Tomography Scan Research Articles

Realization of high-end PET devices that assist conventional PET devices in improving image quality via diffusion modeling

PurposeThis study aimed to implement high-end positron emission tomography (PET) equipment to assist conventional PET equipment in improving image quality via a distribution learning-based diffusion model.MethodsA diffusion model was first trained on a dataset of high-quality (HQ) images acquired by a high-end PET device (uEXPLORER scanner), and the quality of the conventional PET images was later improved on the basis of this trained model built on null-space constraints. Data from 180 patients were used in this study. Among them, 137 patients who underwent total-body PET/computed tomography scans via a uEXPLORER scanner at the Sun Yat-sen University Cancer Center were retrospectively enrolled. The datasets of 50 of these patients were used to train the diffusion model. The remaining 87 cases and 43 PET images acquired from The Cancer Imaging Archive were used to quantitatively and qualitatively evaluate the proposed method. The nonlocal means (NLM) method, UNet and a generative adversarial network (GAN) were used as reference methods.ResultsThe incorporation of HQ imaging priors derived from high-end devices into the diffusion model through network training can enable the sharing of information between scanners, thereby pushing the limits of conventional scanners and improving their imaging quality. The quantitative results showed that the diffusion model based on null-space constraints produced better and more stable results than those of the methods based on NLM, UNet and the GAN and is well suited for cross-center and cross-device imaging.ConclusionA diffusion model based on null-space constraints is a flexible framework that can effectively utilize the prior information provided by high-end scanners to improve the image quality of conventional scanners in cross-center and cross-device scenarios.

Health-Related Quality of Life During Carfilzomib-Lenalidomide-Dexamethasone Consolidation: Findings From the Multiple Myeloma CONPET Study.

In the CONPET study, multiple myeloma patients with abnormal 18FDG positron emission/computed tomography scan after upfront autologous stem cell transplantation were treated with four cycles of carfilzomib-lenalidomide-dexamethasone (KRd). Side effect registrations show that carfilzomib might cause dyspnea, cough, respiratory tract infections, and heart failure. The aims were to investigate patient-reported shortness of breath and dyspnea during KRd consolidation. To assess shortness of breath, patients completed the Functional Assessment of Cancer Therapy-Pulmonary Symptom Index (FACT-PSI) and the EORTC QLQ-C30 to assess dyspnea. Shortness of breath was defined as decrease in FACT-PSI score or starting/increasing diuretic drugs. Mixed effect logistic regression was used for the effect analysis. Linear mixed model and clinical relevance were used to investigate dyspnea. A total of 50 patients were included, median age 62 years (interquartile range 54-67). 17% reported shortness of breath at Day 15 Cycles 1-4 versus 11% at Day 1 Cycles 2-4, Cycle 4 Day 29, and 1 month posttreatment (p-value 0.048). Compared with baseline, patients reported significant, and clinically relevant worsening in dyspnea during consolidation. Our study confirmed earlier findings of carfilzomib causing shortness of breath during KRd administration and revealed dyspnea during consolidation compared to baseline. Clinicaltrials.gov: NCT03314636, EudraCT: 2017-000586-72.

Assessment of failure risks during C2 vertebra pedicle screw insertion using three-dimensional computed tomography angiography analysis: the role of high-riding vertebral artery and narrow pedicles.

