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2.
Ultrasound Med Biol ; 2024 May 23.
Article in English | MEDLINE | ID: mdl-38789304

ABSTRACT

OBJECTIVE: The goal of the work described here was to develop the first neuronavigation-guided transcranial histotripsy (NaviTH) system and associated workflow for transcranial ablation. METHODS: The NaviTH system consists of a 360-element, 700 kHz transmitter-receiver-capable transcranial histotripsy array, a clinical neuronavigation system and associated equipment for patient-to-array co-registration and therapy planning and targeting software systems. A workflow for NaviTH treatments, including pre-treatment aberration correction, was developed. Targeting errors stemming from target registration errors (TREs) during the patient-to-array co-registration process, as well as focal shifts caused by skull-induced aberrations, were investigated and characterized. The NaviTH system was used in treatments of two <96 h post-mortem human cadavers and in experiments in two excised human skullcaps. RESULTS: The NaviTH was successfully used to create ablations in the cadaver brains as confirmed in post-treatment magnetic resonance imaging A total of three ablations were created in the cadaver brains, and targeting errors of 9, 3.4 and 4.4 mm were observed in corpus callosum, septum and thalamus targets, respectively. Errors were found to be caused primarily by TREs resulting from transducer tracking instrument design flaws and imperfections in the treatment workflow. Transducer tracking instrument design and workflow improvements reduced TREs to <2 mm, and skull-induced focal shifts, following pre-treatment aberration correction, were 0.3 mm. Total targeting errors of the NaviTH system following the noted improvements were 2.5 mm. CONCLUSIONS: The feasibility of using the first NaviTH system in a human cadaver model has been determined. Although accuracy still needs to be improved, the proposed system has the potential to allow for transcranial histotripsy therapies without requiring active magnetic resonance treatment guidance.

3.
Gels ; 10(4)2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38667661

ABSTRACT

The problem that this study addresses is to understand how microwave radiation is able to degrade genomic DNA of E. coli. In addition, a comparative study was made to evaluate the suitability of a high-throughput automated electrophoresis platform for quantifying the DNA degradation under microwave radiation. Overall, this study investigated the genomic DNA degradation of E. coli under microwave radiation using automated gel electrophoresis. To examine the viable organisms and degradation of genomic DNA under microwave exposure, we used three methods: (1) post-microwave exposure, where E. coli was enumerated using modified mTEC agar method using membrane filtration technique; (2) extracted genomic DNA of microwaved sample was quantified using the Qubit method; and (3) automated gel electrophoresis, the TapeStation 4200, was used to examine the bands of extracted DNA of microwaved samples. In addition, to examine the impacts of microwaves, E. coli colonies were isolated from a fecal sample (dairy cow manure), these colonies were grown overnight to prepare fresh E. coli culture, and this culture was exposed to microwave radiation for three durations: (1) 2 min; (2) 5 min; and (3) 8 min. In general, Qubit values (ng/µL) were proportional to the results of automated gel electrophoresis, TapeStation 4200, DNA integrity numbers (DINs). Samples from exposure studies (2 min, 5 min, and 8 min) showed no viable E. coli. Initial E. coli levels (at 0 min microwave exposure) were 5 × 108 CFU/mL, and the E. coli level was reduced to a non-detectable level within 2 min of microwave exposure. The relationships between Qubit and TapeStation measurements was linear, except for when the DNA level was lower than 2 ng/µL. In 8 min of microwave exposure, E. coli DNA integrity was reduced by 61.7%, and DNA concentration was reduced by 81.6%. The overall conclusion of this study is that microwave radiation had a significant impact on the genomic DNA of E. coli, and prolonged exposure of E. coli to microwaves can thus lead to a loss of genomic DNA integrity and DNA concentrations.

