Surgical reconstruction of the extracranial vertebral artery: management and outcome

PURPOSE

The purpose of this study was to identify the risk and outcome of reconstruction of the extracranial vertebral artery (ECVA).

METHOD

The study was conducted as a retrospective review of 369 consecutive ECVA reconstructions.

RESULTS

The clinical presentations consisted of hemispheric symptoms alone in 4% of the cases, hemispheric and vertebrobasilar symptoms in 30%, and vertebrobasilar symptoms alone in 60%. The cause of the lesion was atherosclerosis (n = 300), extrinsic compression (n = 42), dissection (n = 7), radiation arteritis (n = 5), intimal hyperplasia (n = 3), fibromuscular dysplasia (n = 2), previous surgical ligation (n = 3), aneurysm (n = 2), and other (n = 5). All the patients underwent preoperative arteriography. There were 252 proximal ECVA reconstructions (218 transpositions, 42 bypass grafting procedures, and two other) and 117 distal ECVA reconstructions (85 bypass grafting procedures, 25 transpositions, and seven other). In 83 patients, the ECVA operation was performed concomitant with a carotid or supraaortic trunk reconstruction. This series was analyzed in two separate sets: before 1991 (n = 215), when changes in indications and management were occurring; and after 1991 (n = 154), when we acquired a dedicated anesthesia team and digital arteriography in the operating room and established uniform protocols for the management of ECVA disease. The stroke, death, and stroke/death rates for the period before 1991 were, respectively, 4. 1%, 3.2% and 5.1%. The stroke, death, and stroke/death rates for the period after 1991 were, respectively, 1.9%, 0.6% and 1.9%. The patency rate at 5 years was 80%. The survival rate at 5 years was 70%. Most of the deaths during the follow-up period were caused by cardiac disease. Among the survivors, the protection rate from stroke was 97%.

CONCLUSION

The changes in operative selection and management have improved the results of ECVA reconstruction. The data reported for ECVA reconstruction in patients who underwent operation since 1991 reflect the outcome of ECVA reconstruction today. In our experience, a reconstruction of the ECVA is less risky than a carotid reconstruction.

Endovascular approaches to acute stroke, part 2: a comprehensive review of studies and trials

Reperfusion remains the mainstay of acute ischemic stroke treatment. Endovascular therapy has become a promising alternative for patients who are ineligible for or have failed intravenous (IV) thrombolysis. The conviction that recanalization of properly selected patients is essential for the achievement of good clinical outcomes has led to the rapid and widespread growth in the adoption of endovascular stroke therapies. However, comparisons of the recent reperfusion studies have brought into question the strength of the association between revascularization and improved clinical outcome. Despite higher rates of recanalization, the mechanical thrombectomy studies have demonstrated substantially lower rates of good outcomes compared with IV and/or intra-arterial thrombolytic trials. However, such analyses disregard important differences in clot location and burden, baseline stroke severity, time from stroke onset to treatment, and patient selection in these studies. Many clinical trials are testing novel devices and drugs as well as the paradigm of physiology-based stroke imaging as a treatment-selection tool. The objective of this article is to provide a comprehensive review of the relevant past, current, and upcoming data on endovascular stroke therapy with a special focus on the prospective studies and randomized clinical trials.

Hemorrhagic Moyamoya Disease in Children: Clinical, Angiographic features, and Long-Term Surgical Outcome

BACKGROUND AND PURPOSE

Here, we describe the clinical, angiographic characteristics, and long-term surgical outcome of hemorrhagic moyamoya disease in children.

METHODS

We retrospectively collected 374 consecutive children with moyamoya disease (hemorrhagic 30 and ischemic 344) between 2004 and 2012 in our hospital. The clinical and radiological characteristics of the hemorrhagic patients were retrospectively described and analyzed. All the hemorrhagic patients underwent encephalo-duro-arterio-synangiosis procedure. Digital subtraction angiography was performed to evaluate the efficacy of vascularization. Clinical follow-up outcomes were obtained through clinical visits, telephone, or letter interview.

