Disparity between MR Imaging and Histochemical Grading in Human Intervertebral Disc Degeneration.

Lee, June Ho; Chung, Chun Kee; Kim, Hyun Jib

Original Article

Journal of Korean Neurosurgical Society 2006;39(6): 432-437.

June Ho Lee, Chun Kee Chung, Hyun Jib Kim

¹Department of Neurosurgery, Seoul National University College of Medicine, Clinical Research Institute, Neuroscience Research Institute, Medical Research Center, Seoul, Korea. chungc@snu.ac.kr
²Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam, Korea.

ABSTRACT

OBJECTIVE
In order to establish the index of degeneration, the authors performed a histochemical study with Safranin-O staining and investigated the occurrence of apoptosis in the human intervertebral disc.
METHODS
Eighteen intervertebral disc specimens surgically extracted from the patients and two additional specimens from the autopsied cases were stained with Safranin-O for proteoglycan according to a standard protocol. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling(TUNEL) was used to detect the fragmented DNA known to be associated with apoptotic cell death and classification scheme was formulated for categorization of the degree of Safranin-O staining (normal, moderate reduction, faint) by modification of Makin's histological-histochemical grading. The Kruskal-Wallis H test and Chi-square test were used for statistical analysis.
RESULTS
The statistical results showed a significant difference in the mean age between "normal" Safranin-O staining group and the others (19.3 versus 55, 43.4, p=0.021). However, there was no statistically significant correlation between Safranin-O staining and MR grading of disc degeneration. Only six of eighteen surgical specimens and none in autopsies showed positive apoptotic cells in TUNEL staining.
CONCLUSION
The determination of the degree of degeneration in surgically obtained disc tissue per se by histochemical staining or by the degree of apoptosis that corresponds to its morphologic change was not feasible.

Key Words: Disc degeneration; Histochemical grading; Safranin O; Apoptosis