[Endovascular Treatment of Delayed Cerebral Vasospasms].

Delayed cerebral vasospasm is a major complication following subarachnoid hemorrhage and a primary cause of delayed cerebral ischemia. While various preventive treatments exist, some patients still develop severe vasospasm, highlighting the need for better rescue therapies. This article explores endovascular treatment as a rescue option for vasospasm, focusing on the clinical characteristics and roles of intra-arterial vasodilator injection therapy and percutaneous transluminal angioplasty(PTA). Despite a lack of strong evidence from large clinical trials, advancements in endovascular technology have positioned both intra-arterial vasodilator injection therapy and PTA as promising and safe rescue options for severe vasospasm. Careful selection of the appropriate approach is crucial for achieving optimal clinical outcomes, considering the unique characteristics, advantages, and limitations of each method. Further clinical trials are necessary to definitively confirm this hypothesis.

Sustained efficacy of angioplasty for cerebral vasospasm after aneurysmal subarachnoid hemorrhage: Risk features and device comparison.

BACKGROUND: Cerebral vasospasm is a leading source of delayed morbidity and mortality after aneurysmal subarachnoid hemorrhage (aSAH). Angioplasty may improve vasospasm, while optimal target and device selection remains controversial. This study aimed to identify features and devices associated with sustained efficacy. METHODS: We identified consecutive patients who underwent angioplasty for aSAH vasospasm. The primary outcome was a composite of adequate angioplasty (residual narrowing < 50 %) without complications. Secondary outcomes included rates of refractory/recurrent vasospasm and sustained improvement at follow-up. Associated features were identified through multivariable analysis. Outcomes were compared between balloon and Comaneci/stentriever in a propensity-score-matched cohort. RESULTS: A total of 149 vasospastic segments underwent angioplasty: 61.7 % in the proximal anterior circulation (ICA, M1, A1), 20.1 % in distal segments (A2 and M2) and 18.1 % in the posterior circulation. Adequate angioplasty was achieved without complication in 83.2 % of vessels, with a sustainable effect in 84.3 % at follow-up. Refractory/recurrent vasospasm was observed in 17.4 %, yielding a 10.1 % retreatment rate. Notably, only 35.3 % of vessels undergoing inadequate angioplasty demonstrated improvement at follow-up. Angioplasty targeting distal MCA (adjusted OR, 0.10) or BA-V4 (aOR, 0.10), and inadequate angioplasty (aOR, 0.03) were unfavorable predictors for sustained improvement. Efficacy outcomes were similar between balloon and Comaneci/stentriever in a matched subgroup analysis. CONCLUSION: Angioplasty, when achieving residual narrowing < 50 %, demonstrated sustained improvement for vasospasm. Novel devices may exhibit comparable efficacy to balloon angioplasty for selected segments.

Electroacupuncture enhances cerebral blood perfusion by inhibiting HIF-1α in rat subarachnoid hemorrhage.

OBJECTIVE: Cerebral blood perfusion (CBP) reduction is a prevalent complication following subarachnoid hemorrhage (SAH) in clinical practice, often associated with long-term cognitive impairment and prognosis. Electroacupuncture (EA), a widely utilized traditional Chinese therapy for central nervous system disorders, has demonstrated promising therapeutic effects. This study aims to investigate the therapeutic potential of EA in restoring CBP in SAH rats and to explore the mechanisms involving HIF-1α in this process. METHODS: Rats were randomly assigned to one of five groups, including Sham, SAH, EA, EA + Saline, and EA + dimethyloxallyl glycine (DMOG) groups. EA treatment was administered for 10 min daily, while DMOG were intraperitoneally injected. Behavioral tests, cerebral blood flow monitoring, vascular thickness measurement, western blotting, and immunofluorescence staining were conducted to assess the therapeutic effects of EA on cerebral blood flow. RESULTS: SAH resulted in elevated levels of HIF-1α, endothelin (ET), ICAM-1, P-SELECTIN, E-SELECTIN, and decreased level of eNOS in the brain. This led to cerebral vasospasm, decreased CBF, and cognitive deficits in the rat SAH model. EA intervention downregulated the expression of HIF-1α, ET, ICAM-1, P-SELECTIN, and E-SELECTIN, while increasing eNOS expression. This alleviated cerebral vasospasm, restored CBF, and improved cognitive function. However, the administration of the HIF-1α stabilizer (DMOG) counteracted the therapeutic effects of EA. CONCLUSION: EA promotes the recovery of cerebral blood flow after SAH injury, attenuates cerebral vasospasm, and accelerates the recovery of cognitive dysfunction, and its mechanism of action may be related to the inhibition of the HIF-1α signaling pathway.

