MRI:
The 38-year-old male patient complained of headaches and an increasing sensation of pressure in the head. MR imaging showed a giant sylvian arachnoid cyst with massive midline displacement to the opposite side and a flattened high-parietal cortical relief.
Navigation:
In order to determine the ideal entrance point and the ideal trajectory for fenestration of the cyst, the operation is performed under neuronavigational guidance. The aim of the intervention is fenestration of the cyst to the prepontine cistern.
Postoperative MR imaging shows the wide cyst fenestration and a vigorous flow void sign between prepontine cistern and cyst. As expected, the size of the cyst decreased only slightly. However, MR imaging obtained 3 months after surgery demonstrates reduced midline shift. The cortical relief is no longer flattened. The sensation of pressure in the head resolved, but the patient is still complaining of headaches.
مركز جراحة المخ و الأعصاب جرايفسفالد 
