Hyperacute Seizure 07 - Clinical Case Summary
Hyperacute Seizure 07 - Clinical Case Summary
Hyperacute Seizure 07 - Clinical Case Summary
SummaryHistory
27 yo male with syncopal episode preceeded by dizziness. There is observed shaking and "eyes rolling back in head."
Exams Performed
MR T1-w pre and/or post contrast; MR Coronal T2-w spin echo and MR FLAIR; MR diffusion
Prior available imaging reports
CT Head was not available
T1-w MR pre and post
1. Negative post contrast head T1-w MR, other than nonaggressive maxillary sinus inflammatory disorder.
2. Nonaggressive paranasal sinus and otomastoid inflammatory changes of indeterminate clinical activity.
MR Coronal T2-w spin echo and MR FLAIR
1. There is evidence of recent seizure activity affecting the right hippocampus. There is minimally increased T2 signal and effacement of the internal myelinated tracts, but with no apparent volume increase. Based on clinical symptoms, the MR findings fit best in the hyperacute post seizure timeline caused by a minimal depth and duration event.
2. The left hippocampus appears to be within normal limits. Lower magnet field strength create some motteling (heterogeneous) parenchymal signal on both sides. However, all the left myelinated tracts are present on the left and the left hippocampal volume is normal.
MR Diffusion (DWI)
1. The MR diffusion is within normal limits.
MR susceptibility is not available
T1-w MR pre and post
1. Negative post contrast head T1-w MR, other than nonaggressive maxillary sinus inflammatory disorder.
2. Nonaggressive paranasal sinus and otomastoid inflammatory changes of indeterminate clinical activity.
MR Coronal T2-w spin echo and MR FLAIR
1. There is evidence of recent seizure activity affecting the right hippocampus. There is minimally increased T2 signal and effacement of the internal myelinated tracts, but with no apparent volume increase. Based on clinical symptoms, the MR findings fit best in the hyperacute post seizure timeline caused by a minimal depth and duration event.
2. The left hippocampus appears to be within normal limits. Lower magnet field strength create some motteling (heterogeneous) parenchymal signal on both sides. However, all the left myelinated tracts are present on the left and the left hippocampal volume is normal.
MR Diffusion (DWI)
1. The MR diffusion is within normal limits.
MR susceptibility is not available
Overall impression
1. There is abnormality within the right hippocampus. The degree of edema is limited only to the CA1-subiculum area. The hippocampal volume is not increased. However, there is effacement of the internal and external white matter tracts. Since there is little edema, this is not related to obscuring the tracts by generalized edema, but rather this is actual damage to the white matter tracts. These findings are those of a subacute phase of seizure activity with clearly abnormal, but relatively subtle changes unless the MR coronal T2-w spin echo sequence is aligned correctly and viewed with sufficient contrast windowing.
Lessons to be Learned
There is a wide variety of hippocampal changes in the hyperacute and acute timeframes depending on the depth and duration of the seizure event. When the depth and duration is significant MR findings on the coronal T2-w spin-echo sequence is readily apparent. However, when the event has a minimal depth and duration the imaging must depend on subtle changes like only effacement of the myelinated tracts, as in evidence in this case. Detection of subtle changes requires careful MR technique such that high quality coronal T2-w spin-echo imaging is obtained and performed without rotation of the patient in the scanning gantry, and is performed orthogonal to the long axis of the hippocampus. To do this the sagittal scout image is used for the plane of section.