Diagnostic Imaging Techniques Research Articles

Geometrical Analysis of the Stagnation Zone in Laterally Colliding Plasmas: Effects of Plasma Plume Separation and Ablating Target Material

The influence of an ablating target’s atomic mass on the development and growth of the interaction zone in laterally colliding plasmas has been investigated. As diagnostic tools, fast imaging and optical emission techniques were used to evaluate the characteristics of the seed plasma as well as the interaction zone created by different target materials (i.e., aluminum and silicon). The current findings show that the dynamical, spectral, and geometrical properties of the generated interaction zone are affected by the features of the ablated species and the geographical separation of the interacting plumes. The interaction of aluminum plume species results in a sharper, more intense, and more directed stagnation zone than that reported for silicon targets using a 450 nm filter. Furthermore, the investigation of the interaction area emission from both regions for aluminum (Al) and silicon (Si) plasma explains the variation in plasma properties in the stagnation zone. As a part of this work’s description, a comparative study of the dynamics and characteristics of the homogenous interaction region produced by colliding plasma plumes by laser ablation of flat Al and Si targets has been presented, which can provide deep insight into the characterization of colliding laser-produced plasma expansion and related physical and technical properties.

Naphth[1,2-d]imidazoles Bioactive from β-Lapachone: Fluorescent Probes and Cytotoxic Agents to Cancer Cells

Theranostics combines therapeutic and imaging diagnostic techniques that are extremely dependent on the action of imaging agent, transporter of therapeutic molecules, and specific target ligand, in which fluorescent probes can act as diagnostic agents. In particular, naphthoimidazoles are potential bioactive heterocycle compounds to be used in several biomedical applications. With this aim, a group of seven naphth[1,2-d]imidazole compounds were synthesized from β-lapachone. Their optical properties and their cytotoxic activity against cancer cells and their compounds were evaluated and confirmed promising values for molar absorptivity coefficients (on the order of 103 to 104), intense fluorescence emissions in the blue region, and large Stokes shifts (20-103 nm). Furthermore, the probes were also selective for analyzed cancer cells (leukemic cells (HL-60). The naphth[1,2-d]imidazoles showed IC50 between 8.71 and 29.92 μM against HL-60 cells. For HCT-116 cells, values for IC50 between 21.12 and 62.11 μM were observed. The selective cytotoxicity towards cancer cells and the fluorescence of the synthesized naphth[1,2-d]imidazoles are promising responses that make possible the application of these components in antitumor theranostic systems.

K-18 Diagnostic imaging techniques applied on farms

K-18 Diagnostic imaging techniques applied on farms

Negative Appendectomies: Evaluating Diagnostic Imaging Techniques at General versus Pediatric Emergency Departments

BackgroundAlthough appendicitis is the most common pediatric surgical emergency, the path to diagnosis remains equivocal, with utilization of imaging modalities largely institution dependent. ObjectivesOur objective was to compare imaging practices and negative appendectomy rates between patients transferred from nonpediatric hospitals to our pediatric hospital and primary patients presenting directly to our institution. MethodsWe retrospectively reviewed all laparoscopic appendectomy cases performed at our pediatric hospital in 2017 for imaging and histopathologic results. Two-sample z-test was used to examine negative appendectomy rates between transfer and primary patients. The negative appendectomy rates of patients who received different imaging modalities were analyzed using the Fisher's exact test. ResultsOf 626 patients, 321 (51%) were transferred from nonpediatric hospitals. The negative appendectomy rate for transfer patients was 6.5% and 6.6% for primary patients (p = 0.99). Ultrasound (US) was the only imaging obtained in 31% of transfer and 82% of primary patients. The negative appendectomy rate of US performed at transfer hospitals compared with our pediatric institution was not significantly different (11% vs. 5%, p = 0.06). Computed tomography (CT) was the only imaging obtained in 34% of transfer and 5% of primary patients. Both US and CT were completed for 17% of transfer and 19% of primary patients. ConclusionThe negative appendectomy rates of transfer and primary patients were not significantly different despite more frequent CT use at nonpediatric facilities. It may be valuable to encourage US utilization at adult facilities given the potential to safely reduce CT use in the evaluation of suspected pediatric appendicitis.

