Advances in prenatal ultrasound diagnosis of fetal tympanic ring anomalies.

The tympanic ring (TR) is an important component of the middle ear, and its developmental abnormalities can lead to serious consequences such as hearing loss. Prenatal identification of deep middle ear structural abnormalities, such as external auditory canal atresia, has long been challenging and has largely relied on indirect evaluation of auricular morphology. Recent advancements in ultrasound technology have enabled the prenatal detection of TR abnormalities and provided new imaging markers for earlier evaluation of external and middle ear development. This study aimed to evaluate the TR's normal and aberrant ultrasonographic and other imaging manifestations, the important genes controlling its development, and associated syndromes. These aspects are summarized in this review, which also examines the limitations of the present research and its potential for clinical use. The findings demonstrate that ultrasonography of TR is a valuable additional screening technique for fetal external and middle ear abnormalities, especially when combined with microtia evaluation, which improves the ability to predict the risk of external auditory canal atresia. However, further research is required to standardize prenatal ultrasound diagnosis, establish measurement criteria, promote the technology, and integrate multimodal imaging into clinical diagnosis. This article aims to provide a comprehensive reference for prenatal diagnosis and genetic counseling.