4.
Neuroimaging Clin N Am ; 34(2): 215-224, 2024 May.
Article in English | MEDLINE | ID: mdl-38604706

ABSTRACT

This review article discusses the role of MR imaging-based biomarkers in understanding and managing hemorrhagic strokes, focusing on intracerebral hemorrhage (ICH) and aneurysmal subarachnoid hemorrhage. ICH is a severe type of stroke with high mortality and morbidity rates, primarily caused by the rupture of small blood vessels in the brain, resulting in hematoma formation. MR imaging-based biomarkers, including brain iron quantification, ultra-early erythrolysis detection, and diffusion tensor imaging, offer valuable insights for hemorrhagic stroke management. These biomarkers could improve early diagnosis, risk stratification, treatment monitoring, and patient outcomes in the future, revolutionizing our approach to hemorrhagic strokes.


Subject(s)
Hemorrhagic Stroke , Stroke , Humans , Diffusion Tensor Imaging , Iron , Brain/diagnostic imaging , Cerebral Hemorrhage/complications , Cerebral Hemorrhage/diagnostic imaging , Stroke/diagnostic imaging , Biomarkers , Magnetic Resonance Imaging
5.
Indian J Anaesth ; 68(4): 348-353, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38586272

ABSTRACT

Background and Aims: There is limited data on the effects of norepinephrine on neonatal outcomes and maternal complications relative to other vasopressors. The study aimed to compare neonatal outcomes and maternal complications after bolus intravenous doses of phenylephrine and norepinephrine for post-spinal hypotension in elective caesarean section women. Methods: This randomised study was done on 100 elective caesarean section women under spinal anaesthesia. Block randomisation divided women into two groups to receive intravenous phenylephrine 50 µg bolus (Group A) or norepinephrine 5 µg bolus (Group B) following post-spinal hypotension. Groups were evaluated and compared for umbilical arterial blood gas analysis, birth weight, APGAR (appearance, pulse, grimace, activity, and respiration) score, maternal haemodynamics, and complications. Kolmogorov-Smirnov and Shapiro-Wilk tests were used to verify data normality. Independent samples t-test or Mann-Whitney U test was employed to compare continuous variables based on data normality, and the Chi-square test was used to determine categorical variable associations. Results: Demographic characteristics of women were found to be comparable between groups. Umbilical arterial potential of hydrogen, partial pressure of oxygen, partial pressure of carbon dioxide, base excess, bicarbonate, birth weight, and APGAR scores were comparable across groups, showing no significant differences (P > 0.05). Groups had similar maternal haemodynamic characteristics and episodes of nausea, vomiting, and chest pain across groups without statistical significance (P > 0.05). Conclusion: No notable distinction was found between neonatal outcomes and maternal complications between phenylephrine and norepinephrine bolus regimens. Norepinephrine can be used as an alternative to phenylephrine post-spinal hypotension in women undergoing elective caesarean section.

6.
Stroke ; 55(3): e91-e106, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38299330

ABSTRACT

Cervical artery dissection is an important cause of stroke, particularly in young adults. Data conflict on the diagnostic evaluation and treatment of patients with suspected cervical artery dissection, leading to variability in practice. We aim to provide an overview of cervical artery dissection in the setting of minor or no reported mechanical trigger with a focus on summarizing the available evidence and providing suggestions on the diagnostic evaluation, treatment approaches, and outcomes. Writing group members drafted their sections using a literature search focused on publications between January 1, 1990, and December 31, 2022, and included randomized controlled trials, prospective and retrospective observational studies, meta-analyses, opinion papers, case series, and case reports. The writing group chair and vice chair compiled the manuscript and obtained writing group members' approval. Cervical artery dissection occurs as a result of the interplay among risk factors, minor trauma, anatomic and congenital abnormalities, and genetic predisposition. The diagnosis can be challenging both clinically and radiologically. In patients with acute ischemic stroke attributable to cervical artery dissection, acute treatment strategies such as thrombolysis and mechanical thrombectomy are reasonable in otherwise eligible patients. We suggest that the antithrombotic therapy choice be individualized and continued for at least 3 to 6 months. The risk of recurrent dissection is low, and preventive measures may be considered early after the diagnosis and continued in high-risk patients. Ongoing longitudinal and population-based observational studies are needed to close the present gaps on preferred antithrombotic regimens considering clinical and radiographic prognosticators of cervical artery dissection.


