RECORDING WOUNDS - DOCUMENTING WOUNDCARE

1. RECORDING WOUNDS -DOCUMENTING WOUNDCARE This Presentation gives an overview over current technical developments in the assessment of wound parameters. Part 1: Wound Measurement Techniques - an overview Part 2: Practical demonstration of wound size measurementThis Presentation gives an overview over current technical developments in the assessment of wound parameters. Part 1: Wound Measurement Techniques - an overview Part 2: Practical demonstration of wound size measurement

2. THE NEED FOR DOCUMENTATION Healing progress: - healing or not? - If not, change treatment regime as soon as poss. - detect problems (infection, blood perfusion, etc.) New clinical interventions: - new regimes, methods, treatments really better? - example: anecdotal evidence suggests that biopsy sites in chronic wounds heal faster. Is that true? Verify trials: - new bandage, ointment, debridement agent better at a certain moment in time? NOT: Prediction of healing time for chronic wounds. Healing progress: - healing or not? - If not, change treatment regime as soon as poss. - detect problems (infection, blood perfusion, etc.) New clinical interventions: - new regimes, methods, treatments really better? - example: anecdotal evidence suggests that biopsy sites in chronic wounds heal faster. Is that true? Verify trials: - new bandage, ointment, debridement agent better at a certain moment in time? NOT: Prediction of healing time for chronic wounds.

3. THE NEED FOR DOCUMENTATION (cont.) Apart from the clinical need there is also the increasing likelyhood of professional misconduct litigationApart from the clinical need there is also the increasing likelyhood of professional misconduct litigation

4. 'REAL-TIME' WOUND DOCUMENTATION Real-Time A term borrowed from computing: In this context, anything that can be done at the patient's bedside and does not require a laboratory - In contrast to laboratory techniques (biochemistry). 1. Temperature - far IR imaging, 8-12um (0.9um near IR) for Raynaud�s phenomenon, Arthritis, Paguet�s disease, wound in-flammation, blood perfusion 2. Oxygen - saturation of O2 in haemoglobin molecules (98% of O2) - tension of O2 in tissue and blood plasma (2% of O2) 3. Structure - classify wound status by tissue micro-structure using high frequency ultrasound. 4. Blood flow - ultrasound dopplers & plethysmography 5. Size - area, volume, circumference, depth of a wound - limb size: edema, underlying vascular problems 6. Colour - inflammation - wound status Protocol Extremely important for most documentation / measurement techniques in order to guarantee inter and intra observer continuity / avoid errorsReal-Time A term borrowed from computing: In this context, anything that can be done at the patient's bedside and does not require a laboratory - In contrast to laboratory techniques (biochemistry). 1. Temperature - far IR imaging, 8-12um (0.9um near IR) for Raynaud�s phenomenon, Arthritis, Paguet�s disease, wound in-flammation, blood perfusion 2. Oxygen - saturation of O2 in haemoglobin molecules (98% of O2) - tension of O2 in tissue and blood plasma (2% of O2) 3. Structure - classify wound status by tissue micro-structure using high frequency ultrasound. 4. Blood flow - ultrasound dopplers & plethysmography 5. Size - area, volume, circumference, depth of a wound - limb size: edema, underlying vascular problems 6. Colour - inflammation - wound status Protocol Extremely important for most documentation / measurement techniques in order to guarantee inter and intra observer continuity / avoid errors

5. OXYGEN MEASUREMENTS

6. 'REAL-TIME' WOUND DOCUMENTATION

7. WOUND COLOUR Prediction of Healing Time Works for certain types of burn wounds only. Presence of Inflammation (Infection ?) Under research at the moment. Wound Status Commercially available. / Value subject of discussionPrediction of Healing Time Works for certain types of burn wounds only. Presence of Inflammation (Infection ?) Under research at the moment. Wound Status Commercially available. / Value subject of discussion

8. PREDICTION OF HEALING TIME(BURN WOUNDS) Prediction of Healing Time How it works: - red, green and IR Diodes illuminate the wound site - refection picked up by a sensor - amount of relection measured and plotted Graph: Graph shows a plot of 40 wounds. The position of each wound (cross or circle) is given by plotting its Red/IR quotient over its green/IR quotient. Wounds that are likely will heal within 20 days are clustered at the top (crosses), those that won't at the bottom (circles). The probability of healing within 30 days can be expressed using the mathematical equation shown. Note: This is a rare example where the prediction of healing time is possiblePrediction of Healing Time How it works: - red, green and IR Diodes illuminate the wound site - refection picked up by a sensor - amount of relection measured and plotted Graph: Graph shows a plot of 40 wounds. The position of each wound (cross or circle) is given by plotting its Red/IR quotient over its green/IR quotient. Wounds that are likely will heal within 20 days are clustered at the top (crosses), those that won't at the bottom (circles). The probability of healing within 30 days can be expressed using the mathematical equation shown. Note: This is a rare example where the prediction of healing time is possible

