Contrast Staining Research Articles

Characteristics and outcomes of patients with stent implantation for coronary artery lesions caused by Kawasaki disease - insights from second-generation stent implantation.

Adult Kawasaki patients may require intervention for occlusive coronary artery disease. Some adverse effects of first-generation drug-eluting stent implantation with sirolimus have been reported in this population. A total of nine lesions in eight (seven males, one female) patients who underwent stent implantations in this population between 2000 and 2021 were reviewed. The age at stent implantation ranged from 31 to 47 years, with a median of 37 years. There were six lesions treated by primary percutaneous transluminal coronary interventions, and three by elective procedures. A coronary aneurysm was found in two lesions, and coronary artery calcification was found in all culprit lesions. The numbers of everolimus-eluting stents, sirolimus-eluting stents and bare metal stents were six, two, and one, respectively. As anti- thrombotic therapy, aspirin, clopidogrel, and prasugrel were given to four, three, and one, respectively. Warfarin was given to five patients. The follow-up ranged from 2 to 12 years, with a median of 4 years. Follow-up angiograms were performed for eight lesions, at 2 to 38 months, with a median of 11 months. The patency of the target vessel was confirmed in all eight vessels. Slight malapposition, and peri-stent contrast staining were found in two lesions each. Acute coronary syndrome due to coronary artery lesions caused by Kawasaki disease occurred, even in lesions without any apparent coronary artery aneurysms. In our study, we show safe and efficacious placement of second-generation stent without adverse effects during the short-term follow-up, but long-term follow-up is needed to determine the efficacy and complication.

Deciphering the Refined Musculature of the Brow Area in Asians by Micro-Computed Tomography.

The brow area is an important aesthetic unit. Accurate anatomical understanding of the brow is important for clinical treatments related to this region. Due to the complexity of the brow area and limitations of methods, there are still some controversies regarding its musculature description. This article aims to reveal the detailed musculature using micro-computed tomography (micro-CT) combined with histological staining. Eight fresh cadaver (16 hemifaces) were obtained. Eight hemifaces were processed with phospho-tungstic acid contrast staining for micro-CT scanning and reconstruction. The other corresponding 8 hemifaces were prepared with Masson staining. The orbicularis oculi muscle (OOM), frontalis muscle (FM), depressor supercilii (DS) and procerus muscle (PM) were situated superficially. The FM terminated and connected with its antagonistic muscles at 2-5 mm above the brow but the fusion line descended in lateral third. The corrugator supercilii muscle (CSM) originated from the periosteum, extending laterally and superficially. During its course, it mainly penetrated the FM. CSM had broad subcutaneous insertion, covering about 77.9% ± 7.5% of the hairy brow. CSM fibers connected to the subcutaneous fiber septa to directly transmit contraction force. The soft tissue on the lateral side of the brow was looser than that on the medial side. Our study deepens the understanding of the precise anatomy of the brow area and helps guide clinical practice.

TCT-398 The Impact of Intraplaque Contrast Stain Morphology on Technical Outcomes in Hydrodynamic Contrast Recanalization of Coronary Chronic Total Outcomes

TCT-398 The Impact of Intraplaque Contrast Stain Morphology on Technical Outcomes in Hydrodynamic Contrast Recanalization of Coronary Chronic Total Outcomes

Effect of remote ischemic preconditioning on cerebral circulation time in severe carotid artery stenosis: Results from the RIC-CCT trial.

In patients with severe internal carotid artery stenosis (sICAS), cerebral circulation time (CCT) is associated with cerebral hyperperfusion syndrome. This study aims to investigate the effect of remote ischemic preconditioning (RIC) on CCT in patients with sICAS. Patients are randomly assigned to the RIC group (RIC twice daily, for 2-4days before carotid artery stenting [CAS] as an adjunct to standard medical therapy) and the control group. The results show that RIC produces a significant decrease in CCT of the stenosis side (sCCT) from baseline to pre-CAS, and the occurrence of contrast staining on brain computed tomography (CT) is lower in RIC versus control group after CAS. In addition, significant changes in some serum biomarkers suggest that anti-neuroinflammation, anti-oxidative stress, protecting endothelial injury, and improving cerebral autoregulation may be associated with the effect of RIC. These findings provide supporting evidence that RIC can modulate cerebral circulation in patients with sICAS. This study was registered at ClinicalTrials.gov (NCT05451030).

