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Guven AE, Chiapparelli E, Camino-Willhuber G, Zhu J, Schönnagel L, Amoroso K, Caffard T, Erduran A, Shue J, Sama AA, Girardi FP, Cammisa FP, Hughes AP. Assessing paraspinal muscle atrophy with electrical impedance myography: Limitations and insights. J Orthop Res 2024. [PMID: 38594874 DOI: 10.1002/jor.25848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 03/21/2024] [Accepted: 03/27/2024] [Indexed: 04/11/2024]
Abstract
Paraspinal muscle atrophy is gaining attention in spine surgery due to its link to back pain, spinal degeneration and worse postoperative outcomes. Electrical impedance myography (EIM) is a noninvasive diagnostic tool for muscle quality assessment, primarily utilized for patients with neuromuscular diseases. However, EIM's accuracy for paraspinal muscle assessment remains understudied. In this study, we investigated the correlation between EIM readings and MRI-derived muscle parameters, as well as the influence of dermal and subcutaneous parameters on these readings. We retrospectively analyzed patients with lumbar spinal degeneration who underwent paraspinal EIM assessment between May 2023 to July 2023. Paraspinal muscle fatty infiltration (FI) and functional cross-sectional area (fCSA), as well as the subcutaneous thickness were assessed on MRI scans. Skin ultrasound imaging was assessed for dermal thickness and the echogenicities of the dermal and subcutaneous layers. All measurements were performed on the bilaterally. The correlation between EIM readings were compared with ultrasound and MRI parameters using Spearman's correlation analyses. A total of 20 patients (65.0% female) with a median age of 69.5 years (IQR, 61.3-73.8) were analyzed. The fCSA and FI did not significantly correlate with the EIM readings, regardless of frequency. All EIM readings across frequencies correlated with subcutaneous thickness, echogenicity, or dermal thickness. With the current methodology, paraspinal EIM is not a valid alternative to MRI assessment of muscle quality, as it is strongly influenced by the dermal and subcutaneous layers. Further studies are required for refining the methodology and confirming our results.
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Affiliation(s)
- Ali E Guven
- Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Cornell Medicine, New York, USA
| | - Erika Chiapparelli
- Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Cornell Medicine, New York, USA
| | - Gaston Camino-Willhuber
- Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Cornell Medicine, New York, USA
| | - Jiaqi Zhu
- Biostatistics Core, Hospital for Special Surgery, New York, USA
| | - Lukas Schönnagel
- Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Cornell Medicine, New York, USA
- Center for Musculoskeletal Surgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Krizia Amoroso
- Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Cornell Medicine, New York, USA
| | - Thomas Caffard
- Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Cornell Medicine, New York, USA
- Universitätsklinikum Ulm, Klinik für Orthopädie, Ulm, Germany
| | - Ada Erduran
- Department of Electrical Engineering, Technical University Berlin, Berlin, Germany
| | - Jennifer Shue
- Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Cornell Medicine, New York, USA
| | - Andrew A Sama
- Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Cornell Medicine, New York, USA
| | - Federico P Girardi
- Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Cornell Medicine, New York, USA
| | - Frank P Cammisa
- Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Cornell Medicine, New York, USA
| | - Alexander P Hughes
- Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Cornell Medicine, New York, USA
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Offit MB, Khanli HM, Wu T, Lehky TJ. Electrical impedance myography in healthy volunteers. Muscle Nerve 2024; 69:288-294. [PMID: 37787098 PMCID: PMC10922034 DOI: 10.1002/mus.27978] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 09/07/2023] [Accepted: 09/10/2023] [Indexed: 10/04/2023]
Abstract
INTRODUCTION/AIMS Electrical impedance myography (EIM) is a noninvasive technique being used in clinical studies to characterize muscle by phase, reactance, and resistance after application of a low-intensity current. The aim of this study was to obtain 50-kHz EIM data from healthy volunteers (HVs) for use in future clinical and research studies, perform reliability tests on EIM outcome measures, and compare findings with muscle ultrasound variables. METHODS Four arm and four leg muscles of HVs were evaluated using an EIM device with two sensors, P/N 20-0045 and P/N 014-009. Muscles were evaluated individually and eight-muscle average (8MU), four-muscle upper extremity average, and four-muscle lower extremity average. An intraclass correlation coefficient (ICC) was applied to assess interrater, intrarater, and intersensor reliability using a subset of HVs. Ultrasound studies on muscle thickness and elastography were also performed on a subset of HVs. RESULTS For the P/N 20-0045 sensor, the 8MU EIM mean and standard deviation (n = 41) was 14.54 ± 3.31 for phase, 7.04 ± 1.22 for reactance, and 28.91 ± 7.63 for resistance. Reliability for 8MU phase (n = 22) was good to excellent for both interrater (n = 22, ICC = 0.920, 95% CI 0.820 to 0.966) and intrarater (n = 22, ICC = 0.950, 95% CI 0.778 to 0.983). The P/N 014-009 sensor had similar reliability findings. Correlation analyses showed no association between EIM and muscle thickness. DISCUSSION EIM is a reproducible measure of muscle physiology. Obtaining EIM values from HVs allows us to gain a better understanding how EIM may be altered in diseased muscle.
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Affiliation(s)
- Michelle B. Offit
- Electromyography Section, National Institutes of Health of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
- Neurology Department, Georgetown University, Washington, DC, USA
| | - Hadi Mohammad Khanli
- Electromyography Section, National Institutes of Health of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
- Neurology Department, City of Hope Comprehensive Cancer Center, Duarte, California, USA
| | - Tianxia Wu
- Clinical Trials Unit, National Institutes of Health of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Tanya J. Lehky
- Electromyography Section, National Institutes of Health of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
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McDonald C, Camino E, Escandon R, Finkel RS, Fischer R, Flanigan K, Furlong P, Juhasz R, Martin AS, Villa C, Sweeney HL. Draft Guidance for Industry Duchenne Muscular Dystrophy, Becker Muscular Dystrophy, and Related Dystrophinopathies - Developing Potential Treatments for the Entire Spectrum of Disease. J Neuromuscul Dis 2024; 11:499-523. [PMID: 38363616 DOI: 10.3233/jnd-230219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Background Duchenne muscular dystrophy (DMD) and related dystrophinopathies are neuromuscular conditions with great unmet medical needs that require the development of effective medical treatments. Objective To aid sponsors in clinical development of drugs and therapeutic biological products for treating DMD across the disease spectrum by integrating advancements, patient registries, natural history studies, and more into a comprehensive guidance. Methods This guidance emerged from collaboration between the FDA, the Duchenne community, and industry stakeholders. It entailed a structured approach, involving multiple committees and boards. From its inception in 2014, the guidance underwent revisions incorporating insights from gene therapy studies, cardiac function research, and innovative clinical trial designs. Results The guidance provides a deeper understanding of DMD and its variants, focusing on patient engagement, diagnostic criteria, natural history, biomarkers, and clinical trials. It underscores patient-focused drug development, the significance of dystrophin as a biomarker, and the pivotal role of magnetic resonance imaging in assessing disease progression. Additionally, the guidance addresses cardiomyopathy's prominence in DMD and the burgeoning field of gene therapy. Conclusions The updated guidance offers a comprehensive understanding of DMD, emphasizing patient-centric approaches, innovative trial designs, and the importance of biomarkers. The focus on cardiomyopathy and gene therapy signifies the evolving realm of DMD research. It acts as a crucial roadmap for sponsors, potentially leading to improved treatments for DMD.
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Affiliation(s)
| | - Eric Camino
- Parent Project Muscular Dystrophy, Washington, DC, USA
| | - Rafael Escandon
- DGBI Consulting, LLC, Bainbridge Island, Washington, DC, USA
| | | | - Ryan Fischer
- Parent Project Muscular Dystrophy, Washington, DC, USA
| | - Kevin Flanigan
- Center for Experimental Neurotherapeutics, Department of Pediatric Medicine, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Pat Furlong
- Parent Project Muscular Dystrophy, Washington, DC, USA
| | - Rose Juhasz
- Nationwide Children's Hospital, Columbus, OH, USA
| | - Ann S Martin
- Parent Project Muscular Dystrophy, Washington, DC, USA
| | - Chet Villa
- Trinity Health Michigan, Grand Rapids, MI, USA
| | - H Lee Sweeney
- Cincinnati Children's Hospital Medical Center within the UC Department of Pediatrics, Cincinnati, OH, USA
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Hiyoshi T, Zhao F, Baba R, Hirakawa T, Kuboki R, Suzuki K, Tomimatsu Y, O'Donnell P, Han S, Zach N, Nakashima M. Electrical impedance myography detects dystrophin-related muscle changes in mdx mice. Skelet Muscle 2023; 13:19. [PMID: 37980539 PMCID: PMC10657153 DOI: 10.1186/s13395-023-00331-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 10/27/2023] [Indexed: 11/20/2023] Open
Abstract
BACKGROUND The lack of functional dystrophin protein in Duchenne muscular dystrophy (DMD) causes chronic skeletal muscle inflammation and degeneration. Therefore, the restoration of functional dystrophin levels is a fundamental approach for DMD therapy. Electrical impedance myography (EIM) is an emerging tool that provides noninvasive monitoring of muscle conditions and has been suggested as a treatment response biomarker in diverse indications. Although magnetic resonance imaging (MRI) of skeletal muscles has become a standard measurement in clinical trials for DMD, EIM offers distinct advantages, such as portability, user-friendliness, and reduced cost, allowing for remote monitoring of disease progression or response to therapy. To investigate the potential of EIM as a biomarker for DMD, we compared longitudinal EIM data with MRI/histopathological data from an X-linked muscular dystrophy (mdx) mouse model of DMD. In addition, we investigated whether EIM could detect dystrophin-related changes in muscles using antisense-mediated exon skipping in mdx mice. METHODS The MRI data for muscle T2, the magnetic resonance spectroscopy (MRS) data for fat fraction, and three EIM parameters with histopathology were longitudinally obtained from the hindlimb muscles of wild-type (WT) and mdx mice. In the EIM study, a cell-penetrating peptide (Pip9b2) conjugated antisense phosphorodiamidate morpholino oligomer (PPMO), designed to induce exon-skipping and restore functional dystrophin production, was administered intravenously to mdx mice. RESULTS MRI imaging in mdx mice showed higher T2 intensity at 6 weeks of age in hindlimb muscles compared to WT mice, which decreased at ≥ 9 weeks of age. In contrast, EIM reactance began to decline at 12 weeks of age, with peak reduction at 18 weeks of age in mdx mice. This decline was associated with myofiber atrophy and connective tissue infiltration in the skeletal muscles. Repeated dosing of PPMO (10 mg/kg, 4 times every 2 weeks) in mdx mice led to an increase in muscular dystrophin protein and reversed the decrease in EIM reactance. CONCLUSIONS These findings suggest that muscle T2 MRI is sensitive to the early inflammatory response associated with dystrophin deficiency, whereas EIM provides a valuable biomarker for the noninvasive monitoring of subsequent changes in skeletal muscle composition. Furthermore, EIM reactance has the potential to monitor dystrophin-deficient muscle abnormalities and their recovery in response to antisense-mediated exon skipping.
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Affiliation(s)
- Tetsuaki Hiyoshi
- Neuroscience Translational Medicine, Neuroscience Drug Discovery Unit, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-Chome, Fujisawa, Kanagawa, 251-8555, Japan
| | - Fuqiang Zhao
- Center of Excellence for Imaging, Preclinical and Translational Sciences, Takeda Development Center Americas, Inc., 95 Hayden Avenue, Lexington, MA, 02141, USA
| | - Rina Baba
- Muscular Disease and Neuropathy Unit, Neuroscience Drug Discovery Unit, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-Chome, Fujisawa, Kanagawa, 251-8555, Japan
| | - Takeshi Hirakawa
- Muscular Disease and Neuropathy Unit, Neuroscience Drug Discovery Unit, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-Chome, Fujisawa, Kanagawa, 251-8555, Japan
| | - Ryosuke Kuboki
- Muscular Disease and Neuropathy Unit, Neuroscience Drug Discovery Unit, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-Chome, Fujisawa, Kanagawa, 251-8555, Japan
| | - Kazunori Suzuki
- Muscular Disease and Neuropathy Unit, Neuroscience Drug Discovery Unit, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-Chome, Fujisawa, Kanagawa, 251-8555, Japan
| | - Yoshiro Tomimatsu
- Neuroscience Translational Medicine, Neuroscience Drug Discovery Unit, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-Chome, Fujisawa, Kanagawa, 251-8555, Japan
| | - Patricio O'Donnell
- Neuroscience Translational Medicine, Neuroscience Drug Discovery Unit, Takeda Development Center Americas, Inc., 95 Hayden Avenue, Lexington, MA, 02141, USA
| | - Steve Han
- Neuroscience Therapeutic Area Unit, Takeda Development Center Americas, Inc., 95 Hayden Avenue, Lexington, MA, 02141, USA
| | - Neta Zach
- Neuroscience Translational Medicine, Neuroscience Drug Discovery Unit, Takeda Development Center Americas, Inc., 95 Hayden Avenue, Lexington, MA, 02141, USA
| | - Masato Nakashima
- Neuroscience Translational Medicine, Neuroscience Drug Discovery Unit, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-Chome, Fujisawa, Kanagawa, 251-8555, Japan.
