Vessel Occlusion Research Articles

Utility of automated CT perfusion software in acute ischemic stroke with large and medium vessel occlusion.

Early diagnosis of large vessel occlusion (LVO) in acute stroke often requires CT angiography (CTA). Automated CT perfusion (CTP) software, which identifies blood flow abnormalities, enhances LVO diagnosis and patient selection for endovascular thrombectomy (EVT). This study evaluates the sensitivity of automated CTP images in detecting perfusion abnormalities in patients with acute ischemic stroke (AIS) and LVO or medium vessel occlusion (MeVO), compared to CTA. We screened acute ischemic stroke patients presenting within 24 h who underwent CT, CTA, and CTP as per institutional protocol. RAPID AI software processed CTP images, while neuroradiologists reviewed CTA for intracranial arterial occlusions. Sensitivity, specificity, and accuracy of automated CTP maps in detecting occlusions were assessed. Of 790 screened patients, 31 were excluded due to lack of RAPID CTP data or poor-quality scans, leaving 759 for analysis. The median age was 71 years (IQR: 61-81), with 47% female. Among them, 678 had AIS, and 81 had AIS ruled out. CTA identified arterial occlusion in 562 patients (74%), with corresponding CTP abnormalities in 537 patients (Tmax > 6 sec). In the 197 without occlusion, CTP was negative in 161. Automated CTP maps had a sensitivity of 95.55% (CI 95: 93.50-97.10%), specificity of 81.73% (CI 95: 75.61-86.86%), negative predictive value of 98.22% (CI 95: 97.39-98.79%), positive predictive value of 63.54% (CI 95: 56.46-70.09%), and overall accuracy of 85.18% (CI 95: 82.45-87.64%). Automated CTP maps demonstrated high sensitivity and negative predictive value for LVOs and MeVOs, suggesting their usefulness as a rapid diagnostic tool, especially in settings without expert neuroradiologists.

Large ischemic core defined by visually assessed ASPECTS predicts functional outcomes comparably accurate to automated CT perfusion in the 6-24 h window.

Automated CT perfusion (aCTP) is commonly used to select patients with anterior circulation large vessel occlusion (aLVO) for endovascular treatment (EVT). The equivalence of visually assessed Non-contrast CT Alberta Stroke Program Early CT Scores (ASPECTS) and aCTP based selection in predicting favorable functional outcomes remains uncertain. Retrospective multicenter study of adult aLVO patients from the Swiss Stroke Registry (2014-2021) treated with EVT or best medical treatment 6-24 h after stroke onset. We assessed ASPECTS on non-contrast CT visually and ischemic core volumes on aCTP, defining ASPECTS 0-5 and aCTP CBF < 30% volumes ⩾50 mL as large ischemic cores. We used logistic regression to explore the association between CT modalities and favorable functional outcomes (modified Rankin Scale [mRS] score shift toward lower categories) at 3 months. Receiver operating characteristic (ROC) curve analysis compared the predictive accuracy of visually assessed ASPECTS and aCTP ischemic core for favorable outcomes (mRS 0-2) at 3 months. Of 210 patients, 11.4% had ASPECTS 0-5, and 12.9% aCTP core volumes ⩾50 mL. Within the same model, ASPECTS but not aCTP core volumes were associated with favorable outcomes (ASPECTS: acOR 1.85, 95%CI 1.27-2.70, p = 0.001). The ROC curve analyses showed comparable diagnostic accuracy in predicting favorable functional outcomes (mRS 0-2) at 3 months (ROC areas: ASPECTS 0.80 [95%CI 0.74-0.86] vs aCTP core 0.79 [95%CI 0.72-0.85]). In patients with aLVO, visually assessed ASPECTS showed at least comparable accuracy to automatically generated CTP core volumes in predicting functional outcomes at 3 months.

Acute middle cerebral artery occlusion due to a small internal carotid aneurysm cavity with blood stagnation: illustrative case.

In cerebral large vessel occlusion, even when an aneurysm is close to the target vessel, if the aneurysm is relatively small and angiography shows no thrombus within the aneurysm, it is difficult to identify the aneurysm as the embolic source. A 67-year-old man with a history of two left-sided cerebral infarctions developed a small left-sided cerebral infarction. On hospital day 3, he developed a left M2 occlusion and underwent thrombectomy with retraction of a stent retriever into an aspiration catheter at the proximal end of the thrombus. A red thrombus was retrieved, and M2 recanalization was successfully achieved. Angiography revealed a large partially thrombotic aneurysm with a small cavity with blood stagnation in the left cervical internal carotid artery, which was considered the embolic source. Stent-assisted coil embolization was performed on the aneurysm, and no recurrent cerebral infarction was observed after embolization. In cerebral large vessel occlusion, an aneurysm cavity with blood stagnation may be the embolic source. Using an aspiration catheter alone or retracting a stent retriever into an aspiration catheter could be a useful technique and help to avoid interference between the aneurysm and the stent retriever. https://thejns.org/doi/10.3171/CASE24406.

