PMC8769431_01
Imaging studies on the patients' arrival. (A) CT scan showing hyper-density of basilar artery tip (white arrowhead); however, the global ischemia of the posterior circulation is not evident. (B and C) On the MRI diffusion-weighted image, acute ischemic lesion was mainly located in the bilateral cerebellar hemisphere, and the bilateral thalamus and the brainstem were spared. (D) The occlusion of basilar artery tip was confirmed by time-of-flight MRA (white arrow). Comparison with the high intensity lesion in the diffusion-weighted image suggested that some ischemic penumbra remained.
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F1
On brain MRI, taken 360 min after symptom onset (80 min after his arrival), occlusion of the basilar artery tip was confirmed (Fig. 1). The retracted clot was 35 mm in length and had a red appearance (Supplementary Fig. 1A; All Supplementary figures are available online). Microscopically, the clot was composed largely of fibrin and red blood cells, and neutrocyte infiltration was also present; resembling a normal clot, the type usually found following mechanical thrombectomy (Supplementary Fig. 1B).
Infection control methods during mechanical thrombectomy. (A) To avoid the virus-containing droplets, the wall of the room was completely covered with disposable papers and vinyl. (B) To minimize contamination, all movements of medical staff and patients were controlled under the zoning concept (Dr.: doctor, RT: radiologic technician). Drs. 1 and 2 (operator and main assistant, respectively) completed sterilization procedure and remained in the dirty zone during the procedure. Dr. 3 (anesthesiologist) also stayed in the room. The radiation technician stayed mainly in the dirty zone, but if necessary, entered the boundary zone to provide Dr. 4 (who remained in the clean zone) with (the minimally required) devices and medicines. (C) All medical staff in the contaminated environment used maximal barrier protection, including N95 mask and face-shield. (D) The schema summarizing the time course of the case. The patient was transferred to our hospital 280 min after symptom onset. The overall time from symptom onset to recanalization was 516 min.
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F2
To avoid contamination from virus-containing droplets, the wall of the room was completely covered with disposable papers and vinyl (Fig. 2A). To minimize contamination, all movements of the medical staff and patients were controlled under the zoning concept (Fig. 2B). All the medical staff in the contaminated environment protected themselves with maximal barrier protection, including N95 masks and face shields (Fig. 2C). All preparations were performed while the patient was intubated in the emergency room (Fig. 2D). Alameda, CA, USA), but only tiny clots were retrieved and recanalization was not successful. In the third pass, the combination of a stent retriever (Solitaire Platinum 4 x 20 mm; Medtronic, Minneapolis, MN, USA) and ACE60 (Penumbra Inc.) (Fig. 2B) was used during the recanalization of the basilar tip, but the distal occlusion of the right posterior cerebral artery and the left superior cerebellar artery remained. After the unsuccessful fourth attempt of recanalizing the right posterior cerebral artery with ACE60 ADAPT, we stopped the procedure.
Mechanical thrombectomy. (A and B) Left vertebral angiogram (A: anteroposterior [AP] view, B: lateral view) after guiding catheter navigation revealed basilar tip occlusion. (C and D) In the third pass, a combination of a stent retriever (Solitaire Platinum 4 x 20 mm) (white arrow) and an aspiration catheter ACE60 (white arrowhead) lead to the recanalization of basilar tip (C: AP view, D: lateral view). (E and F) After a total of four passes, TICI 2b recanalization was achieved (E: AP view, F: lateral view). Onset to recanalization time was 516 min (puncture to recanalization time was 58 min). Note the residual occlusion of right PCA (black arrow) and left SCA (black arrowhead).
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F3
Left vertebral angiogram revealed basilar tip occlusion (Fig. 3A). TICI 2b and the onset to recanalization time was 516 min (puncture to recanalization time was 58 min) (Fig. 3C). The postoperative CT scan showed slight subarachnoid hemorrhage at the left ambient cistern, but intracranial hemorrhage was not observed.
Follow-up images of CT scans over time. Because cerebellar edema and hydrocephalus were observed on follow-up CT scans, a decompressive craniectomy was performed 18 h after arrival.
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F4
As cerebellar edema and hydrocephalus were observed on follow-up CT scans, a decompressive craniectomy was performed 18 h after arrival (Fig. 4).