Evaluation of optical imaging in foot ulcer management

ISRCTN ISRCTN50978600
DOI https://doi.org/10.1186/ISRCTN50978600
IRAS number 331195
Secondary identifying numbers CPMS 68419, IRAS 331195
Submission date
07/06/2024
Registration date
19/07/2024
Last edited
20/01/2025
Recruitment status
No longer recruiting
Overall study status
Ongoing
Condition category
Skin and Connective Tissue Diseases
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year

Plain English summary of protocol

Background and study aims
Non-healing foot wounds (ulcers) are frequent and lead to poor quality-of-life with high risk of amputation and mortality. A major reason for wounds not to heal are blocked arteries in the legs. Currently, the standard test to measure the blood flow in the legs is called ankle brachial pressure index (ABPI) and it requires blood pressure measurement with a cuff at the ankle. However, ABPI is not frequently performed, may miss diagnoses, and does not measure blood flow in the foot where ulcers are.
Optoacoustic imaging (OAI) and photoplethysmography (PPG) are 2 new non-invasive methods that can use light to measure oxygen and blood flow through the skin, but these have not been tested in patients with ulcers.
The aim of the study is to evaluate the value of OAI and PPG in patients with foot ulcers. We hypothesize that OAI and PPG can provide additional important clinical information otherwise not available.

Who can participate?
All patients with foot ulcers scheduled for routine appointments in the multidisciplinary diabetic foot and vascular clinics at East Surrey Hospital.

What does the study involve?
OAI and PPG scans will be performed at several sites along the leg and foot in addition to standard investigations. In those patients that will undergo surgery to improve blood flow as part of usual care, we will repeat all measurements after surgery. We will collect the results of the standard investigations and baseline medical and sociodemographic characteristics and collect 1 year outcome data based on electronic patient records.

What are the possible benefits and risks of participating?
There are no direct benefits to patients. The results will help vascular doctors to evaluate the value of OAI and PPG and if they can provide additional important clinical information otherwise not available.

Where is the study run from?
East Surrey Hospital (Surrey and Sussex Healthcare NHS Trust), Redhill with the University of Surrey (Department of Clinical and Experimental Medicine), Guildford (UK)

When is the study starting and how long is it expected to run for?
December 2023 to March 2026

Who is funding the study?
The study is funded by iThera Medical and Medical Research Council (UK)

Who is the main contact?
Prof. Christian Heiss, c.heiss@surrey.ac.uk

Contact information

Prof Christian Heiss
Public, Scientific, Principal Investigator

University of Surrey
Leggett building
Guildford
GU2 7XH
United Kingdom

ORCiD logoORCID ID 0000-0002-3212-8995
Phone +44 (0)1483 686693
Email c.heiss@surrey.ac.uk

Study information

Study designSingle-centre prospective observational cross-sectional pilot study
Primary study designObservational
Secondary study designCross sectional study
Study setting(s)Hospital
Study typeDiagnostic
Participant information sheet 45586 PIS V01 12-06-2024.pdf
Scientific titleEvaluation of optoacoustic imaging and photoplethysmography in patients with foot ulcers: a cross-sectional pilot study
Study acronymOAI-1
Study objectivesOptoacoustic imaging (OAI) and photoplethysmography (PPG) can provide additional important clinical information that is otherwise not available.
Ethics approval(s)

Approved 10/07/2024, South Central - Oxford C Research Ethics Committee (2 Redman Place, Stratford, London, E20 1JQ, United Kingdom; +44 207 104 8271; oxfordc.rec@hra.nhs.uk), ref: 24/SC/0242

Health condition(s) or problem(s) studiedFoot ulcers
InterventionPatients with ulcers will be prospectively recruited in the multidisciplinary diabetic foot and vascular clinics. Optoacoustic imaging (OAI) and photoplethysmography (PPG) scans will be performed at several sites along the leg and foot in addition to standard investigations (ultrasound, ABPI, toe pressure) and baseline medical and sociodemographic characteristics. Some patients will undergo surgery to improve blood flow as part of usual care. In these patients, the researchers will repeat all measurements after surgery. They will collect 1 year outcome data (wound healing, amputation, mortality) based on electronic patient records.
Intervention typeOther
Primary outcome measure1. Tissue oxygenation and blood flow measured using optoacoustic imaging in feet at baseline (all) and after angioplasty (subgroup that receives angioplasty as standard of care)
2. Blood flow measured using photoplethysmography in feet at baseline and after angioplasty (subgroup)
Secondary outcome measures1. Ankle brachial pressure index measured using ankle Doppler based estimated ABPI (eABPI) at baseline and after angioplasty (subgroup)
2. Toe brachial pressure index measured using arterial plethysmography with cuff at baseline and after angioplasty (subgroup)
3. Peripheral vascular disease in lower extremity arteries measured with duplex ultrasound at baseline and after angioplasty (subgroup)
4. 1-year outcome (major amputation, death, revascularisation, wound healing) measured using electronic patient records over 1 year
Overall study start date04/12/2023
Completion date01/03/2026