RESULTS

In our study, the ratio of female to male patients in the hemorrhagic group was significantly higher than the ischemic group (2:1 versus 0.9:1; P<0.05). The most frequent hemorrhagic location was intraventricular hemorrhage (n=22, 73%). In addition, significantly greater dilatation of the anterior choroidal artery and the posterior communicating artery were seen in the hemorrhagic group (P<0.05). Good or fair vascularization were observed in all the 15 children with digital subtraction angiography follow-up. Clinical outcomes showed that 25 of 30 (83%) patients had no disability (modified Rankin scale score, 0 and 1); 1 patient (3.3%) died of recurrent hemorrhagic stroke.

CONCLUSIONS

The presence of anterior choroidal artery and posterior communicating artery dilation may be associated with the bleeding episode in the children with hemorrhagic moyamoya disease. The encephalo-duro-arterio-synangiosis surgery can effectively increase the cerebral blood flow in children, which may decrease the incidence of recurrent hemorrhage.

Extracranial-intracranial bypass for the treatment of cavernous sinus aneurysms

The optimal management of symptomatic cavernous sinus aneurysms remains controversial. Carotid occlusion is a simple procedure, but carries an ongoing risk of early and late stroke. Cerebral revascularisation is technically demanding and carries a risk of morbidity and mortality of around 10%. Eight patients treated with an extracranial-intracranial vascular bypass graft over a period of 44 months for symptomatic cavernous sinus aneurysms are reviewed. At a mean follow-up of 20 months, seven patients (87.5%) had an excellent outcome (Glasgow Outcome Score 5) while one patient suffered a perioperative stroke. In only one case, where the radial artery had been used, the graft became occluded. The results of this series seem to indicate that cerebral revascularisation is an effective treatment for patients with symptomatic cavernous sinus aneurysms.

The ELANA technique: high flow revascularization of the brain

High flow revascularization of the brain is hampered by the fact that temporary occusion of a major cerebral artery is necessary to create the distal anastomosis, which may result in brain ischemia. The excimer laser-assisted non-occlusive anastomosis (ELANA) technique circumvents this problem. In this paper we elucidate the development of a non-occlusive way to make anastomoses to the major cerebral arteries.

Editor's Choice - Risk of Stroke before Revascularisation in Patients with Symptomatic Carotid Stenosis: A Pooled Analysis of Randomised Controlled Trials

OBJECTIVE

Current guidelines recommending rapid revascularisation of symptomatic carotid stenosis are largely based on data from clinical trials performed at a time when best medical therapy was potentially less effective than today. The risk of stroke and its predictors among patients with symptomatic carotid stenosis awaiting revascularisation in recent randomised controlled trials (RCTs) and in medical arms of earlier RCTs was assessed.

METHODS

The pooled data of individual patients with symptomatic carotid stenosis randomised to stenting (CAS) or endarterectomy (CEA) in four recent RCTs, and of patients randomised to medical therapy in three earlier RCTs comparing CEA vs. medical therapy, were compared. The primary outcome event was any stroke occurring between randomisation and treatment by CAS or CEA, or within 120 days after randomisation.

RESULTS

A total of 4 754 patients from recent trials and 1 227 from earlier trials were included. In recent trials, patients were randomised a median of 18 (IQR 7, 50) days after the qualifying event (QE). Twenty-three suffered a stroke while waiting for revascularisation (cumulative 120 day risk 1.97%, 95% confidence interval [CI] 0.75 - 3.17). Shorter time from QE until randomisation increased stroke risk after randomisation (χ2 = 6.58, p = .011). Sixty-one patients had a stroke within 120 days of randomisation in the medical arms of earlier trials (cumulative risk 5%, 95% CI 3.8 - 6.2). Stroke risk was lower in recent than earlier trials when adjusted for time between QE and randomisation, age, severity of QE, and degree of carotid stenosis (HR 0.47, 95% CI 0.25 - 0.88, p = .019).

CONCLUSION

Patients with symptomatic carotid stenosis enrolled in recent large RCTs had a lower risk of stroke after randomisation than historical controls. The added benefit of carotid revascularisation to modern medical care needs to be revisited in future studies. Until then, adhering to current recommendations for early revascularisation of patients with symptomatic carotid stenosis considered to require invasive treatment is advisable.

