An observational study in Lower Extremity Varicose Veins, Radiofrequency Ablation and Microwave Ablation, sponsored by Chunshui He. Active, not recruiting at 1 site in China. Open to participants aged 18 Years to 75 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-30.
Sponsored by Chunshui He · Observational
Among 244 studies in Pain with a site in China — 64 open to participants now, 70 under way, 2 of them phase 3. Pain · China.
Among the 244 studies in Pain with a site in China, this one is the 23rd largest by planned enrollment of the 34 observational ones, is one of 23 that started in 2026, is one of 35 observational ones, reaches primary completion later than 37 of the 69 other live ones, and was the 242nd registered.
10,054 studies on the registry are indexed under Pain; 1,649 are open to participants now.
This study's planned enrollment of 130 is above the median of 100 across 1,252 observational studies indexed under Pain.
Browse Pain studies →64 of the 244 studies in Pain with a site in China are open now, in 1 country. Each count lists the studies.
Of the 929 Pain studies recruiting now, 384 (41%) set no upper age limit and 434 (47%) stop at 75 or younger; 146 take children under 18; 222 take healthy volunteers.
This study: 18 Years to 75 Years · all sexes · healthy volunteers too.
The full table on the hub →244 studies; the count open now beside each. This study's row is marked.
First in 1992; this study’s year is marked. 23 started in 2026.
Median enrollment 120 across the 209 interventional studies, 169 across the 34 observational. Of the 121 that completed or were terminated, 17 (14%) have results posted.
50 of 244 have an industry lead sponsor. The 10 most frequent:
Chunshui He is the lead sponsor of 2 studies on the registry; 1 is open to participants now.
Chunshui He has 1 study filed under Pain — fewer than ten, so there is no comparison to draw.
30 of the studies in Pain with a site in China that are under way reach primary completion within a year, 1 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT07872826Phase 3The Third Xiangya Hospital of Central South UniversityA Clinical Trial Evaluating the Efficacy and Safety of Local Infiltration of RF16001 for Injection for Analgesia After Total Hip Arthroplasty in China | 2027-06-30 |
| NCT07212127First Affiliated Hospital of the Chinese People's Liberation Army Naval Medical UniversityAnalgesic Effect of TENS-WAA Combined With Tramadol Hydrochloride During Oocyte Retrieval Surgery | 2026-11-08 |
| NCT07533786Haisco Pharmaceutical Group Co., Ltd.A Clinical Trial Evaluating the Efficacy and Safety of HSK55718 in Patients for Postoperative Pain Treatment in Abdominal Surgery | 2026-11-22 |
| NCT06553495Jie ChenA Comparative Analysis of Intertransverse Nerve Block and Paravertebral Nerve Block in Endoscopic Hepatectomy | 2026-11-30 |
| NCT07557823Second Affiliated Hospital, School of Medicine, Zhejiang UniversityTranscutaneous Auricular Vagus Nerve Stimulation Combined With Cervical Epidural Injection for Cervical Radiculopathy | 2026-12-30 |
Among the 244 studies in Pain with a site in China, from their registry updates:
This study compares two common heat-based procedures for treating varicose veins in the legs: radiofrequency ablation (RFA) and microwave ablation (MWA). Both treatments use heat to close off diseased veins, but they work differently-RFA heats through direct contact, while MWA uses microwave energy that spreads heat more widely.
The main question is: Which procedure causes less pain during the surgery?
Participants will be randomly assigned to receive either RFA or MWA. Since the surgery is done under local anesthesia (not general anesthesia), patients remain awake throughout. We will measure their pain at four key moments:
When the needle is first inserted
Right after injecting the numbing fluid (tumescent anesthesia)
During the heat treatment itself
At the end of the entire procedure
We will also track how much numbing fluid is used, how long the procedure takes, and any side effects. Patients will be followed for 30 days after surgery to monitor recovery and satisfaction.
The goal is to find out whether one method is more comfortable for patients, and to identify which factors (such as age, vein size, or anxiety level) affect pain during each procedure. This will help doctors choose the best approach for each patient and improve the overall treatment experience.
