Bilateral Magnetic Resonance Imaging-Guided Focused Ultrasound Thalamotomy for Essential Tremor.

INTRODUCTION: Essential tremor is the most common movement disorder in adults. Bilateral symptoms are typical; however, bilateral thalamotomy for essential tremor is associated with a high probability of adverse events. We retrospectively investigated the efficacy and safety of staged bilateral ventral intermediate nucleus thalamotomy for refractory essential tremor using magnetic resonance imaging-guided focused ultrasound. METHODS: We enrolled 5 consecutive patients with refractory essential tremor between September 2016 and March 2020. Patients underwent a second operation at least 1 year after the first operation. The second lesion was created asymmetrically to the first lesion. RESULTS: Mean patient age was 57.6 years, and the mean interval between the 2 operations was 27.8 months. The second lesion center was superior to the first lesion in all patients. The mean baseline, second preoperative, and second postoperative Clinical Rating Scale for Tremor total scores were 63.6, 49.2, and 21.8, respectively. The mean baseline, second preoperative, and second postoperative Clinical Rating Scale for Tremor part C scores were 18.4, 8.2, and 2.6, respectively. One patient had permanent adverse events of slight dysarthria and discomfort in the tongue. No patient experienced dysphagia or cognitive dysfunction after the second operation. Four of the 5 patients were satisfied with the results of the bilateral treatment, including the patient who had permanent adverse events. CONCLUSIONS: Magnetic resonance imaging-guided focused ultrasound is an effective method for bilateral thalamotomy when adhering to the following considerations: (1) asymmetrical lesions are created and (2) sufficient interval (>1 year) between operations.

4-Hydroxyl-2-Nonenal Localized Expression Pattern in Retrieved Clots is Associated with Large Artery Atherosclerosis in Stroke Patients.

OBJECTIVES: The relationship between stroke etiology and clot pathology remains controversial. MATERIALS AND METHODS: We performed histological analysis of clots retrieved from 52 acute ischemic stroke patients using hematoxylin and eosin staining and immunohistochemistry (CD42b and oxidative/hypoxic stress markers). The correlations between clot composition and the stroke etiological group (i.e., cardioembolic, cryptogenic, or large artery atherosclerosis) were assessed. RESULTS: Of the 52 clots analyzed, there were no significant differences in histopathologic composition (e.g., white blood cells, red blood cells, fibrin, and platelets) between the 3 etiological groups (P = .92). By contrast, all large artery atherosclerosis clots showed a localized pattern with the oxidative stress marker 4-hydroxyl-2-nonenal (P < .01). From all 52 clots, 4-hydroxyl-2-nonenal expression patterns were localized in 28.8% of clots, diffuse in 57.7% of clots, and no signal in 13.5% of clots. CONCLUSIONS: A localized pattern of 4-hydroxyl-2-nonenal staining may be a novel and effective marker for large artery atherosclerosis (sensitivity 100%, specificity 82%).

Thrombolysis With Alteplase at 0.6 mg/kg for Stroke With Unknown Time of Onset: A Randomized Controlled Trial.

