Diagnostic and therapeutic management of spinal arachnoid cysts

Background. The wide variety of intraspinal cystic lesions necessitates different elaborate diagnostic procedures to choose the right therapeutic management in symptomatic patients. Based on the case reports of seven patients with symptomatic spinal arachnoid cysts we discuss the aetiology, diagnostic procedures and therapeutic management of extra-and intradural spinal cysts. Method. All patients underwent MRI, Myelography and CT-Myelography during diagnostic evaluation. During surgery the cyst was resected and the communication between the cyst and the subarachnoid space was closed. Findings. Two patients were identified with intradural, five with extradural spinal arachnoid cysts. Postoperative outcome was favourable in those patients without preoperative cord damage. Interpretation. MRI is the diagnostic procedure of first choice because of its potential to demonstrate the exact localisation, extent and relationship of the arachnoid cyst to the spinal cord. Cord atrophy secondary to compression can be visualised and used for prediction of neurological outcome. Myelography and CT-Myelography (CTM) are still of diagnostic value since they might demonstrate the communication between the subarachnoid space and the cyst, which is important for surgical planning. The aim of surgical treatment is neural decompression and prevention of refilling of the cyst which is best accomplished by complete resection of the cyst and closure of the communication between cyst and subarachnoid space.