Cervical fixation is a common treatment for conditions like vertebral fractures, osteosarcoma, osteomyelitis, arthritis, and congenital disorders. The study was designed to assess the occurrence of high-riding vertebral artery (HRVA), narrow C2 pedicles (NC2P) and ponticulus posticus (PP), which pose risks of injuring vertebral artery (VA) during screw placement in cervical fixation procedures. The study examined the prevalence of HRVA, NC2P and PP in 382 pedicle sides of the C2 vertebra using computed tomographic angiography scans. Specific measurements were taken, including the internal height (C2InH), and isthmus height (C2IsH) of C2, as well as NC2P width. HRVA was identified by specific measurements: C2IsH of ≤ 5mm and/or C2InHof ≤ 2mm. NC2P was defined as NC2P width ≤ 4mm. The reliability between observers and within the same observer, along with the consistency across different software, was assessed. At least one HRVA was found in 9.6% of patients and at least one NC2P in 13% of patients. Females demonstrated higher rates of HRVA and NC2Ps on the left side, with right-side figures at 10.5% and 11.7% for HRVA and NC2Ps respectively, and left side figures at 14.1% for both. Males exhibited a reserve pattern, with higher rates on the right side, marked by 10.3% HRVA and 15% NC2Ps, compared to 5.6% and 11.3% on the left. Furthermore, males showed a significantly higher occurrence of NC2Ps over HRVA on both sides. The presence of PP with NC2Ps detected in 44% of cases, and with HRVA in 16% of cases, a difference found to be statistically significant. The digital models incorporating HRVA, NC2P, and PP facilitated a comprehensive analysis of the VA pattern, assessment of the virtual screw trajectory line for VA pedicles, and the designation of specific regions during the procedure, ensuring increased safety planning instrumentation.

Treatment Options for Coronal Plane Fractures of the Lunate in Kienböck Disease.

The treatment for Kienböck disease varies widely based on the status of the lunate. To date, there is no consensus regarding the optimal treatment for patients with coronal plane fractures of the lunate, or Lichtman Stage IIIC. Therefore, the purpose of this study was to assess whether coronal plane fractures of the lunate in Kienböck disease healed after surgical intervention, and to determine the outcomes after surgical fixation of the lunate compared with treatment with salvage procedures. A retrospective review of 36 patients with Lichtman IIIC Kienböck disease was conducted. Patients were classified into lunate reconstruction (vascularized bone graft [VBG] or non-VBG) or salvage procedures (proximal row carpectomy [PRC] or limited fusion). Preoperative and postoperative visual analog scale (VAS) pain, range of motion, grip strength, and Mayo Wrist Score (MWS) were analyzed. Radiographs and computed tomographic scans were reviewed for Lichtman stage, fracture location, union, modified carpal height ratio, Stahl index, and radioscaphoid angle. Thirteen patients underwent lunate reconstruction, 13 underwent limited fusion, and 10 underwent PRC. The overall union rate was 45% after lunate reconstruction, with average time to union of 7 months. There were no differences in union rates between VBG and non-VBG. All 3 groups experienced improvement in their postoperative grip strength and MWS. There were no statistically significant differences in preoperative to postoperative changes in clinical outcome measures between the 3 cohorts; however, when we compared lunate reconstruction with all patients who underwent salvage procedures (limited carpal fusion and PRC), we noted the latter had improved functional outcomes (P = .019). Four patients (31%) in the reconstruction cohort and 2 patients (8%) in the limited carpal fusion group required reoperation at latest follow-up. Union rate of coronal plane fractures in Kienböck disease remains variable. While the proportion of patients requiring reoperation was higher in the reconstruction group, all groups of patients experienced improvement in their clinical outcomes, without a significant difference between cohorts.

Characterization of Inclusion Size Distributions in a Large Forged Shaft Using X‐ray Micro‐Computed Tomography Imaging

The presence of nonmetallic inclusions in steel considerably affects the material's properties. This study investigates these effects by sampling six locations along the radial direction of a large forged shaft to analyze the distribution characteristics of inclusions. Scanning electron microscopy and optical microscopy are used to identify the types and morphologies of the inclusions. X‐ray micro‐computed tomography scanning provides detailed distribution data, including the length, width, equivalent diameter, and shape of the inclusions. This approach allows for a comprehensive understanding of the radial distribution characteristics of inclusions in the forged shaft. The results reveal that both the quantity and size of inclusions in the large forged shaft increase progressively from the edge toward the center. Additionally, the fatigue strength is estimated based on the inclusion distribution at various locations. The prediction shows a relative error exceeding 15%, indicating that the heterogeneity of the components considerably affects their fatigue performance. Finally, a novel method for predicting the maximum inclusion size within the heterogeneous large forged shaft is introduced.

