Diagnosis of laryngeal dysplasia in five horses using magnetic resonance imaging and ultrasonography.

The research explores the use of Magnetic Resonance Imaging (MRI) and Ultrasonography in diagnosing laryngeal dysplasia in horses, a condition previously identified through post-mortem or endoscopy. Five horses diagnosed with this condition through endoscopy were further tested using MRI and Ultrasonography to provide an accurate ante-mortem diagnosis and permit better management strategies.

Objectives and Methods

• The primary objective of the study was to ascertain if MRI and ultrasound findings could accurately reflect the anatomical features related to a presumptive fourth branchial arch abnormality. This information could help in the accurate ante mortem diagnosis of laryngeal dysplasia and consequently, enable more appropriate care and management.
• The study was conducted at the Rood and Riddle Equine Hospital between February 2008 and January 2009. The experiment used horses diagnosed with either rostral displacement of the palatopharyngeal arch and/or right laryngeal dysfunction using upper airway endoscopy.
• Focusing on a small sample size of five horses, the researchers carried out ultrasonography and MRI of the laryngeal region to examine the condition more precisely.

Results and Findings

• All horses subjected to MRI and ultrasound examinations showed features consistent with laryngeal dysplasia. These features included the absence of cricothyroid articulation, the dorsal extension of the thyroid cartilage lamina, and the absence or hypoplasia of the cricopharyngeus muscle.
• The experiments successfully achieved the aim of the study, providing clear evidence that MRI and ultrasound could accurately confirm the diagnosis of laryngeal dysplasia.

Conclusions and Implications

• This research lays the foundation for using MRI and ultrasonography as definite methods for diagnosing laryngeal dysplasia before the horse’s death.
• The identifiable abnormalities in the upper airway through endoscopy can be characterized better using MRI and ultrasonography. This can result in more appropriate recommendations for disease management.
• Preoperative imaging may also prevent unnecessary surgical intervention, improving patient outcomes and reducing the overall cost of care.