Imaging Methods For Early Diagnosis Research Articles

Significance of identifying the location and nature of lesion in imaging diagnosis of diplopia

Objective: Identifying the lesion location and nature and selecting appropriate imaging methods for early diagnosis of diplopia and treatment. Methods: The data of 3 patients with diplopia were collected, including basic information and clinical features, anatomical location and imaging examination, treatment and effect. Results: Three cases of diplopia were diagnosed by head CT and MRI. Based on gender, age, symptoms, signs and disease development, the location and nature of the lesions were inferred. It had an important impact on imaging diagnosis, treatment and prognosis. Conclusion: Identifying the location and nature of lesions can guide image selection for diagnosis of diplopia. It is helpful for early treatment and prognosis.

Migratory necrolytic erythema as a manifestation of pancreatic neuroendocrine tumor. Clinical-radiological evaluation

ResumenEl glucagonoma es un tumor neuroendocrino de muy baja incidencia, se estima 1 caso cada 20 millones de personas por año. Típicamente, se manifiesta con un síndrome clínico que incluye una dermatosis característica denominada eritema necrolítico migratorio (ENM). Presentamos el caso de un varón de 60 años con ENM como presentación inicial de un tumor pancreático y los hallazgos por imágenes del mismo. Resaltamos la importancia de reconocer las características clínicas del ENM y el rol de los diferentes métodos por imágenes para un diagnóstico precoz y correcto manejo de estos tumores pancreáticos.

In vivo assessment of hypertensive nephrosclerosis using ultrasound localization microscopy.

As a typical chronic kidney disease (CKD), hypertensive nephrosclerosis (HN) is a common syndrome of hypertension, characterized by chronic kidney microvascular damage. Early diagnosis of microvascular damage using conventional ultrasound imaging encounters challenges in sensitivity and specificity owing to the inherent diffraction limit. Ultrasound localization microscopy (ULM) has been developed to obtain microvasculature and microvascular hemodynamics within the kidney, and would be a promising tool for the early diagnosis of CKD. In this study, the advantage of quantitative indexes obtained by using ULM (mean arterial blood flow speeds of different segments of interlobular arteries) over indexes obtained using conventional clinical serum (β2-microglobulin, serum urea nitrogen, and creatinine) and urine (24-h urine volume and urine protein) tests and ultrasound Doppler imaging (peak systolic velocity [PSV], end-diastolic velocity [EDV], and resistance index [RI]) and contrast-enhanced ultrasound imaging (CEUS; rise time [RT], peak intensity [IMAX], mean transit time [mTT], and area under the time-intensity curve [AUC]) for early diagnosis of HN were investigated. Examinations were carried out on six spontaneously hypertensive rats (SHR) and five normal Wistar-Kyoto (WKY) rats at the age of 10weeks. The experimental results show that the indicators derived from conventional clinical inspections (serum and urine tests) and ultrasound imaging (PSV, EDV, RI, RT, IMAX, mTT, and AUC) do not show significant difference between hypertensive and healthy rats (p>0.05), while the TTP of the SHR group (28.52 ± 5.52 s) derived from CEUS is significantly higher than that of the WKY group (18.68 ± 7.32 s; p<0.05). The mean blood flow speed in interlobular artery of SHR (12.47 ± 1.06mm/s) derived from ULM is significantly higher than that of WKY rats (10.13 ± 1.17mm/s; p<0.01). The advantages of ULM over conventional clinical inspections and ultrasound imaging methods for early diagnosis of HN were validated. The quantitative results show that ULM can effectively diagnose HN at the early stage by detecting the blood flow speed changes of interlobular arteries. ULM may promise a reliable technique for early diagnosis of HN in the future.

COVID-19 Pneumonia: The Great Ultrasonography Mimicker.

