CT Technology Research Articles

Automated Segmentation and Measurements of Pulmonary Cysts in Lymphangioleiomyomatosis across Multiple CT Scanner Platforms over a Period of Two Decades.

(1) Background: Lymphangioleiomyomatosis is a genetic disease that affects mostly women of childbearing age. In the lungs, it manifests as the progressive formation of air-filled cysts and is associated with a decline in lung function. With a median survival of 29 years after the onset of symptoms, computed-tomographic monitoring of cystic changes in the lungs is a key part of the management of the disease. However, the current standard method to measure cyst burdens from CT is semi-automatic and requires manual adjustments from trained operators to obtain consistent results due to variabilities in CT technology and imaging conditions over the long course of the disease. This can be impractical for longitudinal studies involving large numbers of scans and is susceptible to subjective biases. (2) Methods: We developed an automated method of pulmonary cyst segmentation for chest CT images incorporating novel graphics processing algorithms. We assessed its performance against the gold-standard semi-automated method performed by experienced operators who were blinded to the results of the automated method. (3) Results: the automated method had the same consistency over time as the gold-standard method, but its cyst scores were more strongly correlated with concurrent pulmonary function results from the physiology laboratory than those of the gold-standard method. (4) Conclusions: The automated cyst segmentation is a competent replacement for the gold-standard semi-automated process. It is a solution for saving time and labor in clinical studies of lymphangioleiomyomatosis that may involve large numbers of chest CT scans from diverse scanner platforms and protocols.

Damage identification and failure morphological reconstruction for engineering rock mass

By and large, the traditional CT technology cannot involve the important problems of intrinsic damage identification and reconstruction of large-scale engineering rock mass. In the light of the numerical simulation technology, the digital image processing technology and the three-dimensional reconstruction technology, a kind of numerical computed tomography method is proposed. On the basis of numerical simulation, the external program of the characteristic variable of rock mass damage and failure is called to generate the cloud map model of rock mass damage and failure. In addition, the sequence layered profile images are created by automatically cutting the cloud map model via the self-complied program, as well as adopting the digital image processing technology for batch cropping, batch gray-scale and binarization processing. Eventually, the three-dimensional reconstruction technology is employed to reconstruct the spatial distribution morphology of the internal damage and failure of rock mass. At that point, the proposed method is applied to apparently exhibit the evolution morphology of spatial distribution of the Rm 417 tunnel failure area, and effectively reveal the intrinsic connection of the Rm 417 tunnel failure, such as the location, evolution path and morphology. Consequently, the validity and reliability of the numerical computed tomography method are verified, which has satisfactory applicability and applied values.

Microscopic mechanisms and chloride resistance performance of silane coupling agent self-assembly on reinforced concrete utilizing X-ray CT technology: A comprehensive investigation

To enhance corrosion resistance in reinforced concrete exposed to chloride environments, a γ-aminopropyltriethoxysilane (KH550) solution was used to treat the steel bar surface. This study investigated the corrosion resistance and microscopic mechanism of self-assembled silane film-modified steel bars. Surface morphology, elemental composition, and functional group changes were analyzed using SEM, EDS, and FTIR before and after solution treatment to determine the optimal treatment concentration. X-ray computed tomography (X-ray CT) was employed to analyze rust evolution and fracture characteristics in steel bars treated with silane coupling agent self-assembly technology. Results revealed that the self-assembly of molecules significantly enhanced corrosion resistance when using a water to ethanol to KH550 solution volume ratio of 50:3:10. The corrosion resistance mechanism of silane self-assembled steel bars against chloride salt corrosion was verified through X-ray CT technology, quantifying the volume expansion rate of rust products.

