P rimary spinal syringomyelia can be defined as syringomyelia that exists in the absence of an abnormality at the level of the foramen magnum, the most common form of which is CTE. Chiari malformation is the generally used eponym, comprising a small number of anatomical subtypes. There are similarities in the underlying pathophysiology of syringomyelia developing in the presence of CTE and primary spinal syringomyelia. At present our understanding is that in both of these conditions there is a partial obstruction of the subarachnoid space; in the case of CTE
Invited submission from the Joint Section Meeting on Disorders of the Spine and Peripheral Nerves, March 2005
Evaluation of surgical therapy by magnetic resonance imaging
T he advent of new imaging techniques in the past decade (in particular, computerized tomographic scanning with injection of water-soluble contrast medium and magnetic resonance (MR) imaging) has greatly facilitated the diagnosis of Chiari I malformation and associated syringomyelia. Indeed, MR imaging has now become the optimal technique, since it is noninvasive and permits simultaneous studies of the brain, craniocervical junction, and spinal cord. 2 As a result, this disease complex, once thought to be quite rare, is now being diagnosed with increased
In this paper the author summarizes currently available surgical approaches to spinal syringomyelia that is unrelated to Chiari I malformation or hindbrain descent. Primary spinal syringomyelia is most comonly associated with spinal trauma but is also encountered as a sequela to intradural inflammatory processes (infections or chemical), as a delayed response to surgical procedures, and in association with intra- and extradural neoplasms as well as disc protrusions. The advantages of placing a shunt are its technical simplicity and immediate reduction of syrinx size; its major disadvantages are the high rate of failure observed in long-term follow up and the difficulty in applying this technique in septated cysts. Expansion of the subarachnoid space with resection of scars has better long-term results. Patients in whom a syrinx cavity has caused a kyphotic spinal deformity may need to undergo a procedure in which the kyphotic deformity is corrected to expand the subarachnoid space. Cyst obliteration is an experimental approach that cannot be evaluated at the present time.
Jörg Klekamp, Giorgio Iaconetta, Ulrich Batzdorf and Madjid Samii
T he first surgical attempt to treat FMA is attributed to Alajouanine, et al., 2 Although several authors have listed FMA as a possible cause of syringomyelia, 1, 6, 13, 14 the 1969 publication of Appleby, et al., 3 has remained the only study exclusively devoted to this subject. This may reflect the decreased incidence of FMA-related syringomyelia as antibiotic agents and improved hygiene have reduced the rate of meningitis—tuberculous meningitis in particular. It may also, however, indicate uncertainty as to the treatment strategy or generally poor
Langston T. Holly and Ulrich Batzdorf
Intradural arachnoid cysts are relatively uncommon pouches of cerebrospinal fluid (CSF) found within the subarachnoid space. The authors present a series of eight symptomatic patients in whom syrinx cavities were associated with arachnoid cysts, and they discuss treatment strategies for this entity.
The population comprised eight men whose mean age was 50 years (range 35–81 years). All patients experienced gait difficulty, and it was the chief complaint in seven; arm pain was the primary complaint in one. No patient had a history of spinal trauma, meningitis, or previous spinal surgery at the level of the syrinx cavity or arachnoid cyst. In each patient imaging revealed a syrinx cavity affecting two to 10 vertebral levels. Posterior thoracic arachnoid cysts were found in proximity to the syrinx cavity in each case. There was no evidence of cavity enhancement, Chiari malformation, tethered cord, or hydrocephalus.
All patients underwent thoracic laminectomy and resection of the arachnoid cyst wall, and postoperative neurological improvement was documented in each case. The mean follow-up duration was 19 months (range 4–37 months). Follow-up magnetic resonance imaging demonstrated the disappearance of the arachnoid cyst and a significant decrease in syrinx cavity size in each patient.
Spinal arachnoid cysts can be associated with syringomyelia, likely due to alterations in normal CSF dynamics. In symptomatic patients these cysts should be resected and the normal CSF flow restored. The results of the present series indicate that neurological improvement and reduction in syrinx cavity size can be achieved in patients with syringomyelia associated with intradural arachnoid cysts.
Jörg Klekamp, Ulrich Batzdorf, Madjid Samii and Hans Werner Bothe
T he pathophysiology of syringomyelia related to trauma or arachnoiditis is still incompletely understood. The relevance of arachnoid changes for the development of syringomyelia in these instances has not been widely recognized. Shunting of the syrinx to the subarachnoid, pleural, or peritoneal space is still widely accepted as the treatment of choice for patients with syringomyelia caused by trauma or arachnoiditis. 2, 10, 26, 28, 39, 41, 44 This paper presents a retrospective study conducted at the Nordstadt Hospital in Hannover, Germany, and at the
Ulrich Batzdorf, David L. McArthur and John R. Bentson
C hiari malformation, sometimes also referred to as hindbrain descent or cerebellar ectopia, reportedly was first surgically treated by van Houweninge Graftdijk (1932) 35 and Penfield and Coburn (1938). 30 The condition is being diagnosed more frequently in adult patients due to the widespread use of MRI, particularly in the management of patients with headache. The association of syringomyelia with cerebellar tonsillar descent was proposed by Lichtenstein in 1949. 22 Surgical therapy for these entities has evolved over the years, but there are
Langston T. Holly and Ulrich Batzdorf
S yringomyelia is a complex disorder associated with a heterogeneous group of etiological entities including Chiari malformation, 4 spinal trauma, 6 , 8 , 9 , 13 and infection. 5 Although quite diverse, all of these conditions share one common characteristic: an alteration in the normal CSF dynamics in the spinal subarachnoid space. The exact pathophysiological mechanism involved with syrinx cavity formation remains unknown, yet it is widely accepted that syringomyelia results from at least a partial obstruction of spinal CSF flow. Reestablishment of
Langston T. Holly and Ulrich Batzdorf
M anagement of Chiari I malformations with or without associated syringomyelia continues to pose great challenges to physicians. Although the complete pathogenic mechanisms are yet to be elucidated, it is widely accepted that the descended cerebellar tonsils create craniospinal pressure dissociation and impaired CSF flow, which is a prerequisite for syrinx formation. 3, 4, 9 Consequently, the first line of surgical therapy at many institutions is CVD. The specific surgical steps in this operation continue to undergo modification as surgeons attempt to
Sandi Lam, Ulrich Batzdorf and Marvin Bergsneider
I n general, syringomyelia is thought to arise from an obstruction of pulsatile CSF flow. Chiari malformation, in which tonsillar descent obstructs the dynamic CSF movement across the craniocervical junction, constitutes the prototypical syringomyelia formation scenario. It is theorized that the rostrocaudal CSF pulse wave is misdirected into the spinal cord parenchyma. The resulting high intramural pressure and decreased subarachnoid space compliance favor the flow of fluid into the cervical spinal cord, possibly through perivascular spaces, resulting in