**3. Clinical demonstration: anatomical device (adjustable array)**

LINCE® accessory (fixed array) and the anatomical device (adjustable array) were designed towards meeting the clinical needs for the PDT application in the AK treatment. However, esthetics and rehabilitation procedures that use lowpower laser have been intensively studied, and more versatile devices with larger illumination areas have attracted more health professionals. The development of a device that enables the choice of wavelength is fundamental for the adoption of the appropriate procedure for a given treatment.

Two patients with a clinical diagnosis of AK were recruited to be treated with PDT using the anatomical device (**Figure 10**). The protocol applied was ALA-20% cream; incubation time 1 h 30 min; total dose 50 J/cm2 , emission at 630 ± 10 nm. After one month, no residual lesion was observed in the nose; the scalp region showed a residual lesion, which indicates an 85% elimination.

The anatomical device (adjustable array) was able to cover all extension of the lesions treated on the nose and scalp. The emission surface was leaning against the treatment region and there was no heating, which enabled the delivery of the adequate intensity.

LINCE® accessory (the 61 cm2 fixed array) was observed that excessive heating occurred when applied in contact with the treatment area, causing greater

#### **Figure 10.**

*(a) AK lesion on the nose. (b) 30 days after the PDT procedure - no residual lesion. (c) Approximately six AKs lesions scattered on the scalp region. (d) 30 days after the PDT procedure - a residual lesion.*

discomfort to the patient. This is due to its geometry of heat dissipation because it has more LEDs per area than the anatomical device (192 cm2 adjustable array). In the anatomical device, the LEDs are divided between the boards, thus obtaining a better air circulation mechanism and more heat dissipation. Therefore, the anatomical device is more comfortable for the patient and it is possible to apply it in contact with the treated area and operating at high intensity without causing excessive heating.