Multidisciplinary treatment of posterior circulation ischemia

Compromise of blood flow to the brain leads to cerebral ischemia, which if left untreated may even result in cerebral infarction. This has been the main cause of major morbidity and mortality over the years in the US and around the world. Cerebral ischemia to the posterior fossa is more critical and difficult to treat. This is primarily due to complex anatomy and physiology of the posterior fossa cerebal circulation. There has been multiple modalities tested over the years to treat posterior fossa ischemia which have definitely contributed in the outcome in patients with this complex problem. Improving the blood flow in the areas of brain at risk in properly selected patients could prevent impending cerebral ischemia and infarction. Today, there are mainly three types of treatment offered to patients with posterior cerebral ischemia. These are (a) medical, (b) endovascular and (c) surgical. The recent advances in technology, the diagnosis and mode of therapy, has definitely improved the outcomes of cerebral ischemia. We discuss the multidisciplinary treatment of posterior circulation ischemia. Various pre-operative and operative techniques involved in treating patients with posterior cerebral ischemia are discussed.

Extracranial-intracranial arterial bypass for treatment of occlusion of the internal carotid artery

Extracranial-intracranial arterial bypass was frequently utilized in the 1970s and early 1980s to treat patients with atherosclerotic occlusive carotid arterial lesions not amenable to extracranial arterial revascularization procedures. After a large randomized trial reported in 1985 that there was no benefit of surgery in these patients, the procedure was generally abandoned as a treatment for symptomatic atherosclerotic cerebrovascular disease. In the past two decades, multiple studies have shown that patients with impaired cerebral hemodynamics distal to an occlusive cerebrovascular lesion have a significantly increased risk of subsequent stroke. Two new randomized, controlled clinical trials of extracranial-intracranial arterial bypass in patients with symptomatic atherosclerotic occlusive cerebrovascular disease that are using cerebral hemodynamic criteria for patient selection are currently in progress. At the present time, extracranial-intracranial arterial bypass should not be performed on these patients outside of a clinical trial.

Stagnation of treatment times over a decade: results of a pooled analysis from the MERCI registry, MERCI, TREVO, and TREVO 2 trials

BACKGROUND

There has been a growing interest in improving systems of care for the endovascular treatment of acute ischemic stroke. We analyzed data from previous registries and studies to determine if there has been an improvement in times to reperfusion with increasing experience.

METHODS

We analyzed the pooled data from the Multi Mechanical Embolus Removal in Cerebral Ischemia (MERCI), MERCI Registry and Thrombectomy Revascularization of Large Vessel Occlusions (TREVO), and TREVO 2 trials and assessed times from last known normal to puncture, from hospital arrival to puncture, and procedure duration by year to determine if there has been a reduction in times. Demographic, radiographic, and clinical information were also assessed in a multivariate regression analysis to determine the predictors of good outcomes defined as a modified Rankin Scale score of 0-2 at 3 months.

RESULTS

1248 patients of mean age 68±14 years and median NIH Stroke Scale score 18 were analyzed from 2001 to 2011. Procedure times showed a significant improvement while last known normal to puncture times remained static. In multivariate logistic regression analysis, longer last known normal to puncture time and longer procedure duration were associated with a decreased chance of a good outcome (OR 0.84, 95% CI 0.76 to 0.92, p=0.0004 and OR 0.75, 95% CI 0.61 to 0.91, p=0.0040, respectively).

CONCLUSIONS

Despite a reduction in procedure times, there has not been a corresponding improvement in overall last known normal to puncture times over a 10-year period. The current study shows that there are many opportunities to create more efficient endovascular stroke systems of care in trials.