Subject(s)
Carotid Artery, Internal, Dissection , Ischemic Stroke , Stroke , Vertebral Artery Dissection , Humans , Young Adult , American Heart Association , Arteries , Carotid Artery, Internal, Dissection/diagnosis , Carotid Artery, Internal, Dissection/diagnostic imaging , Ischemic Stroke/complications , Prospective Studies , Retrospective Studies , Stroke/diagnostic imaging , Stroke/etiology , Treatment Outcome , Vertebral Artery Dissection/diagnosis , Vertebral Artery Dissection/diagnostic imaging , Adult
7.
Eur Stroke J ; : 23969873241234713, 2024 Feb 25.
Article in English | MEDLINE | ID: mdl-38403924

ABSTRACT

INTRODUCTION: Recent randomized controlled trials demonstrated superiority of mechanical thrombectomy compared to medical therapy in acute basilar artery occlusions, however, little data is available to guide clinicians in functional prognosis and risk stratification. PATIENTS AND METHODS: Data from the retrospectively established PC-SEARCH Thrombectomy registry, which included patients with basilar artery occlusion from eight sites from January 2015 to December 2021, was interrogated. Outcomes were dichotomized into 90-day favorable (mRS ⩽ 3) and unfavorable (mRS > 3). Multivariate logistic regression analysis was performed with respect to the outcome groups and were adjusted for potential confounding baseline characteristics. RESULTS: Four-hundred-forty-four patients were included in this analysis. Mean age was 66 [SD 15], with 56% male, and comprised of 76% Caucasian. Patients presented with an initial median NIHSS of 18 and 199 patients (44.8%) achieved favorable 90-day functional outcomes. Independent predictors of favorable outcomes included younger age, pc-ASPECTS > 8 (OR 2.30 p < 0.001), and TICI ⩾ 2b (OR 7.56 p < 0.001). Unfavorable outcomes were associated with increasing number of passes (OR 1.29 p = 0.004) and sICH (OR 4.19 p = 0.015). IA-tPA was an independent risk factor for sICH (OR 7.15 p = 0.002) without improving favorable functional outcomes. CONCLUSION AND DISCUSSION: PC-ASPECTS > 8, successful recanalization (TICI ⩾ 2b), first-pass recanalization, and younger age are independent predictors of favorable 90-day functional outcome in thrombectomy treated patients with acute basilar artery occlusion. Conversely, sICH were independent predictors of unfavorable outcomes. IA-tPA and unsuccessful recanalization are independently associated with sICH.

8.
Ultrasound Med Biol ; 50(5): 639-646, 2024 05.
Article in English | MEDLINE | ID: mdl-38302370

ABSTRACT

OBJECTIVE: Transcranial histotripsy has shown promise as a non-invasive neurosurgical tool, as it has the ability to treat a wide range of locations in the brain without overheating the skull. One important effect of histotripsy in the brain is the blood-brain barrier (BBB) opening (BBBO) at the ablation site, but there is a knowledge gap concerning the extent of histotripsy-induced BBBO. Here we describe induction of BBBO by transcranial histotripsy and use of magnetic resonance imaging (MRI) and histology to quantify changes in BBBO at the periphery of the histotripsy ablation zone over time in the healthy mouse brain. METHODS: An eight-element, 1 MHz histotripsy transducer with a focal distance of 32.5 mm was used to treat the brains of 23 healthy female BL6 mice. T1-gadolinium (T1-Gd) MR images were acquired immediately following histotripsy treatment and during each of the subsequent 4 wk to quantify the size and intensity of BBB leakage. RESULTS: The T1-Gd MRI results revealed that the hyperintense BBBO volume increased over the first week and subsided gradually over the following 3 wk. Histology revealed complete loss of tight junction proteins and blood vessels in the center of the ablation region immediately after histotripsy, partial recovery in the periphery of the ablation zone 1 wk following histotripsy and near-complete recovery of tight junction complex after 4 wk. CONCLUSION: These results provide the first evidence of transcranial histotripsy-induced BBBO and repair at the periphery of the ablation zone.