A Case of Pregnancy-Induced Hereditary Thrombotic Thrombocytopenic Purpura Complicated by Cerebral Vasospasm.

BACKGROUND: The aim was to explore the treatment of a case of congenital thrombotic thrombocytopenic purpura induced by pregnancy complicated with cerebral vasospasm. METHODS: We present a case study of congenital TTP where disease onset occurred during two separate pregnancies. Interestingly, the disease course exhibited distinct differences on each occasion. Additionally, following plasma transfusion therapy, there was a transient occurrence of cerebral vasospasm. RESULTS: In this case, ADAMTS13 levels reached their lowest point three days after delivery during the first pregnancy, triggering morbidity. Remarkably, a single plasma transfusion of 400 mL sufficed for the patient's recovery. Nonetheless, a recurrence of symptoms transpired during her second pregnancy at 24 weeks of gestation. Plasma transfusions were administered during and after delivery. Sudden convulsions developed. ADAMTS13 ac-tivity returned to normal, but cranial MRA revealed constrictions in the intracranial segments of both vertebral arteries, the basilar artery, and the lumen of the anterior, middle, and posterior cerebral arteries. A subsequent cranial MRA conducted a month later showed no lumen stenosis, indicating spontaneous recovery. CONCLUSIONS: These findings highlight the importance of careful consideration when administering plasma transfusions in congenital TTP during pregnancy. Moreover, the development of novel therapeutic approaches such as recombinant ADAMTS13 is crucial for minimizing complications and optimizing patient care.

Chemical angioplasty vs. balloon plus chemical angioplasty for delayed cerebral ischemia: a pilot study of PbtO2 outcomes.

BACKGROUND: Delayed cerebral ischaemia (DCI) is a major cause of morbidity and mortality after aneurysmal subarachnoid haemorrhage (aSAH). Chemical angioplasty (CA) and transluminal balloon angioplasty (TBA) are used to treat patients with refractory vasospasm causing DCI. Multi-modal monitoring including brain tissue oxygenation (PbtO2) is routinely used at this centre for early detection and management of DCI following aSAH. In this single-centre pilot study, we are comparing these two treatment modalities and their effects on PbtO2. METHODS: Retrospective case series of patients with DCI who had PbtO2 monitoring as part of their multimodality monitoring and underwent either CA or TBA combined with CA. PbtO2 values were recorded from intra-parenchymal Raumedic NEUROVENT-PTO® probes. Data were continuously collected and downloaded as second-by-second data. Comparisons were made between pre-angioplasty PbtO2 and post-angioplasty PbtO2 median values (4 h before angioplasty, 4 h after and 12 h after). RESULTS: There were immediate significant improvements in PbtO2 at the start of intervention in both groups. PbtO2 then increased by 13 mmHg in the CA group and 15 mmHg in the TBA plus CA group in the first 4 h post-intervention. This improvement in PbtO2 was sustained for the TBA plus CA group but not the CA group. CONCLUSION: Combined balloon plus chemical angioplasty results in more sustained improvement in brain tissue oxygenation compared with chemical angioplasty alone. Our findings suggest that PbtO2 is a useful tool for monitoring the response to angioplasty in vasospasm.

Recurrent thunderclap headache after endovascular embolization of pial AV malformation by onyx material.

Thunderclap headache is a sudden severe headache with onset to peak within one minute. Multiple excruciating, short-lived thunderclap headaches over a few days to weeks are highly suggestive of reversible cerebral vasoconstriction syndrome (RCVS). RCVS can be primary or secondary to several factors, but it is rarely described after neuro-endovascular procedures using onyx material. A 10-year-old child presented with RCVS heralded by recurrent thunderclap headache following endovascular embolization of pial arteriovenous malformation with onyx material (contains organic solvent dimethyl sulfoxide). Dimethyl sulfoxide is an angiotoxic material that can cause dysregulation of cerebral vascular tone triggering reversible cerebral vasoconstriction syndrome. Recurrent thunderclap headache after embolization procedures using onyx material should prompt for the diagnosis of reversible cerebral vasoconstriction syndrome.

