Muscle Elasticity Assessment of Postherpetic Neuralgia Using Elasticity Ultrasound

Study Overview
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Brief Summary
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Herpes zoster (HZ), also known as shingles, is caused by the varicella-zoster virus (VZV). Approximately 1/4 of the global population is affected by HZ, with statistics showing that about 90% of shingles patients experience acute neuralgia, and about 1/3 develop postherpetic neuralgia (PHN) after shingles. In PHN patients, about 30%-50% of the pain can persist for more than one year, and some cases can last for more than 10 years. PHN is a common complication of HZ characterized by intense pain in the area where the rash has healed, often described as burning, electric shock-like, or stabbing pain, severely affecting patients' sleep, emotions, work, and daily life. Additionally, approximately 43% of PHN patients exhibit symptoms of toxic anxiety or depression, significantly impacting their quality of life and increasing the societal burden. Due to the global aging population, the incidence of HZ and PHN is expected to significantly increase in the next 10 years, making effective prevention and treatment of PHN an urgent health issue. Although various treatments are available for PHN, a small number of patients remain unresponsive to multiple therapies, resulting in treatment-resistant chronic pain. The lack of a clear understanding of the underlying mechanisms contributes to the suboptimal treatment outcomes for PHN. Elastography, a technique that quantifies the mechanical properties of tissues by measuring their natural elasticity, trauma, degeneration, and healing processes, has shown promise as an innovative approach. Shear wave elastography (SWE) has been used to study the biomechanical characteristics of skeletal muscles by measuring the propagation speed of shear waves induced by ultrasound to quantify the shear elastic modulus, which characterizes the stiffness of soft tissues. In this study, the investigators intend to use elastography to observe the elasticity of muscle tissue in the lesions of PHN patients, with the unaffected side serving as a control. Elastography offers non-invasive, convenient, and straightforward advantages, further contributing to providing new directions for treatment and revealing the role of muscle tissue in PHN by offering new evidence. It also offers new treatment options and targets for PHN patients.

Official Title
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Preliminary Cohort Study on Muscle Elasticity Ultrasound Evaluation and Pathophysiological Changes in Postherpetic Neuralgia

Conditions
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Shear Wave Elastography

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged 18 and above. Patients who were diagnosed with postherpetic neuralgia (PHN). Exclusion Criteria: Patients who had any neuromuscular disorders, or malignancy. Patients were pregnant, had reported a history of neuromuscular disorders, or were on muscle relaxants and/or other drugs aﬀecting the muscles. Patients with active or passive central and peripheral nervous system diseases, mental disorders, and a body mass index (BMI) greater than 30 kg/m2. Patients who had previous surgery in the area of PHN lesions or coexisting muscle-altering conditions. Patients who were allergic to local anesthetics. Patients or family members unable to comprehend the conditions and objectives of this study.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Postherpetic neuralgia patient NO1<br>Postherpetic neuralgia patients often experience unilateral symptoms, with lesions predominantly occurring on one side of the chest wall. Therefore, the investigators can perform muscle elastography using ultrasound on both the unaffected side and the affected side of the patient to study the changes in muscle elasticity on the affected side. | |
| Postherpetic neuralgia patient NO2<br>Postherpetic neuralgia patients often experience unilateral symptoms, with lesions predominantly occurring on one side of the chest wall. Therefore, the investigators can perform muscle elastography using ultrasound on both the unaffected side and the affected side of the patient to study the changes in muscle elasticity on the affected side. | |
| Postherpetic neuralgia patient NO3<br>Postherpetic neuralgia patients often experience unilateral symptoms, with lesions predominantly occurring on one side of the chest wall. Therefore, the investigators can perform muscle elastography using ultrasound on both the unaffected side and the affected side of the patient to study the changes in muscle elasticity on the affected side. | |
| Postherpetic neuralgia patient NO4<br>Postherpetic neuralgia patients often experience unilateral symptoms, with lesions predominantly occurring on one side of the chest wall. Therefore, the investigators can perform muscle elastography using ultrasound on both the unaffected side and the affected side of the patient to study the changes in muscle elasticity on the affected side. | |
| Postherpetic neuralgia patient NO5<br>Postherpetic neuralgia patients often experience unilateral symptoms, with lesions predominantly occurring on one side of the chest wall. Therefore, the investigators can perform muscle elastography using ultrasound on both the unaffected side and the affected side of the patient to study the changes in muscle elasticity on the affected side. | |
| Postherpetic neuralgia patient NO6<br>Postherpetic neuralgia patients often experience unilateral symptoms, with lesions predominantly occurring on one side of the chest wall. Therefore, the investigators can perform muscle elastography using ultrasound on both the unaffected side and the affected side of the patient to study the changes in muscle elasticity on the affected side. | |
| Postherpetic neuralgia patient NO7<br>Postherpetic neuralgia patients often experience unilateral symptoms, with lesions predominantly occurring on one side of the chest wall. Therefore, the investigators can perform muscle elastography using ultrasound on both the unaffected side and the affected side of the patient to study the changes in muscle elasticity on the affected side. | |
| Postherpetic neuralgia patient NO8<br>Postherpetic neuralgia patients often experience unilateral symptoms, with lesions predominantly occurring on one side of the chest wall. Therefore, the investigators can perform muscle elastography using ultrasound on both the unaffected side and the affected side of the patient to study the changes in muscle elasticity on the affected side. | |
| Postherpetic neuralgia patient NO9<br>Postherpetic neuralgia patients often experience unilateral symptoms, with lesions predominantly occurring on one side of the chest wall. Therefore, the investigators can perform muscle elastography using ultrasound on both the unaffected side and the affected side of the patient to study the changes in muscle elasticity on the affected side. | |
| Postherpetic neuralgia patient NO10<br>Postherpetic neuralgia patients often experience unilateral symptoms, with lesions predominantly occurring on one side of the chest wall. Therefore, the investigators can perform muscle elastography using ultrasound on both the unaffected side and the affected side of the patient to study the changes in muscle elasticity on the affected side. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Shear Wave Elastography | Shear-wave elastography has recently emerged as a promising assessment tool with the potential for diagnosing and monitoring muscle changes and as a noninvasive method to estimate muscle. | up to 1 months |