Tag Archives: PRES

9/21 Wednesday case presentation with JLo: PRES

A elderly man with a pmh of diabetes, CKD, HTN, HLD and hx of splenic inf CAD with dilatation of his coronary arteries who presented with 2 days of severe, new onset headache and worsening vision changes.  Initial CT demonstrated bilateral occipital hypodensities ? stroke.  MRI confirmed ischemic stroke.
-DDx in this case was broad.  The headache was highly suggestive of a non-ischemic etiology.  Ischemic strokes normally do NOT present with headache.  Additionally, the broad distribution of the findings on CT scan suggested the possibility of a vasculitic process.
-DDx included ischemic stroke, PRES, and vasculitis
-PRES typically presents with: headache, seizures, visual disturbances, and altered consciousness – this patient met 2/4 of these criteria
-Kozak’s rads tips –> Acute ischemic stroke on DWI MRI will appear as hyperintense “bright”.  Ischemic stroke on ADC mapping ischemia will  will be dark “hypointense”.  PRES will have opposite imaging characteristics.

7/11 Morning Report w/ Theresa Kuo: An unexpected case of PRES

An elderly male presents with episodic confusion, vision loss, and elevated BP in the setting of methamphetamine use, ultimately found to have PRES. After doing more reading, it seems that the only atypical feature of this patient’s case was the lack of headache; the absence of overt hypertension is actually not that rare.
*Take home points: 1) Think of PRES (or RPLS) in a patient with confusion, visual changes, seizure, and headache and order a brain MRI; 2) Frank hypertension NOT required for diagnosis, it’s been noted that the episode of hypertension can precede the neurologic syndrome by 24h!; 3) Know the general MRI findings consistent with this diagnosis*
-Definition of PRES (posterior reversible encephalopathy syndrome) or RPLS (reversible posterior leukoencephalopathy syndrome)
*A clinical radiographic syndrome of headache, confusion, visual changes, and seizures a/w posterior cerebral white matter edema on MRI
*Overt hypertension NOT required for diagnosis (often BP is above baseline but may not be obviously high)
*Remains unclear; thought 2/2 disordered cerebral autoregulation and endothelial dysfunction which can be triggered by hypertension (elevated from baseline, elevation may precede neurologic syndrome by 24 hours or longer), eclampsia, meds (many for immunosuppresion), or without clear cause
*Neuroimaging is central; can be seen on CT but MRI is best
*MRI findings:  symmetrical white matter vasogenic edema in posterior cerebral hemispheres. DWI is key for distinguishing PRES from stroke(vasogenic edema is hypo or iso-intense, whereas infarct produces hyperintensity on DWI – nice catch Shawn!)
*Findings not specific, may be seen post-seizure or other neurologic conditions
*Imaging is often repeated to confirm reversibility
*Lower blood pressure, even if seemingly normal
*Withdraw offending agents
*Expect clinical and radiologic recovery in 2 weeks