Cerebral infarction is an extremely rare postoperative complication of anterior cervical discectomy and fusion (ACDF), particularly in the delayed setting. We present a case who had a sudden stroke on day 18 after surgery. By sharing our experience with this case, we hope to provide new information about stroke after anterior cervical surgery.

We present the case of a 61-year-old man with more than 20 years of hypertension and 14 years of coronary heart disease who had suffered a stroke 11 years ago. The patient was admitted for a multiple ACDF due to symptoms of cervical spondylotic myelopathy and had a sudden stroke on day 18 after surgery. Imaging findings showed a large-area infarct of his left cerebral hemisphere and thrombosis in his left common carotid artery. With the consent of his family, the thrombus was removed and a vascular stent was implanted through an interventional operation. Forty days later, the patient was transferred to a rehabilitation hospital for further treatment. He had normal consciousness but slurred speech at the 1-year follow-up evaluation. The motor and sensory functions of his hemiplegic limbs partially recovered.

This case illustrated that a postoperative stroke related to anterior cervical surgery may be attributed to prolonged carotid retraction and might have a long silent period. Preventive measures include careful preoperative and postoperative examination for high-risk patients as well as gentle and intermittent retraction of carotid artery sheath during operation.

Anterior cervical discectomy and fusion (ACDF) is an important surgical option in the treatment of cervical degenerative disease, which has a good clinical efficacy and safety with a low incidence of complications[1]. However, since the anterior cervical approach requires intraoperative retraction of carotid artery sheath to expose adequate surgical field, it may affect the hemodynamics of carotid artery and even cause some serious complications in atherosclerotics[2]. In fact, the references from the academic search were limited and insufficient to explain the incidence and timing of cerebral infarction after ACDF. There are only three previous case reports on postoperative cerebral infarction related to cervical spine surgery. Two reports showed cases of stroke occurring immediately after surgery, and the remaining one reported the occurrence at postoperative day 3[3-5]. There has been no report about delayed cerebral infarction occurring after the whole perioperative period of an ACDF.

Herein, we report a case who had a sudden stroke on day 18 after a multilevel ACDF. To the best of our knowledge, this is the first case of massive brain infarction reported after a whole perioperative period. We remind surgeons of this causal relationship segmented by time intervals, discuss the etiology of this rare entity, and report notes on the management.

Based on the above findings, a diagnosis of common carotid artery thrombosis and a new left hemispheric infarct after cervical spine surgery was established.

With the consent of his family, the thrombus was removed and a vascular stent was implanted with an emergency interventional operation.

Forty days later, the patient was transferred to a rehabilitation hospital for further treatment and exercise. He had normal consciousness but slurred speech at the 1-year follow-up evaluation. The motor and sensory functions of his hemiplegic limbs were partially restored.

We present a case of massive cerebral infarction that occurred 18 d after a multilevel ACDF. It is clear that he had several risk factors for cerebral infarction, including atherosclerotic lesion in the carotid artery, hypertension, coronary heart disease, and previous stroke history[6-9]. On the basis of these factors, discontinuation of aspirin, surgical stress, acute dehydration, and blood pressure fluctuation might collectively precipitate the carotid thrombosis[10,11]. According to the Essen-Stroke-Risk-Score (ESRS) system, the patient should be quantified as median risk (7/9) based on his preoperative status[8,12].

Theoretically, prolonged retraction of the atherosclerotic carotid artery would influence the stability of plaques or even damage the fibrous caps of atheromas, which eventually brought about serious cerebrovascular accidents[13-15]. This is an obvious defect of a long-standing anterior cervical spine surgery. Retraction could also cause changes in carotid artery hemodynamics by reducing cross-sectional area of local vessels but increasing turbulent blood flow[2]. Coupled with perioperative hypercoagulability, all three factors of Virchow were present on one patient and caused the carotid thrombosis[16]. Therefore, we thought that gentle manipulation and intermittent relaxation of retraction should be given in surgery to avoid excessive mechanical stimulation on vessels.

According to the search results of Google Scholar, only three case reports of acute cerebral infarction following cervical spine surgery have been published[3-5]. Afana et al[3] deemed that intraoperative surgical manipulation, hypotensive anesthesia, and prolonged neck hyperextension might contribute to their patients’ stroke. Graffeo et al[5] expressed similar sentiments and speculated that the true incidence of cerebral ischemia might be underestimated by current reports, particularly in the delayed setting. Perhaps that was the fact - to the best of our knowledge, this is the first report of cerebral infarction occurring 2 wk after a cervical spine surgery.

It cannot be concluded with certainty that the cerebral infarction was due to mechanical stimulation during the operation, but available evidence tended to prove the point. The angiographic images showed that the thrombus was at the initial segment of the patient’s left common carotid artery, which was exactly the site of intraoperative retraction. It was not the common multiple lacunar infarcts that caused the stroke in this patient but a massive infarct of the left hemisphere. In addition, the case illustrated that a stroke related to anterior cervical spine surgery might have a long silent period during which a carotid thrombus had formed. Patients were at high risk of strokes with few symptoms in this stage and blood pressure fluctuation might play the role of trigger. Besides, the rise of blood pressure could also lead to hemorrhagic strokes with severe symptoms equally[17].

Several studies have shown that aspirin should not be suspended before surgery in patients who have been taking aspirin for a long time, because aspirin has no significant effect on intraoperative and postoperative bleeding[18,19]. Perioperative discontinuation of aspirin may affect coagulation status, thereby increasing the incidence of cardiovascular and cerebrovascular accidents, especially in patients with previous coronary heart diseases or strokes[20]. Perioperative use of anticoagulants such as low molecular weight heparin may also be useful in preventing serious complications[21]. In addition, lipid-lowering drugs can stabilize atheromatous plaques and limit the formation and expansion of thrombosis[22,23]. Preoperative coagulation tests are valuable in evaluating the coagulation status of patients.

Adequate preoperative risk assessment and examination can help identify risk factors for stroke and screen out patients with atherosclerosis. Carotid, transcranial, and cardiac Doppler ultrasound should be performed in high-risk patients before cervical spine surgery to assess the condition of their vessels and the possibility of stroke[24]. If it is clear that there exists severe atherosclerosis unilaterally, an incision from the contralateral side or the feasibility of posterior approach should be considered.

The case has certain warning significance on the postoperative course. The use of antihypertensive agents, lipid-lowering drugs, and anticoagulants should be promptly resumed after surgery[7,21-23]. For patients with definite carotid atherosclerosis, carotid ultrasound can be repeated after surgery to determine the presence of thrombus. For high-risk patients with dizziness, headache, or nausea after surgery, relevant examinations should be performed to exclude cerebral ischemia or infarction. Once it is clear that a patient has carotid thrombosis, aggressive interventions such as thrombectomy or thrombolytic therapy should be used to avoid the occurrence of subsequent stroke with poor clinical outcome[25,26].

This case illustrated that a postoperative stroke related to anterior cervical surgery may be attributed to prolonged carotid retraction and might have a long silent period during which a carotid thrombus had formed at the surgical site. Preventive measures include careful preoperative and postoperative examination for high-risk patients as well as gentle and intermittent retraction of carotid artery sheath during surgery.