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1.
Biomed Eng Lett ; 14(3): 571-582, 2024 May.
Article En | MEDLINE | ID: mdl-38645597

Intracardiac echocardiography (ICE) enables cardiac imaging with a wide field of view, deep imaging depth, and high frame rate during surgery. However, strong sidelobe and grating lobe artifacts created by the ultra-compact transducer degrade its image quality, making diagnosis and monitoring of treatment difficult. Conventionally, aperture apodization algorithms are often used to suppress sidelobe and grating lobe artifacts at the expense of lateral resolution, which is undesirable in ICE. In this study, we present comparative results of the beamforming methods specifically in ICE application. We demonstrate and compare five nonlinear beamforming algorithms in ICE: nonlinear pth root delay and sum (NL-p-DAS), nonlinear pth root spectral magnitude scaling (NL-p-SMS), delay-and-sum with coherence factors (DAS + SCF), delay and sum with apodization (DAS + apodization) and delay and sum (DAS). Phantom and ex-vivo experiment compare the performance of each algorithm in static and dynamic conditions. DAS + SCF shows the best lateral resolution, and all four algorithms improve the image contrast and sidelobe suppression over conventional DAS. NL-p-SMS stands out for the best axial resolution and suppression of grating lobe artifacts. For motion tracking, NL-p-SMS shows better temporal resolution than other methods. Overall, all the beamforming algorithms other than DAS showed improved image quality. Among them, NL-p-SMS, which has a high temporal resolution, showed the potential for providing more accurate information regards movement tracking. Supplementary Information: The online version contains supplementary material available at 10.1007/s13534-024-00352-9.

2.
Methodist Debakey Cardiovasc J ; 20(2): 70-80, 2024.
Article En | MEDLINE | ID: mdl-38495664

Pulmonary arterial hypertension (PAH) is a rare devastating disease characterized by elevated pulmonary artery pressure and increased pulmonary vascular resistance. Females have a higher incidence of PAH, which is reflected globally across registries in the United States, Europe, and Asia. However, despite female predominance, women had better outcomes compared with male patients, a finding that has been labeled the "estrogen paradox." Special considerations should be given to women with PAH regarding sexual health, contraception, family planning, and treatment before, during, and after pregnancy. Pregnant women with PAH should be referred to a pulmonary hypertension care center; a multidisciplinary team approach is recommended, and Cesarean section is the preferred mode of delivery. While pregnancy outcomes have improved over the years with PAH-specific therapy, pregnancy portends a high-risk for those with PAH. Continued research is needed to tailor PAH treatment for women.


Hypertension, Pulmonary , Hypertension , Female , Pregnancy , Humans , Male , Hypertension, Pulmonary/diagnosis , Hypertension, Pulmonary/epidemiology , Hypertension, Pulmonary/therapy , Cesarean Section/adverse effects , Pregnancy Outcome , Familial Primary Pulmonary Hypertension/complications
3.
Photoacoustics ; 31: 100510, 2023 Jun.
Article En | MEDLINE | ID: mdl-37228578

Photoacoustic imaging (PAI) has emerged as a molecular-selective imaging technology based on optical absorption contrast. Dichroism-sensitive photoacoustic (DS-PA) imaging has been reported, where the absorption coefficient has a vector characteristic, featuring dimensions of contrast in polarization and wavelength. Herein, we present a DS-PA microscopy (DS-PAM) system that implements optical anisotropy contrast and molecular selectivity. Moreover, we propose mathematical solutions to fully derive dichroic properties. A wavelength for the PAI of collagenous tissue was used, and the proposed algorithms were validated using linear dichroic materials. We successfully mapped dichroic information in fibrous tissue imaging based on the degree of anisotropy and axis orientation, and also deduced mechanical assessment from the tissue arrangement. The proposed DS-PAM system and algorithms have great potential in various diagnostic fields using polarimetry, such as musculoskeletal and cardiovascular systems.