Subject(s)
Blood-Brain Barrier , High-Intensity Focused Ultrasound Ablation , Mice , Female , Animals , Blood-Brain Barrier/diagnostic imaging , Blood-Brain Barrier/metabolism , Brain/diagnostic imaging , Liver/surgery , High-Intensity Focused Ultrasound Ablation/methods , Skull
9.
Front Neurol ; 15: 1352310, 2024.
Article in English | MEDLINE | ID: mdl-38343711

ABSTRACT

Importance: Stroke-to-recanalization time is a strong predictor of outcomes in anterior circulation large-vessel occlusion (LVO). The authors aimed to evaluate functional outcomes in early (<6 h) vs. late (6-24 h) time windows for thrombectomy-treated basilar artery occlusions. Methods: Patients were derived from the Posterior Circulation Ischemic Stroke Evaluation: Analyzing Radiographic and Intra-procedural Predictors of Mechanical Thrombectomy (PC-SEARCH) Registry and retrospectively analyzed early and late basilar artery thrombectomy time windows cohorts. Patients were dichotomized based on the last known well and correlated to 90-day functional outcomes (mRS 0-3). A multiple logistic regression analysis was performed. Results: A total of 405 patients were included in this study: 216 and 189 patients in the early and late time windows, respectively. Baseline demographic, stroke, radiographic, and intraprocedural characteristics were similar between the groups. A total of 99 (46%) and 79 (42%) patients in the early and late time windows, respectively, achieved favorable functional outcomes at 90 days (p = 0.41), and multiple logistic regression analysis did not reveal differences between cohorts (OR: 0.74; 95% CI: 0.46-1.19; p = 0.22). Symptomatic hemorrhage (7% vs. 5%; p = 0.69) and neurological complications (8% vs. 9%; p = 0.83) were similar between the groups; however, hospital complications were more common in the early time window cohort (22% vs. 13%; p = 0.01). Conclusion: The early and late thrombectomy time windows can achieve similar rates of 90-day favorable functional outcomes. However, timely thrombectomy influences the likelihood of achieving excellent functional outcomes (mRS ≤ 2) within the early time window.

11.
Comput Biol Med ; 167: 107648, 2023 12.
Article in English | MEDLINE | ID: mdl-37931523

ABSTRACT

Developing fully automatic and highly accurate medical image segmentation methods is critically important for vascular disease diagnosis and treatment planning. Although advances in convolutional neural networks (CNNs) have spawned an array of automatic segmentation models converging to saturated high performance, none have explored whether CNNs can achieve (spatially) tunable segmentation. As a result, we propose multiple attention modules from a frequency-domain perspective to construct a unified CNN architecture for segmenting vasculature with desired (spatial) scales. The proposed CNN architecture is named frequency-domain attention-guided cascaded U-Net (FACU-Net). Specifically, FACU-Net contains two innovative components: (1) a frequency-domain-based channel attention module that adaptively tunes channel-wise feature responses and (2) a frequency-domain-based spatial attention module that enables the deep network to concentrate on foreground regions of interest (ROIs) effectively. Furthermore, we devised a novel frequency-domain-based content attention module to enhance or weaken the high (spatial) frequency information, allowing us to strengthen or eliminate vessels of interest. Extensive experiments using clinical data from patients with intracranial aneurysms (IA) and abdominal aortic aneurysms (AAA) demonstrated that the proposed FACU-Net met its design goal. In addition, we further investigated the association between varying (spatial) frequency components and the desirable vessel size/scale attributes. In summary, our preliminary findings are encouraging, and further developments may lead to deployable image segmentation models that are spatially tunable for clinical applications.


