Neurocognitive and psychological functions were investigated in 35 consecutive children with arachnoid cyst (AC) and 35 healthy controls, in a study at Severance Children’s Hospital, Yonsei University College of Medicine, Seoul, Korea. Ages ranged from 5 to 15 years (mean 7.94+/-3.12); 28 males and 7 females. Locations of the AC were mainly temporal (n=22), frontal in 6, suprasellar (4), and posterior fossa (3). Tests included the Korean WISC-III, ADHD diagnostic panel, executive function, depression inventory, and anxiety scale. Intelligence scores in AC subjects were not different from controls. Internalization, anxiety, social immaturity, externalization, and aggressive behavior scores were significantly higher in AC subjects. Parenting stress in the AC group was higher than in control group. Of 28 with Sylvian location, 22 had compressed temporal lobes and 6 had compressed frontal lobes. Those with compressed frontal lobes showed more problems with sustained attention and more anxiety than the temporal lobe group. Left hemisphere AC was associated with increased anxiety compared to right hemisphere cyst. The 20 patients who required AC surgery showed no significant differences in IQ, memory or anxiety compared to the nonsurgical group. 
COMMENT. Neurocognitive function is not impaired in children with arachnoid cyst (AC), but AC in the left hemisphere, frontal location is associated with more anxiety. Symptoms of ADHD are more prevalent in children with AC .
CSF overdrainage in shunted intracranial AC. Researchers in Murcia, Spain, report 5 patients with acquired Chiari I malformation and 3 with posterior fossa overcrowding due to excessive CSF drainage in shunted intracranial AC . Symptoms related to hindbrain herniation developed after an average interval of 5 years following the shunt.