Ultrasound Assessment of the Larynx and Trachea in the Neonatal Period

Diseases of the larynx and trachea are a heterogenous group of disorders. Witch may include congenital anatomical disorders, neoplastic changes, vocal cord paralysis of varied aetiology or narrowing of the larynx associated with long-term intubation. The multitude of disorders of these organs necessitates the continuing search for diagnostic methods which will not only provide answers to clinical questions but will also be safe and with the least level of interference with the wellbeing of the patient, which is of particular importance in the neonate.

Diagnosis of diseases of the larynx and trachea in the neonate and infant is mainly based on endoscopy, magnetic resonance imaging and computer tomography. These investigations are invasive and not infrequently require anaesthetising the patient.

In recent decades only a few studies have been reported which described the ultrasound anatomy of the larynx prior to and following intubation or that of the mobility of the vocal cords. These studies involved small groups of subjects and were performed using lower quality ultrasound devices which did not provide for unequivocal conclusions to be drawn. To date, no standards have been published concerning the size of the structures of the larynx and trachea or the mobility of the vocal cords on ultrasound examination in the neonate. Additionally, there are no recommendations which include ultrasound examination as a reliable component of the diagnosis of congenital disorders of the larynx or other diseases of this organ.

Ultrasound is a non-invasive, repeatable and safe diagnostic method, which has recently, thanks the development of technology, provided for the very accurate imaging of even small structures, as well as their assessment on dynamic examination. Furthermore, the easy availability of this examination may in the future contribute to the early diagnosis of diseases of the larynx and trachea without the need to prolong neonatal hospitalization or anaesthesia.

In addition, the use of neural networks to analyse the ultrasound images obtained will provide for the development of algorithms which could become an irreplaceable tool, not only in the diagnosis of the disorders described, but also in predicating disorders affecting their further development or functional disorders in infancy.