Thermal build-up, decay and retention responses to local therapeutic application of 448 kHz capacitive resistive monopolar radiofrequency: A prospective randomised crossover study in healthy adults

Figures & data

Figure 1. Graphs showing the output data as obtained from the device monitoring software. The data shown are from one participant (No. 8). The x-axis shows the monitoring sequence units (more than 1/s) and y-axis shows the parameter recorded.

Figure 2. The experimental setting with the 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) device (Indiba Activ 902), electrodes and the computer-based monitoring software.

Table 1. Demographic and mean (±SD) anthropometric data from the 15 participants who received localised 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) treatment.

	Demographic data			Mean ( ± SD) anthropometric data
No.	Mean (± SD) age (years)	Male	Female	Height (m)	Weight (kg)	Body fat (%)	Visceral fat	BMI
15	45.1 (11.6)	6	9	1.7 (0.1)	73.1 (13.1)	32.3 (8.3)	7.6 (3.4)	25.6 (3.8)

SD, standard deviation; BMI, body mass index.

Figure 3. (A) Capacitive (CAP) and resistive (RES) mode mean skin thermal responses to localised 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) treatment. The data shown (baseline, post-treatment and 45-min follow-up) are from 15 participants. *Statistically significant differences when compared to the baseline (at p < 0.05) (two-way repeated measures ANOVA). (B) Capacitive (CAP) and resistive (RES) mode individual skin thermal responses to localised 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) treatment (treated side only). The data shown (baseline, post-treatment and 45-min follow-up) are from 15 participants.

Figure 4. (A) Capacitive (CAP) and resistive (RES) mode mean skin thermal changes after localised 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) treatment (treated side). The data shown (thermal build-up, thermal decay and thermal retention) are the changes in relation to the baseline from 15 participants. *Statistically significant differences when compared to the baseline (at p < 0.05) (two-way repeated measures ANOVA). (B) Capacitive (CAP) and resistive (RES) mode individual skin thermal changes after localised 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) treatment (treated side). The data shown (thermal build-up, thermal decay and thermal retention) are the changes in relation to the baseline from 15 participants.

Figure 5. (A) Capacitive (CAP) and resistive (RES) mode mean skin thermal decay after localised 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) treatment (treated side). The data are from 15 participants, showing the decay process from post treatment to 45-min follow-up. (B) Capacitive (CAP) and resistive (RES) mode individual skin thermal decay after localised 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) treatment (treated side). The data are from 15 participants, showing the decay process from post treatment to 45-min follow-up.

Figure 6. (A) Capacitive (CAP) and resistive (RES) mode time-specific individual skin thermal responses to localised 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) treatment (treated side only). The data shown (thermal onset, definite thermal and thermal discomfort) are from 15 participants. (B) Capacitive (CAP) and resistive (RES) mode energy-specific individual skin thermal responses to localised 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) treatment (treated side only). The data shown (thermal onset, definite thermal and thermal discomfort) are from 15 participants. (C) Capacitive (CAP) and resistive (RES) mode power (peak)-specific individual skin thermal responses to localised 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) treatment (treated side only). The data shown (thermal onset, definite thermal and thermal discomfort) are from 15 participants.

Table 2. Mean time, mean energy and mean peak power reached at each of the three thermal stages for 15 participants who received localised 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) treatment.

	CAP mode			RES mode
Stage	Mean (± SD) time (s)	Mean (± SD) energy (J)	Mean (± SD) peak power (W)	Mean (±SD) time (s)	Mean (±SD) energy (J)	Mean (± SD) peak power (W)
Thermal onset	159.1 (55.2)	664.7 (405.2)	6.1 (2.3)	285.5 (109.9)	3417.3 (2299.9)	21.3 (9.6)
Definite thermal	261.5 (56.9)	1635.1 (635.3)	13.2 (3.5)	463.9 (116.2)	8867.6 (4531.4)	42.5 (16.9)
Thermal discomfort	399.7 (70.2)	4764.0 (1467.6)	32.4 (11.8)	656.0 (64.4)	19137.5 (5087)	81.5 (20.1)

SD, standard deviation.

Table 3. Electrode (active) temperature at various times and intensity of application during localised 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) treatment. The study was conducted on a single male participant, aged 37 years (body mass index, 23) at room temperature 25 °C and humidity 66%.

CAP mode temperature (^oC)				RES mode temperature (^oC)
Intensity in percentage (device PP is 450 VA)	At 3 min	At 6 min	At 9 min	Intensity in percentage (device PP is 200 W)	At 3 min	At 6 min	At 9 min
19	30.2	31.4	31.7	11	27.9	28.1	28.6
31	31	32.5	33.2	22	29.4	30.3	30.7
40	33.4	34.3*	36.2*	32	30.9	30.9*	32.8*
67^#	35.7**	XX	XX	40^#	32.8**	XX	XX

PP, peak power; VA, volt-ampere; XX – not measured due to thermal discomfort to the participant.

^#Mean peak power obtained from 15 participants during the CAP and RES modes of the main experiment.

*Moderate heating reported by the participant.

**High heating reported by the participant.