Ultrasound-assisted collection of cerebrospinal fluid from the lumbosacral space in equids.

This research outlines a method for collecting cerebrospinal fluid from the lumbosacral region in horses using ultrasonographic landmarks, highlighting that the procedure is consistently successful and minimizes the risk of trauma or contamination for the animals.

Introduction and Methods

• The study was conducted on 37 horses, where 27 had neurologic disease, and 10 had nonneurologic disease.
• They used the ultrasonographic landmarks for collecting the cerebrospinal fluid (CSF) from the lumbosacral region of the horse’s spine.
• For some of the horses (n=17), CSF was collected while they were sedated and standing. The other horses (n=20) were lying on their side (laterally recumbent), either sedated or immediately after euthanasia.
• In both cases, the horses were sedated using detomidine hydrochloride and butorphanol tartrate, and restrained with a twitch (a device used to calm horses during certain situations).

Procedure and Findings

• During the procedure, the researchers recorded several factors – including the height at the shoulders, body weight, depth of the spinal needle (used to collect the CSF), the number of attempts to collect CSF, and conducted a cytologic evaluation of the collected CSF.
• The CSF collection was most successful (in 35 of 37 cases) when the puncture was made cranial to the cranial border of the most superficial location of both tuber sacrale (bony protrusions on the horse’s pelvis) along the spine’s midline.
• In two cases, anatomical abnormalities in the horses prevented successful CSF collection.
• The researchers usually needed to attempt CSF collection only once per horse (an average of 1.1 times). They found that the horse’s height and body weight strongly influenced the depth of needle required for successful CSF collection.
• For horses that were lying on their side during the procedure, the researchers observed pelvic and sacral displacement which resulted in inconsistencies of the spine’s midline view. Despite this, they were generally able to align the spinal needle on the midline of the lower part of the vertebral column.

Conclusions

• The study concluded that ultrasound was an efficient tool that helped locate the appropriate location for CSF collection from the lumbosacral space in horses, with reduced risk of multiple attempts, trauma, and potential contamination.