Anterior Petrous Rhomboid Approach for Petroclival Chondrosarcoma

Access to the petroclival region has always been challenging owing to the surrounding neurovascular structures. The ideal approach to the region depends not only on the specific tumor characteristics, but also on surgeon preference. In this video article, we have highlighted the use of the modified Dolenc-Kawase approach to expand the standard anterior petrosectomy corridor for challenging tumors that need additional exposure.^1-5 A 60-year-old woman presented with facial sensory loss and occasional diplopia. On radiological investigation, a densely calcified petroclival lesion was identified (Video 1). A temporal craniotomy with zygomatic osteotomy was performed followed by deroofing of the superior orbital fissure, saucerization of the foramen spinosum, and coagulation and division of the middle meningeal artery. The temporal dura propria was then dissected off the lateral wall of cavernous sinus using a combination of sharp and blunt dissection to expose the modified Dolenc-Kawase rhomboid. A T-shaped dural incision was made along with tentorial sectioning and division of the superior petrosal sinus. Owing to dense calcification in the tumor, a bone Cavitron ultrasonic aspirator (CUSA; Integra LifeSciences, Princeton, New Jersey, USA) was used for debulking of the tumor. Tumor was removed piecemeal alternately using the bone CUSA and scissors. Tumor was dissected from above and below the trigeminal nerve that forms the center of the corridor followed by dissection off the sixth cranial nerve as it enters the Dorello canal. An endoscope may be used at the end to ensure complete removal of the tumor.