Eligibility

Participant type(s)Patient
Age groupAdult
Lower age limit18 Years
SexBoth
Target number of participants40
Key inclusion criteria1. Age 18 years or greater
2. Non-healing foot wound for at least 4 weeks despite wound care
3. Scheduled for/referred to routine vascular assessment, multidisciplinary foot team clinic or endovascular revascularisation
4. Willing and able to provide informed consent
5. Vascular ultrasound exam required including Ankle Brachial Pressure Index (ABPI) and Toe Brachial Index (TBI)
Key exclusion criteria1. Heart failure New York Heart Association (NYHA) ≥3
2. Systemic inflammation
3. Critically ill, American Society of Anesthesiologists (ASA) IV
4. Extensive foot wounds making OAI scanning impossible
5. No toes to measure TBI
6. Leg wounds or skin conditions preventing ABPI, OAI or ultrasound investigations
7. Participants who are unable to wear the laser safety goggles
8. Tattoos in the field of view for OAI scanner
9. Currently under phototherapy
10. History of photosensitising disease (e.g. porphyria, Lupus erythematosus)
11. Experiencing photo-toxicity associated with currently taking or having taken photosensitizing agents within the previous 72 h (e.g. sulfonamides, ampicillin, tetracycline, doxycycline)
12. Pregnancy
Date of first enrolment18/12/2024
Date of final enrolment31/03/2025

Locations

Countries of recruitment

  • England
  • United Kingdom

Study participating centre

Surrey and Sussex Healthcare NHS Trust
Trust Headquarters
East Surrey Hospital
Canada Avenue
Redhill
RH1 5RH
United Kingdom

Sponsor information

University of Surrey
University/education

Assurance Team – Research, Innovation and Impact
Senate House
Guildford
GU2 7XH
England
United Kingdom

Phone +44 (0)1483 683490
Email rigo@surrey.ac.uk
Website https://www.surrey.ac.uk/faculty-health-medical-sciences/research/research-and-innovation-team
ROR logo "ROR" https://ror.org/00ks66431

Funders

Funder type

Industry

iThera

No information available

Medical Research Council
Government organisation / National government
Alternative name(s)
Medical Research Council (United Kingdom), UK Medical Research Council, MRC
Location
United Kingdom
European Association of National Metrology Institutes
Private sector organisation / Associations and societies (private and public)
Alternative name(s)
EURAMET e.V., European Collaboration in Measurement Standards, EUROMET, EURAMET
Location
Germany
UK Research and Innovation
Government organisation / National government
Alternative name(s)
UKRI
Location
United Kingdom

Results and Publications

Intention to publish date01/02/2026
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryData sharing statement to be made available at a later date
Publication and dissemination planThe results of this study will be submitted for publication in peer-reviewed journals and presented at relevant conferences. The researchers plan to publish the anonymised data in a publicly accessible repository (e.g. UK data archive). This is stated in the patient information sheet and consent form. A lay summary will be sent to participants who indicate they would like to receive this.
IPD sharing planThe data-sharing plans for the current study are unknown and will be made available at a later date

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Participant information sheet version 01 12/06/2024 12/07/2024 No Yes

Additional files

45586 PIS V01 12-06-2024.pdf

Editorial Notes

20/01/2025: The recruitment end date was changed from 01/02/2025 to 31/03/2025.
17/01/2025: The recruitment start date was changed from 01/09/2024 to 18/12/2024.
19/07/2024: The recruitment start date was changed from 01/07/2024 to 01/09/2024.
12/07/2024: Trial's existence confirmed by South Central - Oxford C Research Ethics Committee.