Background and Purpose- We assessed whether lower-dose alteplase at 0.6 mg/kg is efficacious and safe for acute fluid-attenuated inversion recovery-negative stroke with unknown time of onset. Methods- This was an investigator-initiated, multicenter, randomized, open-label, blinded-end point trial. Patients met the standard indication criteria for intravenous thrombolysis other than a time last-known-well >4.5 hours (eg, wake-up stroke). Patients were randomly assigned (1:1) to receive alteplase at 0.6 mg/kg or standard medical treatment if magnetic resonance imaging showed acute ischemic lesion on diffusion-weighted imaging and no marked corresponding hyperintensity on fluid-attenuated inversion recovery. The primary outcome was a favorable outcome (90-day modified Rankin Scale score of 0-1). Results- Following the early stop and positive results of the WAKE-UP trial (Efficacy and Safety of MRI-Based Thrombolysis in Wake-Up Stroke), this trial was prematurely terminated with 131 of the anticipated 300 patients (55 women; mean age, 74.4±12.2 years). Favorable outcome was comparable between the alteplase group (32/68, 47.1%) and the control group (28/58, 48.3%; relative risk [RR], 0.97 [95% CI, 0.68-1.41]; P=0.892). Symptomatic intracranial hemorrhage within 22 to 36 hours occurred in 1/71 and 0/60 (RR, infinity [95% CI, 0.06 to infinity]; P>0.999), respectively. Death at 90 days occurred in 2/71 and 2/60 (RR, 0.85 [95% CI, 0.06-12.58]; P>0.999), respectively. Conclusions- No difference in favorable outcome was seen between alteplase and control groups among patients with ischemic stroke with unknown time of onset. The safety of alteplase at 0.6 mg/kg was comparable to that of standard treatment. Early study termination precludes any definitive conclusions. Registration- URL: https://www.clinicaltrials.gov; Unique identifier: NCT02002325.

Catastrophic Multiple Microbleeds Caused by Infective Endocarditis Following Intravenous Thrombolysis and Endovascular Thrombectomy.

Ischemic stroke is one of the most common complications of infective endocarditis (IE). IE must be considered as one of the causes of acute ischemic stroke (AIS) with emergent large vessel occlusion (ELVO), but early diagnosis of IE is difficult. AIS with ELVO must be treated using endovascular thrombectomy (EVT), with or without intravenous thrombolysis (IVT). IVT for AIS due to IE is not well established and remains controversial because of the risk of intracranial hemorrhage. A 42-year-old man suffered from right hemiparesis and disorientation, and AIS with ELVO was diagnosed. EVT with IVT was successfully performed and recanalization was achieved, but catastrophic multiple cerebral microbleeds appeared after treatment. EVT without IVT could be chosen for AIS caused by IE to avoid hemorrhagic complications. Hypointense signal spots on T2*-weighted magnetic resonance imaging (MRI) and susceptibility-weighted MRI could facilitate early diagnosis of IE.

Improving Call-to-Door Time Using School-Based Intervention by Emergency Medical Technicians: The Akashi Project.

BACKGROUND: Identification of stroke signs by emergency medical technicians (EMTs) is important for initiating the "stroke chain of survival." The aim of the present study was to clarify the effect of EMT-led lessons on stroke awareness for schoolchildren in the Akashi project on the transportation time to arrive at the hospital. METHODS: Stroke lessons were given by EMTs to 887 elementary school children in elementary schools between September 2014 and October 2015. Data on transportation times from prehospital records and final diagnoses at discharge were collected from both pre- (period 1; January-June 2014) and posteducation (period 2; January-June 2016) periods. Transportation time or onset-to-door time was divided into two parts: the onset-to-call time and the call-to-door time. RESULTS: One hundred forty-four patients in period 1 and 143 in period 2 were transported with potential strokes identified by EMTs. Among these, 119 (83%) in period 1 and 114 (80%) in period 2 had final diagnosis of stroke or transient ischemic attack. The mean age in period 2 was older than that in period 1 (75 years old versus 72 years old); however, there were no significant differences in gender and consciousness level between the 2 periods. The median call-to-door time of 28 minutes for period-2 patients was significantly shorter than that for period-1 patients (32 minutes, P = .0057). There were no differences in median onset-to-door times and onset-to-call times between the 2 periods. CONCLUSIONS: School-based education about stroke conducted by EMTs may be a promising strategy to cut the prehospital delay and to widely spread stroke awareness via school children and EMTs.

Spreading Awareness of Stroke through School-Based Education: A Pooled Analysis of Three Community-Based Studies.

