The validation of the Depth Measurement Videomicroscope (DMV) as a noninvasive tool for the assessment of capillary vascular malformations.

The assessment of capillary vascular malformation (CM) morphology can be performed using videomicroscopy. Previously only the type of capillary pattern could be demonstrated. The Depth Measurement Videomicroscope (DMV) allows both depth and diameter of CM vessels to be measured. The aim of this study was to examine how videomicroscope recordings correlated with biopsy recordings and to investigate pressure-related changes in recordings when using the device. For the first part of the study, 10 patients with CMs resting in a temperature-controlled room were assessed with the DMV. Following this a 3mm punch biopsy of the area was taken. The depth and diameter measurements taken with the DMV were compared to those obtained histologically. For the second part of the study, pressure measurement was used to determine the amount of pressure required on the tip of the DMV to alter the results obtained. Five recordings were taken on the forearm of one volunteer. When the DMV and biopsy measurements are compared using a Bland and Altman Test to determine their relationship there is a close agreement with the diameter measurements and a correction factor of -0.100mm for the depth measurements. The pressure required to alter the skin microcirculation when placing the DMV on the skin surface was found to be 62mmHg. This corresponds closely with other studies of pressure effects on the skin microcirculation and exceeds the pressure used when using the DMV. The DMV thus provides a useful tool for assessing CM capillary structure.