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Wang HHS, Thaker H, Bigger-Allen A, Nagy JA, Rutkove SB. Novel phenotype characterization utilizing electrical impedance myography signatures in murine spinal cord injury neurogenic bladder models. Sci Rep 2023; 13:19520. [PMID: 37945675 PMCID: PMC10636012 DOI: 10.1038/s41598-023-46740-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 11/04/2023] [Indexed: 11/12/2023] Open
Abstract
Neurogenic bladder (NB) affects people of all ages. Electric impedance myography (EIM) assesses localized muscle abnormalities. Here, we sought to investigate whether unique detrusor EIM signatures are present in NB due to spinal cord injury (SCI). Twenty-eight, 8-10 weeks old, C57BL/6J female mice were studied. Twenty underwent spinal cord transection; 8 served as controls. Cohorts were euthanized at 4 and 6 weeks after spinal cord transection. Each bladder was measured in-situ with EIM with applied frequencies of 1 kHz to 10 MHz, and then processed for molecular and histologic study. SCI mice had greater bladder-to-body weight ratio (p < 0.0001), greater collagen deposition (p = 0.009), and greater smooth-muscle-myosin-heavy-chain isoform A/B ratio (p < 0.0001). Compared with the control group, the SCI group was associated with lower phase, reactance, and resistance values (p < 0.01). Significant correlations (p < 0.001) between bladder-to-body weight ratios and EIM measurements were observed across the entire frequency spectrum. A severely hypertrophied phenotype was characterized by even greater bladder-to-body weight ratios and more depressed EIM values. Our study demonstrated distinct EIM alterations in the detrusor muscle of mice with NB due to SCI. With further refinement, EIM may offer a potential point-of-care tool for the assessment of NB and its response to treatment.
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Affiliation(s)
- Hsin-Hsiao Scott Wang
- Department of Urology, Boston Children's Hospital, 300 Longwood Ave, HU390, Boston, MA, USA.
- Harvard Medical School, Boston, MA, 02215, USA.
| | - Hatim Thaker
- Department of Urology, Boston Children's Hospital, 300 Longwood Ave, HU390, Boston, MA, USA
- Harvard Medical School, Boston, MA, 02215, USA
| | - Alex Bigger-Allen
- Department of Urology, Boston Children's Hospital, 300 Longwood Ave, HU390, Boston, MA, USA
| | - Janice A Nagy
- Harvard Medical School, Boston, MA, 02215, USA
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Seward B Rutkove
- Harvard Medical School, Boston, MA, 02215, USA
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA
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Pandeya S, Sanchez B, Nagy JA, Rutkove SB. Combining electromyographic and electrical impedance data sets through machine learning: A study in D2-mdx and wild-type mice. Muscle Nerve 2023; 68:781-788. [PMID: 37658820 DOI: 10.1002/mus.27963] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 08/10/2023] [Accepted: 08/12/2023] [Indexed: 09/05/2023]
Abstract
INTRODUCTION/AIMS Needle impedance-electromyography (iEMG) assesses the active and passive electrical properties of muscles concurrently by using a novel needle with six electrodes, two for EMG and four for electrical impedance myography (EIM). Here, we assessed an approach for combining multifrequency EMG and EIM data via machine learning (ML) to discriminate D2-mdx muscular dystrophy and wild-type (WT) mouse skeletal muscle. METHODS iEMG data were obtained from quadriceps of D2-mdx mice, a muscular dystrophy model, and WT animals. EIM data were collected with the animals under deep anesthesia and EMG data collected under light anesthesia, allowing for limited spontaneous movement. Fourier transformation was performed on the EMG data to provide power spectra that were sampled across the frequency range using three different approaches. Random forest-based, nested ML was applied to the EIM and EMG data sets separately and then together to assess healthy versus disease category classification using a nested cross-validation procedure. RESULTS Data from 20 D2-mdx and 20 WT limbs were analyzed. EIM data fared better than EMG data in differentiating healthy from disease mice with 93.1% versus 75.6% accuracy, respectively. Combining EIM and EMG data sets yielded similar performance as EIM data alone with 92.2% accuracy. DISCUSSION We have demonstrated an ML-based approach for combining EIM and EMG data obtained with an iEMG needle. While EIM-EMG in combination fared no better than EIM alone with this data set, the approach used here demonstrates a novel method of combining the two techniques to characterize the full electrical properties of skeletal muscle.
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Affiliation(s)
- Sarbesh Pandeya
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Benjamin Sanchez
- Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah, USA
| | - Janice A Nagy
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Seward B Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
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Farid AR, Golden E, Hu A, Robicheau S, Rutkove S, Al-Hertani W, Upadhyay J. A pilot investigation of muscle integrity in patients with ADSSL1 myopathy using electrical impedance myography. Muscle Nerve 2023; 68:775-780. [PMID: 37682022 DOI: 10.1002/mus.27971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 08/21/2023] [Accepted: 08/22/2023] [Indexed: 09/09/2023]
Abstract
INTRODUCTION/AIMS ADSSL1 myopathy (OMIM 617030) is a recently discovered, congenital myopathic disease caused by a pathogenic variant in ADSSL1. ADSSL1 is an enzyme involved in the purine nucleotide process and facilitates the conversion of inosine monophosphate to adenosine monophosphate within myocytes. Electrical impedance myography (EIM) is a portable, non-invasive, and cost-effective method for characterizing muscle integrity. Three ADSSL1 patients are presented in whom characterization of muscle integrity using EIM was performed. METHODS A 15-y-old male, 20-y-old female, and 63-y-old male each with a pathogenic variant in ADSSL1 [c.901G > A] as well as three, age-gender matched healthy controls (HCs) were enrolled. Study participants were phenotyped using a virtual EIM procedure. RESULTS ADSSL1 myopathy patients presented with variable onset of physical disability, disease progression, and severity of muscle weakness. Across multiple proximal and distal muscles groups and relative to HCs, ADSSL1 myopathy patients demonstrated lower phase and reactance values, while resistance was higher, which together indicated diseased muscle. DISCUSSION EIM can provide a novel, non-invasive and objective biomarker to evaluate muscle integrity in patients with ADSSL1 myopathy. Combining EIM with musculoskeletal imaging and histologic assessments in follow-up studies may further inform on the pathophysiology of ADSSL1 myopathy.
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Affiliation(s)
- Alexander Rashad Farid
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Emma Golden
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Alice Hu
- Myolex Inc, Boston, Massachusetts, USA
| | | | - Seward Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Walla Al-Hertani
- Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Jaymin Upadhyay
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Department of Psychiatry, McLean Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Lechtig A, Hanna P, Nagy JA, Wixted J, Nazarian A, Rutkove SB. Electrical impedance myography for the early detection of muscle ischemia secondary to compartment syndrome: a study in a rat model. Sci Rep 2023; 13:18252. [PMID: 37880267 PMCID: PMC10600169 DOI: 10.1038/s41598-023-45209-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 10/17/2023] [Indexed: 10/27/2023] Open
Abstract
Acute Compartment Syndrome (ACS) is one of the most devastating orthopedic conditions, affecting any of the body's many compartments, which, if sufficiently severe, may result in disability and amputation. Currently, intra-compartmental pressure measurements serve as the gold standard for diagnosing ACS. Diagnosing limbs at risk for ACS before irreversible damage to muscle and nerve is critical. Standard approaches for diagnosing impending compartment syndrome include clinical evaluation of the limb, such as assessment for "tightness" of the overlying skin, reduced pulses distally, and degree of pain, none of which are specific or sensitive. We have proposed a novel method to detect ACS via electrical impedance myography (EIM), where a weak, high-frequency alternating current is passed between one pair of electrodes through a region of tissue, and the resulting surface voltages are measured via a second pair. We evaluated the ability of EIM to detect early muscle ischemia in an established murine model of compression-induced muscle injury, where we collected resistance, reactance, and their dimensionless product, defined as Relative Injury Index (RII) during the study. Our model generated reproducible hypoxia, confirmed by Hypoxyprobe™ staining of endothelial regions within the muscle. Under conditions of ischemia, we demonstrated a reproducible, stable, and significant escalation in resistance, reactance, and RII values, compared to uninjured control limbs. These data make a reasonable argument for additional investigations into using EIM for the early recognition of muscle hypoperfusion and ischemia. However, these findings must be considered preliminary steps, requiring further pre-clinical and clinical validation.
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Affiliation(s)
- Aron Lechtig
- Musculoskeletal Translational Innovation Initiative, Carl J. Shapiro Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Philip Hanna
- Musculoskeletal Translational Innovation Initiative, Carl J. Shapiro Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Janice A Nagy
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, 02215, USA
| | - John Wixted
- Musculoskeletal Translational Innovation Initiative, Carl J. Shapiro Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Ara Nazarian
- Musculoskeletal Translational Innovation Initiative, Carl J. Shapiro Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
- Department of Orthopaedic Surgery, Yerevan State Medical University, Yerevan, Armenia
| | - Seward B Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, 02215, USA.
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Rutkove SB, Chen ZZ, Pandeya S, Callegari S, Mourey T, Nagy JA, Nath AK. Surface Electrical Impedance Myography Detects Skeletal Muscle Atrophy in Aged Wildtype Zebrafish and Aged gpr27 Knockout Zebrafish. Biomedicines 2023; 11:1938. [PMID: 37509577 PMCID: PMC10377526 DOI: 10.3390/biomedicines11071938] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 07/03/2023] [Accepted: 07/05/2023] [Indexed: 07/30/2023] Open
Abstract
Throughout a vertebrate organism's lifespan, skeletal muscle mass and function progressively decline. This age-related condition is termed sarcopenia. In humans, sarcopenia is associated with risk of falling, cardiovascular disease, and all-cause mortality. As the world population ages, projected to reach 2 billion older adults worldwide in 2050, the economic burden on the healthcare system is also projected to increase considerably. Currently, there are no pharmacological treatments for sarcopenia, and given the long-term nature of aging studies, high-throughput chemical screens are impractical in mammalian models. Zebrafish is a promising, up-and-coming vertebrate model in the field of sarcopenia that could fill this gap. Here, we developed a surface electrical impedance myography (sEIM) platform to assess skeletal muscle health, quantitatively and noninvasively, in adult zebrafish (young, aged, and genetic mutant animals). In aged zebrafish (~85% lifespan) as compared to young zebrafish (~20% lifespan), sEIM parameters (2 kHz phase angle, 2 kHz reactance, and 2 kHz resistance) robustly detected muscle atrophy (p < 0.000001, q = 0.000002; p = 0.000004, q = 0.000006; p = 0.000867, q = 0.000683, respectively). Moreover, these same measurements exhibited strong correlations with an established morphometric parameter of muscle atrophy (myofiber cross-sectional area), as determined by histological-based morphometric analysis (r = 0.831, p = 2 × 10-12; r = 0.6959, p = 2 × 10-8; and r = 0.7220; p = 4 × 10-9, respectively). Finally, the genetic deletion of gpr27, an orphan G-protein coupled receptor (GPCR), exacerbated the atrophy of skeletal muscle in aged animals, as evidenced by both sEIM and histology. In conclusion, the data here show that surface EIM techniques can effectively discriminate between healthy young and sarcopenic aged muscle as well as the advanced atrophied muscle in the gpr27 KO animals. Moreover, these studies show how EIM values correlate with cell size across the animals, making it potentially possible to utilize sEIM as a "virtual biopsy" in zebrafish to noninvasively assess myofiber atrophy, a valuable measure for muscle and gerontology research.