BACKGROUND: Advancing school-based education is a promising means to spread knowledge pertaining to stroke. The aim of the current study was to clarify whether stroke lessons provided by schoolteachers could deliver stroke knowledge to children (aged 9-11 years) and their parents, at a similar level to when taught by medical staff. METHODS: Schoolteachers conducted lessons on stroke for school children using the educational materials we prepared (i.e., the teacher group; 1051 children and 719 parents). This was compared with our previous data from Akashi city and Tochigi prefecture, in which the stroke lessons were conducted by medical staff (i.e., the medical group; 1031 children and 756 parents). Three campaigns were conducted between September 2014 and May 2016. Each child was given education materials to take home to discuss stroke with their parents. The children and their parents answered questionnaires on stroke knowledge, at baseline, immediately after the lesson, and at 3 months after the lesson. RESULTS: Compared with the time point before the lesson, both children and parents instructed by the teacher group showed significant increases in the scores about stroke symptoms and risk factors, immediately and at 3 months after the lesson (P < .001). The combined analysis for the group instructed by medical personnel showed no significant differences in the stroke knowledge scores between the 2 groups at 3 months. CONCLUSIONS: Teacher-led lessons, using our educational material, adequately delivered knowledge of stroke to children and parents, in a manner that was similar to when medical staff delivered this information.

Studies on the biosynthesis of ralfuranones in Ralstonia solanacearum.

Ralfuranones, aryl-furanone secondary metabolites, are involved in the virulence of Ralstonia solanacearum in solanaceous plants. Ralfuranone I (6) has been suggested as a biosynthetic precursor for other ralfuranones; however, this conversion has not been confirmed. We herein investigate the biosynthesis of ralfuranones using feeding experiments with ralfuranone I (6) and its putative metabolite, ralfuranone B (2). The results obtained demonstrated that the biosynthesis of ralfuranones proceeded in enzymatic and non-enzymatic manners.

Methyl 3-Hydroxymyristate, a Diffusible Signal Mediating phc Quorum Sensing in Ralstonia solanacearum.

Ralstonia solanacearum, a plant pathogenic bacterium causing "bacterial wilt" on crops, uses a quorum sensing (QS) system consisting of phc regulatory elements to control its virulence. Methyl 3-hydroxypalmitate (3-OH PAME) was previously identified as the QS signal in strain AW1. However, 3-OH PAME has not been reportedly detected from any other strains, and this suggests that they produce another unknown QS signal. Here we identify (R)-methyl 3-hydroxymyristate [(R)-3-OH MAME] as a new QS signal that regulates the production of virulence factors and secondary metabolites. (R)-3-OH MAME was synthesized by the methyltransferase PhcB and sensed by the histidine kinase PhcS. The phylogenetic trees of these proteins from R. solanacearum strains were divided into two groups, according to their QS signal types--(R)-3-OH MAME or (R)-3-OH PAME. These results demonstrate that (R)-3-OH MAME is another crucial QS signal and highlight the unique evolution of QS systems in R. solanacearum.

Involvement of ralfuranone production in the virulence of Ralstonia solanacearum OE1-1.

Ralstonia solanacearum causes a destructive disease called "bacterial wilt" in numerous plant species. Its virulence is controlled by the transcriptional regulator PhcA, the activity of which is, in turn, regulated in a cell-density dependent manner, termed quorum sensing. We herein described the identification and characterization of ralfuranones J-L, new PhcA-regulated secondary metabolites, and the known derivatives, ralfuranones A and B, from R. solanacearum strain OE1-1. Their structures were determined by spectroscopic and chemical methods. These ralfuranones were also detected in vascular exudates from host plants infected with OE1-1. Deletion of ralA, which encodes an enzyme for ralfuranone biosynthesis, reduced the virulence of OE1-1 in tomato plants. Virulence was restored by complementation of the ralA gene. The results suggest that ralfuranones play important roles in the virulence of OE1-1.

Coil Embolization of Unruptured Distal Anterior Cerebral Artery Aneurysm Using a Marathon Microcatheter.

