Spinal cord compression caused by idiopathic intradural arachnoid cysts of the spine: review of the literature and illustrated case.

Intradural spinal arachnoid cysts with cord compression are rare. When becoming symptomatic they cause variable symptoms involving gait disturbance, paraparesis or tetraparesis and neuropathic pain, decreasing significantly the patients' life quality. The extension of such cysts averages 3.7 vertebral bodies. The diagnosis is clinical and radiological with the use of MRI, CT myelography or a combination of both. The best treatment option is complete removal of the cyst. However, even when paresis is regressing there is no good recovery from neuropathic pain. Laminectomy approach can cause postoperative complications especially when the cyst(s) expand(s) in more than one level. Alternatively, a cyst fenestration can be performed, including the levels of the maximal spinal cord compression. The clinical outcome is as good as after the cyst resection enabling the patient to walk again. The neuropathic pain may persist and require medication. A clinical case is presented, and the literature is reviewed. In the present case we report a patient with intradural arachnoid cysts extending from T6 to L2 and causing severe gait ataxia as well as neuropathic pain and hypaesthesia. The spinal-cord was compressed at T8 and T12. Surgical treatment with partial cyst resection in the compressed levels with an interlaminar approach brought similar results as complete resection. The patient was able to walk without help which was not possible before surgery. The cysts' extension is impressive as well as the minimal operative procedure.