The impact of hormonal dynamics and serum sodium fluctuations on symptomatic vasospasm after subarachnoid hemorrhage.

BACKGROUND: Symptomatic vasospasm (SVS) is a major cause of morbidity and mortality in aneurysmal subarachnoid hemorrhage (SAH), and serum sodium frequently decreases before SVS. Serum sodium changes might be regulated by sodium metabolism-related hormones. This multi-institutional prospective cohort study therefore investigated the measurement of sodium metabolism-related hormones to elucidate the pathophysiology of serum sodium changes in SAH. METHODS: SAH patients were treated with clipping or coiling from September 2017 to August 2020 at five hospitals. The laboratory data of 133 SAH patients were collected over 14 days and correlations between changes in serum sodium, sodium metabolism-related hormones (plasma adrenocorticotropic hormone (ACTH), serum cortisol, plasma arginine vasopressin (AVP)), and SVS were determined. Serum sodium concentrations were measured every day and serum sodium levels >135 mEq/L were maintained until day 14. RESULTS: Of the 133 patients, 18 developed SVS within 14 days of subarachnoid hemorrhage onset (SVS group) and 115 did not suffer from SVS (non-SVS group). Circulating AVP, ACTH, and cortisol concentrations were significantly higher on day 1 in the SVS group compared with the non-SVS group. Fluctuations in serum sodium in the SVS group were significantly higher than those in the non-SVS group. There were antiparallel fluctuations in serum sodium and potassium from days 2 to 14. CONCLUSIONS: Elevated levels of ACTH/cortisol and AVP on day 1 may be predictive markers for the occurrence of SVS. Multiple logistic regression analysis showed that serum sodium fluctuations were associated with SVS occurrence. Serum sodium fluctuations were associated with stress-related hormonal dynamics. (249 words).

An Aneurysm at the Origin of a Duplicated Middle Cerebral Artery Treated by Stent-Assisted Coiling Using the "Wrapped-Candy" Low-Profile Visualized Intraluminal Support (LVIS) Technique: A Technical Case Report and Review of the Literature.

BACKGROUND: Aneurysms at the origin of a duplicated middle cerebral artery (DMCA) are quite rare. Here, we report a patient with such an aneurysm successfully treated endovascularly using our novel "wrapped-candy" low-profile visualized intraluminal support (LVIS) technique. CASE DESCRIPTION: A 44-year-old woman underwent endovascular treatment for an unruptured wide-necked aneurysm at the origin of a DMCA that incorporated the origin of the DMCA into its neck. Stent-assisted coiling was performed using our newly developed "wrapped-candy" LVIS technique. To protect the origin of the DMCA and increase the stent metal density at the neck, an LVIS blue 3.5-mm × 22-mm stent was deployed by pushing the delivery wire aggressively to transform the visible wire components of the LVIS into a shape like "wrapped candy," maximizing the strut compaction at the neck of the aneurysm. Subsequently, the aneurysm component was coiled using a jailed microcatheter. The final procedural angiography demonstrated almost complete aneurysm occlusion with DMCA preservation. CONCLUSIONS: Stent-assisted coiling can be a feasible treatment for an unruptured, usually wide-necked, aneurysm at the origin of a DMCA. The wrapped-candy LVIS technique may be useful in more challenging morphologies such as wide-necked aneurysms that incorporate the branch origin into the aneurysm neck.

Double Stent Retriever (SR) Technique: A Novel Mechanical Thrombectomy Technique to Facilitate the Device-Clot Interaction for Refractory Acute Cerebral Large Vessel Occlusions.

BACKGROUND: Mechanical thrombectomy has become the standard treatment for acute ischemic stroke caused by large vessel occlusion; however, refractory occlusions still occur despite various thrombectomy procedures. The double stent retriever (SR) technique, which employs 2 SRs simultaneously at the occlusion, can be useful for such refractory occlusions. METHODS: We described 2 cases of refractory acute cerebral occlusion despite the use of conventional thrombectomy procedures that were both treated with the double SR technique. To discuss the technical aspects of how this easy-to-perform technique facilitates the device-clot interaction, we also evaluated radiographic findings of the SR strut during the procedure. RESULTS: In both cases, conventional thrombectomy procedures, including an SR alone, an aspiration catheter alone, and combined use of the SR and aspiration catheter, failed to recanalize the occlusion. The double SR technique was then performed with the stent-in-stent method in 1 patient and the parallel stent method in 1 patient. One pass of this technique retrieved hard clots and successfully recanalized the refractory occlusion in both cases. Intraprocedural radiographic images of these cases showed that the degree of stent expansion improved after deployment of the second SR compared with the first SR. CONCLUSIONS: Our radiographic findings suggested that adding a second SR facilitates the device-clot interaction at the occlusion site. The double SR technique may be an easy-to-perform thrombectomy technique to improve clot-capturing ability for the management of refractory acute cerebral artery occlusions.