Subject(s)
Aortic Aneurysm, Abdominal , Intracranial Aneurysm , Humans , Neural Networks, Computer , Image Processing, Computer-Assisted
13.
Stroke ; 54(10): 2512-2521, 2023 10.
Article in English | MEDLINE | ID: mdl-37747965

ABSTRACT

BACKGROUND: Aspiration catheters (ASPs) and stentriever thrombectomy devices have comparable safety and efficacy in anterior circulation ischemic strokes. However, there is lack of high-quality comparative data in acute basilar artery occlusions. Our objective is to compare the outcomes and safety of ASPs and stentriever devices in acute basilar artery occlusions. METHODS: This is an analysis of the retrospectively established PC-SEARCH Thrombectomy (Posterior-Circulation Ischemic Stroke Evaluation: Analyzing Radiographic and Intraprocedural Predictors for Mechanical Thrombectomy) registry. Patients were dichotomized based on their first-line thrombectomy device (ASP and stentriever) and associated with their 90-day functional outcomes, intraprocedural metrics, and safety measures. Propensity analysis based on unequal baseline characteristics was performed. Consecutive patients with acute basilar artery occlusions who received mechanical thrombectomy were included from January 2015 to December 2021. Patients received either first-line contact aspiration or stentriever mechanical thrombectomy. Primary clinical and safety outcomes were 90-day functional independence measured by a modified Rankin Scale score of 0 to 3 and symptomatic intracranial hemorrhage, respectively. Secondary outcomes included puncture-recanalization times, first-pass recanalization rates, crossovers to other thrombectomy device, and neurological/hospital complications. RESULTS: Five hundred eighteen patients were included in the registry, and a total of 383 patients were included (mean [SD] age, 65.5 [15] years; 228 [59%] men) in this analysis. Of these, 219 patients were first-line ASP while 164 patients received first-line stentriever devices. Median premorbid modified Rankin Scale was zero and median presenting National Institutes of Health Stroke Scale was 17 (interquartile range, 8-26). The proportion of favorable functional outcome was similar between the 2 techniques before (47.3% versus 42.5%; odds ratio, 1.22 [95% CI, 0.78-1.89]; P=0.38) and after propensity matching (odds ratio, 1.46 [95% CI, 0.85-2.49]; P=0.17). In our propensity-matched cohorts, puncture-recanalization times (18 versus 52 minutes; P<0.01) favored first-line ASP; however, first-pass recanalization rates (43.5% versus 44.5%; P=0.90) were similar between groups. First-line ASP was associated with higher rates of crossover (22% versus 6%; P<0.01), whereas stentriever was associated with higher rates of symptomatic intracranial hemorrhage (9.8% versus 3.4%; P=0.04). CONCLUSIONS: First-line ASP and stentriever methods demonstrated similar functional outcome and recanalization rates. Stentriever methods were associated with higher rates of symptomatic intracranial hemorrhage, whereas ASPs were associated with higher rates of crossover to alternative technique in patients with acute basilar occlusions.


Subject(s)
Basilar Artery , Ischemic Stroke , United States , Male , Humans , Aged , Female , Retrospective Studies , Thrombectomy/adverse effects , Intracranial Hemorrhages/epidemiology , Intracranial Hemorrhages/etiology , Registries
14.
Interv Neuroradiol ; : 15910199231196329, 2023 Aug 29.
Article in English | MEDLINE | ID: mdl-37642975

ABSTRACT

BACKGROUND: Neuroendovascular therapies involve an everchanging landscape of new technologies. Understanding the real-world timeframe of adaptation of such technologies can provide further guidance on mechanisms that could be employed to shorten the duration necessary for the widespread use of proven therapies. In this study, we aim to investigate the trends in the use of neuroendovascular technologies, utilizing the sales of neuroendovascular devices, as a proxy for procedural volume. METHODS: Utilizing a device sales data registry from the Decision Resources Group, a healthcare research and consulting company, we examined trends in the sales of devices utilized in cerebrovascular thrombectomy, cerebral aneurysm treatment, and carotid stenting from the same 407 reporting hospitals in the United States between January 1, 2015, and January 1, 2020. Device sales per year were plotted as both the total number of devices sold per year as well as the percent of total device sales when compared against at least one other device. The Cochran-Armitage test for trend was performed when comparing at least two devices to each other. Analyses were performed using RStudio Version 1.1.456 (https://rstudio.com). RESULTS: Between 2015 and 2020, there was a significant increase in the use of flow-diverting stents as well as nondiverting stents utilized for coil assistance. However, the total number of coils utilized over the years has declined. In terms of stroke therapy, between 2015 and 2020, there was a trend of increased use of both aspiration catheters as well as stent retrievers, which plateaued in 2020. The number of stents used for carotid procedures has also been gradually increasing over time. CONCLUSION: Our study demonstrates an increase in the use of flow-diverting stents, nondiverting stents, carotid stents, and reperfusion devices for acute ischemic stroke intervention between 2015 and 2020. Coil use for aneurysmal treatment has declined.

