직장항문기형환아에서동반하는이분척추증 -12 예환아에대한전향적연구 김성민 1, 장혜경 2, 심규원 3, 김동석 3, 오정탁 2, 최승훈 4, 한석주 2 연세대학교의과대학외과학교실, 용인세브란스병원외과 1 연세대학교의과대학외과학교실, 세브란스어린이병원소아외과 2 연세대학교의과대학신경외과학교실, 세브란스어린이병원소아신경외과 3 연세대학교의과대학외과학교실, 강남세브란스병원소아외과 4
Introduction The association of anorectal malformations and spinal cord anomalies has been well documented Magnetic resonance imaging (MRI) has been considered as the diagnostic modality of choice for evaluation of the spine There have been numbers of studies showing the incidence of spinal dysraphism regardless of types of ARM
Purpose By examining all patients with any type of ARM with lumbosacral MRI, we aimed to evaluate the true incidence of 1.spinal dysraphism 2.tethered spinal cord requiring neurosurgery We further described the correlation between lumbosacral MRI vs. conventional methods such as sacral plain films and spinal ultrasonography (US)
Material and Method From January 22 to March 29 We prospectively performed Lumbosacral MRI examination, regardless of type of ARM, in all patients already had been evaluated with a plain X-X ray of the sacrum with and without spinal US
Material and Method Plain X-ray X film of the sacrum The morphologic abnormalities of bony sacrum eg. dysmorphism, fused vertebra, and hemisacrum For the study purpose, we measured a sacral ratio (SR) in the antero-posterior and lateral sacral film as described in the previous article * *Pena A: Anorectal malformations. Semin Pediatr Surg 4:35-47, 1995
Material and Method Spinal US Spinal US was performed whenever possible for evaluation of the spinal cord and abnormal mass lesion in lumbosacral area
Material and Method MR protocol Whole spine sagittal T2-weighted image, Lumbar spine axial and sagittal T1-,, T2- weighted image, Gadolinium-enhanced T1-weighted image (axial, sagittal) (if necessary) Pelvis axial, sagittal, and coronal T2-weighted image when the investigation of pelvic musculature is necessary Pediatric sedation unit (PSU) for safe and adequate sedation Sedation protocol :oral chloral hydrate at 1 mg/kg given for sedation before MRI patients were transferred to the PSU with a prepared midazolam am and flumazenil
Material and Method Indication of detethering surgery Operation was reserved for 1.Those who had a radiographically demonstrated lipomatous lesion in filum within the first 6 months of life 2.In case of older children, as soon as the lesion was discovered Non-operative operative follow-up with biannual MR examinations was pursued 1. The patients had non-progressive symptoms 2. Those who had only asymptomatic low conus medullaris Thickened filum terminale
Material and Method Type of anorectal defect Standards for diagnosis international classification (Krickenbeck, Germany, May 17 to 2, 25)
Result From January 22 to March 29, 142 patients underwent corrective surgery for their ARMs During the study period, 12 patients completed lumbosacral MRI evaluation and were enrolled in this study
Result There were 72 males and 48 females with male to female ratio being 1.5:1
Result Perineal fistula (PF) in 23 patients (19.2%), Vestibular fistula (VF) in 24 patients (2.%), Rectourethral fistula (RU) in 44 patients (36.7%), Rectovesical fistula (RV) in 11 patients (9.2%), Cloacal anomaly (CL) in 15 patients (12.5%), Rare/regional variants (RA) in 3 patients (2.5%). The mean (±SD) age at anorectal reconstruction was 5.9(1.9) months
Result MR finding of spinal dysraphism The mean age at MR evaluation was 3.5 months (range, 1 day to 71.7 months) Low conus medullaris was found in 25 patients (2.8%) Fatty filum or lipomatous mass lesion in caudal spine was found in 24 patients (2.%) Pure dysplastic bony sacrum in 24 patients (2.%) Hydrosyringomyelia in 13 patients (1.8%), dermal sinus tract in 3 patients (2.5%), and meningo(myelo)cele in 2 patients (1.7%)
Result
Krickenbeck Spinal Dysraphism in MRI Detethering Surgery (p=.69*) classification (p=.4) No** Yes Total Perineal fistula (PF) No 2 2 Yes 1 2 3 Total 21 2 23 Vestibular Fistula (VF) No 17 17 Yes 4 3 7 Total 21 3 24 Rectourethral Fistula (RU) No 26 26 Yes 7 11 18 Total 33 11 44 Rectovesical Fistula (RV) No 7 7 Yes 1 3 4 Total 8 3 11 Cloacal anomaly (CL) No 6 6 Yes 2 7 9 Total 8 7 15 Rare/regional variants (RA) No 3 3 Yes Total 3 3 26 patients (26/41, 63.4%) underwent detethering surgery under the diagnosis of significant tethered spinal cord
Result Correlation of plain film, spinal sonography, and lumbosacral MRI From the morphological point of view, 95 patients did not show an evidence of spinal dysraphism on sacral plain X-X ray film and spinal US Of those patients, MRI revealed an occult spinal dysraphism in 21 patients (21/12, 22.1%)
A Sacral Ratio(SR) according to the type of ARM B Sacral Ratio(SR) of patients underwent a detethering surgery 1. 1. *p<.1 Sacral Ratio.8.6.4.2.65 P=.271 Sacral Ratio.8.6.4.2.69±.13.54±.19.65. PF RA VF RU RV CL Type of ARM (Krickenbeck). Not performed Performed Detethering surgery C 1 ROC curve 8 Sensitivity% 6 4 2 Detethering No Treatment Total 2 4 6 8 1 1% - Specificity% SR>.65 SR<.65 9 17 73 21 82 38 AUROC =.73 Sensitivity 65.4% Specificity 77.7% Total 26 94 12
Conclusion The prevalence of spinal dysraphism is high in patients with ARM and is more frequent in patients with complex type ARM MRI is useful in detecting occult spinal dysraphism that may need detethering surgery in all types of ARM patients We further recommend a routine lumbosacral MRI examination in all patients with any type of ARM, especially those whose sacral ratio is lower than.6