Resolution Ultrasonography Research Articles

The Essential Role of Thyroid Scintigraphy and High Resolution Ultrasound for The Etiological Diagnosis of Congenital Hypothyroidism

Congenital hypothyroidism (CH) is the most common congenital endocrine disorder and is a common, preventable cause of mental retardation and growth failure if thyroid hormone replacement is ensured at the proper time and dose. It is well documented that without L-thyroxine replacement from early life, CH causes irreversible neuro-developmental impairment. The three main causes of congenital hypothyroidism are: a) dysembryogenesis, i.e., thyroid dysgenesis, b) dyshormonogenesis and c) transient hypothyroidism. Thyroid dysgenesis includes agenesis and/or the complete absence of the thyroid gland.The diagnosis of CH through new born screening (NBS) program in Bangladesh has greatly contributed to the start of treatment within an adequate time frame since 1999 but the etiological diagnosis is usually delayed until the age of 3 years. This reported case of a 13 years old teenage girl emphasized the importance to find the etiology of her CH diagnosed on day 10 after her birth. The importance of assessing biochemical status of thyroid along with high resolution neck ultrasound (HRUS) and 99mTc-thyroid scintigraphy could change the entire scenario and ensure proper treatment of CH in a place far away from the capital city. Bangladesh J. Nuclear Med. 25(2): 138-142, 2022

Technical note: Evaluation of the acoustic radiation force imaging for predicting HIFU focus with in vitro and ex vivo experiments.

High-intensity focused ultrasound (HIFU) is currently used for the treatment of various diseases, but it still lacks a reliable technique in the preoperative stage to accurately place its "energy blade" onto diseased targets. Acoustic radiation force imaging (ARFI) was recently introduced to tackle this issue, but its applicability and limitations were not clear. The aim of this study was to evaluate the performance of ARFI method in prediction of HIFU focal location at the preoperative stage. A point spread function (PSF) localization method, which was borrowed from the ultrasound super resolution field, was used to validate the core autocorrelation-based motion estimation algorithm in the ARFI procedure. Accuracy of the ARFI method for estimating the HIFU focus were tested with in vitro and ex vivo experiments with a clinically equivalent HIFU system. Comparisons were made between the estimated focal locations and those of the damaged area after the testing objects were cut open. Results showed that the PSF localization was able to serve as a validating method for motion detection only when the tissue displacement was large. With the ARFI method, location of the HIFU focus could be accurately predicted by a 2D motion map preoperatively, and the axial spatial errors were less than 0.5mm. However, the derived 2D motion maps can only be valuable when the acoustic stimulation in ARFI were strong enough, which was probably due to the fact that the HIFU focal locations were at large depths and the ultrasound imaging signal had low signal to noise ratio. The ARFI method was indeed an accurate technique for preoperatively predicting HIFU focus in vitro and ex vivo. If clinical applications were to be considered, particularly in deep tissues, efforts might need to be made to improve ability of the ultrasound motion estimation technique.

Retrospective Ultrasound Doppler Quantification Using a Single Acquisition in Healthy Adults

Using an experimental tool for retrospective ultrasound Doppler quantification-with high temporal resolution and large spatial coverage-simultaneous flow and tissue measurements were obtained. We compared and validated these experimental values against conventional measurements to determine if the experimental acquisition produced trustworthy tissue and flow velocities. We included 21 healthy volunteers. The only exclusion criterion was the presence of an irregular heartbeat. Two ultrasound examinations were performed for each participant, one using conventional and one using experimental acquisition. The experimental acquisition used multiple plane wave emissions combined with electrocardiography stitching to obtain continuous data with over 3500 frames per second. With two recordings covering a biplane apical view of the left ventricle, we retrospectively extracted selected flow and tissue velocities. Flow and tissue velocities were compared between the two acquisitions. Statistical testing showed a small but significant difference. We also exemplified the possibility of extracting spectral tissue Doppler from different sample volumes in the myocardium within the imaging sector, showing a decrease in the velocities from the base to the apex. This study demonstrates the feasibility of simultaneous, retrospective spectral and color Doppler of both tissue and flow from an experimental acquisition covering a full sector width. The measurements were significantly different between the two acquisitions but were still comparable, as the biases were small compared to clinical practice, and the two acquisitions were not done simultaneously. The experimental acquisition also enabled the study of deformation by simultaneous spectral velocity traces from all regions of the image sector.