The subharmonic resonance of lipid-encapsulated ultrasound contrast agents

A salient feature of ultrasound contrast agent echo is their subharmonic response, a property that can be exploited for diagnostic contrast imaging. Here, we aim to explore the subharmonic behavior, specifically the subharmonic resonance, of two identical lipid-encapsulated microbubbles in close proximity to each other (center-to-center h = 6–16 μm) using finite element modeling. We simulated the subharmonic resonance response for bubbles (R0 = 0.5–1.5 μm) driven with 10 or 20 cycle tone bursts from 6 to 18 MHz under a peak negative pressure from 40to 180 kPa over a range of initial phospholipid packing values (σ0 = 0–0.01 N/m). Our results demonstrate that for increasing pressure, the transmit frequency at which the peak in subharmonic response is observed shifts monotonically towards higher frequencies (1–10%) for bubbles close to their buckling point, while the opposite trend occurs for bubbles with less dense initial packing (1–15%). For intermediate values of initial packing, a two-stage response is observed whereby the transmit frequency first decreases and then increases (5–9%) with increasing pressure. These results have implications in subharmonic-based diagnostic imaging techniques.

Screening and Early Diagnosis of Hepatocellular Cancer and Optimization of Diagnostic Imaging Techniques: A Review and Conclusion of the Expert Panel

Аim: to describe modern approaches for screening and early diagnosis of hepatocellular carcinoma (HCC).Key points. Screening for HCC in high-risk groups (cirrhosis of any etiology, patients with chronic viral hepatitis B and patients with F3 liver fibrosis) should be organized as regular (every 6 months) liver ultrasound in combination with determination of the serum alpha-fetoprotein (AFP) level. At an AFP level of ≥ 20 ng/ml, even in the absence of changes according to ultrasound data, it is advisable to perform MRI with a hepatospecific contrast agent (gadoxetic acid) which makes it possible to detect very small focal liver lesions. If focal liver lesions of 1–2 cm are detected on ultrasound, additional imaging of the liver using MRI with a hepatospecific contrast agent gadoxetic acid helps to identify HCC at an earlier stage or high degree dysplastic nodes. When planning surgical treatment and liver transplantation, it is preferable to use MRI with a hepatospecific contrast agent, since the presence of the hepatobiliary phase may allow the detection of additional smaller focal liver lesions and assess the nature of the focal liver lesion. When a patient is included in the waiting list for liver transplantation, the optimal frequency of liver MRI is 1 time in 3 months.Conclusion. MRI with hepatospecific contrast agent gadoxetic acid is effective in screening, early diagnosis and treatment planning for HCC.

Melanoma and Nevi Subtype Histopathological Characterization with Optical Coherence Tomography.

Melanoma incidence has continued to rise in the latest decades, and the forecast is not optimistic. Non-invasive diagnostic imaging techniques such as optical coherence tomography (OCT) are largely studied; however, there is still no agreement on its use for the diagnosis of melanoma. For dermatologists, the differentiation of non-invasive (junctional nevus, compound nevus, intradermal nevus, and melanoma in-situ) versus invasive (superficial spreading melanoma and nodular melanoma) lesions is the key issue in their daily routine. This work performs a comparative analysis of OCT images using haematoxylin-eosin (HE) and anatomopathological features identified by a pathologist. Then, optical and textural properties are extracted from OCT images with the aim to identify subtle features that could potentially maximize the usefulness of the imaging technique in the identification of the lesion's potential invasiveness. Preliminary features reveal differences discriminating melanoma in-situ from superficial spreading melanoma and also between melanoma and nevus subtypes that pose a promising baseline for further research. Answering the final goal of diagnosing non-invasive versus invasive lesions with OCT does not seem feasible in the short term, but the obtained results demonstrate a step forward to achieve this.