The study population will be selected from adult patients presenting to the Department of Vascular Surgery at the Hospital of Chengdu University of Traditional Chinese Medicine with symptomatic lower extremity varicose veins. The study population will be recruited from adult patients presenting to the Department of Vascular Surgery at the Hospital of Chengdu University of Traditional Chinese Medicine with symptomatic lower extremity varicose veins. Eligible participants are individuals aged 18 to 75 years with ultrasound-confirmed great saphenous vein incompetence (reflux time >0.5 seconds), vein diameter of 4-12 mm, and CEAP clinical class C2 to C6. Exclusion criteria include prior ipsilateral venous interventions, deep vein thrombosis, arterial disease (ABI \<0.7), severe organ dysfunction, pregnancy, chronic pain, or local anesthetic allergy. Consecutive eligible patients will be invited to participate until the target of 130 patients (65 per group) is reached.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
INR, PT and aPTT (clotting tests)
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Procedure: Radiofrequency ablation
Procedure: Microwave Ablation
Endovenous thermal ablation of the incompetent great saphenous vein (GSV) using radiofrequency energy. The procedure is performed under tumescent local anesthesia (TLA). The device delivers segmental radiofrequency energy (460 kHz) through a catheter placed within the GSV, heating the vein wall to approximately 120°C, causing collagen contraction and vein occlusion.
Endovenous thermal ablation of the incompetent great saphenous vein (GSV) using microwave energy. The procedure is performed under tumescent local anesthesia (TLA). The device delivers microwave energy (2450 MHz) through an antenna placed within the GSV, generating dielectric heating that causes thermal coagulation and vein closure.
Pain Score at Tumescent Anesthesia Injection Completion (VAS-T2)
Pain intensity immediately after completion of tumescent local anesthesia (TLA) injection, assessed using the Visual Analog Scale (VAS). VAS is a clinical assessment tool that quantifies pain intensity using a linear scale approximately 10 centimeters long. The two ends of the scale are marked as "0" (no pain) and "10" (worst imaginable pain).The patient reports the most significant pain experienced during the entire TLA injection phase (from the first puncture to completion of injection).
Time frame: Measured immediately after TLA injection is completed and ultrasound confirms satisfactory perivenous fluid infiltration (before ablation begins) - Intraoperative (Day 0)
Pain Score During Catheter Ablation (VAS-T3)
Pain intensity during the endovenous ablation phase, assessed using the Visual Analog Scale (VAS). The patient reports the most significant pain experienced during the entire ablation phase (from activation of the ablation device to completion of great saphenous vein trunk ablation).Visual Analog Scale (VAS): Minimum = 0, Maximum = 10. Higher scores indicate worse outcome (greater pain intensity). A score of 0 represents "no pain" and a score of 10 represents "worst imaginable pain."
Time frame: Measured immediately after completion of GSV trunk ablation and withdrawal of the ablation catheter
Intraoperative Pain Trajectory (Group × Time Interaction)
Overall pattern of intraoperative pain across the four procedural time points, assessed to determine whether the pain trajectory differs between RFA and MWA groups. This is a composite measure derived by aggregating VAS scores from all four time points into a single repeated-measures model.VAS score (0-10 cm) analyzed as a repeated measure; reported as the group × time interaction effect (F-statistic and p-value) from a linear mixed effects model. VAS scores from T1, T2, T3, and T4 will be combined using a linear mixed effects model (LMM) with fixed effects for group, time, and group × time interaction, and random effects for individual patients. The reported value is the group × time interaction effect, which indicates whether the pain trajectory differs between groups.