Large vessel occlusion mediated fluid attenuated inversion recovery signal intensity ratio is associated with stroke within 4.5 h.

The primary objective was to investigate the value of the fluid attenuated inversion recovery (FLAIR) signal intensity ratio (SIR) in identifying stroke within 4.5 h. The secondary objective was to ascertain whether large vessel occlusion (LVO) mediated the relationship between the SIR and stroke within 4.5 h. We analyzed 633 acute stroke patients within 24 h of clear symptom onset. The SIR and DWI-FLAIR mismatch were evaluated. First, we determined whether demographic variables, vascular risk factors and LVO were related to stroke within 4.5 h with multivariate logistic regression analyses and stratified regression analysis. Next, we used mediation analysis to determine whether LVO explained the association between SIR and stroke within 4.5 h. Finally, we used receiver operating characteristic (ROC) analysis to assess the value of SIR, independent variable, and multiparameter models in identifying stroke within 4.5 h and compared with DWI-FLAIR mismatch. Hyperlipemia, LVO and SIR were associated with stroke within 4.5 h. Mediation analysis revealed that LVO partially mediated the relationship between SIR and stroke within 4.5 h (p < 0.001). The multiparameter model (hyperlipemia, LVO and SIR) showed significantly improved performance (AUC 0.869) in identifying stroke within 4.5 h over DWI-FLAIR mismatch (0.684), hyperlipemia (0.632), LVO (0.667) and SIR (0.773) models. SIR is associated with stroke within 4.5 h, and LVO partially mediates this relationship. A multiparameter model combining hyperlipemia, LVO and SIR can more accurately identify stroke within 4.5 h than individual parameter models.

High Hypoperfusion Intensity Ratio Is Independently Associated with Very Poor Outcomes in Large Ischemic Core Stroke.

Recent advances have highlighted the efficacy of endovascular thrombectomy (EVT) in patients with large ischemic core stroke, yet asignificant portion still experience very poor outcomes, defined as a90-day modified Rankin Score (mRS) of 5-6. This study aims to investigate the hypoperfusion intensity ratio (HIR) as aprognostic imaging parameter for these outcomes. In amulticenter retrospective cohort study, data from consecutive patients undergoing EVT for acute ischemic stroke with large vessel occlusion (AIS-LVO) at two comprehensive stroke centers were analyzed. The study included patients with an Alberta Stroke Program Early CT Score (ASPECTS) of5 or less and utilized pretreatment perfusion imaging to calculate HIR. The primary outcome was very poor outcomes (90days mRS 5-6). Among 102 patients included, 59 (57.8%) had very poor outcome (90days mRS 5-6). Multivariable logistic regression analysis adjusting for multiple covariates including admission National Institutes of Health Stroke Scale (NIHSS) and EVT revealed that higher admission NIHSS (adjusted odds ratio [aOR] 1.224, 95% CI 1.089-1.374, p = 0.001) and HIR (aOR per 0.1 incremental change, 1.34, 95% CI 1.02-1.82, P = 0.042) were independently associated with very poor outcomes. This study demonstrates that admission NIHSS and HIR are independently associated with very poor outcome (90days mRS 5-6) in patients with large ischemic core strokes. These findings highlight the importance of collateral status and perfusion imaging in predicting outcomes in this patient population, suggesting apotential role for HIR in the triage and management of large core stroke patients.

