Browsing by Subject "ULTRASOUND"

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  • Niemelä, Tytti; Viren, Tuomas; Liukkonen, Jukka; Argüelles, David; te Moller, Nikae C. R.; Puhakka, Pia H.; Jurvelin, Jukka S.; Tulamo, Riitta-Mari; Töyräs, Juha (2014)
  • Song, Xiaojun; Moilanen, Petro; Zhao, Zuomin; Ta, Dean; Pirhonen, Jalmari; Salmi, Ari; Haeggström, Edward; Myllyla, Risto; Timonen, Jussi; Wang, Weiqi (2016)
    The fundamental flexural guided wave (FFGW) permits ultrasonic assessment of the wall thickness of solid waveguides, such as tubes or, e.g., long cortical bones. Recently, an optical non-contact method was proposed for ultrasound excitation and detection with the aim of facilitating the FFGW reception by suppressing the interfering modes from the soft coating. This technique suffers from low SNR and requires iterative physical scanning across the source-receiver distance for 2D-FFT analysis. This means that SNR improvement achieved by temporal averaging becomes time-consuming (several minutes) which reduces the applicability of the technique, especially in time-critical applications such as clinical quantitative ultrasound. To achieve sufficient SNR faster, an ultrasonic excitation by a base-sequence-modulated Golay code (BSGC, 64-bit code pair) on coated tube samples (1-5 mm wall thickness and 5 mm soft coating layer) was used. This approach improved SNR by 21 dB and speeded up the measurement by a factor of 100 compared to using a classical pulse excitation with temporal averaging. The measurement now took seconds instead of minutes, while the ability to determine the wall thickness of the phantoms was maintained. The technique thus allows rapid noncontacting assessment of the wall thickness in coated solid tubes, such as the human bone. (C) 2016 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
  • Pérez, Alejandro Garcia; Nieminen, Heikki J.; Finnilä, Mikko; Salmi, Ari; Pritzker, Kenneth P. H.; Lampsijärvi, Eetu; Paulin, Tor; Airaksinen, Anu J.; Saarakkala, Simo; Haeggström, Edward (2018)
    Localized delivery of drugs into articular cartilage (AC) may facilitate the development of novel therapies to treat osteoarthritis (OA). We investigated the potential of spark-gap-generated sound to deliver a drug surrogate, i.e., methylene blue (MB), into AC. In vitro experiments exposed bovine AC samples to either simultaneous sonication and immersion in MB (Treatment 1; n = 10), immersion in MB after sonication (Control 1; n = 10), solely immersion in MB (Control 2; n = 10), or neither sonication nor immersion in MB (Control 3; n = 10). The sonication protocol consisted of 1,000 spark-gap -generated pulses. Delivery of MB into AC was estimated from optical absorbance in transmission light microscopy. Optical absorbance was significantly greater in the treatment group up to 900 mu m depth from AC surface as compared to all controls. Field emission scanning electron microscopy (FESEM), histological analysis, and digital densitometry (DD) of sonicated (n = 6) and non-sonicated (n = 6) samples showed no evidence of sonication-induced changes in proteoglycan content or collagen structure. Consequently, spark-gap -generated sound may offer a solution for localized drug delivery into AC in a non-destructive fashion. Further research on this method may contribute to OA drug therapies.
  • CLOTBUST-ER Trial Investigators; Alexandrov, Andrei V.; Tsivgoulis, Georgios; Köhrmann, Martin; Soinne, Lauri; Schellinger, Peter D. (2019)
    Background: Results of our recently published phase III randomized clinical trial of ultrasound-enhanced thrombolysis (sonothrombolysis) using an operator-independent, high frequency ultrasound device revealed heterogeneity of patient recruitment among centers. Methods: We performed a post hoc analysis after excluding subjects that were recruited at centers reporting a decline in the balance of randomization between sonothrombolysis and concurrent endovascular trials. Results: From a total of 676 participants randomized in the CLOTBUST-ER trial we identified 52 patients from 7 centers with perceived equipoise shift in favor of endovascular treatment. Post hoc sensitivity analysis in the intention-to-treat population adjusted for age, National Institutes of Health Scale score at baseline, time from stroke onset to tPA bolus and baseline serum glucose showed a significant (p <0.01) interaction of perceived endovascular equipoise shift on the association between sonothrombolysis and 3 month functional outcome [adjusted common odds ratio (cOR) in centers with perceived endovascular equipoise shift: 0.22, 95% CI 0.06-0.75; p = 0.02; adjusted cOR for centers without endovascular equipoise shift: 1.20, 95% CI 0.89-1.62; p = 0.24)]. After excluding centers with perceived endovascular equipoise shift, patients randomized to sonothrombolysis had higher odds of 3 month functional independence (mRS scores 0-2) compared with patients treated with tPA only (adjusted OR: 1.53; 95% CI 1.01-2.31; p = 0.04). Conclusion: Our experience in CLOTBUST-ER indicates that increasing implementation of endovascular therapies across major academic stroke centers raises significant challenges for clinical trials aiming to test noninterventional or adjuvant reperfusion strategies.
