OPERATIVE TECHNIQUE 



447 



gradually deepened by means of the diathermy cautery, using the cutting 

 and coagulating currents alternately, and its edges retracted by small 

 flange retractors covered with moist lint. The incision is deepened until 

 the dilated lateral ventricle is opened (Fig. 299). The wound can now be 

 retracted sufficiently to enable the surgeon to see the bulging medial wall 

 of the ventricle covered in part by the choroid plexus. If the choroid 

 plexus is well developed and extends over the medial wall of the ventricle 



Fig. 298. — Van Wagenen's Approach 

 to the Pineal showing the Out- 

 line of the Osteoplastic Flap 

 and the Site of the Incision in 

 the Cortex. 



Fig. 299. — Sectional view of the 

 approach to a Pineal Tumour 

 through a dilated lateral 



Ventricle. 



in the region of the bulging pineal tumour, it may be coagulated with 

 the diathermy point. The medial wall of the ventricle is then gently 

 incised and the pineal tumour exposed and gradually separated from its 

 connections (Fig. 300). Absolute haemostasis is procured, and a small 

 piece of rubber dam is inserted into the incision in the brain for drainage. 

 The dura mater is replaced and held in position by a few anchoring 

 stitches. The osteoplastic flap is accurately put back in its original 

 position, and the scalp united by a double layer of interrupted sutures, 

 and a firm dressing then applied. The drainage wick is removed after 

 twenty-four hours and the stitches on about the tenth day. 