Volumetric Imaging From Raman Perspective: Review and Prospect

AbstractVolumetric imaging, which supports quantitative and comprehensive assessment of a 3D sample from an entire volume, has attracted tremendous attention in biomedical research. Fluorescence imaging techniques, such as optical sectioning and light sheet microscopy, enable to reconstruct the 3D distribution of chemicals within a sample. However, current methods rely on exogenous labels, from which considerable perturbation may be introduced in living systems. Raman imaging offers a feasible solution to visualize components in biological samples in a label‐free manner. Besides, the integration of Raman microscopy with 3D approaches will benefit the research of biomedical samples on novel devices, which is dominated by the strongly enhanced spatial resolution, imaging speed, and overall field of view as well as complemented more details of samples. In this overview, recent achievements in 3D visualization of biological samples from the Raman perspective, are explored including scanning mechanism, light sheet, tomography strategy, compressive sensing, holography, and tissue clearing. Importantly, these platforms are compatible with biomedical research, thus allowing the imaging of chemical constituents and the distribution of samples in a whole volume. As a unique volumetric imaging tool for biological discovery, these methods may provide a strategy to accelerate new discoveries across diverse fields of research.

Acute eosinophilic pneumonia presented with hemoptysis as the first manifestation

We reported a case of 38-year-old man who was admitted with a 10-day history of hemoptysis. He had reported a significant increasing in tobacco consumption in the week prior to admission. Chest computed tomographic (CT) scans showed multiple ground-glass opacities in bilateral lung fields. The percentage of eosinophils in the bronchoalveolar lavage fluid was over 25%. Based on the patient's imaging findings and the predominant eosinophilia in the bronchoalveolar lavage, a diagnosis of acute eosinophilic pneumonia was made. Systemic corticosteroid therapy was initiated. Repeated CT scan showed the opacities were completely resolved afterwards. Compared with the previous case reports published in Pubmed, which included 234 patients with AEP, the present case described hemoptysis as the only manifestation in an AEP patient, indicating the diversity of clinical manifestations of AEP. Clinicians should consider the probability of AEP in patients with hemoptysis and pulmonary ground-glass opacities after acute tobacco exposure if the disease cannot be explained by other causes.

Nasal and temporal intraconal orbital fat densities differ on computerized tomographic scans of normal orbits

AbstractBackground and AimThe anatomy and function of different areas within the intraconal fat remain poorly understood. A potential difference between nasal and temporal orbital fat densities in normal eyes may assist clinicians and radiologists in more accurately interpreting computerized tomographic (CT) scans and making more informed diagnostic and therapeutic decisions for patients with orbital pathologies.Patients and MethodsData from randomly selected patients who underwent orbital CT scans at Sheba Medical Center in 2022 were analyzed. Patients with abnormal imaging findings in either orbit were excluded. Intraconal orbital fat density was measured in six nasal and temporal sites by means of Hounsfield units (HU).ResultsThe study included 54 patients (mean age 45.3 ± 25.5 years, 29 [54%] females) who were scanned for ophthalmologic etiologies unrelated to the orbit. Non-contrast-enhanced (NCE)-CT scans were available for 36 patients (67%), CE-CT scans for 31 patients (57%), and both CE and NCE scans for 13 patients. HU values were significantly higher in the nasal orbit compared to the temporal orbit on both NCE-CT (−75.8 ± 7.5 nasal vs. −78.1 ± 8.4 temporal, P < 0.001) and CE-CT (−72.7 ± 6.7 nasal vs. −74.6 ± 8.6 temporal, P = 0.02). Age, sex, and laterality had no effect on the HU values.ConclusionsThe density of nasal intraconal fat is higher compared to temporal intraconal fat, as observed on both CE and NCE-CT scans of normal eyes.These results suggest the presence of anatomical differences between these compartments and could have significant clinical implications in the diagnosis of various orbital pathologies.

