shevyatiwari's version from 2015-10-26 05:06


Question Answer
Mal is more hydrophilic than ALAF. MAL more lipophilic than ALA - therefore penetrates deeper
Microbdermabrasion, acetone scrubs, light chemical peels allow increased penetration of ALA/MALT
Damaged skin impairs the ability of ALA/MAL to enterF. Extensive photodamage, skin inflammation and skin abrasions or other conditions in which skin barrier is compromised all increase skin absorption vs normal skin
MAL is the prodrug of ALAT
MAL/ALA are metabolised along the haem biochemical pathwayT
MAL->ALA by hydrolysisF. By Esterases
ALA and MAL are highly fluorescentF. Non -metal bound porphyrins are highly fluorescent whereas ALA and MAL (their precursors) are NOT highly fluorescent
Skin fluorescence can be an indicator of porphyrin accumulation/clearance post ALA/MALT
Sun exposure must be avoided for 4 days post PDTF. 2 days
Peak fluorescence is determined by area of application F. Duration of application
The half life is approx 30 hours +/-10 hour in lesional and perilesional skinF. 28 +/-6 in perilesional
Neoplastic cells accumulate more porphyrins than normal cellsT. Also accumulates in sebaceous glands and the epidermis
The Soret Band is approx 311F. 410. This is the most important excitation peak of proptoporphyrin IX . it is included in Blu-U device used with ALA.
Following activation by blue/red light, ALA/MAL are excited to a high energy state which emits ROSF. Porphyrins are excited to a higher energy triplet state
Porphyrins derived from ALA are localised to the nucleusF. Mitochondira
PDT can reduce P acnesT, blue or red light alone can decrease P acnes
Blue light causes reduction in sebaceous gland sizeF. Red. RED causes a REDuction
Photoageing requires red lightF. Red or Blue
PDT can modify cytokine expressionT. Can modify cytokine expression and can induce tumour specific immune response
PDT can induce immune specific responsesT
MAL topical solution needs to be prepared just prior to application and discarded if not used in 2 hoursF. ALA
MAL can be used within 7 days of opening the tubeT
FDA indications include only Bowen'sF. Non hypertrophic AK of face and scalp, and nodular BCC or Bowen's
ALA comes in a solutionT
MAL comes in a solutionF. Comes in a cream
ALA should be used with blue lightT. AB
MAL should be used with red lightT. ALA =BLUE LIGHT , MAL - RED LIGHT
Both ALA and MAL should be applied under occlusionF. Only MAL
ALA and MAL have the same C/I'sT
ALA is C/I in those with cutaneous sensitivity at wavelengths emitted by the light source, porphyria, allergies to porphyrins, hypersensitivtiyT
MAL is C/I in porphyria, cutaneous sensitivity at wavelengths, allergic to porphyrins, and component of the creamT
MAL contains peanut and almond oilT
ALA/MAL category CT.
Lactation unknownT
CCan be used safely in kids with basal cell nevus syndromeF. Minimal experience in <18yo
Not carcinogenicT
ALA and MAL can be applied by the individual at homeF
Topical retinoids can cause increased risk of malignancyF. Increased phototoxic reactions
Regional nerve blocks are more efficacious than topical anaesthetics in relieving painT
Crusting, vesiculation and erosions are part of a normal responseT
Oedema lasts longer than erythema which lasts longer than phototoxicityF. Erythema > oedema > phototoxicity
Sunlight should be avoided for 48 hours, however artificial lights are okF. Artificial lights and cold should be avoided.
Pigmentary abnormalities can be seen sometimesT
Photosensitising drugs are potential interactionsT - increase the risk of phototoxic reactions. No specific drugs documented
Regular biochemical monitoring is required during MAL/ALAF
3 hours after MAL and 1.5 hours after ALA, wash faceT. Give supportive treatments
Chemical sunscreens are of no effect in PDTT. Chemical sunscreens do not afford protection against visible light photosensitivity due to presence of porphyrins in skin. Physical blockers may offer some protection e.g.. IRON oxide can offer some protection against blue light sensitivity induced by ALA.
Soret band is reached with blue lightT. Soret band is 410nm - most important peak for protoporphyrin 1x
Red peak is targeted with MALT

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