scholarly journals Non‐Invasive Ultrasound Quantification of Scar Tissue Volume Identifies Early Functional Changes During Tendon Healing

2019 ◽  
Vol 37 (11) ◽  
pp. 2476-2485 ◽  
Author(s):  
Jessica E. Ackerman ◽  
Valentina Studentsova ◽  
Marlin Myers ◽  
Mark R. Buckley ◽  
Michael S. Richards ◽  
...  
Keyword(s):  
Tendon Healing ◽  
Scar Tissue ◽  
Functional Changes ◽  
Tissue Volume ◽  
Non Invasive

scholarly journals Non-invasive ultrasound quantification of Scar Tissue Volume predicts functional changes during tendon healing

2018 ◽  
Author(s):  
Jessica E. Ackerman ◽  
Valentina Studentsova ◽  
Alayna E. Loiselle
Keyword(s):  
Tendon Healing ◽  
Cost Effective ◽  
Clinical Problem ◽  
Scar Tissue ◽  
Rapid Screening ◽  
Functional Changes ◽  
Tissue Volume ◽  
Non Invasive ◽  
Effective Manner ◽  
Pathological Scar

AbstractTendon injuries are very common and disrupt the transmission of forces from muscle to bone, leading to impaired function and quality of life. Successful restoration of tendon function after injury is a challenging clinical problem due to the pathological, scar-mediated manner in which tendons heal. Currently, there are no standard treatments to modulate scar tissue formation and improve tendon healing. A major limitation to the identification of therapeutic candidates has been the reliance on terminal end-point metrics of healing in pre-clinical studies, which require a large number of animals and result in destruction of the tissue. To address this limitation, we have identified quantification of Scar Tissue Volume (STV) from ultrasound imaging as a longitudinal, non-invasive metric of tendon healing. STV was strongly correlated with established endpoint metrics of gliding function including Gliding Resistance (GR) and Metatarsophalangeal (MTP) Flexion Angle. However, no associations were observed between STV and tensile mechanical properties. To define the sensitivity of STV to identify differences between functionally discrete tendon healing phenotypes, we utilized S100a4 haploinsufficient mice (S100a4GFP/+), which heal with improved gliding function relative to wildtype (WT) littermates. A significant decrease in STV was observed in S100a4GFP/+repairs, relative to WT at day 14. Taken together, these data suggest US quantification of STV as a means to facilitate the rapid screening of biological and pharmacological interventions to improve tendon healing, and identify promising therapeutic targets, in an efficient, cost-effective manner.

scholarly journals Serial Ultrasonographic and Real-Time Elastosonographic Assessment of the Ovine Common Calcaneal Tendon, after an Experimentally Induced Tendinopathy

2021 ◽  
Vol 8 (4) ◽  
pp. 54
Author(s):  
Daniele Serrani ◽  
Antonella Volta ◽  
Franco Cingolani ◽  
Luca Pennasilico ◽  
Caterina Di Bella ◽  
...  
Keyword(s):  
Real Time ◽  
Statistical Significance ◽  
Healing Process ◽  
Tendon Healing ◽  
Tissue Elasticity ◽  
Calcaneal Tendon ◽  
Non Invasive ◽  
Type Ia ◽  
Single Operator ◽  
Experimentally Induced

Real-time elastosonography (RTE) is a recently described, non-invasive, ultrasonographic technique developed to assess tissue elasticity. The main aim of this study was to investigate the ultrasonographic and elastosonographic appearance of the common calcaneal tendon (CCT) in an ovine model, and to monitor the progression of tendon healing after an experimentally-induced tendinopathy. Sound tendons were initially evaluated (T0) with a caliper and by a single operator with ultrasound. Ultrasonographic and elastosonographic images were then acquired. Subsequently, ultrasound-guided tendon lesions were induced by injecting 500 IU of Type IA collagenases proximally to the calcaneal tuberosity. Caliper measurement, ultrasonography and elastosonography were then repeated at 15 (T1), 30 (T2) and 60 (T3) days. Clinically measured width of the tendon, ultrasonographic thickness and width and percentage of hard (Elx-t%hrd) and soft (Elx-t%sft) tissue were recorded. Statistical analysis was performed on the data collected; statistical significance was set at p < 0.05. Intra-class correlation coefficient (ICC) revealed good (0.68) repeatability of elastosonographic evaluation of the CCT. The tendon width was significantly increased when comparing T0 with T1–2 and decreased when comparing T1–2 with T3. Ultrasound-assessed thickness was significantly increased between T0–T1 and decreased between T1-T2–3. Elx-t%hrd was significantly decreased at T1–2–3 and Elx-t%sft was significantly increased at T1–2–3. In conclusion, the ovine CCT is a highly stiff structure that undergoes a severe loss of stiffness during the healing process. Thickness and width of the tendon increased during the first 30 days and then reduced progressively along the subsequent 30 days. Ultrasonographic appearance of the tendon remained severely abnormal and the tendon showed severely reduced elastic proprieties 60 days after lesion induction.

