RT Journal Article SR Electronic T1 TM3-6 Symptomatic intracranial arachnoid cysts: a centre series JF Journal of Neurology, Neurosurgery & Psychiatry JO J Neurol Neurosurg Psychiatry FD BMJ Publishing Group Ltd SP e16 OP e17 DO 10.1136/jnnp-2019-ABN.52 VO 90 IS 3 A1 Perera, A A1 Rajashekar, D A1 Pereira, E A1 Shtaya, A YR 2019 UL http://jnnp.bmj.com/content/90/3/e16.3.abstract AB Objectives To study the presentation, management and outcomes of symptomatic intracranial arachnoid cysts.Design Retrospective records review.Subjects All cases coded as intracranial cysts.Methods Patients admitted between Jan-2012 and Sep 2017. Of 56 cases, only 24 were arachnoid cysts. Median age 57 (range 8–81). Mean 49.1±5.0 years, 8 males and 16 females.Results Males were significantly younger (34.3±9.1 vs 56.5±5.2 year-old, p=0.03) and outnumbered females. Mean size of cysts was 58.8±6.1 mm (range 18.5–126 mm). Five were located frontally, one fronto-temporal and another fronto-parietal, two parietal and two parieto-occipital, two within third ventricle, one intraventricular, one supra sellar and one intra sellar while eight were posterior fossa. 12 patients had headache, five presented with cognitive and memory issues, five had visual problems, four with limb weakness and two had cerebellar signs. Eight had open fenestration, five endoscopic fenestration, four had aspiration with reservoir, two aspiration only, two marsupialisation, two received ICP monitor and one had no treatment. One reservoir was aspirated three times and another open fenestration had another surgical fenestration. Two had transient infection, two needed VP shunts and one had cysto-peritoneal shunt. mRS (0–2) improved significantly after the treatment (62.5% pre-surgery to 91.7% post-surgery, p=0.016).Conclusions Symptomatic arachnoid cysts are more common in young males. In the literature, the most common location is middle cranial fossa which is not the case in symptomatic arachnoid cysts as in our series. Although intervention is variable, they are associated with very good outcomes.