4.
J Biomed Opt ; 28(8): 082805, 2023 08.
Article En | MEDLINE | ID: mdl-36844430

Significance: Corticosteroids-commonly prescribed medications for skin diseases-inhibit the secretion of vasodilators, such as prostaglandin, thereby exerting anti-inflammatory action by constricting capillaries in the dermis. The effectiveness of corticosteroids is determined by the degree of vasoconstriction followed by skin whitening, namely, the blanching effect. However, the current method of observing the blanching effect indirectly evaluates the effects of corticosteroids. Aim: In this study, we employed optical-resolution photoacoustic (PA) microscopy (OR-PAM) to directly visualize the blood vessels and quantitatively evaluate vasoconstriction. Approach: Using OR-PAM, the vascular density in mice skin was monitored for 60 min after performing each experimental procedure for four groups, and the vasoconstriction was quantified. Volumetric PA data were segmented into the papillary dermis, reticular dermis, and hypodermis based on the vascular characteristics obtained through OR-PAM. The vasoconstrictive effect of each skin layer was quantified according to the dermatological treatment method. Results: In the case of corticosteroid topical application, vasoconstriction was observed in the papillary ( 56.4 ± 10.9 % ) and reticular ( 45.1 ± 4.71 % ) dermis. For corticosteroid subcutaneous injection, constriction was observed solely in the reticular ( 49.5 ± 9.35 % ) dermis. In contrast, no vasoconstrictions were observed with nonsteroidal topical application. Conclusions: Our results indicate that OR-PAM can quantitatively monitor the vasoconstriction induced by corticosteroids, thereby validating OR-PAMs potential as a practical evaluation tool for predicting the effectiveness of corticosteroids in dermatology.


Anti-Inflammatory Agents , Photoacoustic Techniques , Animals , Mice , Anti-Inflammatory Agents/pharmacology , Skin/blood supply , Adrenal Cortex Hormones/pharmacology , Vasoconstriction , Spectrum Analysis , Photoacoustic Techniques/methods
5.
Sci Rep ; 12(1): 18093, 2022 10 27.
Article En | MEDLINE | ID: mdl-36302839

This study aims to measure the monetary value of health asset based on the self-reported health status and rate of health asset value (HAV), and to evaluate its application to the subjective well-being and health competency of a representative sample of South Korea. From March to April 2021, 1000 participants were randomly sampled nationwide in South Korea and administered questionnaires including self-reported rate of health asset value and health status, the Subjective Well-Being Index (SWBI), Patient Health Questionnaire-9 (PHQ-9), Smart Management Strategy for Health Assessment Tool (SAT), and 11 health habits. In multiple stepwise logistic regression model adjusted for basic demographic variables (age, sex, region, monthly income level, and comorbidity), current HAV was independently associated positively with SWBI (adjusted odds ratio [aOR], 4.32; confidence interval [CI] 2.27-8.23) and negatively with PHQ-9 (aOR 0.68; 95% CI 0.51-0.90). Core (aOR 1.66; CI 1.25-2.19), Preparation (aOR 1.79; CI 1.24-2.59), and Implementation Strategy scores of SAT (aOR 1.79; CI 1.26-2.55) were independently associated positively with current HAV. All 11 health habits were independently associated positively with current HAV (aOR range from 1.80 to 3.19). The HAV approach offers a new monetary value of health that can be used in making individual or political decisions of improving health or reducing health inequity.


Depression , Health Status , Humans , Depression/epidemiology , Republic of Korea/epidemiology , Self Report , Habits
6.
JACC Case Rep ; 4(16): 1060-1064, 2022 Aug 17.
Article En | MEDLINE | ID: mdl-36062058

We present a case of extensive coronary atherosclerotic disease in a younger patient with an anomalous left coronary artery with transseptal course and show the utility of multimodality evaluation to determine the culprit lesion in patients presenting with this rare association. (Level of Difficulty: Intermediate.).

7.
J Biophotonics ; 15(11): e202200065, 2022 11.
Article En | MEDLINE | ID: mdl-35766447

Histological analysis is widely used to evaluate injured tendons; however, it has the limitation of being semi-quantitative. Hence, we developed a quantification method to objectively evaluate the fibrous structure of tendons, exhibiting the optical property of birefringence, using polarization-sensitive optical coherence tomography (PS-OCT). We used a partial-rupture rat model in which the middle 0.75 cm of the Achilles tendon was cut with a blade. Rats were sacrificed at 2, 4 or 6 weeks after the injury, and PS-OCT and histological analyzes were performed. The PS-OCT phase retardation images and score well represented the structural changes of the injured tendon according to the wound healing state. Therefore, the proposed novel quantification method using PS-OCT can be used to evaluate the fibrous structural status of tendons.


