Ehsan Alimohammadi - MD, Resident of Neurosurgery, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Guive Sharifi - MD, Associate Professor of Neurosurgery, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Mohammad Samadian - MD, Associate Professor of Neurosurgery, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Kaveh Ebrahimzadeh - MD, Assistant Professor of Neurosurgery, Shahid Beheshti University of Medical Sciences, Tehran, Iran

Background and Importance: This interesting case is about the presence of normal pressure hydrocephalus and a large pseudomeningocele at the same time after 13 months of posterior fossa surgery. Although the occurrence of a pseudomeningocele following posterior fossa surgery is not so rare, such a late large pseudomeningocele development with signs and symptoms of NPH after 13 months of surgery is rather peculiar. Case Presentation: A 59-year-old man referred to our clinic for a cerebellopontine angle tumor. The patient presented with right hearing loss and mild facial palsy. We operated the patient with retrosigmoid approach, and we discharged him after five days. After about 13 months, the patient referred to our center again with complaint of progressive bulging of previous surgical region and gait apraxia, urinary incontinence anddementia. A large pseudomeningocele in the site of previous surgery was seen. Conclusion: The authors presented a case report on late development (13 months) of a huge pseudomeningocele following vestibular schwannoma surgery with signs and symptoms of normal pressure hydrocephalus. Such a late big pseudomeningocele presentation with signs and symptoms of normal pressure hydrocephalus after posterior fossa surgery is peculiar.

Hydrocephalus; Pseudomeningocele; Intracranial; Pressure