A Comparative Analysis of Individual Readers and an Autonomous Deep-Learning-Based Algorithm for Assessing Total Metabolic Tumor Volume from Positron Emission Tomography/Computed Tomography Scans

A Comparative Analysis of Individual Readers and an Autonomous Deep-Learning-Based Algorithm for Assessing Total Metabolic Tumor Volume from Positron Emission Tomography/Computed Tomography Scans

Concomitant Factors Associated With Tillaux-Chaput Fractures in Adults: A Case-Control Study.

Tillaux-Chaput fractures (TCFs) consist of fractures of the anterolateral distal tibia. They rarely occur in isolation in adults. When TCFs are missed, there is a risk of chronic pain, instability, and ankle osteoarthritis. This study aimed to identify which factors are related to the presence of TCFs in ankle injuries. A retrospective review of 1134 ankle fractures evaluated between 2013 and 2023 at a level 1 trauma center was performed. Inclusion criteria were patients aged ≥18 years, ankle radiographs and computed tomographic (CT) scan evaluation, and the presence of a TCF confirmed by CT scan. Exclusion criteria were prior ankle surgery, pilon, or distal tibial fractures. A musculoskeletal radiologist and a foot and ankle-trained orthopaedic surgeon classified the TCFs into type 1, an extraarticular avulsion; type 2, a fracture involving the incisura fibularis; and type 3, a fracture with impaction of the anterolateral tibial plafond. A matching control group of ankle fractures without TCF was created with a 1:2 ratio. The following variables were collected: sex, age (<50 vs >50 years), ankle dislocation or subluxation, Weber classification, Maisonneuve fracture, type of medial and posterior malleolar fracture, Lauge-Hansen classification, malleoli involved, and osteochondral lesion of the talus. Multivariate logistic regression was performed to detect which variables had an association with the TCF and their subtypes. P value <.05 was considered significant. A total of 481 ankle fractures had radiographs and CT scans available for evaluation, of which 83 (17.3%) had a TCF. Of these, 44.6% were type 1, 44.6% type 2, and 9.6% type 3. The mean age was 52.2 years; 66.3% were women. Six patients (7.2%) had an isolated TCF. Fifty-eight (69.9%), 50 (60.2%), and 62 (74.7%) ankles had involvement of the lateral, medial, and posterior malleolus, respectively. Age ≥50 years (OR 2.73, 95% CI 1.45-5.14) and pronation external rotation injuries (OR 2.94, 95% CI 1.43-6.06) had a significant association with TCF. Moreover, ankle dislocation or subluxation (OR 3.16, 95% CI 1.11-8.96) and the absence of posterior malleolar fracture (OR 5.97, 95% CI 1.65-21.6) were significantly associated with TCF type 2 and 3. In this study, age ≥50 years and pronation external rotation injuries were the unique independent risk factors for TCF. Furthermore, ankle dislocation or subluxation and the absence of posterior malleolar fractures increased the odds of having a more severe TCF. This study provides insights into the factors associated with TCF and its subtypes during adulthood.

A novel approach to calculate the required volume of air for bronchial blockers in young children.