The pandemic spread of the new severe acute respiratory syndrome coronavirus 2 has raised the necessity to identify an appropriate imaging method for early diagnosis of coronavirus disease 2019 (COVID-19). Chest computed tomography (CT) has been regarded as the mainstay of imaging evaluation for pulmonary involvement in the early phase of the pandemic. However, due to the poor specificity of the radiological pattern and the disruption of radiology centers' functionality linked to an excessive demand for exams, the American College of Radiology has advised against CT use for screening purposes. Lung ultrasound (LUS) is a point-of-care imaging tool that is quickly available and easy to disinfect. These advantages have determined a “pandemic” increase of its use for early detection of COVID-19 pneumonia in emergency departments. However, LUS findings in COVID-19 patients are even less specific than those detectable on CT scans. The scope of this perspective article is to discuss the great number of diseases and pathologic conditions that may mimic COVID-19 pneumonia on LUS examination.

Entropy and uniformity as additional parameters to optimize the effectiveness of bone CT in the evaluation of acromegalic patients.

Acromegaly is considered an important cause of secondary osteoporosis. However, studies on bone mineral density (BMD) have yielded conflicting results and there are few studies that evaluate an accurate imaging method for early diagnosis of osteoporosis in these patients. The objective of this study was to assess whether entropy and uniformity on computed tomography (CT) scans are useful parameters for optimization of assessment of bone fragility in patients with acromegaly. We included 34 patients and 36 controls matched for age and sex in a cross-sectional study. Patients and controls underwent CT scan of the lumbosacral spine, dual-energy x-ray absorptiometry (DXA) and blood tests. A software was developed to calculate the entropy and uniformity by a region of interest (ROI) of the trabecular bone of the first lumbar vertebra (L1). The acromegalic group presented higher mean bone entropy (6.87 ± 0.98 vs. 6.03 ± 1.68, p = 0.013) and lower mean bone uniformity (0.035 ± 0.704 vs. 0.113 ± 0.205, p = 0.035) than control group. Analyzing only acromegalics, mean bone entropy was higher and bone uniformity was lower in patients with hypogonadism than patients without hypogonadism (7.28 ± 0.36 vs. 6.74 ± 1.08, p = 0.038 and 0.008 ± 0.002 vs. 0.043 ± 0.079, p = 0.031) respectively. Patients with acromegaly presented higher BMD and Z-score in the femoral neck than control group (1.156 ± 0.108 vs. 0.925 ± 0.326 g/cm2, p = 0.043 and 0.6 ± 0.6 vs. -0.05 ± 0.8, p = 0.041, respectively). Entropy was negatively correlated with T-score of the lumbar spine (rp = -0.357, p = 0.033) in control group and uniformity was positively correlated with T-score of the lumbar spine, neck, and total hip, respectively (rp = 0.371, p = 0.031; rp = 0.348, p = 0.043 and rp = 0.341, p = 0.049) in acromegalic group. The study identified that entropy and uniformity are a relevant parameters data in bone fragility assessment in acromegalic patients.

Viscoelasticity measurement of ex vivo bovine cartilage using Lamb wave method

Cartilage viscoelasticity changes with cartilage degeneration. Therefore, measurement of cartilage viscoelasticity could offer an alternative to traditional imaging methods for early diagnosis of osteoarthritis. In previous studies, we confirmed the feasibility of using the Lamb wave method (LWM) to assess the elasticity within a simulated cartilage–bone structures. The objective of the present study was to test the suitability of the LWM for measuring viscoelastic properties of ex vivo bovine tibial plateau cartilage. Theoretical and numerical analyses were performed to understand the viscoelastic Lamb wave propagation in cartilage and a suitable measurement range and loading frequency for the LWM were determined. The viscoelasticity of bovine cartilage was experimentally estimated to be 32.8 ± 0.50, 30.9 ± 0.50, and 31.9 ± 1.85 Pa · s for cartilage samples with thicknesses of 2.84 ± 0.02, 2.32 ± 0.03, and 2.01 ± 0.08 mm, respectively, which showed good repeatability during LWM measurements. However, cartilage elasticity was not sensitive to the viscoelastic Lamb wave speed. Indentation tests were also performed and cartilage elasticities were 0.88 ± 0.09, 1.03 ± 0.12, and 0.93 ± 0.09 MPa, respectively. This study validates the use of the LWM for measuring the viscoelasticity of ex vivo cartilage and provides a critical step toward the ultimate goal of measuring the viscoelasticity of cartilage in vivo.

