Use of magnetic resonance imaging to detect occult spinal dysraphism in infants

Abstract

<jats:sec> <jats:title>OBJECTIVE</jats:title> <jats:p>Cutaneous stigmata or congenital anomalies often prompt screening for occult spinal dysraphism (OSD) in asymptomatic infants. While a number of studies have examined the results of ultrasonography (US) screening, less is known about the findings when MRI is used as the primary imaging modality. The object of this study was to assess the results of MRI screening for OSD in infants.</jats:p></jats:sec> <jats:sec> <jats:title>METHODS</jats:title> <jats:p>The authors undertook a retrospective review of all infants who had undergone MRI of the lumbar spine to screen for OSD over a 6-year period (September 2006–September 2012). All images had been obtained on modern MRI scanners using sequences optimized to detect OSD, which was defined as any fibrolipoma of the filum terminale (FFT), a conus medullaris ending at or below the L2–3 disc space, as well as more complex lesions such as lipomyelomeningocele (LMM).</jats:p></jats:sec> <jats:sec> <jats:title>RESULTS</jats:title> <jats:p>Five hundred twenty-two patients with a mean age of 6.2 months at imaging were included in the study. Indications for imaging included isolated dimple in 235 patients (45%), asymmetrically deviated gluteal cleft in 43 (8%), symmetrically deviated (Y-shaped) gluteal cleft in 38 (7%), hemangioma in 28 (5%), other isolated cutaneous stigmata (subcutaneous lipoma, vestigial tail, hairy patch, and dysplastic skin) in 31 (6%), several of the above stigmata in 97 (18%), and congenital anomalies in 50 (10%).</jats:p> <jats:p>Twenty-three percent (122 patients) of the study population had OSD. Lesions in 19% of these 122 patients were complex OSD consisting of LMM, dermal sinus tract extending to the thecal sac, and lipomeningocele. The majority of OSD lesions (99 patients [81%]) were filar abnormalities, a group including FFT and low-lying conus.</jats:p> <jats:p>The rate of OSD ranged from 12% for patients with asymmetrically deviated gluteal crease to 55% for those with other isolated cutaneous stigmata.</jats:p> <jats:p>Isolated midline dimple was the most common indication for imaging. Among this group, 20% (46 of 235) had OSD. There was no difference in the rate of OSD based on dimple location. Those with OSD had a mean dimple position of 15 mm (SD 11.8) above the coccyx. Those without OSD had a mean dimple position of 12.2 mm (SD 19) above the coccyx (p = 0.25).</jats:p></jats:sec> <jats:sec> <jats:title>CONCLUSIONS</jats:title> <jats:p>The prevalence of OSD identified with modern high-resolution MRI screening is significantly higher than that reported with US screening, particularly in patients with dimples. The majority of OSD lesions identified are FFT and low conus. The clinical significance of such lesions remains unclear.</jats:p></jats:sec>

Dorsal midline cutaneous stigmata associated with occult spinal dysraphism in pediatric patients

“…1). These findings suggested that concurrent presence of more dorsal midline cutaneous markers, particularly a combination of a sacrococcygeal dimple and a dermal or subcutaneous fatty mass, was associated with cord tethering, in line with previous studies addressing multiple clinical indications for work-ups to detect OSD [14,22,23].…”

“…Furthermore, evidence of the presence of associated neural anomalies with isolated simple dimples has been found in the literature with very low [5,10,12] to relatively high occurrence rates [14,17]. Two studies of infants with MRI screening because of skin dimples revealed the occurrence of OSD at 22.8% (33 of 145) in the group with simple dimples within 11 mm of the coccyx [14] and at 16.7% (14 of 84) in intragluteal dimples [17]. Accordingly, a prospective study of dorsal midline skin dimples is warranted to have clear criteria to determine whether dimples are innocent or significant through pathological anatomy approaches.…”

“…Despite not generally presenting overt neurological impairments particularly in early life, OSD can lead to neurologic deterioration due to cord tethering, infective or aseptic meningitis due to epithelial-lining sinuses or dermod/epidermoids, or neural compression effects due to growing mass lesions [1,12,13]. Guidances for early screening for OSD and timely managements are warranted to prevent these complications, although the natural course of OSD has not been fully understood yet [1,13,14].…”

Diagnostic value of spinal ultrasound compared to MRI for diagnosis of spinal anomalies in pediatrics

“…Spinal magnetic resonance imaging (MRI) has been called the gold standard of screening for occult spinal dysraphism [5,6], but it is time-consuming, costly and invasive which requires sedation or general anesthesia in infants. It is highly dependent on factors affecting resolution such as patient motion, physiological motion from cerebrospinal fluid (CSF) pulsation and vascular flow [7][8][9].…”

Congenital Spinal Dermal Sinuses Long-Term Analysis at King Hussein Medical Center

“…Plain radiographs of the spine performed as the primary imaging modality (where dysraphy was not always found). All patients underwent magnetic resonance imaging, while in 7cases computed tomography (CT) was performed to further assess bone deformities (16)(17)(18)(19) Magnetic resonance imaging showed the pathology, congenital anatomical abnormality and the tract in all cases Figure3. The surgery aimed to excise the sinus tract completely, excisable skin tags, and correct the dysraphic state in the same setting (2,20,21) Surgical steps were common for all the cases.…”