Comparison of Ultrasonographic Assessment of Cross Sectional Area of the Median Nerve in the Diagnosis of Carpel Tunnel Syndrome with Nerve Conduction Studies

Background: Carpal Tunnel Syndrome (CTS) is a common problem which interferes with the normal use of the hand. It has general population prevalence of 16%. Objective: The objective of this study was to determine the validity of high-resolution ultrasound (US) in carpal tunnel syndrome in adult patients using nerve conduction studies (NCS) as gold standard. Study design & Settings: Cross sectional validation study with purposive (non-probability) sampling conducted in the Department of Diagnostic Radiology, Federal Government Polyclinic Hospital, Islamabad in collaboration with outdoor departments of Neurology and Rheumatology of the same hospital. Study duration: The study was conducted in Federal Government Polyclinic Hospital Islamabad for duration of one year, from November 2021 to November2022. Methods : 152 patients were included in study group who underwent ultrasound by using 12 – 15MHz linear transducer. Later on their nerve conduction studies were performed & results were compared. Results: There were 152 patients included in the study, with 47 (30.9%) males and 105 (69.1%) females and overall mean age of 33.74±11.58 years. The sensitivity of ultrasound to detect carpel tunnel syndrome was calculated to be 90.6% while specificity was found to be 82.52 %. The positive predictive value, negative predictive value and diagnostic accuracy of 86.5%, 87.3% and 86.8% was reported, respectively. Conclusion: High resolution US is an accurate imaging study with diagnostic accuracy of 86.8% and gives results comparable to NCS. It can be used in patients unsuitable for the latter modality. Keywords: Carpel tunnel syndrome (CTS), ultrasound (US), Nerve conduction studies (NCS).

Quantification of limitations in statistical analysis of ultrasound echo envelope amplitudes

Ultrasound echo envelope statistics have been widely studied for quantitative tissue characterization. In ultrasound measurements, the size of the region-of-interest (ROI) is limited by several factors, such as the locality of the tissue characteristics and the depth dependence of the acoustic field of the ultrasound beam. In this case, the evaluated echo envelope statistics vary even when the envelope amplitudes follow the same population without any noise. In this study, the statistical variance of the moments caused by this finite number of samples was quantified based on the central limit theorem and the law of error propagation. The proposed principles were validated by random number simulation and used to quantify the statistical variance of Nakagami parameter estimation. Finally, the effective number of independent samples in an ultrasonic measurement was quantified based on the relationship between the ROI size and the ultrasound spatial resolution.

206 High Resolution Ultrasound for Evaluation of Peripheral Nerve Injuries: Retrospective Examination of an Emerging Technology

INTRODUCTION: Recovery from peripheral nervous system injury (PNI) after trauma has been shown to improve with earlier detection and treatment. Unfortunately, surgical treatments are usually postponed several months after injury due to the need to evaluate for potential recovery without intervention. If diagnostic modalities are able to identify which nerve injuries will require surgical intervention sooner, we may be able to significantly improve outcomes after peripheral nerve injury. High-resolution ultrasound (HRUS) is an imaging modality that potentially could provide this in an economic manner. METHODS: A retrospective chart review was conducted for all patients who received an HRUS of their PNI at our institution from 01/01/2020-01/31/2022. RESULTS: A total of 32 patients were included. The mean age was 45 years with a male predominance (69%). Neuronal and surrounding tissue pathology greater than or equal to the fascicular level could be identified with HRUS. EDx studies were available for 28 (88%) and clinical exams were available for 32 (100%) of patients. Comparing HRUS to the gold standard of a combination of clinical exam and EMG findings, HRUS had a sensitivity of 94% at identifying PNI. Ultimately, 19 (59%) of patients evaluated using HRUS underwent operative intervention. CONCLUSIONS: HRUS is an important emerging imaging modality that can identify and characterize PNI. Our study demonstrates the high sensitivity of HRUS in detecting PNI. Additionally, HRUS in our study identified a number of features that may serve as surrogate markers of injury useful in prognosticating recovery. Further work is needed to define the earliest time point HRUS can be used to identify a PNI.