Three-Dimensional Reconstruction and Seepage Simulation of Vermiculite Materials Based on CT Technology

The purpose of this paper is to investigate the 3D reconstruction and seepage simulation of vermiculite-based sealing materials in order to clarify the relationship between material structure and fluid leakage in order to improve their performance and reliability and to provide a foundation for accurate leakage rate calculation under various conditions. CT scanning and 3D reconstruction techniques were used to examine the pore structure and fractal properties of vermiculite-based sealing materials. The seepage mechanism under compression was examined using a porous medium model. The findings demonstrate that the vermiculite-based sealing materials have self-similarity and scale-invariant fractal properties. The porous media model in compression exhibits a low leakage rate, opening up a new avenue for realizing microscopic leakage studies with a leakage rate of 1 × 109 in compression.

The Accuracy of CT Scanning in the Assessment of the Internal and External Qualitative Features of Wood Logs.

The qualitative evaluation of harvested raw logs and sawlogs is mainly based on the quantitative and qualitative evaluation of the visible macroscopic features of the wood. Modern methods allow for the analysis of whole logs by means of computed tomography. These devices can analyze the internal qualitative features of wood that are not visible on the external structures of the logs. The aim of this work was to evaluate the detection accuracy of a CT-scanning device intended for scanning logs on the internal qualitative features of wood using model trunks. Two logs of beech and oak with a length of 4 m were selected for the analysis, based on availability. Qualitative features were identified through computed tomography scanning, visually identified on cut sections, and then manually measured in accordance with applicable legislation. Relatively good agreement was demonstrated for the detected features in terms of identifying their location (dimension in millimeters from the end of the log). For this parameter, the average differences were 0.90% on the beech log and only 1.21% on the oak log. Relatively high accuracy was shown via CT detection of qualitative features in the beech section (with average differences in dimensions of only 3.5%). In the case of the oak log, the dimensions of the quality features were significantly overestimated. These results indicate that CT scanning technology may have a problem with some hardwood species. It was primarily developed for coniferous tree species, and software algorithms are, therefore, not yet fully adapted to the precise detection of the dimensions of individual quality features. Despite the detected differences, it was confirmed that the CT technology of scanning harvested wood can have a fundamental impact on optimization procedures in the recovery and processing of wood. Renting a scanning line for a certain capacity of wood volume appears to be a deployment option for forestry operations and smaller wood processing operations. Thus, this technology can become an important factor in improving the economic evaluation of the final production of wood.

Bidirectional Mendelian randomization analysis of the genetic association between primary lung cancer and colorectal cancer

BackgroundWith the development and popularization of low-dose chest CT technology, the diagnosis and survival rates of patients with early lung cancer (LC) have significantly improved. The occurrence of colorectal cancer (CRC) as the second primary cancer (SPC) in primary lung cancer (PLC) survivors has become an essential factor affecting the prognosis of early LC. This study explored the potential association between PLC and CRC genetically, laying a foundation for developing SPC-CRC prevention strategies after primary early LC.MethodsBased on a two-sample bidirectional Mendelian randomization (MR) design, this study systematically screened genetic instrumental variables (IVs) based on the genome-wide association studies (GWAS) of PLC and CRC, applied inverse variance weighted (IVW) as the main method to assess the incidence association between the two cancers, and used a variety of other MR methods for supplementary analysis. Finally, the Genetic Risk Scores (GRS) method was used for secondary analysis to verify the results robustness further.ResultsFrom LC to CRC forward MR analysis, 20 genetic IVs of overall LC, 15 genetic IVs of squamous cell lung carcinoma (LUSC), and 10 genetic IVs of adenocarcinoma of the lung (LUAD) were screened. In the reverse MR analysis from CRC to LC, 47 genetic IVs for overall CRC, 37 for colon cancer, and 25 for rectal cancer were screened. The IVW method and a variety of MR methods all found that overall LC and CRC were significantly associated at the genetic level. Subgroup analysis also showed that LUSC was associated with CRC. And the results of the GRS method were consistent with those of the main analysis, confirming the robustness of the study.SummaryOur MR study found an association between LC and CRC, with an increased risk of SPC-CRC following PLC, especially LUSC. Our study provides an essential basis for the precise prevention of SPC-CRC after PLC, suggesting that we should pay more attention to the population with a history of PLC in clinical work, and pay close attention to the incidence of SPC-CRC, and carry out intervention and treatment as soon as possible.