Hyperpolarized 129Xe Magnetic Resonance Spectroscopy in a Rat Model of Bronchopulmonary Dysplasia

2021 ◽  
Author(s):  
Jordan David Fliss ◽  
Brandon Zanette ◽  
Yonni Friedlander ◽  
Siddharth Sadanand ◽  
Andras A Lindenmaier ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Gas Exchange ◽  
Magnetic Resonance Spectroscopy ◽  
Bronchopulmonary Dysplasia ◽  
Rat Model ◽  
Resonance Spectroscopy ◽  
Gas Exchange Parameters ◽  
Functional Changes ◽  
Non Invasive

Premature infants often require mechanical ventilation and oxygen therapy which can result in bronchopulmonary dysplasia (BPD), characterized by developmental arrest and impaired lung function. Conventional clinical methods for assessing the prenatal lung are not adequate for the detection and assessment of long-term health risks in infants with BPD, highlighting the need for a non-invasive tool for the characterization of lung microstructure and function. Theoretical diffusion models, like the Model of Xenon Exchange (MOXE), interrogate alveolar gas exchange by predicting the uptake of inert Hyperpolarized (HP) 129Xe gas measured with HP 129Xe magnetic resonance spectroscopy (MRS). To investigate HP 129Xe MRS as a tool for non-invasive characterization of pulmonary microstructural and functional changes in vivo, HP 129Xe gas exchange data were acquired in an oxygen exposure rat model of BPD that recapitulates the fewer and larger distal airways and pulmonary vascular stunting characteristics of BPD. Gas exchange parameters from MOXE, including airspace mean chord length (L­m), apparent hematocrit in the pulmonary capillaries (HCT), and pulmonary capillary transit time (tx), were compared with airspace mean axis length and area density (MAL and ρ­A) and percentage area of tissue and air (PTA and PAA) from histology. L­m was significantly larger in the exposed rats (p=0.003) and correlated with MAL, ρ­A, PTA, and PAA (0.59<|ρ|<0.66 and p<0.05). Observed increase in HCT (p=0.012) and changes in tx are also discussed. These findings support the use of HP 129Xe MRS for detecting fewer, enlarged distal airways in this rat model of BPD, and potentially in humans.

scholarly journals Retinal functional imager (RFI): Non-invasive functional imaging of the retina

2013 ◽  
Vol 5 (2) ◽  
pp. 250-257 ◽  
Author(s):  
Sunil Ganekal
Keyword(s):  
Functional Imaging ◽  
Structural Changes ◽  
Imaging System ◽  
Retinal Blood Flow ◽  
Capillary Perfusion ◽  
Functional Changes ◽  
Non Invasive ◽  
Retinal Disorders ◽  
Retinal Blood Flow Velocity ◽  
Perfusion Maps

Retinal functional imager (RFI) is a unique non-invasive functional imaging system with novel capabilities for visualizing the retina. The objective of this review was to show the utility of non-invasive functional imaging in various disorders. Electronic literature search was carried out using the websites www.pubmed.gov and www.google.com. The search words were retinal functional imager and non-invasive retinal imaging used in combination. The articles published or translated into English were studied. The RFI directly measures hemodynamic parameters such as retinal blood-flow velocity, oximetric state, metabolic responses to photic activation and generates capillary perfusion maps (CPM) that provides retinal vasculature detail similar to flourescein angiography. All of these parameters stand in a direct relationship to the function and therefore the health of the retina, and are known to be degraded in the course of retinal diseases. Detecting changes in retinal function aid early diagnosis and treatment as functional changes often precede structural changes in many retinal disorders. Nepal J Ophthalmol 2013; 5(10): 250-257 DOI: http://dx.doi.org/10.3126/nepjoph.v5i2.8738

scholarly journals Study of Osteocyte Behavior by High-Resolution Intravital Imaging Following Photo-Induced Ischemia

Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 2874
Author(s):  
Hengfeng Yuan ◽  
Wen Jiang ◽  
Yuanxin Chen ◽  
Betty Kim
Keyword(s):  
Imaging Techniques ◽  
Avascular Osteonecrosis ◽  
Functional Changes ◽  
Cellular Processes ◽  
Non Invasive ◽  
Behavioral Dynamics ◽  
Bony Anatomy ◽  
Magnetic Resonance Imaging Mri