827 The Use of High Resolution Ultrasound in the Evaluation of Traumatic Peripheral Nerve Injury: A Systematic Literature Review

INTRODUCTION: Traumatic peripheral nerve injury (TPNI) represents a heterogeneous pathology with potential for severe disability. High-resolution ultrasound (HRU) has potential as a non-invasive diagnostic tool to assess injury and inform management decisions, potentially at an earlier time point than traditional electrodiagnostic testing. Standardized assessment of TPNI using HRU is not available in the current literature. We aimed to evaluate the effectiveness of pre-operative HRU in the setting of TPNI through a literature review. METHODS: A systematic literature review was performed adhering to PRISMA guidelines, yielding 84 articles for review. Inclusion criteria included papers that examined ballistic, sharp, and avulsion etiologies of TPNI, and that used ultrasound for initial evaluation of the TPNI. Exclusion criteria included papers with primarily pediatric patients, reviews, meta-analyses, papers not in English, and papers that focused on iatrogenic PNIs. RESULTS: 48 studies met inclusion and exclusion criteria, including 19 case studies, 8 retrospective studies, and 19 prospective studies describing 569 total patients who experienced TPNI. Mean age was 33 years. The studies characterized 121 median, 97 ulnar, 141 radial, and 222 other TPNI from 24 ballistic, 231 sharp, 78 avulsion, and 13 unspecified injuries. The most common HRU findings preoperatively were neuroma formation (79), fascicular swelling (141), and complete discontinuity of epineurium (155). The timing of HRU after TPNI was variable with 37% and 41% of patients undergoing HRU within 6 weeks after TPNI versus more than 6 weeks after TPNI respectively. CONCLUSIONS: HRU is a promising clinical tool for the evaluation of TPNI. Further work is needed to define the appropriate timing for when HRU can be used to evaluate TPNI, as well as radiographic findings that may be clinically relevant in operative evaluations.

Medical ultrasound image speckle reduction and resolution enhancement using texture compensated multi-resolution convolution neural network.

Ultrasound (US) imaging is a mature technology that has widespread applications especially in the healthcare sector. Despite its widespread use and popularity, it has an inherent disadvantage that ultrasound images are prone to speckle and other kinds of noise. The image quality in the low-cost ultrasound imaging systems is degraded due to the presence of such noise and low resolution of such ultrasound systems. Herein, we propose a method for image enhancement where, the overall quality of the US images is improved by simultaneous enhancement of US image resolution and noise suppression. To avoid over-smoothing and preserving structural/texture information, we devise texture compensation in our proposed method to retain the useful anatomical features. Moreover, we also utilize US image formation physics knowledge to generate augmentation datasets which can improve the training of our proposed method. Our experimental results showcase the performance of the proposed network as well as the effectiveness of the utilization of US physics knowledge to generate augmentation datasets.

