Correspondence: Microsurgical thrombectomy: Where the ancient art meets the new era

Surgical thrombectomy remains a feasible technique in an accurately selected patient population with large vessel occlusion, even though endovascular mechanical thrombectomy is the gold standard. It especially warrants consideration in cases where the endovascular approach is unfeasible or fails. The current extension in the therapeutic window of time in mechanical thrombectomy also provides opportunities to open thrombectomy. To support our view, we present a case of a patient who suffered an ischemic stroke. Intravenous thrombolysis proved ineffective and mechanical thrombectomy was impossible due to extreme tortuosity of the internal carotid artery. Therefore, surgical thrombectomy was performed. The patient underwent successful recovery and states a great satisfaction. To improve efficiency and outcomes, a properly organised and trained surgical team with plentiful neurovascular experience is necessary. Finally, open thrombectomy is the most effective approach to completely restore luminal patency compared to the endovascular approaches yet risks due to the operation should be taken into account.

2-1-2 Stroke microsurgical thrombectomy technique as a tertiary/salvage treatment option

BACKGROUND

Microsurgical thrombectomy (MST) has been used for many years in few stroke cases without any prospective randomized study, nor detailed systemized technique description. As many centers worldwide are recruited for stroke thrombectomy availability, MST might increase in the near future either as a tertiary or salvage treatment option. A straightforward surgical plan is mandatory empowering a safe, efficient, and rapid neurosurgical operation, so our aim is to describe the 2-1-2 microsurgical technique.

METHODS

Three patients presented at emergency department with large stroke not suitable to venous thrombolysis and/or mechanical thrombectomy due to late arrival time and endovascular suite technical problems. They were referred to 2-1-2 MST after imaging showed brain collaterals on head angio-CT scan and ASPECTS greater than 6 points. The procedure comprised 2 insulin needle punctures in the target artery, 1mm micro-scissor transverse arteriotomy, milk thrombus removal and 2 simple sutures micro stitches. Sixty days clinical follow-up and brain imaging control provided data results.

RESULTS

All patients treated with 2-1-2 MST technique had complete thrombus removal by precise surgical maneuvers avoiding surgeons unplanned and insecure movements to reduced operation time. Head angio-CT scan evidenced complete cerebrovascular circulation re-flow with clinical improvements in 60 days follow-up without complications or hospital readmissions.

CONCLUSIONS

2-1-2 MST technique can be rapidly and efficaciously performed in a systemized manner offering a tertiary or salvage technique for acute stroke treatment. Specific microsurgical training is mandatory to accomplish this treatment and larger studies are necessary to confirm our hypothesis.

Emergent microsurgical intervention for acute stroke after mechanical thrombectomy failure: a prospective study

Background

Despite all the gains that have been achieved with endovascular mechanical thrombectomy revascularization and intravenous thrombolysis logistics since 2015, there is still a subgroup of patients with salvageable brain tissue for whom persistent emergent large vessel occlusion portends a catastrophic outcome.

Objective

To test the safety and efficacy of emergent microsurgical intervention in patients with acute ischemic stroke and symptomatic middle cerebral artery occlusion after failure of mechanical thrombectomy.

Methods

A prospective two-center cohort study was conducted. Patients with acute ischemic stroke and middle cerebral artery occlusion for whom recanalization failed at center 1 were randomly allocated to the microsurgical intervention group (MSIG) or control group 1 (CG1). All similar patients at center 2 were included in the control group 2 (CG2) with no surgical intervention. Microsurgical embolectomy and/or extracranial–intracranial bypass was performed in all MSIG patients at center 1.

Results

A total of 47 patients were enrolled in the study: 22 at center 1 (12 allocated to the MSIG and 10 to the CG1) and 25 patients at center 2 (CG2). MSIG group patients showed a better clinical outcome on day 90 after the stroke, where a modified Rankin Scale score of 0–2 was reached in 7 (58.3%) of 12 patients compared with 1/10 (10.0%) patients in the CG1 and 3/12 (12.0%) in the CG2.

Conclusions

This study demonstrated the potential for existing microsurgical techniques to provide good outcomes in 58% of microsurgically treated patients as a third-tier option.

Open Microvascular Thrombectomy for Acute Intracranial Large Vessel Occlusion: Microsurgery in the Endovascular Thrombectomy Era

BACKGROUND

Open microsurgical thrombectomy for acute intracranial large vessel occlusion (LVO) has been the subject of dozens of case reports and series. However, no clear indications exist to define its role in the management of acute ischemic stroke. Our aim was to review all the available data on open microsurgical thrombectomy, for both spontaneous as well as iatrogenic intracranial vessel occlusion, in terms of indication and results.

METHODS

Of the 390 articles screened, 33 were included after full text screening.

RESULTS

A total of 232 patients were reported, of whom 208 received microsurgical thrombectomy and 24 received bypass for large vessel occlusion. Patients were divided into a historic cohort (before 2002) and a recent cohort (articles published after 2002). Patients from the historic cohort were younger: median age, 55 years (interquartile range, 34-57 years) versus 69 years (interquartile range, 63-75 years) in the recent cohort (P < 0.01). The procedure was successful more often in the recent cohort (65% of patients in the historic cohort vs. 98% of patients in the recent cohort) and more patients experienced neurologic improvement (56% of patients in the historic cohort vs. 69% in the recent cohort).

