Assessment of the accuracy and safety of the different methods used in mapping the frontal sinus

Introduction: Frontal sinus obliteration continues to be the gold standard for frontal disease control and is often employed as a last resort of treatment after more conservative therapies fail. Different methods of sinus mapping have been previously reported and include (1) 6-foot Caldwell radiography, (2) sinus probing, and (3) sinus transillumination. Image-guided technology was recently introduced to clinical practice, but its utility in frontal sinus mapping has not been evaluated. Objective: To assess the accuracy and safety of the previously reported methods of frontal sinus mapping and compare them with image-guided mapping. Study Design: Five cadaveric heads were used. The four mapping methods were applied to each head along five different axes of the frontal bone: 0, 45, 90, 135, and 180 degrees. The true frontal sinus margin was ascertained. Measurements were made from the true sinus limits to the margin points estimated by the four frontal sinus mapping methods. Results: The image-guided mapping method provided was the most accurate when compared with the other mapping methods (p < .01). The image-guided mapping method was also the least likely to overshoot the real margin compared with the other mapping methods (p < .001). The template method was the least Accurate and least safe method. Conclusions: Image-guided mapping is the most accurate and safest method of mapping the frontal sinus margins.