7647 Myxedema Coma- A Rare and Fatal Manifestation of Severe Hypothyroidism

Abstract Disclosure: B.K. Ray: None. R. Kaur: None. L. Kaur: None. M. Thakur: None. Introduction: Myxedema coma is a severe and life-threatening form of hypothyroidism. It is a rare occurrence with an incidence of 0.22 per million per year, associated with a high mortality rate ranging from 30 to 60% even with early diagnosis and treatment. This condition arises when the body's response to hypothyroidism is overwhelmed by factors like infection, surgery, and medication noncompliance. The definitive management is with thyroid hormones but supportive measures and identification and treatment of the precipitating factors is also vital. The case discussed concerns an elderly woman with myxedema coma due to noncompliance to Levothyroxine. This case stresses the importance of consistent medical follow-ups. Case Presentation: A 73 year old female presented to the hospital with altered mental status for about 32 hours. Vital signs at presentation showed hypotension (80/50 mmHg), bradycardia (54 beats per minute), tachypnea (32 breaths per minute) and hypothermia (33.2 °C). A computed tomography scan of the brain and Computed tomography angiography of the head/neck showed no stenosis or large vessel occlusion of the vasculature. Initial pertinent laboratory test results revealed a white blood cell count of 6.1 (3.7–11.0×103/uL), hemoglobin level of 14.3 (11.5–16.0 g/dL), sodium level of 131 (136–145 mmol/L), glucose level of 142 (65–125 mg/dL). Troponin, lactate and procalcitonin were normal. She was intubated and transferred to the Intensive care unit. Thyroid function tests revealed a markedly elevated TSH of 37.9 (0.4 to 4.0 mIU/L) and a decreased T4 of 0.3 (0.9-1.7 ng/dL). She was immediately started on hydrocortisone 100 mg Three times daily and initiated on intravenous levothyroxine monotherapy with a loading dose of 200 mcg followed by 100 mcg daily. Her T4 level was trended daily and she demonstrated gradual improvement. She was successfully extubated. On discussion she reported noncompliance with her medications. Hydrocortisone was tapered and she was started on her home dose of oral Levothyroxine (200 mcg) after four days of Intravenous levothyroxine. She was counselled on medication compliance and discharged to home. Conclusion: Myxedema, an extreme form of hypothyroidism, is life-threatening and requires immediate admission to intensive care. Symptoms are usually vague, and require a high degree of suspicion. Treatments include thyroid hormone supplementation, steroid replacement and supportive care. Early detection and quick intervention are crucial for survival. Patient education on medication compliance, regular testing, and reporting new medication to prevent interference with thyroid metabolism is crucial. Presentation: 6/1/2024

8158 Transient Blindness In Metformin-Associated Lactic Acidosis

Abstract Disclosure: Y. Abouelkheer: None. A. Nasir: None. M. Ibrahem: None. Transient Blindness in Metformin-associated Lactic Acidosis Background: Metformin-associated lactic acidosis (MALA) is a rare side effect of metformin use. MALA can result in acute transient blindness in patients with severe metabolic derangements. Clinical Case: A 62-year-old woman presented with severe diarrhea, poor oral intake, malaise, and vomiting on a background of metformin-treated type 2 diabetes mellitus. Laboratory investigations showed bicarbonate &amp;lt;2 mmol/L, anion gap 48 mmol/L, lactic acid 20.5 mmol/L, serum osmolality 352 mOsm/kg, negative urine toxicology screen, and positive SARS-CoV-2. In the emergency department, the patient developed sudden onset bilateral vision loss. The examination was remarkable for complete vision loss bilaterally in all fields, associated with minimally reactive pupils and spontaneous ocular movements with an otherwise unrevealing neurological examination. Computed Tomography (CT) of the brain with stroke protocol showed no evidence of acute intracranial process. CT angiogram of the brain and neck showed patent intracranial and cervical vasculature without high-grade stenosis, large vessel occlusion, or aneurysm. While receiving medical management with intravenous fluid resuscitation and sodium bicarbonate supplementation, the patient had a spontaneous return of vision with no additional neurological complications or deficits. The severe metabolic derangements were associated with distributive shock, requiring admission to the intensive care unit for urgent hemodialysis, pressor support, empiric antibiotics, and stress-dose steroids. Shortly after the patient’s only hemodialysis session, we noted the resolution of her critical metabolic disturbances, renal failure, and shock state. Laboratory investigations post-dialysis showed bicarbonate 12 mmol/L, anion gap 36 mmol/L, and lactic acid 10.5 mmol/L. Follow-up MRI showed chronic lacunar infarct of the left basal ganglia, and she was discharged home six days later. Conclusion: Transient blindness in MALA can mimic acute neurovascular events. Prompt correction of metabolic derangements can aid in reversing systemic symptoms and blindness. Reference: DeFronzo R, Fleming GA, Chen K, Bicsak TA. Metformin-associated lactic acidosis: Current perspectives on causes and risk. Metabolism. 2016;65(2):20-29. doi:10.1016/j.metabol.2015.10.014 Presentation: 6/2/2024

Catheter-related internal jugular vein thrombosis in neonates and long-term consequences: a prospective cohort study.