Time frame: Assessed at four time points: T1 (immediately after sheath placement), T2 (immediately after TLA injection), T3 (immediately after ablation completion), and T4 (immediately after procedure completion)
TLA Total Injection Volume
Total volume of tumescent local anesthesia (TLA) solution injected during the procedure.Milliliters (mL)
Time frame: Recorded during the TLA injection phase
RFA Ablation Energy Parameters
Device-specific energy parameters for the RFA group, including temperature achieved.Temperature (°C)
Time frame: Intraoperative (Day 0); recorded during the ablation phase
MWA Ablation Energy Parameters
Device-specific energy parameters for the MWA group, including power output .Power (Watts)
Time frame: Recorded during the ablation phase
Postoperative Pain at 2 Hours
Pain intensity at rest in the treated leg at 2 hours after procedure completion.VAS score (0-10 cm)
Time frame: Postoperative 2 hours
Postoperative Pain at 24 Hours
Pain intensity at rest in the treated leg at 24 hours after procedure completion.VAS score (0-10 cm),Visual Analog Scale (VAS): Minimum = 0, Maximum = 10. Higher scores indicate worse outcome (greater pain intensity)
Time frame: Postoperative 24 hours (Day 1)
Postoperative Pain at 7 Days
Pain intensity at rest in the treated leg at 7 days after procedure completion.VAS score (0-10 cm)
Time frame: Postoperative 7 days (Day 7)
Postoperative Pain at 30 Days
Pain intensity at rest in the treated leg at 30 days after procedure completion.VAS score (0-10 cm),VAS: Minimum = 0, Maximum = 10. Higher scores indicate worse outcome (greater pain intensity)
Time frame: Postoperative 30 days (Day 30)
Venous Clinical Severity Score (VCSS) at Baseline
Disease-specific clinical severity assessed using the Venous Clinical Severity Score (VCSS) before treatment.VCSS score (0-30)
Time frame: Baseline (preoperative, within 7 days before surgery)
Venous Clinical Severity Score (VCSS) at 30 Days
Disease-specific clinical severity assessed using the Venous Clinical Severity Score (VCSS) at 30 days after treatment.VCSS is a standardized tool for assessing the severity of lower extremity venous disease. It consists of 10 items (pain, varicose veins, edema, pigmentation, inflammation, induration, ulcer number/size/duration, and compression therapy). Each item is scored from 0 to 3, with a total score ranging from 0 to 30. Higher scores indicate more severe clinical symptoms.
Time frame: Postoperative 30 days (Day 30)
Change in Venous Clinical Severity Score (ΔVCSS)
Change in disease-specific clinical severity from baseline to 30 days after treatment. This is a derived composite measure calculated by subtracting the 30-day VCSS from the baseline VCSS.VCSS score change (baseline VCSS minus 30-day VCSS)
Time frame: Baseline to postoperative 30 days
Incidence of Adverse Events
Incidence and severity of all procedure-related adverse events from intraoperative period through 30 days post-procedure.Count and percentage of patients with ≥1 adverse event
Time frame: Intraoperative through postoperative 30 days
Factors Influencing Intraoperative Pain - Univariable Analysis
Exploratory analysis to identify patient, anatomical, and procedural factors associated with pain at each intraoperative time point.Correlation coefficient (r or ρ) or regression coefficient (β) with 95% CI.Each candidate factor is tested individually against each VAS outcome (T1-T4). Results are reported as point estimates with 95% confidence intervals.
Time frame: Intraoperative (Day 0); using data from all four time points (T1, T2, T3, T4)
Factors Influencing Intraoperative Pain - Multivariable Analysis
Exploratory multivariable analysis to identify independent factors influencing pain at the two core time points (VAS-T2 and VAS-T3).Regression coefficient (β) with 95% CI.Separate multivariable linear regression models for VAS-T2 and VAS-T3. Each model includes group assignment, prespecified core variables, and univariable significant factors.
Time frame: Intraoperative (Day 0); using data from T2 (TLA injection) and T3 (ablation)
Effect Modification by Patient/Procedural Factors (Group × Factor Interaction)
Exploratory analysis to determine whether the effect of RFA vs. MWA on pain is modified by patient, anatomical, or procedural factors.Interaction effect (β for interaction term) with 95% CI and p-value.Each interaction term (group × factor) tested individually in separate regression models that include both main effects and the interaction.
Time frame: Intraoperative (Day 0); using data from T2 (TLA injection) and T3 (ablation)
RFA Ablation Energy Parameters
Device-specific energy parameters for the RFA group, including number of ablation segments and temperature achieved.Number of segments (count); temperature (°C)
Time frame: Intraoperative (Day 0); recorded during the ablation phase
MWA Ablation Energy Parameters
Device-specific energy parameters for the MWA group, including power output .Power (Watts)
Time frame: Intraoperative (Day 0); recorded during the ablation phase
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Undecided
Started Sep 2026 (actual). Primary completion is estimated for Jan 2027, 4 months after the start.
Of 504 non-industry observational studies under Pain, half reached primary completion within 18 months of starting (the median), counting those still running; a quarter within 8 and three quarters within 42. This study's planned 4 months is below that.
Counting every sponsor, half of 519 studies reached it within 18 months; a quarter within 8 and three quarters within 41.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is active, not recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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Chunshui He