9. DETECTION OF INFLAMMATION Prediction of Inflammation Based on the observation that a fully infected wound 'looks angry' at the clinician (i.e. bright reddish/purplish). The hope is, that the transition between normal colour and 'angry' colour can be detected at an early stage in order to deal with the condition as soon as possible. How it works: - images of cleansed wounds taken with digital camera - colour calibration chart included in image - image digised into HIS format (Hue, Saturation, Inensity), Hue is shown on the graph - pixels of wound added up into a histogram producing the curves shown - classification: inflamed: narrow and tall histogram, not inflamed: broad and low histogram Results: 49 out of 60 wounds classified correctly Research under way. Results in PhD Thesis end 2001Prediction of Inflammation Based on the observation that a fully infected wound 'looks angry' at the clinician (i.e. bright reddish/purplish). The hope is, that the transition between normal colour and 'angry' colour can be detected at an early stage in order to deal with the condition as soon as possible. How it works: - images of cleansed wounds taken with digital camera - colour calibration chart included in image - image digised into HIS format (Hue, Saturation, Inensity), Hue is shown on the graph - pixels of wound added up into a histogram producing the curves shown - classification: inflamed: narrow and tall histogram, not inflamed: broad and low histogram Results: 49 out of 60 wounds classified correctly Research under way. Results in PhD Thesis end 2001

10. WOUND STATUS Wound Status Value questioned by some clinicians. Underlying idea: to plot the ratio of area occupied by red, yellow and black tissue in order to follow the progress of healing over time form necrotic/sloughy towards granulating. Has been used in clinical trials (debridement by Krill enzymes) How it works: - images taken by specialised Polaroid or digital camera - images sent to CWA Institute (Sweden) for evaluation by a dermatologist using a computer program - results are sent back to clinicWound Status Value questioned by some clinicians. Underlying idea: to plot the ratio of area occupied by red, yellow and black tissue in order to follow the progress of healing over time form necrotic/sloughy towards granulating. Has been used in clinical trials (debridement by Krill enzymes) How it works: - images taken by specialised Polaroid or digital camera - images sent to CWA Institute (Sweden) for evaluation by a dermatologist using a computer program - results are sent back to clinic

11. 'REAL-TIME' WOUND DOCUMENTATION

12. TEMPERATURE MEASUREMENTS Temperatur Measurements Infrared measurements are fast and non-invasive. Care must be taken to fully understand the mechanisms that guide IR measurements (Protocol !) Factors such as emissivity of the measured surface can falsify the result if not taken into consideration. Hot wound area: inflammation Cold wound area: little perfusion, impaired healing IR Cameras: - cooled with liquid Nitrogen or by Sterling engines to minus 196 degrees take the images (modern cameras (Bolometers) are un-cooled) - expensive (� 15,000 to � 45,000) Applications: Diagnosis of rheumatism, Paguest's disease, "Vibration white finger", early detecion of Osteomyelitis due to diabetic foot ulcer (see next slide) Temperatur Measurements Infrared measurements are fast and non-invasive. Care must be taken to fully understand the mechanisms that guide IR measurements (Protocol !) Factors such as emissivity of the measured surface can falsify the result if not taken into consideration. Hot wound area: inflammation Cold wound area: little perfusion, impaired healing IR Cameras: - cooled with liquid Nitrogen or by Sterling engines to minus 196 degrees take the images (modern cameras (Bolometers) are un-cooled) - expensive (� 15,000 to � 45,000) Applications: Diagnosis of rheumatism, Paguest's disease, "Vibration white finger", early detecion of Osteomyelitis due to diabetic foot ulcer (see next slide)

13. DIABETIC FOOT ULCER Example of Infrared Imaging At admission both, and x-ray and a thermogram were taken. No pathological signs on the x-ray, but the thermogram shows clear signs of inflammation. 5 weeks later a further x-ray confirmed the underlying problem (Osteomyelitis). Clinical trial (St. Woolos Hospital, Newport) under way, results on more than 15 patients confirmed so far: Thermography can predict Osteomyelitis.Example of Infrared Imaging At admission both, and x-ray and a thermogram were taken. No pathological signs on the x-ray, but the thermogram shows clear signs of inflammation. 5 weeks later a further x-ray confirmed the underlying problem (Osteomyelitis). Clinical trial (St. Woolos Hospital, Newport) under way, results on more than 15 patients confirmed so far: Thermography can predict Osteomyelitis.