Quantitative Diagnosis Progress of Ultrasound Imaging Technology in Thyroid Diffuse Diseases.

High-frequency ultrasound (HFUS), the imaging modality of choice for thyroid screening, is most commonly used in the study of diffuse thyroid disease (DTD) with Hashimoto's thyroiditis (HT) and Graves' disease (GD). DTD can involve thyroid function and severely affect life quality, so early diagnosis is important for the development of timely clinical intervention strategies. Previously, the diagnosis of DTD relied on qualitative ultrasound imaging and related laboratory tests. In recent years, with the development of multimodal imaging and intelligent medicine, ultrasound and other diagnostic imaging techniques have gradually become more widely used for quantitative assessment of the structure and function of DTD. In this paper, we review the current status and progress of quantitative diagnostic ultrasound imaging techniques for DTD.

Advances in imaging of the equine distal limb: 2017–2022 EVJ, EVE and VRU updates

Injuries and diseases of the distal limb constitute the commonest causes of lameness in horses, and diagnostic imaging plays a central role in their diagnosis. There have been tremendous advances in the development and application of diagnostic imaging techniques used to evaluate the distal limbs in the past 15–20 years, with advanced cross-sectional imaging modalities, such as magnetic resonance imaging (MRI) and computed tomography (CT), being increasingly utilised to provide diagnostic information, in combination with the more ‘traditional’ techniques of radiography and ultrasonography. These new imaging techniques do not replace radiography and ultrasonography but complement them – indeed each technique has its own advantages and limitations. Like many advances in veterinary medicine, these imaging modalities have transferred from their use in other areas, including human medicine, to use in animals. The initial reliance on MRI and CT scanners designed for use in people (which generally require the equine patient to be imaged whilst under general anaesthesia) has now evolved into scanners that can be used to image the distal limb in standing horses, thereby increasing their practicality and availability in equine practice. The advanced imaging ‘stable’ of MRI and CT has recently been strengthened by the introduction of positron emission tomography (PET), which will undoubtedly add to and further refine our diagnostic capabilities for conditions of the distal limb in the next 5 years. Equine Veterinary Education (EVJ), Equine Veterinary Journal (EVJ) and Veterinary Radiology and Ultrasound (VRU) have joined forces to publish a virtual issue on advances in diagnostic imaging of the distal limb, highlighting a selection of some of the more interesting and important article published in these three journals over the past 5 years. This is the second joint issue that we have published, following on from the issue that we published in 2016, which reviewed articles focused on imaging of the head and neck. The three guest editors for the current virtual issue were Mathieu Spriet (on behalf of EVJ), Ann Carstens (on behalf of VRU) and Tim Mair (on behalf of EVE). Their challenge was to select ‘articles that give novel important information that is clinically relevant and applicable to the limb of the horse from the metacarpo/tarso-phalangeal joint and distally’. We hope that this virtual issue will provide a useful and informative review of some of the exciting developments in diagnostic imaging of the distal limb that have occurred recently. With the ever-increasing technological improvements and availability of diagnostic imaging equipment, we can look forward to further advances in the coming years, which will continue to contribute to improved equine welfare by assisting in the prevention and treatment of diseases of the distal limbs.

Intracoronary Diagnostics in Patients with Acute Coronary Syndrome.

Despite the increasing number of coronary interventions in China, long-term adverse cardiovascular events remain high, especially in patients with acute coronary syndromes (ACS). The advent of intracoronary imaging and coronary physiological diagnostic techniques, such as optical coherence tomography (OCT), intravascular ultrasound (IVUS), near infrared spectroscopy (NIRS), and flow reserve fraction (FFR), has optimized the diagnosis and risk classification of patients with ACS. Intracoronary diagnostics compensate for the deficiencies of conventional coronary angiography in identifying and incriminating lesions and high-risk lesions. The combination of intracoronary imaging and physiological techniques is expected to achieve a comprehensive evaluation of the structural features and physiology of the coronary arteries, thus further tailoring and improving the prognosis of patients.

Cardiac Sarcoidosis: A Contemporary Concept of Forgotten Granulomatosis.