Management of patients with symptomatic carotid artery occlusion

The annual risk of stroke in patients with symptomatic carotid artery occlusion (CAO) and impaired cerebral blood flow (CBF) is approximately 10%. Increased oxygen extraction fraction measured by positron emission tomography (PET) and low cerebrovascular reactivity assessed by transcranial Doppler is associated with an increased risk of recurrent ischemic stroke in these patients. Recently, other risk factors have been identified: (1) symptoms of purported hemodynamic origin; (2) ongoing symptoms in the presence of documented symptomatic CAO; (3) leptomeningeal collaterals visible on angiography; and (4) low NAA/choline ratio on magnetic resonance (MR) spectroscopy. Evidence is growing that a second extracranial-intracranial (EC-IC) bypass trial might be worthwhile in patients with symptomatic CAO. Probably, only patients with ongoing symptoms and compromised CBF should be included in such a trial. Current evidence based therapeutic options for patients with symptomatic CAO include antithrombotic medication and control of vascular risk factors. For stenosis of the contralateral internal or ipsilateral external carotid artery endarterectomy may be considered. Ongoing symptoms may cease after tapering of antihypertensive medication.

Encephaloduroarteriosynangiosis Averts Stroke in Atherosclerotic Patients With Border-Zone Infarct: Post Hoc Analysis From a Performance Criterion Phase II Trial

BACKGROUND

Intracranial atherosclerotic disease (ICAD) is one of the leading causes of stroke worldwide. Patients with ICAD who initially present with ischemia in border-zone areas and undergo intensive medical management (IMM) have the highest recurrence rates (37% at 1 yr) because of association with hemodynamic failure and poor collaterals.

OBJECTIVE

To evaluate the effect of encephaloduroarteriosynagiosis (EDAS) on stroke recurrence in patients with ICAD and border-zone stroke (BDZS) at presentation.

METHODS

A phase II clinical trial of EDAS revascularization for symptomatic ICAD failing medical management (EDAS Revascularization for Symptomatic Intracranial Atherosclerosis Steno-occlusive [ERSIAS]) was recently concluded. We analyze the outcomes of the subgroup of patients with BDZS at presentation treated with EDAS vs the previously reported Stenting versus Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis (SAMMPRIS) IMM subgroup with BDZS at presentation.

RESULTS

Of 52 patients included in the ERSIAS trial, 35 presented with strokes at baseline, and 28 had a BDZ pattern, including 15 (54%) with exclusive BDZS and 13 (46%) with mixed patterns (BDZ plus other distribution). Three of the 28 (10.7%) had recurrent strokes up to a median follow-up of 24 months. The rate of recurrent stroke in ICAD patients with BDZS at presentation after EDAS was significantly lower than the rate reported in the SAMMPRIS IMM subgroup with BDZS at presentation (10.7% vs 37% P = .004, 95% CI = 0.037-0.27).

CONCLUSION

ICAD patients with BDZS at presentation have lower rates of recurrent stroke after EDAS surgery than those reported with medical management in the SAMMPRIS trial. These results support further investigation of EDAS in a randomized clinical trial.

Functional connectivity analysis and prediction of cognitive change after carotid artery stenting

OBJECTIVE

The neurocognitive course of patients who have undergone cerebral revascularization has been the subject of many studies, and the reported effects of carotid artery stenting (CAS) on cognitive function have varied from study to study. The authors hypothesized that cognitive amelioration after CAS is associated with alteration of the default mode network (DMN) connectivity, and they investigated the correlation between functional connectivity (FC) of the DMN and post-CAS changes in cognitive function in order to find a clinical marker that can be used to predict the effect of cerebral revascularization on patients' cognitive function in this preliminary exploratory study.

METHODS

The authors examined post-CAS changes in cognitive function in relation to FC in patients treated for unilateral carotid artery stenosis. Resting-state functional MRI (rs-fMRI) was performed with a 3-T scanner before and 6 months after CAS in 8 patients. Neuropsychological tests (Wechsler Adult Intelligence Scale III and Wechsler Memory Scale-Revised) were administered to each patient before and 6 months after CAS. The DMN was mapped for each patient through independent component analysis of the rs-fMR images, and the correlation between FC of the DMN and post-CAS change in cognitive function was analyzed on a voxel level. Multivariable regression analysis was performed to identify preoperative factors associated with a post-CAS change in cognitive function.

