Evidence of Burn Assessment Accuracy obtained with the aid of LDI

The benefits of the laser Doppler technique were first recognised by surgeons using the original contact technique whereby fibre optic probes in contact with the skin informed of the blood flow at single or multiple points, with or without the added stimulus of local heating (e.g. Alsbjorn et al, 1983). The advent of laser Doppler Imaging for assessing burn wounds (Niazi et al, 1993) demonstrated the advantages and early accuracy of this non-contact technique, confirmed by many studies since:

An audit of the use of LDI in the assessment of burn depth, by Pape et al. (2001), reported 97% accuracy with LDI compared to 60-80% accuracy for established clinical methods. This study also found that use of LDI enabled unnecessary surgery to be avoided, resulting in a reduction of both costs and workload.

A study in children by Holland et al (2002) included 57 patients with a mean age of 1 year and 10 months; aided by LDI to determine deep partial and full thickness burns they achieved an accuracy of 90% compared with 66% by clinical assessment alone; for superficial partial thickness burns the rates were 96% and 71%, respectively. In a further study at this Burn Centre (La Hei, 2006) they found that accurate assessments (97%) could be made independent of clinical examination.

Jeng et al. (2003) reported that use of LDI enabled earlier and more objective determination of the need to excise and graft burns and found that use of LDI saved a median of 2 days for a 100% accurate assessment of burn depth by visual interpretation of LDI images.

La Hei et al (2006) found an overall accuracy of 97% when the accuracy of reporting on 50 LDI scans each by two clinicians was compared with actual burn wound outcome. No superficial dermal burns were incorrectly predicted to take longer than 14 days to heal.

Ng et al (2007) reported that accurate LDI assessments can be achieved post application of Flammacerium provided the dressing is kept moist so that it can be removed for LDI imaging.
 
Hoeksema (2009) studied the accuracies on different days post burn comparing predictions made with the aid of LDI and by clinical assessment alone in 40 patients; assessment were made on day of burn and days 1, 3, 5 and 8 post burn; accuracies found for LDI-aided assessment were 54%, 79.5%, 95% , 97% and 100% compared with clinical accuracies of 40.6%, 61.5%, 52.5%, 71.4% and 100%, respectively. Differences were highly significant at days 3 and 5 post burn (p<0.001 and p<0.005, resp). Within these findings: clinically, 47% of wounds predicted as superficial on day 0 were found to be deep; 77% predicted to be deep on day 0 were found to be superficial; corresponding day 0 predictions for LDI were 35% and 57%, indicating, by both techniques, that more wounds ‘convert’ from deep to superficial than ‘convert’ to deeper wounds.

A statistical analysis of data from a multi-centre study demonstrated that once LDI skin blood flow was known only gender made a small contribution (2%) to the accuracy of healing time prediction; other parameters (age, %TBSA, site, cause) made no significant contribution (Baker et al, 2009).

Pape et al, 2012, conducted a multi-centre, international clinical study to define LDI ranges for burn wound healing potential prediction; Monstrey et al, 2012 validated the colour coding using these ranges for LDI image interpretation and found an accuracy of 96% (433 burn wounds).

NICE is the UK National Institute for Health and Clinical Excellence. It has assesses the evidence for use of the moorLDI2-BI and in 2011 recommended its use: ‘NICE has said that the moorLDI2-BI can be used to help make decisions about treatment in patients when experienced healthcare professionals aren’t sure about how deep the burn wound is or how long it might take to heal. Hospital teams may want to use the moorLDI2-BI because the evidence showed that decisions about whether to use surgery could be made earlier, meaning less time spent in hospital. It could also reduce the size of areas that are operated on, or avoid the need for surgery completely in some patients who otherwise might have had to have surgery.’

References

Alsbjorn B, Micheels J, Sorensen B. Laser Doppler flowmetry measurements of superficial dermal, deep dermal and subdermal burns. Scand J Plast Reconstr Surg, 1984, 18; 75-79.

Baker RD, Weinand C, Jeng JC, Hoeksema H, Monstrey S, Pape SA, Spence R and Wilson D. 2009. Using ordinal logistic regression to evaluate the performance of laser-Doppler predictions of burn-healing time. BMC Medical Research Methodology 2009, 9:11.

Hoeksema H, Van de Sijpe K, Tondu T, Hamdi M, Van Landuyt K, Blondeel P, Monstrey S. 2009. Accuracy of early burn depth assessment by laser Doppler imaging on different days post burn. Burns. Feb;35(1):36-45.

La Hei ER, Holland AJ, Martin HC. 2006 Laser Doppler imaging of paediatric burns: burn wound outcome can be predicted independent of clinical examination. Burns. 32: 550-3.

Monstrey S.M, Hoeksema H, Baker R.D. et al 2011. Burn wound healing time assessed by laser Doppler imaging (LDI) Part2: Validation of a dedicated colour code for image interpretation. Burns 2011 37 249–256.

Ng D., Tay S, Booth S, Gilbert PM, Dheansa BS. 2007. The use of laser Doppler imaging for burn depth assessment after application of flammacerium, Burns. 2007 May;33(3):396-7.

Niazi Z B M, Essex T J H, Papini R, Scott D, McLean N R, Black M J M. New laser Doppler scanner, a valuable adjunct in burn depth assessment. Burns, 1993, 19; 485-489.

NICE. MoorLDI2 Burns Imager a laser Doppler blood flow imager for the assessment of burn wounds (MTG2).

Pape, S.A. Baker, R. D. Wilson, D. Hoeksema, H. Jeng, J.C. Spence, R.J. Monstrey, S (2012) Burn wound healing time assessed by laser Doppler imaging (LDI). Part 1: Derivation of a dedicated colour code for image interpretation Burns, Burns, 38, p187-94.

Jeng, J C. Clarke, T J. Bridgeman, A. Shivnan, L. Thornton, PM. Alam, H. Clarke, TJ. Jablonski, KA. Jordan, M H (2003) Laser Doppler Imaging Determines Need for Excision and Grafting in Advance of Clinical Judgement: A Prospective Blinded Trial. Burns. 29 p665–670.

Holland, AJ. Martin, HC. Cass, DT (2002) Laser Doppler imaging prediction of burn wound outcome in children. Burns. 28(1) p11–17.