Sarcoidosis is a complex multisystem inflammatory granulomatous disease that can affect any organ, with a wide range of clinical presentations. A significant number of patients with systemic sarcoidosis may also have cardiac involvement. Clinical manifestations of cardiac sarcoidosis can include various rhythm and conduction disturbances, as well as heart failure. The structure of sarcoid granulomas is similar to that of tuberculous granulomas, but in contrast, they lack caseous necrosis. Tissue changes in sarcoidosis tissues depend on the stage of development of the disease, progressing from pathological process: macrophage-lymphocytic infiltration to epithelioid cell granuloma formation, and fibrosis. Granulomas can be found in any part of the myocardium, with the most common locations being the free wall of the left ventricle, the basal part of the interventricular septum, and the interatrial septum. Vasculopathy of the pulmonary circulation and coronary arteries is often observed. Advancements in diagnostic imaging techniques, such as computer tomography and magnetic resonance imaging, have facilitated the verification of cardiac sarcoidosis. This article presents an analysis of updated information on cardiac sarcoidosis by a multidisciplinary working group.

An Ultrasonic Adaptive Beamforming Method and Its Application for Trans-Skull Imaging of Certain Types of Head Injuries; Part II: Reception Mode and Adaptive Imaging.

Background theory and a new algorithm for single-point adaptive focusing in transmission mode through ultrasonic barriers via one-dimensional phased arrays were reported in part I. In this paper the algorithm is further extended and implemented into a full adaptive beamforming process, including complete transmission and reception modes. Corrected time delay patterns, adapted to the local acoustical and geometrical properties of the barrier, are calculated and applied in both modes. Further, an adaptive imaging process is also developed that implements the proposed beamforming process for two-dimensional imaging through randomly shaped multilayered phase-aberrating structures. The method is optimized for the case of human skull as the ultrasound barrier and its application for transcranial imaging is discussed. Laboratory results of adaptive imaging through realistic skull-mimicking phantoms are presented. The algorithms are implemented on a 64-channel ultrasound open-source phased array platform controlling a standard 128-element biomedical phased array. Irregularly shaped reflectors with characteristic dimensions of the order of ∼0.5 mm to ∼4.5 mm were used as targets behind the skull phantoms in our experiments. Minimum and maximum distortional target displacements of 2.2 mm and 25.3 mm (in 12 cm depth) were observed in sonograms when uncompensated time delays were used. By contrast, the positioning errors ranged from 0.0 to 0.9 mm when our algorithm was employed. The adaptive imaging results demonstrate strong potential of the proposed technique for diagnostic imaging of acoustically reflective head injuries directly through intact human skull.

RCS Diagnostic Imaging Using Parameter Extraction Technique of State Space Method

AbstractThe signature extraction and processing are the key aspects of enhancing recognition ability for radar target characteristics. In this paper, to reveal the intrinsic property of the target and improve the accuracy of radar cross section (RCS), we proposed RCS diagnostic imaging technique, extracting the parameters of scattering center model by state space method (SSM), to analyze the signature of GTD‐based returns. To demonstrate the effectiveness of SSM, the comparison with estimating signal parameter via rotational invariance techniques method by the analysis of goodness‐of‐fit and root mean square error, reconstructing the RCS profile through original signal model, and employing SSM to extract the signature of specular and creeping wave from the PEC sphere. Furthermore, the RCS diagnostic imaging by SSM extracting position and amplitude is discussed, and range‐isolated pole technique specific to the creeping wave extraction is addressed the advantage of SSM.

Development and validation of a method for creating incomplete vertical root fracture in extracted teeth.

