CASE REPORT Disseminated subarachnoid chordoma: long-term favorable follow-up of a pediatric patient Seth Anderson & Yutaka Sato & Patricia Kirby & John M. Buatti & Arnold Menezes Received: 22 April 2011 /Revised: 10 August 2011 /Accepted: 30 August 2011 /Published online: 9 October 2011 # Springer-Verlag 2011 Abstract We describe a case of extraosseous chordoma disseminated in the subarachnoid space with favorable long-term follow-up. During work-up of headaches in a 13-year-old girl, MRI revealed multiple cystic subarach- noid masses in the posterior fossa and spinal canal. She underwent posterior fossa craniectomy and was found to have multicentric subarachnoid chordomas with positive CSF cytology. Six years after the operation and radio- therapy, the girl is without neurological deficits despite persistent multiple subarachnoid cystic masses. Keywords Chordoma . Intradural . CSF dissemination . Prognosis Introduction Chordomas are rare tumors arising from notochordal remnants and most commonly seen in the clivus and sacrococcygeal regions. Most clival chordomas are extra- dural, and bone destruction is one of the hallmarks. Intradural chordomas without bone involvement are ex- tremely rare. Extraosseous chordoma widely disseminated in the subarachnoid space in a child has not been reported in the literature. We herein report a unique case of a child with extraosseous chordoma widely disseminated in the subarachnoid space with 6 years of favorable follow-up. Case report A 13-year-old girl presented with progressive Valsalva- induced headaches of 2 years’ duration and dizziness. Physical examination revealed diminished gag response and decreased sensation to bilateral C2 distribution. She also reported dysphagia to solids and liquids. An initial MRI demonstrated multiple subarachnoid cystic lesions, which ranged in size from 2 mm to 10 mm and were hypointense on T1-weighted and hyperintense on T2-weighted MR images without contrast enhancement (Fig. 1). The cyst contents showed no dephasing artifacts caused by cerebral spinal fluid (CSF) pulsation on T2- weighted images and were more hyperintense on T2- weighted images compared to CSF. These cystic lesions were present on the cerebellar surface, prepontine cistern, cerebellopontine cistern and cervicothoracic subarachnoid spaces. No bony erosions or sessile attachments to any cysts were found. The cerebellar tonsils were herniated through the foramen magnum by 12 mm. With a working S. Anderson : Y. Sato (*) Department of Radiology 3892 JPP, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, Iowa City, IA 52242, USA e-mail: Yutaka-sato@uiowa.edu P. Kirby Department of Pathology, University of Iowa Hospitals and Clinics, Iowa City, IA, USA J. M. Buatti Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, IA, USA A. Menezes Department of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, IA, USA Pediatr Radiol (2012) 42:878–880 DOI 10.1007/s00247-011-2266-1