TUSSUE CLEARANCE - A CRITICAL EVALUATION OF ITS POTENTIAL IN DERMATOLOGIC INVESTIGATION

[摘要] The present study utilized the tissue clearance technic to determine the parameters for the study of the nutritional circulation of the skin. Definite criteria were established and, when they were strictly adhered to, resulted in consistent and reproducible results. It was established that the clearance rates for skin are independent of the volume of material injected for the range of volumes studied. These volumes were quite small in order to give a more physiologic picture of the blood-tissue exchange mechanism. Therefore, the use of larger volumes in this type of work cannot be considered valid unless they are shown to have no intrinsic effect on clearance. The range of clearance from specific areas of normal skin was determined. The clearance rates from any site were reporducible, and varied with a standard deviation of[plus or minus]3%. Differences in clearance between different areas of skin were noted, and in future studies controls will have to be determined for each region being investigated. In the course of determining the normal clearance values for the skin of the arms and legs, it was noted that there was no alteration in clearance with respect to the age of the subject. The constancy of clearance from symmetrical sites in normal subjects was noted, while clearance from the skin over the affected arms of hemiplegic patients was slightly but significantly diminished when compared to the corresponding site on the contralateral limb.