Efficacy of the Er:YAG Laser Debridement on Patient-Reported Pain and Bacterial Load in Chronic Wounds
Phase: NA
Conditions: Wound Open, Chronic Venous Hypertension (Idiopathic) With Ulcer, Diabetic Foot Ulcer
Sponsor: Stanford University

Efficacy of Laser Debridement on Pain and 
Bacterial Load in Chronic Wounds 
(NCT03182582) 
 
Study Protocol 
November 5, 2015 
 
Geoffrey C. Gurtner, Principal Investigator 
Stanford University 
Stanford, California 94305 
 
 

PROTOCOL SYNOPSIS 
Title 
The assessment of bio-burden reduction and procedural pain after chronic ulcer 
debridement. 
Sponsor 
Sciton, Inc. 
925 Commercial Street, Palo Alto, CA 94303 
650-493-9155 
Clinical site 
Stanford Advanced Wound Care Center 
450 Broadway Street, Redwood City, CA 94063 
650-721-8800 
Rationale 
Chronic ulcers are a significant source of morbidity and pain.  Biofilms are present in 
all chronic ulcer types.  Additional methods for safe, effective, and tolerable chronic 
ulcer bed debridement are needed. 
Study design 
Randomized-controlled cross over, open label study 
Primary objective 
To determine the efficacy of the reduction of bioburden in chronic ulcers after laser 
and sharp debridement. 
Secondary 
objectives 
To determine the tolerability of laser and sharp debridement of chronic ulcers.   
Number of 
subjects 
Twenty 
Subject selection 
inclusion criteria 
• 
Aged eighteen years or older  
• 
Having a non-healing chronic ulcer of any etiology present for at least four weeks  
• 
Willing and able to adhere to protocol requirements 
• 
Signed Informed Consent Form prior to any study related procedure 
Subject selection 
exclusion criteria 
• 
Any unstable medical condition  
• 
Documented medical history of any significant disease or condition 
• 
Documented medical history of immunosuppression 
• 
Receiving dialysis 
• 
Having osteomyelitis 
• 
Pregnancy 
• 
Participation in another clinical study involving ulcers within thirty days prior to 
enrollment 
Control 
treatment 
Sharp (scalpel or curette) debridement with standard of care 
Test treatment 
Laser debridement with standard of care 
Duration of 
subject 
participation  
Subjects will be enrolled in the study for two weeks 
Duration of study 
The total duration of the study is expected to be six weeks.   
   Recruitment and enrollment:  up to four weeks 
   Treatment:  two weeks  
Prohibited 
concomitant 
medications 
Current topical or systemic antibiotic therapy  
Efficacy 
evaluations 
Significant bioburden reduction as determined by quantitative polymerase chain 
reaction (PCR) analysis after the debridement procedures. 

Primary endpoint 
Comparison of the two treatment modalities to reduce bioburden as determined by 
quantitative polymerase chain reaction (PCR) analysis, DNA sequencing.  
Secondary 
endpoint 
Comparison of the procedural pain from the two treatment modalities as 
determined by subject reported visual analog scale (VAS) pain scores. 
Comparison of the procedural bleeding from the two treatment modalities as 
determined by physician assessment. 
Procedural bleeding 
Other evaluations Overall subject satisfaction from the two treatment modalities. 
Safety 
evaluations 
Incidence of adverse events. 
Planned interim 
analysis 
Serious adverse events will be audited by the study team on an ongoing basis 
throughout the study duration. 
Primary statistical 
analysis plan 
Treatment effectiveness will be assessed by a two-sample t-test comparing the 
evaluation criterion at the two study intervals.  
Rationale for 
number of 
subjects 
This is a pilot study to determine treatment feasibility and efficacy. 
 
SUBJECT INCLUSION CRITERIA 
A subject will be eligible for inclusion in this study if ALL of the following criteria apply: 
• 
Aged eighteen years or older  
• 
Having an ulcer of any etiology 
• 
Has signed the informed consent form prior to any study protocol related procedure 
• 
Willing and able to adhere to protocol requirements 
 
SUBJECT EXCLUSION CRITERIA 
The subject will not be eligible for study inclusion if ANY of the following criteria apply: 
• 
Any unstable medical condition that would cause the study treatment to be detrimental to 
the subject, as judged by the Principle Investigator 
• 
Documented medical history of significant cardiac, pulmonary, gastrointestinal, endocrine 
(other than Diabetes Mellitus type 1 or 2), metabolic, neurological, hepatic or nephrologic 
disease would impede the subject’s participation, as judged by the Principle Investigator 
• 
Documented medical history of immunosuppression, immune deficiency disorder, or 
currently using immunosuppressive medications 
• 
Having clinical presentation of active osteomyelitis 
• 
Pregnancy or lactation 
• 
Participation in another clinical study involving ulcers within thirty days prior to enrollment 
 
 
 
 

 
STUDY DESIGN
 
 
 
ULCER DEBRIDEMENT 
Multiple methods can be used for ulcer debridement, however evidence supporting a superior 
method is still lacking.  Sharp debridement uses scalpel, scissors, curette, or other instruments 
to remove the necrotic tissue.  Sharp debridement is the current standard of care, and produces 
rapid results.  The major drawbacks of sharp debridement include the lack of a uniform 
technique and the potential for bacterial cross contamination.  Sharp debridement may also 
result in bleeding or damage to underlying tissue structures. 
 