In Vitro Kinetic and Thermodynamic Staining Study of Three Energy Drinks on the Restorative Charisma Composite

Abstract Aim: The research utilized charisma composite resin, a dental restorative material known for its esthetic properties, with the chemical formula 2,2-bis[p(2-hydroxy-3-methacryloxy propoxyphenyl)] propane. The primary objective of the study was to examine the overall color change (ΔE*ab) of the charisma resin after it was subjected to three distinct energy drink solutions: Monster Energy Ultra-Sunrise, Wild Tiger, and Red Bull. Further we examined the effects of temperature and time on the staining interaction and overall color difference ΔE*ab on the surface of charisma restorative resin generated by three energy drink. Materials and Methods: A microfilled Charisma Classic composite resin was used in presented comparative study selected. The prepared 144 composite disk samples (subdivided n=48) with random allocation method were used for the three energy drinks to determine the effect of temperature and time over the course of 90 days. A metallic circulator mold was prepared. Every set of 48 specimens in the energy drink was heated in a water bath for 1, 7, 30, 60, and 90 days at four different temperatures This investigation spanned various time intervals, ranging from 1 to 90 days, and encompassed four temperature levels between 283 and 310 K. One-way ANOVA was used to evaluate the mean data for color change between the energy drinks, and Tukey’s post hoc test was used for multiple comparisons, with a significance level of P < 0.05. Results: The study revealed that the rate of staining was most pronounced in the case of Wild Tiger, while it was comparatively lower for Monster Energy Ultra-Sunrise. These findings were established through an examination of the kinetic and thermodynamic behavior of surface color changes in micro-hybrid composites treated with the three energy drink solutions. Conclusions: The observed patterns aligned with the pseudo second-order model. It was observed that the Red Bull drink displayed a negative activation energy, resulting in a slower color change rate with increase in temperature. In contrast, endothermic, spontaneous, and regular staining activity was demonstrated throughout time by Monster Energy Ultra-Sunrise and Wild Tiger.

Electron microscopy of stable electrophoretic fractions of natural humic acids – the key to the understanding of their structural organization

Transmission electron microscopy (TEM) with contrast staining by uranyl acetate solution was used to study morphological differences between soil humic acids (HAs) and their A, B and C + D fractions obtained using coupling preparative low-pressure size exclusion chromatography and analytical polyacrylamide gel electrophoresis. The electrophoretic mobility of fractions varied in order C + D B A. The distribution of various morphological elements between fractions showed that large structures such as vesicle-like formations 70–150 nm long and 30–80 nm wide with clear edges were found exclusively in fraction A and occupied ~55% of the TEM image area. On the other hand, long fibrils with a length of 60–100 nm, a width of 4–6 nm and a thickness of 2–3 nm, as well as their bundles with a length of 150 nm and a diameter of 30–70 nm were identified only in the C + D fraction and occupied ~59 % area of TEM images. Smaller morphological elements such as point particles with a diameter of 2–3 nm, ring particles with a diameter of 4–6 nm, worm-shaped short particles with a length of 20–30 nm, and spheroids with a diameter of 10– 30 nm were observed in all samples, but in varying quantities. Significant morphological differences between the fractions can be explained by their composition, previously established by using a few physico-chemical methods. The ratio Car(165–108 ppm)/Calk(108–0 ppm), or aromaticity index, calculated from 13C-NMR, could be one of the indicators of the various morphological structures formation. The obtained TEM results clearly confirm the supramolecular organization of soil HAs.

Contrast Staining in Noninfarcted Tissue after Endovascular Treatment of Acute Ischemic Stroke.

