K. Mochida et al., REGRESSION OF CERVICAL DISC HERNIATION OBSERVED ON MAGNETIC-RESONANCEIMAGES, Spine (Philadelphia, Pa. 1976), 23(9), 1998, pp. 990-995
Study Design. A retrospective study of cervical disc herniation using
results of repeated magnetic resonance imaging examinations. Objective
s. To clarify the cervical disc herniation morphological changes over
time in order to establish a strategy for treatment. Summary of Backgr
ound Data. In the authors' previous magnetic resonance imaging follow-
up study of patients with lumbar disc herniation, spontaneous regressi
on was observed in the sequestration-type lesions, and it was found th
at the tendency toward regression differed based on the anatomic posit
ion of extruded disc material. Methods. Thirty-eight patients with cer
vical disc herniation who underwent repeated magnetic resonance imagin
g examinations were studied. The changes over time in herniated disc s
ize were evaluated using this imaging technique. Evaluation showed the
characteristics of those in whom spontaneous regression was found, su
ch as extrusion pattern, and the clinical outcome was evaluated by sym
ptoms. Results. In 15 patients (40%), the volume of herniated material
was decreased. The interval from onset of symptoms to the initial exa
mination was significantly shorter In the regression group than in the
group that showed no change in disc herniation. By extrusion pat tern
, cervical disc herniation, which was divided into migration type on s
agittal view and lateral type on axial view most frequently exhibited
spontaneous regression. All of the patients with radicular pain and up
per limb amyotrophy were treated successfully with conservative therap
y. Conclusion. Although the possibility of the combination of hemorrha
ge and disc material could not be denied, active resorption of herniat
ed material probably occurred during the acute phase. Extruded materia
l ex posed to the epidural space may be resorbed more quickly than tha
t beneath the ligament. Vascular supply probably plays a role in the m
echanism of resorption. The phase and position of extrusion were the s
ignificant factors affecting cervical disc herniation resorption. It w
as demonstrated that examination performed during the acute phase usin
g magnetic resonance imaging is necessary for elucidation of the patho
genesis of cervical disc herniation, and that migrating, lateral-type
herniations regress so frequently that conservative treatment should b
e chosen not only for patients with radicular pain, but also for those
with upper limb amyotrophy.