Comparative Anatomical Study Of Different Surgical Approaches In Pineal Region And Posterior Part Of The Third Ventricle Tumor

The purpose of this experiment is simulated the Poppen approach,Krause approach and the transcallosal-interfornical approach in specimens,and discuss the important structure of pineal region and the posterior part of the third ventricle and the relationship between them in detail,to provide the basis and experience for the three approaches,and to understand the indications and advantages and disadvantages.1 The Poppen approach is suitable for tumors originating from the tentorial edge or above,and the lesions were confined to one side,as well as the tumor does not invade the offside and the posterior cranial fossa.This approach can also remove the tumor on the superior vermis and corporis callosi splenium.This approach is particularly useful for the Galen vein and its branches were located in the lower part of the lesion.Moreover,the bridging veins of occipital lobe were rarely drained to lateral sinuses and superior sagittal sinus,so the Poppen approach is superior to the Krause approach in the protection of the bridging vein.But it is difficult to removal the tumor on the contralateral quadrigeminal area and thalamus.Meanwhile,when the tumor grows downward,the gap between the veins of the deep venous system is not fully open.So the application of this surgical approach is not appropriate.2 Krause approach is suitable for the location of the tumor was poster and the diameter of the tumor is minor the 20 mm,especially suitable for the main body of the tumor located below the extension line of the straight sinus,as well as the upper bound does not exceed this line10 mm,and the tumor is locater the midline,both sides of the distance from the midline is less than 30 mm.Because the Krause approach is not easy to reveal the deep part of the cerebellum midbrain crack,so most of the tumor is located above the tentorium cerebelli,or the lesion grows into the third ventricle,it is difficult to apply Krause approach total resection of lesions.Krause approach can be divided into median and paramedian approach.To compare them,it is found that the paramedian approach is better for the protection of the bridging vein,and more easy to be removed lesion located in ipsilateral side of superior colliculus,inferior colliculus,the notch clearance.But when the Galen vein and its branches is located beneath the lesion,it is a contraindication of Krause approach.3 The transcallosal-interfornical approach is suitable to treat the tumor on the anterior and central of the third ventricle,especially suitable for the tumor located behind the foramen.When the lesion is large and mainly located in the posterior part of the third ventricle and quadrigeminal cistern below,due to the obstruction of the Galen vein and its branches,it is difficult to completely remove the lesion.Because of the number of veins to the sagittal sinus in the anterior frontal lobe was relatively small,so it is relatively well for the protection of bridging veins.