Is Stent Retraction to ReLieve Arterial Cerebral VaSospasm Caused by SAH (Stent-ReLACSS) Using PRELAX the Long-awaited Solution for Treatment of Posthemorrhagic Cerebral Vasospasm? : Treatment of Posthemorrhagic Cerebral Vasospasm with PRESET and PRELAX: Technical Aspects, Efficacy, and Safety Margins in a Case Series.

PURPOSE: Recent observational studies have indicated the efficacy of stent retriever devices for the treatment of posthemorrhagic cerebral vasospasm (CVS), both by deployment and on-site withdrawal into the microcatheter (stent angioplasty, SA) and deployment followed by retraction through the target vessel similar to thrombectomy (Stent Retraction to reLieve Arterial Cerebral vaSospasm caused by SAH, Stent-ReLACSS). This article reports the findings with each application of pRESET and pRELAX in the treatment of CVS. METHODS: We retrospectively enrolled 25 patients with severe CVS following aneurysmal subarachnoid hemorrhage. For the SA group, a stent retriever or a pRELAX was temporarily deployed into a narrow vessel segment and retrieved into the microcatheter after 3 min. For the Stent-ReLACSS group, a pRELAX was temporarily deployed into a narrow vessel and pulled back unfolded into the internal carotid artery. If intra-arterial vasodilators were administered, they were given exclusively after mechanical vasospasmolysis to maximize the effectiveness of the stent treatment. RESULTS: In this study fifteen patients and 49 vessels were treated with SA. All were technically successful without periprocedural complications; however, 8/15 patients (53.3%) required additional treatment of the CVS. A total of 10 patients and 23 vessel segments were treated with Stent-ReLACSS. All maneuvers were technically successful without periprocedural complications and all vessels showed significant angiographic improvement. No recurrent CVS requiring further endovascular treatment occurred in-hospital, and neither territorial ischemia in the treated vessels nor vascular injury were observed in follow-up angiography. CONCLUSION: Based on the presented data it appears that Stent-ReLACSS with pRELAX does not pose any additional risks when used to treat CVS and might be superior to SA, especially concerning mid-term and long-term efficacy. The mechanism of action may be an effect on the endothelium rather than mechanical vasodilation. As many patients with CVS are diagnosed too late, prophylactic treatment of high-risk patients (e.g., poor grade, young, female) is potentially viable.

Neuroradiological diagnosis and therapy of cerebral vasospasm after subarachnoid hemorrhage. / Neuroradiologische Diagnostik und Therapie von zerebralen Vasospasmen nach Subarachnoidalblutung.

BACKGROUND: Cerebral damage after aneurysmal subarachnoid hemorrhage (SAH) results from various, sometimes unrelated causes. After the initial hemorrhage trauma with an increase in intracranial pressure, induced vasoconstriction, but also microcirculatory disturbances, inflammation and pathological electrophysiological processes (cortical spreading depolarization) can occur in the course of the disease, resulting in delayed cerebral ischemia (DCI). In the neuroradiological context, cerebral vasospasm (CVS) remains the focus of diagnostic imaging and endovascular therapy as a frequent component of the genesis of DCI. METHODS: The amount of blood leaked during aneurysm rupture (which can be detected by CT, for example) correlates with the occurrence and severity of CVS. CT perfusion is then an important component in determining the indication for endovascular spasm therapies (EST). These include intra-arterial drug administration (also as long-term microcatheter treatment) and mechanical procedures (balloon angioplasty, vasodilatation using other instruments such as stent retrievers, stenting). CONCLUSION: This review summarizes the current findings on the diagnosis and treatment of CVS after aneurysmal SAH from a neuroradiological perspective, taking into account the complex and up-to-date international literature. KEY POINTS: · Vasospasm is a frequent component of the multifactorial genesis of delayed cerebral ischemia after SAH and remains the focus of diagnosis and treatment in the neuroradiological context.. · The initial extent of SAH on CT is associated with the occurrence and severity of vasospasm.. · CT perfusion is an important component in determining the indication for endovascular spasm therapy.. · Endovascular spasm therapies include local administration of medication (also as long-term therapies with microcatheters) and mechanical procedures (balloon angioplasty, dilatation using other devices such as stent retreivers, stenting).. CITATION FORMAT: · Neumann A, Schacht H, Schramm P. Neuroradiological diagnosis and therapy of cerebral vasospasm after subarachnoid hemorrhage. Fortschr Röntgenstr 2024; 196: 1125 - 1133.