14. 'REAL-TIME' WOUND DOCUMENTATION

15. BLOOD FLOW Ultrasound Dopplers Well known in clinics, no need to explain (?) Plethysmography Constriction followed by relief of blood flow in the leg. Not without its dangers. Laser Dopplers Non-contact imaging method. Reveals blood perfusion on the surface.Ultrasound Dopplers Well known in clinics, no need to explain (?) Plethysmography Constriction followed by relief of blood flow in the leg. Not without its dangers. Laser Dopplers Non-contact imaging method. Reveals blood perfusion on the surface.

16. LASER DOPPLER IMAGING Laser Doppler Imaging Example Shows increased blood perfusion around and inside the wound. Surface measurement only (up to 2 mm deep). Measures speed of blood flow - not volume! Laser doppler imagers scan the area of interest in a process that can take up to several minutes -> patient must not move! Applications: - burn wounds - open heart surgery - inflammaory reactions - psoriasisLaser Doppler Imaging Example Shows increased blood perfusion around and inside the wound. Surface measurement only (up to 2 mm deep). Measures speed of blood flow - not volume! Laser doppler imagers scan the area of interest in a process that can take up to several minutes -> patient must not move! Applications: - burn wounds - open heart surgery - inflammaory reactions - psoriasis

17. 'REAL-TIME' WOUND DOCUMENTATION

18. TISSUE STRUCTURE High Resolution Ultrasound Reveals structure of the healing tissue. Structural complexity can be quantified by application of fractal analysis. High Resolution Ultrasound Reveals structure of the healing tissue. Structural complexity can be quantified by application of fractal analysis.

19. 'REAL-TIME' WOUND DOCUMENTATION

20. WOUND SIZE: ESTABLISHED TECHNIQUES LENGTH/DEPTH rulers AREA transparency tracings photographic methods VOLUME saline method alginate casts OTHER METHODS stereophotogrammetry ultrasound MRI scanners Kundin device These techniques are currently in use (or have been used traditionally). Most frequently used techniques are indicated by a red square. They are well documented and well understood.These techniques are currently in use (or have been used traditionally). Most frequently used techniques are indicated by a red square. They are well documented and well understood.

21. EMERGING TECHNIQUES AREA (2D) digital photography VOLUME (3D) laser scanners stereo vision structured light devices New Kids on the Block -digital cameras -computers ----> available, relatively inexpensive (??) In the following: - brief introduction into 2-D digital photographic measurement techniques - then a look at 3-D techniques and methodsNew Kids on the Block -digital cameras -computers ----> available, relatively inexpensive (??) In the following: - brief introduction into 2-D digital photographic measurement techniques - then a look at 3-D techniques and methods

22. 2D MEASUREMENTS Process: prepare wound: cleanse, reference patch take photo download onto PC use PC software to analyse photo enter in database (incl. other data) Problems: often ill defined edges (strict protocol required) flexible wounds (see this example) curvature of wound area (out of sight, geometric distortion -> wound ideally flat) Process: prepare wound: cleanse, reference patch take photo download onto PC use PC software to analyse photo enter in database (incl. other data) Problems: often ill defined edges (strict protocol required) flexible wounds (see this example) curvature of wound area (out of sight, geometric distortion -> wound ideally flat)

23. PRECISION OF 2D MEASUREMENT TECHNIQUES 2D Measurement Techniques: Precision Graph shows the precision of three groups of area measurement techniques. Precision is expressed in standard deviations as percentages of the respective area. This is necessary because the precision changes with varying wound areas. Rulers: - least precise Tracings: - more precise Photographic methods: - most precise Small wounds produce higher imprecision. Reason: quantisation error. In large wounds errors have a tendency of cancelling each other out.2D Measurement Techniques: Precision Graph shows the precision of three groups of area measurement techniques. Precision is expressed in standard deviations as percentages of the respective area. This is necessary because the precision changes with varying wound areas. Rulers: - least precise Tracings: - more precise Photographic methods: - most precise Small wounds produce higher imprecision. Reason: quantisation error. In large wounds errors have a tendency of cancelling each other out.

24. 3D MEASUREMENT METHODS 3D Measurement techniques Various tricks used to obtain a 3-D map of the wound area Laser scanners, Stereo vision Structured light 3D Measurement techniques Various tricks used to obtain a 3-D map of the wound area Laser scanners, Stereo vision Structured light

25. 3D MEASUREMENTS MAVIS Measurement of Area and Volume Instrument System developed at University of Glamorgan Stripes in colours for identification by image processing programme Stripes follow contours of the limb and the wound Computer produces 3-D map and reconstructs former healthy skin surface Wound volume sandwiched between measured and reconstructed surface MAVIS Measurement of Area and Volume Instrument System developed at University of Glamorgan Stripes in colours for identification by image processing programme Stripes follow contours of the limb and the wound Computer produces 3-D map and reconstructs former healthy skin surface Wound volume sandwiched between measured and reconstructed surface

