Title:Az agyalapi mirigy daganatának részleges eltávolítása endoszkóp segítségével az ékcsonton keresztül kutyában - Esetismertetés
SUMMARY Background: Pituitary tumors are rare in dogs. In most of the cases these tumours are benign types, and according to the literature malignant hypophysis tumours are rare. One common form of the benign tumours is the hormone dependent adenoma. Mei et al. found a technique to remove hypophysis tumor via os sphenoidale. Radiotherapy is recommended if the diameter of tumorous tissue is more than 1 cm. Endoscopy can facilitate visualisation of the operation site. The most important phase is the pre-surgical measurement on MRI images and 3D reconstruction to plan the precise surgical approach. Damage of the sinus cavernous system has to be avoided during surgery and effective nozzle is used to remove tumour tissues. The postoperative care should include intensive laboratory investigation of water-, electrolyte- and endocrine homeostasis. Results and Discussion: Endoscope-guided transsphenodal hypophysectomy was used to reduce the size of tumorous tissue (20 x 19 x 16 mm) of pituitary gland because the owner did not want to perform radiotherapy. Surgical procedure was uneventful. After the surgical intervention on every second days neurological examination was done. 2 days after surgery the dog could eat and walk. After 3 days monitoring in hospital the dog was discharged. 2 weeks later the dog started shaking and he was excited. Laboratory examination found elevated plasma sodium level and hyperosmolarity, which were treated with hypotonic crystalloid infusions. After 6 days the dog was getting better and control MRI examination was performed. MRI examination showed a 12 x 15 x 13 mm soft tissue mass above hypophyseal fossa. The owner decided to euthanize the dog because hypernatraemia reoccurred and MRI showed remaining and recidivous tumour tissues. Dissection of the brain showed tumorous tissue around the infundibular part, pressing the hypothalamus into the dorsal direction and compressing the optic tracts. Histological examination confirmed adenohypophyseal malignant chromophob carnioma.