Treatment of Cerebral Vasospasm Following Aneurysmal Subarachnoid Hemorrhage using the Neurospeed Semi-compliant Balloon.

BACKGROUND AND PURPOSE: Cerebral vasospasm (CV) following aneurysmal subarachnoid hemorrhage (aSAH) may lead to morbidity and mortality. Endovascular mechanical angioplasty may be performed if symptomatic CV is refractory to noninvasive medical management. Off-label compliant remodelling balloons tend to conform to the course of the vessel, contrary to noncompliant or semi-compliant balloons. Our objective is to describe our initial experience with the semi-compliant Neurospeed balloon (approved for intracranial stenosis) in cerebral vasospasm treatment following aSAH. METHODS: All patients included in the prospective observational SAVEBRAIN PWI (NCT05276934 on clinicaltrial.gov) study who underwent cerebral angioplasty using the Neurospeed balloon for the treatment of medically refractory and symptomatic CV after aSAH were identified. Patient demographic information, procedural details and outcomes were obtained from electronic medical records. RESULTS: Between February 2022 and June 2023, 8 consecutive patients underwent CV treatment with the Neurospeed balloon. Angioplasty of 48 arterial segments (supraclinoid internal carotid artery, A1 and A2 segments of the anterior cerebral artery, M1 and M2 segments of the middle cerebral artery) was attempted and 44/48 (92%) were performed. The vessel diameter significantly improved following angioplasty (+81%), while brain hypoperfusion decreased (-81% of the mean TMax). There was no long-term clinical complication, 4% periprocedural complications occurred. CONCLUSION: The semi-compliant Neurospeed balloon is effective in the treatment of cerebral vasospasm following aSAH, bringing a new device into the armamentarium of the neurointerventionalist to perform intracranial angioplasty.

Evolving frontiers: endovascular strategies for the treatment of delayed cerebral ischemia.

Cerebral vasospasm and delayed cerebral ischemia represent a very challenging aspect of cerebrovascular pathophysiology, most commonly subarachnoid hemorrhage, with significantly high mortality if left untreated. Considerable advances have been made in medical treatment and prompt diagnosis, while newer endovascular modalities have recently been proposed for cases of resistant cerebral vasospasm. However, there is still paucity of data regarding which and whether a single endovascular technique is non inferior to the pharmacological standard of care. In this review, we aim to summarize the current funds of knowledge concerning cerebral vasospasm and the emerging role of the endovascular techniques for its treatment.

Interventional Treatment of Symptomatic Vasospasm in the Setting of Traumatic Brain Injury: A Systematic Review of Reported Cases.

Traumatic subarachnoid hemorrhage (tSAH) is frequently comorbid with traumatic brain injury (TBI) and may induce secondary injury through vascular changes such as vasospasm and subsequent delayed cerebral ischemia (DCI). While aneurysmal SAH is well studied regarding vasospasm and DCI, less is known regarding tSAH and the prevalence of vasospasm and DCI, the consequences of vasospasm in this setting, when treatment is indicated, and which management strategies should be implemented. In this article, a systematic review of the literature that was conducted for cases of symptomatic vasospasm in patients with TBI is reported, association with tSAH is reported, risk factors for vasospasm and DCI are summarized, and commonalities in diagnosis and management are discussed. Clinical characteristics and treatment outcomes of 38 cases across 20 studies were identified in which patients with TBI with vasospasm underwent medical or endovascular management. Of the patients with data available for each category, the average age was 48.7 ± 20.3 years (n = 31), the Glasgow Coma Scale score at presentation was 10.6 ± 4.5 (n = 35), and 100% had tSAH (n = 29). Symptomatic vasospasm indicative of DCI was diagnosed on average at postinjury day 8.4 ± 3.0 days (n = 30). Of the patients, 56.6% (n = 30) had a new ischemic change associated with vasospasm confirming DCI. Treatment strategies are discussed, with 11 of 12 endovascularly treated and 19 of 26 medically treated patients surviving to discharge. tSAH is associated with vasospasm and DCI in moderate and severe TBI, and patients with clinical and radiographic evidence of symptomatic vasospasm and subsequent DCI may benefit from endovascular or medical management strategies.