  • FIGO Placenta Accreta Diag & Mana; Jauniaux, Eric; Bhide, Amar; Kennedy, Anne; Woodward, Paula; Hubinont, Corrine; Collins, Sally; Tikkanen, Minna (2018)
  • Pohjoranta, Elina; Suhonen, Satu; Mentula, Maarit; Heikinheimo, Oskari (2017)
    Objective: To assess the success and factors affecting early intrauterine device (IUD) provision after first trimester medical termination of pregnancy (MTOP). Study design: Subgroup analysis of a randomized contraceptive trial assessing the long-term effects of early provision of intrauterine contraception following abortion. Altogether, 606 women undergoing MTOP were included and followed for 3 months. The intervention group (n=307) was offered an IUD (either the levonorgestrel-releasing intrauterine system or copper-IUD) at a follow-up visit 1-4 weeks after MTOP. The control group (n=299) contacted primary health care for follow-up and contraceptive provision. Adverse events (infections, bleeding, residual tissue and incomplete abortion) were analyzed on intention-to-treat basis and IUD expulsions on per-protocol (PP) basis. Results: In the intervention group, 234 women (76.2%) received the IUD as scheduled, 46 later (altogether 91.2%). In the control group, the corresponding figures were 8 (2.7%) and 64 [altogether 24.1%, Odds ratio (OR) (95% Confidence interval (Cl)) = 32.7 (20.3-52.6)]. Eighty-five (27.7%) women in the intervention group and 38 (12.7%) in the control group received treatment (administration of antibiotics, misoprostol or surgical evacuation) because of presumed adverse event [2.63 (1.72-4.01)], mainly residual tissue. In the control group, 23 (60.5%) of these occurred during the first 2 weeks. IUD expulsion occurred in 12 (5.4%) of the 222 women in the intervention group (PP basis). Conclusions: When provided as part of abortion service, most early insertions following MTOP were performed as planned. The main reason for postponement was overdiagnosis of adverse events suspected at follow-up. The rate of IUD expulsion was similar to that reported previously. Implications: Early insertion following MTOP is safe, and the rate of IUD expulsion is low. Most adverse events possibly delaying IUD insertion occur early. Based on timing of adverse events in the control group, IUD insertion at approximately 2 weeks after completed MTOP seems optimal. (C) 2017 Elsevier Inc. All rights reserved.