Contrast staining is a common finding after endovascular treatment of acute ischemic stroke. It typically occurs in infarcted tissue and is considered an indicator of irreversible brain damage. Contrast staining in noninfarcted tissue has not been systematically investigated. We sought to assess the incidence, risk factors, and clinical significance of contrast staining in noninfarcted tissue after endovascular treatment. We conducted a retrospective review of consecutive patients who underwent endovascular treatment for anterior circulation large-vessel occlusion acute ischemic stroke. Contrast staining, defined as new hyperdensity on CT after endovascular treatment, was categorized as either contrast staining in infarcted tissue if the stained region demonstrated restricted diffusion on follow-up MR imaging or contrast staining in noninfarcted tissue if the stained region demonstrated no restricted diffusion. Baseline differences between patients with and without contrast staining in noninfarcted tissue were compared. Logistic regression was used to identify independent associations for contrast staining in noninfarcted tissue after endovascular treatment. Among 194 patients who underwent endovascular treatment for large-vessel occlusion acute ischemic stroke and met the inclusion criteria, contrast staining in infarcted tissue was noted in 52/194 (26.8%) patients; contrast staining in noninfarcted tissue, in 26 (13.4%) patients. Both contrast staining in infarcted tissue and contrast staining in noninfarcted tissue were noted in 5.6% (11/194). Patients with contrast staining in noninfarcted tissue were found to have a higher likelihood of having an ASPECTS of 8-10, to be associated with contrast staining in infarcted tissue, and to achieve successful reperfusion compared with those without contrast staining in noninfarcted tissue. In contrast staining in noninfarcted tissue regions, the average attenuation was 40 HU, significantly lower than the contrast staining in infarcted tissue regions (53 HU). None of the patients with contrast staining in noninfarcted tissue had clinical worsening during their hospital stay. The median discharge mRS was significantly lower in patients with contrast staining in noninfarcted tissue than in those without (3 versus 4; P = .018). No independent predictors of contrast staining in noninfarcted tissue were found. Contrast staining can be seen outside the infarcted tissue after endovascular treatment of acute ischemic stroke, likely attributable to the reversible disruption of the BBB in ischemic but not infarcted tissue. While generally benign, understanding its characteristics is important because it may mimic pathologic conditions such as infarcted tissue and cerebral edema.

Quantification of ischemic brain edema after mechanical thrombectomy using dual-energy computed tomography in patients with ischemic stroke

Net water uptake (NWU) is a quantitative imaging biomarker used to assess cerebral edema resulting from ischemia via Computed Tomography (CT)-densitometry. It serves as a strong predictor of clinical outcome. Nevertheless, NWU measurements on follow-up CT scans after mechanical thrombectomy (MT) can be affected by contrast staining. To improve the accuracy of edema estimation, virtual non-contrast images (VNC-I) from dual-energy CT scans (DECT) were compared to conventional polychromatic CT images (CP-I) in this study. We examined NWU measurements derived from VNC-I and CP-I to assess their agreement and predictive value in clinical outcome. 88 consecutive patients who received DECT as follow-up after MT were included. NWU was quantified on CP-I (cNWU) and VNC-I (vNWU). The clinical endpoint was functional independence at discharge. cNWU and vNWU were highly correlated (r = 0.71, p < 0.0001). The median difference between cNWU and vNWU was 8.7% (IQR: 4.5–14.1%), associated with successful vessel recanalization (mTICI2b-3) (ß: 11.6%, 95% CI 2.9–23.0%, p = 0.04), and age (ß: 4.2%, 95% CI 1.3–7.0%, p = 0.005). The diagnostic accuracy to classify outcome between cNWU and vNWU was similar (AUC:0.78 versus 0.77). Although there was an 8.7% median difference, indicating potential edema underestimation on CP-I, it did not have short-term clinical implications.

Assessment of post-thrombectomy brain hemorrhage in acute ischemic stroke with dual-energy CT: how reliable is it in clinical practice?

Acute ischemic stroke is currently among the main causes of mortality in Western countries. The current guidelines suggest different flowcharts of diagnostic work-up and treatment modalities, including endovascular thrombectomy. Immediately after intra-arterial recanalization, a brain CT scan is usually performed to assess for the presence of peri-procedural complications; in this setting, it is very hard, if possible, to differentiate blood from iodinated contrast material, which is normally present in ischemic tissue because of BBB disruption. Dual-energy CT may be used for this purpose, exploiting its ability to discriminate different materials. We retrospectively studied 44 patients with acute ischemic stroke who were treated with endovascular recanalization at San Giovanni Bosco Hospital in Turin and were then scanned with DECT technology. Subsequent scan was used as standard, since iodine from contrast staining is usually reabsorbed in 24h and blood persists longer. A χ2 test of independence was performed to examine the relationship between blood detected by DECT scan after the endovascular procedure and the presence of blood in the same areas on the following scans, with a significant result: χ2 (1, N = 37) = 10.7086, p = 0.0010. Patients with blood detected on DECT scans had a double chance of having hemorrhagic infarction in follow-up scans, (RR 2.02). The sensitivity and specificity of DECT were respectively 70% and 90%, with an overall diagnostic accuracy of 76% and a positive and negative predictive value, respectively, of 95% and 53%. Dual-energy CT scan after endovascular recanalization in ischemic stroke identifies early hemorrhagic infarction with excellent specificity and good overall diagnostic accuracy, representing a reliable diagnostic tool in everyday clinical practice.