Bronchial blocker balloons inflated with small volumes of air increase balloon pressure, involving a risk of airway injury especially in young children. However, there are no established guidelines regarding the appropriate volumes of air required to provide safe bronchial occlusion. This study aimed to introduce a novel method for calculating the amount of air required for safe bronchial blocker balloon occlusion for one lung anesthesia in young children. We included 79 pediatric patients who underwent video-assisted thoracoscopic surgery at our hospital. Preoperatively, the balloon pressure and corresponding diameter of 5F bronchial blockers inflated with different volumes of air were measured. Intraoperatively, bronchial diameters measured by computerized tomographic scans were matched to the exvivo measured balloon diameters. The quality of lung isolation, incidence of balloon repositioning, and airway injury were documented. Postoperatively, airway injury was evaluated through fiberoptic bronchoscopy. Balloon pressure and balloon diameter showed linear and nonlinear correlations with volume, respectively. The median lengths of the right and left mainstem bronchi were median (interquartile range) range: 5.3 mm (4.5-6.3) 2.7-8.15 and 21.8 (19.6-23.4) 14-29, respectively. Occluding the left mainstem bronchus required <1 mL of air, with a balloon pressure of 27 cm H2O. The isolation quality was high with no case of mucosal injury or displacement. Occluding the right mainstem bronchus required a median air volume of 1.3 mL, with a median balloon pressure of 44 cm H2O. One patient had poor lung isolation due to a tracheal bronchus and another developed mild and transient airway injury. The bronchial blocker cuff should be regarded as a high-pressure balloon. We introduced a new concept for safe bronchial blocker balloon occlusion for one-lung ventilation in small children.

Partial crystallization in Pd-BMG systems: From understanding structure towards influencing functionality through temperature-time series

Small quantities of crystalline domains created in an amorphous matrix are seen as an active driver for enhanced properties in bulk metallic glasses (BMGs). We investigated partial crystallization and phase transformations through a series of isotherms at 370°C performed on amorphous Pd-based BMG samples with the nominal composition of Pd43Cu27Ni10P20 (Pd-BMG) and a density of 9.425 g/cm3. X-ray based methods such as X-ray diffraction (XRD) and phase enhanced micro-computed tomography (μ-CT) have been pushed to their limits for studying atomic structure and morphology, while time available before crystallization has additionally been investigated via differential scanning calorimetry (DSC), and are combined with optical microscopy (OM), scanning electron microscopy (SEM), and hardness measurements for their mechanical properties. We reveal that Pd-based BMG samples isothermally treated at 370 °C start to crystallize after 20 min and still undergo phase transformations and recrystallization even after being fully crystalline after 60 min of the isothermal treatment. Interestingly, 3D phase enhanced micro-computed tomography shows a clear separation of two domains of slightly different densities. We highlight X-ray tomographic scans, allowing the 3D spatial visualization of extremely low-density contrast in different material domains, thus providing a multi-scale physical description of the Pd-BMG system. Interesting is the fact, that the re-crystallization is not homogenous and the crystalline domains can reach large size of (100–200 μm) in an amorphous matrix.

Velocity Scanning Tomography for Room-Temperature Quantum Simulation.

Quantum simulation offers an analog approach for exploring exotic quantum phenomena using controllable platforms, typically necessitating ultracold temperatures to maintain the quantum coherence. Superradiance lattices (SLs) have been harnessed to simulate coherent topological physics at room temperature, but the thermal motion of atoms remains a notable challenge in accurately measuring the physical quantities. To overcome this obstacle, we implement a velocity scanning tomography technique to discern the responses of atoms with different velocities, allowing cold-atom spectroscopic resolution within room-temperature SLs. By comparing absorption spectra with and without atoms moving at specific velocities, we can derive the Wannier-Stark ladders of the SL across various effective static electric fields, their strengths being proportional to the atomic velocities. We extract the Zak phase of the SL by monitoring the ladder frequency shift as a function of the atomic velocity, effectively demonstrating the topological winding of the energy bands. Our research signifies the feasibility of room-temperature quantum simulation and facilitates their applications in quantum information processing.

Discerning Transuranic Sub-Concealments in Nuclear Waste Barrels Using γ-Ray Spectrometry: A Non-Invasive Assay Strategy To Combat the Threat of Nuclear Diversion.