CONCLUSIONS

In the era of endovascular thrombectomy, open microsurgical techniques might still play a role in highly selected patients. The reported patients show that microsurgical thrombectomy seems efficient and effective in improving patient outcome. Ideally, a multidisciplinary approach with vascular neurosurgeons trained and skilled in microvascular techniques is recommended.

Re-endovascular recanalization for acute middle cerebral artery reocclusion after surgical embolectomy

A 62-year-old woman with atrial fibrillation underwent burr hole trephination for a chronic subdural hematoma. Two days later the patient suddenly presented with motor dysphasia and slightly decreased motor power. Time of flight MR angiography revealed distal M1 occlusion without diffusion restriction. Stent-assisted mechanical thrombectomy was attempted but failed. Post-procedure MRI illustrated a small area of diffusion restriction within the peri-insular and parietal areas. Immediate surgical embolectomy was performed but reocclusion of M1 was documented in the postoperative angiography. Stent-assisted revascularization with a Solitaire stent was conducted and immediate restoration of blood flow was observed. The patient's motor weakness and motor dysphasia recovered fully. Re-endovascular intervention can be beneficial in selected patients for acute middle cerebral artery reocclusion after surgical embolectomy when endovascular thrombectomy fails.

Re-endovascular recanalization for acute middle cerebral artery reocclusion after surgical embolectomy

A 62-year-old woman with atrial fibrillation underwent burr hole trephination for a chronic subdural hematoma. Two days later the patient suddenly presented with motor dysphasia and slightly decreased motor power. Time of flight MR angiography revealed distal M1 occlusion without diffusion restriction. Stent-assisted mechanical thrombectomy was attempted but failed. Post-procedure MRI illustrated a small area of diffusion restriction within the peri-insular and parietal areas. Immediate surgical embolectomy was performed but reocclusion of M1 was documented in the postoperative angiography. Stent-assisted revascularization with a Solitaire stent was conducted and immediate restoration of blood flow was observed. The patient's motor weakness and motor dysphasia recovered fully. Re-endovascular intervention can be beneficial in selected patients for acute middle cerebral artery reocclusion after surgical embolectomy when endovascular thrombectomy fails.

The site of embolization related to infarct size, oedema and clinical outcome in a rat stroke model - further translational stroke research

Background and purpose

Reliable models are essential for translational stroke research to study the pathophysiology of ischaemic stroke in an effort to find therapies that may ultimately reduce oedema, infarction and mortality in the clinic. The purpose of this study was to investigate the relation between the site of arterial embolization and the subsequent oedema, infarction and clinical outcome in a rat embolic stroke model.

Methods

Thirty-six male Sprague-Dawley rats were thromboembolized into the internal carotid artery. The site of occlusion was demonstrated by arteriography. Following histological preparation and evaluation, the size of the hemispheres and the infarcts were measured by quantitative histology and planimetry. Another parallel stroke model study was subsequently examined to investigate if the conclusions from the first study could be applied to the second study.

Results

The median size of the infarct was 40% of the ipsilateral hemisphere in both the 19 animals with occlusion localised to the intracranial part of the internal carotid artery and in the 11 animals where the main trunk of the middle cerebral artery was occluded. In 5 animals, occlusion of the extracranial part of the internal carotid artery resulted in significantly smaller infarcts compared to other groups (p < 0.01). Another independent study re-confirmed these results. Furthermore, significant correlations (R > 0.76, p < 0.0001) were found between 1) cortical, subcortical, and total infarct volumes, 2) oedema in percent of the left hemisphere, 3) clinical score before termination and 4) postoperative weight loss.

Conclusions

Distal occlusions of the intracranial part of the internal carotid or middle cerebral arteries resulted in comparable large sized infarctions and oedema. This indicates that investigators do not need a similar number of such occlusions in each experimental group. Contrary to observations in the clinic, distal internal carotid artery occlusions did not result in worse outcome than middle cerebral stem occlusions, but this finding may be explained by the controlled emboli size in this experimental stroke model.

Emergency embolectomy for embolic occlusion of the middle cerebral artery-review of the literature and two illustrative cases

With the increasing number of endovascular interventions during the last years, the number of procedure-related complications has risen accordingly. Despite sophisticated and effective endovascular treatments for acute thromboembolic events during intervention, vessel occlusion can remain refractory to medical and endovascular treatment. In case of failure of the endovascular revascularisation, microsurgical embolectomy in the anterior circulation can be a last therapeutic option, if case selection is adequate. To date, this rather aggressive form of treatment is still controversial, and there are only few series of reported surgical embolectomy. In the present review, we conducted a Medline (www.pubmed.org) search for reports or studies of microsurgical embolectomies using the keywords (1) middle cerebral artery (MCA) occlusion and (2) embolectomy. The most relevant factors for positive outcome were concluded as such: (1) vessel occlusion time, (2) collateral flow, (3) occlusion site and (4) thromboembolic origin. Additionally, we report on two illustrative cases from our department with acute MCA occlusion treated by emergency microsurgical embolectomy but with very contrary outcomes. Hence, emergency embolectomy in patients with MCA occlusion following endovascular treatment can be quite effective, if endovascular recanalisation options fail. Nevertheless, the decision-making process must be made critically, fast and based on factors such as vessel occlusion time, sufficient collateral flow, occlusion site and thrombus origin.