Abstract WP124: Dual Energy Head CT Immediately Following Mechanical Thrombectomy Rarely Leads to Changes in Clinical Management

Introduction: No guidelines exist regarding imaging after mechanical thrombectomy (MT) for acute ischemic stroke (AIS). Dual Energy Head CT (DECT) can differentiate between contrast staining and intracranial hemorrhage (ICH). We obtained routine DECT for AIS patients immediately following MT. We aimed to understand the impact of DECT on clinical management. Methods: We conducted a single-center retrospective study of AIS patients who underwent MT and immediate post-procedure DECT between March 2021 and February 2023. Patients were grouped by whether or not DECT results changed management, compared to our standard post-thrombectomy protocol and as documented in clinical notes. Continuous variables were compared using Wilcoxon Rank-Sum tests, and categorical variables were compared using Chi-square tests. Results: Of 173 patients who met inclusion criteria, 13 (7.5%) had documented changes in management following DECT. Management changes included delayed anti-thrombotic administration, lowered systolic blood pressure goals, and serial imaging. There were no statistically significant differences in age, gender, initial NIHSS, ischemic core size pre-MT, or treated vessel between patients with and without a change in management. Patients with management changes were more likely to have had procedural complications, contrast staining, any ICH, and symptomatic ICH (Table). While 34 patients had ICH on DECT, this only led to a documented change in management for 11 (32.4%) patients. Conclusion: Routine DECT immediately after MT rarely changed clinical management. Immediate DECT may be reserved for patients with intraprocedural complications or those with clinical suspicion of ICH.

Abstract B010: Spatially-resolved prediction of gene expression signatures in H&amp;E whole slide images using additive multiple instance learning models

Abstract Background: Newly developed molecular technologies, such as spatial multiplexed assays and single-cell sequencing, have provided increased resolution and output for tumor analysis. However, these assays are often cost-prohibitive, making them inadequate ways to detect clinical biomarkers. In contrast, hematoxylin and eosin (H&amp;E) staining is routine for cancer diagnostics but does not provide molecular information, potentially limiting its utility in the targeted therapy era. Machine learning models could augment the information revealed by H&amp;E, potentially allowing molecular information to be inferred. Here, we describe a novel approach to predict gene expression signatures (GES) in H&amp;E-stained whole slide images (WSI) using an additive multiple instance learning (aMIL) end-to-end model (1). We present results in breast cancer predicting spatially resolved levels of a TGFb GES, a proposed biomarker for TGFb antagonists and immunotherapy. Methods: H&amp;E-stained WSI from the TCGA BRCA cohort (N=1090) were split into training (60%), validation (20%), and test (20%) sets. TGFb-CAF GES (2) were computed, and median expression cut-off on training data was used to define “high” and “low” TGFb-CAF levels. aMIL models were optimized in training data for the binary classification of TGFb-CAF levels. Top-performing model iterations were compared on the validation set, and the optimal model was deployed on the held-out test set. aMIL heatmaps were merged with PathExplore tumor microenvironment (TME) model heatmaps to characterize cell, tissue, and nuclear spatial distributions and morphology in terms of human interpretable features (HIFs). HIFs were extracted from high-importance patches (top 25% of aMIL scores) for both TGFb-CAF-high and -low. Results: Our model accurately predicted TGFb-CAF-high vs. -low BRCA samples (test AUROC=0.80). Also, model deployment on WSI provided interpretable heatmaps depicting TGFb-CAF predictions in tissue, providing spatial resolution to TGFb-CAF expression. Patches contributing most to TGFb-CAF-high prediction were enriched for cancer stroma, as well as cancer-infiltrating and stromal fibroblasts. Furthermore, significant differences in HIFs relating to fibroblast nucleus size and lymphocyte nucleus shape were observed between patches contributing most to TGFb-CAF-high and -low predictions. Conclusions: We have developed a method to predict GES with spatial resolution in H&amp;E-stained WSI. aMIL models provide exact marginal contributions of each patch towards every class prediction, allowing downstream analysis of tissue, cell, and nuclear features and providing biological interpretability not found in typical black-box models. The ability of our method to detect GES in H&amp;E-stained WSI allows complex molecular information to be detected in routine clinical specimens with spatial specificity, providing a means for GES to potentially be realized as clinical biomarkers.