Marathon is rarely used in coil embolization for an aneurysm; particularly, there have been no reports about distal anterior cerebral artery aneurysms. We have reported a case of successful use of Marathon in coil embolization in case of a distal anterior cerebral artery aneurysm. The patient was an 83-year-old woman. She had undergone coil embolization for an unruptured distal anterior cerebral artery aneurysm, which was discovered by chance. Our initial approach involved the use of a combination of Traxcess and Excelsior SL-10, but the use of SL-10 could not follow Traxcess because the right anterior cerebral artery from the right internal carotid artery had a sharp bifurcation. However, by switching to a combination of TENROU and Marathon, we could access the aneurysm. We thereby decided to continue the use of Marathon in order to complete the coil embolization. In coil embolization for an aneurysm, Marathon was found to be useful, depending on the location of the aneurysm and access route.

Decline in the Incidence of Chronic Subdural Hematoma During the Coronavirus Disease 2019 Pandemic: A Retrospective Single-Center Descriptive Study.

The coronavirus disease 2019 (COVID-19) pandemic has forced restrictions on social activities in some areas. There has also been a decrease in the number of trauma patients in the United States during the COVID-19 pandemic. Chronic subdural hematoma (CSDH) is a traumatic disorder that often develops following head injury. We therefore investigated the impact of the COVID-19 pandemic on CSDH. In this retrospective single-center descriptive study from April 2018 through September 2021, there were 5,282 head trauma patients and 196 patients with CSDH in the pre-pandemic group compared to 4,459 head trauma patients and 140 patients with CSDH in the intra-pandemic group. Significant decreases in the incidence rate (IR) of head trauma (951/100,000 vs. 795/100,000 person-years; IR ratio (IRR): 0.836, 95% confidence interval (CI): 0.803-0.870, p < 0.001) and also in the IR of CSDH (35.0/100,000 vs. 24.8/100,000 person-years, IRR: 0.708, 95% CI: 0.570-0.879, p = 0.002) were seen in the intra-pandemic group compared to the pre-pandemic group. In this study, the COVID-19 pandemic was associated with significant decreases in the IRs of head trauma and CSDH due to forced restrictions on social activities. Besides, the IR of mild cases of CSDH was significantly lower in the intra-pandemic group than in the pre-pandemic group (IRR: 0.68, 95% CI: 0.51-0.89, p = 0.006). Fewer people being out in communities should result in fewer chances for head trauma and CSDH. On the other hand, forced restrictions on social activities due to the COVID-19 pandemic should aggravate CSDH.

Mechanical thrombectomy in acute stroke for superior limb of the fenestration of the middle cerebral artery.

Fenestration of the middle cerebral artery (MCA) is a rare anatomic variant, and lenticulostriate arteries (LSAs) often arise from the superior limb of the fenestrated segment. A case of acute occlusion of the superior limb of a fenestrated MCA that successfully underwent mechanical thrombectomy is presented. Digital subtraction angiography performed for a 73-year-old man with acute left hemiparesis showed poor visualization of the upper half of the right M1 segment with maintenance of antegrade peripheral circulation of the MCA territory, and mechanical thrombectomy was successfully performed using a stent retriever with intravenous thrombolysis. After restoration of the MCA, the vascular variant of a fenestrated MCA was found. Clinicians must consider the possibility of acute occlusion of a fenestrated MCA before endovascular thrombectomy. Restoration of acute occlusion of the upper limb of a fenestrated MCA can avoid LSA territory infarction.

Staged strategy using a transcarotid approach for acute tandem occlusions with left common carotid artery origin steno-occlusive lesion.