The method of laser debridement is based upon the well-established efficacy of laser skin 
resurfacing utilized in dermatology and plastic surgery.  The laser energy will provide controlled 
vaporization of the superficial layers of the ulcer bed.  The potential advantages of laser 
debridement include precision and uniformity of tissue ablation, reduced trauma to the ulcer 
bed, improved patient comfort, enhanced biofilm clearance, and promotion of ulcer healing.  
Anecdotally, laser debridement has shown a decrease in procedural pain scores, thereby 
facilitating a more complete debridement.   
 

Ulcers will be treated with a fully ablative erbium-doped yttrium aluminum garnet (erbium) laser 
treatment.  The erbium laser system (Sciton, Inc.) has the FDA clearance for use in surgical 
applications requiring the excision, incision, ablation, vaporization, and coagulation of soft 
tissue.   
 
The laser system is comprised of five interconnected components: 
1. Laser Console - The laser console is connected to the footswitch, the articulated arm, 
and the user screen.  The laser console houses the laser and the power supply. 
2. Footswitch - The footswitch is connected to the laser console.  Footswitch depression by 
the clinician enables laser energy delivery. 
3. Articulated Arm - The articulated arm is connected to the laser console and the 
handpiece.  The articulated arm rotates and is used to deliver the laser energy. 
4. Handpiece - The handpiece is connected to the articulated arm, and steers the pattern 
of energy onto the patient. 
5. User Screen - The user screen is connected to the console, and serves as an interface to 
allow the clinician to select different laser applications or laser treatment parameters. 
 
The laser provides precise control over the depth of ablation per pass, ranging from twenty five 
to two hundred microns.  Ablation depth is tunable in twenty five-micron increments.  The laser 
system handpiece allows the laser beam to be scanned to form two-dimensional spots onto the 
pattern size.  The range of the pattern size is 0.64 - 9.00 centimeters squared.  The handpiece 
scanner provides complete and uniform application of the laser energy.  This application will 
cover forty percent of the surface within the scanned pattern.  An aiming beam, displayed as a 
red square on the intended treatment surface, allows the clinician to visualize the treatment 
area.  The laser energy will be delivered inside this red square.  The adjoining scans will be 
delivered without gaps or overlaps to ensure even treatment.    
 
Protective eye shields to safeguard against laser light exposures will be provided to the subjects 
and personnel in treatment room.  The eye shields will remain in place until after the 
completion of the laser treatment.  The thermal destruction of tissue creates a smoke by-
product.  A smoke evacuator attached to the laser handpiece will immediately remove any 
smoke generated throughout the laser treatment.  This removal will prevent the smoke and 
debris from irritating the ulcer bed. 
 
Laser ablation will be continued until the slough tissue is completely removed.  Patient pain and 
pinpoint bleeding will represent the clinical endpoint of laser debridement.  Pinpoint bleeding 
signifies the laser energy approaching the healthy underlying tissue.  Laser debridement will be 
administered to only slough tissue and ulcer edges.  Healthy granulation tissue in the ulcer bed 
will not be laser treated.  After the completion of the laser debridement procedure, sterile gauze 
will be used to gently clean the ulcer bed to remove any remaining debris. 
 
STUDY SCHEDULE 
Screening and Enrollment (Study Week One): 
• 
Obtain signed Informed Consent Form 
• 
Review medical history to determine eligibility  
• 
Perform medical examinations needed to determine eligibility 

• 
Collect ulcer measurements and photos 
• 
Randomize patients to treatment groups  
• 
Provide subjects instructions needed for study participation 
• 
Immediately proceed to the Treatment  
 
Treatment (Study Week One): 
1.  Before debridement procedure: 
• 
Record VAS pain score, Present Pain Intensity, and Brief Pain Inventory 
• 
Collect ulcer photos and measurements 
• 
Collect biopsies 
2.  Apply anesthetic 
3.  Perform debridement procedure  
• 
Record technique or laser settings used during treatment 
4.  After debridement procedure: 
• 
Collect ulcer photos 
• 
Record VAS pain score, Present Pain Intensity, and Brief Pain Inventory  
• 
Record bleeding assessment 
• 
Collect biopsies 
• 
Provide Standard of Care  
 
Follow Up Visit (Study Week Two): 
• 
Subjects cross over to other study group 
• 
Remove ulcer dressing 
1.  Before debridement procedure: 
• 
Record VAS pain score, Present Pain Intensity, and Brief Pain Inventory 
• 
Collect ulcer photos and measurements 
• 
Collect biopsies 
2.  Apply anesthetic 
3.  Perform debridement procedure  
• 
Record technique or laser settings used during treatment 
4.  After debridement procedure: 
• 
Collect ulcer photos 
• 
Record VAS pain score, Present Pain Intensity, and Brief Pain Inventory  
• 
Record bleeding assessment 
• 
Collect biopsies 
• 
Provide Standard of Care