Three-dimensional printed surgical guides for keratoma removal in horses using computed tomography or magnetic resonance imaging-based segmentation.

OBJECTIVE To report the technique, surgical approach, and postoperative features in horses treated via a 3-dimensional (3D) printed guide-assisted keratoma resection created using computed tomography (CT) or magnetic resonance imaging (MRI)-based segmentation. ANIMALS Five client-owned horses. STUDY DESIGN Short case series. METHODS Horses were placed under general anesthesia for imaging (CT and MRI) and underwent a second anesthesia for surgery. Two horses had guides created from CT-based imaging, 3 horses had guides created from MRI. Various sized nonarbored hole saws were used to create accurate and precise portals for keratoma removal. Surgical sites were managed until keratinized granulation tissue had formed and the defect was sealed with an artificial hoof wall patch. RESULTS All keratomas were successfully removed as a single piece either intact with the hoof wall or easily extracted after the hoof wall portal was created, in a surgical time between 20 and 90 min. All CT created guides fitted without issue; MRI-created guides required minor adjustments with a Dremel device for proper fit. All cases had minor debridement adjacent to P3 and circumferential lamellar tissue. All horses returned to previous level of performance 2 to 4 months postoperatively. CONCLUSION Use of 3D printed guides led to accurate targeting of keratomas with small surgical portals and short surgical times. Due to challenges with MRI-based segmentation, CT is preferred.