Utility of high-dose contrast enhancement for detecting recurrent herniated intervertebral disks.
OBJECTIVE
To study the utility of high-dose contrast enhancement in the detection of recurrent herniated disk fragments.


METHODS
Recurrent herniated disks were modeled in nine dogs by placing a fragment of normal autologous disk tissue in the epidural space at laminectomy. MR was performed at 30, 60, and 90 days with 0.3 mmol/kg of gadoteridol and repeated 24 hours later with 0.1 mmol/kg of gadopentetate dimeglumine. Contrast enhancement in the disk and scar tissue was measured and conspicuousness of the disk fragments assessed.


RESULTS
In 70% of the animals, disk fragments were more conspicuous with the larger dose of contrast medium than with the smaller dose. In 30% of animals the conspicuousness was approximately equal. Contrast between disk fragment and scar decreased with time elapsed since surgery, with time elapsed since contrast-medium injection, and with decreasing dose of contrast medium.


CONCLUSIONS
In the experimental model, increased conspicuousness of disk fragments was achieved with the larger dose of contrast medium. A clinical study is needed to confirm that a contrast-medium dose of 0.3 mmol/kg improves detection of recurrent herniated disks over a dose of 0.1 mmol/kg.
Department of Radiology, Medical College of Wisconsin, Milwaukee.
C
C
Nguyen
H
H
An
K C
KC
Ho
V M
VM
Haughton
T
T
Hasegawa
D000818:Animals; D002921:Cicatrix / Q000175:diagnosis / Q000473:pathology; D003287:Contrast Media; D004195:Disease Models, Animal; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D005682:Gadolinium; D019786:Gadolinium DTPA; D006571:Heterocyclic Compounds; D007405:Intervertebral Disc Displacement / Q000175:diagnosis* / Q000473:pathology; D007796:Laminectomy; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008536:Meglumine; D009942:Organometallic Compounds; D004369:Pentetic Acid / Q000031:analogs & derivatives*; D011183:Postoperative Complications / Q000175:diagnosis; D012008:Recurrence
D003287:Contrast Media; D004338:Drug Combinations; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C062402:gadoteridol; D008536:Meglumine; D004369:Pentetic Acid; D005682:Gadolinium; D019786:Gadolinium DTPA