Nanoparticle-enhanced photoacoustic diagnosis and photothermal treatment of small-animal early-stage liver cancer

Synergy of light and sound, such as photoacoustic imaging, has demonstrated promising potentials in advancing the state-of-the-art of biomedical imaging by ultrasonically detecting the absorption of light, no matter the light is diffusive or not. As a result, optical contrast can be revealed with ultrasound or sub-ultrasound spatial resolution, which can be exploited to map sensitively the early tissue changes associated with the onset and development of early-stage diseases. The sources of photoacoustic emissions, however, could be very complicated within living biological tissue, as many tissue constituents may absorb light and generate heat to emit the ultrasonic waves, which considerably reduces the contrast between the target and the background. Therefore, exogenous agents, such as nanoparticles, that have absorption spectrum distinctive from that of background tissues have been widely used in the field to enhance the photoacoustic detection contrast and sensitivity at selected optical wavelengths. This talk summarizes our recent efforts in this direction that have explored various nanoparticles for more robust and more sensitive diagnosis and treatment of early-stage liver cancer based on photoacoustic imaging and photothermal effect. While the studies are based on merely small animal models, they may inspire further explorations towards preclinical and clinical trials.

Meta-lens with sharp-corner apertures enables super-resolution focusing

By separating the image’s main lobe from its cumbersome sidelobes, the lens can improve far-field ultrasound resolution

Quantitative ultrasound brain imaging with multiscale deconvolutional waveform inversion

High-resolution images of human brain are critical for monitoring the neurological conditions in a portable and safe manner. Sound speed mapping of brain tissues provides unique information for such a purpose. In addition, it is particularly important for building digital human acoustic models, which form a reference for future ultrasound research. Conventional ultrasound modalities can hardly image the human brain at high spatial resolution inside the skull due to the strong impedance contrast between hard tissue and soft tissue. We carry out numerical experiments to demonstrate that the time-domain waveform inversion technique, originating from the geophysics community, is promising to deliver quantitative images of human brains within the skull at a sub-millimeter level by using ultra-sound signals. The successful implementation of such an approach to brain imaging requires the following items: signals of sub-megahertz frequencies transmitting across the inside of skull, an accurate numerical wave equation solver simulating the wave propagation, and well-designed inversion schemes to reconstruct the physical parameters of targeted model based on the optimization theory. Here we propose an innovative modality of multiscale deconvolutional waveform inversion that improves ultrasound imaging resolution, by evaluating the similarity between synthetic data and observed data through using limited length Wiener filter. We implement the proposed approach to iteratively update the parametric models of the human brain. The quantitative imaging method paves the way for building the accurate acoustic brain model to diagnose associated diseases, in a potentially more portable, more dynamic and safer way than magnetic resonance imaging and x-ray computed tomography.

PD41-06 TRANSPERINEAL PROSTATE BIOPSIES USING MICRO-ULTRASOUND, MRI-GUIDED AND SYSTEMATIC BIOPSIES (MADRID PROTOCOL), AN UPDATE WITH 482 PATIENTS