RESULTS

Post-CAS cognitive function varied between patients and between categories of neuropsychological tests. Although there was no significant overall improvement in Working Memory scores after CAS, post-CAS Working Memory scores changed in negative correlation with changes in FC between the DMN and the precentral/superior frontal gyrus and between the DMN and the middle frontal gyrus. In addition, the preoperative FC between those areas correlated positively with the post-CAS improvement in working memory.

CONCLUSIONS

FC between the DMN and working memory-related areas is closely associated with improvement in working memory after CAS. Preoperative analysis of FC of the DMN may be useful for predicting postoperative improvement in the working memory of patients being treated for unilateral stenosis of the extracranial internal carotid artery.Clinical trial registration no.: UMIN000020045 (www.umin.ac.jp/ctr/index.htm).

Revascularization surgery for symptomatic non-moyamoya intracranial arterial stenosis or occlusion

OBJECTIVE

Previous trials rejected a role of extracranial-to-intracranial bypass surgery for managing symptomatic atheromatous disease. However, hemodynamic insufficiency may still be a rationale for surgery, provided the bypass can be performed with low morbidity and patency is robust.

METHODS

Consecutive patients undergoing bypass surgery for symptomatic non-moyamoya intracranial arterial stenosis or occlusion were retrospectively identified. The clinical course and surgical outcomes of the cohort were evaluated at 6 weeks, 6 months, and annually thereafter.

RESULTS

From 1992 to 2017, 112 patients underwent 127 bypasses. The angiographic abnormality was arterial occlusion in 80% and stenosis in 20%. Procedures were performed to prevent future stroke (76%) and stroke reversal (24%), with revascularization using an arterial pedicle graft in 80% and venous interposition graft (VIG) in 20%. A poor outcome (bypass occlusion, new stroke, new neurological deficit, or worsening neurological deficit) occurred in 8.9% of patients, with arterial pedicle grafts (odds ratio [OR] 0.15), bypass for prophylaxis against future stroke (OR 0.11), or anterior circulation bypass (OR 0.17) identified as protective factors. Over the first 8 years following surgery the 66 cases exhibiting all three of these characteristics had minimal risk of a poor outcome (95% confidence interval 0%-6.6%).

CONCLUSIONS

Prophylactic arterial pedicle bypass surgery for anterior circulation ischemia is associated with high graft patency and low stroke and surgical complication rates. Higher risks are associated with acute procedures, typically for posterior circulation pathology and requiring VIGs. A carefully selected subgroup of individuals with hemodynamic insufficiency and ischemic symptoms is likely to benefit from cerebral revascularization surgery.

dl-3-n-butylphthalide for alleviation of neurological deficit after combined extracranial-intracranial revascularization for moyamoya disease: a propensity score-matched analysis

OBJECTIVE

Postoperative neurological deficits impair the overall outcome of revascularization surgery for patients with moyamoya disease (MMD). dl-3-n-butylphthalide (NBP) is approved for the treatment of ischemic stroke in China. This pilot study evaluated the effect of NBP on perioperative stroke and neurological deficits in patients with MMD.

METHODS

The authors studied cases in which patients underwent combined revascularization surgery for MMD at their institution, with or without NBP administration. The overall study group included 164 patients (213 surgically treated hemispheres), including 49 patients who received NBP (25 mg twice daily) for 7 postoperative days. The incidence of perioperative stroke and transient neurological deficit (TND) and the severity of neurological deficits were compared between 49 propensity score-matched case pairs with or without NBP treatment. Subgroup analyses by type of onset and preoperative neurological status were also performed to determine specific characteristics of patients who might benefit from NBP administration.

RESULTS

In the overall cohort, baseline characteristics differed with respect to preoperative stroke and modified Rankin Scale (mRS) score between patients who received NBP and those who did not receive it. In the 49 propensity score-matched pairs, postoperative stroke was observed in 11 patients and TND occurred in 21 patients, with no significant difference in incidence between the 2 groups. However, the TND was less severe in the NBP-treated group (p = 0.01). At 1 month after surgery, the neurological outcome was more favorable (p = 0.001) and the disability-free recovery rate was higher in patients with NBP treatment (p < 0.001). The number of patients who experienced an improved neurological function, compared to preoperative function, as measured by mRS, was greater in the NBP group than in the no-NBP group (p < 0.001). Multivariable analysis revealed that NBP administration was associated with decreased severity of TND (OR 0.28, p = 0.02), improved neurological function (OR 65.29, p = 0.04), and lower postoperative mRS score (OR 0.06, p < 0.001). These beneficial effects of NBP remained significant in ischemic type MMD and patients with preoperative mRS scores of 2 or greater.

