Posterior Circulation Hyperperfusion Syndrome after Bilateral Vertebral Artery Intracranial Stenting

Suspected Cerebral Hyperperfusion Syndrome after Stenting for Intracranial Vertebral Artery Stenosis Associated with Reduced Cerebral Blood Flow to the Posterior Cerebral Artery Territory

Objective

Although several studies have reported on cerebral hyperperfusion syndrome (CHS)/hyperperfusion phenomenon (HPP) involving the anterior circulation after carotid artery stenting (CAS), little is known about CHS/HPP involving the posterior circulation after percutaneous transluminal angioplasty (PTA) and stenting of the vertebral artery (VA).

Case Presentation

A 79-year-old man with known chronic occlusion of the left VA (V4 segment) was admitted to another hospital with right-sided hemiplegia, mild disturbance of consciousness, and dysphagia. A head MRI revealed multiple infarcts in posterior circulation areas, and severe stenosis of the right VA (V4 segment). Single photon emission computed tomography (SPECT) indicated reduced cerebral blood flow (CBF) in the posterior circulation, and DSA revealed 76% stenosis of the right V4 segment. On day 18, PTA/stenting was performed under general anesthesia for the severe stenosis of the right VA. However, head MRI and CT on postoperative day (POD)1 showed intracranial hemorrhage (ICH) occupying an area measuring 2 cm in diameter in the left posterior lobe and a small subdural hematoma (SDH). SPECT on POD1 indicated increased CBF in the posterior lobe, and we diagnosed CHS might have caused ICH. Although SPECT on POD4 showed residual hyperperfusion, SPECT on POD11 revealed reduced CBF in the posterior circulation area.

Conclusion

Our patient developed ICH after undergoing PTA/stenting for known severe symptomatic stenosis of the right VA. CHS/HPP in the posterior cerebral artery territory might be one of the etiologies, and reduced CBF prior to the procedure could be a risk factor for CHS/HPP developing after PTA/stenting.

Utility of Near-infrared Spectroscopy Monitoring in the Management of Hyperperfusion Syndrome after Intracranial Carotid Artery Stenting

Cerebral hyperperfusion syndrome (HPS) is a rare complication of carotid endarterectomy (CEA) and stenting. There are only a few case reports about HPS after intracranial stenting, and its clinical course remains unclear. We report an unusual case of HPS after intracranial internal carotid artery (ICA) stenting. An 87-year-old woman underwent uneventful balloon angioplasty for the right intracranial ICA one year ago; then she presented with restenosis at the same arterial location. She then underwent an ICA stent placement procedure. Preoperative cerebral blood flow (CBF) studies revealed hemodynamic ischemia. At the time of surgery, the stenotic lesion was near-occlusion. Twelve hours after the successful stenting procedure, the patient became restless, and near-infrared spectroscopy (NIRS) indicated a blood flow increase to the affected side. Arterial spin labeling (ASL) imaging performed on the same day showed high signal intensity only in the right hemisphere. She was treated with sedation, blood pressure control, and minocycline hydrochloride administration. Because of the strict management under continuous monitoring with NIRS, her symptoms gradually improved over the next 6 days. The right-to-left difference observed with ASL imaging resolved 6 days after surgery, and she was discharged with no neurological deficit. This case highlights the utility of NIRS monitoring in the management of HPS after intracranial stenting.

Endovascular Recanalization of Nonacute Symptomatic Vertebral Ostial Occlusion Performed Using a Distal Embolic Protection Device

OBJECTIVE

Endovascular recanalization of symptomatic vertebral ostial occlusion in the nonacute phase has not been well documented. Distal thromboembolic events negatively affect the success of endovascular treatment. We aimed to investigate the feasibility, safety, and outcomes of stenting performed with the use of a distal embolic protection device for patients with symptomatic vertebral ostial occlusion in the nonacute phase.

METHODS

We retrospectively reviewed the data of 7 patients with symptomatic vertebral ostial occlusion despite medical management who underwent stenting performed using a distal embolic protection device between January 2015 and February 2019. The occlusive lesions were predilated with small balloons, followed by placement of distal embolic protection devices and stents sequentially. At last, the protection devices were retrieved. The rate of successful recanalization, perioperative complications, and clinical and angiographic outcomes were analyzed.

RESULTS

The rate of successful recanalization was 100% with all distal embolic protection devices deployed and retrieved. Poststenting angiography showed no significant residual stenosis. There were no major acute thromboembolic events during and after the procedure. There were no recurrent ischemic symptoms after a mean clinical follow-up of 20.6 ± 16.3 months. At 6-month imaging follow-up, repeat vascular images from 5 patients showed asymptomatic restenosis in 1 artery.

CONCLUSIONS

Our single-center preliminary experience indicated that performing stent placement for vertebral ostial occlusion using a distal protection device may be feasible with a high rate of procedural success. However, this strategy should be confirmed in future prospective randomized studies with larger patient numbers.

Cortical blindness as a rare presentation of hemorrhagic cerebral hyperperfusion syndrome following vertebral angioplasty

Cerebral hyperperfusion syndrome (CHS) is a well-documented complication after carotid endarterectomy or stenting. In contrast, CHS following vertebral revascularization is extremely rare. Here we present a case of a 77-year-old man with high-grade vertebral stenosis who subsequently underwent balloon angioplasty, complicated by hemorrhagic CHS manifesting as cortical blindness, although strict postoperative blood pressure control was administered. To our knowledge, cortical blindness as a presentation of hemorrhagic CHS has not previously been reported. This study highlights the fact that identifying high-risk patients, as well as making an individual therapeutic plan, is important prior to revascularization. Further studies are needed to elucidate the exact mechanism of this condition and thereby prevent it.

Cortical blindness as a rare presentation of hemorrhagic cerebral hyperperfusion syndrome following vertebral angioplasty

Cerebral hyperperfusion syndrome (CHS) is a well-documented complication after carotid endarterectomy or stenting. In contrast, CHS following vertebral revascularization is extremely rare. Here we present a case of a 77-year-old man with high-grade vertebral stenosis who subsequently underwent balloon angioplasty, complicated by hemorrhagic CHS manifesting as cortical blindness, although strict postoperative blood pressure control was administered. To our knowledge, cortical blindness as a presentation of hemorrhagic CHS has not previously been reported. This study highlights the fact that identifying high-risk patients, as well as making an individual therapeutic plan, is important prior to revascularization. Further studies are needed to elucidate the exact mechanism of this condition and thereby prevent it.

Cerebral hyperperfusion syndrome after intracranial stenting of the middle cerebral artery

Cerebral hyperperfusion syndrome (CHS) is a rare complication following cerebral revascularization. It presents with ipsilateral headache, seizures, and intracerebral hemorrhage. It has mostly been described following extracranial carotid endarterectomy and stenting and it is very unusual after intracranial stenting. A 71-year-old man with a stuttering stroke was taken up for a cerebral angiogram (digital subtraction angiography), which showed a dissection of the distal left middle cerebral artery. This was recanalized with a solitaire AB stent. After 12 h, the patient developed a right hemiplegia and aphasia. Computed tomography brain showed two discrete intracerebral hematomas in the left hemisphere. This is the first reported case of CHS following intracranial stenting from India.