Craniofacial malformations in prenatal ultrasound evaluation. Literature review

Abstract

Fetal face is the key anatomical location, both psychologically and clinically, for the mother and the clinician. Ultrasound prenatal examination of the maxillofacial region allows to evaluate the fetal face in the first weeks of gestation. In ambulatory intravaginal ultrasound, sensitivity of the facial defect detection is 20-30% in cases without the risk of TORCH and fetal abnormalities, which may arouse suspicion of the presence of facial malformation. Facial defects form a wide group of pathologies. Unfortunately, challenges connected with 2D and 3D ultrasound imaging cause frequent misdiagnoses in early gestation. Maxillofacial abnormalities can be solitary or they can coexist with other abnormalities or syndromes. In case of detecting a facial defect, a precise and thorough ultrasound of whole fetal body is necessary, whereas in case of detecting any fetal body abnormality a precise and thorough ultrasound examination of the fetal face is obligatory. Unfortunately, most contemporary prenatal ultrasound standards propose only the overall “face and orbits” evaluation of the fetal face. The evaluation is difficult at 23 and 24 weeks of gestation and seems to be rather challenging in the third trimester of gestation. Not only facial malformations but also facial dimorphic features may lead to the suspicion of genetic syndrome and they may be extremely important in making correct diagnosis. Attempts at standardization in fetal face ultrasound evaluation have proved to be extremely difficult. Advantages of 2D ultrasound over 3D ultrasound and 3D ultrasound over 2D ultrasound in fetal face evaluation have been a topic of much debate. Most typically, fetal face is examined with 2D ultrasound in a few basic planes: coronary, sagittal, frontal and oblique. The planes preferred in the evaluation of facial structures are discussed in details in the paper. Fetal facial defects evaluated in the ultrasound examination may be divided into a few main groups: examination of the orbit and eyeball defects, examination of the external nose and nasal cavity defects, examination of the cleft defects involving the lip, hard and soft palate which may be unilateral or bilateral, examination of external ear defects, examination of mandibular defects and detection of fetal tumors. 3D ultrasound evaluation of the fetal face is extremely useful in visualization of the face, thus presenting a problem to parents and clinicians. Prenatal ultrasound examination provides necessary and extremely useful data concerning fetal facial abnormalities, which allows to plan care and further treatment including interventions in pediatric ENT, pediatric surgery and plastic surgery areas. Cooperation of ultrasound diagnostician and clinicians taking care of a child in the future is therefore necessary when designing treatment scheme in cases of fetal facial defects.