079. Resolution of Subdural Collections in Pediatric Patients with Sylvian Fissure Arachnoid Cysts

Authors: Amanda M. Kwasnicki, MD

Arachnoid cysts (ACs) are most often located in the middle cranial fossa, and while most arachnoid cysts are diagnosed incidentally on routine cranial imaging, some may become symptomatic. Much controversy remains regarding the management of ACs, specifically regarding the role of surgical intervention.Methods: A retrospective study was conducted of all pediatric patients ( < 18 years) who had surgical treatment of Sylvian fissure ACs diagnosed at a single neurosurgical center. Patients underwent open cyst fenestration or excision, and endoscopic approaches were excluded. Operative reports, admission history, inpatient documentation, and radiographic imaging studies were reviewed. Cyst location and size was determined based on radiologists’ report. Demographic, clinical, and radiographic characteristics were analyzed using summary statistics. Further univariate analysis to identify factors associated with cyst and subdural collection resolution were completed, followed by Cox regression analysis of time to subdural collection resolution.
Thirty-four patients with ACs who underwent craniotomy for cyst fenestration were identified: 26 (76.5%) were male, 8 (23.5%) were female. The average age at diagnosis was 8.1 +/- 5.0 years, and average age at time of surgery was 9.4 +/- 4.7 years. Thirty (88.2%) were symptomatic, and 12 (35.3%) experienced cyst ruptured before presentation. Eighteen patients had 50% or more reduction in cyst size (75.8%). The presence of a subdural collection, whether pre- or post-operatively, predicted >50% reduction in cyst size (p=0.002) and >75% reduction (p=0.022). Patients with pre-operative subdural collections from spontaneous rupture experienced faster resolution of subdural fluid than those with post-operative collections on Cox regression analysis (p=0.002).
This review presents this institution’s experience in the open surgical management of pediatric patients with Sylvian fissure ACs. The presence of subdural fluid collection post-operatively was associated with the reduction of cyst size. Furthermore, patients with pre-operative subdural collections (spontaneous rupture) experienced faster resolution of subdural fluid than those with post-operative collections.