CONCLUSIONS

Postoperative administration of NBP may alleviate perioperative neurological deficits after revascularization surgery for MMD, especially in patients with ischemic MMD and unfavorable preoperative status. The results of this study suggest that randomized controlled trials to assess the potential benefit of NBP in patients with MMD may be warranted.

Future of extracranial-intracranial bypass

Total occlusion of internal carotid artery in the cervical region is an end result of progressive occlusive vascular disease. A small proportion of these patients will have symptoms of cerebral ischemia due to cerebral hypoperfusion in a delayed fashion. Identification of those individuals who are at risk of developing symptoms and prophylactically treating with a revascularization procedure will prevent such catastrophic events. With the co-operative study for bypass not supporting the bypass procedure and trial being questioned for its design and conclusions, a new trial of extracranial-intracranial bypass, The Carotid Occlusion Surgery Study, using the currently available technology will be undertaken to verify that the bypass will decrease the future stroke rate by at least 40% in patients with total carotid occlusion. A subset of patients with skull base pathology including tumors and aneurysms who may have to undergo carotid sacrifice as part of the surgical procedure are at risk of peri-operative and delayed stroke. Identification of these patients at risk by pre-operative tests may allow performance of extracranial-intracranial bypass prior to undertaking complex skull base procedures. The new imaging technology will guide management of these patients at risk and help identify patients who may need a bypass procedure.

Early Neutrophil-to-Lymphocyte Ratio Is a Prognostic Marker in Acute Ischemic Stroke After Successful Revascularization

OBJECTIVE

To explore the association between early neutrophil-to-lymphocyte ratio (ENLR) and prognosis of anterior circulation large-vessel occlusion stroke (LVOS) after patients undergo endovascular treatment (EVT) with successful revascularization.

METHODS

Patients who experienced acute anterior circulation LVOS and underwent EVT at Changzhou Second People's Hospital Affiliated to Nanjing Medical University between May 2017 and May 2020 were included in this retrospective study. We collected information about patients' baseline characteristics, medical history, laboratory test results, imaging data, and endovascular treatment outcomes, as well as data from follow-up at 3 months. Univariate and multivariate logistic regression models were used to evaluate the association between ENLR and functional disease prognosis. A piecewise linear regression model was also applied to compute the threshold effect of ENLR on poor prognosis (defined as modified Rankin Scale score 3-6) at 3 months using a smoothing plot.

RESULTS

Of 224 patients who received EVT during the study period, 160 patients were included in the analysis. After adjustments were made for potential confounders, multivariate analysis demonstrated a significant association between ENLR and poor prognosis at 3 months (odds radio 1.19; 95% confidence interval 1.07-1.32; P = 0.0016). An ENLR ≥9.75 was found to be significantly associated with poor prognosis at 3 months (odds ratio 1.54; 95% confidence interval 1.19-2.00; P = 0.0119).

CONCLUSIONS

Increased ENLR after successful revascularization is independently associated with poor prognosis. These findings suggest that ENLR could be used to inform treatment strategies for patients who experience anterior circulation LVOS.

Electromagnetic therapeutic angiogenesis: the next step

Therapeutic angiogenesis, in the form of growth factor protein administration or gene therapy, is a new method of treatment for patients with severe coronary and peripheral artery disease not amenable to conventional methods of revascularization. Furthermore, a new experimental strategy increases endogenous angiogenesis in ischemic tissue to induce local 'angiogens' by means of electromagnetic stimulation. Further studies examining the molecular basis and clinical efficacy of electromagnetic angiogenesis are necessary.

Failures in Revascularization for Pediatric Moyamoya Disease and Syndrome: A Scoping Review

BACKGROUND

Moyamoya disease (MMD) and moyamoya syndrome (MMS) are a rare cause of stroke commonly managed surgically. We conducted a scoping review to identify the current scope of the literature regarding factors associated with failure of revascularization surgery for MMD and MMS in pediatric patients and to catalyze future research.

