{'fraction_non_alphanumeric': 0.027481772293886708, 'fraction_numerical': 0.01962983735277622, 'mean_word_length': 4.946666666666666, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
An Extremely Rare Association of Posterior Fossa Arachnoid Cyst with Chiari I Malformation and Syringomyelia in a Child: A Short Report

tonsils were displaced far inferiorly, a simple tonsillar coagulation did not suffice, and hence subpial resection of the tonsils was performed with clear egress of CSF being obtained at the end of surgery. This was followed by duraplasty. Postoperatively, Arachnoid cysts are benign, congenital, intra-arachnoid lesions. Posterior fossa arachnoid cyst associated with Chiari I malformation and syringomyelia is rare with none reported in children [1–3, 5–9] . Authors report the first of such an association in a 5-year-old child. A 5-year-old boy presented with suboccipital headache, neck pain and mild gait disturbance of 6 months’ duration. Neurological examination was unremarkable. He had undergone ventroperitoneal shunting 2 years previously at the referring hospital. MRI revealed a supracerebellar arachnoid cyst with severe tonsillar herniation up to the C 3 level and C 7 –T 10 level syringomyelia. Ventricles were adequately decompressed, and there was no communication of the cyst with the fourth ventricle ( fig. 1 a–c). Dynamic radiographs of the craniovertebral junction ruled out any bony instability. A 3 × 4 cm suboccipital craniectomy in addition to a C 1 , C 2 laminectomy was done. A large supracerebellar cyst containing CSF was present displacing both tonsils up to the C 3 level. The initial dissection focused on the cyst itself, and excision of the posterior wall of the arachnoid cyst was performed. The anterior wall was found to adhere to the surrounding structures, and hence it was only partially removed. As the Received: June 27, 2014 Accepted after revision: January 3, 2015 Published online: October 14, 2015