Surgical strategy for pineal region tumors by the posterior interhemispheric transcallosal route-microsurgical anatomy and clinical study

Abstract

Objective To provide surgical strategy for pineal region lesions by the microsurgical anatomy and clinical study of the posterior interhemispheric transcallosal route.Methods The posterior interhemispberic transcallosal route was examined in stepwise dissections in 10 adult cadaveric brains after perfusion of the arteries and veins with colored silicone in 6～25 operating microscope.To measure distances of correlating structures and analyze and contrast retrospectively the clinical outcomes of 15 cases pineal region lesions using the posterior interhemispheric transcallosal route and the infratentorial supracerebellar approach.Results The surface landmarks for the approach pathway were the lambdoid suture and the direction for the approach was from lambdoid suture to the center of pineal body.The distance between lambdoid suture and the center of pineal body in cadaver brains and T2RMRI averaged 71.40 mm and 70.14 mm,respectively.11 patients in pineal region lesions were operated with infratentorial supracerebellar approach and severe disability in 1,death in 2 and tumor excision was complete in 4.4 patients were operated with the posterior interhemispheric transcallosal route and severe disability in 1,death in 0 and tumor excision was completed in all.Conclusion The choice among the surgical approaches depends on the size and the location of the lesion in the pineal area,especially its relation to the ventricular system,the median line,the splenium and the vein of Galen.MRV,DSA and T2RMRI before surgery could be helpful for the choice of surgical approaches. Key words: Pineal region tumor; Posterior interhemispheric transcallosal route; Microsurgery; Anatomy