Stellate Ganglion Block and Intraarterial Spasmolysis in Patients with Cerebral Vasospasm: A Retrospective Cohort Study.

BACKGROUND: In patients with symptomatic cerebral vasospasm (CV) following aneurysmal subarachnoid hemorrhage who do not respond to medical therapy, urgent treatment escalation has been suggested to be beneficial for brain tissue at risk. In our routine clinical care setting, we implemented stellate ganglion block (SGB) as a rescue therapy with subsequent escalation to intraarterial spasmolysis (IAS) with milrinone for refractory CV. METHODS: In this retrospective analysis from 2012 to 2021, patients with CV following aneurysmal subarachnoid hemorrhage who received an SGB or IAS were identified. Patients were assessed through neurological examination and transcranial Doppler. Rescue therapy was performed in patients with mean cerebral blood flow velocity (CBFV) ≥ 120 cm/s and persistent neurological deterioration/intubation under induced hypertension. Patients were reassessed after therapy and the following day. The Glasgow Outcome Scale was assessed at discharge and 6-month follow-up. RESULTS: A total of 82 patients (mean age 50.16 years) with 184 areas treated with SGB and/or IAS met the inclusion criteria; 109 nonaffected areas were extracted as controls. The mean CBFV decrease in the middle cerebral artery on the following day was - 30.1 (± 45.2) cm/s with SGB and - 31.5 (± 45.2) cm/s with IAS. Mixed linear regression proved the significance of the treatment categories; other fixed effects (sex, age, aneurysm treatment modality [clipping or coiling], World Federation of Neurological Surgeons score, and Fisher score) were insignificant. In logistic regression, the presence of cerebral infarction on imaging before discharge from the intensive care unit (34/82) was significantly associated with unfavorable outcomes (Glasgow Outcome Scale ≤ 3) at follow-up. CONCLUSIONS: Stellate ganglion block and IAS decreased CBFV the following 24 h in patients with CV. We suggest SGB alone for patients with mild symptomatic CV (CBFV < 180 cm/s), while subsequent escalation to IAS proved to be beneficial in patients with refractory CV and severe CBFV elevation (CBFV ≥ 180 cm/s).

Management of perimesencephalic nonaneurysmal subarachnoid hemorrhage: a national survey.

Perimesencephalic nonaneurysmal subarachnoid hemorrhage (NASAH) is a rare type of subarachnoid hemorrhage (SAH), usually associated with minor complications compared to aneurysmal SAH. Up to date, data is scarce and consensus on therapeutic management and follow-up diagnostics of NASAH is often missing. This survey aims to evaluate the clinical management among neurosurgical departments in Germany. 135 neurosurgical departments in Germany received a hardcopy questionnaire. Encompassing three case vignettes with minor, moderate and severe NASAH on CT-scans and questions including the in-hospital treatment with initial observation, blood pressure (BP) management, cerebral vasospasm (CV) prophylaxis and the need for digital subtraction angiography (DSA). 80 departments (59.2%) answered the questionnaire. Whereof, centers with a higher caseload state an elevated complication rate (Chi2 < 0.001). Initial observation on the intensive care unit is performed in 51.3%; 47.5%, 70.0% in minor, moderate and severe NASAH, respectively. Invasive BP monitoring is performed more often in severe NASAH (52.5%, 55.0%, 71.3% minor, moderate, severe). CV prophylaxis and transcranial doppler ultrasound (TCD) are performed in 41.3%, 45.0%, 63.8% in minor, moderate and severe NASAH, respectively. Indication for a second DSA is set in the majority of centers, whereas after two negative ones, a third DSA is less often indicated (2nd: 66.2%, 72.5%, 86.2%; 3rd: 3.8%, 3.8%, 13.8% minor, moderate, severe). This study confirms the influence of bleeding severity on treatment and follow-up of NASAH patients. Additionally, the existing inconsistency of treatment pathways throughout Germany is highlighted. Therefore, we suggest to conceive new treatment guidelines including this finding.