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Affiliation(s)
- Seward B. Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA; (S.B.R.); (J.A.N.)
| | - Zsu-Zsu Chen
- Department of Endocrinology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
- Department of Cardiology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
| | - Sarbesh Pandeya
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA; (S.B.R.); (J.A.N.)
| | - Santiago Callegari
- Department of Cardiology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
| | - Tyler Mourey
- Zebrafish Core Facility, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
| | - Janice A. Nagy
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA; (S.B.R.); (J.A.N.)
| | - Anjali K. Nath
- Department of Cardiology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
- Broad Institute, Cambridge, MA 02142, USA
- Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
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Chrzanowski SM, Nagy JA, Pandeya S, Rutkove SB. Electrical Impedance Myography Correlates with Functional Measures of Disease Progression in D2-mdx Mice and Boys with Duchenne Muscular Dystrophy. J Neuromuscul Dis 2023; 10:81-90. [PMID: 36442205 DOI: 10.3233/jnd-210787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Sensitive, objective, and longitudinal outcome measures applicable to both pre-clinical and clinical interventions are needed to assess muscle health in Duchenne muscular dystrophy (DMD). Electrical impedance myography (EIM) has the potential to non-invasively measure disease progression in mice and boys with DMD. OBJECTIVE We sought to evaluate how electrical impedance values (i.e., phase, reactance, and resistance) correlate to established measures of disease in both D2-mdx and wild type (WT) mice and boys with and without DMD. METHODS Histological, functional, and EIM data collected from previous studies of WT and D2-mdx mice at 6, 13, 21 and 43 weeks of age were reanalyzed. In parallel, previously collected functional outcome measures and EIM values were reanalyzed from boys with and without DMD at four different age groups from 2 to 14 years old. RESULTS In mice, disease progression as detected by histological, functional, and EIM measures, was appreciable over this time period and grip strength best correlated to longitudinal phase and reactance impedance values. In boys, disease progression quantified through commonly utilized functional outcome measures was significant and longitudinal phase demonstrated the strongest correlation with functional outcome measures. CONCLUSION Similar changes in EIM values, specifically in longitudinal reactance and phase, were found to show significant correlations to functional measures in both mice and boys. Thus, EIM demonstrates applicability in both pre-clinical and clinical settings and can be used as a safe, non-invasive, and longitudinal proxy biomarker to assess muscle health in DMD.
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Affiliation(s)
- Stephen M Chrzanowski
- Department of Neurology, Boston Children's Hospital, Boston, MA, USA.,Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Janice A Nagy
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Sarbesh Pandeya
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Seward B Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA
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11
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Nagy JA, Semple C, Lo P, Rutkove SB. Assessing the therapeutic impact of resveratrol in ALS SOD1-G93A mice with electrical impedance myography. Front Neurol 2022; 13:1059743. [PMID: 36619925 PMCID: PMC9813785 DOI: 10.3389/fneur.2022.1059743] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 12/07/2022] [Indexed: 12/24/2022] Open
Abstract
To aid in the identification of new treatments for amyotrophic lateral sclerosis (ALS), convenient biomarkers are needed to effectively and uniformly measure drug efficacy. To this end, we assessed the effects of the nutraceutical resveratrol (RSV) on disease onset and overall survival in SOD1-G93A (ALS) mice and compared several standard biomarkers including body mass, motor score (MS), paw grip endurance (PGE), and compound motor action potential (CMAP) amplitude, with the technique of electrical impedance myography (EIM) to follow disease progression. Eighteen ALS mice (nine females, nine males) received RSV in the chow (dose: 120 mg/kg/day) starting at 8 weeks of age; 19 ALS mice (nine females, 10 males) received normal chow; 10 wild type (WT) littermates (five females, five males) fed standard chow served as controls. Biomarker assessments were performed weekly beginning at 8 weeks. No differences in either disease onset or overall survival were found between RSV-treated and untreated ALS mice of either sex; moreover, all biomarkers failed to identify any beneficial effect of RSV when administered at this dose. Therefore, for the comparative evaluation of the ability of the various biomarkers to detect the earliest symptoms of disease, data from all animals (i.e., RSV-treated and untreated ALS mice of both sexes) were combined. Of the biomarkers tested, EIM impedance values, i.e., surface EIM longitudinal phase at 50 kHz (LP 50 kHz), and CMAP amplitude showed the earliest significant changes from baseline. LP 50 kHz values showed a rate of decline equivalent to that of CMAP amplitude and correlated with both PGE and CMAP amplitude [Spearman rho = 0.806 (p = 0.004) and 0.627 (p = 0.044), respectively]. Consistent with previous work, these findings indicate that surface EIM can serve as an effective non-invasive biomarker for preclinical drug testing in rodent models of ALS.
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12
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Farid A, Golden E, Robicheau S, Hu A, Cheung K, Yu PB, Rutkove SB, Upadhyay J. Diminished muscle integrity in patients with fibrodysplasia ossificans progressiva assessed with at-home electrical impedance myography. Sci Rep 2022; 12:20908. [PMID: 36463382 PMCID: PMC9719538 DOI: 10.1038/s41598-022-25610-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Accepted: 12/01/2022] [Indexed: 12/05/2022] Open
Abstract
Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare disorder involving skeletal dysplasia and heterotopic ossification (HO) of muscle and connective tissue. We aimed to define a novel biomarker in FOP that enables reliable assessment of musculoskeletal tissue integrity. Considering logistical difficulties that FOP patients often face, our goal was to identify an at-home biomarker technique. Electrical impedance myography (EIM) is a non-invasive, portable method that can inform on muscle health. 15 FOP patients (age 10-52) and 13 healthy controls were assessed. Using EIM, multiple muscle groups were characterized per participant in a 45-min period. The Cumulative Analogue Joint Involvement Scale (CAJIS) was implemented to determine mobility burden severity. We additionally evaluated physical activity levels via a Patient-Reported Outcomes Measurement Information System (PROMIS)-based questionnaire. Relative to controls, FOP patients demonstrated significantly lower regional and whole-body phase values at 50 kHz and 100 kHz, indicating more diseased muscle tissue. Lower whole-body phase and reactance values, and higher resistance values, were associated with greater FOP burden (CAJIS score range: 4-30) and lower physical activity levels at 50 kHz and 100 kHz. This study points to the potential utility of EIM as a clinical biomarker tool capable of characterizing muscle integrity in FOP.
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Affiliation(s)
- Alexander Farid
- grid.38142.3c000000041936754XDepartment of Anesthesiology, Critical Care and Pain Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115 USA
| | - Emma Golden
- grid.38142.3c000000041936754XDepartment of Anesthesiology, Critical Care and Pain Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115 USA
| | | | - Alice Hu
- grid.492584.6Myolex Inc, Boston, MA USA
| | - Kin Cheung
- BioSAS Consulting, Inc., Wellesley, MA USA
| | - Paul B. Yu
- grid.38142.3c000000041936754XDivision of Cardiology, Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Seward B. Rutkove
- grid.239395.70000 0000 9011 8547Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA USA
| | - Jaymin Upadhyay
- grid.38142.3c000000041936754XDepartment of Anesthesiology, Critical Care and Pain Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115 USA ,grid.38142.3c000000041936754XDepartment of Psychiatry, McLean Hospital, Harvard Medical School, Belmont, MA, USA
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13
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Pandeya SR, Nagy JA, Riveros D, Semple C, Taylor RS, Hu A, Sanchez B, Rutkove SB. Using machine learning algorithms to enhance the diagnostic performance of electrical impedance myography. Muscle Nerve 2022; 66:354-361. [PMID: 35727064 DOI: 10.1002/mus.27664] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 04/23/2022] [Accepted: 06/14/2022] [Indexed: 11/11/2022]
Abstract
INTRODUCTION/AIMS We assessed the classification performance of machine learning (ML) using multifrequency electrical impedance myography (EIM) values to improve upon diagnostic outcomes as compared to those based on a single EIM value. METHODS EIM data was obtained from unilateral excised gastrocnemius in eighty diseased mice (26 D2-mdx, Duchenne muscular dystrophy model, 39 SOD1G93A ALS model, and 15 db/db, a model of obesity-induced muscle atrophy) and 33 wild-type (WT) animals. We assessed the classification performance of a ML random forest algorithm incorporating all the data (multifrequency resistance, reactance and phase values) comparing it to the 50 kHz phase value alone. RESULTS ML outperformed the 50 kHz analysis as based on receiver-operating characteristic curves and measurement of the area under the curve (AUC). For example, comparing all diseases together versus WT from the test set outputs, the AUC was 0.52 for 50 kHz phase, but was 0.94 for the ML model. Similarly, when comparing ALS versus WT, the AUCs were 0.79 for 50 kHz phase and 0.99 for ML. DISCUSSION Multifrequency EIM utilizing ML improves upon classification compared to that achieved with a single-frequency value. ML approaches should be considered in all future basic and clinical diagnostic applications of EIM.
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Affiliation(s)
- Sarbesh R Pandeya
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, USA
| | - Janice A Nagy
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, USA
| | - Daniela Riveros
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, USA
| | - Carson Semple
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, USA
| | - Rebecca S Taylor
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, USA
| | | | - Benjamin Sanchez
- Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah
| | - Seward B Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, USA
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14
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Kowal JB, Verga SA, Pandeya SR, Cochran RJ, Sabol JC, Rutkove SB, Coates JR. Electrical Impedance Myography in Dogs With Degenerative Myelopathy. Front Vet Sci 2022; 9:874277. [PMID: 35711791 PMCID: PMC9196121 DOI: 10.3389/fvets.2022.874277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 04/20/2022] [Indexed: 11/13/2022] Open
Abstract
Canine degenerative myelopathy (DM) leads to disuse and neurogenic muscle atrophy. Currently there is a lack of non-invasive quantitative measures of muscle health in dogs with DM. Muscle pathology has been previously quantified in other disorders using the technique of electrical impedance myography (EIM) but it has not been reported for DM. The objective of this study was to compare EIM between DM-affected and similar aged healthy dogs as well as assess EIM changes over time in DM-affected dogs. Multifrequency EIM was performed on DM affected dogs at baseline and during disease progression and on age-matched healthy dogs. Muscles evaluated in the pelvic limbs included the craniotibialis, gastrocnemius, gracilis, sartorius, and biceps femoris. The 100 kHz phase angle was extracted from the full frequency set for analysis. Phase values were lower in DM dogs as compared to healthy controls. Specifically, phase of the gastrocnemius was lower on the left (θ = 7.69, 13.06; p =0.002) and right (θ= 6.11, 11.72; p = 0.001) in DM vs. control dogs, respectively. The mean phase value of all measured muscles was also lower on the left (θ = 9.24, 11.62; p = 0.012) and right (θ = 9.18, 11.72; p = 0.021). Other individual muscles measured did not reach statistical significance, although values were consistently lower in DM-affected dogs. With disease progression, downward trends in phase values were detected in DM-affected dogs when monitored serially over time. This study demonstrates that EIM 100 kHz phase values are sensitive to muscle pathology in DM and that phase values are decreased in dogs with DM. Measurements from the gastrocnemius muscle show the greatest differences from similar aged healthy dogs suggesting it may be the preferred muscle for future EIM studies.
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Affiliation(s)
- Joseph B. Kowal
- Department of Veterinary Medicine and Surgery, University of Missouri, College of Veterinary Medicine, Columbia, MO, United States
- *Correspondence: Joseph B. Kowal
| | - Sarah A. Verga
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Sarbesh R. Pandeya
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Randall J. Cochran
- Department of Veterinary Medicine and Surgery, University of Missouri, College of Veterinary Medicine, Columbia, MO, United States
| | - Julianna C. Sabol
- Department of Veterinary Medicine and Surgery, University of Missouri, College of Veterinary Medicine, Columbia, MO, United States
| | - Seward B. Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Joan R. Coates
- Department of Veterinary Medicine and Surgery, University of Missouri, College of Veterinary Medicine, Columbia, MO, United States
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15
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Cheng KS, Su YL, Kuo LC, Yang TH, Lee CL, Chen W, Liu SH. Muscle Mass Measurement Using Machine Learning Algorithms with Electrical Impedance Myography. SENSORS 2022; 22:s22083087. [PMID: 35459072 PMCID: PMC9031580 DOI: 10.3390/s22083087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 04/15/2022] [Accepted: 04/16/2022] [Indexed: 02/04/2023]
Abstract
Sarcopenia is a wild chronic disease among elderly people. Although it does not entail a life-threatening risk, it will increase the adverse risk due to the associated unsteady gait, fall, fractures, and functional disability. The import factors in diagnosing sarcopenia are muscle mass and strength. The examination of muscle mass must be carried in the clinic. However, the loss of muscle mass can be improved by rehabilitation that can be performed in non-medical environments. Electronic impedance myography (EIM) can measure some parameters of muscles that have the correlations with muscle mass and strength. The goal of this study is to use machine learning algorithms to estimate the total mass of thigh muscles (MoTM) with the parameters of EIM and body information. We explored the seven major muscles of lower limbs. The feature selection methods, including recursive feature elimination (RFE) and feature combination, were used to select the optimal features based on the ridge regression (RR) and support vector regression (SVR) models. The optimal features were the resistance of rectus femoris normalized by the thigh circumference, phase of tibialis anterior combined with the gender, and body information, height, and weight. There were 96 subjects involved in this study. The performances of estimating the MoTM used the regression coefficient (r2) and root-mean-square error (RMSE), which were 0.800 and 0.929, and 1.432 kg and 0.980 kg for RR and SVR models, respectively. Thus, the proposed method could have the potential to support people examining their muscle mass in non-medical environments.
