1. Neurosurgery Division, Department of Surgery, Faculty of Medicine, Universitas Udayana, Academic Hospital of Universitas Udayana, Badung, Bali, Indonesia.
2. Neurosurgery Division, Department of Surgery, Faculty of Medicine, Universitas Udayana, Prof. Dr. I.G.N.G. Ngoerah General Hospital, Denpasar, Bali, Indonesia.
3. Department of Neurosurgery, Medical Faculty of Mataram University, West Nusa Tenggara General Hospital, Mataram, Indonesia.