Photodynamic Therapy

Levulan Photodynamic Therapy (PDT)

  • “Photo” implies light, “Dynamic” implies power causing change or movement  
  • “Levulan” TM = “5 Aminolevulinic Acid” (chemical name), shortened to “ALA”, a bioidentical metabolite in the pathway leading to formation of hemoglobin in blood
  • ALA enters the epidermis (top layer of skin) where it localizes preferentially to the following kinds of cells:
    • Rapidly dividing cells
    • Bacteria, other micro-organisms
    • Inflammatory cells
    • Pre-cancer cells
    • Sun damaged, mutated cells
    • Overactive oil glands
  • The ALA waits at the cell membrane of the “undesirable” until a special light (blue or red) is allowed to penetrate through the epidermis like a sun lamp, energizing the ALA molecule in such a way to “excite it”.  The excited state ends by transferring some energy to a nearby oxygen molecule and forming an “Oxide Killer”.  All of the newly formed Oxide killers promptly attack the membranes and proteins of the nearby undesirable cells, microscopically purging the skin of the “bad guys”.       
  • For example:  Sun damage is mediated by harmful Ultraviolet rays which cause DNA mutations over our lifetime, a little here and a little there until skin  becomes visibly unhealthy.  The epidermis looks disorganized and unhealthy in the microscope of sun damaged skin, and it is here that the ALA manages to “cross over” to the inside of epidermis where it localizes to the “bad guys”, the mutated and rapidly dividing cells.  ALA is “taking position” and ready when the activating light (Blue or Red) “excites” the ALA for a short while.  But, this energy is quickly given away to a nearby Oxygen molecule which becomes an “Oxide killer”.  It turns to the “mutated problem cell” and attacks its cell membrane to death, purging the skin of a potential future skin cancer cell.  All of this is happening at a microscopic level, so not all of the benefit of the PDT is visible, rather it is healthy.  PDT prevents non-pigmented skin pre-cancers.  
  • Another example:  Acne is very difficult to treat.  “Cure” is not a term that is used in expert circles regardless of which therapy is being discussed.  Rather, “long lasting remission” is a more appropriate descriptor.   The causative mechanisms of acne are multiple, each person having their own unique set of causes.  Some, not all of the mechanisms are listed as follows:
    • higher production of oil (sebum) by sebaceous glands, triggered by androgenic hormones, especially in genetically susceptible individuals;
    • poor exfoliation of cells results in cellular debris clogs, which in turn block openings of the pores and the sebaceous glands;
    • bacterial species “move in” to this oil rich pocket at the base of the now plugged pores;
    • chemical weapons are released by the immune defenses, probably incited by the presence of irritating bacterial cells
    • The plugged pore is like a “pond”.  Everyone knows that there is no such thing as a “clean pond”.  
    • The stagnant collection of bacteria consumes the sebaceous oil leaving behind “toxic by-products” that “corrode” our good cells.  
    • Every now and then the resident bacteria and the immune system will face off and battle fiercely, enter the “pimple”.  
    • Every time there is a battle, there is further destruction of the pore, like a stretchy bag that expands but doesn’t contract anymore, eventually leading to formation of a cyst, another preferred hiding place for the bacteria.
    • Antibiotics by mouth simply stall the bacteria, but don’t clear them out.  More importantly, the antibiotics inhibit the immune chemicals, temporarily calming the battle.  Sooner or later acne returns.  
    • In the meantime, as the bacteria and immune fight wages, over the years, there is another problem. The sebaceous (oil) glands are blocked and bulging around the pore opening like a belt around a large waist.  Their presence must be diminished, in both size and function, in order to open those pore pockets and reduce the oily hiding place for the bacteria.
    • One thing is clear.  Acne is complicated.  
    • Isotretinoin (Accutane TM) is still considered the single best therapy, but this is not for everyone.  The risk / benefit ratio must be considered.  
    • Each individual has their own unique profile of factors contributing to acne.  A woman with high androgen hormones, for example, may remit simply by treating the hormonal condition.  
    • The anatomic contribution of the close quarters between bacteria and immunity is like putting cats and dogs together in a small kennel.  The pores need draining, like the pond, to encourage the bacterial vagrants to “move on”.
      • Opening the plugged pore;
      • Decompressing the entranceway sebaceous bulge;
      • Turning down the oils will discourage the bacteria.
  • More recent data analysis demonstrates precisely that the three key mechanisms of acne reduction by Photodynamic Therapy is:
    • All of the above three mechanisms.  
  • Nodulo-cystic (deep) acne started just like the others, but it became distinct by the structural damage that it caused along the way.  Underlying tissue scar, cysts, nodules are themselves a consequence and a cause of acne.  Fractionated Laser Peel injures the cysts & nodules, inducing a “repair and rebuild” process that abolishes long term plans for the bacteria in your skin.  
  • Understanding of acne has come along, but new discoveries lead to new questions. 

Acne therapy though, has advanced by modern light and laser applications such as Levulan PDT and Fractionated Laser Peels.

The Procedure

Day 0:  the day of your procedure. It takes at least three hours, half of which is relaxation as the product is “incubating” on your skin.  The initial skin preparation with glycolic, crystal microdermabrasion, and ultrasonic exfoliation is actually very enjoyable.  The application of the Levulan ALA will sting modestly for a few moments.  You will be covered with cellophane and sent out for three hours.  When you return, the red or blue light will be applied for 15 minutes, followed by a wash and home again.   

Day 1 & 2:  The skin is variably hot like a sunburn, red like a Spartan apple, and tensely swollen.  These days are photosensitive days.  You may go out for short periods to empty the garbage, but it is recommended that you remain in lower light conditions.  Most people report that you feel like you have a sunburn, while 2% say it is painful.  It is advisable to have a face fan, ice packs and Ibuprofen on hand in case of pain.   

Day 3:  The heat is gone.  The face is still somewhat swollen and now tight.  In those with acne, there will be some “whiteheads” and “pimples”.  

Day 4:  Peel, most people like a snake, others more flaky.  By this day, most people could cover with camouflage and go to work.  

Day 5 – 8:  The skin is bronzed, attractive.  It is still somewhat full in volume, and looking fine except for those who might have significant acne flare.  They will settle usually around 3 weeks.

The main preparation for this procedure is full information and understanding of process and the day to day walk through the recovery.  The recovery is uneventful with the exception of those who were not prepared for the downtime symptoms.
This is a very low risk procedure.  1% will experience a cold sore.  Call the MD to obtain oral medication should this occur.  

Manufacturer: DUSA Pharmaceuticals Inc.
Licence: #26386, Blu-U Blue Light Photodynamic Therapy Illuminator  Class: 2
Indications: The Dusa Blu-U is a Non-Laser Flourescent Blue Light Source which is used in Light Therapy in conjunction with Levulan to treat patients with Actinic Keratoses.  General treatment for Dermatological indications and treatment of Moderate Inflammatory Acne Vulgaris.