Spinal arachnoid cysts in general are not a common clinical entity. When encountered, they are usually seen in the extradural or the intradural–extramdeullary location.Intramedullary primary spinal arachnoid cysts are extremely rare and only few cases have been published in the medical literature.

We report a case of a primary thoracic intramedullary spinal arachnoid cyst in an adult male who was successfully operated at our center.