The fetal larynx and pharynx: structure and development on two‐ and three‐dimensional ultrasound

Abstract

Objectives To present a systematic approach for evaluating the fetal pharynx and larynx based on twoand three-dimensional ultrasound (2D-US and 3D-US

Evaluation of Fetal Vocal Cords to Select Candidates for Successful Fetoscopic Treatment of Congenital High Airway Obstruction Syndrome: Preliminary Case Series

“…We here provide evidence that ultrasound might be of great help in selecting the small subset of fetuses with CHAOS due to isolated upper tracheal obstruction but otherwise normal larynx, which may benefit from fetoscopic surgery. Very recently, in line with our argument, an almost 90% successful evaluation of the fetal pharynx and larynx at 20-24 weeks' gestation by combined use of 2D and 3D ultrasound based on 5 spatial planes has been reported [13]. The authors suggest a potential role for their methodology in the evaluation and management of certain pathologies, such as CHAOS [13].…”

“…Very recently, in line with our argument, an almost 90% successful evaluation of the fetal pharynx and larynx at 20-24 weeks' gestation by combined use of 2D and 3D ultrasound based on 5 spatial planes has been reported [13]. The authors suggest a potential role for their methodology in the evaluation and management of certain pathologies, such as CHAOS [13]. …”

Reply

“…However, we used three-dimensional (Figure 6 in our study) in addition to two-dimensional (Figure 5 in our study) demonstrations to emphasize the proximity of the uvula and the epiglottis and, at the same time, the ability to recognize each of them correctly. In addition, in the rendered image of Figure 8 in our study 1 , the epiglottis is hidden below the uvula and therefore could not be demonstrated. The piriform recesses are grooves positioned on either side of the larynx.…”

Virtual fetal laryngoscopy

“…In a recent publication, Liberty et al 1 visualized fetal oropharyngeal and laryngeal structures successfully in 37% of fetuses examined between 11 and 24 weeks using two-(2D) and three-dimensional (3D) ultrasound. We believe that interpretation of such 2D and 3D images should be made with caution due to the proximity of the fetal uvula and epiglottis; the uvular 'equals sign' can be easily confused with the epiglottis.…”