The incidence of central venous catheter-related thrombosis and the long-term effects of thrombosis on catheterized veins in neonates is unknown. We therefore determined the incidence of central venous thrombosis, identified associated risk factors, and evaluated outcomes at 6 months. We enrolled neonates aged less than 28 days scheduled for major intestinal or cardiac surgery whom we expected to require central venous catheters for at least 48 hours. Catheter size, insertion method, and puncture site were determined by the attending anesthesiologist. The duration of catheterization was also determined by clinical need. Central venous thrombi were diagnosed by color Doppler ultrasound imaging within 48 hours after catheter removal; results were not shared with clinicians. Ultrasound examinations were repeated 1, 3, and 6 months after discharge. We enrolled 188 neonates over 2 years. The median duration of catheter insertion was 12 days. 128 (68%) of the neonates had central venous thrombi at the catheter site, all of which were asymptomatic. Among patients with thrombi, 29 (23%) had complete vessel occlusion and 5 (4%) had venous stenosis at 6 months after discharge. Thrombi therefore spontaneously resolved by 6 months in 73% of the neonates. CVC/vein diameter ratio, duration of catheterization, and catheter dysfunction were independent risk factors for vessel thrombus. Complete vessel occlusion was most common in patients whose thrombus occupied more than 58% of the vessel at the initial assessment. Covert central venous thrombosis is frequent in neonates who have central venous catheters, and complications are most common in patients who have large intravascular thrombi. Neonates with large intravascular thrombi should be followed, and considered for anticoagulation.

Emergent endovascular treatment versus medical treatment for acute large vessel occlusions with nondisabling symptoms.

The aim of this study is to analyze the effectiveness and safety of medical treatment (MT) versus endovascular treatment (EVT) in acute large vessel occlusion patients with mild nondisabling stroke symptoms. This study is a multicenter observational study in which data from patients at three stroke centers were prospectively obtained and retrospectively analyzed. Patients were included if they arrived for treatment within 6 h of stroke onset or last known well time and had a baseline National Institutes of Health Stroke Scale (NIHSS) score of ≤5. Primary outcome was modified Rankin Scale (mRS) score 0-2 at 90 days. Secondary outcomes included symptomatic intracranial hemorrhage (sICH), discharge NIHSS score, 90-day all-cause mortality and length of stay. Clinical outcomes were compared through a multivariable logistic regression after adjusting for age, treatment type admission and discharge NIHSS score, admission Alberta Stroke Program Early CT (ASPECT) score and length of stay. Of the 82 patients included in the study, 42 were in the EVT group and 40 were in the MT group. The groups were similar in age (MT:66, EVT:64 age; p = .62), gender (MT:55%, EVT:54.8%; male) admission NIHSS score (MT:2, EVT:3 points; p = .26), ASPECT score (MT:10, EVT:9; p = .15). While discharge NIHSS score was found to be statistically significant between the groups (MT:1, EVT:2; p = .04). There was no difference between the two groups in terms of 90-day mRS scores (MT:1, EVT:1, p = .86) and mortality rates (MT:4, EVT:4; p = .94). In unadjusted analysis, sICH rates were similar between the MT and EVT groups (MT 5%, EVT 7.1%, p = .52). Neurological intensive care unit length of stay (MT:5 days, EVT:2 days p < .001), inpatient clinic length of stay (MT:3, EVT:2 days p = .041), and total length of stay (MT:9 days, EVT:4 days p < .001) were significantly longer in the MT group. Our multicenter study demonstrated that MT with blood pressure augmentation and anticoagulation at hyperacute stage is an alternative option for emergency large vessel occlusion patients with nondisabling mild stroke symptoms.

Emerging Thrombotic Disorders Associated with Virus-Based Innovative Therapies: From VITT to AAV Gene Therapy-Related Thrombotic Microangiopathy.

