Magnetic resonance imaging is the newest technological investigation for spinal pathology, especially offers several advantages over methods of evaluating causes of low back pain and sciatica. We reviewed seventy-nine patients with surgically
confirmed
lumbar disc herniation at 96 level which were studied retrospectively to compare the diagnostic accuracy of magnetic resonance imaging between March, 1994 to May, 1995. There were 60 men and 19 women, averaging 35 years of age with range of 18 to
64.
Disc herniation classified into three group, namely, protruding (PD), extruding(ED), sequestered (SD) by MRI. The operatively confirmed location of herniated disc was compared with MRI. All studies were evaluated by one radiologist who had no
knowledge
of clinical findings or other diagnostic test results.
For protruding disc, there was 87% sensitivity, 83% specificity, 94% accuracy for MRI in distinguishing from other forms of lumbar disc herniation. There was 92% sensitivity, 88% specificity, 94% accuracy for extruded disc and 89% sensitivity,
99%
specificity, 89% accuracy for sequestered disc.
The relatively high rate of MRI accuracy could be due to technique of using a smaller slice thickness with no gap between slice, a 1.5 Tesla field strength that allow better resolution and more accurate interpretation of study.
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