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we are at an exciting time in the evolution of acne therapy , as many new advances are providing positive results for our patients .
lasers and light sources have become a useful addition to our therapeutic armamentarium for acne vulgaris .
the use of intense pulsed light ( ipl ) may further enhance the benefits of these devices .
we conducted this study to compare the burst - pulse and single - pulse modes in ipl for treating acne vulgaris and to study the efficacy of ipl in treating acne vulgaris .
they were subjected to monotherapy with ipl ( v care medical systems private limited , bangalore , karnataka ) .
patients who were taking oral or topical antiacne medications before reporting to us were excluded from the study .
baseline grading of acne was done with michelsons acne severity index ( number of comedones , papules , pustules , infiltrated and cystic lesions are counted .
severity index is 0.5 for comedones , 1 for papules , 2 for pustules , 3 for infiltrated lesion , and 4 for cystic lesions . multiplying each type of lesion with its severity index and adding score together
give the final score ) however , right side and left side of face were scored separately and a total score was also noted .
starting dose was 1 j less than the most tolerable dose , which varied among the patients .
the lowest fluence used for treatment on the face was 15 j , and the maximum fluence used was 21 j and 420 nm cutoff filter was used for the study .
ipl was administered once a week for 4 weeks , and the fluence was increased by 1 j every session .
right side of the face was subjected to burst - pulse mode , and the left side was subjected to single - pulse mode .
the ipl parameters were : auto mode , skin type 4 , pulse width 12 ms , single - pulse mode for left side of face and burst - pulse mode ( five pulses and pulse delay 6 ms ) for right side of face .
severity index was calculated after four sessions , and digital photographs were taken at the baseline and after four sessions for comparison .
the mean baseline score was 22.4 for single - pulse mode , which showed 40.17% reduction after four sessions [ figures 1 and 2 ] .
the mean acne severity score at baseline was 27 for burst - pulse mode and showed 56.66% reduction after four sessions [ figures 3 and 4 ] .
burst - pulse treated side showed a better control than the single - pulse treated site .
[ figures 5 and 6 ] the mean total score was 49.4 at baseline and showed 49.19% reduction after four sessions of ipl [ table 1 ] .
table 2 shows the total score at the baseline and after four sessions of ipl .
total score showed statistically significant improvement after four sessions of ipl ( sd = 4.5351 , critical t - value = 2.2622 , t value = 5.3693 ) .
the improvement in severity score on burst - pulse mode treated side was statistically significant ( sd = 3.0433 , t - value = 5.0439 ) .
severity score of single - pulse mode treated side also showed significant improvement ( sd = 1.9621 , t - value = 4.5868 ) . before treatment ( single - pulse mode ) after treatment ( single - pulse mode ) before treatment ( burst - pulse mode ) after treatment ( burst - pulse mode ) burst - pulse treated site after four sessions single - pulse treated site after four sessions acne severity score for single- and burst - pulse modes acne severity score - total score for full face
ipl technology involves application of a noncoherent , nonlaser broadband , filtered flash lamp source directed to the skin . modifications of various parameters allow flexibility in treatment , which include wavelength , energy fluence , pulse duration , and pulse delay .
propionibacterium acnes ( p. acnes ) produces the porphyrins during their growth and proliferation in the follicular units .
these porphyrins have an absorption spectrum that is in the near ultraviolet ( uv ) and visible spectrum of light .
the major absorption peak for these porphyrins is at 415 nm , known commonly as the soret band .
a second major peak , seen at 630 nm , is also visible in the absorption spectrum , which corresponds to red light .
therefore , phototherapy devices have been developed that utilize either blue light or red light pdt for the treatment of inflammatory acne vulgaris lesions .
the pdt process seen in this reaction involves the photoexcitation of the p. acnes porphyrins after exposure to the appropriate light source .
this will then form singlet oxygen within the microorganism itself , resulting in the selective destruction of the bacteria .
the reaction occurs rapidly and has been observed in vivo.[13 ] a variety of ipl sources have been used to treat acne vulgaris .
treated 19 patients with ipl and showed that 85% of the individuals had a > 50% improvement in their acne vulgaris lesions following twice weekly therapy for 4 weeks .
dierickx reported on the lux v handpiece from the palomar medical technologies ipl systems ( estelux , medilux , and starlux systems ) .
fourteen patients with mild - to - moderate inflammatory acne vulgaris lesions received five treatments that were administered every 24 weeks . at 6 months post - therapy , clearance rates of 72% for noninflammatory acne vulgaris lesions and 73% for inflammatory acne vulgaris lesions
reported 50% reduction in inflammatory acne vulgaris with ipl - cleartouch / skinstation ( radiancy , orangeburg , ny , usa ) .
ipl technology works in single- and burst - pulse modes . in the single - pulse mode
, the fluence will be delivered in single shot , whereas in burst - pulse mode fluence is divided into series of pulses with a delay between the pulses .
we found 49% reduction in the acne severity score with weekly ipl monotherapy after four treatments .
both the modes showed a reduction in acne score , but burst - pulse mode ( 56% ) showed a better clearance than the single - pulse mode ( 40% ) .
ipl as a monotherapy leads to significant acne clearance , and burst - pulse mode ( five pulses , 6 ms pulse delay ) was better than single - pulse mode in our study . combining ipl with topical and systemic medications
since our sample size was small , further studies with a large sample size are required to establish these findings .
background : intense pulsed light ( ipl ) has been used for the treatment of facial acne . 
 modifications of various parameters allow flexibility in treatment , which include energy fluence , pulse duration , and pulse delay . 
 we compared the efficacy of burst - pulse ( multiple pulse ) mode with single - pulse mode in treatment of acne.objective:this study was designed to evaluate the efficacy of the ipl in treatment of facial acne and to compare burst - pulse and single - pulse mode in treatment of acne.materials and methods : ten patients with facial acne were subjected to monotherapy with ipl . 
 baseline grading of acne was done with michelsons acne severity index ; however , right and left side of face were scored separately and a total score was also taken . 
 ipl was administered once weekly for four sessions . 
 right side was subjected to ipl with burst - pulse mode , and left side was subjected to single - pulse mode . severity score assessed after the end of treatment . 
 clinical photographs were also obtained for evaluation.results:all patients revealed a reduction in number of acne for both single- and burst - pulse mode treated sides . 
 the mean total score was 49.4 at baseline and showed 49.19% reduction after four sessions of ipl . 
 burst - pulse mode treated side showed a better control than that of single - pulse mode.conclusion:ipl as a monotherapy showed beneficial effect in treatment of facial acne . 
 burst - pulse mode was better than the single - pulse mode in clearing acne .