54 +/- 0.19) was significantly lower than in patients who did not undergo detethering surgery (0.69 +/- 0.13; P < .001). The optimal cutoff for the SR value predicting SD requiring detethering surgery was 0.605, with sensitivity of 65.4% and specificity of 77.7%.


CONCLUSIONS
Spinal dysraphism is common in patients with ARM, and its prevalence is higher in patients with complex ARM. Spinal anomalies can occur even with benign types of ARM and, therefore, that all patients should be screened. Magnetic resonance imaging is useful in detecting occult SD that may be missed by conventional radiologic evaluation, physical examination, and spinal US. We further recommend a lumbosacral MRI examination in those whose SR is lower than 0.6.
Kim
Seong Min
SM
Department of Surgery, Yongin Severance Hospital, Yonsei University College of Medicine, Yongin, South Korea.
Chang
Hye Kyung
HK
Lee
Mi Jung
MJ
Shim
Kyu Won
KW
Oh
Jung Tak
JT
Kim
Dong Seok
DS
Kim
Myung Joon
MJ
Han
Seok Joo
SJ
D001003:Anal Canal / Q000002:abnormalities*; D002675:Child, Preschool; D004065:Digestive System Abnormalities / Q000453:epidemiology; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007412:Intestinal Fistula / Q000453:epidemiology; D008161:Lumbosacral Region; D008279:Magnetic Resonance Imaging; D008297:Male; D009436:Neural Tube Defects / Q000175:diagnosis / Q000453:epidemiology / Q000601:surgery; D015995:Prevalence; D012372:ROC Curve; D012007:Rectum / Q000002:abnormalities*; D056910:Republic of Korea / Q000453:epidemiology; D016135:Spinal Dysraphism / Q000175:diagnosis* / Q000453:epidemiology* / Q000601:surgery