• The Journal of Korean Physical Therapy
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• 제13권3호
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• pp.719-726
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• 2001

Transdermal drug delivery offers various advantages over conventional drug delivery systems, such as avoidance gastrointestinal degradation and hepatic first-pass effect. encourages patient compliance. and possible sustained release of drugs. However, transdermal transport of drugs is low permeability of the stratum corneum, the superficial layer of the skin. Many physicochemical and biological factors influencing transdermal transport is described together with the corresponding experimental and clinical results. Phonophoresis is medical treatment with drugs introduced into the skin by ultrasound energy. Enhanced drug penetration is through to result from the biophysical alterations of skin structure by ultrasound waves. The frequency used for phonophoresis is usually from 20 kHz to 15MHz. Phonophoresis can be categorized in to three ranges: low-frequency range(below 1 MHz). therapeutic frequency range(1 to 3MHz), and high-frequency range(above 3 MHz). The depth of penetration of ultrasound into skin is inversely proportional to the frequency. Cavitation may cause mechanical stress. temperature elevation, or enhanced chemical reactivity causing drug transport. One theory is that ultrasound affects the permeation of the stratum corneum lipid structure as the limiting step in permeating through the skin. The range of indications for phonophoresis is wide. Aspecific classification of the range of indications is obtained by classification of pathological conditions. The continuous research is needed for many interesting issucs of phonophoretic transdermal delivory in new future.

• 대한임상전기생리학회지
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• 제4권1호
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• pp.63-83
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• 2006

This study conducted the following experiment to examine anesthetic effects of 500 kHz ultrasound with lidocaine. Clinical experiment was conducted to compare local anesthetic effects by ultrasound frequencies and drugs with 40 normal adults and it divided subjects into experimental group (I) applying only ultrasound, ointment group (II) applying only lidocaine, phonophoresis group of 1 MHz (III), phonophoresis group of 500 kHz lidocaine (IV) for pain threshold and nerve conduct experiments. Mechanical threshold was measured with von Frey monofilament, thermal pain threshold with halogen lamp and digital thermometer, action potential in median nerve with diagnostic electromyography before and after treatment, and at 30 min., 60 min., 90 min., and 120 min. after treatment. Results of this study can be summarized as follows. Topical anesthesia experiment showed that pain threshold of phonophoresis groups was significantly increased, but there were little differences in ultrasound frequency and drugs among phonophoresis groups. Conduction anesthesia experiment showed that phonophoresis group of 500 kHz using lidocaine had significant difference in pain threshold and sensory nerve conduction compared to ointment group and ultrasound group, but there was no great difference from other phonophresis groups and light nerve block effect was found. It was considered that application of 500 kHz ultrasound using lidocaine will be more effective in deep anesthesia or nerve block than 1 MHz ultrasound. However, researches considering various frequencies, intensities and application hours in low frequency areas including kHz ultrasound are needed to increase deep permeation of drugs.

• Archives of Pharmacal Research
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• 제29권5호
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• pp.412-417
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• 2006

Triamcinolone acetonide (TA) is a corticosteroid that is used in the systemic and topical treatment of many inflammatory diseases. In this study, a phonophoretic drug delivery system was designed to enhance the TA permeability and the influence of ultrasound was examined. In order to establish the transdermal delivery system for TA, a hydrophilic carbopol gel containing TA was prepared after adopting phonophoresis. A permeation study through mouse skin was performed at $37^{\circ}C$ using a Franz diffusion cell, and the ultrasound treatment was carried out for 10 h. The level of TA permeation through the skin was evaluated under various ultrasound conditions including the frequency (1.0, 3.0 MHz), intensity (1.0, $2.5W/cm^2 $), and duty cycle (continuous, pulse mode) using a 0.5% TA gel. The highest permeation was observed under the ultrasound treatment conditions of low frequency, high intensity, and in continuous mode.

• Korean Chemical Engineering Research
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• 제46권2호
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• pp.217-221
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• 2008

다양한 초음파의 주파수와 강도 등의 물리적 인자에 대한 경피투과 촉진효과를 알아보기 위하여 lidocaine gel을 제조하고 hairless mouse의 피부를 이용하여 경피투과 촉진효과를 평가하였다. Lidocaine을 함유한 겔을 제조하여 안정성을 확인할 수 있었으며, 주파수에 따른 lidocaine의 경피투과량은 500 kHz 초음파의 경피투과량이 크게 증가하였으며, 특히 지속초음파에서 현저히 증가하였다. 초음파의 강도에 따른 lidocaine의 경피투과량은 강도가 높을수록 높게 나타났다. 500 kHz 초음파의 조사는 1 kHz에 비하여 flux를 유의성 있게 증가시켰으며, lag time을 상대적으로 지연되는 양상을 나타내었다. 따라서 현재 임상에서 가장 많이 사용하고 있는 1 kHz 초음파를 이용한 음파영동보다 500 kHz 초음파를 이용한 음파영동이 lidocaine의 투과량 증대를 위한 임상적 응용이 가능할 것으로 사료된다.