High-Performance Microcomputing Tomography of Chick Embryo in the Early Stages of Embryogenesis

X-ray contrast techniques were tested on the chick embryos in early periods of embryogenesis. For contrast stain, reagents with radiopacity in various concentrations were used: silver proteinate, eosin, Lugol’s solution (I2KI), phosphomolybdic acid and phosphotungstic acid under heating at 25 °C and 40 °C and exposure for 24 and 48 h. The use of silver proteinate, eosin and I2KI in various concentrations in the contrast of the chick embryo in the early period of embryogenesis did not make it possible to obtain microtomographic results that provide reliable microstructural analysis. The most optimal and effective method of embryo staining at the HH22–HH34 embryonic stages reliably determined the staining of 1% phosphotungstic acid at 40 °C heating and exposure for 24 h. Taking into account the size of the chick embryos and their structures at the HH22–HH34 embryonic stages, the features of the development, location of organs, and the minimum permissible parameters of microtomography for obtaining high-quality and reliable results were determined by the isometric spatial resolution of 8.87 μm, X-ray voltage 50 kV, X-ray current 500 μA, and the use of filters started from Al 0.5 mm. Microtomographic results were obtained, characterized by the appearance of the chick embryo at the HH22–HH34 embryonic stages, and they visualized the locations and structures of the chick embryo organs and provided calculation of their volume and X-ray density. The results of the work open up significant prospects for using the chick embryo at the early embryonic period of embryogenesis as an alternative model for screening teratogenicity.

Prognostic value of contrast staining on dual-energy CT after endovascular therapy in acute ischemic stroke: a meta-analysis

BackgroundContrast staining (CS) on dual-energy CT (DECT) is common after endovascular therapy (EVT) in acute ischemic stroke (AIS). We performed a meta-analysis to investigate the prognostic significance of CS detected by DECT after EVT in AIS.MethodMEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science and Scopus databases were searched from inception to July 2023 for publications on the prognostic significance of CS on DECT after EVT in patients with AIS. Prognostic outcomes were hemorrhage transformation (HT) and poor functional outcome (modified Rankin Scale [mRS] Score of 3–6 at the 90-day follow-up). Data are presented as odds ratios (OR) and 95% confidence intervals (CI).ResultsEleven studies including 1123 cases of AIS were included. Pooled results indicated a higher risk of HT in patients with CS than in those without CS (OR = 2.22; 95% CI 1.41–3.51, P = 0.001; I2 = 45.4%). No association between CS and symptomatic HT was observed (OR = 2.10; 95% CI 0.64–6.95, P = 0.223; I2 = 67.3%). Moreover, there was also higher odds of poor functional outcome in patients with CS than in those without CS (OR = 2.76; 95% CI 1.53–4.97, P = 0.001; I2 = 44.9%).ConclusionsThe presence of contrast staining on DECT after EVT is associated with a higher risk of hemorrhage transformation and poor functional outcome. However, further high-quality studies with standardized processes are required to confirm these results.

Using x-ray micro computed tomography to quantify intracochlear fibrosis after cochlear implantation in a Guinea pig model