You have accessJournal of UrologyCME1 May 2022PD41-06 TRANSPERINEAL PROSTATE BIOPSIES USING MICRO-ULTRASOUND, MRI-GUIDED AND SYSTEMATIC BIOPSIES (MADRID PROTOCOL), AN UPDATE WITH 482 PATIENTS Moises Elias Socarras, Javier Reinoso Elbers, Fabio Esposito, Isabella Greco, Julio Fernandez del Alamo, Vanesa Cuadros Rivera, Diego Carrion Monsalve, Juan Gomez Rivas, Luis Llanes Gonzalez, and Fernando Gomez Sancha Moises Elias SocarrasMoises Elias Socarras More articles by this author , Javier Reinoso ElbersJavier Reinoso Elbers More articles by this author , Fabio EspositoFabio Esposito More articles by this author , Isabella GrecoIsabella Greco More articles by this author , Julio Fernandez del AlamoJulio Fernandez del Alamo More articles by this author , Vanesa Cuadros RiveraVanesa Cuadros Rivera More articles by this author , Diego Carrion MonsalveDiego Carrion Monsalve More articles by this author , Juan Gomez RivasJuan Gomez Rivas More articles by this author , Luis Llanes GonzalezLuis Llanes Gonzalez More articles by this author , and Fernando Gomez SanchaFernando Gomez Sancha More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002602.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Micro-Ultrasound (micro-US) is a novel high-resolution imaging technology that allows targeting prostate biopsies in real-time to areas of the prostate suspicious of cancer. We aimed to assess the diagnostic yield of combining biopsies targeted by micro-US and mpMRI as well as systematic biopsies (Madrid Protocol). METHODS: We analyzed 482 patients undergoing transperineal prostate biopsies using micro-US and mpMRI targeted and systematic biopsies. We used the Exact-Vu® micro-ultrasound system to perform the micro-US targeted biopsies and the BiopSee® fusion device with standard ultrasound resolution for performing mpMRI and systemic biopsies. We used the McNemar and ANOVA tests for the statistical analysis. RESULTS: Mean age was 63.46±7.91 (58.15-63.75) years, prostate volume was 54.87±(34.75-69) g and PSA was 7.76±6.35 (58.15-69.23) ng/mL respectively. The combination of targeted biopsies with micro-ultrasound + mpMRI + systematic biopsies offered an overall PCa detection rate of 58.92% and csPCa 43.77%, significantly higher than each of the other modalities alone.Micro-US found 11 PCa missed by all other modalities. 9 of these were csPCa GG>1. Moreover, micro-US found 38 PCa missed by MRI and MRI TBx, 26/38 of them csPCa, as well as 21 patients missed by SBx, 16/21 of them csPCa. Therefore, the added value of micro-US beyond MRI TBx is 21.8% and beyond SBX is 8.43%. On the other hand, MRI TBx found 24 PCa lost by SBX, 16/24 of them csPCa and the combination of MRI TBx + SBX found 12 patients not detected by micro-US + SBX, 7/12 of them csPC GG>1. CONCLUSIONS: The use of micro-US combined with mpMRI TBx and systematic biopsies has an excellent diagnostic yield and can be considered complementary, as each modality helps to detect cases missed by the other modalities. Source of Funding: None © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e691 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Moises Elias Socarras More articles by this author Javier Reinoso Elbers More articles by this author Fabio Esposito More articles by this author Isabella Greco More articles by this author Julio Fernandez del Alamo More articles by this author Vanesa Cuadros Rivera More articles by this author Diego Carrion Monsalve More articles by this author Juan Gomez Rivas More articles by this author Luis Llanes Gonzalez More articles by this author Fernando Gomez Sancha More articles by this author Expand All Advertisement PDF DownloadLoading ...

Segmentation and Quantitative Analysis of Photoacoustic Imaging: A Review

Photoacoustic imaging is an emerging biomedical imaging technique that combines optical contrast and ultrasound resolution to create unprecedented light absorption contrast in deep tissue. Thanks to its fusional imaging advantages, photoacoustic imaging can provide multiple structural and functional insights into biological tissues such as blood vasculatures and tumors and monitor the kinetic movements of hemoglobin and lipids. To better visualize and analyze the regions of interest, segmentation and quantitative analyses were used to extract several biological factors, such as the intensity level changes, diameter, and tortuosity of the tissues. Over the past 10 years, classical segmentation methods and advances in deep learning approaches have been utilized in research investigations. In this review, we provide a comprehensive review of segmentation and quantitative methods that have been developed to process photoacoustic imaging in preclinical and clinical experiments. We focus on the parametric reliability of quantitative analysis for semantic and instance-level segmentation. We also introduce the similarities and alternatives of deep learning models in qualitative measurements using classical segmentation methods for photoacoustic imaging.

Twin Reversed Arterial Perfusion Sequence.

Twin Reversed Arterial Perfusion Sequence.

Photoacoustic imaging systems based on clinical ultrasound platform.