Ischemic injuries and local hypoxia can result in osteocytes dysfunction and play a key role in the pathogenesis of avascular osteonecrosis. Conventional imaging techniques including magnetic resonance imaging (MRI) and computed tomography (CT) can reveal structural and functional changes within bony anatomy; however, characterization of osteocyte behavioral dynamics in the setting of osteonecrosis at the single cell resolution is limited. Here, we demonstrate an optical approach to study real-time osteocyte functions in vivo. Using nicotinamide adenine dinucleotide (NADH) as a biomarker for metabolic dynamics in osteocytes, we showed that NADH level within osteocytes transiently increase significantly after local ischemia through non-invasive photo-induced thrombosis of afferent arterioles followed by a steady decline. Our study presents a non-invasive optical approach to study osteocyte behavior through the modulation of local environmental conditions. Thus it provides a powerful toolkit to study cellular processes involved in bone pathologies in vivo.

scholarly journals Characterization of scar tissue biomechanics during adult murine flexor tendon healing

2021 ◽  
Author(s):  
Antonion Korcari ◽  
Alayna E Loiselle ◽  
Mark R Buckley
Keyword(s):  
Mechanical Properties ◽  
Material Properties ◽  
Healing Process ◽  
Tendon Healing ◽  
Scar Tissue ◽  
Element Analysis ◽  
Material Quality ◽  
Treatment Regimens ◽  
Tangent Moduli ◽  
Experimental Findings

Tendon injuries are very common and result in significant impairments in mobility and quality of life. During healing, tendons produce a scar at the injury site, characterized by abundant and disorganized extracellular matrix and by permanent deficits in mechanical integrity compared to healthy tendon. Although a significant amount of work has been done to understand the healing process of tendons and to develop potential therapeutics for tendon regeneration, there is still a significant gap in terms of assessing the direct effects of therapeutics on the functional and material quality specifically of the scar tissue, and thus, on the overall tendon healing process. In this study, we focused on characterizing the mechanical properties of only the scar tissue in flexor digitorum longus (FDL) tendons during the proliferative and remodeling healing phases and comparing these properties with the mechanical properties of the composite healing tissue. Our method was sensitive enough to identify significant differences in structural and material properties between the scar and tendon-scar composite tissues. To account for possible inaccuracies due to the small aspect ratio of scar tissue, we also applied inverse finite element analysis (iFEA) to compute mechanical properties based on simulated tests with accurate specimen geometries and boundary conditions. We found that the scar tissue linear tangent moduli calculated from iFEA were not significantly different from those calculated experimentally at all healing timepoints, validating our experimental findings, and suggesting the assumptions in our experimental calculations were accurate. Taken together, this study first demonstrates that due to the presence of uninjured stubs, testing composite healing tendons without isolating the scar tissue overestimates the material properties of the scar itself. Second, our scar isolation method promises to enable more direct assessment of how different treatment regimens (e.g., cellular ablation, biomechanical and/or biochemical stimuli, tissue engineered scaffolds) affect scar tissue function and material quality in multiple different types of tendons.

scholarly journals Cosmetic Gynecology: Present and Future Perspectives

2021 ◽  
Vol 6 (11) ◽  
pp. 845-853
Author(s):  
Prabhu Chandra Mishra ◽  
Diana Mihai ◽  
Nidhi Khurana ◽  
Manar Jabbar
Keyword(s):  
Well Being ◽  
Physical Structure ◽  
Fat Grafting ◽  
Functional Changes ◽  
Non Invasive ◽  
High Prevalence ◽  
Regulatory Guidelines ◽  
Stem Cells Therapy ◽  
Cosmetic Gynecology

Postmenopausal women and events like childbirth, and aging may cause structural and functional changes in women genitalia. The arising indications do not only cause psychological distress to women but negatively affect the sexual well-being and deteriorate the quality of their lives. Regenerative/ cosmetic gynecology procedures enable women to treat the functionality issues and modify the physical structure of vagina. This review discusses the latest developments in this field with regards to various kinds of procedures that are available, particularly the use of energy-based devices, and adipose tissue derived stem cells therapy for fat grafting which have revolutionized the regenerative gynecology procedures. These offer non-invasive modalities to treat the conditions like urinary incontinence among others which occur in high prevalence among women. Despite the advancements made in this field, it lacks regulatory guidelines and standardized procedures which imposes one of the biggest challenges of the field. Alongside, we have documented a procedure called Intimacell® which has been standardized for fat grafting procedures in vulvovaginal region.

