Intracranial mechanical thrombectomy without extracranial revascularization for a tandem occlusion with robust Circle of Willis: Case report

•Tandem occlusions of the internal carotid artery are challenging to treat.•There is debate on whether the intracranial occlusion or the extracranial occlusion should be addressed first.•There is also debate on the appropriate technique/modality that should be used for each type of occlusion.•We present a select case with a good clinical outcome due to robust collateral circulation via the Circle of Willis. A 59-year-old male presented with a severe left middle cerebral artery (MCA) syndrome, a National Institutes of Health Stroke Scale (NIHSS) of 17, and was last known well 26 h prior. Computed tomography angiography (CTA) of the head demonstrated a tandem extracranial ICA and intracranial ICA/MCA occlusion. Computed tomography perfusion (CTP) demonstrated a large mismatch. The patient underwent a mechanical thrombectomy using a stent retriever resulting in a modified thrombolysis in cerebral infarction (mTICI) score of 2b. A balloon angioplasty of the extracranial carotid occlusion only resulted in temporary restoration of flow so stent placement was considered. Prior to stent placement, however, cerebral angiography revealed good collateral supply to the left MCA territory via the Circle of Willis. The procedure was thus terminated given good collateral supply from the right side and the unknown risk of dual antiplatelet therapy in a patient with an unknown stroke burden. Postoperatively, the patient immediately improved and magnetic resonance imaging (MRI) of the brain revealed minimal stroke burden. The patient was discharged to acute rehab with an NIHSS of 6. At 4 weeks, the patient’s NIHSS was 2 and his modified Rankin Scale (mRS) was 1. This case highlights important considerations, as well as one potential option, when treating tandem occlusions in patients with a robust Circle of Willis.