[Endovascular treatment of large and giant intracranial aneurysms using flow-diverting stents]

Small Unruptured Intracranial Aneurysms Can Be Effectively Treated With Flow-Diverting Devices

Purpose

To investigate the effect and safety of flow diverters in the management of small (<10 mm in diameter) unruptured intracranial aneurysms.

Materials and Methods

One hundred and ten patients with 145 small intracranial aneurysms treated with flow diverters were retrospectively enrolled. The clinical, endovascular, and follow-up data were analyzed.

Results

One hundred twenty-one flow diverters were deployed for the treatment of 145 small intracranial aneurysms in 110 patients, and the stenting success rate was 99.1%. In 133 (91.7%) aneurysms, only flow-diverting devices were deployed, and in the rest 12 (8.3%) of aneurysms, coils were used to loosely pack the aneurysm after deployment of a flow-diverting device. Five patients (4.5%) experienced ischemic complications, but no hemorrhagic complications were occurred. All patients had clinical follow-up 6-18 (median 12) after the procedure, with the modified Rankin scale score (mRS) 0 in 101 patients, 1 in four patients, 2 in three patients, 4 in one patient, and 5 in one patient. Digital subtraction angiography was performed at follow-up in 90 (81.8%) patients with 118 (81.4%) aneurysms 6-18 months (median 12) after the procedure, with the Raymond grade I in 90 (76.2%) aneurysms and Raymond grade III in 28 (23.7%). Eighteen patients with 22 partially occluded aneurysms at the first angiographic follow-up experienced the second digital subtraction angiography 12-36 months (median 26) after the procedure, and 21 (95.5%) aneurysms were completely occluded. Two patients had asymptomatic in-stent stenosis.

Conclusion

Treatment of small unruptured intracranial aneurysms with flow diverters can be performed safely and effectively with satisfactory outcomes.

Whether Intracranial Aneurysm Could Be Well Treated by Flow Diversion: A Comprehensive Meta-Analysis of Large-Sample Studies including Anterior and Posterior Circulation

BACKGROUND

Flow diversion (FD) has become a widely adopted treatment method for intracranial aneurysms in the clinic, but a comprehensive meta-analysis of large-sample studies including anterior and posterior circulation is still lacking.

METHODS

The PubMed, Embase, Web of Science, and Cochrane databases were searched between January 1, 2008, and December 1, 2019. A random-effect model was used to calculate the efficacy and safety data as well as 95% confidence intervals (CIs).

RESULTS

The pooled sample size of all included studies was 6695 patients; the mean age was 55.5 years old, with a total of 7406 aneurysms. For efficacy, the complete occlusion rate in angiographic follow-up (AFU) at 6 months was 78% (95% CI, 0.77, 0.80), and the AFU rate at 6-12 months was 90% (95% CI, 0.88, 0.92). For safety, the hemorrhagic event rate was 2%, the ischemic event rate was 5%, and the mortality rate was 3%.

CONCLUSION

FD is an effective and safe treatment for intracranial aneurysm with high complete occlusion rate and acceptable complication rate.

[Unruptured asymptomatic brain aneurysms: modern approaches to the choice of surgical method and treatment outcomes]

BACKGROUND

In recent years, significant attention has been paid to preventive vascular neurosurgery. Treatment of unruptured asymptomatic brain aneurysms is one of the sections of this surgery.

OBJECTIVE

To evaluate treatment outcomes in patients with unruptured asymptomatic brain aneurysms who underwent treatment chosen on the basis of criteria adopted at the Burdenko Neurosurgery Center.

MATERIAL AND METHODS

There were 2814 unruptured asymptomatic brain aneurysms in 2334 patients for the period from 1995 to 2019.

RESULTS

Microsurgical operations for unruptured asymptomatic brain aneurysms were performed in 64.9% of cases, endovascular procedures - in 35.1% of patients. Endovascular operations were usually performed for ICA aneurysms and posterior aneurysms of circle of Willis. Microsurgical operations were mainly performed in patients with aneurysms of anterior and middle cerebral arteries. Favorable outcomes (GOS grade V-IV) were obtained in most patients (98.3%). Incidence of severe complications was similar in both groups, mortality rate was 0.3% and 0.4%, respectively.

CONCLUSION

Currently, there is a tendency towards annual increase in the number of surgeries for unruptured brain aneurysms. Anatomical and morphological characteristics of aneurysm should be considered to achieve favorable clinical results. At the same time, comprehensive analysis of each case and identification of individual risk factors will eliminate serious complications of surgical treatment.

