Can MTZ Lines Be Permanent with the Profractional XC Laser?

What are MTZ lines? Is it true that if the Profractional XC laser creates to many mtz's (holes) and seals the vessels that no blood flow = dead cells? And if the laser goes too deep or to many passes are done in one spot can it cause cell death or damage the cells needed to create/renew new ones? I am 2 wks,3 days out from having Profractional XC laser and I have these white lines (made up of tiny holes) all over my face and my skin looks aged and dead.I'm devastated! Are the lines permanent?

Doctor Answers 2

What is the healing process after Profractional XC laser resurfacing

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A technical explanation before I answer your question:

Fractional laser resurfacing vaporizes tiny columns of skin within a certain area.  The amount of skin vaporized ranges from 5% to 30% of the surface area treated.  The depth of treatment ranges from 25 to 1500 micrometers.  Consider that the epidermis (top layer of the skin) is approximately 100 micrometers, so in order to get to the dermis to have an effect on removing wrinkles or scars and on new collagen production, one has to set the laser to go deeper than 100 micrometers (or microns).

After those tiny columns of skin are vaporized, the skin begins the repair process.  First it tightens around the vaporized areas, then, because the treatment is actually a wound to the skin, the fibroblasts (cells that make collagen) start making new collagen to heal the wound.

It is absolutely essential to keep the skin moisurized with an occlusive moisturizer like Aquaphor for 4-5 days after Profractional resurfacing.  The skin heals best if it is moist, as dry crusts prevent the skin cells from reaching out to each other.

I suspect that it was lack of intensive moisturization that made your skin look and feel the way it does.  I recommend using a bland moisturizing cream made for sensitive skin twice a day for the next week or so.  Also, make sure that yu are using a broad spectrum sunscreen with a high SPF when you go outside.

It is not possible to cause enough cell death with the Profractional, so that the skin cannot create new ones.  The settings on the laser will not allow you to do that.  However, it does take a longer time to recover if the resurfacing was deep, but it also gives you greater results.  Use a moisturizer and sunscreen, and if you can, post a photo to see how you are doing.

Short Hills Dermatologic Surgeon

Yes, they can be permanent, but the majority fade with time.

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In short- Yes. I have seen and fixed permanent MTZ lines from ProFractional and other fractional lasers. I usually leave these lines to self resolve for a period of 12 months, and if they do not, I will discuss with the patient various options for removal. I have had 2 cases referred from other clinics to me for 'fixing up.' The first thing is that it is no fault of the laser specialist who performed the procedure. 
The vast, vast majority will fade within 6 months. 
If they don not fade, then the use of fully ablative laser (eg. Erbium resurfacing and or CO2) will fix it up. The downtime following full ablation is about 10 days, but to date, the results have been 100% successful. 


Dr Davin Lim
Laser Dermatologist

These answers are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.