  • Måseide, Ragnhild J.; Berntorp, Erik; Astermark, Jan; Olsson, Anna; Bruzelius, Maria; Frisk, Tony; Nummi, Vuokko; Lassila, Riitta; Tjonnfjord, Geir E.; Holme, Pål A. (2020)
    Introduction The prevalence of arthropathy in moderate haemophilia A (MHA) and B (MHB) is not well known. Aim We evaluated joint health in Nordic patients in relation to their treatment modality. Methods A cross-sectional, multicentre study covering MHA and MHB in Sweden, Finland and Norway. Arthropathy was evaluated by ultrasound (HEAD-US) and Haemophilia Joint Health Score (HJHS). Results We report on 145 patients: median age 28 years (IQR 13-52) and 61% MHA. Baseline factor VIII/factor IX activity (FVIII/FIX:C) was 2 IU/dL (median) (IQR 2-4): lower for MHB (2 IU/dL, IQR 1-2) than MHA (3 IU/dL, IQR 2-4) (P <.01). Eighty-five per cent of MHA and 73% MHB had a history of haemarthrosis (P = .07). Age at first joint bleed was lower for MHA (5 years [median], IQR 3-7) than MHB (7 years, IQR 5-12) (P = .01). Thirty-eight per cent received prophylaxis, started at median 10 years of age (IQR 4-24). Median joint bleeds and serious other bleeds during the last 12 months were both zero (IQR 0-1). Total HEAD-US captured 0/48 points (median) (IQR 0-2) and HJHS 4/120 points (IQR 1-10) with strong correlation between them (r = .72). FVIII/FIX:C
  • Kauffold, Johannes; Peltoniemi, Olli; Wehrend, Axel; Althouse, Gary C. (2019)
    Simply Summary: Real-time ultrasonography (RTU) has become an essential diagnostic value when assessing female swine reproduction in either individual or groups of animals. Diagnostic application of RTU is applied throughout most stages of production, including gilt development, breeding, gestation and farrowing. Along with its most common use in on-farm assessment of pregnancy status, RTU is also used to troubleshoot disruptions in reproductive performance such as delayed puberty, prolonged wean-to-estrus interval, absence of post-weaning estrus, decreased conception and farrowing rates, vulval discharge, peripartum and puerperal disorders. This review aims to provide an overview on principles and clinical uses of RTU in female reproduction on commercial swine farms. Abstract: Within the past 30 years, through ongoing technology and portability developments, real-time (b-mode) ultrasonography (RTU) has increasingly become a valuable diagnostic tool in assessing the female reproductive tract in swine. Initially applied in swine production to visually determine pregnancy status, RTU use has expanded to include assessment of the peri-pubertal and mature non-pregnant females as well. Transabdominal and transrectal modalities to visualizing the reproductive tract in swine have been reported with the transabdominal approach more common due to the fact of its ease of accessibility, animal/personnel safety, and reduced time to perform. Adjustable frequency transducers are preferred as they allow optimization of image quality at various depths. If a single transducer frequency must be selected, a 5 MHz probe provides the best versatility for visualizing the reproductive tract in swine. Other basic requirements for ultrasound equipment which will be used on commercial swine farms include being light weight and easy to handle, readily cleanable and disinfectable, long battery-life, and good durability. When using RTU for pregnancy determination, diagnosis is based upon a combination of the animal's breeding records, the presence of embryonic fluid, and, depending upon gestational stage, fetal structures. If RTU is used as a diagnostic tool in assessing reproductive problems in an individual or a group of animals, sonographic evaluation of both the uterus and ovaries is performed. Tissues are delineated and assessed based upon their echogenicity, echotexture, and size. Uses of RTU in clinical practice may include assessment of delayed puberty, prolonged wean-to-estrus interval, absence of post-weaning estrus, herd disruptions in conception and farrowing rates, vulval discharge, peripartum and puerperal disorders. This review aims to provide an overview on principles and clinical uses of RTU with respect to application to address female reproductive performance issues in commercial swine operations.
  • Ylitalo, Tuomo; Finnilä, Mikko A. J.; Gahunia, Harpal K.; Karhula, Sakari S.; Suhonen, Heikki; Valkealahti, Maarit; Lehenkari, Petri; Haeggström, Edward; Pritzker, Kenneth P. H.; Saarakkala, Simo; Nieminen, Heikki J. (2019)
    One of the earliest changes in osteoarthritis (OA) is a surface discontinuity of the articular cartilage (AC), and these surface changes become gradually more complex with OA progression. We recently developed a contrast enhanced micro-computed tomography (mu CT) method for visualizing AC surface in detail. The present study aims to introduce a mu CT analysis technique to parameterize these complex AC surface features and to demonstrate the feasibility of using these parameters to quantify degenerated AC surface. Osteochondral plugs (n = 35) extracted from 19 patients undergoing joint surgery were stained with phosphotungstic acid and imaged using mu CT. The surface micro-topography of AC was analyzed with developed method. Standard root mean square roughness (R-q) was calculated as a reference, and the Area Under Curve (AUC) for receiver operating characteristic analysis was used to compare the acquired quantitative parameters with semi-quantitative visual grading of mu CT image stacks. The parameters quantifying the complex micro-topography of AC surface exhibited good sensitivity and specificity in identifying surface continuity (AUC: 0.93, [0.80 0.99]), fissures (AUC: 0.94, [0.83 0.99]) and fibrillation (AUC: 0.98, [0.88 1.0]). Standard R-q was significantly smaller compared with the complex roughness (CRq) already with mild surface changes with all surface reference parameters - continuity, fibrillation, and fissure sum. Furthermore, only CRq showed a significant difference when comparing the intact surface with lowest fissure sum score. These results indicate that the presented method for evaluating complex AC surfaces exhibit potential to identify early OA changes in superficial AC and is dynamic throughout OA progression. (c) 2019 The Authors. Journal of Orthopaedic Research (R) Published by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society. Society. 9999:1-12, 2019.