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Affiliation(s)
- Kuo-Sheng Cheng
- Department of Biomedical Engineering, National Cheng Kung University, Tainai 701, Taiwan; (K.-S.C.); (Y.-L.S.); (T.-H.Y.)
| | - Ya-Ling Su
- Department of Biomedical Engineering, National Cheng Kung University, Tainai 701, Taiwan; (K.-S.C.); (Y.-L.S.); (T.-H.Y.)
| | - Li-Chieh Kuo
- Department of Occupational Therapy, National Cheng Kung University, Tainan 701, Taiwan;
| | - Tai-Hua Yang
- Department of Biomedical Engineering, National Cheng Kung University, Tainai 701, Taiwan; (K.-S.C.); (Y.-L.S.); (T.-H.Y.)
| | - Chia-Lin Lee
- Department of Physical Education, National Kaohsiung Normal University, Kaohsiung City 80201, Taiwan;
| | - Wenxi Chen
- Biomedical Information Engineering Laboratory, The University of Aizu, Aizu-Wakamatsu City, Fukushima 965-8580, Japan;
| | - Shing-Hong Liu
- Department of Computer Science and Information Engineering, Chaoyang University of Technology, Taichung 413310, Taiwan
- Correspondence: ; Tel.: +886-4-233230000-7811
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16
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Sato H, Nakamura T. Evaluation of Skeletal Muscle Dysfunction Associated With Acute Inflammation by Electrical Impedance Myography: A Case Report on Skeletal Muscle Dysfunction After Cardiac Surgery and Literature Review. Cureus 2021; 13:e20166. [PMID: 34881132 PMCID: PMC8643273 DOI: 10.7759/cureus.20166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/04/2021] [Indexed: 11/30/2022] Open
Abstract
Electrical impedance myography (EIM) is an evaluation technique for skeletal muscles that uses electrical impedance technology. Recent reviews have shown that EIM is useful as a method to assess changes in skeletal muscle quality and quantity with aging. These may be utilized for functional changes in inflammatory skeletal muscles, such as disease and operation. In this report, the impedance parameters using EIM present perioperative skeletal muscle changes in patients after cardiac surgery. In addition, we will describe the efficacy of EIM in skeletal muscle dysfunction due to inflammation or disease. This study aimed to elucidate the efficacy of EIM in acute inflammation-associated skeletal muscle dysfunction.
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Affiliation(s)
- Hiroki Sato
- Department of Radiological Technology, Graduate School of Health Sciences, Okayama University, Okayama, JPN.,Department of Rehabilitation Medicine, Kawasaki Medical School, Kurashiki, JPN.,Department of Rehabilitation Center, Kawasaki Medical School Hospital, Kurashiki, JPN
| | - Takao Nakamura
- Graduate School of Health Sciences, Okayama University, Okayama, JPN
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17
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Schooling CN, Jamie Healey T, McDonough HE, French SJ, McDermott CJ, Shaw PJ, Kadirkamanathan V, Alix JJP. Tensor electrical impedance myography identifies clinically relevant features in amyotrophic lateral sclerosis. Physiol Meas 2021; 42. [PMID: 34521070 DOI: 10.1088/1361-6579/ac2672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 09/14/2021] [Indexed: 11/12/2022]
Abstract
Objective.Electrical impedance myography (EIM) shows promise as an effective biomarker in amyotrophic lateral sclerosis (ALS). EIM applies multiple input frequencies to characterise muscle properties, often via multiple electrode configurations. Herein, we assess if non-negative tensor factorisation (NTF) can provide a framework for identifying clinically relevant features within a high dimensional EIM dataset.Approach.EIM data were recorded from the tongue of healthy and ALS diseased individuals. Resistivity and reactivity measurements were made for 14 frequencies, in three electrode configurations. This gives 84 (2 × 14 × 3) distinct data points per participant. NTF was applied to the dataset for dimensionality reduction, termed tensor EIM. Significance tests, symptom correlation and classification approaches were explored to compare NTF to using all raw data and feature selection.Main Results.Tensor EIM provides highly significant differentiation between healthy and ALS patients (p< 0.001, AUROC = 0.78). Similarly tensor EIM differentiates between mild and severe disease states (p< 0.001, AUROC = 0.75) and significantly correlates with symptoms (ρ= 0.7,p< 0.001). A trend of centre frequency shifting to the right was identified in diseased spectra, which is in line with the electrical changes expected following muscle atrophy.Significance.Tensor EIM provides clinically relevant metrics for identifying ALS-related muscle disease. This procedure has the advantage of using the whole spectral dataset, with reduced risk of overfitting. The process identifies spectral shapes specific to disease allowing for a deeper clinical interpretation.
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Affiliation(s)
- Chlöe N Schooling
- Sheffield Institute for Translational Neuroscience, University of Sheffield, United Kingdom.,Department of Automatic Control and Systems Engineering, University of Sheffield, United Kingdom
| | - T Jamie Healey
- Department of Clinical Engineering, Sheffield Teaching Hospitals NHS Foundation Trust, United Kingdom
| | - Harry E McDonough
- Sheffield Institute for Translational Neuroscience, University of Sheffield, United Kingdom
| | - Sophie J French
- Sheffield Institute for Translational Neuroscience, University of Sheffield, United Kingdom
| | | | - Pamela J Shaw
- Sheffield Institute for Translational Neuroscience, University of Sheffield, United Kingdom
| | - Visakan Kadirkamanathan
- Department of Automatic Control and Systems Engineering, University of Sheffield, United Kingdom
| | - James J P Alix
- Sheffield Institute for Translational Neuroscience, University of Sheffield, United Kingdom
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18
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Pandeya SR, Nagy JA, Riveros D, Semple C, Taylor RS, Sanchez B, Rutkove SB. Relationships between in vivo surface and ex vivo electrical impedance myography measurements in three different neuromuscular disorder mouse models. PLoS One 2021; 16:e0259071. [PMID: 34714853 PMCID: PMC8555802 DOI: 10.1371/journal.pone.0259071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 10/11/2021] [Indexed: 11/18/2022] Open
Abstract
Electrical impedance myography (EIM) using surface techniques has shown promise as a means of diagnosing and tracking disorders affecting muscle and assessing treatment efficacy. However, the relationship between such surface-obtained impedance values and pure muscle impedance values has not been established. Here we studied three groups of diseased and wild-type (WT) animals, including a Duchenne muscular dystrophy model (the D2-mdx mouse), an amyotrophic lateral sclerosis (ALS) model (the SOD1 G93A mouse), and a model of fat-related atrophy (the db/db diabetic obese mouse), performing hind limb measurements using a standard surface array and ex vivo measurements on freshly excised gastrocnemius muscle. A total of 101 animals (23 D2-mdx, 43 ALS mice, 12 db/db mice, and corresponding 30 WT mice) were studied with EIM across a frequency range of 8 kHz to 1 MHz. For both D2-mdx and ALS models, moderate strength correlations (Spearman rho values generally ranging from 0.3-0.7, depending on the impedance parameter (i.e., resistance, reactance and phase) were obtained. In these groups of animals, there was an offset in frequency with impedance values obtained at higher surface frequencies correlating more strongly to impedance values obtained at lower ex vivo frequencies. For the db/db model, correlations were comparatively weaker and strongest at very high and very low frequencies. When combining impedance data from all three disease models together, moderate correlations persisted (with maximal Spearman rho values of 0.45). These data support that surface EIM data reflect ex vivo muscle tissue EIM values to a moderate degree across several different diseases, with the highest correlations occurring in the 10-200 kHz frequency range. Understanding these relationships will prove useful for future applications of the technique of EIM in the assessment of neuromuscular disorders.
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Affiliation(s)
- Sarbesh R. Pandeya
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States of America
| | - Janice A. Nagy
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States of America
| | - Daniela Riveros
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States of America
| | - Carson Semple
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States of America
| | - Rebecca S. Taylor
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States of America
| | - Benjamin Sanchez
- Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah, United States of America
| | - Seward B. Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States of America
- * E-mail:
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19
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Pandeya SR, Nagy JA, Riveros D, Semple C, Taylor RS, Mortreux M, Sanchez B, Kapur K, Rutkove SB. Estimating myofiber cross-sectional area and connective tissue deposition with electrical impedance myography: A study in D2-mdx mice. Muscle Nerve 2021; 63:941-950. [PMID: 33759456 PMCID: PMC8883327 DOI: 10.1002/mus.27240] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 03/19/2021] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Surface electrical impedance myography (sEIM) has the potential for providing information on muscle composition and structure noninvasively. We sought to evaluate its use to predict myofiber size and connective tissue deposition in the D2-mdx model of Duchenne muscular dystrophy (DMD). METHODS We applied a prediction algorithm, the least absolute shrinkage and selection operator, to select specific EIM measurements obtained with surface and ex vivo EIM data from D2-mdx and wild-type (WT) mice (analyzed together or separately). We assessed myofiber cross-sectional area histologically and hydroxyproline (HP), a surrogate measure for connective tissue content, biochemically. RESULTS Using WT and D2-mdx impedance values together in the algorithm, sEIM gave average root-mean-square errors (RMSEs) of 26.6% for CSA and 45.8% for HP, which translate into mean errors of ±363 μm2 for a mean CSA of 1365 μm2 and of ±1.44 μg HP/mg muscle for a mean HP content of 3.15 μg HP/mg muscle. Stronger predictions were obtained by analyzing sEIM data from D2-mdx animals alone (RMSEs of 15.3% for CSA and 34.1% for HP content). Predictions made using ex vivo EIM data from D2-mdx animals alone were nearly equivalent to those obtained with sEIM data (RMSE of 16.59% for CSA), and slightly more accurate for HP (RMSE of 26.7%). DISCUSSION Surface EIM combined with a predictive algorithm can provide estimates of muscle pathology comparable to values obtained using ex vivo EIM, and can be used as a surrogate measure of disease severity and progression and response to therapy.
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Affiliation(s)
- Sarbesh R. Pandeya
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Janice A. Nagy
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Daniela Riveros
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Carson Semple
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Rebecca S. Taylor
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Marie Mortreux
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Benjamin Sanchez
- Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah
| | - Kush Kapur
- Department of Neurology, Boston Childrenʼs Hospital, Harvard Medical School, Boston, Massachusetts
| | - Seward B. Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
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20
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Clark BC, Rutkove S, Lupton EC, Padilla CJ, Arnold WD. Potential Utility of Electrical Impedance Myography in Evaluating Age-Related Skeletal Muscle Function Deficits. Front Physiol 2021; 12:666964. [PMID: 34025454 PMCID: PMC8138591 DOI: 10.3389/fphys.2021.666964] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 04/13/2021] [Indexed: 12/19/2022] Open
Abstract
Skeletal muscle function deficits associated with advancing age are due to several physiological and morphological changes including loss of muscle size and quality (conceptualized as a reduction in the intrinsic force-generating capacity of a muscle when adjusted for muscle size). Several factors can contribute to loss of muscle quality, including denervation, excitation-contraction uncoupling, increased fibrosis, and myosteatosis (excessive levels of inter- and intramuscular adipose tissue and intramyocellular lipids). These factors also adversely affect metabolic function. There is a major unmet need for tools to rapidly and easily assess muscle mass and quality in clinical settings with minimal patient and provider burden. Herein, we discuss the potential for electrical impedance myography (EIM) as a tool to evaluate muscle mass and quality in older adults. EIM applies weak, non-detectible (e.g., 400 μA), mutifrequency (e.g., 1 kHz–1 MHz) electrical currents to a muscle (or muscle group) through two excitation electrodes, and resulting voltages are measured via two sense electrodes. Measurements are fast (~5 s/muscle), simple to perform, and unaffected by factors such as hydration that may affect other simple measures of muscle status. After nearly 2 decades of study, EIM has been shown to reflect muscle health status, including the presence of atrophy, fibrosis, and fatty infiltration, in a variety of conditions (e.g., developmental growth and maturation, conditioning/deconditioning, and obesity) and neuromuscular diseases states [e.g., amyotrophic lateral sclerosis (ALS) and muscular dystrophies]. In this article, we describe prior work and current evidence of EIM’s potential utility as a measure of muscle health in aging and geriatric medicine.
