TY - JOUR
T1 - Clinical significance of imaging and histological characteristics of filum terminale in tethered cord syndrome
T2 - Clinical article
AU - Thompson, Eric M.
AU - Strong, Michael J.
AU - Warren, Garth
AU - Woltjer, Randy L.
AU - Selden, Nathan R.
PY - 2014/3
Y1 - 2014/3
N2 - Object. The pathophysiology of tethered cord syndrome (TCS) is uncertain; however, it has been suggested that fibrous and fatty elements within the filum terminale (FT) play a role. The objective of this study was to describe the radiological and histological features of the FT in TCS and determine if there are associations between those features and clinical outcomes, complications, and urodynamics. Methods. In this retrospective study, histological, MRI, and clinical data obtained in 293 patients with TCS who underwent FT transection were reviewed and analyzed in a multivariate analysis. Results. The median patient age was 4.9 years (range 0.3-64.3 years). On MRI, a fatty filum was present in 65% of patients and a thickened filum (> 2 mm) was seen in 45%. Histologically, the FT contained prominent fibrous tissue in 95%, nerve twigs in 79%, adipose tissue in 59%, and vascular tissue in 36%. Histological features associated with a thickened filum on MR images were adipose tissue (OR 3.5, p < 0.001), nerve twigs (OR 2.2, p = 0.028), and vascular tissue (OR 0.5, p = 0.025). Adipose tissue was associated with a conus level below the L2-3 disc space (OR 2.3, p = 0.031) and with a fatty filum on imaging (OR 9.8, p < 0.001). Nerve twigs were associated with abnormal urodynamics (OR 10.9, p = 0.049). The only variable predictive of clinical improvement was conus level; patients with conus levels caudal to L-2 were less likely to improve postoperatively (OR 0.3, p = 0.042). Conclusions. Fibrous tissue was ubiquitous and may be important in the pathophysiology of TCS. Nerve twigs and adipose tissue were associated with abnormal urodynamics and low-lying coni, respectively. Although the majority of patients clinically improved, patients with normal conus levels had significantly better outcomes.
AB - Object. The pathophysiology of tethered cord syndrome (TCS) is uncertain; however, it has been suggested that fibrous and fatty elements within the filum terminale (FT) play a role. The objective of this study was to describe the radiological and histological features of the FT in TCS and determine if there are associations between those features and clinical outcomes, complications, and urodynamics. Methods. In this retrospective study, histological, MRI, and clinical data obtained in 293 patients with TCS who underwent FT transection were reviewed and analyzed in a multivariate analysis. Results. The median patient age was 4.9 years (range 0.3-64.3 years). On MRI, a fatty filum was present in 65% of patients and a thickened filum (> 2 mm) was seen in 45%. Histologically, the FT contained prominent fibrous tissue in 95%, nerve twigs in 79%, adipose tissue in 59%, and vascular tissue in 36%. Histological features associated with a thickened filum on MR images were adipose tissue (OR 3.5, p < 0.001), nerve twigs (OR 2.2, p = 0.028), and vascular tissue (OR 0.5, p = 0.025). Adipose tissue was associated with a conus level below the L2-3 disc space (OR 2.3, p = 0.031) and with a fatty filum on imaging (OR 9.8, p < 0.001). Nerve twigs were associated with abnormal urodynamics (OR 10.9, p = 0.049). The only variable predictive of clinical improvement was conus level; patients with conus levels caudal to L-2 were less likely to improve postoperatively (OR 0.3, p = 0.042). Conclusions. Fibrous tissue was ubiquitous and may be important in the pathophysiology of TCS. Nerve twigs and adipose tissue were associated with abnormal urodynamics and low-lying coni, respectively. Although the majority of patients clinically improved, patients with normal conus levels had significantly better outcomes.
KW - Fibrous tissue
KW - Filum terminale
KW - Histology
KW - MRI
KW - Spine
KW - Tethered cord syndrome
KW - Urodynamics
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U2 - 10.3171/2013.12.PEDS13370
DO - 10.3171/2013.12.PEDS13370
M3 - Article
C2 - 24404969
AN - SCOPUS:84895441404
SN - 1933-0707
VL - 13
SP - 255
EP - 259
JO - Journal of Neurosurgery: Pediatrics
JF - Journal of Neurosurgery: Pediatrics
IS - 3
ER -