Subtalar Distraction Bone Block Arthrodesis for Calcaneus Fracture Malunion

Intra-articular calcaneus fractures are associated with a high rate of malunion resulting in hindfoot and ankle impingement, peroneal tendinitis, sural neuritis, arthritis, hindfoot varus or valgus deformity, loss of hindfoot height, and resulting gastrocnemius-soleus complex weakness and gait dysfunction. These issues can arise whether the patient’s injury is treated conservatively with non–weight-bearing precautions, neglected/missed, or treated surgically with open reduction and internal fixation. The sequelae of calcaneal malunions can arise early or late in this process. For patients undergoing subtalar arthrodesis following calcaneus fracture malunion, the use of a bone block wedge can assist with achieving a stable ,well-aligned, pain-free hindfoot. Patient selection, preoperative planning, careful surgical technique, and compliance with postoperative care pathways are critical to optimize patient outcomes and healing of this complex reconstruction. Recent evidence supports the utility of weight-bearing CT to assist with preoperative planning for subtalar arthrodesis. Wedges used in subtalar distraction arthrodesis include bulk autograft (tricortical iliac crest), allograft (pre-fashioned or intraoperatively fashioned wedges from femoral head allograft or other source), and metallic wedges. These wedges are typically secured with screws spanning and compressing the arthrodesis site, which is filled with a mixture of concentrated bone marrow aspirate, bone growth factors, and allograft bone. Concomitant procedures may be indicated to ensure the overall success of the procedure, such as extra-articular, calcaneal osteotomy for additional realignment purposes and/or arthrolysis. A review of the literature shows high rates of union following subtalar bone block arthrodesis with improved functional outcomes. Our preferred technique for a bone block distraction subtalar arthrodesis, described herein, includes the use of an allograft wedge. Ongoing advances, such as the development of novel materials and structures for use in subtalar bone block arthrodesis, but most importantly, the incorporation of weight-bearing CT technology and potential for preoperative CT navigation to make this procedure more predictable, are all important areas for further exploration and future research. Level of Evidence: Level—4.

Catalytic gasification of large particle-size biomass with loaded AAEMs under oxygen-steam atmosphere

To evaluate the effect of alkali and alkaline earth metals (AAEMs) species on the catalytic gasification of large particle-size biomass, a vertical fixed-bed reactor is conducted for candlenut wood gasification under the oxygen-stream atmosphere. The biochar samples derived from gasification are characterized by SEM, X-ray CT, BET, and FTIR. Tar and syngas are analyzed via GC–MS and GC respectively. Advanced X-ray CT technology provides beneficial visualization to assist in the interpretation of the catalytic gasification of large particle-size biomass loaded with AAEMs. The results indicate that a progressive augmentation of AAEMs content along the radial direction and end surface for all loaded samples and biochar samples, which could also be visualized from the 3D reconstruction of X-ray CT. Many large pores (40–60 μm) aligned along the grain direction collapse after the gasification and generate numerous micropores in biochar samples. 10–20 μm pores are more prominent in biochar as the biomass samples are loaded with KCl and CaCl2. The biochar from gasification of biomass loaded with CaCl2 has more well-developed pores, a larger specific surface area, and –OH compounds, aldehydes, ketones and carboxylic acids. The addition of AAEMs facilitates the high generation of M1 compounds (contains 1 benzene ring) in the tar and suppresses the enhancement of M4 compounds, long-chain alkanes, and other compounds. The lowest carbon conversion (57.12 %) is acquired from acid-washed sample. H2 concentration augments but CO concentration declines by loading AAEMs. The highest H2 concentration of 62.1 % is detected by the addition of CaCl2. When loaded with KCl, the syngas calorific value reduces by 1.37 %, whereas loaded with NaCl, CaCl2, and MgCl2 show an augmentation of 11.48 %, 10.56 %, and 2.55 %, respectively. A decrement of CnHx concentration in the syngas derived from gasification of biomass samples loaded with KCl and MgCl2 and an increment one loaded with NaCl and CaCl2 are acquired.