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Affiliation(s)
- Brian C Clark
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, Athens, OH, United States.,Department of Biomedical Sciences, Ohio University, Athens, OH, United States.,Division of Geriatric Medicine, Ohio University, Athens, OH, United States
| | - Seward Rutkove
- Department of Neurology, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA, United States
| | | | - Carlos J Padilla
- Department of Neurology, Ohio State University, Columbus, OH, United States
| | - W David Arnold
- Department of Neurology, Ohio State University, Columbus, OH, United States
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21
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Sanchez B, Martinsen OG, Freeborn TJ, Furse CM. Electrical impedance myography: A critical review and outlook. Clin Neurophysiol 2020; 132:338-344. [PMID: 33450556 DOI: 10.1016/j.clinph.2020.11.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 10/31/2020] [Accepted: 11/18/2020] [Indexed: 12/30/2022]
Abstract
Electrical impedance myography (EIM) technology is finding application in neuromuscular disease research as a tool to assess muscle health. Correlations between EIM outcomes, functional, imaging and histological data have been established in a variety of neuromuscular disorders; however, an analytical discussion of EIM is lacking. This review presents an explanation for clinicians and others who are applying EIM and interpreting impedance outcomes. The background of EIM is presented, including the relation between EIM, volume conduction properties, tissue structure, electrode configuration and conductor volume. Also discussed are technical considerations to guide the reader to critically evaluate EIM and understand its limitations and strengths.
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Affiliation(s)
- Benjamin Sanchez
- Sanchez Research Lab, Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USA.
| | - Orjan G Martinsen
- Department of Physics, University of Oslo, 0371 Oslo, Norway; Department of Clinical and Biomedical Engineering, Oslo University Hospital, Oslo 0372, Norway
| | - Todd J Freeborn
- Department of Electrical and Computer Engineering, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Cynthia M Furse
- Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USA
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22
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Antisense oligonucleotide and adjuvant exercise therapy reverse fatigue in old mice with myotonic dystrophy. MOLECULAR THERAPY. NUCLEIC ACIDS 2020; 23:393-405. [PMID: 33473325 PMCID: PMC7787993 DOI: 10.1016/j.omtn.2020.11.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 11/17/2020] [Indexed: 02/06/2023]
Abstract
Patients with myotonic dystrophy type 1 (DM1) identify chronic fatigue as the most debilitating symptom, which manifests in part as prolonged recovery after exercise. Clinical features of DM1 result from pathogenic gain-of-function activity of transcripts containing an expanded microsatellite CUG repeat (CUGexp). In DM1 mice, therapies targeting the CUGexp transcripts correct the molecular phenotype, reverse myotonia, and improve muscle pathology. However, the effect of targeted molecular therapies on fatigue in DM1 is unknown. Here, we use two mouse models of DM1, age-matched wild-type controls, an exercise-activity assay, electrical impedance myography, and therapeutic antisense oligonucleotides (ASOs) to show that exaggerated exercise-induced fatigue progresses with age, is unrelated to muscle fiber size, and persists despite correction of the molecular phenotype for 3 months. In old DM1 mice, ASO treatment combined with an exercise training regimen consisting of treadmill walking 30 min per day 6 days per week for 3 months reverse all measures of fatigue. Exercise training without ASO therapy improves some measures of fatigue without correction of the molecular pathology. Our results highlight a key limitation of ASO monotherapy for this clinically important feature and support the development of moderate-intensity exercise as an adjuvant for targeted molecular therapies of DM1.
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23
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Semple C, Riveros D, Sung DM, Nagy JA, Rutkove SB, Mortreux M. Using Electrical Impedance Myography as a Biomarker of Muscle Deconditioning in Rats Exposed to Micro- and Partial-Gravity Analogs. Front Physiol 2020; 11:557796. [PMID: 33041858 PMCID: PMC7522465 DOI: 10.3389/fphys.2020.557796] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 08/25/2020] [Indexed: 12/12/2022] Open
Abstract
As astronauts prepare to undertake new extra-terrestrial missions, innovative diagnostic tools are needed to better assess muscle deconditioning during periods of weightlessness and partial gravity. Electrical impedance myography (EIM) has been used to detect muscle deconditioning in rodents exposed to microgravity during spaceflight or using the standard ground-based model of hindlimb unloading via tail suspension (HU). Here, we used EIM to assess muscle changes in animals exposed to two new models: hindlimb suspension using a pelvic harness (HLS) and a partial weight-bearing (PWB) model that mimics partial gravity (including Lunar and Martian gravities). We also used a simple needle array electrode in lieu of surface or ex vivo EIM approaches previously employed. Our HLS results confirmed earlier findings obtained after spaceflight and tail suspension. Indeed, one EIM measure (i.e., phase-slope) that was previously reported as highly sensitive, was significantly decreased after HLS (day 0: 14.60 ± 0.97, day 7: 11.03 ± 0.81, and day 14: 10.13 ± 0.55 | Deg/MHz|, p < 0.0001), and was associated with a significant decrease in muscle grip force. Although EIM parameters such as 50 kHz phase, reactance, and resistance remained variable over 14 days in PWB animals, we identified major PWB-dependent effects at 7 days. Moreover, the data at both 7 and 14 days correlated to previously observed changes in rear paw grip force using the same PWB model. In conclusion, our data suggest that EIM has the potential to serve as biomarker of muscle deconditioning during exposure to both micro- and partial- gravity during future human space exploration.
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Affiliation(s)
- Carson Semple
- Department of Neurology, Harvard Medical School - Beth Israel Deaconess Medical Center, Boston, MA, United States
| | - Daniela Riveros
- Department of Neurology, Harvard Medical School - Beth Israel Deaconess Medical Center, Boston, MA, United States
| | - Dong-Min Sung
- Department of Neurology, Harvard Medical School - Beth Israel Deaconess Medical Center, Boston, MA, United States
| | - Janice A Nagy
- Department of Neurology, Harvard Medical School - Beth Israel Deaconess Medical Center, Boston, MA, United States
| | - Seward B Rutkove
- Department of Neurology, Harvard Medical School - Beth Israel Deaconess Medical Center, Boston, MA, United States
| | - Marie Mortreux
- Department of Neurology, Harvard Medical School - Beth Israel Deaconess Medical Center, Boston, MA, United States
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24
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Semple C, Riveros D, Nagy JA, Rutkove SB, Mortreux M. Partial Weight-Bearing in Female Rats: Proof of Concept in a Martian-Gravity Analog. Front Physiol 2020; 11:302. [PMID: 32308630 PMCID: PMC7145975 DOI: 10.3389/fphys.2020.00302] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 03/17/2020] [Indexed: 12/13/2022] Open
Abstract
Many studies have investigated the physiological response to microgravity in both astronauts and animals. However, while space agencies have sought to deploy more women on their missions; animal models rarely include females studies or comparisons between males and females. Therefore, we exposed adult female rats to 2 weeks of partial weight-bearing at either 100% of their normal loading (PWB100) or 40% of their normal loading (PWB40), corresponding to Martian gravity-analog, and assess muscle function, force and histomorphometry. Females exposed to PWB showed an 11.62% decline in hindlimb grip force associated with an 11.84% decrease in soleus myofiber size after 14 days of exposure, while maintaining normal blood oxygenation and stress levels. This pilot study represents the first experiment designed to understand the muscular disuse associated with a partial reduction in mechanical loading in female rats, and the first step needed to develop successful mitigating strategies. NEW AND NOTEWORTHY This research article describes the first use of quadrupedal partial weight-bearing in female rats. This study demonstrates the feasibility of partial gravity analogs in females and allows for future investigations about the impact of sex on muscle deconditioning due to reduced mechanical loading.
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Affiliation(s)
- Carson Semple
- Harvard Medical School – Beth Israel Deaconess Medical Center, Department of Neurology, Boston, MA, United States
| | - Daniela Riveros
- Harvard Medical School – Beth Israel Deaconess Medical Center, Department of Neurology, Boston, MA, United States
| | - Janice A. Nagy
- Harvard Medical School – Beth Israel Deaconess Medical Center, Department of Neurology, Boston, MA, United States
| | - Seward B. Rutkove
- Harvard Medical School – Beth Israel Deaconess Medical Center, Department of Neurology, Boston, MA, United States
| | - Marie Mortreux
- Harvard Medical School – Beth Israel Deaconess Medical Center, Department of Neurology, Boston, MA, United States
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25
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Rutkove SB. Electrical impedance myography: MRI-like data without the need for MRI. Muscle Nerve 2020; 61:554-556. [PMID: 32052459 DOI: 10.1002/mus.26832] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 02/03/2020] [Accepted: 02/09/2020] [Indexed: 11/11/2022]
Affiliation(s)
- Seward B Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts
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26
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Accorsi A, Cramer ML, Girgenrath M. Fibrogenesis in LAMA2-Related Muscular Dystrophy Is a Central Tenet of Disease Etiology. Front Mol Neurosci 2020; 13:3. [PMID: 32116541 PMCID: PMC7010923 DOI: 10.3389/fnmol.2020.00003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 01/07/2020] [Indexed: 12/12/2022] Open
Abstract
LAMA2-related congenital muscular dystrophy, also known as MDC1A, is caused by loss-of-function mutations in the alpha2 chain of Laminin-211. Loss of this protein interrupts the connection between the muscle cell and its extracellular environment and results in an aggressive, congenital-onset muscular dystrophy characterized by severe hypotonia, lack of independent ambulation, and early mortality driven by respiratory complications and/or failure to thrive. Of the pathomechanisms of MDC1A, the earliest and most prominent is widespread and rampant fibrosis. Here, we will discuss some of the key drivers of fibrosis including TGF-beta and renin–angiotensin system signaling and consequences of these pathways including myofibroblast transdifferentiation and matrix remodeling. We will also highlight some of the differences in fibrogenesis in congenital muscular dystrophy (CMD) with that seen in Duchenne muscular dystrophy (DMD). Finally, we will connect the key signaling pathways in the pathogenesis of MDC1A to the current status of the therapeutic approaches that have been tested in the preclinical models of MDC1A to treat fibrosis.
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Affiliation(s)
| | - Megan L Cramer
- Rare Disease Research Unit, Pfizer Inc., Cambridge, MA, United States
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27
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Alix JJP, McDonough HE, Sonbas B, French SJ, Rao DG, Kadirkamanathan V, McDermott CJ, Healey TJ, Shaw PJ. Multi-dimensional electrical impedance myography of the tongue as a potential biomarker for amyotrophic lateral sclerosis. Clin Neurophysiol 2020; 131:799-808. [PMID: 32066098 DOI: 10.1016/j.clinph.2019.12.418] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 12/09/2019] [Accepted: 12/15/2019] [Indexed: 12/11/2022]
Abstract
OBJECTIVE In amyotrophic lateral sclerosis (ALS) bulbar disease biomarkers are lacking. We evaluated a novel tongue electrical impedance myography (EIM) system, utilising both 2D and 3D electrode configurations for detection of tongue pathology. METHODS Longitudinal multi-frequency phase angle spectra were recorded from 41 patients with ALS (baseline, 3 and 6 months) and 30 healthy volunteers (baseline and 6 months). ALS functional rating scale-revised (ALSFRS-R) data and quantitative tongue strength measurements were collected. EIM data were analysed for reliability (intra-class correlation coefficient; ICC) and differences between patients and volunteers ascertained using both univariate (Mann-Whitney U test) and multivariate techniques (feature selection and L2 norm). RESULTS The device produced highly reliable data (pooled ICC: 0.836). Significant EIM differences were apparent between ALS patients and healthy volunteers (P < 0.001). EIM data demonstrated a significant relationship to tongue strength and bulbar ALSFRS-R scores (P < 0.015). The EIM recordings revealed a group level longitudinal change over 6 months and consistently identified patients in whom symptoms or tongue strength changed. CONCLUSIONS The novel EIM tongue system produces reliable data and can differentiate between healthy muscle and ALS-related disease. SIGNIFICANCE Tongue EIM utilising multiple frequencies and electrode configurations has potential as a bulbar disease biomarker in ALS.