The present study reported a method for inducing incomplete root fracture in human extracted teeth for the purpose of evaluating the merits of different diagnostic imaging techniques. Thirty-five single-rooted teeth were inspected under magnification and transillumination to exclude previously fractured teeth. Tooth crowns were removed, and the root canals were prepared up to the ProTaper Next X4 (40.06) file. Each root was lined with wax and embedded in a polystyrene resin block. The setup was attached to a universal testing machine for pressing a customized conical wedge (diameter at tip: 0.6mm; taper: 0.2mm/mm) into the instrumented canal with a 2kN load at 5mm/min. The machine was programmed to stop after a sudden 10% drop in loading force. Each specimen was removed from the resin block and inspected under × 20 magnification and transillumination to identify the fracture characteristics (pattern, surfaces and root-third affected). The gap width of each specimen was measured at different locations along the fracture line. The protocol induced incomplete vertical root fractures in all specimens. Fracture widths were < 100μm in all specimens (mean gap width: 34.9μm). The proposed methodology was successful in inducing incomplete vertical root fractures with characteristics that resemble the clinical presentation of these conditions. The method is easy to execute, highly reproducible and helps to minimize bias in laboratory studies that aims to mimic vertical root fractures.

Optimization of staging algorithm for newly detected prostate cancer by using PET/CT with &lt;sup&gt;68&lt;/sup&gt;Ga-PSMA: a retrospective study

INTRODUCTION: Prostate cancer (PC) is the most common malignancy in men worldwide and ranks third in mortality. Improvement of the results of staging of newly detected prostate cancer is rightfully associated with the active use in clinical practice of positron emission tomography combined with computed tomography (PET/CT) with radiotracers based on prostate-specific membrane antigen (PSMA) ligands.OBJECTIVE: The aim of the study was to determine the capabilities of PET/CT with 68Ga-PSMA in evaluating the prevalence of newly diagnosed breast cancer in comparison with traditional imaging techniques (computed tomography, magnetic resonance imaging and bone scan) and to determine the role of this technology in the choice of treatment algorithm.MATERIALS AND METHODS: 120 patients aged 46 to 74 years (median age 62.5 years) with histologically verified prostate cancer underwent PET/CT with 68Ga-PSMA in our center to assess disease prevalence. The selection criteria for the study were: prostate-specific antigen (PSA) level of 5 ng/ml and above, presence of newly detected, histologically verified prostate cancer, no treatment, suspected metastatic lesion of pelvic and skeletal lymph nodes according to CT, MRI and OSG. All patients were divided into groups according to PSA level and Gleason score. Statistics: Statistical processing of the results was performed by methods of variance statistics using Statistica 10.0, GraphPad Prism 9.3.1. Wilcoxon-Mann-Whitney and Friedman tests for ANOVA were used to determine the significance of differences between comparison groups. The chi-square test with Yates correction was used to determine the reliability of intergroup differences for nominal measures (such as the presence of previous recurrences). The level of correlation was assessed using Spearman criterion.RESULTS: PET/CT imaging analysis in addition to MRI, CT, and OSG data showed TNM staging changes in 63 of 120 patients (52.3%) due to the detection of additional foci of metastatic lesions. Change of data about local spread of tumor with increasing of TNM stage due to detection of pathological RFP accumulation in seminal vesicles in 10 of 120 patients (8.3%), without structural changes using conventional imaging methods. In 20 of 64 patients (31.3%), PET/CT revealed lesions of regional lymph nodes (N) that were not visualized by conventional imaging methods due to their small size. Metastatic lesions of distant lymph nodes (M1a) and bones (M1b) undetected by CT, MRI, and OSG were found in 27 (22.5%) and 32 (26.7%) of 120 patients, respectively. At the same time, foci of pathological accumulation of 68Ga-PSMA in the bones without structural changes on CT were detected in 7 and 32 patients (21.8%).DISCUSSION: One of the objectives of this study was to compare the diagnostic capabilities of standard diagnostic imaging techniques, in particular MRI, CT and Bone scan, with the hybrid technology of PET/CT with 68Ga-PSMA to improve the accuracy of PCa staging in order to determine treatment tactics. The results demonstrate minimal superiority of PET/CT with 68Ga-PSMA over MRI in terms of sensitivity (96% and 94%, respectively) in assessing local disease prevalence. Tumor invasion of the seminal vesicles, in most cases, was detected in patients with a Gleason score greater than 8. At the same time there was a tendency for an increase in the level of radiotracer accumulation in the tumor tissue of the seminal vesicles depending on the differentiation group of PCa. Analysis of the histological material obtained after the prostatectomy demonstrated tumorous invasion of the seminal vesicles in 26 (37.1%) out of 70 operated patients. Coincidence of histological examination results with PET/CT data was found in 22 patients, with MRI data — in 20 patients. The sensitivity, specificity, positive predictive value, and negative predictive value of PET/CT were 85%, 92%, 85%, and 92%, while the corresponding values from MRI were as follows: 77%, 88%, 77%, and 88%. Analyzing the levels of 68Ga-PSMA uptake in the tumor tissue, we found that with increasing prostate differentiation group, there was a persistent increase in radiotracer accumulation in the prostate tumor tissue. We also evaluated the interrelation of RFP accumulation with PSA level. The patients with PCa with PSA level ≥10.0 ng/ml demonstrated high accumulation of radiotracer accumulation compared to those with PSA &lt;10.0 ng/ml (p&lt;0.001).CONCLUSIONS: The use of 68Ga-PSMA PET/CT in the staging of newly diagnosed and untreated cancers provides comprehensive information on the local, regional, and distant extent of the disease, and in some cases contributes to a change in TNM stage of the disease in a single study. The use of this method before planned surgical treatment of PCa can significantly reduce the risk of early postoperative relapse, especially in patients with a Gleason score of more than 7 and a PSA level greater than 20 ng/ml.

