Magnetic resonance imaging anatomy of the normal equine larynx and pharynx.

This research paper explores the use of magnetic resonance (MR) imaging to study the normal anatomy of horse (equine) larynx and pharynx, including the optimal techniques and potential limitations involved in this approach.

Objective and Methodology

• The researchers aimed to outline the normal magnetic resonance imaging anatomy of the equine larynx and pharynx, and present the best application approach for this examination technique.
• Two horses were used for this study, and the MR imaging was carried out using a 0.3 Tesla unit. The imaging protocol included sagittal and transverse T2-weighted (T2w) fast spin echo, transverse T1-weighted (T1w) spin echo, and dorsal high-resolution T1w gradient echo sequences. Both pre- and postcontrast enhancement sequences were conducted.

Procedure and Key Findings

• At the end of the imaging procedure, euthanasia was performed and a comparative study between the MR images and the gross anatomy of the dissected body parts was conducted.
• There was a clear differentiation of anatomical structures, including the soft tissues. Crucial structures such as the laryngeal cartilages, hyoid apparatus, and upper airway muscle groups, along with their attachments, could be clearly identified with the MR imaging procedure.
• However, it was occasionally challenging to distinguish individual muscles in each plane. The use of T2w and T1w in the transverse sequences was found to be most effective.
• The application of a contrast medium intravenously was found helpful to identify blood vessels. The MR images were in alignment with the macroscopic anatomy of the dissected samples.

Conclusion

• The findings of this study validate the effectiveness and precision of magnetic resonance imaging in studying the normal anatomy of the equine larynx and pharynx. Despite some limitations, such as the occasionally difficult delineation of individual muscles, the procedure shows a high degree of accuracy, particularly when the transverse sequences of the MR imaging are used.