26. PRECISION OF 3D MEASUREMENT METHODS Precision of 3-D Measurement Techniques Graph shows the precision of 5 volumetric wound measurement techniques. Precision is expressed in standard deviations as percentages of the respective volume. This is necessary because the precision changes with varying area to volume ratios. Area/volume ratio is important due to the need of reconstructing the original healthy skin surface in order to measure volume. If a wound if large and only 1mm deep, than reconstruction is difficult (a large area to interpolate) and a reconstruction error of only 1mm constitutes an error of 100%. If, in contrast, a wound is small and, say, 20mm deep, than a reconstruction error of 1mm will result in an error of only 5%.Precision of 3-D Measurement Techniques Graph shows the precision of 5 volumetric wound measurement techniques. Precision is expressed in standard deviations as percentages of the respective volume. This is necessary because the precision changes with varying area to volume ratios. Area/volume ratio is important due to the need of reconstructing the original healthy skin surface in order to measure volume. If a wound if large and only 1mm deep, than reconstruction is difficult (a large area to interpolate) and a reconstruction error of only 1mm constitutes an error of 100%. If, in contrast, a wound is small and, say, 20mm deep, than a reconstruction error of 1mm will result in an error of only 5%.

27. STEREO VISION : �3dMD�formerly: Tricorder Technology plc., UK 3dMD Picture illustrates principle well. Here an implementation with 4 cameras. Features: Observed volume quite large: 25x25x30cm fast acquisition, processing 1-3 minutes wound measurement software available evaluation: around 5 minutes not very portable Not for sale to end users. Sale via licensed manufacturers / distributors. Expected price: approx �15,000 Clinical Trial with Bradford Royal Infirmary, Dr. Rob Cameron 3dMD Picture illustrates principle well. Here an implementation with 4 cameras. Features: Observed volume quite large: 25x25x30cm fast acquisition, processing 1-3 minutes wound measurement software available evaluation: around 5 minutes not very portable Not for sale to end users. Sale via licensed manufacturers / distributors. Expected price: approx �15,000 Clinical Trial with Bradford Royal Infirmary, Dr. Rob Cameron

28. Laser Scanner: �VIVID 700� Minolta Corporation Minolta VIVID 700 portable (to a degree�..) small scanning volume: cube of 11 cm side length exports 3D files for analysis, but no wound analysis package available at present. nice price�.. ( �70,000) not dedicated for wound measurement (lack of software)Minolta VIVID 700 portable (to a degree�..) small scanning volume: cube of 11 cm side length exports 3D files for analysis, but no wound analysis package available at present. nice price�.. ( �70,000) not dedicated for wound measurement (lack of software)

29. STRUCTURED LIGHT: �MAVIS� University of Glamorgan, UK This slide shows the MAVIS instrument developed by our group at the UoG in operation. MAVIS is the acronym for Measurement of Area and Volume Instrument System. MAVIS is portable within a hospital environment measures wounds within 5 minutes provides mini database and reporting facility This slide shows the MAVIS instrument developed by our group at the UoG in operation. MAVIS is the acronym for Measurement of Area and Volume Instrument System. MAVIS is portable within a hospital environment measures wounds within 5 minutes provides mini database and reporting facility

30. STRUCTURED LIGHT: �MAVIS-II� University of Glamorgan, UK Further Development of MAVIS In collaboration with Minolta (who supply the 3-D camera) Fully portable system: 1.5 kg Expected price: approx � 5000 (max) Summer 2001Further Development of MAVIS In collaboration with Minolta (who supply the 3-D camera) Fully portable system: 1.5 kg Expected price: approx � 5000 (max) Summer 2001

31. SUMMARY Summary Every wound documentation method needs a clear protocol that gets strictly adhered to. In recent years a range measurements techniques have been developed. Competition should lead to a fall in prices. The current prices, the physical size of these devices, the time consumption, and the considerable computing skills required will mean that simple devices (rulers, tracings) will be with us for quite a while in the normal clinical setting and in the community. Watch out for digital photography. Finally remember: no measurement method is perfect: In the case of size measurement: area: 5% precision achievable (strict protocoll), volume: 10% for well defined and well shaped wounds.Summary Every wound documentation method needs a clear protocol that gets strictly adhered to. In recent years a range measurements techniques have been developed. Competition should lead to a fall in prices. The current prices, the physical size of these devices, the time consumption, and the considerable computing skills required will mean that simple devices (rulers, tracings) will be with us for quite a while in the normal clinical setting and in the community. Watch out for digital photography. Finally remember: no measurement method is perfect: In the case of size measurement: area: 5% precision achievable (strict protocoll), volume: 10% for well defined and well shaped wounds.