Evaluation of DeGIR registry data on endovascular treatment of cerebral vasospasm in Germany 2018-2021: an overview of the current care situation. / Auswertung der DeGIR-Registerdaten zur endovaskulären Therapie von zerebralen Vasospasmen in Deutschland 2018­2021: Ein Überblick über die aktuelle Versorgungssituation.

BACKGROUND: Evaluation of endovascular therapies for cerebral vasospasm (CVS) documented in the DeGIR registry from 2018-2021 to analyse the current clinical care situation in Germany. METHODS: Retrospective analysis of the clinical and procedural data on endovascular spasm therapies (EST) documented anonymously in the DeGIR registry. We analysed: pre-interventional findings of CTP and consciousness; radiation dose applied, interventional-technical parameters (local medication, devices, angiographic result), post-interventional symptoms, complications and mortality. RESULTS: 3584 patients received a total of 7628 EST (median age/patient: 53 [range: 13-100, IQR: 44-60], 68.2 % women) in 91 (2018), 92 (2019), 100 (2020) and 98 (2021) centres; 5388 (70.6 %) anterior circulation and 378 (5 %) posterior circulation (both involved in 1862 cases [24.4 %]). EST was performed once in 2125 cases (27.9 %), with a mean of 2.1 EST/patient. In 7476 times, purely medicated EST were carried out (nimodipine: 6835, papaverine: 401, nitroglycerin: 62, other drug not specified: 239; combinations: 90). Microcatheter infusions were documented in 1132 times (14.8 %). Balloon angioplasty (BA) (additional) was performed in 756 EST (9.9 %), other mechanical recanalisations in 154 cases (2 %) and stenting in 176 of the EST (2.3 %). The median dose area product during ET was 4069 cGycm² (drug: 4002/[+]BA: 8003 [p < 0.001]). At least 1 complication occurred in 95 of all procedures (1.2 %) (drug: 1.1 %/[+]BA: 4.2 % [p < 0.001]). Mortality associated with EST was 0.2 % (n = 18). After EST, overall improvement or elimination of CVS was found in 94.2 % of cases (drug: 93.8 %/[+]BA: 98.1 % [p < 0.001]). In a comparison of the locally applied drugs, papaverine eliminated CVS more frequently than nimodipine (p = 0.001). CONCLUSION: EST have a moderate radiation exposure and can be performed with few complications. Purely medicated EST are predominantly performed, especially with nimodipine. With (additional) BA, radiation exposure, complication rates and angiographic results are higher or better. When considering drug EST alone, there is evidence for an advantage of papaverine over nimodipine, but a different group size has to be taken into account. In the analysis of EST, the DeGIR registry data are suitable for answering more specific questions, especially due to the large number of cases; for this purpose, further subgroupings should be sought in the data documentation. KEY POINTS: · In Germany, there are currently no guidelines for the endovascular treatment of cerebral vasospasm following spontaneous subarachnoid hemorrhage.. · In addition to oral nimodipine administration endovascular therapy is used to treat cerebral vasospasm in most hospitals.. · This is the first systematic evaluation of nationwide registry data on endovascular treatment of cerebral vasopasm in Germany.. · This real-world data shows that endovascular treatment for cerebral vasospasm has a moderate radiation exposure and can be performed with few complications overall. With (additional) balloon angioplasty, radiation exposure, complication rates and angiographic therapy results are higher or better.. CITATION FORMAT: · Neumann A, Weber W, Küchler J et al. Evaluation of DeGIR registry data on endovascular treatment of cerebral vasospasm in Germany 2018-2021: an overview of the current care situation. Fortschr Röntgenstr 2023; 195: 1018 - 1026.

Therapies for Delayed Cerebral Ischemia in Aneurysmal Subarachnoid Hemorrhage.