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Affiliation(s)
- James J P Alix
- Sheffield Institute for Translational Neuroscience, University of Sheffield, UK; Department of Clinical Neurophysiology, Sheffield Teaching Hospitals NHS Foundation Trust, UK.
| | - Harry E McDonough
- Sheffield Institute for Translational Neuroscience, University of Sheffield, UK
| | - Buket Sonbas
- Department of Automatic Control and Systems Engineering, University of Sheffield
| | - Sophie J French
- Sheffield Institute for Translational Neuroscience, University of Sheffield, UK
| | - D Ganesh Rao
- Department of Clinical Neurophysiology, Sheffield Teaching Hospitals NHS Foundation Trust, UK
| | | | - Christopher J McDermott
- Sheffield Institute for Translational Neuroscience, University of Sheffield, UK; Department of Neurology, Sheffield Teaching Hospitals NHS Foundation Trust, UK
| | - T Jamie Healey
- Department of Clinical Engineering, Sheffield Teaching Hospitals NHS Foundation Trust, UK
| | - Pamela J Shaw
- Sheffield Institute for Translational Neuroscience, University of Sheffield, UK; Department of Neurology, Sheffield Teaching Hospitals NHS Foundation Trust, UK
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28
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Hamel J, Lee P, Glenn MD, Burka T, Choi IY, Friedman SD, Shaw DWW, McCalley A, Herbelin L, Dimachkie MM, Lemmers R, van der Maarel SM, Barohn RJ, Tawil R, Statland JM. Magnetic resonance imaging correlates with electrical impedance myography in facioscapulohumeral muscular dystrophy. Muscle Nerve 2020; 61:644-649. [PMID: 31884698 DOI: 10.1002/mus.26792] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 12/16/2019] [Accepted: 12/21/2019] [Indexed: 12/25/2022]
Abstract
INTRODUCTION Electrical impedance myography (EIM) has been proposed as a noninvasive biomarker of muscle composition in facioscapulohumeral muscular dystrophy (FSHD). Here we determine the associations of EIM variables with muscle structure measured by MRI. METHODS We evaluated 20 patients with FSHD at two centers, comparing EIM measurements (resistance, reactance, and phase at 50, 100, and 211 kHZ) recorded from bilateral vastus lateralis, tibialis anterior, and medial gastrocnemius muscles to MRI skin and subcutaneous fat thickness, MRI T1-based muscle severity score (T1 muscle score), and MRI quantitative intramuscular Dixon fat fraction (FF). RESULTS While reactance and phase both correlated with FF and T1 muscle score, 50 kHz reactance was most sensitive to muscle structure alterations measured by both T1 score (ρ = -0.71, P < .001) and FF (ρ = -0.74, P < .001). DISCUSSION This study establishes the correlation of EIM with structural MRI features in FSHD and supports further evaluation of EIM as a potential biomarker in FSHD clinical trials.
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Affiliation(s)
- Johanna Hamel
- Department of Neurology, University of Rochester Medical Center, Rochester, New York
| | - Phil Lee
- Department of Radiology, University of Kansas Medical Center, Kansas City, Kansas.,Hoglund Brain Imaging Center, University of Kansas Medical Center, Kansas City, Kansas
| | - Melanie D Glenn
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas
| | - Tekalign Burka
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas
| | - In-Young Choi
- Hoglund Brain Imaging Center, University of Kansas Medical Center, Kansas City, Kansas.,Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas
| | - Seth D Friedman
- Center for Clinical and Translational Research, Seattle Children's Hospital, Seattle, Washington
| | - Dennis W W Shaw
- Center for Clinical and Translational Research, Seattle Children's Hospital, Seattle, Washington
| | - Ayla McCalley
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas
| | - Laura Herbelin
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas
| | - Mazen M Dimachkie
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas
| | - Richard Lemmers
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Richard J Barohn
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas
| | - Rabi Tawil
- Department of Neurology, University of Rochester Medical Center, Rochester, New York
| | - Jeffrey M Statland
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas
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29
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Chrzanowski SM, Darras BT, Rutkove SB. The Value of Imaging and Composition-Based Biomarkers in Duchenne Muscular Dystrophy Clinical Trials. Neurotherapeutics 2020; 17:142-152. [PMID: 31879850 PMCID: PMC7007477 DOI: 10.1007/s13311-019-00825-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
As the drug development pipeline for Duchenne muscular dystrophy (DMD) rapidly advances, clinical trial outcomes need to be optimized. Effective assessment of disease burden, natural history progression, and response to therapy in clinical trials for Duchenne muscular dystrophy are critical factors for clinical trial success. By choosing optimal biomarkers to better assess therapeutic efficacy, study costs and sample size requirements can be reduced. Currently, functional measures continue to serve as the primary outcome for the majority of DMD clinical trials. Quantitative measures of muscle health, including magnetic resonance imaging and spectroscopy, electrical impedance myography, and ultrasound, sensitively identify diseased muscle, disease progression, and response to a therapeutic intervention. Furthermore, such non-invasive techniques have the potential to identify disease pathology prior to onset of clinical symptoms. Despite robust supportive evidence, non-invasive quantitative techniques are still not frequently utilized in clinical trials for Duchenne muscular dystrophy. Non-invasive quantitative techniques have demonstrated the ability to quantify disease progression and potential response to therapeutic intervention, and should be used as a supplement to current standard functional measures. Such methods have the potential to significantly accelerate the development and approval of therapies for DMD.
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Affiliation(s)
- Stephen M Chrzanowski
- Department of Medicine, Boston Children's Hospital, 300 Longwood Ave., Boston, MA, 02115, USA.
| | - Basil T Darras
- Department of Neurology, Boston Children's Hospital, Boston, MA, USA
| | - Seward B Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA
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30
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Leitner ML, Kapur K, Darras BT, Yang M, Wong B, Dalle Pazze L, Florence J, Buck M, Freedman L, Bohorquez J, Rutkove S, Zaidman C. Electrical impedance myography for reducing sample size in Duchenne muscular dystrophy trials. Ann Clin Transl Neurol 2019; 7:4-14. [PMID: 31876124 PMCID: PMC6952321 DOI: 10.1002/acn3.50958] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 10/30/2019] [Accepted: 10/31/2019] [Indexed: 01/16/2023] Open
Abstract
Objective To evaluate the sensitivity of electrical impedance myography (EIM) to disease progression in both ambulatory and non‐ambulatory boys with DMD. Methods and Participants A non‐blinded, longitudinal cohort study of 29 ambulatory and 15 non‐ambulatory boys with DMD and age‐similar healthy boys. Subjects were followed for up to 1 year and assessed using the Myolex® mViewTM EIM system as part of a multicenter study. Results In the ambulatory group, EIM 100 kHz resistance values showed significant change compared to the healthy boys. For example, in lower extremity muscles, the average change in EIM 100 kHz resistance values over 12 months led to an estimated effect size of 1.58. Based on these results, 26 DMD patients/arm would be needed for a 12‐month clinical trial assuming a 50% treatment effect. In non‐ambulatory boys, EIM changes were greater in upper limb muscles. For example, biceps at 100kHz resistance gave an estimated effect size of 1.92 at 12 months. Based on these results, 18 non‐ambulatory DMD patients/arm would be needed for a 12‐month clinical trial assuming a 50% treatment effect. Longitudinal changes in the 100 kHz resistance values for the ambulatory boys correlated with the longitudinal changes in the timed supine‐to‐stand test. EIM was well‐tolerated throughout the study. Interpretation This study supports that EIM 100 kHz resistance is sensitive to DMD progression in both ambulatory and non‐ambulatory boys. Given the technology’s ease of use and broad age range of utility it should be employed as an exploratory endpoint in future clinical therapeutic trials in DMD. Trial Registration: Clincialtrials.gov registration #NCT02340923
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Affiliation(s)
| | - Kush Kapur
- Department of Neurology, Boston Children's Hospital, Boston, Massachusetts
| | - Basil T Darras
- Department of Neurology, Boston Children's Hospital, Boston, Massachusetts
| | - Michele Yang
- Department of Neurology, Children's Hospital Colorado, Denver, Colorado
| | - Brenda Wong
- Department of Pediatrics, University of Massachusetts Medical School, Worcester, Massachusetts
| | | | - Julaine Florence
- Department of Neurology, Washington University in St. Louis, St. Louis, Missouri
| | | | | | | | | | - Craig Zaidman
- Department of Neurology, Washington University in St. Louis, St. Louis, Missouri
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31
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Roy B, Rutkove SB, Nowak RJ. Electrical impedance myography as a biomarker of inclusion body myositis: A cross-sectional study. Clin Neurophysiol 2019; 131:368-371. [PMID: 31865137 DOI: 10.1016/j.clinph.2019.10.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 10/06/2019] [Accepted: 10/31/2019] [Indexed: 12/14/2022]
Abstract
OBJECTIVE To assess the value of electrical impedance myography (EIM) in inclusion body myositis (IBM). METHODS Patients with clinically defined IBM and healthy controls (HC) of similar age group were recruited. Each participant underwent manual muscle testing (MMT), 6-min walk test (6MWT), handgrip dynamometry, and IBM-functional rating scale assessment (IBM-FRS). EIM measurements were obtained from bilateral deltoid, biceps, forearm-flexors, quadriceps, tibialis anterior, and medial gastrocnemius. RESULTS Fourteen IBM patients and 12 HCs with mean age 68.6 ± 6 and 67.4 ± 5.4 years were included in the final analysis. Averaged phase value at 50 kHz (EIM50) and ratio of phase value at 50 kHz/200 kHz (EIMPR) from six-muscles were significantly lower in IBM patients when compared to HC (5.23 ± 1.34 vs 7.88 ± 1.9, p-value 0.002, and 0.55 ± 0.09 vs. 0.68 ± 0.09, p-value 0.004, respectively). A strong correlation was noted between IBM-FRS, 6MWT, disease-duration and the averaged value of EIM50 and EIMPR in the IBM patients (Spearman |rho|>0.7, p-values < 0.01). CONCLUSIONS EIM can differentiate between IBM patients and HCs and EIM parameters correlate with clinical outcome measures. SIGNIFICANCE EIM may be a potential objective biomarker for IBM. A longitudinal validation study is warranted.
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Affiliation(s)
- Bhaskar Roy
- Yale School of Medicine, Department of Neurology, 15 York Street, LCI 9, P.O. Box 208108, New Haven, CT 06519, USA.
| | - Seward B Rutkove
- Beth Israel Deaconess Medical Center, Department of Neurology, 330 Brookline Ave, Boston, MA 02215, USA.
| | - Richard J Nowak
- Yale School of Medicine, Department of Neurology, 15 York Street, LCI 9, P.O. Box 208108, New Haven, CT 06519, USA.
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32
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Mortreux M, Semple C, Riveros D, Nagy JA, Rutkove SB. Electrical impedance myography for the detection of muscle inflammation induced by λ-carrageenan. PLoS One 2019; 14:e0223265. [PMID: 31574117 PMCID: PMC6773213 DOI: 10.1371/journal.pone.0223265] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 09/17/2019] [Indexed: 12/13/2022] Open
Abstract
Electrical impedance myography (EIM) is a technique for the assessment of muscle health and composition and has been shown to be sensitive to a variety of muscle pathologies including neurogenic atrophy and connective tissue deposition. However, it has been minimally studied in pure inflammation. In this study, we sought to assess EIM sensitivity to experimental inflammation induced by the localized intramuscular injection of λ-carrageenan. A total of 91 mice underwent 1–1000 kHz EIM measurements of gastrocnemius using a needle array, followed by injection of either 0.3% λ-carrageenan in phosphate-buffered saline (PBS) or PBS alone. Animals were then remeasured with EIM at 4, 24, 48, or 72 hours and euthanized and quantitative assessment of muscle histology was performed. Parallel alterations in both 5 and 50 kHz EIM values were identified at 4 and 24 hours, including reductions in phase, reactance, and resistance. In PBS-treated animals these values normalized by 48 hours, whereas substantial reductions in phase and reactance in 5 kHz EIM values persisted at 48 and 72 hours (i.e., values of phase 72 hours post-injection were 6.51 ± 0.40 degrees for λ-carrageenan versus 8.44 ± 0.35 degrees for PBS p<0.001, n = 11 per group). The degree of basophilic area observed in muscle sections by histology correlated to the degree of phase change at these two time points (Rspearman = -0.51, p = 0.0029). Changes in low frequency EIM parameters are sensitive to the presence of inflammatory infiltrates, and have the potential of serving as a simple means of quantifying the presence and extent of muscle inflammation without the need for biopsy.
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Affiliation(s)
- Marie Mortreux
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Carson Semple
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Daniela Riveros
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Janice A. Nagy
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Seward B. Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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33
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Rutkove SB, Sanchez B. Electrical Impedance Methods in Neuromuscular Assessment: An Overview. Cold Spring Harb Perspect Med 2019; 9:cshperspect.a034405. [PMID: 30291145 DOI: 10.1101/cshperspect.a034405] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Electrical impedance methods have been used as evaluation tools in biological and medical science for well over 100 years. However, only recently have these techniques been applied specifically to the evaluation of conditions affecting nerve and muscle. This specific application, termed electrical impedance myography (EIM), is finding wide application as it can provide a quantitative index of muscle condition that can assist with diagnosis, track disease progression, and assess the beneficial impact of therapy. Using noninvasive surface methods, EIM has been studied in a number of conditions ranging from amyotrophic lateral sclerosis to muscular dystrophy to disuse atrophy. Data support that the technique is sensitive to disease status and can offer the possibility of performing clinical trials with fewer subjects than would otherwise be possible. Recent advances in the field include improved approaches for using EIM as a "virtual biopsy" and the development of combined needle impedance-electromyography technology.
