Listed below are a few of the many applications that the moorLDI2 can be used in:-

• Aesthetic Surgery and Tissue Expansion
• Port Wine Stain Treatment
• Wound Healing
• Organ Blood Flow e.g. in post-CABG heart tissue
• Venous Ulcers
• Rheumatology

Flaps

LDI 'photo' image	LDI flux image	LDI flux image

These are Laser Doppler Imager (LDI) pictures of a forearm pedicled flap (a, b) raised and (c) rotated for hand reconstruction. Blood flow is reduced after rotation.

Post-operative assessment of perfusion can be used to identify areas at risk of failure so that the causes (e.g. suture tension, kinked blood vessels) can be investigated early.

Aesthetic Surgery and Tissue Expansion

Pre-operative		Post-operative
LDI 'photo' image	LDI flux image	LDI 'photo' image	LDI flux image

Skin blood flow is reduced when it is stretched. Where there is rapid tissue expansion the perfusion can be monitored by a Laser Doppler Imager (LDI) and the expansion rate can be adjusted to avoid necrosis.

Note the reduction in perfusion post-operatively (flux changes from 'green' to 'blue').

Port Wine Stain Treatment

a previously treated b, c not previously treated	15 mins post treatment	20 mins post treatment

The skin discolouration of port wine stain haemangioma (PWS) is often reduced quite profoundly by laser treatment. The morphology of microvasculature in PWS varies widely and it would be helpful to know what colour changes can be expected before and after initial treatments.

By observing microvascular reactivity with an Laser Doppler Imager (LDI) it may be possible, in the future, to indicate the type of treatment required and make an accurate prognosis for each patient.

Images show neck of patient facing right. Note the persistance of hyperaemia at c compared with a.

Wound Healing

LDI 'photo' image	LDI flux image

The mechanisms of graft take are not fully understood. A Laser Doppler Imager (LDI) has been used here to image the perfusion of a mesh grafted wound. Note the high perfusion of underlying tissue compared with the absence of perfusion in the mesh per-operatively.

Organ Blood Flow e.g. in post-CABG heart tissue

LDI 'photo' image	LDI flux - on bypass	LDI flux - post bypass

A Laser Doppler Imager (LDI) can be used to show heart tissue blood flow (b) during and (c) after coronary artery bypass graft (CABG) surgery. The reperfusion is clearly seen and areas of poor perfusion could be identified.

Venous Ulcers

LDI flux - standing	LDI flux - patient supine

Blood flow in the lower limbs improves when the legs are raised to the horizontal. Laser Doppler imager (LDI) images from the moorLDI show improvement in skin blood flow from (a) dependent to (b) raised. This type of procedure needs further research to investigate how test responses might be used to select patient treatment and predict its efficacy.

Rheumatology

Baseline	Post cold water immersion	7.5 min recovery	15 min recovery

Laser Doppler is being used to assess and research many rheumatic diseases including Raynaud’s phenomenon, connective tissue diseases and the small joints of patients with rheumatoid arthritis. These are all non-invasive measurements using either laser Doppler monitoring or imaging.

Endoscopic laser Doppler monitor probes have been used to assess ischaemia of the small intestine in patients with systemic sclerosis. Laser Doppler imagers (LDI) has been used experimentally to assess synovial tissues of the joint capsule.

The LDI images above graphically illustrate the vasospasm of Raynaud’s phenomenon following a cold provocation.