Milestones in CT: Past, Present, and Future.

In 1971, the first patient CT examination by Ambrose and Hounsfield paved the way for not only volumetric imaging of the brain but of the entire body. From the initial 5-minute scan for a 180° rotation to today's 0.24-second scan for a 360° rotation, CT technology continues to reinvent itself. This article describes key historical milestones in CT technology from the earliest days of CT to the present, with a look toward the future of this essential imaging modality. After a review of the beginnings of CT and its early adoption, the technical steps taken to decrease scan times-both per image and per examination-are reviewed. Novel geometries such as electron-beam CT and dual-source CT have also been developed in the quest for ever-faster scans and better in-plane temporal resolution. The focus of the past 2 decades on radiation dose optimization and management led to changes in how exposure parameters such as tube current and tube potential are prescribed such that today, examinations are more customized to the specific patient and diagnostic task than ever before. In the mid-2000s, CT expanded its reach from gray-scale to color with the clinical introduction of dual-energy CT. Today's most recent technical innovation-photon-counting CT-offers greater capabilities in multienergy CT as well as spatial resolution as good as 125 μm. Finally, artificial intelligence is poised to impact both the creation and processing of CT images, as well as automating many tasks to provide greater accuracy and reproducibility in quantitative applications.

Transformer With Double Enhancement for Low-Dose CT Denoising.

Increasingly serious health problems have made the usage of computed tomography surge. Therefore, algorithms for processing CT images are becoming more and more abundant. These algorithms can lessen the harm of cumulative radiation in CT technology for the patient while eliminating the noise of image caused by dose reduction. However, the mainstream CNN-based algorithms are inefficient when dealing with features in broad regions. Inspired by the large receptive field of transformer framework, this paper designs an end-to-end low-dose CT (LDCT) denoising network based on the transformer. The overall framework of network contains a main branch and dual side branches. Specifically, the overlapping-free window-based self-attention transformer block is adopted on the main branch to realize image denoising. On the dual side branches, we propose double enhancement module to enrich edge, texture, and context information of LDCT images. Meanwhile, the receptive field of network is further enlarged after processing, which is helpful for building model's long-range dependencies. The outputs of the side branches are concatenated to the middle layer of the network for enhancing information and generating high-quality CT images. In addition, to better train the network and achieve the expected results, we introduce a compound loss function including mean squared error (MSE), multi-scale perceptual (MSP), and Sobel-L1 (SL) to make the denoised image closer to the targeted norm-dose CT (NDCT) image. Lastly, we conducted experiments on two clinical datasets including abdomen, head, and chest LDCT images with 25%, 25%, and 10% of the full dose, respectively. The experimental results demonstrated that the proposed DEformer achieved better denoising performance than the existing algorithms.

Evaluation of Image Quality for High Heart Rates for Coronary Computed Tomographic Angiography with Advancement in CT Technology: The CONVERGE Registry.