Cochlear implants (CIs) allow individuals with profound hearing loss to understand speech and perceive sounds. However, not all patients obtain the full benefits that CIs can provide and the cause of this disparity is not fully understood. One possible factor for the variability in outcomes after cochlear implantation, is the development of fibrotic scar tissue around the implanted electrode. It has been hypothesised that limiting the extent of fibrosis after implantation may improve overall CI function, and longevity of the device. Currently, histology is often used to quantify the extent of intracochlear tissue growth after implantation however this method is labour intensive, time-consuming, often involves significant user bias, and causes physical distortion of the fibrosis. Therefore, this study aimed to evaluate x-ray micro computed tomography (μCT) as a method to measure the amount and distribution of fibrosis in a guinea pig model of cochlear implantation. Adult guinea pigs were implanted with an inactive electrode, and cochleae harvested eight weeks later (n = 7) and analysed using μCT, to quantify the extent of tissue reaction, followed by histological analysis to confirm that the tissue was indeed fibrotic. Cochleae harvested from an additional six animals following implantation were analysed by μCT, before and after contrast staining with osmium tetroxide (OsO4), to enhance the visualisation of soft tissues within the cochlea, including the tissue reaction. Independent analysis by two observers showed that the quantification method was robust and provided additional information on the distribution of the response within the cochlea. Histological analysis revealed that μCT visualised dense collagenous material and new bone formation but did not capture loose, areolar fibrotic tissue. Treatment with OsO4 significantly enhanced the visible tissue reaction detected using μCT. Overall, μCT is an alternative and reliable method that can be used to quantify the extent of the CI-induced intracochlear tissue response and will be a useful tool for the in vivo assessment of novel anti-fibrotic treatments.

Transmission electron microscopy of electrophoretic humic acids fractions obtained by coupling size exclusion chromatography-polyacrylamide gel electrophoresis: The next step to understanding structural organization of soil humic matter

The transmission electron microscopy (TEM) with contrast staining by uranyl acetate solution was used to study morphological differences between soil humic acids (HAs) and their A, B and C + D fractions obtained using coupling preparative low-pressure size exclusion chromatography and analytical polyacrylamide gel electrophoresis. The electrophoretic mobility of fractions varied in order C + D > B > A. The distribution of various morphological elements between the bulk HAs and their fractions clearly showed that larger structures, such as smeared drops (70–150 nm long), were formed exclusively in fraction A, whereas elongated fibers (60–100 nm long) and their bundles (>150 nm long) were found only in fraction C + D. Smaller morphological elements such as point particles (2–3 nm in diameter), ring particles (4–6 nm in diameter) with hole in the center, worm-like short particles (20–30 nm long) and spheroids (10–30 nm in diameter) were observed in all samples, but in varying quantities. Significant morphological differences between the samples can be explained by their contrasting properties obtained earlier by different physical–chemical methods. The ratio Car(165–108 ppm)/Calk (108–0 ppm) or aromaticity derived from 13C NMR data appears to be one of the indicators for the formation of different morphological structures. This study provides the new information about morphological structures of soil organic matter that are consistent with the formation of different supramolecular aggregates, probably controlled by the association of smaller ring particles. The data obtained can clarify the role of humic acids in the environment and their involvement in physical–chemical processes in soils.

Hemorrhagic Transformation Assessment Based on Dual Energy CT of Immediately and Twenty-Four Hours after Endovascular Thrombectomy for Acute Ischemic Stroke.

Dual-energy CT (DECT) shows good performance in differentiating hemorrhage from contrast staining (CS). However, no guidelines have standardized the post-endovascular thrombectomy (EVT) examination time. We evaluated the value of performing DECT immediately and 24 h post-EVT in the diagnosis and prediction of hemorrhagic transformation (HT). Two readers evaluated simulated conventional CT (sCCT) images compared with a second reading with DECT, establishing the diagnosis of HT immediately and 24 h post-EVT. Another reader's diagnosis 2-7 days post-EVT using non-contrast CT was identified as the final diagnostic criteria. DECT performed immediately and 24 h post-EVT changed 22.4% (52/232) and 12.5% (29/232) of sCCT-based HT diagnoses, respectively (χ2 = 10.7, p < 0.05). The sensitivity, negative predictive value (NPV), and accuracy of DECT performed immediately post-EVT for predicting the final diagnosis of HT were 33.6%, 58.9%, and 65.9%, respectively, whereas those for DECT performed 24 h post-EVT were 82.4%, 84.3%, and 90.9%, respectively (χ2 = 58.0, χ2 = 42.9, χ2 = 13.6; p < 0.05). The specificity and positive predictive value were both 100.0%. Delayed HT occurred in 50.0% (78/156) and 42.2% (19/45) of patients with CS diagnosed immediately and 24 h post-EVT, respectively. DECT performed immediately post-EVT changed a greater proportion of real-time HT diagnoses, whereas that performed 24 h post-EVT had higher sensitivity, NPV, and accuracy in predicting the final diagnosis of HT. A substantial proportion of patients with CS diagnosed at these two post-EVT timepoints subsequently developed delayed HT.