Insufficient inventory control arising from inadequate monitoring procedures can lead to vulnerabilities in nuclear security. In addition, insider threats, by either malicious intent or negligence, can pose a substantial risk by exploiting such deficiencies to perform unlawful actions, such as theft or diversion, which may lead to compromised nuclear security. Interim storage barrels, intended for temporary containment of low-density nuclear waste, require special attention in this regard. In certain scenarios, the inadequacy of the existing waste barrel assay methodologies to identify and correctly measure any undesirable transuranic subconcealment present inside may pose a risk of nuclear diversion. The present work aims to establish an absolute waste barrel assay procedure to mitigate such risks by offering a robust method for the detection and assay of transuranic subconcealments in nuclear waste barrels using high-resolution γ-ray spectrometry. Challenges related to the varying amounts of attenuation experienced by the γ-rays within the subconcealments, low-density matrix, and the steel barrel wall have been addressed by an iterative photopeak efficiency transfer approach. The methodology has been verified for the assay of seven mock-up samples mimicking nuclear diversion attempts using waste barrels, for which conventional barrel scanning would be inadequate and tomographic scanning would be highly time-consuming. Using this methodology, Pu and 241Am isotopes have been assayed within <10% of the expected value for the majority, with the measurement uncertainty of <10%. The present method, which is simple and noninvasive, can identify inconsistencies with the labeled inventory and detect potential diversion attempts.

Structural properties and mechanical behavior of three-dimensional cylindrical particle-like systems under in situ loading

To investigate the mechanical behavior of granular systems and their impact on density uniformity during compression, a three-dimensional micro-CT in situ loading experiment was conducted on a cylindrical granular system. The granular system was subjected to tomographic scanning and reconstruction, and the variation patterns of structural parameters such as volume fraction, porosity, and intrinsic density during the in situ loading process were analyzed. Internal pores within the granular system were extracted to obtain changes in pore area at each layer, allowing for an analysis of the evolving patterns of layered pore areas across different regions of the granular system during loading. This characterization elucidated the dynamic evolution process of compaction within the granular system. A contact network model for the granular system was established using particle contact area as a representation of inter-particle contact forces, revealing inherent connections between particle contact networks and macroscopic mechanical behaviors within the granular system.

Development of a nanometre scale X-ray speckle-based CT technique through the 3-D histological assessment of an acute respiratory distress syndrome model

The study of biological soft tissue structures at the micron scale details the function of healthy and pathological tissues, which is vital in the diagnosis and treatment of diseases. Speckle based X-ray phase contrast tomographic scans at a nanometer scale have the potential to thoroughly analyse such tissues in a quantitative and qualitative manner. Diamond light source, the UKs national synchrotron facility developed and refined a 1-D X-ray speckle-based imaging technique, referred to as Fly scan mode. This novel image acquisition technique was used to perform a rapid structural composition scan of rodent lung histology samples. The rodent samples were taken from healthy and Staphylococcus aureus induced acute respiratory distress syndrome models. The analysis and cross comparison of the fly scan method, absorption-based tomography and conventional histopathology H&E staining microscopy are discussed in this paper. This analysis and cross comparison outline the ways the speckle-based technique can be of benefit. These advantages include improved soft tissue contrast, 3-D volumetric rendering, segmentation of specific gross tissue structures, quantitative analysis of gross tissue volume. A further advantage is the analysis of cellular distribution throughout the volumetric rendering of the tissue sample. The study also details the current limitations of this technique and points to ways in which future work on this imaging modality may progress.

Cone-Beam Computed Tomographic Scan–based Assessment of the Correlation between the Location of Caries and Pulp Canal Obliteration: An Aid to Treatment Planning