BACKGROUND: Endovascular treatment for acute tandem occlusion (ATO) of the combination of an ipsilateral extracranial internal carotid artery (ICA) steno-occlusive lesion with concurrent intracranial artery occlusion is challenging. Whether extracranial lesions, especially in cases of the left common carotid artery (LCCA) origin steno-occlusive lesions, should be treated after recanalization of an occluded intracranial artery by mechanical thrombectomy simultaneously in the same session has not been established. We report two cases of successful ATO with LCCA origin steno-occlusive lesions treated by staged retrograde transcarotid LCCA stenting followed emergent mechanical thrombectomy in two sessions because of the tortuous aortic arch. CASE DESCRIPTION: A 61-year-old man with left ICA occlusion and an 82-year-old woman with left middle cerebral artery occlusion underwent emergent mechanical thrombectomy for ATO with LCCA origin stenoocclusive lesions. We achieved recanalization of large vessels, but severe stenosis of LCCAs remained. Because of the tortuous aortic arch, we decided to treat LCCA origin steno-occlusive lesions with staged stenting in the other session followed emergent mechanical thrombectomy. Postoperative courses were uneventful, and their symptoms improved. We performed stenting using a transcarotid approach through CCA cut down for LCCA steno-occlusive lesions without any complications. CONCLUSION: The staged strategy leaving LCCA origin stenosis seems to offer a better strategy than the simultaneous strategy for ATO with LCCA origin steno-occlusive lesions. A retrograde transcarotid approach through CCA cut down is recommended for LCCA stenting.

A case of recurrent cavernous sinus dural arteriovenous fistula arising after superselective shunt occlusion and detected by venous arterial spin labeling.

BACKGROUND: Superselective shunt occlusion (SSSO) for cavernous sinus dural arteriovenous fistula (CSDAVF) avoids the risk of cranial nerve palsy, unlike entire sinus packing, but requires paying attention to recurrence. Distinguishing between true and paradoxical worsening of postoperative ophthalmic symptoms using a less-invasive modality is often difficult. Here, we report a case of true worsening of neuro-ophthalmic symptom by recurrent CSDAVF detected by venous-arterial spin labeling (ASL) on magnetic resonance imaging. CASE DESCRIPTION: A 55-year-old woman with neither contributory medical history nor previous head trauma presented with neuro-ophthalmic symptoms and pulsatile tinnitus. Digital subtraction angiography (DSA) revealed CSDAVF with multiple shunted pouches. She underwent successful transvenous SSSO, but neuroophthalmic symptom worsened after SSSO and venous-ASL revealed increased signal intensity in the right superior orbital vein (SOV). DSA confirmed recurrent CSDAVF and additional transvenous embolization was performed. Neuro-ophthalmic symptoms and venous-ASL hyperintensity on SOV improved postoperatively. CONCLUSION: Venous-ASL is noninvasive and seems useful for detecting true worsening of neuro-ophthalmic symptoms of recurrent CSDAVF.

Focused Ultrasound Thalamotomy for Refractory Essential Tremor: A Japanese Multicenter Single-Arm Study.

BACKGROUND: Several feasibility studies and a randomized, controlled, multicenter trial have demonstrated the safety and efficacy of unilateral transcranial magnetic resonance-guided focused ultrasound (FUS) lesioning of the ventral intermediate thalamic nucleus in treating essential tremor. OBJECTIVE: To evaluate the safety and efficacy of FUS thalamotomy in a Japanese patient cohort through a prospective, multicenter, single-arm confirmatory trial. METHODS: A total of 35 patients with disabling refractory essential tremor underwent unilateral FUS thalamotomy and were followed up for 12 post-treatment months. Safety was measured as the incidence and severity of treatment-related adverse events. Efficacy was measured as the tremor severity and quality of life improvements using the Clinical Rating Scale for Tremor and Questionnaire for Essential Tremor. RESULTS: The mean skull density ratio (SDR) was 0.47. There was a significant decrease in the mean postural tremor score of the treated hand from baseline to 12 mo by 56.4% (95% CI: 46.7%-66.1%; P < .001), which was maintained at last follow-up. Quality of life improved by 46.3% (mean overall Questionnaire for Essential Tremor score of 17.4 [95% CI: 12.1-22.7]) and there were no severe adverse events. The most frequent adverse event was gait disturbance and all events resolved. CONCLUSION: Unilateral FUS thalamotomy allowed significant and sustained tremor relief and improved the quality of life with an outstanding safety profile. The observed safety and efficacy of FUS thalamotomy were comparable to those reported in a previous multicenter study with a low SDR, and inclusion of the low SDR group did not affect effectiveness.