Gene therapy is a promising therapeutic approach for treating life-threatening disorders. Despite the clinical improvements observed with gene therapy, immune responses either innate or adaptive against the vector used for gene delivery, can affect treatment efficacy and lead to adverse reactions. Thrombotic microangiopathy (TMA) is a thrombosis with thrombocytopenia syndrome (TTS) characterized by microangiopathic hemolytic anemia, thrombocytopenia, and small vessel occlusion known to be elicited by several drugs, that has been recently reported as an adverse event of adeno-associated virus (AAV)-based gene therapy. TMA encompasses a heterogenous group of disorders, its classification and underlining mechanisms are still uncertain, and still lacks validated biomarkers. The identification of predictors of TMA, such as vector dose and patient characteristics, is a pressing need to recognize patients at risk before and after AAV-based gene therapy administration. This review aims to explore the literature on TMA associated with AAV-based gene therapy in the larger context of TMA (i.e., hemolytic-uremic syndrome, thrombotic thrombocytopenic purpura, and other drug-related TMAs). Considering the wide attention recently gained by another TTS associated with a non-gene therapy viral platform (adenovirus, AV COVID-19 vaccine), namely vaccine-induced immune thrombocytopenia and thrombosis (VITT), AAV gene therapy-related TMA mechanisms will be discussed and differentiated from those of VITT to avoid recency bias and favor a correct positioning of these two recently emerged syndromes within the heterogenous group of drug-related TTS. Finally, the review will discuss strategies for enhancing the safety and optimize the management of AAV-based gene therapy that is emerging as an efficacious therapeutic option for disparate, severe, and often orphan conditions.

Improving Stroke Outcome Prediction Using Molecular and Machine Learning Approaches in Large Vessel Occlusion.

Introduction: Predicting stroke outcomes in acute ischemic stroke (AIS) can be challenging, especially for patients with large vessel occlusion (LVO). Available tools such as infarct volume and the National Institute of Health Stroke Scale (NIHSS) have shown limited accuracy in predicting outcomes for this specific patient population. The present study aimed to confirm whether sudden metabolic changes due to blood-brain barrier (BBB) disruption during LVO reflect differences in circulating metabolites and RNA between small and large core strokes. The second objective was to evaluate whether integrating molecular markers with existing neurological and imaging tools can enhance outcome predictions in LVO strokes. Methods: The infarction volume in patients was measured using magnetic resonance diffusion-weighted images, and the 90-day stroke outcome was defined by a modified Rankin Scale (mRS). Differential expression patterns of miRNAs were identified by RNA sequencing of serum-driven exosomes. Nuclear magnetic resonance (NMR) spectroscopy was used to identify metabolites associated with AIS with small and large infarctions. Results: We identified 41 miRNAs and 11 metabolites to be significantly associated with infarct volume in a multivariate regression analysis after adjusting for the confounders. Eight miRNAs and ketone bodies correlated significantly with infarct volume, NIHSS (severity), and mRS (outcome). Through integrative analysis of clinical, radiological, and omics data using machine learning, our study identified 11 top features for predicting stroke outcomes with an accuracy of 0.81 and AUC of 0.91. Conclusions: Our study provides a future framework for advancing stroke therapeutics by incorporating molecular markers into the existing neurological and imaging tools to improve predictive efficacy and enhance patient outcomes.

Effect of occlusion site on the effectiveness and safety of endovascular thrombectomy for large ischemic cores: A cohort study.

Recent clinical trials have shown that patients with large ischemic cores have better outcomes with endovascular thrombectomy (EVT) compared with standard medical treatment (SMT) alone.We aim to assess whether the relationship between EVT and improvements in clinical outcomes varies depending on the location of the occlusive sites. This study is a subgroup analysis conducted within a prospective, nationwide, multi-center registry. The cohort included patients with acute large vessel occlusion in the anterior circulation and an Alberta Stroke Program Early Computed Tomography Score of 0 to 5 within 24 hours from last known well. We utilized the adjusted common odds ratio for a shift toward better outcome on the modified Rankin Scale after EVT compared with SMT alone as the primary outcome. Safety outcomes included symptomatic intracranial hemorrhage (sICH). A total of 745 patients with large ischemic cores were included: 272(36.5%) with internal carotid artery occlusion, 392(52.6%) with M1 segment of the middle cerebral artery occlusion, and 81(11.0%) with M2 segment of the middle cerebral artery occlusion. The adjusted common odds ratios were as follows: 1.98 (95% CI, 1.01-3.89) for ICA occlusions, 2.09 (95% CI, 1.35-3.23) for M1 occlusions, and 1.13 (95% CI, 0.43-2.94) for M2 occlusions. There was no significant treatment-by-occlusion site interaction observed (P=0.69). However, the incidence of sICH was significantly greater in all groups receiving EVT than in those receiving SMT alone. Additionally, we observed that the secondary outcomes and subgroup analyses were generally consistent with the main outcomes. In this study, we found that patients with internal carotid artery and M1 occlusion demonstrated a better outcome with EVT, while the benefit for patients with M2 occlusion remains uncertain.

