Catheter Angiography, MR Angiography, and MR Perfusion in Posterior Reversible Encephalopathy Syndrome

Patient 10 is a 27-year-old man with a history of drug and alcohol abuse with a necrotic pneumonia and empyema growing Pseudomonas and Klebsiella. He developed altered mentation and an asymmetric neurologic examination with blood pressures ranging between 130/77 and 130/100 mm Hg. A, Axial MR imaging (FLAIR sequence) demonstrates extensive vasogenic edema in the occipital lobes (open arrows) and temporooccipital junction (arrowheads) consistent with PRES. Additional extensive areas of vasogenic edema consistent with PRES judged vasogenic edema grade 4 were present in the frontal and parietal lobes (not shown). B, Vertebral catheter angiogram obtained after development of occipital hemorrhage (5 days after initial toxicity) demonstrates areas of vessel narrowing and dilation along with a string-of-bead appearance and areas of focal spasm in parietal and occipital branches of the PCA. Right common carotid catheter angiogram (not shown) also demonstrated extensive vasospasm in branches of the ACA and MCA. C, MR angiogram obtained 5 days after catheter angiogram (10 days after initial toxicity) demonstrates persistent vessel irregularity in the posterior cerebral branches (arrows) with a pattern nearly identical to the appearance of the catheter angiogram. Follow-up MR imaging demonstrated improvement of the extensive vasogenic edema.

Patient 16 is a 39-year-old woman status post bowel resection and appendectomy for Crohn disease being maintained on antibiotics and steroids with baseline blood pressure of 100/60 mm Hg. Brain imaging was obtained when she developed headache, vertigo, and moderate elevation in blood pressure (145/95 mm Hg). A, Axial MR imaging (FLAIR sequence) results demonstrate vasogenic edema in occipital lobes (open arrows) consistent with PRES. Additional areas of vasogenic edema consistent with PRES were present in the frontal and parietal regions, and abnormality of signal intensity with restricted diffusion was also present in the medial right cerebellar hemisphere (not shown). B, MR angiogram obtained 1 day after toxicity demonstrates marked vessel irregularity in the PCAs bilaterally (arrows), greater on the right than on the left. C, Left vertebral catheter angiogram (selected posterior magnified lateral view) demonstrates a beaded appearance (arrow) and focal vasoconstriction and vasodilation (arrowhead) of right third- and fourth-order branches of the PCA along with a beaded appearance of the branches of the distal medial posterior inferior cerebellar artery on the left (open arrow). D Results of follow-up MR angiogram obtained 3 days after initial study demonstrate normalization of the vessel irregularity and marked improvement in vessel caliber (arrows) consistent with reversal of the vasospasm/arteritis confirmed on conventional angiography. Follow-up MR imaging demonstrated reversal of the PRES pattern.

Patient 34 is a 56-year-old woman with long-standing sickle cell disease and a baseline blood pressure of 140/60 mm Hg in a sickle cell crisis with new-onset pneumonia. She developed altered mental status and a seizure with blood pressure at toxicity of 170/110 mm Hg. A, Axial MR imaging (FLAIR sequence) demonstrates typical vasogenic edema in the occipital pole regions bilaterally (open arrows) consistent with PRES and judged edema, grade 3. Occipital lobe rCBV relative to a healthy reference cortex was 63% on the right and 54% on the left. B, Collapsed view of the 3D TOF MRA sequence demonstrates both focal vasospasm (arrows) and pruning of the PCAs bilaterally. Foreshortening of the PCAs and only partial visualization to the midportion of the calcarine arteries are noted bilaterally (arrowheads) and were judged PCA pruning, grade 2. Follow-up MR imaging and MRA (not shown) obtained 1 month after toxicity demonstrated complete resolution of the vasogenic edema in the occipital poles with marked improvement in distal PCA flow bilaterally along with reversal of the pruning and vasospasm.

Patient 33 is a 23-year-old pregnant woman with baseline blood pressure of 125/75 mm Hg who developed eclampsia. Blood pressure at toxicity was 200/103 mm Hg. A, Axial MR imaging (FLAIR sequence) demonstrates vasogenic edema consistent with PRES in the parietal lobes bilaterally (curved arrows) and was judged edema, grade 1. Vasogenic edema consistent with PRES was also present in the frontal lobes, occipital region, and cerebellum (not shown). B, Collapsed view of the 3D TOF MRA sequence demonstrates PCA spasms bilaterally without PCA foreshortening (arrows) and was judged PCA pruning, grade 1. The ACA spasm present is also partially visible on this collapsed view (arrowheads).