METHODS

A scoping review was conducted to explore failures of revascularization surgery for MMD and MMS in pediatric patients using the PubMed, Embase, and Scopus databases. Titles and abstracts returned from searches were screened for full-text review. Studies meeting inclusion criteria were reviewed in full, and relevant data were extracted.

RESULTS

Of 2450 resultant articles, 15 were included. Angiographic outcomes were reported for 900 hemispheres, of which 442 (49.1%) were denoted as Matsushima grade A, 299 (33.2%) as Matsushima grade B, and 159 (17.7%) as Matsushima grade C. Patients with MMS had poorer angiographic outcomes than did patients with MMD. Patients with poor neovascularization had a greater degree of moyamoya vessels on follow-up angiogram. Suzuki stage was not associated with angiographic outcome in individual patients. Angiographic outcomes differed by surgical approach and were not associated with clinical outcomes. Literature identifying factors was sparse.

CONCLUSIONS

The existing literature indicates that factors such as cause, degree of moyamoya vessels, and surgical approach may affect the likelihood of Matsushima grade C revascularization in pediatric patients with MMD and MMS. Future studies are necessary to definitively elucidate factors associated with failure of revascularization surgery for pediatric MMD.

[On the occasion of my retirement as head of the Neurochirurgische Universitätsklinik Zürich--changing aspects of treatment modality in modern neurosurgery and of neuroscience research. Presentation of our experience and historical backgrounds]

On the occasion of my retirement as head of the Neurochirurgische Universitätsklinik Zürich on 31. May 2007, the changing aspects of neurosurgery in diseases dealt with and in their treatments during the last 70 years (from the foundation of the department by Prof. Krayenbuehl in 1937 successed by Prof. Yaşargil and later on by myself.) were presented. Number of surgical procedures were 1,000 times per year during the interval and the busiest era was that of Prof. Krayenbühl, in which it amounted to as much as 1,500 at the maximum. Lumbar disc surgery was the most frequent one (around 250/year with the use of more than 70 beds) and this belonged to the beginning of the resident's surgical training program. This is now mainly performed by neurosurgeons in practice outside of the university hospital. Although "new" technique such as Chymopapain injection or endoscopic methods have been applied, microsurgical lumbar disc surgery remains as the gold standard. Newly the situation of medical economics has changed dramatically. One is forced to adapt oneself more or less to this change, so that these 1,000 surgeries/year could be performed using 30 beds. Vascular neurosurgery has changed considerably in its aspects from development of microsurgery pioneered by Prof. Yaşargil at the end of 1960 and to the endovascular methods by Serbinenco, Grüntzig in 1970s followed by Guglielmi's electrothrombosis at the end of 1980. Our cases of aneurysm clipping decreased from 100 (1993) to 80 (2006), while cases of aneurysm coiling increased from 40 (1993) to 60 (2006). Long-term follow-up results of endovascular methods are still to be evaluated for the final judgement of appropriateness of this tendency. AVMs are now mainly treated with endovascular method (70/year) and their microsurgical removal of AVMs is usually performed in combination with hematoma removal in the acute stage (20/year). Gamma-knife application for AVMs were rare. Traditionally, carotid endarterectomy belonged to vascular surgeons in our hospital, but the tendency of conversion from conventional carotid endarterectomy to endovascular PTA and/or stenting seemed to be marked, while microvascular revascularization procedure represented by extracranial intracranial EC-IC bypass remained constant (around 20/year) in various occasion (277 times on 203 cases: atherosclerosis 93, Moyamoya angiopathy (MMA) 47, aneurysm 57 and skull base tumour 6, during the last 13 years], in spite of negative results of EC-IC bypass international cooperative study for stroke prevention in 1985. Glioma surgery especially glioblastoma surgery the most frequent surgery in our department around 170 / year contributed to improvement of both life expectancy and quality of life by development of therapy modalities (irradiation microsurgery and chemotherapy). Recent life expectancy of cases with primary glioblastoma amounted to 25.8 ms on the average by combination of treatments; microsurgical gross total removal + irradiation + temodal and thalidomide. This was 8.5 ms and 14 ms respectively at the time of Prof. Krayenbühl 1960 (surgical removal plus irradiation) and of Prof. Yaşargil 1970 (microsurgical removal plus irradiation) and these results being those on cases of primary and secondary glioblastoma together. Postoperative quality of life improved also by using modern techniques: intraoperative stimulation, cortical mapping, navigation, open MRI etc.. Acoustic neurinoma (just less than 20/year) is one of benign brain tumours whose treatment has changed remarkably. Cases were referred to us only when their size exceeded 2-3 cm in extrameatal diameter, as the smaller ones are treated by Gamma-knife. Thanks to development of intaroperative neurophysiological monitoring and of surgical technique, preservation of facial nerve function has improved from 60% to more than 85% in spite of the increase of size. Functional neurosurgery represented by microvascular decompression for hemifacial spasm and trigeminal neuralgia pioneered by Prof. Jannetta and by the selective amgdalohippocampectomy SAHE for intractable mesial temporal lobe epilepsy MTLE pioneered by Prof. Yaşargil both in 1970s were around 20/year respectively. Recently stereotactic intervention decreased remarkably. Shunting procedure for hydrocephalus malresorptivus (after subarachnoid hemorrhage and/or idiopathic) were around 100/year. Programmable valve (opening pressure can be changed magnetically percutaneously) has increased clinical effectiveness of the shunt. It was the authors pleasure to have succeeded the Neurochirurgische Universitätsklinik Zürich directed by two foregoing giant neurosurgeons Prof. Krayenbühl and Prof. Yaşargil and therefore to have completed a hard task more or less and have experienced considerable changing aspects of modern neurosurgery as mentioned above.