15.
Int J Hyperthermia ; 40(1): 2237218, 2023.
Article in English | MEDLINE | ID: mdl-37495214

ABSTRACT

OBJECTIVE: This study investigated the effect of various histotripsy dosages on tumor cell kill and associated bleeding in two murine brain tumor models (glioma [Gl261] and lung metastasis [LL/2-Luc2]). METHODS AND MATERIALS: GL261 or LL/2-Luc2 cells were cultured and implanted into the brains of C57BL/6 mice. Histotripsy (1-cycle pulses, 5 Hz PRF, 30 MPa-P) was performed using a 1 MHz transducer for five different dosages for each cell line: 5, 20 or 200 pulses per location (PPL) at a single treatment point, or 5 or 10-20 PPL at multiple treatment points. MRI, bioluminescence imaging and histology were used to assess tumor ablation and treatment effects within 4-6 h post-treatment. RESULTS: All treatment groups resulted in a reduction of BLI intensity for the LL/2-Luc2 tumors, with significant signal reductions for the multi-point groups. The average pre-/post-treatment BLI flux (photons/s, ×108) for the different treatment groups were: 4.39/2.19 (5 PPL single-point), 5.49/1.80 (20 PPL single-point), 3.86/1.73 (200 PPL single-point), 2.44/1.11 (5 PPL multi-point) and 5.85/0.80 (10 PPL multi-point). MRI and H&E staining showed increased tumor damage and hemorrhagic effects with increasing histotripsy dose for both GL261 and LL/2-Luc2 tumors, but the increase in tumor damage was diminished beyond 10-20 PPL for single-point treatments and outweighed by increased hemorrhage. In general, hemorrhage was confined to be within 1 mm of the treatment boundary for all groups. CONCLUSIONS: Our results suggest that a lower number of histotripsy pulses at fewer focal locations can achieve substantial tumor kill while minimizing hemorrhage.


Subject(s)
Brain Neoplasms , High-Intensity Focused Ultrasound Ablation , Animals , Mice , High-Intensity Focused Ultrasound Ablation/methods , Mice, Inbred C57BL , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/therapy , Cell Line , Brain
16.
Ultrasound Med Biol ; 49(8): 1882-1891, 2023 08.
Article in English | MEDLINE | ID: mdl-37277304

ABSTRACT

OBJECTIVE: Currently, there is a knowledge gap in our understanding of the magnetic resonance imaging (MRI) characteristics of brain tumors treated with histotripsy to evaluate treatment response as well as treatment-related injuries. Our aim was to bridge this gap by investigating and correlating MRI with histological analysis after histotripsy treatment of mouse brain with and without brain tumors and evaluating the evolution of the histotripsy ablation zone on MRI over time. METHODS: An eight-element, 1 MHz histotripsy transducer with a focal distance of 32.5 mm was used to treat orthotopic glioma-bearing mice and normal mice. The tumor burden at the time of treatment was ∼5 mm3. T2, T2*, T1 and T1-gadolinium (Gd) MR images and histology of the brain were acquired on days 0, 2 and 7 for tumor-bearing mice and days 0, 2, 7, 14, 21 and 28 post-histotripsy for normal mice. RESULTS: T2 and T2* sequences most accurately correlated with histotripsy treatment zone. The treatment-induced blood products, T1 along with T2, revealed blood product evolution from oxygenated, de-oxygenated blood and methemoglobin to hemosiderin. And T1-Gd revealed the state of the blood-brain barrier arising from the tumor or histotripsy ablation. Histotripsy leads to minor localized bleeding, which resolves within the first 7 d as evident on hematoxylin and eosin staining. By day 14, the ablation zone could be distinguished only by the macrophage-laden hemosiderin, which resides around the ablation zone, rendering the treated zone hypo-intense on all MR sequences. CONCLUSION: These results provide a library of radiological features on MRI sequences correlated to histology, thus allowing for non-invasive evaluation of histotripsy treatment effects in in vivo experiments.