  • Agustin, Melissa; Penttilä, Paavo; Lahtinen, Maarit; Mikkonen, Kirsi S. (2019)
    The production of lignin nanoparticles (LNPs) has opened new routes to the utilization of lignin in advanced applications. The existing challenge, however, is to develop a production method that can easily be adapted on an industrial scale. In this study, we demonstrated a green and rapid method of preparing LNPs directly from a sulfur-free alkaline pulping liquor by combining acid precipitation and ultrasonication. The combined method produced spherical LNPs, with a hierarchical nanostructure and a highly negative surface charge, within only 5 min of sonication. The mild, rapid sonication was achieved by sonicating directly without prior drying of the acid-precipitated and dialyzed lignin. Optimization of the method revealed the potential for minimizing acid consumption, shortening the dialysis time, and processing directly the alkaline liquor with as much as 20 wt % lignin. The isolated LNPs were stable during storage for 180 days, at a pH range of 4–7, and in a dispersing medium below 0.1 M NaCl. The LNPs also displayed excellent emulsifying properties, stabilizing oil-in-water emulsions. Thus, this simple and energy-efficient method opens a sustainable, straightforward, and scalable route to the production of organic solvent-free LNPs, with high potential as interface stabilizers of multiphase systems in the food and medical industries.
  • Malde, Sachin; Nambiar, Arjun K.; Umbach, Roland; Lam, Thomas B.; Bach, Thorsten; Bachmann, Alexander; Drake, Marcus J.; Gacci, Mauro; Gratzke, Christian; Madersbacher, Stephan; Mamoulakis, Charalampos; Tikkinen, Kari; Gravas, Stavros; European Assoc Urology Non-neuroge (2017)
    Context: Several noninvasive tests have been developed for diagnosing bladder outlet obstruction (BOO) in men to avoid the burden and morbidity associated with invasive urodynamics. The diagnostic accuracy of these tests, however, remains uncertain. Objective: To systematically review available evidence regarding the diagnostic accuracy of noninvasive tests in diagnosing BOO in men with lower urinary tract symptoms (LUTS) using a pressure-flow study as the reference standard. Evidence acquisition: The EMBASE, MEDLINE, Cochrane Database of Systematic Reviews, Cochrane Central, Google Scholar, and WHO International Clinical Trials Registry Platform Search Portal databases were searched up to May 18, 2016. All studies reporting diagnostic accuracy for noninvasive tests for BOO or detrusor underactivity in men with LUTS compared to pressure-flow studies were included. Two reviewers independently screened all articles, searched the reference lists of retrieved articles, and performed the data extraction. The quality of evidence and risk of bias were assessed using the QUADAS-2 tool. Evidence synthesis: The search yielded 2774 potentially relevant reports. After screening titles and abstracts, 53 reports were retrieved for full-text screening, of which 42 (recruiting a total of 4444 patients) were eligible. Overall, the results were predominantly based on findings from nonrandomised experimental studies and, within the limits of such study designs, the quality of evidence was typically moderate across the literature. Differences in noninvasive test threshold values and variations in the urodynamic definition of BOO between studies limited the comparability of the data. Detrusor wall thickness (median sensitivity 82%, specificity 92%), near- infrared spectroscopy (median sensitivity 85%, specificity 87%), and the penile cuff test (median sensitivity 88%, specificity 75%) were all found to have high sensitivity and specificity in diagnosing BOO. Uroflowmetry with a maximum flow rate of 10 mm was reported to have similar diagnostic accuracy, with median sensitivity of 68% and specificity of 75%. Conclusions: According to the literature, a number of noninvasive tests have high sensitivity and specificity in diagnosing BOO in men. However, although the majority of studies have a low overall risk of bias, the available evidence is limited by heterogeneity. While several tests have shown promising results regarding noninvasive assessment of BOO, invasive urodynamics remain the gold standard. Patient summary: Urodynamics is an accurate but potentially uncomfortable test for patients in diagnosing bladder problems such as obstruction. We performed a thorough and comprehensive review of the literature to determine if there were less uncomfortable but equally effective alternatives to urodynamics for diagnosing bladder problems. We found that some simple tests appear to be promising, although they are not as accurate. Further research is needed before these tests are routinely used in place of urodynamics. (C) 2016 European Association of Urology. Published by Elsevier B.V. All rights reserved.