Progression of Post-Traumatic Osteoarthritis in rat meniscectomy models: Comprehensive monitoring using MRI

Knee injury often triggers post-traumatic osteoarthritis (PTOA) that affects articular cartilage (AC), subchondral bone, meniscus and the synovial membrane. The available treatments for PTOA are largely ineffective due to late diagnosis past the “treatment window”. This study aimed to develop a detailed understanding of the time line of the progression of PTOA in murine models through longitudinal observation of the femorotibial joint from the onset of the disease to the advanced stage. Quantitative magnetic resonance microimaging (µMRI) and histology were used to evaluate PTOA-associated changes in the knee joints of rats subjected to knee meniscectomy. Systematic longitudinal changes in the articular cartilage thickness, cartilage T2 and the T2 of epiphysis within medial condyles of the tibia were all found to be associated with the development of PTOA in the animals. The following pathogenesis cascade was found to precede advanced PTOA: meniscal injury → AC swelling → subchondral bone remodelling → proteoglycan depletion → free water influx → cartilage erosion. Importantly, the imaging protocol used was entirely MRI-based. This protocol is potentially suitable for whole-knee longitudinal, non-invasive assessment of the development of OA. The results of this work will inform the improvement of the imaging methods for early diagnosis of PTOA.

Applicability of active infrared thermography for screening of human breast: a numerical study.

Active infrared thermography is a fast, painless, noncontact, and noninvasive imaging method, complementary to mammography, ultrasound, and magnetic resonance imaging methods for early diagnosis of breast cancer. This technique plays an important role in early detection of breast cancer to women of all ages, including pregnant or nursing women, with different sizes of breast, irrespective of either fatty or dense breast. This proposed complementary technique makes use of infrared emission emanating from the breast. Emanating radiations from the surface of the breast under test are detected with an infrared camera to map the thermal gradients over it, in order to reveal hidden tumors inside it. One of the reliable active infrared thermographic technique, linear frequency modulated thermal wave imaging is adopted to detect tumors present inside the breast. Further, phase and amplitude images are constructed using frequency and time-domain data analysis schemes. Obtained results show the potential of the proposed technique for early diagnosis of breast cancer in fatty as well as dense breasts.

A Novel Method to Detect Interface of Conductivity Changes in Magneto-Acousto-Electrical Tomography Using Chirp Signal Excitation Method

As a non-invasive and hybrid imaging modality, magneto-acoustic-electrical tomography (MAET) is extremely useful for the electrical conductivity measurement in vivo. Based on the Verasonics system and the MC600 displacement platform, we designed and implemented a novel MAET system with a chirp pulse stimulation (MAET-CPS) method for electrical conductivity measurement. In the system, a 2–3 MHz chirp signal was exploited for stimulating ultrasound power probe. Then, the interface positions of conductivity variation were obtained by digital demodulation of the excitation signal and the received voltage signal. Finally, five different homogeneous phantoms with same size were used to investigate the feasibility, accuracy, and repeatability of MAET-CPS. The results showed that: 1) when a chirp signal with pulse duration of $1000~\mu \text{s}$ was used to stimulate a homogeneous phantom with 0.5% NaCl, the reconstructed B-scan image of the conductivity distribution was highly consistent with the ultrasound B-scan imaging and physical size; 2) the signal-to-noise ratio of the system and the detection resolution of the interface of conductivity variations could be influenced by the linear frequency modulation period. The resolution obtained by using chirp signal with pulse duration of $1000~\mu \text{s}$ was better than that of $500~\mu \text{s}$ and $1500~\mu \text{s}$ ; and 3) the interfaces of conductivity variations of homogeneous phantoms with five different concentrations (0.4%, 0.5%, 0.6%, 0.7%, and 0.8%) were clearly presented and the measured thicknesses of each phantom showed good agreement with the thickness of the target sample. This paper has laid the foundation for the MAET-CPS modality in the phantom sample, and MAET-CPS is expected to become an alternative imaging method for early diagnosis and detection of biological cancerous tissues.