Evaluation of a low-cost portable NIRS device for monitoring muscle ischemia.

The main objective of this study is to evaluate the low-cost, open-source HEGduino device as a tissue oximetry monitor to advance the research of somatic NIRS monitoring. Specifically, this study analyzes the use of this portable functional NIRS system for detecting the cessation of blood flow due to vascular occlusion in an upper limb.19 healthy patients aged between 25 and 50 were recruited and monitored using HEGduino device. Participants underwent a vascular occlusion test on one forearm. Raw values collected by HEGduino as well as the processed variables derived from the measurements were registered. Additional variables to characterize the signal noise during the tests were also recorded.The results of the data distribution curves for all the subjects in the study accurately detected the physiological events associated with transient tissue ischemia. The statistical analysis of the recorded data showed that the difference between the baseline values recorded by the red led (RED) and its normalized minimum variable was always different from zero (p < 0.014). Furthermore, the difference between the normalized baseline values recorded by the infrared led (IR) and the corresponding normalized minimum value was also different from zero (p < 0.001). The R-squared coefficient of determination for the noise variables considered in this study on the normalized RED and IR values was 0.08 and 0.105, respectively.The study confirms the potential of HEGduino system to detect an interruption of the blood flow by means of variations in regional tissue oxygen saturation. This study demonstrates the potential of the HEGduino device as a monitoring alternative to advance the study of the applicability of NIRS in muscle tissue oximetry.

Intra-arterial tenecteplase after successful endovascular therapy (ANGEL-TNK): protocol of a multicentre, open-label, blinded end-point, prospective, randomised trial

BackgroundDespite successful reperfusion after thrombectomy for large vessel occlusion (LVO) stroke, up to half of patients are dependent or dead at 3-month follow-up.The aim of the current study is to...

Incidence of intraocular inflammation and its risk factors in patients treated with brolucizumab: a nationwide cohort study

This study aimed to evaluate the incidence of clinically significant intraocular inflammation (csIOI) after treatment with intravitreal injection (IVI) of brolucizumab and identify csIOI risk factors. We categorized 60,966 South Korean patients from a nationwide population-based cohort into 4 groups: groups 1 (Ranibizumab), 2 (Aflibercept), 3 (Brolucizumab), and 4 (switched to brolucizumab). We used the Kaplan–Meier method to estimate the cumulative incidence of csIOI in each group and calculated the hazard ratios (HRs) and 95% confidence intervals (CIs). We constructed a multivariate model using forward selection methods to identify risk factors for csIOI. The cumulative incidence of csIOI within 180 days of the index date in groups 1, 2, 3, and 4 was 0.36% (67/18,537), 0.49% (186/37,951), 3.47% (38/1,095), and 3.69% (125/3,383), respectively. Multivariate analysis revealed a significant increase in csIOI risk in groups 3 (HR 11.08, 95% CI 7.42–16.53, P < 0.001) and 4 (HR 10.40, 95% CI 7.67–14.09, P < 0.001). History of retinal vascular occlusion (HR 1.56, 95% CI 1.01–2.40, P = 0.043) significantly increased csIOI risk after brolucizumab IVI treatment; female sex (HR 0.78, 95% CI 0.64–0.96, p = 0.020) and diabetes (HR 0.72, 95% CI 0.58–0.90, p = 0.004) decreased the risk. csIOI incidence was higher after brolucizumab IVI treatment than after ranibizumab and aflibercept IVI treatment. Retinal vein occlusion history, female sex, and diabetes are associated with csIOI after brolucizumab IVI treatment.

Decreased Quantitative Cerebral Blood Volume Is Associated With Poor Outcomes in Large Core Patients.

