PMC4258721_01
(a) Cerebral blood volume scan from a CT perfusion study obtained at the time of admission. A small area of volume deficit is visible in the left PCA territory. (b) Time-to-peak map from the CT perfusion study showing a large area of reduced perfusion in the left PCA, consistent with salvageable penumbra. (c) CT angiogram of the common carotid artery. Proximal occlusion consistent with a dissection flap is seen (arrow). (d) CT angiogram of cerebral vessels showing an early filling defect in the terminal ICA (arrow)
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Computed tomography (CT) perfusion imaging suggested a large posterior cerebral artery (PCA) distribution, salvageable penumbra [Figure 1a]. CT angiography (CTA) revealed left internal carotid artery (ICA) occlusion extending from the carotid bulb up to the terminus with a luminal defect suspicious for a thrombus [Figure 1b]. 4D CTA reconstructions revealed delayed filling of the left anterior cerebral artery and middle cerebral artery (MCA) through the anterior communicating artery (ACOM), but there was no filling of the ICA terminus [Figure 1c and d].
Angiograms preceding and following endovascular intervention. (a) Right ICA injection showing contralateral filling of the MCA with a defect suggestive of a dissection in the ICA terminus on the left (arrow). (b) Left vertebral injection showing filling of the right but not the left PCA. There is retrograde filling of the distal left P2 by superior cerebellar artery collaterals (arrow on far right). (c) Left carotid artery angiogram showing progressive narrowing of the ICA lumen (arrow), consistent with artery dissection. (d) Left ICA injection showing late filling of the left ophthalmic artery due to collateral circulation (arrow). No back filling of the ICA terminus was observed. (e) Left ICA injection is shown. The Penumbra catheter (Penumbra, Inc., Alameda, California, USA) visibly cleared the proximal ICA occlusion; however, a dissection flap is visible distally (arrow). (f) Angiogram obtained immediately after Solitaire (ev3-Covidien, Irvine, California, USA) thrombectomy shows good filling of the distal ICA; however, an occlusion persists in the left P2 segment of the PCA (arrow)
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This suggested the presence of a dissection in the left ICA with an embolus in the ophthalmic, communicating, and terminal segments of the ICA [Figure 2a-d]. Aspiration catheter (Penumbra Inc., Alameda, California, USA) resulted in recanalization of the entire ICA with persistent fetal PCA occlusion [Figure 2e]. A 4 x 15 mm Solitaire stentriever (ev3-Covidien, Irvine, California, USA) was then deployed in the left PCA up to the P2 segments, and thrombectomy was performed. The vessel recanalized with residual occlusion beyond the P3 segment [Figure 2f].
Picture taken on hospital day 4 of patient's right and left eyes, respectively. Mydriasis of the left eye is visible with deviation laterally and inferiorly
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During the 8 h after the thrombectomy procedure, the patient developed a progressive left mydriatic pupil, which ultimately became fixed at 7 mm in diameter to light stimulation [Figure 3].
(a) CT scan of the head on hospital day 1, after left pupillary dilation was first observed. Hypodensity in the left PCA territory is seen; no effacement of cisterns was evident. (b) Axial T2 fluid-attenuated inversion recovery (FLAIR) magnetic resonance image on hospital day 5 showing evolving left PCA infarct. (c) Coronal T2 magnetic resonance image of head. A left-sided hyperintensity is visible in the retroglobar area (arrow), consistent with congestion of the superior ophthalmic vein
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A repeat head CT scan did not show any significant effacement of the basal cisterns [Figure 4a]. Magnetic resonance imaging revealed infarction of the distal PCA territory with sparing of the midbrain and multiple embolic infarcts of the MCA territory [Figure 4b and c].