Impact of Additional Lipid-Lowering Therapy on New Ischemic Lesions of Diffusion-Weighted Imaging in Carotid Artery Stenting.

BACKGROUND: New ischemic lesions on diffusion-weighted imaging (DWI) are frequently found after carotid artery stenting (CAS) and sometimes cause neurologic deficit. We investigated the rate and the potential factor of new DWI lesions during the perioperative period of CAS in symptomatic patients at our institution. MATERIALS AND METHODS: Of 187 consecutive patients who underwent CAS (April 2013-August 2016), we investigated 60 symptomatic patients with artery-to-artery embolism from carotid plaque. During hospitalization for ischemic stroke, patients with more than 120 mg/dL of plasma low-density lipoprotein cholesterol (LDL-C) level or more than 100 mg/dL of LDL-C level in case of coronary artery disease were administered additional lipid-lowering therapy (ALL therapy), for example, the same statin as patients took or evolocumab for patients with the maximum tolerated dose of statin. All patients were implanted the same type of carotid stent by the same procedure as we predefined. We implemented data analysis to identify factors on new DWI lesions. RESULTS: New DWI lesions were observed in 17 patients (28%). Baseline plasma triglyceride level was found to be the factor of new DWI lesions. ALL therapy was administered to 26 patients, including 8 patients of evolocumab. The average period from the start of ALL therapy to CAS was 15 days. New DWI lesions occurred in 11.5% of patients with ALL therapy and 41.2% of patients without ALL therapy (P = .019). Multivariate logistic analysis showed that ALL therapy was an independent predictor of absence of new DWI lesions (P = .029). CONCLUSIONS: ALL therapy before CAS may reduce new DWI lesions.

Decreased serum sodium levels predict symptomatic vasospasm in patients with subarachnoid hemorrhage.

BACKGROUND: Symptomatic vasospasm is a major cause of morbidity and mortality in subarachnoid hemorrhage patients. Hyponatremia and dehydration due to natriuresis after subarachnoid hemorrhage are related to symptomatic vasospasm. Therefore, most institutions are currently targeting euvolemia and eunatremia in subarachnoid hemorrhage patients to avoid complications. We retrospectively investigated the predictors of symptomatic vasospasm with respect to water and sodium homeostasis, while maintaining euvolemia and eunatremia after subarachnoid hemorrhage. METHODS: We monitored changes in serum sodium levels, serum osmolarity, daily sodium intake, daily urine volume, and daily water balance for 14days after subarachnoid hemorrhage. Outcomes were assessed using the modified Rankin scale at 1month after subarachnoid hemorrhage. RESULTS: Among 97 patients, 27 (27.8%) had symptomatic vasospasm. Patients with symptomatic vasospasm were older than those without symptomatic vasospasm; the occurrence of symptomatic vasospasm affected outcomes. Serum sodium levels were sequentially significantly decreased, but within the normal range from 1day before the occurrence of symptomatic vasospasm. Serum osmolarity of the spasm group was lower than that of the non-spasm group. CONCLUSIONS: Symptomatic vasospasm occurs more often in older patients and affects outcomes. A decrease in serum sodium levels occurs a day before symptomatic vasospasm. This observation may help predict symptomatic vasospasm.

Significance of blood aspiration in carotid artery stenting with Angioguard XP.

BACKGROUND AND PURPOSE: In some patients, angiographic flow impairment is observed during carotid artery stenting (CAS) using Angioguard XP (AGXP), resulting in neurological symptoms. CAS was thus modified to improve clinical outcome. METHODS: Ninety-seven patients were treated with CAS using AGXP from January 2008 to October 2009. In period I (January-December 2008; n = 53), blood aspirations were performed only in no-flow cases. In period II (January-October 2009; n = 44), blood aspirations were performed in no-flow and slow-flow cases. Clinical outcome, detection of microembolic lesions on diffusion-weighted imaging (DWI) and flow impairment during CAS were examined between these two periods before and after modifying the CAS procedure. RESULTS: Periprocedural transient ischemic attacks occurred in 10 patients (18.9%) and one patient (2.27%) in periods I and II, respectively (P = .018). Minor and major strokes were observed in two patients in each period (P = .849). New ipsilateral DWI lesions were detected in 25 patients (47.2%) and 11 patients (25.0%) in periods I and II, respectively (P = .024). Among 18 slow-flow cases, new DWI lesions were detected in one patient (9.09%) and five patients (71.4%) with (n = 11) and without (n = 7) blood aspirations, respectively (P = .013). Neurological symptoms were observed only in three of seven patients (42.9%) without aspirations, compared to one of 11 patients (9.1%) with aspirations (P = .043). CONCLUSION: Postoperative symptomatic stroke and new DWI lesions are significantly associated with blood flow impairment during CAS using AGXP. When flow impairment occurs, blood aspiration should be performed.