This study aims to evaluate image quality in patients with heart rates above or equal to 70 beats per minute (bpm), performed on a 16 cm scanner (256-slice General Electric Revolution) in comparison to a CT scanner with only 4 cm of coverage (64 slice Volume CT). Recent advancements in image acquisition, such as whole-heart coverage in a single rotation and post-processing methods in coronary computed tomographic angiography (CCTA), include motion-correction algorithms, such as SnapShot Freeze (SSF), which improve temporal resolution and allow for the assessment of coronary artery disease (CAD) with lower motion scores and better image qualities. Studies from the comprehensive evaluation of high temporal- and spatial-resolution cardiac CT using a wide coverage system (CONVERGE) registry (a multicenter registry at four centers) have shown the 16 cm CT scanner having a better image quality in comparison to the 4 cm scanner. However, these studies failed to include patients with undesirable or high heart rates due to well-documented poor image acquisition on prior generations of CCTA scanners. A prospective, observational, multicenter cohort study comparing image quality, quantitively and qualitatively, on scans performed on a 16 cm CCTA in comparison to a cohort of images captured on a 4 cm CCTA at four centers. Participants were recruited based on broad inclusion criteria, and each patient in the 16 cm CCTA arm of the study received a CCTA scan using a 256-slice, whole-heart, single-beat scanner. These patients were then matched by age, gender, and heart rate to patients who underwent CCTA scans on a 4 cm CT scanner. Image quality was graded based on the signal-to-noise ratio, contrast-to-noise ratio, and on a Likert scale of 0-4: 0, very poor-4, excellent. 104 patients were evaluated for this study. The mean heart rate was 75 ± 7 in the 4 cm scanner and 75 ± 7 in the 16 cm one (p = 0.426). The signal-to-noise and contrast-to-noise ratios were higher in the 16 cm scanner (p = 0.0001). In addition, more scans were evaluated as having an excellent quality on the 16 cm scanner than on the 4 cm scanner (p < 0.0001) based on a 4-point Likert scale. The 16 cm scanner has a superior image quality for fast heart rates compared to the 4 cm scanner. This study shows that there is a significantly higher frequency of excellent and good studies showing better contrast-to-noise and signal-to-noise ratios with the 16 cm scanner compared to the 4 cm scanner.

Mid-term effectiveness of hip preservation in the reconstruction of ultrashort bone segments in the proximal femur with three-dimensional printed customized cementless intercalary endoprosthesis with an intra-neck curved stem

To explore the design points of a three-dimensional (3D) printed customized cementless intercalary endoprosthesis with an intra-neck curved stem and to evaluate the key points and mid-term effectiveness of its application in the reconstruction of ultrashort bone segments in the proximal femur. Between October 2015 and January 2021, 17 patients underwent reconstruction with a 3D printed-customized cementless intercalary endoprosthesis with an intra-neck curved stem. There were 11 males and 6 females, the age ranged from 10 to 76 years, with an average of 30.1 years. There were 9 cases of osteosarcoma, 4 cases of Ewing sarcoma, 2 cases of chondrosarcoma, 1 case of liposarcoma, and 1 case of myofibroblastoma. The disease duration was 5-14 months, with an average of 9.5 months. Enneking staging included 16 cases of stage ⅡB and 1 case of stage ⅢB. The distances from the center of the femoral head to the body midline and the acetabular apex were measured preoperatively on X-ray images. Additionally, the distances from the tip of the intra-neck curved stem to the body midline and the acetabular apex were measured at immediate postoperatively and last follow-up. The neck-shaft angle was also measured preoperatively, at immediate postoperatively, and at last follow-up. The status of osseointegration at the bone-prosthesis interface and bone growth into the prosthesis surface were assessed by X-ray films, CT, and Tomosynthesis-Shimadzu metal artefact reduction technology (T-SMART). The survival status of the patients, presence of local recurrence or distant metastasis, and occurrence of postoperative complications were assessed. The recovery of lower limb function was evaluated pre- and post-operatively using the Musculoskeletal Tumor Society (MSTS) scoring system, and pain relief was evaluated using the visual analogue scale (VAS) scores. The patient's femoral resection length was (163.1±57.5) mm, the remaining proximal femoral length was (69.6±9.3) mm, and the percentage of femoral resection length/total femoral length was 38.7%±14.6%. All 17 patients were followed up 25-86 months with an average of 58.1 months. During the follow-up, 1 patient died of lung metastasis at 46 months postoperatively, and the remaining 16 patients survived tumor-free. There was no complication such as periprosthetic infection, delayed incision healing, aseptic loosening, prosthesis fracture, or periprosthetic fracture. No evidence of micromotion or wear around the implanted stem of the prosthesis was detected in X-ray and T-SMART evaluations. There was no significant radiolucent lines, and radiographic evidence of bone ingrowth into the bone-prosthesis interface was observed in all stems. There was no significant difference in the distance from the tip of the curved stem to the body midline and the apex of the acetabulum at immediate postoperatively and last follow-up compared with the distance from the center of the femoral head to the body midline and the apex of the acetabulum before operation, respectively (P>0.05), and there was no significant difference in the above indexes between immediate postoperatively and last follow-up (P>0.05). The differences in the neck-shaft angle at various time points before and after operation were also not significant (P>0.05). At last follow-up, the MSTS score was 26.1±1.2 and the VAS score was 0.1±0.5, which were significantly improved when compared with those before operation [19.4±2.1 and 5.7±1.0, respectively] (t=14.735, P<0.001; t=21.301, P<0.001). At last follow-up, none of the patients walked with the aid of crutches or other walkers. The 3D printed customized cementless intercalary endoprosthesis with an intra-neck curved stem is an effective method for reconstructing ultrashort bone segments in the proximal femur following malignant tumor resection. The operation is reliable, the postoperative lower limb function is satisfactory, and the incidence of complications is low.

