OBJECTIVETo evaluate the transdermal permeability of glucosamine sulfate solution across ex vivo rabbit dermis under ultrasound and optimize the ultrasound conditions.

METHODSThe ultrasound-assisted transdermal permeation of glucosamine sulfate solution across ex vivo rabbit dermis was tested using a simple Franz diffuse. The transdermal permeation volume and rate were calculated by measuring the concentration of glucosamine sulfate in the receptor fluid with ultraviolet spectrophotometry, and the impact of different sound intensities, irradiation time and solution concentration on solution permeation was analyzed.

RESULTSAt the ultrasound intensity of 0.2 W/cm(2), the permeation volume and rate of glucosamine sulfate both reached the maximum; no glucosamine sulfate was detected in the receptor fluid after a 5-min ultrasound irradiation. The permeation volume and rate of glucosamine sulfate increased as the irradiation time prolonged and also with increased glucosamine sulfate concentration. The dorsal and lateral skin thickness (2.0∓0.1 and 1.2∓0.1 mm, respectively) did not significantly affect the transdermal permeation of glucosamine sulfate (P>0.05).

CONCLUSIONUltrasound irradiation at 1.0 MHz for over 5 min allows glucosamine sulfate to permeate rabbit dermis, and the volume and rate of permeation increase with the irradiation time and concentration of the solution and are not affected by variations of the dermal thickness.

Administration, Cutaneous ; Animals ; Dermis ; diagnostic imaging ; drug effects ; Glucosamine ; metabolism ; In Vitro Techniques ; Permeability ; Rabbits ; Skin Absorption ; Ultrasonics ; Ultrasonography

OBJECTIVETo study the value of dynamic contrast-enhanced magnetic resonance imaging (MRI) in evaluating the curative effect of high intensity focused ultrasound (HIFU) for hypersplenism.

METHODSA retrospective analysis of dynamic contrast enhanced MRI data was conducted in 15 patients with hypersplenism before and after HIFU treatment to observe the signal changes and enhancement features of the lesions.

RESULTSCompared with that before treatment, the signal intensity of the lesions after HIFU could be increased, reduced or remained unchanged on T(1)WI without specificity; on T(2)WI, the signal intensity of the lesions was reduced after HIFU treatment. Dynamic contrast-enhanced MRI showed larger ablation areas than those displayed by T(1)WI and T(2)WI, and no enhancement was found in the lesions.

CONCLUSIONT(2)WI has a greater specificity in demonstrating coagulation necrosis of hypersplenism after HIFU ablation, and dynamic contrast-enhanced MRI has a higher sensitivity in displaying the ablation area by highlighting the blood supply and enhancement characteristics of the lesions. MRI is efficient and noninvasive in follow-up evaluation of the signal intensity as well as histological changes of the treated region after HIFU.

Adult ; Aged ; Female ; High-Intensity Focused Ultrasound Ablation ; Humans ; Hypersplenism ; diagnosis ; therapy ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Retrospective Studies ; Treatment Outcome