Carotid artery occlusion and collateral circulation in C57Black/6J mice detected by synchrotron radiation microangiography.

Using monochromatic synchrotron radiation, we performed microangiography in C57BL/6J mice and investigated their vasculature after unilateral and bilateral carotid artery occlusion. Bilateral occlusion of the carotid artery was made by a ligation of the left common carotid artery followed by a ligation of the right internal carotid artery (ICA) two days later (n=12). Five days after the second surgery, angiography was performed. Unilateral occlusion was made by clipping the right ICA and then angiography was performed immediately (n=5). The control mice did not undergo any occlusion (n=5). We removed the brain of the bilateral occlusion mice after angiography and examined the infarction area. The cerebral microvessels in all animals were clearly visualized. In the control mice, the posterior communicating artery (Pcom) was not visualized. In the unilateral occlusion mice, the anastomosis of the pterygopalatine artery (PPA) and the external carotid artery (ECA) were recognized. The PPA is thus considered to play a role in the collateral vessel between the ICA and the ECA. The Pcom was not visualized. In the bilateral occlusion mice, the Pcom was observed either unilaterally (n=5) or bilaterally (n=5). The Pcom supplied blood flow to the anterior circulation from the vertebrobasilar arteries. The bilateral occlusion mice that had at least one visualized Pcom did not have any infarction. We could successfully visualize the cerebral vasculature of normal mice and carotid artery occluded mice in an in vivo study. Microangiography can demonstrate the development of vasculature and the blood flow dynamics in mice.

Sca-1 and Thy-1 accelerate neuron-like differentiation in bone marrow stromal cells.

Bone marrow stromal cells taken from EGFP transgenic mice were sorted by magnetic beads with surface markers for Sca-1 and Thy-1. The cells were then co-cultured on organotypic hippocampal slice or with neuronal cell feeder in dish. On hippocampus, both Sca-1 and Thy-1 positive cells showed 4- 8 folds higher potential to show neuron-like morphology than negative cells. In dish, negative cells fewly survived but each positive cells survived and showed neuron-like differentiation. In both culture condition, retinoic acid supplement accelerate differentiation. Differentiated Sca-1 and Thy-1 positive cells were immunohistochemically GFAP- and NeuN-negative but nestin-, neurofilament- and NSE-positive. Neuron-like differentiation of bone marrow cells can be enhanced by selection using cell surface proteins.

In vivo X-ray angiography in the mouse brain using synchrotron radiation.

BACKGROUND AND PURPOSE: We, for the first time, performed in vivo x-ray angiography in the mouse brain using SPring-8, a third-generation synchrotron radiation facility. METHODS: A thin PE-50 tube was placed in the unilateral external carotid artery in adult male C57BL/6J mice. While maintaining the blood flow in the internal carotid artery, 33 muL of contrast agent was injected and then selective angiography of the hemisphere was performed. RESULTS: The average diameters of cerebral artery were as follows: 142.5+/-7.90 microm in middle cerebral artery, 138.3+/-9.35 microm in anterior cerebral artery, 120.5+/-5.53 microm in posterior cerebral artery, and 162.6+/-10.87 microm in internal carotid artery (n=5). To demonstrate the changes in diameter, we induced hypercapnia and detected the dilatation of the vessels between 121% and 124% of the original diameters (n=5). We also repeated angiography in the mice before and after intracarotid injection of vasodilatation drugs papaverine hydrochloride, ATP disodium, and fasudil hydrochloride hydrate and demonstrated the chronological changes in the diameters in each artery at 1, 5, 15, and 30 minutes after injection (n=1 for each drug). CONCLUSIONS: Using only a minimum volume of the contrast agent, synchrotron radiation enables us to study x-ray angiography in the mouse brain. The morphology of the vessels can be clearly observed under physiological conditions. The diameters and their changes can also be successfully studied in vivo.