Achilles Tendon , Tomography, Optical Coherence , Rats , Animals , Birefringence , Tomography, Optical Coherence/methods , Achilles Tendon/diagnostic imaging , Wound Healing
8.
Eur Heart J Case Rep ; 6(1): ytac021, 2022 Jan.
Article En | MEDLINE | ID: mdl-35106445

BACKGROUND: Eosinophilic granulomatosis with polyangiitis (EGPA) is a multisystem disorder commonly affecting the lung and skin, with cardiovascular involvement found in up to 60% of patients. We present a case of myocardial infarction with non-obstructive coronary arteries (MINOCA) as the initial presentation of EGPA. CASE SUMMARY: A 52-year-old female with past medical history of asthma, recurrent sinusitis, and peripheral neuropathy presented to our hospital with chest pain, rash, acute vision loss, elevated troponin, and peripheral eosinophilia. Electrocardiogram showed no ischaemic changes and coronary angiography displayed normal coronary anatomy. On a subsequent visit, cardiac magnetic resonance (CMR) showed predominant focal anteroseptal and inferoseptal akinesis with focal sub-endocardial delayed enhancement, indicative of a myocardial infarction involving the septal branches of the left anterior descending artery. Due to the focal findings on CMR, peripheral eosinophilia, and rash, the patient was evaluated for EGPA. Rheumatologic workup and skin biopsy were suggestive of small vessel vasculitis. The patient was diagnosed with multi-organ EGPA, involving the coronaries, which was ultimately thought to be the aetiology of her MINOCA. Following steroid and monoclonal antibody therapy, the patient experienced notable improvement in her cardiac function at follow-up appointments. DISCUSSION: This is a unique case MINOCA as the initial presentation of EGPA. Considering the heterogeneous disease presentation of those diagnosed with MINOCA, utilization of CMR is essential to guide diagnosis and management of such patients.

9.
Sci Rep ; 11(1): 16636, 2021 08 17.
Article En | MEDLINE | ID: mdl-34404853

Swept-source optical coherence tomography (SS-OCT) is an attractive high-speed imaging technique for retinal angiography. However, conventional swept lasers vary the cavity length of the laser mechanically to tune the output wavelength. This causes sweep-timing jitter and hence low phase stability in OCT angiography. Here, we improve an earlier phase-stabilized, akinetic, SS-OCT angiography (OCTA) method by introducing coherent averaging. We develop an active mode-locking (AML) laser as a high phase-stable akinetic swept source for the OCTA system. The phase stability of the improved system was analyzed, and the effects of coherent averaging were validated using a retina phantom. The effectiveness of the coherent averaging method was further confirmed by comparing coherently and conventionally averaged en face images of human retinal vasculature for their contrast-to-noise ratio, signal-to-noise ratio, and vasculature connectivity. The contrast-to-noise ratio was approximately 1.3 times larger when applying the coherent averaging method in the human retinal experiment. Our coherent averaging method with the high phase-stability AML laser source for OCTA provides a valuable tool for studying healthy and diseased retinas.


Contrast Media , Fluorescein Angiography/methods , Retinal Vessels/diagnostic imaging , Tomography, Optical Coherence/methods , Humans , Phantoms, Imaging , Reproducibility of Results
10.
J Pers Med ; 11(5)2021 May 03.
Article En | MEDLINE | ID: mdl-34063666