Recent large core trials have highlighted the effectiveness of mechanical thrombectomy (MT) in acute ischemic stroke with large vessel occlusion. Variable perfusion-imaging thresholds and poor Alberta Stroke Program Early Computed Tomography Score reliability underline the need for more standardized, quantitative ischemia measures for MT patient selection. We aimed to identify the computed tomography perfusion parameter most strongly associated with poor outcomes in patients with acute ischemic stroke-large vessel occlusion with significant ischemic cores. In this study from 2 comprehensive stroke centers from 2 comprehensive stroke centers within the Johns Hopkins Medical Enterprise (Johns Hopkins Hospita-East Baltimore and Bayview Medical Campus) from July 29, 2019 to January 29, 2023 in a continuously maintained database, we included patients with acute ischemic stroke-large vessel occlusion with ischemic core volumes defined as relative cerebral blood flow <30% and ≥50 mL on computed tomography perfusion or Alberta Stroke Program Early Computed Tomography Score <6. We used receiver operating characteristics to find the optimal cutoff for parameters like cerebral blood volume (CBV) <34%, 38%, 42%, and relative cerebral blood flow >20%, 30%, 34%, 38%, and time-to-maximum >4, 6, 8, and 10 seconds. The primary outcome was unfavorable outcomes (90-day modified Rankin Scale score 4-6). Multivariable models were adjusted for age, sex, diabetes, baseline National Institutes of Health Stroke Scale, intravenous thrombolysis, and MT. We identified 59 patients with large ischemic cores. A receiver operating characteristic curve analysis showed that CBV<42% ≥68 mL is associated with unfavorable outcomes (90-day modified Rankin Scale score 4-6) with an area under the curve of 0.90 (95% CI, 0.82-0.99) in the total and MT-only cohorts. Dichotomizing at this CBV threshold, patients in the ≥68 mL group exhibited significantly higher relative cerebral blood flow, time-to-maximum >8 and 10 seconds volumes, higher CBV volumes, higher HIR, and lower CBV index. The multivariable model incorporating CBV<42% ≥68 mL predicted poor outcomes robustly in both cohorts (area under the curve for MT-only subgroup was 0.87 [95% CI, 0.75-1.00]). CBV<42% ≥68 mL most effectively forecasts poor outcomes in patients with large-core stroke, confirming its value alongside other parameters like time-to-maximum in managing acute ischemic stroke-large vessel occlusion.

Microsurgical Anatomy of the Lateral Posterior Choroidal Artery and Its Thalamic Branches

Only a few articles have been published about the lateral posterior choroidal artery (LPChA), and yet none of them contains data regarding the thalamic branches. The LPChA and its twigs of the 26 cerebral hemispheres were injected with a mixture of a 10% Indian ink and gelatin. Following fixation in a 10% formaldehyde solution, the vessels were micro dissected under the stereoscopic microscope. In addition, serial cerebral angiograms of the 168 patients were examined. The LPChA, which was commonly singular or double and averaged 0.68 mm in diameter, most often originated from the P2 and P3 segments (76%) of the posterior cerebral artery (PCA). It always gave off the choroidal, pulvinar and typical thalamic branches, occasionally the parahippocampal (4%), hippocampal (8%), peduncular (8%), tegmental (12%), pretectal (4%), lateral geniculate (40%) and medial geniculate twigs (16%), and the forniceal, subependymal (100%), stria terminalis (32%), and caudate twigs (28%). The pulvinar and thalamic branches averaged almost 4 in number and 0.27 mm in diameter. They most often supplied the pulvinar nuclei, and occasionally portions of the mediodorsal, lateral dorsal, lateral posterior, ventral lateral, and the ventral posterior thalamic nuclei. Among the 168 serial cerebral angiograms, one presented the arteriovenous malformation of the LPChA, but no one showed an aneurysm. This is the first description of the LPChA thalamic branches to date. Their microanatomic features are important for understanding the neurologic symptoms following vessels occlusion, for precise radiologic diagnoses, and for safe neurosurgical and endovascular interventions.

Safe Endovascular Recanalization of Internal Carotid Artery Occlusion Using Retrograde Aspiration Angiography

ObjectsCerebral infarction, resulting from acute internal carotid artery (ICA) occlusion, typically manifests with a wide ischemic area and severe symptoms. Mechanical thrombectomy proves effective within 24 hours of disease onset and in less ischemic infarction core. However, in cases with well-developed collateral flow and mild symptoms, conservative treatment is initially selected. If symptoms worsen or ipsilateral hemisphere perfusion decreases, superficial temporal artery (STA) – middle cerebral artery (MCA) anastomosis is considered. Revascularization therapy may also be effective. Contralateral angiography allows for ipsilateral blood flow verification once complete revascularization is achieved, albeit with potential treatment-related complications. Here, we describe retrograde angiography using an intermediate catheter (IMC) and contralateral contrast injection to achieve safer revascularization. MethodsWe present ten acute ICA occlusion cases caused by thromboembolism, arteriosclerosis, carotid artery stent occlusion, or embolic stroke of undetermined source. Employing bilateral femoral artery puncture, one catheter was guided to the occluded ICA, while another was positioned for diagnostic purposes in the contralateral ICA or vertebral artery. The IMC was navigated through the occluded vessel, with contralateral imaging performed during aspiration. The catheter was gradually retracted to confirm the extent of occlusion and recognize recanalization. ResultsRecanalization was successfully achieved in all cases. Symptomatic ischemic complication and hyperperfuison was not seen in all cases. No cases were decreased modified Rankin scale after treatment. ConclusionAdvancements in IMC technology facilitate distal catheter guidance to the ICA, even in proximal occlusion. Combining this technique with contralateral imaging allows us to confirm the extent of occlusion and recanalization status without antegrade imaging, making recanalization therapy safer.