IntroductionThis study aimed to determine the correlation between proximal caries and the extent and site of pulp canal obliteration (PCO) in cone-beam computed tomographic (CBCT) scans of mandibular molar teeth. MethodsA total of 1491 CBCT scans of patients 18–49 years of age were selected from the database (2002–2022). From them, 328 teeth with proximal caries and satisfying inclusion criteria were evaluated by 2 calibrated evaluators. PCO was observed in the sagittal and coronal planes. PCO and proximal caries were compared concerning different age groups, sexes, and sites using an independent sample t test. ResultsThe prevalence of PCO among patients with proximal caries is 47%. In mesial proximal caries, the extent of PCO is significantly greater in the distal root canal (73.4%), whereas in distal proximal caries, PCO is more often found in the mesial canal (77.3%). The mean extent of intraradicular calcification was higher in the distal canal (P < .001). Moreover, mesial proximal caries showed a greater extent of intraradicular obliteration (P < .001). The probability of developing PCO was significantly higher in females (P = .003). ConclusionsWithin the limitations of this study, it can be concluded that the extent of calcification is more common on the opposite side of the location of the proximal caries. Moreover, such intraradicular calcification is greater in a distal canal compared to a mesial canal. Sex plays a significant role in the calcification process, showing higher predilection in females compared to males.

Change in Talar Axial Rotation and Pain Intensity Following Correction of Progressive Collapsing Foot Deformity.

The talus is more internally rotated within the ankle mortise in progressive collapsing foot deformity (PCFD) patients. However, no studies have investigated the change in talar axial rotation (AR) in PCFD postoperatively. The primary aim was to investigate the change in talar AR following PCFD reconstruction. Secondary aims were to determine whether talar AR changes were associated with other radiographic measurements or specific procedures, and whether postoperative talar AR was associated with 2-year patient-reported outcome scores. Twenty-seven patients older than 18 years who underwent flexible PCFD reconstruction with preoperative and at least 5-month postoperative weightbearing computed tomographic (WBCT) scans and radiographs and had preoperative and at least 2-year postoperative PROMIS scores were included. Patients with talonavicular fusions were excluded. Talar AR was the angle between the transmalleolar axis and talar axis on WBCT scans, with smaller angles representing more internal rotation as described by Kim et al. Hindfoot moment arm, Meary angle, fibulocalcaneal and talocalcaneal distance, subtalar middle facet uncoverage, and talonavicular angle were measured on radiographs. Postoperative talar AR was 49.7 degrees (IQR, 45.9, 57.3), which was more externally rotated than preoperative AR by a median of 8.3 degrees (IQR, 2.2, 15.7) (P > .001). The change in talar AR was not associated with changes in any radiographic parameter. Increasing external talar AR was associated with an increase in postoperative PROMIS pain intensity (rs = 0.38, 95% CI 0.00, 0.67). Lateral column lengthening and subtalar fusion procedures were not associated with changes in talar AR (P > .10). PCFD reconstruction results in external rotation of the talus within the ankle mortise. Kim et al found that control patients had approximately 40 to 60 degrees of talar AR, which is similar to this study's corrected position of the talus. However, increasing talar external rotation resulted in worse postoperative PROMIS pain intensity, suggesting the possibility of overcorrecting the internal AR deformity.