Subject(s)
Brain Neoplasms , Glioma , Mice , Animals , Hemosiderin , Magnetic Resonance Imaging/methods , Glioma/diagnostic imaging , Glioma/therapy , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/therapy , Brain/diagnostic imaging
17.
World Neurosurg X ; 19: 100181, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37026086

ABSTRACT

Background: Guidelines for determining shunt dependence after aneurysmal subarachnoid hemorrhage (aSAH) remain unclear. We previously demonstrated change in ventricular volume (VV) between head CT scans taken pre- and post-EVD clamping was predictive of shunt dependence in aSAH. We sought to compare the predictive value of this measure to more commonly used linear indices. Methods: We retrospectively analyzed images of 68 patients treated for aSAH who required EVD placement and underwent one EVD weaning trial, 34 of whom underwent shunt placement. We utilized an in-house MATLAB program to analyze VV and supratentorial VV (sVV) in head CT scans obtained before and after EVD clamping. Evans' index (EI), frontal and occipital horn ratio (FOHR), Huckman's measurement, minimum lateral ventricular width (LV-Min.), and lateral ventricle body span (LV-Body) were measured using digital calipers in PACS. Receiver operating curves (ROC) were generated. Results: Area under the ROC curves (AUC) for the change in VV, sVV, EI, FOHR, Huckman's, LV-Min., and LV-Body with clamping were 0.84, 0.84, 0.65, 0.71.0.69, 0.67, and 0.66, respectively. AUC for post-clamp scan measurements were 0.75, 0.75, 0.74, 0.72, 0.72, 0.70, and 0.75, respectively. Conclusion: VV change with EVD clamping was more predictive of shunt dependence in aSAH than change in linear measurements with clamping and all post-clamp measurements. Measurement of ventricular size on serial imaging with volumetrics or linear indices utilizing multidimensional data points may therefore be a more robust metric than unidimensional linear indices in predicting shunt dependence in this cohort. Prospective studies are needed for validation.

18.
Nat Struct Mol Biol ; 30(4): 502-511, 2023 04.
Article in English | MEDLINE | ID: mdl-36997760

ABSTRACT

Heterotrimeric G proteins serve as membrane-associated signaling hubs, in concert with their cognate G-protein-coupled receptors. Fluorine nuclear magnetic resonance spectroscopy was employed to monitor the conformational equilibria of the human stimulatory G-protein α subunit (Gsα) alone, in the intact Gsαß1γ2 heterotrimer or in complex with membrane-embedded human adenosine A2A receptor (A2AR). The results reveal a concerted equilibrium that is strongly affected by nucleotide and interactions with the ßγ subunit, the lipid bilayer and A2AR. The α1 helix of Gsα exhibits significant intermediate timescale dynamics. The α4ß6 loop and α5 helix undergo membrane/receptor interactions and order-disorder transitions respectively, associated with G-protein activation. The αN helix adopts a key functional state that serves as an allosteric conduit between the ßγ subunit and receptor, while a significant fraction of the ensemble remains tethered to the membrane and receptor upon activation.


Subject(s)
GTP-Binding Protein alpha Subunits, Gs , Heterotrimeric GTP-Binding Proteins , Humans , Models, Molecular , GTP-Binding Protein alpha Subunits, Gs/metabolism , Protein Conformation , Heterotrimeric GTP-Binding Proteins/metabolism , GTP-Binding Protein alpha Subunits/chemistry , GTP-Binding Protein alpha Subunits/metabolism , Protein Binding
19.
World Neurosurg ; 170: e529-e541, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36402305