Temporomandibular Joint Kinematics of the Rabbit Model With Mechanically Disrupted Occlusion

2011 ◽  
Author(s):  
Sarah E. Henderson ◽  
Alejandro J. Almarza ◽  
Scott Tashman ◽  
Amy L. McCarty
Keyword(s):  
Temporomandibular Joint ◽  
Rabbit Model ◽  
Specific Pattern ◽  
Therapeutic Interventions ◽  
Irreversible Damage ◽  
Invasive Approach ◽  
Functional Changes ◽  
Factors Associated ◽  
Non Invasive ◽  
Injury Model

Degeneration of the articulating surfaces and pain associated with temporomandibular joint (TMJ) dysfunction are the primary symptoms of TMJ disorders (TMDs), where normal life activities such as eating, talking, and even sleeping may be drastically impaired [1–3]. To accelerate the discovery of effective therapeutic interventions for the treatment of TMD pain, we have been establishing a novel non-invasive approach for objectively assessing the presence of joint hypersensitivity. Our approach to identify chronic joint pain is based on evidence that all of the etiological factors associated with TMD pain implicate remodeling and degeneration of the joint in response to alterations in motion and loading. The injury model used for this study was a reversible, mechanical model through splint placement on the molars. It is hypothesized that arthrokinematic analysis will identify a specific pattern of functional changes that constitute a signature for the presence of irreversible damage.

scholarly journals Murine patellar tendon transplantation requires transosseous cerclage augmentation — development of a transplantation model for investigation of systemic and local drivers of healing

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Borys Frankewycz ◽  
Daniel Cimino ◽  
Nelly Andarawis-Puri
Keyword(s):  
Patellar Tendon ◽  
Surgical Techniques ◽  
Tendon Healing ◽  
Knee Extensor ◽  
Scar Tissue ◽  
Quadriceps Muscle ◽  
Gap Formation ◽  
Tendon Transplantation ◽  
Transfascial Suture ◽  
Transplantation Model

Abstract Background Tendon injuries are common musculoskeletal injuries that heal with scar tissue formation, often achieving reduced biomechanical and functional properties. The murine patellar tendon is a research tool that holds potential for investigating tendon healing and can be useful for exploring therapeutic strategies. Since healing is a complex process that results from the collaboration between the systemic and local tissue environment, a murine tendon transplantation model that can be applied to transgenic mice and genetic mutants would allow isolation of systemic versus local tendon factors in driving effective tendon healing. Preliminary studies have shown that transplantation with simple tendon sutures results in a proximalization of the patellar bone due to the involuntary quadriceps muscle force leading to tearing of the graft and failure of the knee extensor mechanism. To avoid this elongation of the graft, two cerclage techniques for murine patellar tendon transplantation were introduced and validated. Methods Three developed surgical techniques (no-cerclage-augmentation (NCA)), transfascial suture cerclage with encirclement of the patellar tendon (TFSC), and dual-cerclage-augmentation with a transosseous bone-to-bone cerclage through the patella bone and an additional musculotendinous cerclage (DCA)) were compared at 4 and 8 weeks macroscopically in regards to graft continuity, cerclage integrity, gap formation, and radiologically by measuring the patello-tibial distance and using a patella bone position grading system. Results The NCA group showed complete failure at 5–7 days after surgery. The TFSC has led to 69% functional failure of the cerclage. In contrast, the DCA with a has led to 78% success with improvement in patellar bone position and a similar patello-tibial distance to the naïve contralateral murine knees over the time period of 8 weeks. Conclusions This study shows that a bone-to-bone cerclage is necessary to maintain a desired graft length in murine patellar tendon models. This surgery technique can serve for future graft trans- and implantations in the murine patellar tendon.

scholarly journals Thermal response of hands to computer work: comparison of three assessment procedures

2019 ◽  
Vol 13 (1) ◽  
pp. 27-39
Author(s):  
Jan Horáček ◽  
Jan Novotný
Keyword(s):  
Thermal Response ◽  
Computer Work ◽  
Temperature Changes ◽  
Functional Changes ◽  
Non Invasive ◽  
Thermal Changes ◽  
Thermographic Camera ◽  
Assessment Procedures ◽  
Office Employees ◽  
Higher Sensitivity

Introduction: Unlike other imaging modalities thermography is absolutely non-invasive and suitable to assess functional changes. However in some fields, methodology for its use has not even been set yet. This work compares three different methods to study the dynamics of skin temperature changes in hands during computer work. Methods: A total of 306 measurements of 20 office employees and 6 non-office employees was performed with a thermographic camera during a work shift. The thermograms were subsequently evaluated and three methodologies - regions of interest, two of them newly proposed - were compared mathematically. Also, two more have been taken into consideration. Results: The results shown the same tendencies of thermal changes comparing our methodologies with the methodology used earlier in more than 80% (88 % in case of the first method, named H2 method and 85 % in case of the second one, named H5). However, in comparison to older procedure, our procedures shown higher sensitivity to temperature changes in more than 60% of cases (61 % in case of the first method and 68 % in case of the second one). We measured a variation range difference of 1.6 °C, and, with the second method, whole 2.1 °C compared to method used earlier. Conclusion: This work has determined a new procedure for measuring of dynamics of hands temperature changes, which is not only easier and faster to perform and evaluate, but it is also more capable of detecting temperature changes on hands.

Sign in / Sign up

Export Citation Format

Share Document