Use of Computed Tomography in Evaluation and Management of Shell Fracture in a Red Eared Slider Turtle ( Trachemys scripta elegans) A Case report

Traumatic lesions of the shell are common problems in chelonians. Lesions of the shell vary in severity from a simple superficial abrasion (with a loss of the external skin layer and exposure of the bone) to complicated fractures of the carapace with exposure of internal organs of the coelom and injury of the soft tissues (Barten, 2006). In most shell or skeletal injuries in the turtle, plain radiographic data do not reveal the extent of complex fractures due to superimposed bone structures (Abou-Madi et al., 2002). In Comparison with conventional radiography, computed tomography (CT) allows better distinction of specific tissue densities and discrete changes in organ size, shape, margin, contour and position (Gaudron et al., 2001). Computed tomography is a non-invasive, cross-sectional diagnostic imaging technique that offers significant advantages for detection of pathologies in chelonians, and is ideal for diagnosing skeletal and soft tissue abnormalities (Gumpenberger and Henninger, 2001). The aim of the present work was to evaluate the three dimensional computed tomography (CT) for clinical examination of shell lesions in a red eared slider turtle.

Morphometric and Normal 2D CT Anatomic Study of the Vertebral Column of the European Pond Turtle (Emys orbicularis)

Background: European pond turtle is one of the two species of freshwater turtles in Iran. Regarding clinical examinations and diagnostic imaging techniques, it is necessary to have complete anatomical information on this turtle. Objectives: This study provided complete morphometric and normal two-dimensional computerized tomographic scanning information of the vertebrae of European pond turtles. Methods: Ten European pond turtles were used in this study. Computerized tomography (CT) scans were taken from each anesthetized turtle. Then, morphometric parameters were measured in the CT scans of the vertebral column. Results: Atlas was the shortest of the cervical vertebrae, and the eighth cervical vertebra was shorter than the previous vertebrae. The articular surface of the caudal articular processes of the eighth cervical vertebra was bent, and these surfaces were almost vertical. Transverse process width had remained constant in the cervical vertebrae. The transverse process was not observed in the dorsal vertebrae. The first dorsal vertebra had a different shape than others. Conclusion: The particular shape of the last two cervical vertebrae, especially the arched shape of the eight vertebrae. The seventh and eighth cervical vertebrae have the largest transverse distance between caudal articular processes that seem necessary for cervical motion. The limited space of the caudal cervical vertebrae inside the shell chamber can be the reason for the reduction in the length of these vertebrae. The absence of a spinous process in the seventh and eighth cervical vertebrae of the neck may be related to their specific position in the neck retraction.