[Neurosurgery in Moscow: clinic - institute - ational center]

In 1929, a surgeon N.N. Burdenko and a neurologist V.V. Kramer founded the first neurosurgical clinic in Moscow, which was reorganized to the Institute of Neurosurgery in 1932. The Institute has come a long way through military and peaceful years, overcoming all sorts of obstacles. It has constantly developed, built, and modernized, and now this is the National Medical Research Center of Neurosurgery. In this article, we describe the history of the Institute/Center and its staff who have had a significant impact on the development of domestic and global neurosurgery.

Giant Serpentine Aneurysm of the Middle Cerebral Artery

BACKGROUND

Giant serpentine aneurysms (GSAs) are a subgroup of giant intracranial aneurysms, distinct from saccular and fusiform varieties, that are defined as partially thrombosed giant aneurysms with tortuous internal vascular channel. Clinicopathologic characteristics of middle cerebral artery GSAs have been rarely reported in the literature, with discussion of radiologic characteristics only. We clarify patient clinical and neuroradiologic features and discuss the mechanism of formation and progression.

CASE DESCRIPTION

A 43-year-old woman presented with a GSA arising from the middle cerebral artery. There was a separate inflow and outflow channel of the aneurysm, with the outflow channel feeding the distal branches of the parent artery and supplying normal brain parenchyma. The GSA was treated successfully by aneurysmectomy and superficial temporal artery-middle cerebral artery bypass followed by proximal occlusion and vascular reconstruction. An aneurysm specimen was examined to correlate pathologic findings and morphologic characteristics.

RESULT

Pathologic results showed that thickness of the aneurysmal wall was typically increased and varied, and no internal elastic lamina or endothelial lining could be identified. The sac contained thrombi of various ages with recanalizing vessel formation and chronic inflammation infiltration. Intimal hyperplasia and neoangiogenesis in the wall and hyaline degeneration of the media were observed. Vessels coursing in their adventitia showed mucoid changes, which are responsible for the contrast enhancement of the aneurysmal rim on computed tomography scan.

CONCLUSIONS

GSAs are a specific pathologic entity with unique morphologic and pathologic characteristics that can affect intracranial blood vessels. The pathogenic mechanisms are unclear; this report suggests that GSAs may be associated with degeneration of the vascular wall.

Temporary Stent-Assisted Coil Embolization as a Treatment Option for Wide-Neck Aneurysms

BACKGROUND AND PURPOSE

Simple coil embolization is often not a feasible treatment option in wide-neck aneurysms. Stent-assisted coil embolization helps stabilize the coils within the aneurysm. Permanent placement of a stent in an intracranial vessel, however, requires long-term platelet inhibition. Temporary stent-assisted coiling is an alternative technique for the treatment of wide-neck aneurysms. To date, only case reports and small case series have been published. Our purpose was to retrospectively analyze the effectiveness and safety of temporary stent-assisted coiling in a larger cohort.

MATERIALS AND METHODS

Research was performed for all patients who had undergone endovascular aneurysm treatment in our institution (University Hospital Aachen) between January 2010 and December 2015. During this period, 355 consecutive patients had undergone endovascular aneurysm treatment. We intended to treat 33 (9.2%) of them with temporary stent-assisted coiling, and they were included in this study. Incidental and acutely ruptured aneurysms were included.

RESULTS

Sufficient occlusion was achieved in 97.1% of the cases. In 94%, the stent could be fully recovered. Complications occurred in 5 patients (14.7%), whereas in only 1 case was the complication seen as specific to stent-assisted coiling.

CONCLUSIONS

Temporary stent-assisted coiling is an effective technique for the treatment of wide-neck aneurysms. Safety is comparable with that of stent-assisted coiling and coiling with balloon remodeling.

[The modern role of microsurgery in treatment of large and giant aneurysms of the internal carotid artery]

INTRODUCTION

Large (1.5-2.5 cm) and giant (>2.5 cm in diameter) aneurysms of the internal carotid artery (ICA) remain one of the complex neurosurgical pathologies in terms of microsurgery. In recent years, endovascular techniques for treatment of paraclinoid aneurysms, in particular ICA reconstruction using flow-diverting stents, have become a priority. However, surgery of flow stents has a number of limitations, therefore the choice of treatment in each case is individual.

PURPOSE

To analyze the results of direct surgery in patients with large and giant aneurysms of the ICA and to determine the role and place of modern microsurgical techniques in the treatment of this vascular disease.

