Intracranial translucency as a sonographic marker for detecting open spina bifida at 11–13(+6) weeks scan: Our experience

AIMS AND OBJECTIVES: The fourth ventricle, seen as intracranial translucency (IT) at 11–13(+6) weeks, has been reported to be obliterated in cases of open spina bifida (OSB). Our aim was to assess its role in detecting OSB at 11–13(+6) weeks. MATERIALS AND METHODS: This prospective study was conducted at foetal medicine unit from January 2014 to June 2015. All women who underwent both first and mid-trimester scan in our unit were included in the study. IT was categorized as normal, obliterated or not clear. Spine was examined during both scans. RESULTS: Totally, 341 cases were included in the study. IT was found to be obliterated in four cases and not clear in one case. There was demonstrable OSB at 11–13(+6) weeks in two cases, at 15–16 weeks in two cases and at 24 weeks in one case. In the remaining 336 cases with normal IT, spine was found to be normal at target scan. CONCLUSION: Mid-sagittal view of face that is routinely used to measure nuchal translucency (NT) can also be used to detect OSB. It is feasible to integrate IT into the routine 11–13(+6) weeks scan.