  • El Dib, Regina; Tikkinen, Kari A. O.; Akl, Elie A.; Gomaa, Huda A.; Mustafa, Reem A.; Agarwal, Arnav; Carpenter, Christopher R.; Zhang, Yuchen; Jorge, Eliane C.; Almeida, Ricardo A. M. B.; do Nascimento Junior, Paulo; Doles, Joao Vitor P.; Mustafa, Ahmad A.; Sadeghirad, Behnam; Lopes, Luciane C.; Bergamaschi, Cristiane C.; Suzumura, Erica A.; Cardoso, Marilia M. A.; Corrente, Jose Eduardo; Stone, Samuel B.; Schunemann, Holger J.; Guyatt, Gordon H. (2017)
    Objectives: To provide a perspective on the current practice of randomized clinical trials (RCTs) of diagnostic strategies focusing on patient-important outcomes. Study Design and Setting: We conducted a comprehensive search of MEDLINE and included RCTs published in full-text reports that evaluated alternative diagnostic strategies. Results: Of 56,912 unique citations, we sampled 7,500 and included 103 eligible RCTs, therefore suggesting that MEDLINE includes approximately 781 diagnostic RCTs. The 103 eligible trials reported on: mortality (n = 41; 39.8%); morbidities (n = 63; 61.2%); symptoms/quality of life/functional status (n = 14; 13.6%); and on composite end points (n = 10; 9.7%). Of the studies that reported statistically significant results (n = 12; 11.6%), we judged 7 (58.3%) as at low risk of bias with respect to missing outcome data and 4 (33.3%) as at low risk of bias regarding blinding. Of the 41 RCTs that reported on mortality, only one (2.4%) reported statistically significant results. Of 63 RCTs addressing morbidity outcomes, 11 (17.5%) reported statistically significant results, all of which reported relative effects of greater than 20%. Conclusion: RCTs of diagnostic tests are not uncommon, and sometimes suggest benefits on patient-important outcomes but often suffer from limitations in sample size and conduct. (C) 2017 Elsevier Inc. All rights reserved.
  • Kohout, Tomas; Karlqvist, Ronnie; Lassila, Ilkka Johannes; Eskelinen, Joona Juhani; Hortling, Airi; Pesonen, Lauri; Haeggström, Edward (2013)
    An ultrasonic method was tested to rapidly determine the porosity in custom made ceramic samples. The samples with porosities between 4 and 33% were of identical composition. The porosity estimates by ultrasonic method were validated against those obtained by helium and air pycnometry as well as with Archimedean method. The ultrasonic measurements can be performed rapidly (less than a minute) but they require a well prepared sample.
  • Nevalainen, Mika T.; Kauppinen, Kyösti; Pylväläinen, Juho; Pamilo, Konsta; Pesola, Maija; Haapea, Marianne; Koski, Juhani; Saarakkala, Simo (2018)
    The purpose of this study was to assess the effectiveness of the ultrasonography (US) on detecting osteoarthritis of the knee, and compare US and radiographic findings to intraoperative total knee arthroplasty (TKA) findings. Fifty-seven late-stage osteoarthritic knees undergoing TKA were evaluated with US and radiography. Standard knee US assessing femoral cartilage damage, osteophytes, effusion, synovitis, and meniscal extrusion was performed. On radiographs, osteophytes, joint space narrowing, and Kellgren-Lawrence grade were evaluated. Corresponding intra-operative findings were assessed during TKA as the gold standard. On the damage of the medial femoral condyle cartilage, the sensitivity of US was high (92%), whereas on the lateral condyle and sulcus area, sensitivities were 58% and 46%, respectively. On osteophytes, the detection rate of the US was remarkable especially on the medial side yielding sensitivities of 90-95%. The sensitivities for detecting effusion and synovitis were also excellent (97%). US detection rate of femoral cartilage damage was in concordance with the radiographic joint space narrowing. For the detection of osteophytes, US provided superior results to radiography particularly on the medial side. In conclusion, US can reliably assess the late-stage OA changes of the knee especially on the medial side of the knee joint.