MATERIAL AND METHODS

The study included 260 patients with large and giant ICA aneurysms who were operated on at the Institute using microsurgical techniques in the period between 2001 and 2015. The mean age of patients was 45.1 years. The male/female ratio was 1:2.5. One hundred sixty four (63.1%) patients were operated on after hemorrhages, of whom 15 (5.7%) patients were operated on in the acute period; 69 (26.5%) patients had a pseudotumoral course of the disease; 9 (3.5%) patients had a mixed course of the disease; aneurysms were incidentally found in 18 (6.9%) patients. The aneurysm localization was as follows: paraclinoid aneurisms in 158 (60.7%) patients, supraclinoid aneurisms in 77 (29.6%) patients, and ICA bifurcation aneurisms in 25 (9.6%) patients. Microsurgical clipping was performed in 228 (87.7%) patients, including 158 (60.7%) patients in whom an intravascular blood aspiration technique was used. Aneurysm trapping using a flowmetry probe was performed in 16 patients, with creating vascular anastomoses in 4 (1.5%) cases. In 16 (6.2%) patients, interventions were completed by gauze strengthening. We performed a comparative analysis of the results of endovascular treatment of paraclinoid aneurysms reported in recent publications and obtained in the present series.

RESULTS

Treatment outcomes (Glasgow Outcome Scale) were favorable (Grade 4-5) in 224 (86.2%) patients and satisfactory in 29 (11.1%) patients. Two patients (0.7%) developed diencephalic (electrolyte) disturbances that were successfully corrected using replacement therapy. The mortality was 2.7% (7 patients); the treatment completeness was 94.3%. Comparison with the literature data demonstrated comparable results for both treatment techniques.

CONCLUSION

Microsurgical techniques in treatment of large and giant ICA aneurysms are the methods of choice in complex non-standard cases where endovascular treatment is ineffective or contraindicated. Planning of microsurgical treatment should include the possibility of revascularization surgery. Treatment of these patients should be carried out at large dedicated centers having appropriate expertise and facilities.

[Neurosurgery in a patient on dual antiplatelet therapy. Case report and the review of the literature]

INTRODUCTION

A neurosurgical intervention in a patient on dual antiplatelet therapy is a serious challenge for both the neurosurgeon and anesthesiologist..

MATERIAL AND METHODS

The article describes a clinical case of a successful urgent neurosurgical intervention (ventriculoperitoneostomy for obstructive hydrocephalus caused by a large meningioma of the posterior surface of the petrous pyramid) in a patient on dual antiplatelet therapy (DAT) due to a recently placed coronary stent..

CONCLUSION

Given a high risk of coronary stent thrombosis, the surgery was performed in the presence of ongoing DAT. There were no intracranial hemorrhagic complications, but subcutaneous hemorrhagic complications developed. The article discusses the features of managing similar patients whose number is growing.

[Giant partially thrombosed aneurysm of the vertebral artery: a case report and literature review]

INTRODUCTION

Giant partially thrombosed aneurysms of the vertebral artery are recalcitrant to treatment by microsurgical trapping and thrombectomy. Application of endovascular interventions is limited due to substantial brainstem compression and cranial nerve neuropathy. Combined endovascular exclusion and microsurgical excision provides an approach to treatment of these lesions.

CLINICAL CASE

A 48-year-old female patient presented with progressive complaints of ataxia, diplopia in left lateral gaze, and dysphagia. Imaging studies (CT, MRI, angiography) revealed a giant partially thrombosed aneurysm of the right vertebral artery and pronounced brainstem compression.

TREATMENT

The initial phase of treatment involved endovascular occlusion of the vertebral artery and aneurysm trapping that did not lead to changes in the postoperative patient's neurological status. MRI demonstrated complete aneurysm thrombosis and a weak TOF signal in the vertebral artery near the proximal aneurysm neck region. Because of persistent brainstem compression, the patient underwent right suboccipital craniectomy and hemilaminectomy of the CI arch for aneurysm excision one week after endovascular occlusion. After isolating the aneurysmal sac, the vertebral artery was transected, and two small branches extending from the aneurysm neck to the brainstem were also coagulated and transected, followed by aneurysm excision. Numerous vasa vasorum in the wall of the proximal vertebral artery and aneurysm neck were coagulated to stop bleeding. After surgery, the patient developed neurological symptoms (right leg ataxia and dysphagia worsening) due to lateral medullary infarction (confirmed by MRI) that presumably resulted from coagulation of two small perforating branches coming from the aneurysm neck to the brainstem. Recovery of the patient's neurological functions was observed during conservative treatment. The patient was discharged with mild right leg ataxia and preoperative left-sided abducens paresis.

CONCLUSION

Medulla oblongata compression associated with a giant thrombosed aneurysm of the vertebral artery can be eliminated by endovascular trapping followed by surgical excision of the aneurysm. Preserving the vasa vasorum feeding the brainstem is crucial for prevention of ischemic complications.