Thrombectomy for Stroke With Large Infarct on Noncontrast CT

Recent large infarct thrombectomy trials used heterogeneous imaging modalities and time windows for patient selection. Noncontrast computed tomographic (CT) scan is the most common stroke imaging approach. It remains uncertain whether thrombectomy is effective for patients with large infarcts identified using noncontrast CT alone within 24 hours of stroke onset. To evaluate the effect of thrombectomy in patients with a large infarct on a noncontrast CT scan within 24 hours of onset. Open-label, blinded-end point, bayesian-adaptive randomized trial with interim analyses for early stopping (futility or success) or population enrichment, which was conducted at 47 US academic and community-based stroke thrombectomy centers. Three hundred patients presenting within 24 hours with anterior-circulation, large-vessel occlusion and large infarct on noncontrast CT scan, with Alberta Stroke Program Early CT Scores of 2 to 5, were randomized to undergo thrombectomy or usual care. Enrollment occurred July 16, 2019 to October 17, 2022; final follow-up, January 25, 2023. The intervention patients (n = 152) underwent endovascular treatment using standard thrombectomy devices and usual medical care. Control patients (n = 148) underwent usual medical care alone. The primary efficacy end point was improvement in 90-day functional outcome measured using mean utility-weighted modified Rankin Scale (UW-mRS) scores (range, 0 [death or severe disability] to 10 [no symptoms]; minimum clinically important difference, 0.3). A bayesian model determined the posterior probability that the intervention would be superior to usual care; statistical significance was a 1-sided posterior probability of .975 or more. The primary adverse event end point was 90-day mortality; secondary adverse event end points included symptomatic intracranial hemorrhage and radiographic intracranial hemorrhage. The trial enrolled 300 patients (152 intervention, 148 control; 138 females [46%]; median age, 67 years), without early stopping or enrichment; 297 patients completed the 90-day follow-up. The mean (SD) 90-day UW-mRS score was 2.93 (3.39) for the intervention group vs 2.27 (2.98) for the control group with an adjusted difference of 0.63 (95% credible interval [CrI], -0.09 to 1.34; posterior probability for superiority of thrombectomy, .96). The 90-day mortality was similar between groups: 35.3% (53 of 150) for the intervention group vs 33.3% (49 of 147) for the control group. Six of 151 patients (4.0%) in the intervention group and 2 of 149 (1.3%) in the control group experienced 24-hour symptomatic intracranial hemorrhage. Fourteen patients of 148 (9.5%) in the intervention group vs 4 of 146 (2.7%) in the control group experienced parenchymal hematoma type 1 hemorrhages; 14 (9.5%) in the intervention group vs 5 (3.4%) in the control group experienced parenchymal hematoma type 2 hemorrhages; and 24 (16.2%) in the intervention group vs 9 (6.2%) in the control group experienced subarachnoid hemorrhages. Among patients with a large infarct on noncontrast CT within 24 hours, thrombectomy did not demonstrate improvement in functional outcomes. But the width of the credible interval around the effect estimate includes the possibility of both no important effect and a clinically relevant benefit, so the potential role of thrombectomy with this imaging approach and time window will likely require additional study. ClinicalTrials.gov Identifier: NCT03805308.

Intracerebral hemorrhage risk after adjunct intraarterial thrombolysis in thrombectomy-treated acute ischemic stroke.

Intraarterial thrombolysis as an adjunct to mechanical thrombectomy is increasingly being considered to enhance reperfusion in acute ischemic stroke patients. Intraarterial thrombolysis may increase the risk of post-thrombectomy intracerebral hemorrhage (ICH) in certain patient subgroups. We analyzed acute ischemic stroke patients treated with mechanical thrombectomy in a multicenter registry. The occurrence of any (asymptomatic and symptomatic) post-thrombectomy ICH was ascertained using standard definition requiring serial neurological examinations and computed tomographic scans acquired within 48hours of the thrombectomy. We determined the risk of ICH in subgroups defined by clinical characteristics and the use of intravenous (IV) thrombolysis. A total of 146 (7.5%) patients received intraarterial thrombolysis among 1953 acute ischemic stroke patients who underwent mechanical thrombectomy. The proportion of patients who developed any ICH was 26 (17.8%) and 510 (28.2%) among patients who were and were not treated with intraarterial thrombolysis, respectively (p=.006). The proportion of patients who developed symptomatic ICH was 4 (2.7%) and 30 (1.7%) among patients who were and were not treated with intraarterial thrombolysis, respectively (p=.34). Among patients who received IV thrombolysis (n=1042), the proportion of patients who developed any ICH was 9 (16.7%) and 294 (30.7%) among patients who were and were not treated with intraarterial thrombolysis, respectively (p=.028). The risk was not different in strata defined by age, gender, location of occlusion, preprocedure National Institutes of Health Stroke Scale score, time interval between symptom onset and thrombectomy, Alberta Stroke Program Early CT Score, systolic blood pressure, and serum glucose concentrations. In patients undergoing mechanical thrombectomy, the risk of any ICH and symptomatic ICH was not increased with intraarterial thrombolysis, including in those who had already received IV thrombolytics.