Technique for guttural pouch bead removal using a novel three-dimensional (3D)-printed instrument.

Overview

• This study evaluated a novel three-dimensional (3D) printed instrument designed to remove plastic beads from the guttural pouch (GP) in horses more effectively and efficiently than current lavage techniques.
• The researchers compared the new instrument’s performance with traditional lavage methods through different anatomical entry points using equine cadaver heads.

Background and Purpose

• The guttural pouch is a large air-filled sac in horses that can develop chondroids—hardened mucosal masses needing removal.
• Current removal methods typically involve lavage (washing out) but may be inefficient, time-consuming, or cause soft tissue damage.
• The study aimed to test a newly designed 3D-printed instrument that could potentially improve bead (simulated chondroid) removal.
• Hypotheses included improvements in bead removal quantity, speed, and reduced soft tissue damage compared to lavage tubes and different insertion sites.

Methods

• Study Type: Experimental study using 30 cadaveric equine heads.
• Preparation:
  • Dorsal pharyngeal recess (DPR) fenestration was performed using a transendoscopic laser to create an entry point.
  • Fifty plastic beads, each 12 mm, were placed inside the guttural pouch to mimic chondroids.
• Removal Techniques Compared:
  • Use of the custom-made 3D-printed instrument inserted through the DPR fenestration.
  • Control method using a standard lavage tube inserted through the DPR fenestration.
  • Insertion of instruments through the salpingopharyngeal ostium (SPO) for both control and 3D-printed instrument.
• Assessment Metrics:
  • Number of beads removed per procedure.
  • Number of 2-minute lavage cycles needed to remove ≥96% of beads or until three consecutive no-yield cycles.
  • Endoscopic grading of soft tissue damage resulting from the procedure.
• Statistical Analysis:
  • Used generalized estimating equations (GEE) model and Fisher’s exact test with significance defined as p < 0.05.

Results

• Bead Removal Efficiency:
  • The 3D-printed instrument removed a median of 48 beads out of 50, ranging between 0 and 49 beads.
  • Speed of removal was significantly faster with the 3D-printed device (median 24 beads per cycle) compared to control lavage tube (median 6 beads per cycle).
  • Control lavage tubes showed much lower efficiency and speed in bead removal.
• Comparison of Entry Sites:
  • No statistically significant difference in the total number of beads removed or removal speed between DPR fenestration and SPO entry methods.
• Soft Tissue Damage:
  • No difference in endoscopic soft tissue damage was observed between the 3D-printed instrument and control procedures regardless of entry site.
  • This suggests that the novel technique does not increase trauma risk.

Conclusions and Implications

• The novel 3D-printed instrument enabled quicker and more effective removal of simulated chondroids from the guttural pouch compared to traditional lavage tubes.
• DPR fenestration combined with this instrument represents a promising alternative surgical approach for chondroid removal, facilitating easier bead evacuation without increasing tissue damage.
• Findings encourage further clinical trials to assess the instrument’s utility and safety in live horses with actual chondroid disease.
• This technique could potentially improve equine guttural pouch surgery outcomes by reducing procedure time and enhancing cleanup efficiency.