The clinical utility of dual-energy CT in post-thrombectomy care: Part 2, the predictive value of contrast density and volume for delayed hemorrhagic transformation

ObjectivesDual-energy CT allows differentiation between blood and iodinated contrast. This study aims to determine the predictive value of contrast density and volume on post-thrombectomy dual-energy CT for delayed hemorrhagic transformation and its impact on 90-day outcomes. Materials and MethodsA retrospective analysis was performed on patients who underwent thrombectomy for anterior circulation large-vessel occlusion at a comprehensive stroke center from 2018-2021. Per institutional protocol, all patients underwent dual-energy CT immediately post-thrombectomy and MRI or CT 24 hours afterward. The presence of hemorrhage and contrast staining was evaluated by dual-energy CT. Delayed hemorrhagic transformation was determined by 24-hour imaging and classified into petechial hemorrhage or parenchymal hematoma using ECASS III criteria. Univariable and multivariable analyses were performed to determine predictors and outcomes of delayed hemorrhagic transformation. ResultsOf 97 patients with contrast staining and without hemorrhage on dual-energy CT, 30 and 18 patients developed delayed petechial hemorrhage and delayed parenchymal hematoma, respectively. On multivariable analysis, delayed petechial hemorrhage was predicted by anticoagulant use (OR,3.53;p=0.021;95%CI,1.19-10.48) and maximum contrast density (OR,1.21;p=0.004;95%CI,1.06-1.37;per 10 HU increase), while delayed parenchymal hematoma was predicted by contrast volume (OR,1.37;p=0.023;95%CI,1.04-1.82;per 10 mL increase) and low-density lipoprotein (OR,0.97;p=0.043;95%CI,0.94-1.00;per 1 mg/dL increase). After adjusting for potential confounders, delayed parenchymal hematoma was associated with worse functional outcomes (OR,0.07;p=0.013;95%CI,0.01-0.58) and mortality (OR,7.83;p=0.008;95%CI,1.66-37.07), while delayed petechial hemorrhage was associated with neither. ConclusionContrast volume predicted delayed parenchymal hematoma, which was associated with worse functional outcomes and mortality. Contrast volume can serve as a useful predictor of delayed parenchymal hematoma following thrombectomy and may have implications for patient management.

Gene expression detection in developing mouse tissue using in situ hybridization and µCT imaging

High resolution and noninvasiveness have made soft-tissue X-ray microtomography (µCT) a widely applicable three-dimensional (3D) imaging method in studies of morphology and development. However, scarcity of molecular probes to visualize gene activity with µCT has remained a challenge. Here, we apply horseradish peroxidase-assisted reduction of silver and catalytic gold enhancement of the silver deposit to insitu hybridization in order to detect gene expression in developing tissues with µCT (here called GECT, gene expression CT). We show that GECT detects expression patterns of collagen type II alpha 1and sonic hedgehogin developing mouse tissues comparably with an alkaline phosphatase-based detection method. After detection, expression patterns are visualized with laboratory µCT, demonstrating that GECT is compatible with varying levels of gene expression and varying sizes of expression regions. Additionally, we show that the method is compatible with prior phosphotungstic acid staining, a conventional contrast staining approach in µCT imaging of soft tissues. Overall, GECT is a method that can be integrated with existing laboratory routines to obtain spatially accurate 3D detection of gene expression.

Deep learning-based approach to predict multiple genetic mutations in colorectal and lung cancer tissues using hematoxylin and eosin-stained whole-slide images.

