• E Hernández, S González, and E González.
• Laser Center, Dermatology Department, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA.
• Lasers Surg Med. 1998 Jan 1; 23 (3): 167-71.

Background And ObjectiveCurrent techniques for assessing local anesthetics (e.g., pin-prick test) cannot elicit a specific afferent activity without contamination from mechanosensitive receptors. This study was aimed to validate the use of non-scarring laser pulses as a reproducible method to assess effectiveness of topical anesthetics by comparing EMLA 5% cream and 40% lidocaine ointment.Study Design/Materials And MethodsThirty-two evaluations per compound were achieved in a total of eight healthy subjects. Non-scarring pulses from a 585 nm Pulsed-dye laser and a double-frequency Nd:YAG laser were investigated as pain inducers and the results were statistically analyzed by using a Student t-test.ResultsDiscrimination of anesthesia was better assessed with the 1,064 nm Nd:YAG laser. Anesthesia obtained by EMLA 5% cream was significantly higher than for 40% lidocaine ointment (P <0.0001). For EMLA cream, the number of evaluations with complete anesthesia was twice as much as for 40% lidocaine.ConclusionsNon-scarring laser pulses are reliable and reproductive pain inducers for assessing topical anesthetics showing a low intra-individual variation. This technique demonstrated that EMLA 5% cream is significantly more effective than 40% lidocaine ointment.

37 keywords...

hide…