Wednesday, January 8, 2014

Cefepime-induced triphasics


This is the EEG of a patient on cefepime with AKI who got an EEG due to altered mental status and occasional myoclonus.  If you're not aware of this effect (ceftazidime does it too), then you ought to read up.  Not all that uncommon neurotoxicities include: temporospatial disorientation [96%], myoclonus [33%], and seizures [13%].
Nonetheless, this is a beautiful demonstration of triphasic waves: notice the three phases marked by the red-blue-red outlining, and the fact that they tend to march forward in time from frontal EEG leads to more posterior leads (if you don't have a purple line like the above, feel free to fold over your test booklet page).

Cerebral sinus thromboses

 

The above series was collected on a G1P0 who is 14 weeks pregnant and comes in complaining of a headache...just as you suspected, she got an eye exam showing papilledema and will be on heparin for at least 3-6 months (treating it like any old DVT).  However the key points are the images (HCT not necessary, but illustrative):
  • Top 2 images of non-contrasted HCT and T2 MRI reveal clots in both the cerebral sinuses and the deep veins (vein of Galen), as indicated by the black-centered arrows.
  • The second set of two images demonstrates the T1 sagittal and T2 axial MRI images of acute thrombosis (T1 isointense and T2 hypointense suggesting deoxyhemoglobin is present).
  • The third pair of images are found as you scroll to the R lateral sigmoid sinus to find a sausage-like occlusion, confirmed by the mean-intensity projections (mIPs) of the susceptibility-weighted imaging.
  • And, because you told the Ob/Gyn to get an MRV, you are rewarded with the answer of extensive sinus system occlusion.