The “presyrinx” state: is there a reversible myelopathic condition that may precede syringomyelia?

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>Alteration of cerebrospinal fluid (CSF) flow has been proposed as an important mechanism leading to the development of syringomyelia. We hypothesize that a “presyrinx” condition due to potentially reversible alteration in normal CSF flow exists and that its appearance may be due to variations in the competence of the central canal of the spinal cord.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>Five patients with clinical evidence of myelopathy, no history of spinal cord trauma, enlargement of the cervical spinal cord with T<jats:sub>1</jats:sub> and T<jats:sub>2</jats:sub> prolongation but no cavitation, evidence for altered or obstructed CSF flow, and no evidence of intramedullary tumor or a spinal vascular event underwent MR imaging before and after intervention that alleviated obstruction to CSF flow.</jats:p></jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>Preoperatively, all patients demonstrated enlarged spinal cords and parenchymal T<jats:sub>1</jats:sub> and T<jats:sub>2</jats:sub> prolongation without cavitation. Results of magnetic resonance (MR) imaging examinations following intervention in all patients showed resolution of cord enlargement and normalization or improvement of cord signal abnormalities. In one patient with severe arachnoid adhesions who initially improved following decompression, late evolution into syringomyelia occurred in association with continued CSF obstruction.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusion</jats:title> <jats:p>Nontraumatic obstruction of the CSF pathways in the spine may result in spinal cord parenchymal T<jats:sub>2</jats:sub> prolongation that is reversible following restoration of patency of CSF pathways. We refer to this MR appearance as the “presyrinx” state and stress the importance of timely intervention to limit progression to syringomyelia.</jats:p></jats:sec>

Subacute Subdural Hygroma and Presyrinx Formation After Foramen Magnum Decompression With Duraplasty for Chiari Type 1 Malformation -Case Report-

“…These findings were consistent with presyrinx. 5) The serial neuroimaging changes suggested that infratentorial hygroma was the cause of the subsequent other complications such as hydrocephalus and presyrinx. Although the arachnoid membrane seemed to be preserved during operation, an invisible tear present in the area of FMD may have acted as a one-way valve in the postoperative period.…”

“…5) To prevent the progression of presyrinx to syringomyelia, which might cause intractable pain or persistent neurological deficits, immediate normalization of CSF circulation around the foramen magnum was warranted. 5,8) We preferred re-exploration, which offered more straightforward treatment for the re-establishment of CSF circulation. The hygroma was thought to be the result of the check-valve phenomenon, but the point of leakage was difficult to detect.…”

“…4) Presyrinx is an interstitial spinal cord edema condition that precedes syringomyelic cavity formation first characterized as a cord enlargement with T 1 and T 2 prolongation on MR imaging without cavity formation. 5,8) Presyrinx is said to be the result of CSF pathway obstruction that induces a pressure gradient. In our case, the MR imaging findings corresponded to presyrinx, and the pressure gradient resulted from CSF pathway obstruction by the subdural hygroma.…”

“…In our case, the MR imaging findings corresponded to presyrinx, and the pressure gradient resulted from CSF pathway obstruction by the subdural hygroma. 5,8) Syringomyelia can be divided into two forms, communicating and non-communicating with the fourth ventricle. 5) Communicating syrinx is found in association with hydrocephalus and is caused by obstruction of CSF circulation distal to the outlets of the fourth ventricle.…”

“…5,8) Syringomyelia can be divided into two forms, communicating and non-communicating with the fourth ventricle. 5) Communicating syrinx is found in association with hydrocephalus and is caused by obstruction of CSF circulation distal to the outlets of the fourth ventricle. Communicating syrinx primarily develops without the involvement of presyrinx.…”