Musculoskeletal CT Imaging: State-of-the-Art Advancements and Future Directions.

CT is one of the most widely used modalities for musculoskeletal imaging. Recent advancements in the field include the introduction of four-dimensional CT, which captures a CT image during motion; cone-beam CT, which uses flat-panel detectors to capture the lower extremities in weight-bearing mode; and dual-energy CT, which operates at two different x-ray potentials to improve the contrast resolution to facilitate the assessment of tissue material compositions such as tophaceous gout deposits and bone marrow edema. Most recently, photon-counting CT (PCCT) has been introduced. PCCT is a technique that uses photon-counting detectors to produce an image with higher spatial and contrast resolution than conventional multidetector CT systems. In addition, postprocessing techniques such as three-dimensional printing and cinematic rendering have used CT data to improve the generation of both physical and digital anatomic models. Last, advancements in the application of artificial intelligence to CT imaging have enabled the automatic evaluation of musculoskeletal pathologies. In this review, the authors discuss the current state of the above CT technologies, their respective advantages and disadvantages, and their projected future directions for various musculoskeletal applications.

Dual-energy index variation when evaluating the potential ferromagnetism of ex vivo bullets.

An MRI is potentially hazardous for patients with retained ferromagnetic bullets. Recent studies have aimed to develop dual-energy computed tomography (DECT) as a screening tool for recognising highly ferromagnetic bullets. Inconsistent findings have been ascribed to inherent CT technology differences. Previous research demonstrated significant Hounsfield unit (HU) measurement variation among single-source CT machines. This study investigated the theoretical dual-energy index (DEI) variation between DECT machines when evaluating the potential ferromagnetic properties within the same sample of ex vivo bullets and metal phantoms. An experimental ex vivo study was conducted on eight metal phantoms and 10 unused bullets individually positioned in the same Perspex head phantom and scanned on two DECT machines. Two senior radiology registrars independently recorded the HU readings, and DEI values were calculated. Statistical analysis was performed using non-parametric methods for paired data, namely the Signed Rank Test. The DEI values based on mean HU readings between the DECT machines were compared. Inter- and intra-reader agreement was not statistically significant. The metal phantoms had poor interscanner agreement, with an overlap of the ferromagnetic and non-ferromagnetic ranges. The bullets had good interscanner agreement, with a similar ferromagnetic to non-ferromagnetic relationship. The use of DEI values negates the previous assumption that significant interscanner variability exists among different DECT technologies while assessing highly attenuative ex vivo bullets. This investigation demonstrated that even though HU readings may be variable, the implementation of the DEI equation translates this into comparable values with good interscanner agreement.