Nanoparticle delivery of VEGF and SDF-1α as an approach for treatment of pulmonary arterial hypertension.

Endothelial dysfunction is an underlying mechanism for the development of pulmonary arterial hypertension (PAH). Vascular endothelial growth factor (VEGF) and stromal cell-derived factor-1α (SDF) may help repair the dysfunctional endothelium and provide treatment for PAH. To examine this possibility, nanoparticles carrying human recombinant VEGF and SDF (VEGFNP and SDFNP) were aerosolized into the lungs of nude rats at Day 14 after monocrotaline (MCT) injection and analyses were performed at Day 28. The data show that the VEGFNP/SDFNP delivery led to a lower pulmonary arterial pressure and prevented right ventricular hypertrophy in the MCT rats: the right ventricular systolic pressure of the control, MCT, and MCT + VEGFNP/SDFNP treatment groups were 29±2, 70±9, and 44±5 (mean±SD) mmHg, respectively; the pulmonary vascular resistance indices of the groups were 0.6±0.3, 3.2±0.7, and 1.7±0.5, respectively; and the Fulton indices [-RV/(LV + Septum)] were 0.22±0.01, 0.44±0.07, and 0.23±0.02, respectively. The VEGFNP/SDFNP delivery delayed the thickening of distal pulmonary vessels: the number of nearly occluded vessels in a whole lung section from the MCT and MCT + VEGFNP/SDFNP groups were 46±12 and 2±3, respectively. Gene expression analysis of the endothelial cell markers, VE-cadherin, KDR, BMPR2, and eNOS, and smooth cell markers, SM-MHC and α-SMA, indicated significant loss of distal pulmonary vessels in the MCT- treated rats. VEGFNP/SDFNP delivery did not recover the loss, but significantly increased eNOS and decreased α-SMA expression in the MCT-treated lungs. Thus, the therapeutic effect of VEGFNP/SDFNP may be mediated by improving/repairing endothelial function in the PAH lungs.

Angiographic and Histopathological Characteristics of a Novel Polyacrylate Liquid Embolic Agent Compared with Ethylene Vinyl Alcohol Copolymer in a Large Animal Model

PurposeTo study the in vivo safety and effectiveness of a novel radiopaque nonadhesive polyacrylate (PA) peripheral liquid embolic system (AMBER SEL-P) relative to ethylene vinyl alcohol copolymer (EVOH, Onyx) in a healthy swine endovascular model. Materials and MethodsTwenty-five swine underwent rete mirabile and bilateral kidney embolization with PA or EVOH and were followed up for 24 hours (n = 5) and 30 days (n = 10), and 3 (n = 10) months. Angiographic features (penetrability, radiopacity, catheter entrapment, fragmentation, occlusion, and vasospasm) were evaluated. Necropsy and histology were used to evaluate the nontarget embolization, safety, and target embolization effectiveness by recanalization and analyze the vascular response. ResultsNo adverse events occurred during the embolization process or study period. The angiographic performance confirmed a significant positive effect of PA compared with that of EVOH in terms of penetrability (P = .007), catheter entrapment (P = .007), fragmentation (P = .007), vascular occlusion (P = .038), vasospasm (P = .038), and follow-up vascular occlusion (P = .038). Prenecropsy angiography found no vascular recanalization in the organs treated with PA, whereas it was detected at 3 months in 2 samples treated with EVOH. Histologically, PA was classified as nonirritant compared with EVOH under the study conditions according to ISO 10993-6:2016 as modified. No systemic effects during necropsy were detected in the animals treated with these agents. ConclusionsThis in vivo study concludes that the angiographic behavior of PA has advantages compared with EVOH. The embolization and biocompatibility of PA are similar to those of EVOH. PA is safe and effective for transarterial embolization in an acute, subacute, and chronic endovascular embolization models.