The role of magnetic resonance imaging in the prenatal diagnosis of cleft lip and palate.

INTRODUCTION Cleft lip and/or palate is the most common congenital craniofacial anomaly. Ultrasonography plays a key role in the early diagnosis of this anomaly and is completed by MRI. The purpose of this paper is to present and summarize the experience in diagnosis of cleft lip/palate by means of MRI. MATERIAL AND METHODS The material consists of 62 fetuses that required more detailed evaluation which was conducted with the use of a 1.5 T scanner in SSFSE/T2 sequence in the sagittal, transverse and coronal plane. RESULTS The cleft was diagnosed in 15 fetuses: an isolated cleft lip in one case (6.7%), a cleft lip and alveolar process in 2 (13.3%), a cleft lip and palate in 12 (80%). In eight fetuses (53.3%) the defect was unilateral, in 6 (40%) on both sides, in one case (6.7%) - a bilateral cleft lip and unilateral cleft palate was diagnosed. In three cases (20%), the cleft lip and/or palate defect was isolated, in 12 (80%) - it coexisted with other fetal abnormalities. MRI was less useful than ultrasound in 1 case (6.7%), in 4 cases (26.7%) it did not add any significant new information, in the remaining 10 cases (66.6%) important additional information was obtained on MRI. MRI revealed more details of the cleft in 5 cases (33.3%). In 10 fetuses (66.7%), cleft diagnosis was based on ultrasound and MRI only confirmed it. In 47 cases MRI allowed to show normal fetal faces, while there were difficulties of visualisation on ultrasound. CONCLUSIONS Prenatal MRI is a method supporting fetal ultrasound and is used to confirm/expand sonographic diagnosis, but can also change it. In the case of cleft lip and palate fetal MRI produces a better picture of the connections between the cavities, the degree of involvement of the secondary palate and cleft extent, and also helps to detect/assess other associated fetal abnormalities.