Measurement of safety range in primary nasal transsphenoidal approach for pituitary surgery.

Although primary nasal transsphenoidal approach of pituitary surgery is widely used, no previous reports have determined the safety range of the surgery. The aim of our study was to clarify the medical reference range of safety angles and distances. One hundred forty-four (49 males, 95 females) participated in this study anonymously. We measured 4 parameters to achieve our goals, and the results are as follows: Angle 1 was 11.08 degrees for men and 11.31 degrees for women. Distance 1 was 17.22 mm for men and 16.46 mm for women. Angle 2 was 9.03 degrees for women and 8.73 degrees for men. Distance 2 was 14.54 mm for men and 14.10 mm for women. Angle 1 was 8.57 degrees for young, 8.93 degrees for adult, and 9.24 degrees for old. Distance 1 was 13.73 mm for young, 14.47 mm for adult, and 14.43 mm for old. Angle 2 was 11.24 degrees for young, 11.33 degrees for adult, and 11.10 degrees for old. Distance 2 was 16.86 mm for young, 16.90 mm for adult, and 16.39 mm for old. The differences in all 4 parameters were not statistically significant in comparison of sex and ages (P > 0.01). Hence, the 4 parameters that we determined contribute to the safety of the primary nasal transsphenoidal approach in pituitary surgery.