The behavior of Pantopaque on MR: in vivo and in vitro analysis.

MR imaging is considered by many to be the procedure of choice in imaging the spinal cord; yet we encountered an important pitfall of this procedure in the form of a patient with retained intraspinal Pantopaque. The results of this case are presented as well as those obtained in another patient with retained Pantopaque. Also described is the behavior of this contrast material when using in vitro imaging data obtained from a CSF/Pantopaque phantom. When T1-weighted imaging sequences are used, Pantopaque gives a high signal and CSF gives a low signal. With long repetition time, (e.g., 4000 ms), the CSF signal is high and the Pantopaque signal is not. With repetition time around 1000 to 2000, both may be isointense. The implications of these findings are discussed.