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Affiliation(s)
- Seward B Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
| | - Benjamin Sanchez
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
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LoRusso S, Johnson NE, McDermott MP, Eichinger K, Butterfield RJ, Carraro E, Higgs K, Lewis L, Mul K, Sacconi S, Sansone VA, Shieh P, van Engelen B, Wagner K, Wang L, Statland JM, Tawil R. Clinical trial readiness to solve barriers to drug development in FSHD (ReSolve): protocol of a large, international, multi-center prospective study. BMC Neurol 2019; 19:224. [PMID: 31506080 PMCID: PMC6734593 DOI: 10.1186/s12883-019-1452-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 08/27/2019] [Indexed: 12/14/2022] Open
Abstract
Background Facioscapulohumeral muscular dystrophy (FSHD) is a dominantly-inherited progressive muscular dystrophy caused by de-repression of the DUX4 gene, which causes disease by a toxic-gain-of-function. As molecularly targeted drugs move from preclinical testing into human trials, it is essential that we validate clinical trial tools and methodology to facilitate the drug development process. Methods/design The primary goal of this study is to hasten drug development for FSHD by validating two novel clinical outcome assessments (COAs) and refining clinical trial strategies. We will perform an 18-month longitudinal study in 220 genetically confirmed and clinically affected participants using our FSHD Clinical Trial Research Network, comprised of 8 sites in the United States, and 3 collaborating sites in Europe. Visits occur at baseline and months 3, 12, and 18. At each visit we will collect: 1) a novel FSHD functional composite COA made up of 18 evaluator-administered motor tasks in the domains of shoulder/arm, hand, core/abdominal, leg, and balance function; and 2) electrical impedance myography as a novel muscle quality biomarker (US sites). Other COAs include 1) Domain 1 of the Motor Function Measure; 2) Reachable workspace; 3) orofacial strength using the Iowa Oral Performance Instrument; 4) lean muscle mass using dual-energy X-ray absorptiometry (DEXA); 5) strength as measured by quantitative myometry and manual muscle testing; and 6) the FSHD Health Index and other patient-reported outcomes. Plasma, DNA, RNA, and serum will be collected for future biomarker studies. We will use an industry standard multi-site training plan. We will evaluate the test-retest reliability, validity, and sensitivity to disease progression, and minimal clinically important changes of our new COAs. We will assess associations between demographic and genetic factors and the rate of disease progression to inform refinement of eligibility criteria for future clinical trials. Discussion To the best of our knowledge, this is the largest collaborative study of patients with FSHD performed in the US and Europe. The results of this study will enable more efficient clinical trial design. During the conduct of the study, relevant data will be made available for investigators or companies pursuing novel FSHD therapeutics. Trial registration clinicaltrials.gov NCT03458832; Date of registration: 1/11/2018 Electronic supplementary material The online version of this article (10.1186/s12883-019-1452-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Samantha LoRusso
- Department of Neurology, Ohio State University Wexner Medical Center, 395 W. 12th Ave., 7th Floor, Columbus, OH, 43210, USA
| | - Nicholas E Johnson
- Department of Neurology, Virginia Commonwealth University, 1101 East Marshall St, PO Box 980599, Richmond, VA, 23298, USA
| | - Michael P McDermott
- Department of Biostatistics and Computational Biology and Department of Neurology, University of Rochester Medical Center, 265 Crittenden Blvd., CU 420630, Rochester, NY, 14642, USA
| | - Katy Eichinger
- Department of Neurology, University of Rochester Medical Center, Box 673, 601 Elmwood Ave, Rochester, NY, 14642, USA
| | - Russell J Butterfield
- Department of Pediatrics and Neurology, University of Utah, Eccles Institute of Human Genetics, Room 2260A, 15 N 2030 E, Salt Lake City, UT, 84112, USA
| | - Elena Carraro
- The NEMO Clinical Center, Neurorehabilitation Unit, University of Milan, Piazza dell'Ospedale Maggiore, 3, Milan, 20162, Italy
| | - Kiley Higgs
- Department of Neurology, University of Kansas Medical Center, 3901 Rainbow Blvd, MS 2012, Kansas City, KS, 66160, USA
| | - Leann Lewis
- Department of Neurology, University of Rochester Medical Center, Box 673, 601 Elmwood Ave, Rochester, NY, 14642, USA
| | - Karlien Mul
- Department of Neurology, Radboud University Medical Center, Reinier Postlaan 4 (935), 6525, GC, Nijmegen, The Netherlands
| | - Sabrina Sacconi
- Université Côte d'Azur, Peripheral Nervous System, Centre Hospitalier Universitaire de Nice, Muscle & ALS Department, Pasteur 2 Hospital, 30 Voie Romaine, 06001, Nice Cedex 1, France
| | - Valeria A Sansone
- The NEMO Clinical Center, Neurorehabilitation Unit, University of Milan, Piazza dell'Ospedale Maggiore, 3, Milan, 20162, Italy
| | - Perry Shieh
- Department of Neurology, University of California, Los Angeles, 300 Medical Plaza, Suite B-200, Los Angeles, CA, 90095, USA
| | - Baziel van Engelen
- Department of Neurology, Radboud University Medical Center, Reinier Postlaan 4 (935), 6525, GC, Nijmegen, The Netherlands
| | - Kathryn Wagner
- Center for Genetic Muscle Disorders, Kennedy Krieger Institute, 707 N. Broadway, Baltimore, MD, USA
| | - Leo Wang
- Department of Neurology, University of Washington, 1959 NE Pacific St, Seattle, WA, 98195, USA
| | - Jeffrey M Statland
- Department of Neurology, University of Kansas Medical Center, 3901 Rainbow Blvd, MS 2012, Kansas City, KS, 66160, USA.
| | - Rabi Tawil
- Department of Neurology, University of Rochester Medical Center, Box 673, 601 Elmwood Ave, Rochester, NY, 14642, USA
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Stålberg E, van Dijk H, Falck B, Kimura J, Neuwirth C, Pitt M, Podnar S, Rubin DI, Rutkove S, Sanders DB, Sonoo M, Tankisi H, Zwarts M. Standards for quantification of EMG and neurography. Clin Neurophysiol 2019; 130:1688-1729. [DOI: 10.1016/j.clinph.2019.05.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 05/07/2019] [Accepted: 05/09/2019] [Indexed: 12/11/2022]
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Abstract
Advances in high-resolution ultrasound have provided clinicians with unique opportunities to study diseases of the peripheral nervous system. Ultrasound complements the clinical and electrophysiology exam by showing the degree of abnormalities in myopathies, as well as spontaneous muscle activities in motor neuron diseases and other disorders. In experienced hands, ultrasound is more sensitive than MRI in detecting peripheral nerve pathologies. It can also guide needle placement for electromyography exam, therapeutic injections, and muscle biopsy. Ultrasound enhances the ability to detect carpal tunnel syndrome and other focal nerve entrapment, as well as pathological nerve enlargements in genetic and acquired neuropathies. Furthermore, ultrasound can potentially be used as a biomarker for muscular dystrophy and spinal muscular atrophy. The combination of electromyography and ultrasound can increase the diagnostic certainty of amyotrophic lateral sclerosis, aid in the localization of brachial plexus or peripheral nerve trauma and allow for surveillance of nerve tumor progression in neurofibromatosis. Potential limitations of ultrasound include an inability to image deeper structures, with lower sensitivities in detecting neuromuscular diseases in young children and those with mitochondrial myopathies, due to subtle changes or early phase of the disease. As well, its utility in detecting critical illness neuromyopathy remains unclear. This review will focus on the clinical applications of neuromuscular ultrasound. The diagnostic values of ultrasound for screening of myopathies, neuropathies, and motor neuron diseases will be presented.
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Permittivity of ex vivo healthy and diseased murine skeletal muscle from 10 kHz to 1 MHz. Sci Data 2019; 6:37. [PMID: 31000708 PMCID: PMC6472406 DOI: 10.1038/s41597-019-0045-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 03/15/2019] [Indexed: 12/31/2022] Open
Abstract
A better understanding of the permittivity property of skeletal muscle is essential for the development of new diagnostic tools and approaches for neuromuscular evaluation. However, there remain important knowledge gaps in our understanding of this property in healthy and diseased skeletal muscle, which hinder its translation into clinical application. Here, we report the permittivity of gastrocnemius muscle in healthy wild type mice and murine models of spinal muscular atrophy, muscular dystrophy, diabetes, amyotrophic lateral sclerosis and in a model of myofiber hypertrophy. Data were measured ex vivo from 10 kHz to 1 MHz using the four-electrode impedance technique. Additional quantitative histology information were obtained. Ultimately, the normative data reported will offer the scientific community the opportunity to develop more accurate models for the validation and prediction of experimental observations in both pre-clinical and clinical neuromuscular disease research. Design Type(s) | physiological data analysis objective • strain comparison design • ex vivo design | Measurement Type(s) | permittivity property | Technology Type(s) | impedance analyzer | Factor Type(s) | temporal_instant • frequency • Mouse Model • experimental condition | Sample Characteristic(s) | Mus musculus • skeletal muscle tissue |
Machine-accessible metadata file describing the reported data (ISA-Tab format)
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Roy B, Darras BT, Zaidman CM, Wu JS, Kapur K, Rutkove SB. Exploring the relationship between electrical impedance myography and quantitative ultrasound parameters in Duchenne muscular dystrophy. Clin Neurophysiol 2019; 130:515-520. [PMID: 30772764 DOI: 10.1016/j.clinph.2019.01.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 12/10/2018] [Accepted: 01/13/2019] [Indexed: 12/14/2022]
Abstract
OBJECTIVES Quantitative ultrasound (QUS), including grayscale level analysis (GLA) and quantitative backscatter analysis (QBA), and electrical impedance myography (EIM) have been proposed as biomarkers in Duchenne muscular dystrophy (DMD). However, the relationship between these methods has not been assessed. METHODS QUS values (including GLA and QBA) and several EIM measures were recorded from six muscles in 36 DMD and 29 healthy boys between ages 5 and 13 years at baseline, 6-months, and 12-months. RESULTS In the DMD boys, a moderate correlation was noted between QUS and EIM parameters, with the strongest correlations being identified for averaged muscle values. Of the individual muscles, biceps brachii and deltoid showed the strongest correlations. For example, in biceps, the QBA/EIM correlation coefficient (Spearman rho) was ≥0.70 (p < 0.01). Importantly, changes in QUS values over 12 months also correlated moderately with changes in EIM parameters and EIM/QBA rho values mostly varied between -0.53 and -0.70 (p ≤ 0.02). No significant correlations were identified in the healthy boys. CONCLUSIONS A moderate correlation of QUS with EIM in DMD boys suggests that the two technologies provide related data but are sensitive to different pathological features of muscle. SIGNIFICANCE The use of both technologies jointly in assessing DMD progression and response to therapy should be considered.
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Affiliation(s)
- Bhaskar Roy
- Beth Israel Deaconess Medical Center, Boston, MA, USA
| | | | | | - Jim S Wu
- Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Kush Kapur
- Boston Children's Hospital, Boston, MA, USA
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Wang Y, Freedman L, Buck M, Bohorquez J, Rutkove SB, Keel J. Electrical Impedance Myography for Assessing Paraspinal Muscles of Patients with Low Back Pain. JOURNAL OF ELECTRICAL BIOIMPEDANCE 2019; 10:103-109. [PMID: 33584890 PMCID: PMC7851978 DOI: 10.2478/joeb-2019-0015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Indexed: 06/12/2023]
Abstract
The objective of this study was to determine the potential value of electrical impedance myography (EIM) for assessing lumbosacral paraspinal muscle (LPM) condition in lower back pain (LBP) patients. Standard methods for assessing the condition of LPMs, such as magnetic resonance imaging, are inconvenient and expensive. One tool that could be useful for this purpose is electrical impedance myography (EIM) a technique that can be performed rapidly at the bedside. After undergoing a screening history and examination, subjects were studied with the mView EIM device (Myolex, Inc, Boston). Bilateral LPMs were measured three times each and the two closest sets of measurements averaged on each side. Data analysis included non-parametric two-group comparisons between healthy subjects and back pain patients, receiver-operating curve analyses, and correlation analyses to age and body mass index. A total of 86 healthy individuals (median age (interquartile range) (IQR), 45.5 years (30.3-56.0 years), 42 men, 44 women) and 47 LBP (median age 51.0 year (39.5-57.5) years, 21 men, 26 women) were enrolled. Median EIM 100kHz phase was lower in the LBP patients (9.3°(IQR 8.4°-10.6°) versus 11.4°(IQR 9.4°-13.0°), p = 0.0007). Significantly increased normalized side-to-side differences were present for all three EIM variables (e.g., median 100 kHz phase 0.15 (IQR 0.07-0.31 in LBP patients versus 0.09 (IQR 0.04-0.17) in healthy individuals). A significant correlation between 100 kHz EIM phase and reactance was found with age (Rspearman=-0.46, P=0.0002 and Rspearman=-0.440, P=0.0003) but not for resistance. This study provides early evidence supporting that EIM has the potential to serve as a useful tool for evaluating the condition of LPMs.
