PMC8769471_01
(A-C) Image findings on admission at the previous hospital. (D-I) Image findings 4 days after the mitral valve repair. (A) CT image showing no abnormal findings. (B) MR angiography image showing almost normal findings. (C) Axial magnetic resonance (MR) diffusion-weighted image showing subtle acute ischemic change involving the left middle cerebral artery (MCA) territory. (D) CT image showing a low-density lesion (arrow) within the right MCA. The density value was approximately -40 to -20 Hounsfield units. (E) MR angiography image showing stenosis of the M2 of the right MCA (arrow). (F) Axial MR diffusion-weighted image showing new ischemic change involving the right MCA territory. (G) T1-weighted MR image showing arterial lumen narrowing at the stenotic lesion (arrow). (H, I) T2-weighted (H) and T2-star (I) MR images showing that the stenotic lesion was markedly hypo-intense (arrow).
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Computed tomography (CT) scans confirmed no abnormal findings (Fig. 1A). MR angiography findings were almost normal (Fig. 1B), and diffusion-weighted imaging revealed subtle acute ischemic change in the left MCA territory (Fig. 1C). MCA, with a density value of approximately -40 to -20 Hounsfield units (Fig. 1D). MR angiography revealed stenosis of the M2 of the right MCA (Fig. 1E), which corresponded to the low-density area on CT findings. Diffusion-weighted imaging also revealed new ischemic change in the right MCA territory (Fig. 1F). T1-weighted MR images (Fig. 1G) demonstrated arterial lumen narrowing at the stenotic lesion. T2-weighted (Fig. 1H) and T2-star (Fig. 1I) MR images showed that the stenotic lesion was markedly hypo-intense.
(A) Angiographic images of the right internal carotid artery, anteroposterior view, showed the proximal M2 superior trunk stenosis of the right middle cerebral artery (MCA) (arrow) with maintaining peripheral blood flow. (B) 3D reconstruction from angiography revealed 62% irregular stenosis at the superior M2 of the right MCA (arrow). (C) 123 I-IMP-single photon emission CT revealed moderate perfusion defect in the right MCA territory, which was a 12% decrease compared with contralateral side.
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Angiography demonstrated 62% irregular stenosis at the superior M2 of the right MCA with antegrade peripheral blood flow (Fig. 2A and 2B). However, despite conservative therapy, transient mild-to-moderate left hemiplegia appeared every few days during physical therapy for walking, and the resting 123 I-IMP-single photon emission CT revealed moderate perfusion defect in the right MCA territory, which was a 12% decrease compared with contralateral side (Fig. 2C).
Intraoperative view of the right superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. (A) The STA frontal and parietal branches were anastomosed to the M4 of the right MCA (arrows), which supplied the distal stenotic lesion. (B) Indocyanine green video-angiography confirming the patency of the bypass graft (arrows).
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Nineteen days after the initial transient ischemic attack, we anastomosed right STA frontal and parietal branches to the M4 of the right MCA, which supplied the distal segment of the M2 stenotic lesion (Fig. 3A). Indocyanine green video-angiography confirmed the patency of the bypass graft (Fig. 3B).
(A-D) Image findings after the superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. (E, F) Last follow-up image findings 18 months after STA-MCA anastomosis. (A) CT image showing a very low-density area in the MCA (arrow), which did not change compared with preoperative findings. (B) MR angiography image confirming patency in the STA-MCA anastomosis (arrowheads) and showing no change in the stenotic lesion at the M2 of the right MCA (arrow). (C, D) T1-weighted (C) and T2-weighted (D) magnetic resonance images showing no change in the stenotic lesion compared with preoperative findings (arrow). (E) CT image showing that the very low-density stenotic lesion within the MCA (arrow) is unchanged. (F) MR angiography image showing no change in the stenotic lesion at the M2 of the right MCA (arrow).
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MCA, which did not change compared with preoperative findings (Fig. 4A). MR angiography confirmed the patency of the STA-MCA anastomosis (Fig. 4B). T2-weighted (Fig. 4D) MR images also confirmed that the stenotic lesion was unchanged. The patient was discharged with a modified Rankin scale score of 1, and he did not suffer neurological deterioration during the follow-up period. The latest follow-up CT (Fig. 4E) and MR angiography (Fig. 4F) 18 months after surgery showed that the stenotic lesion was unchanged.