Using Balloon As Tumor Model To Assist Anatomical Analysis Of Petroclival Meningioma Approaches.

Object:The authors quantitatively assessed the effects of balloon inflation as a model of tumor compression on the brainstem, cranial nerves, and clivus by measuring the working area, angle of attack, and brain shift associated with the combined petrosal, subtemporal, and medial transpetrosal approaches to the petroclival region.Method:Six silicone-injected cadaveric heads were dissected bilaterally via the combined petrosal, and transcochlear approaches. Quantitative data were generated, including key anatomical points on the skull base and brainstem. All parameters were measured before and after inflation of a balloon catheter (inflation volume 5 ml, 10ml) intended to mimic tumor compression.Result:Balloon inflation significantly shifted (p <0.001) the brainstem and cranial nerve foramina (displacement of upper brainstem, 9.8±1.1 mm; trigeminal nerve, 6.95±2.3 mm; facial nerve, 9.45±2.9 mm). The area of exposure at the petroclivus was significantly greater with balloon inflation (10ml: 346.5±42mm~2 ) than without ( 322.7±11.8mm~2),p<0.001.Conclusion:This study adds an experimental component to the emerging field of quantitative neurosurgical anatomy. Balloon inflation can be used to model the effects of a mass lesion. Through analysis the approaches to petraclival region, May be helpful in selecting a surgical approach to increase the working space for resection of certain extra axial tumors. Objective: To discuss effects of using subtemporal, medial transpetrosal approach to treat petroclival meningiomas by evaluation and analysis 22 clinical cases.Method: This series represents our experience with 22 clinical cases of petroclival meningiomas resected between March 2008 and March 2010 using subtemporal, medial transpetrosal approach.Result: All patients underwent head CT & MRI review postoperative. Gross total resection(GTR) was achieved in 54%,and subtotal resection(STR) was achieved in 23%, the remain 23% was partly resection(PR). There was no patients died during and after surgical procedure.Conclusion: Subtemporal, medial transpetrosal approach is a viable alternative approach to treat small or middle size petroclival meningiomas. And we also recommend selectively choose different approach under individual condition to pursusing a lower neurological morbidity and a better outcome.