M. De Lima Oliveira, M. Fernandes De Oliveira, K. Andrade Norremose, S. Brasil Lima, F. Campos Gomes Pinto, H. Matsushita, M. Jacobsen Teixeira, E. Bor-Seng-Shu
Department of Neurology, University Hospital, University of São Paulo – São Paulo, Brazil
Objective: Treatment of hydrocephalus is still a challenge to medicine. Currently, the retrograde ventriculo-sinus shunt (RVSS) is proposed in order to solve the question of ventricular catheterization complications related to siphoning. Transcranial Doppler can evaluate intracranial hypertension relief after this surgical procedure measuring brain blood flow velocities, pulsatility and resistivity index.
Material and Methods: We have applied RVSS in 6 patients with myelomeningocele correction, whom have shown progression of hydrocephalus with less than 6 months old. Mean age was 3 months. The blood flow velocity, pulsatility and resistivity index were measured in the middle cerebral artery before and after RVSS by transcranial Doppler. Transfontanel echography and Doppler of the superior sagittal sinus were also performed. The surgical technique involves 2 skull burr-holes under the same arcuate incision in the scalp: one in the posterior parietal bone (point Frazier) and another in the middle third of the sagittal suture. After opening the parietal dura, lateral ventricle was punctured and then a small opening was made in the superior sagittal sinus. Then the catheter was inserted approximately 2 cm in the retrograde blood flow direction.
Results: In 4 patients, cephalic perimeter percentil (CPP) improved with statistical significance, followed by clinical improvement. Doppler ultrassound evaluation revealed increase in mean velocity in the middle cerebral artery after procedure associated with decrease in pulsatility and resistence index, which were still present 1 year after the procedure. In 2 patients, continuous high pulsatility index and CPP forced a revision. Blood flow in the superior sagittal sinus was preserved after surgical procedure in all patients.
Discussion: Although still preliminary, improved hemodynamic encephalic demonstrated by transcranial Doppler was compatible with the clinical improvement of patients. Therefore, this method may be a useful tool for assessing the pre post operative brain hemodynamic in patients with hydrocephalus.
Key words: brain artery velocities, hydrocephalus, transcranial Doppler, ventricle sinus shunt.