1549 Background: The presence of genetic mutations is a vital prognostic in many types of cancer. However, genomic testing is expensive and challenging to perform. In contrast, hematoxylin and eosin (H&amp;E) staining is relatively inexpensive and straightforward. Thus, in this study, we propose a method of predicting the presence of genetic mutations using H&amp;E-stained whole-slide images (WSIs). Methods: We divided each H&amp;E–stained WSI into small pieces or “patches.” We used a deep learning model to classify each patch based on the presence of tumor-containing regions. We then extracted image features from each tumor-containing patch using a deep learning-based feature extractor. We created image features for the entire WSI by concatenating the features of the patches. We then trained genetic mutation classification models using the WSI features as the input and the presence or absence of genetic mutations as the output. Finally, we evaluated the performance of these models using the area under the receiver operating characteristic curve (AUC). Results: First, we evaluated our methods using The Cancer Genome Atlas (TCGA) colorectal cancer dataset. We used H&amp;E–stained WSIs and data associated with Microsatellite Instability ( MSI) and BRAF gene mutations, which are directly relevant to therapeutic strategies, obtained from an independent clinical cohort of 566 patients with TCGA colon and rectum adenocarcinoma. We divided the data into training, validation, and test splits, comprising 367, 90, and 109 patients, respectively. We used the training and validation splits for model training and selection, and the test split for model evaluation. The AUC values of the classification models and associated 95% confidence intervals (CIs) were 0.721 (CI = 0.572–0.870) for MSI and 0.712 (CI = 0.547–0.877) for BRAF gene mutations. We also applied our approach to MUC16, KRAS, and ALK mutations using the TCGA lung cancer dataset. We divided 909 TCGA lung adenocarcinoma and lung squamous cell carcinoma patients into training, validation, and test splits, comprising 582, 146, and 181 patients, respectively. In contrast with those of the colorectal dataset, WSI image features were generated using all patches. The AUC values on the test splits were 0.897 (CI = 0.85–0.95) for MUC16, 0.845 (CI = 0.75–0.94) for KRAS, and 0.756 (CI = 0.57–0.94) for ALK mutations. Conclusions: We proposed an approach to predict the presence of genetic mutations using only H&amp;E–stained WSIs and evaluated its performance using colorectal and lung cancer datasets. Our model has the potential to predict the presence of certain genetic mutations with superior performance. These predictions can be used to improve the accuracy of prognostic prediction using WSIs alone.

Novel deep learning–based prognostic prediction model for colorectal cancer using hematoxylin and eosin–stained whole slide images.

3119 Background: Previous studies have shown that the presence or absence of genetic mutations is critical for colorectal cancer prognosis. However, genomic testing can be expensive and difficult to perform on all samples. In contrast, hematoxylin and eosin (H&amp;E) staining is relatively inexpensive and can be performed on all tissue specimens. In this study, we designed a novel prognostic method using spatial image features extracted from H&amp;E–stained whole slide images (WSIs) and genetic mutation prediction neural networks. Methods: We obtained H&amp;E–stained WSIs and data on Microsatellite Instability ( MSI), BRAF, TTN and APC gene mutations from a clinical cohort of 548 patients with The Cancer Genome Atlas (TCGA) Colon adenocarcinoma and rectum adenocarcinoma. We divided them into training (n=361), validation (n=90), and test (n=115) groups. Classification models were trained to predict the presence or absence of MSI, BRAF, TTN, and APC mutations. The model input comprised features of the H&amp;E–stained WSIs, as obtained via a deep learning–based feature extractor. All resultant models were incorporated into a prognostic model (overall survival: &gt; 60 months (low risk)/&lt; 60 months (high risk)). Our prognostic model’s performance was evaluated against TCGA colorectal dataset, and a survival analysis was performed on the model using the Kaplan–Meier method. Finally, we compared our model’s performance with the end–to–end prognostic prediction of a convolutional neural network (CNN) that also used H&amp;E–stained WSIs as input and provided prognostic prediction as output. Results: Our deep learning–based prognostic prediction model achieved an AUC score of 0.834 with a 95% confidence interval (CI) of 0.734–1.000 alongside TCGA dataset; the survival analysis compared the survival distributions of low–risk and high–risk groups, as predicted by our model; a p–value &lt; 0.01 was obtained. The model could classify low– and high–risk patients and accurately predict patient status as alive (low risk) or deceased (high risk) at 60 months. In contrast, the CNN–based model achieved an AUC score of only 0.502 (95% CI: 0.315–0.690) on the same TCGA dataset, and the p–value obtained for it under the Kaplan–Meier log–rank test was greater than 0.5. The CNN–based method was unable to distinguish between low– and high–risk patients, confirming that our method using spatial imaging features extracted from WSIs was a more effective approach. Conclusions: We developed a novel prognostic prediction method using spatial image features extracted from WSIs and genetic mutation prediction neural networks. Our results demonstrated the advantage of using image features over gene mutation data for prognostic prediction in colorectal cancer patients.