Platelet function and spontaneous thrombolytic activity of patients with cerebral infarction assessed by the global thrombosis test.

Measurements of platelet reactivity and assessment of the efficacy of antiplatelet drugs are widely recognized as pre-requisite for the diagnosis and treatment of stroke patients. A recently established shear-induced platelet reactivity test using non-anticoagulated blood (the Global Thrombosis Test) has facilitated measurements of physiologically relevant platelet function and thrombolytic activity. 195 healthy volunteers, not taking antiplatelet drugs or anticoagulants, and 185 patients with acute cerebrovascular diseases were enrolled. The effect of antiplatelet drugs on platelet function and thrombolytic activity was assessed using the Global Thrombosis Test after 14 days of medication. The occlusion time (OT), an index of platelet reactivity, in healthy controls was 284.9 ± 92.2 s. The lysis time (LT), an index of thrombolytic activity, in healthy controls was 2,231 ± 1,223 s. Both times had no significant difference between males and females. The OT of all stroke patients was 210.3 ± 140.8 s and was shorter than that of the healthy controls (284.9 ± 92.2, p < 0.0001). The LT of all stroke patients was 3,159 ± 1,549 s and was longer than that of the controls (2,231 ± 1,223, p < 0.0001). Medication significantly prolonged the OT from 184.5 ± 150.6 s (before) to 295.3 ± 208.1 s (after) in all patients, indicating a reversal of the hyper-platelet reactivity. In addition, medication shortened the LT from 3,924 ± 1,718 s (before) to 3,107 ± 1,794 s (after) in all patients. A prothrombotic state exists in stroke patients due to enhanced platelet function and suppressed thrombolytic activity. Medication improved these physiological parameters of haemostasis.

What factors impact the clinical outcome of magnetic resonance imaging-guided focused ultrasound thalamotomy for essential tremor?

OBJECTIVE: Magnetic resonance imaging-guided focused ultrasound (MRgFUS) is a novel and useful treatment for essential tremor (ET); however, the factors impacting treatment outcome are unknown. The authors conducted this study to determine the factors affecting the outcome of MRgFUS. METHODS: From May 2016 through August 2017, 15 patients with ET were admitted to Ohnishi Neurological Center and treated with MRgFUS. To determine the factors impacting treatment outcome, the authors retrospectively studied correlations between the Clinical Rating Scale for Tremor (CRST) improvement rate and age, disease duration, baseline CRST score, skull density ratio (SDR), skull volume, maximum delivered energy, or maximum temperature. RESULTS: The mean CRST score was 18.5 ± 5.8 at baseline and 4.6 ± 5.7 at 1 year. The rate of improvement in the CRST score was 80% ± 22%. Younger age and lower baseline CRST score were correlated with a higher CRST improvement rate (p = 0.025 and 0.007, respectively). To obtain a CRST improvement rate ≥ 50%, a maximum temperature ≥ 55°C was necessary. There was no correlation between SDR and CRST improvement rate (p = 0.658). A lower SDR and higher skull volume required significantly higher maximum delivered energy (p = 0.014 and 0.016, respectively). A higher maximum temperature was associated with a significantly larger lesion volume (p = 0.026). CONCLUSIONS: Younger age and lower baseline CRST score were favorable outcome factors. It is important to assess predictive factors when applying MRgFUS.

A thread of hope for successful revascularization for acute embolic basilar artery occlusion due to miserable vertebral artery stump syndrome. A technical report.

