cumulative effect of multiple passes

dovie · 10th September 2009, 03:15 AM

I was wondering if the cumulative effect of multiple passes of lesser joules equal a single pass of higher joules? i.e. does 2 passes of 10 j/cm2 = 1 pass of 20 j/cm2

Stphn · 6th November 2009, 02:50 PM

Yes, I wonder that as well. I was in a derm yesterday, asking how many passes she makes, as I have heard 3 is good, to which she replied 1-2 at most. Keep in mind this is BBL.

She said she would rather use a greater amount of energy, like 12-14 joules, and make a single pass, rather than go back over areas that have already been hit/heated, which could increase the chances of blistering.

Hope this helps/encourages someone with more knowledge and experience to comment.

Stephen

arb161 · 8th November 2009, 08:56 PM

Hi again Steph
I've had numerous multiple pass treatments with different machines. I've had no adverse side effects other than inability of my disease to respond with doctors who knew what they were doing. No blisters, no fat loss. However I have been burned and with one doctor who was listed as "best of" so bad that I was out of work for 3 weeks and have a few scars. Another doctor had the joules too high and I got a number of blisters however they were not as bad (still unacceptable) and healed without a scar. Do your homework.
Arlene

phlika29 · 9th November 2009, 07:29 AM

I dont know I am afraid but I will tell you my experience. With Dr Crouch I had lower joules/multiple passes but he was very careful to check how you had reacted to the first pass. The main problem is I cant quite remember the exact thing he did but I think he did one pass with one filter, then changed filter and did another pass and if he felt useful another pass once again with a different filter.

Have you checked his Q&A's to see what he mentions there?

phlika29 · 9th November 2009, 01:02 PM

These answers by Dr Crouch in his Q&A's may help:

T.R.I.P.L.C. Protocol

Q. Regarding IPL settings listed on http://triplc.info ("Typical Treatment Parameters"): Assuming patient responds fine to energy levels mentioned (20 to 24 J/cm²) in first treatment - do you usually go higher in subsequent sessions? If so - what steps do you make with each treatment and what would be a typical limit that should not be exceeded?

A. Thank you for the question – I am always cautious with any new patient especially if there has been no previous exposure to Intense Pulsed Light. Provided that the initial treatment has shown no signs of danger (i.e. any treatment associated redness settles down immediately) and (hopefully) some sign of improvement e.g. reduction in flushing or baseline redness, then I would discuss increasing the fluence (power) settings on subsequent treatments. The important thing to bear in mind is that some improvement at each treatment with no side effects is a worthy goal. The temptation is to increase the fluence constantly on subsequent treatments but this may just lead to a fluence that causes side effects. Generally, I think that this temptation should be resisted and this is what I advocate – provided the general trend is steady improvement then it is often best to remain improving and not risk side effects.

WrinkledClue : Hello Dr. Crouch, Thank you for taking the time to answer our questions. Do you find V-Beam or IPL more effective for treating rosacea? What, in your experience, are the advantages and drawbacks of each? Also, if you could only use one filter depth to eradicate the problematic blood vessels in rosacea skin, which one would you choose? Thanks again. -WC
Dr Peter Crouch (↑Disclaimer): Dear WrinkledClue, Thank you for your question. I use generally use Lumenis One IPL first before Pulse Dye Laser (we have an N-lite rather than a V-Beam) at our clinic. The advantages of the IPL is that it is a smoother, more feathered effect with very little downtime. Sub-purpuric (non-bruising) treatments with a pulse dye laser can be effective but normally take longer. Purpuric (bruising) treatments can be both effective and uneven as the step off in energy at the edge of the laser beam is more dramatic than with an IPL. the reason I use three filters and a triple pass with IPL is to try to target vessels at different depths and to provide a treatment which is effective and with little downtime. Traditionally, the highest fluence tolerated with the "widest" filter setting has been used to treat Rosacea. In terms of the first pass, I usually start with 590nm and progress towards 560nm and occasionally 515nm filters. If I had to use just one, it would probably be the 560nm filter. Thankfully, I am not restricted to using one filter or one pass technique and I'm happy to say that the incidence of side effects (blistering or burning) or downtime (swelling or oedema) is virtually nil using our TRIPLC protocol. I know what I would prefer when I'm treated (more gentle passes and no downtime with minimal side effects) and I think that patients should expect no less that I would choose if treating myself or a close friend or relative. By being gentle and targeting multiple vessels at different depths in a sequence of passes a few minutes apart, I hope that good clearance will result and patients can return to normal daily activities as soon as possible. I hope that the answer helps. Kind regards, Peter.