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Extraforaminal with or without foraminal disk herniation: reliable MRI findings
In Sook Lee1, Hak Jin Kim, Jung Sub Lee
1Department of Radiology, School of Medicine, Pusan National University, Medical Research Institute, 1-10 Ami-Dong, Seo-Gu, Busan, Republic of Korea.
AJR. American Journal of Roentgenology
|April 22, 2009
Summary
Spinal MRI reliably detects extraforaminal disk herniation using focal disk contour changes, nerve root displacement, and epidural fat obliteration. These findings aid in diagnosing herniations with or without foraminal involvement.
Area of Science:
- Radiology
- Neurosurgery
- Orthopedics
Background:
- Extraforaminal disk herniation can be challenging to diagnose.
- Accurate identification is crucial for effective treatment planning.
Purpose of the Study:
- To evaluate spinal magnetic resonance imaging (MRI) findings for diagnosing extraforaminal disk herniation, with or without concurrent foraminal disk herniation.
- To identify reliable MRI indicators for this condition.
Main Methods:
- Retrospective analysis of spinal MRI scans from 35 patients with confirmed extraforaminal or combined foraminal/extraforaminal disk herniation.
- Assessment of disk morphology, nerve root thickness changes, epidural fat obliteration, and nerve root displacement.
Main Results:
- Focal disk contour eccentricity was observed in 91% of patients.
- Nerve root thickness changes were present in 86%, and displacement in 63%.
- Obliteration of epidural fat surrounding the nerve root was a universal finding (100%).
Conclusions:
- Spinal MRI can reliably ascertain extraforaminal disk herniation.
- Key diagnostic MRI findings include focal disk contour eccentricity, epidural fat obliteration, nerve root thickness changes, and nerve root displacement.
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