Evolution of Surgical Approach and Management Strategy in Petroclival Meningiomas over 20 Years

Objectives: The study aimed to demonstrate evolution of surgical approach and management strategy in petroclival meningiomas (PCMs) in 5 periods over 20 years.

Methods: From February 1992 to February 2014, 616 cases of PCMs was surgical treated and approaches were selected according to tumors’ radiologic features and surgeons’ experience and preference.

Results: All surgical approaches were detailed in Table. Overall, presigmoid approach was the commonest used approach (n = 325, 52.8%) followed by subtemporal transpetrosal approach (n = 126, 20.5%) and subtemporal approach (n = 84, 13.6%). Before 1993, subtemporal approach (n = 12, 80%) was the most common used approach. After then, presigmoid approach was the preferred during the following 3 periods: from 1993 to 1997 (n = 33, 55.0%), from 1997 to 2003 (n = 133, 76.4%), and from 2003 to 2011 (n = 130, 50.2%). At the recent period (from 2011 to 2014), subtemporal transpetrosal approach became the dominant approach. Before 2011, we recommended observation to patients with non-total resection and WHO grade I meningiomas, and suggested radiotherapy to recurrent meningiomas. After then, we changed our strategy and recommended radiotherapy (gamma knife or linear accelerator) to patients with pathological mitosis, non-total resection, and unbenign meningiomas soon after surgery.

Conclusions: Due to the accumulation of surgical experience and improvement of understanding of surgical approaches, we verified the overwhelming advantages of subtemporal transpetrosal approach in resecting lesions predominantly in mid- and upper clival regions and medial to internal auditory meatus during the recent period. When encountering lesions mainly in mid- and lower- clivus and with invasion lateral to internal auditory meatus, the presigmoid approach was justified. Adjuvant radiotherapy should be recommended to lesions with residual particularly within cavernous sinus, pathological mitosis, or unbenign biological features.

Table 1 Surgical approach in different period

Period and approach (%)	Before 1993	1993–1997	1997–2003	2003–2011	2011–2014	Overall
Overall	15	60	174	259	108	616
Subtemporal transpetrosal	-	-	-	58 (22.4)	68 (63.0)	126 (20.5)
Subtemporal	12 (80.0)	14 (23.3)	20 (11.5)	38 (14.7)	-	84 (13.6)
Presigmoid	-	33 (55.0)	133 (76.4)	130 (50.2)	29 (26.9)	325 (52.8)
Retrosigmoid	3 (20.0)	7 (11.7)	9 (5.2)	22 (8.5)	2 (1.9)	43 (7.0)
Others	-	6 (10.0)	12 (6.9)	11 (4.2)	9 (8.3)	38 (6.2)