Advances in imaging methods for early diagnosis of rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disease with unknown etiology.The main feature of RA is chronic,symmetrical and invasive arthritis.RA may present with severe joint deformity and functional loss,which has higher disability and fatality rates.At present,no effective measures can reverse bone damage associated with RA clinically.Therefore,early diagnosis of RA is critical to improve prognosis.In recent years,imaging increasingly plays an important role in the early diagnosis of RA.This article reviews recent advances in imaging methods for early diagnosis of RA. Key words: Arthritis, rheumatoid ; Diagnostic imaging; Trends

Development of positron emission tomography imaging by 64Cu-labeled Fab for detecting ERC/mesothelin in a mesothelioma mouse model

Malignant mesothelioma is a highly aggressive form of cancer. Curative surgery is the only effective therapy for mesothelioma, and therefore early diagnosis is important. However, early diagnosis is difficult using current diagnostic imaging techniques, and a new imaging method for early diagnosis is urgently required. We evaluated the affinity of radiolabeled monoclonal antibodies to the C-terminal fragment of ERC/mesothelin for this purpose. In-labeled or I-labeled IgG against C-terminal fragment of ERC and its Fab fragment were evaluated in vitro by cell binding, competitive inhibition, and cellular internalization assays, and in vivo by biodistribution in mice bearing ERC-expressing tumors. Next, the Fab fragment was labeled with the positron emitter Cu and evaluated by positron emission tomography (PET). Radiolabeled IgG and Fab showed specific binding to ERC-expressing mesothelioma cells with high affinity. Both radiolabeled IgG and Fab internalized into cells after binding to ERC on the cell surface. In-labeled IgG accumulated in ERC-expressing tumors and resulted in a moderate tumor-to-blood ratio at 4 days after injection. Furthermore, PET using Cu-labeled Fab visualized the tumor at 6 h after injection. Cu-labeled Fab can be useful for ERC-specific PET imaging, and can thus facilitate improved diagnosis of patients with early-stage mesothelioma.

Advances in molecular imaging of pancreatic beta cells.

The development of non-invasive imaging methods for early diagnosis of beta cell associated metabolic diseases, including type 1 and type 2 diabetes (T1D and T2D), has recently drawn interest from the molecular imaging community and clinical investigators. Due to the challenges imposed by the location of the pancreas, the sparsely dispersed beta cell population within the pancreas, and the poor understanding of the pathogenesis of the diseases, clinical diagnosis of beta cell abnormalities is still limited. Current diagnostic methods are invasive, often inaccurate, and usually performed post-onset of the disease. Advances in imaging techniques for probing beta cell mass and function are needed to address this critical health care problem. A variety of imaging techniques have been tested for the assessment of pancreatic beta cell islets. Here we discuss current advances in magnetic resonance imaging (MRI), bioluminescence imaging (BLI), and nuclear imaging for the study of beta cell diseases. Spurred by early successes in nuclear imaging techniques for beta cells, especially positron emission tomography (PET), the need for beta cell specific ligands has expanded. Progress for obtaining such ligands is presented. We report our preliminary efforts of developing such a peptidic ligand for PET imaging of pancreatic beta cells.

Postoperative Diagnosis of Aorto-Right Ventricular Outflow Tract Fistula Caused by Stab Wound: A Case Report

Traumatic aorto-right ventricular fistulas are rare lesions after penetrating thoracic injuries. Although aorto-right ventricular fistulas are well tolerated initially, most of them result in heart failure over a variable period. Penetrating cardiac trauma cases often need prompt cardiac surgery that does not allow further and detailed imaging methods for early diagnosis of lesions such as intracardiac defects and intracardiac fistulas. In this article, we report a case of aorto-right ventricular outflow tract fistula after a stab wound that was diagnosed on the second day after first successful surgery for acute tamponade.