Assessing Curved Foraminotomy Rongeurs as an Effective Tool in Osteotomy Formation during Endoscopic Dacryocystorhinostomy.

Abstract

Purpose: To form an osteotomy in endoscopic dacryocystorhinostomy (endo-DCR); the thickness and angulation of the frontal process of the maxilla is a limiting factor often necessitating the use of powered instrumentation. Curved foraminotomy rongeurs might enhance surgical access and improve ostium formation.

Methods: Endo-DCRs were performed by ophthalmic surgeons on 24 sides of 12 fresh frozen cadavers in an anatomy laboratory. Once the biggest possible ostium had been created with standard rongeurs, surgeons switched to curved foraminotomy rongeurs to further enlarge the ostium. At each change of instrument, all removed bone was weighed, and an experienced surgeon evaluated the percentage of lacrimal sac exposure. Wilcoxon signed-rank test determined if the curve rongeurs facilitated any significant difference in bone removal or sac exposure.

Results: Straight rongeurs removed a median of 229.5 mg (195.2-276.5) of bone, with 60% (50-63.3) of the lacrimal sac exposed. With the addition of curved rongeurs during the same DCR, a median of 449.5 mg (380.5-589.2, P < 0.0001) of bone was removed, and 90% (78.8-100, P < 0.0001) of the lacrimal sac was exposed.

Conclusion: There is a significant improvement in the amount of bone removed with the addition of curved foraminotomy rongeurs during endo-DCR, with greater exposure of the lacrimal sac. This demonstrates a promising advance in endo-DCR surgical instrumentation.