Transcranial Doppler analysis based on computer and artificial intelligence for acute cerebrovascular disease

Cerebrovascular disease refers to damage to brain tissue caused by impaired intracranial blood circulation. It usually presents clinically as an acute nonfatal event and is characterized by high morbidity, disability, and mortality. Transcranial Doppler (TCD) ultrasonography is a non-invasive method for the diagnosis of cerebrovascular disease that uses the Doppler effect to detect the hemodynamic and physiological parameters of the major intracranial basilar arteries. It can provide important hemodynamic information that cannot be measured by other diagnostic imaging techniques for cerebrovascular disease. And the result parameters of TCD ultrasonography such as blood flow velocity and beat index can reflect the type of cerebrovascular disease and serve as a basis to assist physicians in the treatment of cerebrovascular diseases. Artificial intelligence (AI) is a branch of computer science which is used in a wide range of applications in agriculture, communications, medicine, finance, and other fields. In recent years, there are much research devoted to the application of AI to TCD. The review and summary of related technologies is an important work to promote the development of this field, which can provide an intuitive technical summary for future researchers. In this paper, we first review the development, principles, and applications of TCD ultrasonography and other related knowledge, and briefly introduce the development of AI in the field of medicine and emergency medicine. Finally, we summarize in detail the applications and advantages of AI technology in TCD ultrasonography including the establishment of an examination system combining brain computer interface (BCI) and TCD ultrasonography, the classification and noise cancellation of TCD ultrasonography signals using AI algorithms, and the use of intelligent robots to assist physicians in TCD ultrasonography and discuss the prospects for the development of AI in TCD ultrasonography.

Vascular Malformations in Paediatric Age Group: Learning through Mistakes

Vascular malformations were known in all paediatric age groups including neonates to adolescence. These were known since very long time. Many such cases were missed earlier due to lack of diagnostic imaging techniques. Proper diagnosis of such lesions is very challenging. So, proper identification and early treatment is of utmost importance. Any misdiagnosis can lead to inappropriate management and outcome. With recent advances in imaging techniques and better interventional facilities, the rate of diagnosis has improved but still the rate of misdiagnosis remains high. Though the newer treatment modalities are available, but their availability is restricted to tertiary care multifacility hospitals. Therefore, even after proper diagnosis, the management remains inadequate. This series is about three different patients of vascular malformations, belonging to different paediatric age groups. The clinical presentations, diagnosis and management were varied but diagnosis was possible due to high level of clinical suspicion and modern imaging techniques. The first patient initially seemed to have a post-traumatic swelling or juvenile idiopathic arthritis, but was later diagnosed as peripheral vascular malformation. The second patient was suspected to have haemangioma, but final diagnosis based on radiographical findings revealed low flow vascular malformation of face. The third patient was diagnosed with vascular malformation of head, but was clinically thought to be a sebaceous cyst.

Tomografía Computarizada Espectral y unidades Hounsfield: bases para una correcta interpretación

Dual energy CT is a recent upgrade to this diagnostic imaging technique. The purpose of this critical narrative review is to lay out the clinical applications of Hounsfield Units and their variation across the x-ray energy spectrum using DECT. We explore new reconstruction methods and parametric maps helpful for the diagnosis of prevalent pathologies such as fatty liver disease, urolithiasis, and to identify complications after interventions or determine the aggressiveness of tumoral lesions. The energy-resolving capabilities of DECT make it a reliable method for the characterisation of tissue and lesion composition. Lower energy monoenergetic images allow us to increase soft tissue contrast and easily identify tissues with higher contrast uptake. Higher energy monoenergetic images are useful to distinguish between contrast uptake and high attenuation calcium deposits and for metal artifact reduction. Parametric images showing uric acid, iodine, calcium, and other material decompositions can be obtained from spectral data for the diagnosis of tumoral or metabolic diseases, vascular lesions and characterisation of deposition arthritis and urolithiasis.