Takao Shibaji

A mechanism of the high frequency AC iontophoresis

The efficiency and the voltage dependence of the AC iontophoresis were studied in vitro. Two cylindrical glass cells separated by a cellophane film were used, where the donor cell was filled with the solution of target electrolytes and the receptor cell with distilled water. The sinusoidal AC voltage with a frequency of 1 kHz was applied between the two platinum plates located at the opposite ends of two cells. The time variation of the ion concentration was evaluated by measuring the impedance of the solution in the receptor cell. The transportation velocity of the ions increased with the amplitude of the voltage applied between two platinum plate electrodes apart 20 mm up to approximately 15 V, and leveled off above approximately 15 V. A theoretical model is proposed on the AC iontophoresis, where each ion moves together with the surrounding water molecules when it is hydrated. The effective Stokes radius of an ion is assumed to be half of the whole size of the ion with hydrating water molecules. When the external alternating electric field strongly vibrates the ion, the ion-dipole interactions between the ion and water molecules are broken, resulting in the reduced effective Stokes radius, which leads to the increase of the diffusion efficiency.

Application of a mandibular nerve block using an indwelling catheter for intractable cancer pain

We report a case in which a mandibular nerve block using an indwelling catheter was employed for pain management in a terminal case of orofacial cancer.

Lidocaine transport through a cellophane membrane by alternating current iontophoresis with a duty cycle

The purpose of this study was to determine whether lidocaine can be efficiently transported across a cellophane membrane using a square-wave alternating current (AC) with an adjusted duty cycle. Three voltages at 1 kHz with 6 duty cycles were applied for 60 min to the diffusion cells on both sides of the cellophane membrane. The donor chamber was filled with 1% lidocaine hydrochloride solution. The transport of lidocaine was enhanced in a voltage-, and duty cycle-dependent manner. These findings indicate that voltage and the direct current (DC) component of the square-wave AC play important roles in generating the driving force necessary for lidocaine delivery. Additionally, the periodic polarity alteration could reduce the electrode polarization. The higher voltages and duty cycles induced a pH change. The practical electrical conditions which are preferable for clinical application were 10 V with a 70% duty cycle or 20 V with a 60% duty cycle.

481 A RETROSPECTIVE STUDY OF 915 CASES WITH ATYPICAL FACIAL PAIN

back and finally an urge for changing body position in 13/15 mothers of group B, but none of A. Conclusion: The surgical technique appears to trigger pain awareness. Maximum quality of anaesthesia can be achieved with HB. HB is simple and acts rapidly allowing safe and quick launch of CS when no extraabdominal handlings are performed. The unpleasant sensation appears to result from such handlings and could attribute to peritoneal irritation via traction. Sufficient anaesthesia was achieved without raising the Spinal Anaesthesia Level (SAL) to the usually recommended C4 causing total sympathetic block. Since some painfull sensation still exists in 50% of mothers even at C4. The limited spread of HB appears to lead in more sufficient short-term post-operative anaesthesia.

829 EFFECT OF PRETREATMENT OF THE SKIN FOR AC IONTOPHORESIS

Objective: To investigate the efficacy of low intensity ultrasound therapy (US), a conservative option of treatment of mild to moderate carpal tunnel syndrome (CTS). Material and Method: Nineteen patients, with unilateral CTS confirmed by electromyographic examination were included. Patients were randomly assigned to US (10 hands) and placebo group (9 hands). Ultrasound therapy, with intensities of 1.5W/cm2 US group, and 0.0W/cm2 placebo group was applied once a day to palmar carpal tunnel area for 5 minutes, 5 days a week, for 2 weeks. Clinical assessments were performed at baseline, at the end of the treatment. Patients were evaluated with clinical parameters, as functional status scale (FSS), visual analog scale (VAS), symptom severity scale (SSS), and grip-strength. Electrophysiologic examination were performed of all hands. Results: Clinical and electromyographic parameters, were similar at baseline in both groups. In the US group and placebo group, significant improvement were observed in VAS (p< 0.001, p< 0.01 respectively) and SSS (p< 0.001, p< 0.05 respectively) after treatment. At the posttreatment, significant improvements were found in the FSS, grip-strength sign in only US group. When compared two groups showed significant improvement in VAS (p< 0.001) and SSS (p< 0.001) in favor of US group after therapy. There were not statistically significant improvements in motor and sensory distal latencies. Conclusion: Our results indicated that of US and placebo US theraphy are effective on pain and clinical symptoms in CTS, we to considered that US is much more effective on pain, clinical symptoms and functional status in patients with CTS.