This study aimed to assess and compare the ultrasonographic (US) pathologic findings in patients with polymyalgia rheumatica (PMR) and bilateral frozen shoulder (FS). We included 19 patients with clinically diagnosed PMR and 19 patients with stage II bilateral FS. The US evaluation included the assessment of subacromial-subdeltoid (SASD) bursitis, long head of biceps (LHB) tenosynovitis, and posterior and inferior glenohumeral (GH) synovitis. Unilateral SASD bursitis was noted significantly more frequently in PMR patients than in bilateral FS patients (p = 0.001). There were no significant differences in the incidence of unilateral LHB tenosynovitis and posterior GH synovitis between PMR and bilateral FS patients (p = 0.108 and p = 0.304, respectively). Unilateral inferior GH synovitis was more common among bilateral FS patients than among PMR patients (p < 0.001). Bilateral SASD bursitis and LHB tenosynovitis were noted significantly more frequently in PMR patients than in bilateral FS patients (p < 0.001 and 0.049, respectively). Significant differences were not observed in the incidence of bilateral posterior GH synovitis between PMR and bilateral FS patients (p = 0.426). Bilateral inferior GH synovitis was more common among bilateral FS patients than among PMR patients (p = 0.044). The US evidence for bilateral inferior GH synovitis without bilateral SASD showed high specificity (94.7%) with sensitivity (78.9%) for the diagnosis of bilateral FS. SASD bursitis, representing periarticular synovial inflammation, was more common among the patients with PMR than among the patients with bilateral FS. Inferior GH synovitis without SASD bursitis suggests FS rather than PMR in patients with bilateral shoulder pain.

11.
Children (Basel) ; 8(5)2021 May 11.
Article En | MEDLINE | ID: mdl-34064562

Duchenne muscular dystrophy is a progressive and lethal X-linked recessive neuromuscular disease caused by mutations in the dystrophin gene. It has a high rate of diagnostic delay; early diagnosis and treatment are often not possible due to delayed recognition of muscle weakness and lack of effective treatments. Current treatments based on genetic therapy can improve clinical results, but treatment must begin as early as possible before significant muscle damage. Therefore, early diagnosis and rehabilitation of Duchenne muscular dystrophy are needed before symptom aggravation. Creatine kinase is a diagnostic marker of neuromuscular disorders. Herein, the authors report a case of an infant patient with Duchenne muscular dystrophy with a highly elevated creatine kinase level but no obvious symptoms of muscle weakness. The patient was diagnosed with Duchenne muscular dystrophy via next-generation sequencing and chromosomal microarray analysis to identify possible inherited metabolic and neuromuscular diseases related to profound hyperCKemia. The patient is enrolled in a rehabilitation program and awaits the approval of the genetic treatment in Korea. This is the first report of an infantile presymptomatic Duchenne muscular dystrophy diagnosis using next-generation sequencing and chromosomal microarray analysis.

12.
Sensors (Basel) ; 21(4)2021 Feb 23.
Article En | MEDLINE | ID: mdl-33672147

In this study, two-photon laser scanning microscopy (TPLSM) based on the internet of things (IoT) is proposed as a remote research equipment sharing system, which enables the remote sharing economy. IoT modules, where data are transmitted to and received from the remote users in the web service via IoT, instead of a data acquisition (DAQ) system embedded in the conventional TPLSM, are installed in the IoT-based TPLSM (IoT-TPLSM). The performance for each IoT module is evaluated independently, and it is confirmed that it works well even in a personal computer-free environment. In addition, a message queuing telemetry transport (MQTT) protocol is applied to the DAQ interface in the web service, and a graphic user interface for enabling the remote users to operate IoT-TPLSM remotely is also designed and implemented. For the image acquisition demonstration, the stained cellular images and the autofluorescent tissue images are obtained in IoT-TPLSM. Lastly, it is confirmed that the comparable performance is provided with the conventional TPLSM by evaluating the imaging conditions and qualities of the three-dimensional image stacks processed in IoT-TPLSM.