Photoacoustic imaging has drawn a significant amount of attention due to its unique capacity for functional, metabolic, and molecular imaging, which is achieved by the combination of optical excitation and acoustic detection. With both strengths of light and ultrasound, photoacoustic images can provide strong optical contrast at high ultrasound resolution in deep tissue. As photoacoustic imaging can be used to visualize complementary information to ultrasound imaging using the same data acquisition process, several studies have been conducted on combining photoacoustic imaging with existing clinical ultrasound systems. This review highlights our development of a photoacoustic/ultrasound dual-modal imaging system, various features and functionalities implemented for clinical translation, and preclinical/clinical studies performed by using the systems.

VECTOR: An algorithm for the detection of COVID-19 pneumonia from velcro-like lung sounds

The coronavirus disease 2019 (COVID-19) has severely stressed the sanitary systems of all countries in the world. One of the main issues that physicians are called to tackle is represented by the monitoring of pauci-symptomatic COVID-19 patients at home and, generally speaking, everyone the access to the hospital might or should be severely reduced. Indeed, the early detection of interstitial pneumonia is particularly relevant for the survival of these patients. Recent studies on rheumatoid arthritis and interstitial lung diseases have shown that pathological pulmonary sounds can be automatically detected by suitably developed algorithms. The scope of this preliminary work consists of proving that the pathological lung sounds evidenced in patients affected by COVID-19 pneumonia can be automatically detected as well by the same class of algorithms. In particular the software VECTOR, suitably devised for interstitial lung diseases, has been employed to process the lung sounds of 28 patient recorded in the emergency room at the university hospital of Modena (Italy) during December 2020. The performance of VECTOR has been compared with diagnostic techniques based on imaging, namely lung ultrasound, chest X-ray and high resolution computed tomography, which have been assumed as ground truth. The results have evidenced a surprising overall diagnostic accuracy of 75% even if the staff of the emergency room has not been suitably trained for lung auscultation and the parameters of the software have not been optimized to detect interstitial pneumonia. These results pave the way to a new approach for monitoring the pulmonary implication in pauci-symptomatic COVID-19 patients.

Ultrasound-Based Navigation for Open Liver Surgery with Active Tumor Tracking and Deformation Compensation: Preliminary Results

Introduction: Intraoperative ultrasound (US) localization of lesions after neoadjuvant chemotherapy is challenging because their size may decrease beyond the ultrasound resolution. To improve their localization, we introduce an ultrasound-based electromagnetic (EM) navigation system which maps the preoperative image with the intraoperative ultrasound, thus highlighting their location. Methods: Based on MRI or CT, a 3D model of the liver, lesions, hepatic and portal vein was generated and matched with the intraoperative organ position either by 1) identifying common landmarks between the pre- and intraoperative image or 2) automatically using deformable modeling of hepatic and portal vasculature extracted from 3DUS using deep learning. Accuracy was assessed as Euclidean distance between the lesion imaged in the preoperative image and the one identified in intraoperative 3DUS. Results: From March 2019 to May 2021, 45 navigated procedures were safely performed. Navigation provided additional localization features by overlaying preoperative 3D models of liver lesions, vasculature and biliary anatomy onto the intraoperative ultrasound. Accuracy, calculated in 36 patients, was 8.5 ± 4.2 mm for the landmark method (n=20), and 5.7 ± 3.6 mm for automatic generation of the vasculature (n=16) (p=0.043). Surgical navigation was available on average after 13.4 minutes. Conclusion: The proposed navigation system allows to accurately localize liver lesions and is improved by automatic vasculature detection in the US image and compensation of respiratory motion and liver manipulation.

Characterization of the Ultrasound Localization Microscopy Resolution Limit in the Presence of Image Degradation.