Can We Miniaturize CT Technology for a Successful Mobile Stroke Unit Roll-Out?

Mortality from stroke remains high in Australia, especially for patients located outside the metropolitan cities. This is because they have limited access to specialized stroke facilities for optimal stroke treatment. Mobile stroke units have the capability to take CT scanners out to the patient however current CT commercial scanner designs are large and heavy. As such, this paper aims to design and develop a lightweight CT scanner for use in a mobile stroke unit (either road-based or air-based ambulance) to bring healthcare solution to patients in the rural and remote areas. We used the engineering design optimization approach to redesign and reduce the weight of the existing CT scanner with without compromised it structural performance. We managed to reduce the weight the CT scanner by three-fold while reducing design costs by allowing numerous simulations to be performed using computer software to achieve our design goals. The results are not only useful to optimize CT scanner structure to retrofit on a mobile stroke unit, but also bring the medical device solution to the market and support scalable solution to the larger community. Such an advance will allow for improved equity in healthcare whereby patients can be treated irrespective of location.

Bilateral extended FDK: An improved weighting method for static CT imaging.

Improving imaging speed has always been the focus of research in CT technology, which is related to the radiation dose and imaging quality of moving organs, including heart and blood vessels. However, it is difficult to achieve further improvement by increasing the rotation speed of the gantry due to its structural strength limitation. Differing from the conventional CTs, the static CT employs dozens of ray sources to acquire projection data from different angular ranges, and each source only needs to be rotated in a small range to finish a full 360° scan, thus greatly increasing the scanningspeed. As sources of static CT need to be evenly distributed over 360°, the sources and detectors have to be arranged on two parallel rings independently. Such a geometry can be considered as a special case of CT systems with a significantly large cone angle, that is, a part of the detector is missing in the vicinity of the mid-plane. Due to restriction of upper and lower bounds of the cone angle of the static CT, there are uneven projection data varying in each portion of the reconstruction volume, the conventional analytical or iterative reconstruction methods may introduce artifacts in the reconstructedoutcomes. Following the weighting approach extended FDK (xFDK) by Grimmer etal., we propose an improved bilateral xFDK algorithm (bixFDK), which focuses on the reconstruction of the expanded volume. With the same philosophy as xFDK in terms of weighting function design, bixFDK takes the longitudinal offset of the detector with respect to the source into consideration, making our method applicable to a wide range of CT geometries, especially for the static CT. Based on the proposed bixFDK, a new iterative scheme bixFDK-IR is also constructed to extend the applications to a wide range of scan protocols such as sparse-viewscan. The proposed method has been validated with the simulated phantom data and the actual clinical data of the static CT, and demonstrates that it can ensure good image quality and enlarge the reconstruction volume in z-direction of the staticCT. The bixFDK algorithm is an ideal reconstruction approach for static CT geometry, and the iterative scheme of bixFDK-IR is applicable to a wide range of CT geometries and scan protocols, thus providing a wide range of applicationscenarios.

The New Ice Age of Musculoskeletal Intervention: Role of Percutaneous Cryoablation in Bone and Soft Tissue Tumors.

In the rapidly evolving field of interventional oncology, minimally invasive methods, including CT-guided cryoablation, play an increasingly important role in tumor treatment, notably in bone and soft tissue cancers. Cryoablation works using compressed gas-filled probes to freeze tumor cells to temperatures below -20 °C, exploiting the Joule-Thompson effect. This cooling causes cell destruction by forming intracellular ice crystals and disrupting blood flow through endothelial cell damage, leading to local ischemia and devascularization. Coupling this with CT technology enables precise tumor targeting, preserving healthy surrounding tissues and decreasing postoperative complications. This review reports the most important literature on CT-guided cryoablation's application in musculoskeletal oncology, including sarcoma, bone metastases, and bone and soft tissue benign primary tumors, reporting on the success rate, recurrence rate, complications, and technical aspects to maximize success for cryoablation in the musculoskeletal system.