Acute basilar artery occlusion (BAO) is associated with major morbidities and a high mortality rate. The prevalence of acute BAO is 10.4% among patients treated with thrombectomy for acute large vessel occlusion. Vertebral artery stump syndrome (VASS) reportedly causes ischemic stroke with tandem occlusions as vertebral artery (VA) origin occlusion and BAO. The pathogenesis of ischemic stroke due to VASS can be attributed to thrombi or emboli. Acute embolic BAO due to VASS accounted for 2 of 25 cases (8.0%) of BAO treated using thrombectomy between April 2014 and May 2019 in our registry. VASS must be considered as one cause of BAO. With the initial Magnetic resonance angiography on arrival, it is difficult to distinguish between BAO due to simple cardiogenic embolus and due to embolus caused by VASS rapidly. In patients suffering from acute embolic BAO due to VASS, the presence of VA origin occlusion makes endovascular therapy (EVT) difficult to perform. Here, we report consecutive cases of thrombectomy for acute embolic BAO due to VASS, showing markedly different outcomes. VA origin occlusion severely limits the technical options for EVT. Visualization or conjecture of the origin of both or dominant VAs conceivably offers the possibility of successful EVT and may allow good outcomes.

Predictors of Outcomes After Focused Ultrasound Thalamotomy.

BACKGROUND: Magnetic resonance-guided focused ultrasound thalamotomy (FUS-T) is an emerging treatment for essential tremor (ET). OBJECTIVE: To determine the predictors of outcomes after FUS-T. METHODS: Two treatment groups were analyzed: 75 ET patients enrolled in the pivotal trial, between 2013 and 2015; and 114 patients enrolled in the postpivotal trials, between 2015 and 2016. All patients had medication-refractory, disabling ET, and underwent unilateral FUS-T. The primary outcome (hand tremor score, 32-point scale with higher scores indicating worse tremor) and the secondary outcome variables (Clinical Rating Scale for Tremor Part C score: 32-point scale with higher scores indicating more disability) were assessed at baseline and 1, 3, 6, and 12 mo. The operative outcome variables (ie, peak temperature, number of sonications) were analyzed. The results between the 2 treatment groups, pivotal and postpivotal, were compared with repeated measures analysis of variance and adjusted for confounding variables. RESULTS: A total of 179 patients completed the 12-mo evaluation. The significant predictors of tremor outcomes were patient age, disease duration, peak temperature, and number of sonications. A greater improvement in hand tremor scores was observed in the postpivotal group at all time points, including 12 mo (61.9% ± 24.9% vs 52.1% ± 24.9%, P = .009). In the postpivotal group, higher energy was used, resulting in higher peak temperatures (56.7 ± 2.5 vs 55.6 ± 2.8°C, P = .004). After adjusting for age, years of disease, number of sonications, and maximum temperature, the treatment group was a significant predictor of outcomes (F = 7.9 [1,165], P = .005). CONCLUSION: We observed an improvement in outcomes in the postpivotal group compared to the pivotal group potentially reflecting a learning curve with FUS-T. The other associations of tremor outcomes included patient age, disease duration, peak temperature, and number of sonications.

Transient Augmentation of Intraoperative Motor Evoked Potentials During Middle Cerebral Artery Aneurysm Surgery.

OBJECTIVE: To study clinical significance of augmentation of intraoperative motor evoked potentials (MEPs) during direct open surgery for middle cerebral artery (MCA) aneurysms. METHODS: Between 2009 and 2017, 134 MCA aneurysm surgeries were performed with intraoperative MEP monitoring. The frequency and cause of augmentation with >50% increase of MEP amplitude from baseline were studied. Factors associated with MEP augmentation were investigated. RESULTS: MEP augmentation was demonstrated in 9 patients. All 9 events were observed just after application of the temporary clip to the parent artery. The ratio of the maximum amplitude to baseline was 2.6 ± 1.1 at an mean of 2.4 ± 1.1 minutes after parent artery occlusion. Ten patients who did not show MEP augmentation after parent artery occlusion were compared with the patients showing MEP augmentation. The distance of the temporary clip point from the midline was smaller in patients with MEP augmentation compared with patients without MEP augmentation (P = 0.033). CONCLUSIONS: MEP augmentation was thought to be an early ischemic sign preceding a significant decrease in MEPs during MCA aneurysm surgery. Transient augmentation of MEPs was more frequently observed in cases with a temporary clip applied to the more proximal part of the MCA.