Ultrasound localization microscopy (ULM) has been able to overcome the diffraction limit of ultrasound imaging. The resolution limit of ULM has been previously modeled using the Cramér-Rao lower bound (CRLB). While this model has been validated in a homogeneous medium, it estimates a resolution limit, which has not yet been achieved in vivo. In this work, we investigated the effects of three sources of image degradation on the resolution limit of ULM. The Fullwave simulation tool was used to simulate acquisitions of transabdominal contrast-enhanced data at depth. The effects of reverberation clutter, trailing clutter, and phase aberration were studied. The resolution limit, in the presence of reverberation clutter alone, was empirically measured to be up to 39 times worse in the axial dimension and up to 2.1 times worse in the lateral dimension than the limit predicted by the CRLB. While reverberation clutter had an isotropic impact on the resolution, trailing clutter had a constant impact on both dimensions across all signal-to-trailing-clutter ratios (STCR). Phase aberration had a significant impact on the resolution limit over the studied analysis ranges. Phase aberration alone degraded the resolution limit up to 70 and 160 [Formula: see text] in the lateral and axial dimensions, respectively. These results illustrate the importance of phase aberration correction and clutter filtering in ULM postprocessing. The analysis results were demonstrated through the simulation of the ULM process applied to a cross-tube model that was degraded by each of the three aforementioned sources of degradation.

High Resolution Ultrasound in Entrapment Neuropathies of Ulnar Nerve- A Case Series

Ulnar nerve is one of the terminal branches of the medial cord of brachial plexus. Owing to its superficial location and unprotected course ulnar nerve is susceptible to physical impingement at specific sites. Although clinical and electrophysiological assessment can diagnose ulnar neuropathy and site of compression, they do not provide aetiological information which is important for management. High Resolution Ultrasonography (HRUS) is a non invasive imaging tool that has been used widely to evaluate peripheral nerves. In this case series, HRUS imaging findings in seven distinct cases of entrapment of ulnar nerve or its branches are presented. In cases 1, 2, 3 and 4, ulnar nerve was entrapped at the elbow; by synovial thickening due to degeneration, claw osteophyte arising from ulna, synovial cyst and epineural ganglion cyst respectively. In cases 5 and 6, ulnar nerve was entrapped at the wrist by a pisotriquetral ganglion cyst and an ulnar artery pseudoaneurysm respectively. In case 7 the Dorsal Cutaneous Branch (DCB) of ulnar nerve was entrapped over the Extensor Carpi Ulnaris (ECU) tendon. In all the aforementioned cases, HRUS accurately identified the site of entrapment, the status of ulnar nerve and the underlying cause of entrapment, which was subsequently confirmed surgically. The non invasive, inexpensive and accurate qualities make HRUS a potential first line imaging tool in the evaluation of entrapment neuropathies of superficial nerves.

High Resolution Ultrasound of Fillers and Their Implications in Aesthetic Medicine: A Study in Human Cadavers

The use of fillers for cosmetic or therapeutic purposes is very common and it’s increasing daily. Although it’s true that in most cases the results are as expected, the use of these substances is not free from the development of complications, even when it’s performed by highly trained medical physicians. On the other hand, these substances can be used indiscriminately by untrained personnel leading to a serious public health complication known as iatrogenic allogenosis, which leads to problems related to malpractice. Most of the time, professionals are consulted for a second opinion regarding the use of these substances, because use of these substances might be unknown due to the patients denying or forgetting the use of these. The presence of a previous unknown filler in aesthetic areas that require treatment may trigger severe or irreversible reactions, especially if non-absorbable fillers were injected. High resolution ultrasound is an extremely useful diagnostic tool for the identification of fillers. In this paper we will describe the ultrasound appearance of hyaluronic acid, calcium hydroxyapatite, liquid silicone, silicone oil, biopolymers, and Polymethylmethacrylate (PPMA) and then we compare it with it’s reported appearance in previous studies. The injection of the substances was carried out in human cadavers with the intention of gathering ultrasound images as similar to the imaging behavior of these substances in vivo. The obtained images can be used as precise references in the ultrasound evaluation, diagnosis, follow-up and behavior of the filler materials in the benefit of a comprehensive approach in the management of patients.