A coarse-to-fine multi-scale feature hybrid low-dose CT denoising network

With the growing development and wide clinical application of CT technology, the potential radiation damage to patients has sparked public concern. However, reducing the radiation dose may cause large amounts of noise and artifacts in the reconstructed images, which may affect the accuracy of the clinical diagnosis. Therefore, improving the quality of low-dose CT scans has become a popular research topic. Generative adversarial networks (GAN) have provided new research ideas for low-dose CT (LDCT) denoising. However, utilizing only image decomposition or adding new functional subnetworks cannot effectively fuse the same type of features with different scales (or different types of features). Thus, most current GAN-based denoising networks often suffer from low feature utilization and increased network complexity. To address these problems, we propose a coarse-to-fine multiscale feature hybrid low-dose CT denoising network (CMFHGAN). The generator consists of a global denoising module, local texture feature enhancement module, and self-calibration feature fusion module. The three modules complement each other and guarantee overall denoising performance. In addition, to further improve the denoising performance, we propose a multi-resolution inception discriminator with multiscale feature extraction ability. Experiments were performed on the Mayo and Piglet datasets, and the results showed that the proposed method outperformed the state-of-the-art denoising algorithms.

Research on accuracy of material identification based on photon counting spectral CT.

Photon counting spectral CT is a significant direction in the development of CT technology and material identification is an important application of spectral CT. However, spectrum estimation in photon counting spectral CT is highly complex and may affect quantification accuracy of material identification. To address the problem of energy spectrum estimation in photon-counting spectral CT, this study investigates empirical material decomposition algorithms to achieve accurate quantitative decomposition of the effective atomic number. The spectrum is first calibrated using the empirical dual-energy calibration (EDEC) method and the effective atomic number is then quantitatively estimated based on the EDEC method. The accuracy of estimating the effective atomic number of materials under different calibration conditions is investigated by designing different calibration phantoms, and accurate quantitation is achieved using suitable calibration settings. Last, the validity of this method is verified through simulations and experimental studies. The results demonstrate that the error in estimating the effective atomic number is reduced to within 4% for low and medium Z materials, thereby enabling accurate material identification. The empirical dual-energy correction method can solve the problem of energy spectrum estimation in photon counting spectral CT. Accurate effective atomic number estimation can be achieved with suitable calibration.

Detection and treatment of thrombotic diseases by activating platelet

Nowadays thrombus has become one of the most prevalent diseases among the world, a large amount of population died of it. Thus, it is essential to improve the medical diagnose and treatment method to lower the morbidity as great as possible. Deep vein thrombus and artery thrombus, these two typical examples of thrombus will be given to illustrate the main methods of diagnose and treatment. In the stage of making diagnose, there are many traditional methods in medical fields like thrombelastogram, radiography, CT technology and X-rays. They are all proven medical technologies which can detect the thrombosis clearly through different principles. However, with the time goes by, Flow Cytometry, a new technology, has been developed through innumerable experiment and research. This technology is significant breakthrough in the history of blooding diagnose since it is more advanced than the classical method in many aspects. For instance, the thrombelastogram has low repeatability since it ‘s results are not always accurate; Radiography will cause risks since it will leave wounds for the patients; CT and X-rays are usually used in the phase of treatment but not in the early diagnose. Above all, it is better to combine these classical means with Flow Cytometry to make the diagnose more convenient and prevent getting thrombus as much as possible. For treatment of thrombus like Deep vein thrombus and artery thrombus, thrombolytic drugs, anticoagulant drugs, and antiplatelet drugs are mainly suggested. Other than those drugs, there are other drugs that may composed by other component are under ongoing research.