ABSTRACT

BACKGROUND: Ehlers-Danlos type IV or vascular Ehlers-Danlos syndrome (vEDS) is a rare inherited disorder characterized by profound vascular fragility resulting from defective production of type III procollagen. Cerebrovascular diseases including spontaneous dissections, cerebral aneurysms, and cavernous carotid fistulae are common. Endovascular therapies in this patient population are known to be higher risk, although many studies (before 2000) involved older techniques and equipment. The purpose of this study is to investigate the safety and efficacy of modern neuroendovascular techniques in the treatment of cerebrovascular diseases in patients with vEDS. METHODS: We combined a multi-institutional retrospective case series at 3 quaternary-care centers with a systematic literature review of individual case reports and case series spanning 2000-2021 to evaluate the safety and efficacy of neuroendovascular procedure in patients with vEDS with cerebrovascular diseases. RESULTS: Fifty-nine patients who underwent 66 neuroendovascular procedures were evaluated. Most of the patients had direct cavernous carotid fistulas (DCCF). Neuroendovascular procedures had a 94% success rate, with a complication rate of 30% and a mortality of 7.5%. CONCLUSIONS: Neuroendovascular procedures can be performed with a high rate of success in the treatment of cerebrovascular diseases in patients with vEDS, although special care is required because complication rates and mortality are high. Access site and procedure-related vascular injuries remain a significant hurdle in treating vEDS with cerebrovascular diseases, even with modern techniques.


Subject(s)
Cavernous Sinus , Ehlers-Danlos Syndrome, Type IV , Ehlers-Danlos Syndrome , Intracranial Aneurysm , Humans , Retrospective Studies , Ehlers-Danlos Syndrome/complications , Ehlers-Danlos Syndrome/surgery , Intracranial Aneurysm/surgery , Intracranial Aneurysm/complications , Multicenter Studies as Topic
20.
Interv Neuroradiol ; 29(6): 683-690, 2023 Dec.
Article in English | MEDLINE | ID: mdl-35673710

ABSTRACT

BACKGROUND: Middle meningeal artery (MMA) embolization is an apparently efficacious minimally invasive treatment for nonacute subdural hematomas (NASHs), but how different embolisates affect outcomes remains unclear. Our objective was to compare radiographic and clinical outcomes after particle or liquid MMA embolization. METHODS: Patients who had MMA embolization for NASH were retrospectively identified from a multi-institution database. The primary radiographic and clinical outcomes-50% NASH thickness reduction and need for surgical retreatment within 90 days, respectively-were compared for liquid and particle embolizations in patients treated 1) without surgical intervention (upfront), 2) after recurrence, or 3) with concomitant surgery (prophylactic). RESULTS: The upfront, recurrent, and prophylactic subgroups included 133, 59, and 16 patients, respectively. The primary radiographic outcome was observed in 61.8%, 61%, and 72.7% of particle-embolized patients and 61.3%, 55.6%, and 20% of liquid-embolized patients, respectively (p = 0.457, 0.819, 0.755). Hazard ratios comparing time to reach radiographic outcome in the particle and liquid groups or upfront, recurrent, andprophylactic timing were 1.31 (95% CI 0.78-2.18; p = 0.310), 1.09 (95% CI 0.52-2.27; p = 0.822), and 1.5 (95% CI 0.14-16.54; p = 0.74), respectively. The primary clinical outcome occurred in 8.0%, 2.4%, and 0% of patients who underwent particle embolization in the upfront, recurrent, and prophylactic groups, respectively, compared with 0%, 5.6%, and 0% who underwent liquid embolization (p = 0.197, 0.521, 1.00). CONCLUSIONS: MMA embolization with particle and liquid embolisates appears to be equally effective in treatment of NASHs as determined by the percentage who reach, and the time to reach, 50% NASH thickness reduction and the incidence of surgical reintervention within 90 days.


Subject(s)
Embolization, Therapeutic , Hematoma, Subdural, Chronic , Non-alcoholic Fatty Liver Disease , Humans , Hematoma, Subdural, Chronic/therapy , Meningeal Arteries/diagnostic imaging , Retrospective Studies , Non-alcoholic Fatty Liver Disease/therapy , Treatment Outcome , Embolization, Therapeutic/methods
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