Delayed cerebral ischemia (DCI) is one of the most important complications of subarachnoid hemorrhage. Despite lack of prospective evidence, medical rescue interventions for DCI include hemodynamic augmentation using vasopressors or inotropes, with limited guidance on specific blood pressure and hemodynamic parameters. For DCI refractory to medical interventions, endovascular rescue therapies (ERTs), including intraarterial (IA) vasodilators and percutaneous transluminal balloon angioplasty, are the cornerstone of management. Although there are no randomized controlled trials assessing the efficacy of ERTs for DCI and their impact on subarachnoid hemorrhage outcomes, survey studies suggest that they are widely used in clinical practice with significant variability worldwide. IA vasodilators are first line ERTs, with better safety profiles and access to distal vasculature. The most commonly used IA vasodilators include calcium channel blockers, with milrinone gaining popularity in more recent publications. Balloon angioplasty achieves better vasodilation compared with IA vasodilators but is associated with higher risk of life-threatening vascular complications and is reserved for proximal severe refractory vasospasm. The existing literature on DCI rescue therapies is limited by small sample sizes, significant variability in patient populations, lack of standardized methodology, variable definitions of DCI, poorly reported outcomes, lack of long-term functional, cognitive, and patient-centered outcomes, and lack of control groups. Therefore, our current ability to interpret clinical results and make reliable recommendations regarding the use of rescue therapies is limited. This review summarizes existing literature on rescue therapies for DCI, provides practical guidance, and identifies future research needs.

Reversible cerebral vasoconstriction syndrome: A review of pathogenesis, clinical presentation, and treatment.

Reversible segmental narrowing of the intracranial arteries has been described since several decades in numerous clinical settings, using variable nosology. Twenty-one years ago, we tentatively proposed the unifying concept that these entities, based on similar clinical-imaging features, represented a single cerebrovascular syndrome. This "reversible cerebral vasoconstriction syndrome" or RCVS has now come of age. A new International Classification of Diseases code, (ICD-10, I67.841) has been established, enabling larger-scale studies. The RCVS2 scoring system provides high accuracy in confirming RCVS diagnosis and excluding mimics such as primary angiitis of the central nervous system. Several groups have characterized its clinical-imaging features. RCVS predominantly affects women. Recurrent worst-ever (thunderclap) headaches are typical at onset. While initial brain imaging is often normal, approximately one-third to half develop complications such as convexity subarachnoid hemorrhages, lobar hemorrhages, ischemic strokes located in arterial "watershed" territories and reversible edema, alone or in combination. Vasoconstriction evolves over hours to days, first affecting distal and then the more proximal arteries. An overlap between RCVS and primary thunderclap headache, posterior reversible encephalopathy syndrome, Takotsubo cardiomyopathy, transient global amnesia, and other conditions has been recognized. The pathophysiology remains largely unknown. Management is mostly symptomatic: headache relief with analgesics and oral calcium-channel blockers, removal of vasoconstrictive factors, and avoidance of glucocorticoids that can significantly worsen outcome. Intra-arterial vasodilator infusions provide variable success. Overall, 90-95% of admitted patients achieve complete or major resolution of symptoms and clinical deficits within days to weeks. Recurrence is exceptional, although 5% can later develop isolated thunderclap headaches with or without mild cerebral vasoconstriction.

Cervical Ganglion Sympathectomy to Treat Cerebral Vasospasm in Subarachnoid Hemorrhage.

Delayed cerebral ischemia (DCI) is still a significant cause of death and disability after aneurysmal subarachnoid hemorrhage. Cerebral vasospasm represents one of the most reported mechanisms associated with DCI. The management of DCI-related vasospasm remains a significant challenge for clinicians; induced hypertension, intraarterial vasodilators, and/or intracranial vessel angioplasty-particularly in refractory or recurrent cases-are the most used therapies. Because an essential role in the pathophysiology of cerebral vasospasm has been attributed to the adrenergic sympathetic nerves, a "sympatholytic" intervention, consisting of a temporary interruption of the sympathetic pathways using local anesthetics, has been advocated to minimize the vascular narrowing and reverse the consequences of cerebral vasospasm on tissue perfusion. In this review, we have analyzed the existing literature on the block of the cervical ganglions, particularly the stellate ganglion, in managing refractory cerebral vasospasm in patients with aneurysmal subarachnoid hemorrhage. These findings could help clinicians to understand the potential role of such intervention and to develop future interventional trials in this setting.