Stroke prevention: is surgery more effective than therapy?

Experts say the emphasis on research has produced a major success story during the past dozen years. For example, more than 194,000 fatal strokes were reported in this country in 1975, a rate of 91.1 per 100,000. By 1981, that figure had declined to 163,504 with a corresponding drop in the rate per 100,000 in the general population. In 1985, the last year for which numbers are available, the provisional count was 151,810 cases of fatal stroke and a rate of 64 per 100,000. Thus, since 1975, the nation has seen a 30 percent decline in fatal strokes, attributed at least in part to vigorous research.

Post-anesthesia care unit delirium in children with moyamoya disease undergoing indirect revascularization: incidence and risk factors

BACKGROUND

Delirium in the post-anesthesia care unit (PACU) may be associated with worse outcomes in children with moyamoya disease (MMD). This retrospective study aimed to describe the prevalence of PACU delirium in children with MMD and investigate its risk factors.

METHODS

Patients with MMD aged < 15 years who underwent indirect revascularization between January 2014 and October 2023 were included in this study. Delirium was assessed using the Pediatric Anesthesia Emergence Delirium Scale. Potential risk factors for PACU delirium were evaluated using multivariate logistic regression.

RESULTS

PACU delirium occurred in 245 (33%) of the 750 hemispheric procedures performed in 522 patients. Delirium was associated with a higher incidence in patients undergoing the first revascularization (37%) than in those undergoing the second (25%; P = 0.002). Cerebral infarction as the initial presentation (odds ratio [OR]: 4.64, first revascularization), high pediatric moyamoya magnetic resonance imaging (MRI) score (OR: 2.75, first revascularization; OR: 3.50, second revascularization), and high intraoperative mean arterial pressure variability (mmHg/min) (OR: 9.17, first revascularization; OR: 8.82, second revascularization) were associated with PACU delirium. Conversely, total intravenous anesthesia (TIVA) was associated with a lower incidence of PACU delirium (OR: 0.46, first revascularization; OR: 0.25, second revascularization).

CONCLUSIONS

A significant proportion of patients with MMD developed delirium in the PACU. High intraoperative blood pressure variability and preoperative MRI lesions are independent risk factors for PACU delirium in children with MMD. TIVA may exert a protective effect against PACU delirium. Further studies are required to clarify the causality of these associations.