The Role of Bimanual Dissection and Dynamic Endoscopy in Endoscopic Neurosurgical Training: A Laboratory Investigation

Introduction: The use of endoscopic endonasal approaches for treating cranial base lesions has greatly evolved and spread worldwide. Intensive training is warranted to master these techniques. Usually two surgeons, one neurosurgeon and an ENT surgeon work in conjunction to achieve a specific goal. However, there is no standard technique devoted to this type of operation. One-hand versus two-hand dissection and static versus dynamic endoscopy has been successfully used for many different groups around the globe. The goal of this study is to evaluate the impact of bimanual dissection and dynamic endoscopy in endoscopic microsurgical training using a valid endoscopic training model.

Methods: Fifteen participants were randomized in three different groups and oriented to complete four different tasks in the Chicken Wing Training Model using three different surgical techniques. Their performances were recordered and blindly evaluated by a proficient endoscopic surgeon. Two scoring methods were used for objective assessment of the surgical skills: a specific-task checklist and a recognized global rating scale slightly modified for the aim of this study.

Results: The lowest scores were observed in the group that used the one-hand technique. Additionally, the time to complete the tasks was higher in this group. On the other hand, the group that used dynamic endoscopy and bimanual dissection completed the tasks in a shorter period of time and achieved the best score according to the assessment tools.

Conclusions: Many different techniques may be successfully used for endoscopic microsurgery, but the results of this study suggest that the use of dynamic endoscopy and bimanual dissection techniques in endoscopic microsurgery leads to improved surgical performance.

Video	Specific performance (maximum score: 16)	General performance (maximum score: 35)	Technique
Mean Score Mean Time:
A: 13.4 (11–16)/ 26.6 (19–35) 57m07s (26m27s – 111m53s)
B: 12.8 (10–15)/ 25.0 (19–29) 69m04s (29m44s – 183m14s)
C: 14.0 (12–16)/ 28.6 (23–35) 52m26s (28m20s – 68m51s)
Technique:
A: Static endoscopy + two-hand dissection
B: Dynamic endoscopy + one-hand dissection
C: Dynamic endoscopy + two-hand dissection
V1	11	19	A
V2	14	30	A
V3	13	22	A
V4	12	26	C
V5	15	29	B
V6	10	21	B
V7	16	35	C
V8	13	29	B
V9	15	34	C
V10	14	23	C
V11	13	27	B
V12	13	25	C
V13	13	19	B
V14	16	35	A
V15	13	27	A