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Affiliation(s)
- Yun Wang
- Department of Neurology, Beijing Chaoyang Hospital, Capital Medical University Beijing, China
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA
| | | | | | | | - Seward B. Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA
| | - John Keel
- Emory Orthopaedics/Spine Center, Emory University, Atlanta, USA
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Hobson-Webb LD, Zwelling PJ, Pifer AN, Killelea CM, Faherty MS, Sell TC, Pastva AM. Point of Care Quantitative Assessment of Muscle Health in Older Individuals: An Investigation of Quantitative Muscle Ultrasound and Electrical Impedance Myography Techniques. Geriatrics (Basel) 2018; 3:geriatrics3040092. [PMID: 31011127 PMCID: PMC6371147 DOI: 10.3390/geriatrics3040092] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 12/08/2018] [Accepted: 12/13/2018] [Indexed: 12/13/2022] Open
Abstract
Background: Muscle health is recognized for its critical role in the functionality and well-being of older adults. Readily accessible, reliable, and inexpensive methods of measuring muscle health are needed to advance research and clinical care. Methods: In this prospective, blinded study, 27 patients underwent quantitative muscle ultrasound (QMUS), standard electrical impedance myography (sEIM), and handheld electrical impedance myography (hEIM) of the anterior thigh musculature by two independent examiners. Subjects also had dual-energy X-ray absorptiometry (DEXA) scans and standardized tests of physical function and strength. Data were analyzed for intra- and inter-rater reliability, along with correlations with DEXA and physical measures. Results: Measures of intra- and inter-rater reliability were excellent (>0.90) for all QMUS, sEIM, and hEIM parameters except intra-rater reliability of rectus femoris echointensity (0.87–0.89). There were moderate, inverse correlations between QMUS, sEIM, and hEIM parameters and measures of knee extensor strength. Moderate to strong correlations (0.57–0.81) were noted between investigational measures and DEXA-measured fat mass. Conclusions: QMUS, sEIM and hEIM were highly reliable in a controlled, same-day testing protocol. Multiple correlations with measures of strength and body composition were noted for each method. Point-of-care technologies may provide an alternative means of measuring health.
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Affiliation(s)
- Lisa D Hobson-Webb
- Duke University Department of Neurology/Neuromuscular Division, Durham, NC 27710, USA.
| | - Paul J Zwelling
- Duke University Department of Neurology/Neuromuscular Division, Durham, NC 27710, USA.
| | - Ashley N Pifer
- Duke University Department of Neurology/Neuromuscular Division, Durham, NC 27710, USA.
| | - Carrie M Killelea
- Duke University Department of Orthopaedic Surgery, Durham, NC 27710, USA.
- Michael W. Krzyzewski Human Performance Laboratory, Durham, NC 27710, USA.
| | - Mallory S Faherty
- Duke University Department of Orthopaedic Surgery, Durham, NC 27710, USA.
- Michael W. Krzyzewski Human Performance Laboratory, Durham, NC 27710, USA.
| | - Timothy C Sell
- Duke University Department of Orthopaedic Surgery, Durham, NC 27710, USA.
- Michael W. Krzyzewski Human Performance Laboratory, Durham, NC 27710, USA.
| | - Amy M Pastva
- Duke University Department of Orthopaedic Surgery, Durham, NC 27710, USA.
- Duke University Claude D. Pepper Older American Independence Center Durham, NC 27710, USA.
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Fu B, Freeborn TJ. Estimating Localized Bio-impedance with Measures from Multiple Redundant Electrode Configurations. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2018; 2018:4351-4354. [PMID: 30441317 DOI: 10.1109/embc.2018.8513382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In most bio-impedance applications, measurements are collected from a single electrode configuration though multi-electrode systems could monitor different tissue sites or serve as a source of redundancy in case of electrode malfunction. However, comparison of impedance data collected from different electrode configurations is difficult. This article proposes an approach to estimate the current tissue impedance collected from a fixed electrode configuration using measurements from different sites of the same localized tissue. Estimated impedance is calculated using the ratio between impedance values from different electrode configurations collected prior to the electrode malfunction event. This approach is validated using measurements of a human forearm collected from 3 kHz to 1 MHz collected with 4 electrode configurations over 3 days. The estimation results using this approach show maximum estimation errors of 2.3% and 16.9% for the resistance and reactance, respectively, compared to the measured impedance.
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Kwon H, Malik WQ, Rutkove SB, Sanchez B. Separation of Subcutaneous Fat From Muscle in Surface Electrical Impedance Myography Measurements Using Model Component Analysis. IEEE Trans Biomed Eng 2018; 66:354-364. [PMID: 29993468 DOI: 10.1109/tbme.2018.2839977] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Electrical impedance myography (EIM) is a relatively new technique to assess neuromuscular disorders (NMD). Although the application of EIM using surface electrodes (sEIM) has been adopted by the neurology community in recent years to evaluate NMD status, sEIM's sensitivity as a biomarker of skeletal muscle condition is impacted by subcutaneous fat (SF) tissue. Here, we develop a method that is able to remove the contribution of SF from sEIM data. METHODS We evaluate independent component analysis (ICA) and principal component analysis (PCA) for this purpose. Then, we introduce the so-called model component analysis (MCA). All methods are validated with numerical simulations using impedivity data from SF and muscle tissues. The methods are then tested with measurements performed in diseased individuals ( n=3). RESULTS Simulations demonstrate that MCA is the most accurate method at separating the impedivity of SF and muscle tissues with the accuracy being 99.2%, followed by ICA with 51.4%, and finally PCA with 38.5%. Experimental results from sEIM data measured on the triceps brachii of patients are consistent with muscle grayscale level values obtained using ultrasound imaging. CONCLUSION MCA can be used to separate the impedivity of SF and muscle tissues from sEIM data, thus increasing the sensitivity to detect changes in the muscle. SIGNIFICANCE MCA can make the sEIM technique a better diagnostic tool and biomarker of disease progression and response to therapy by removing the confounding effect of SF tissue in NMD patients with excess subcutaneous fat tissue for any reason.
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Mul K, Heatwole C, Eichinger K, Dilek N, Martens WB, Van Engelen BGM, Tawil R, Statland JM. Electrical impedance myography in facioscapulohumeral muscular dystrophy: A 1-year follow-up study. Muscle Nerve 2018; 58:213-218. [PMID: 29543984 DOI: 10.1002/mus.26127] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2018] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Electrical impedance myography (EIM) is a noninvasive technique for measuring muscle composition and a potential physiological biomarker for facioscapulohumeral muscular dystrophy (FSHD). METHODS Thirty-two participants with genetically confirmed and clinically affected FSHD underwent EIM in 7 muscles bilaterally. Correlations between EIM and baseline clinical measures were used to select EIM variables of interest in FSHD, and EIM and clinical measures were followed for 1 year. RESULTS There were no significant changes in the EIM variables. Although 50-kHZ reactance correlated the strongest with clinical measures at baseline, the 50-211-kHZ phase ratio demonstrated lower within-subject 12-month variability, potentially offering sample size savings for FSHD clinical trial planning. DISCUSSION EIM did not identify significant disease progression over 12 months. It is currently unclear whether this is because of limitations of the technology or the slow rate of disease progression in this cohort of FSHD patients over this period of time. Muscle Nerve 58: 213-218, 2018.
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Affiliation(s)
- Karlien Mul
- Department of Neurology, University of Kansas Medical Center, 4330 Shawnee Mission Parkway, Suite 323 Fairway, Kansas, 66205, USA.,Department of Neurology, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Chad Heatwole
- Department of Neurology, University of Rochester Medical Center, Rochester, New York, USA
| | - Katy Eichinger
- Department of Neurology, University of Rochester Medical Center, Rochester, New York, USA
| | - Nuran Dilek
- Department of Neurology, University of Rochester Medical Center, Rochester, New York, USA
| | - William B Martens
- Department of Neurology, University of Rochester Medical Center, Rochester, New York, USA
| | - Baziel G M Van Engelen
- Department of Neurology, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Rabi Tawil
- Department of Neurology, University of Rochester Medical Center, Rochester, New York, USA
| | - Jeffrey M Statland
- Department of Neurology, University of Kansas Medical Center, 4330 Shawnee Mission Parkway, Suite 323 Fairway, Kansas, 66205, USA.,Department of Neurology, University of Rochester Medical Center, Rochester, New York, USA
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Electrical impedance myography as a biomarker of myostatin inhibition with ActRIIB-mFc: a study in wild-type mice. Future Sci OA 2018; 4:FSO308. [PMID: 30057785 PMCID: PMC6060391 DOI: 10.4155/fsoa-2018-0002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 03/15/2018] [Indexed: 12/14/2022] Open
Abstract
Aim: We sought to determine the sensitivity of electrical impedance myography (EIM) to myofiber hypertrophy induced by treatment with various doses of ActRIIB-mFc, an inhibitor of myostatin signaling. Methods: Wild-type C57BL/6 J mice (n = 40, male) were treated with three different doses of ActRIIB-mFc (i.e., RAP-031) or vehicle twice weekly for 5 weeks. End point assessments included gastrocnemius EIM, force measurements, muscle mass and myofiber size quantification. Results: ActRIIB-mFc increased body mass, muscle mass and myofiber size across all doses. Alterations in EIM 50 kHz phase and center frequency (fc) were also present, with trends in a dose-dependent fashion. Significant correlations between EIM parameters and myofiber/functional data were identified. Conclusion: EIM outcomes can serve as effective biomarkers of myostatin signaling inhibition, demonstrating a dose sensitivity and correlation to standard assessments. We were interested in studying the sensitivity of a technique, called electrical impedance myography (EIM), to noninvasively assess the size of muscle fibers. In this technique a minute electrical current is used to probe the tissue. To do so, we gave a drug (ActRIIB-mFc) to mice that enlarges muscle fibers at three different doses. We were able to show that the EIM technique was able to detect this differential effect and functional changes induced by the drug correlated to the EIM data. This work suggests that EIM will be useful as a noninvasive marker muscle health.
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Kapur K, Taylor RS, Qi K, Nagy JA, Li J, Sanchez B, Rutkove SB. Predicting myofiber size with electrical impedance myography: A study in immature mice. Muscle Nerve 2018; 58:10.1002/mus.26111. [PMID: 29476692 PMCID: PMC6108958 DOI: 10.1002/mus.26111] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/20/2018] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Electrical impedance can be used to estimate cellular characteristics. We sought to determine whether it could be used to approximate myofiber size using standard prediction modeling approaches. METHODS Forty-four C57BL/6J wild-type immature mice of varying ages underwent electrical impedance myography (EIM) with a needle electrode array placed in the gastrocnemius. Animals were then humanely killed and muscle fixed, stained, and myofiber size quantified. Two different statistical prediction models were then applied. RESULTS Impedance parameters showed major variation with increasing myofiber size. The prediction models based on EIM data alone were able to predict fiber size, with errors in the range of ±69.05-78.44 µm2 (16.19%-18.40% with respect to the average myofiber size). DISCUSSION By using well-established statistical models, EIM data alone can provide a satisfactory estimate of myofiber size. Additional study of this approach for approximating myofiber size without the requirement of removing tissue for histological analysis is warranted. Muscle Nerve, 2018.
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Affiliation(s)
- Kush Kapur
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, 02115, USA
| | - Rebecca S Taylor
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, TCC-810 Boston, Massachusetts, 02215, USA
| | - Kristin Qi
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, TCC-810 Boston, Massachusetts, 02215, USA
| | - Janice A Nagy
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, TCC-810 Boston, Massachusetts, 02215, USA
| | - Jia Li
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, TCC-810 Boston, Massachusetts, 02215, USA
| | - Benjamin Sanchez
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, TCC-810 Boston, Massachusetts, 02215, USA
| | - Seward B Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, TCC-810 Boston, Massachusetts, 02215, USA
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Present Uses, Future Applications, and Technical Underpinnings of Electrical Impedance Myography. Curr Neurol Neurosci Rep 2017; 17:86. [DOI: 10.1007/s11910-017-0793-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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