13.
J Biomed Opt ; 25(5): 1-8, 2020 05.
Article En | MEDLINE | ID: mdl-32406216

SIGNIFICANCE: Collagen is a basic component of many tissues such as tendons, muscles, and skin, and its imaging helps diagnose and monitor treatments in a variety of fields, including orthopedics. However, due to the overlapping peaks of the absorption spectrum with water in the short-wave infrared region (SWIR), it is difficult to select an optimal wavelength and obtain the photoacoustic (PA) image for collagen-based tissues. Therefore, an additional approach to selecting the proper wavelength is needed. AIM: The aim of this study is to derive an effective PA absorption spectrum of collagen to select the optimal wavelength for high-sensitive PA imaging (PAI). APPROACH: We measure the absorption spectrum by acquiring the PA signal from various collagen-based samples. To derive an effective PA absorption spectrum in the SWIR band, the following two parameters should be considered: (1) the laser excitation for generating the PA signal and (2) the absorption spectrum for water in the SWIR band. This molecular intrinsic property suggests the optimal wavelength for high-sensitive PAI of collagen-based samples. RESULTS: PA absorption spectral peaks of collagen were found at wavelengths of 1200, 1550, and 1700 nm. Thereby, the PA signal increased by up to five times compared with the wavelength commonly used in collagen PAI. We applied a pulsed fiber laser with a center wavelength of 1560 nm, and the three-dimensional PA image of a collagen patch was obtained. CONCLUSIONS: The effective PA absorption spectrum contributes to the improvement of the PA image sensitivity by presenting the optimal wavelength of the target samples.


Photoacoustic Techniques , Collagen , Imaging, Three-Dimensional , Lasers , Spectrum Analysis
14.
Environ Mol Mutagen ; 57(7): 526-34, 2016 08.
Article En | MEDLINE | ID: mdl-27452341

Antiretroviral (ARV) drug therapy, given during pregnancy for prevention of mother-to-child transmission of human immunodeficiency virus 1 (HIV-1), induces fetal mitochondrial dysfunction in some children. However, the persistence/reversibility of that dysfunction is unclear. Here we have followed Erythrocebus patas (patas) monkey offspring for up to 3 years of age (similar in development to a 15-year old human) after exposure of the dams to human-equivalent in utero ARV exposure protocols. Pregnant patas dams (3-5/exposure group) were given ARV drug combinations that included zidovudine (AZT)/lamivudine (3TC)/abacavir (ABC), or AZT/3TC/nevirapine (NVP), for the last 10 weeks (50%) of gestation. Infants kept for 1 and 3 years also received drug for the first 6 weeks of life. In offpsring at birth, 1 and 3 years of age mitochondrial morphology, examined by electron microscopy (EM), was compromised compared to the unexposed controls. Mitochondrial DNA (mtDNA), measured by hybrid capture chemiluminescence assay (HCCA) was depleted in hearts of patas exposed to AZT/3TC/NVP at all ages (P < 0.05), but not in those exposed to AZT/3TC/ABC at any age. Compared to unexposed controls, mitochondrial reserve capacity oxygen consumption rate (OCR by Seahorse) in cultured bone marrow mesenchymal fibroblasts from 3-year-old patas offspring was ∼50% reduced in AZT/3TC/ABC-exposed patas (P < 0.01), but not in AZT/3TC/NVP-exposed patas. Overall the data show that 3-year-old patas sustain persistent mitochondrial dysfunction as a result of perinatal ARV drug exposure. Environ. Mol. Mutagen. 57:526-534, 2016. © 2016 Wiley Periodicals, Inc.


Anti-HIV Agents/toxicity , DNA, Mitochondrial/analysis , Mitochondria/drug effects , Prenatal Exposure Delayed Effects/chemically induced , Animals , Anti-HIV Agents/administration & dosage , Bone Marrow Cells/drug effects , Bone Marrow Cells/metabolism , Brain/drug effects , Brain/growth & development , Brain/pathology , DNA, Mitochondrial/genetics , Dideoxynucleosides/administration & dosage , Dideoxynucleosides/toxicity , Drug Therapy, Combination , Erythrocebus patas , Female , Gestational Age , Heart/drug effects , Heart/growth & development , Lamivudine/administration & dosage , Lamivudine/toxicity , Mitochondria/genetics , Mitochondria/ultrastructure , Mitochondria, Heart/drug effects , Mitochondria, Heart/genetics , Mitochondria, Heart/ultrastructure , Oxygen Consumption/drug effects , Pregnancy , Prenatal Exposure Delayed Effects/genetics , Prenatal Exposure Delayed Effects/pathology , Zidovudine/administration & dosage , Zidovudine/toxicity
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