The poor man's capillary microscope. A novel technique for the assessment of capillary morphology

To evaluate a new method for rapid and efficient assessment of capillary morphology.

Nailfold capillary morphology in 18 patients with Raynaud's phenomenon was investigated with a new bedside test, based on a modified dermatoscope using a novel gel-immersion technique. These findings were compared with those obtained by standard capillary microscopy.

With the standard microscope, six patients had dilated capillaries, six had mega-capillaries, seven had avascular fields, eight had ramified capillaries, six had contorted capillaries, and seven patients showed micro-haemorrhages, respectively. The dermatoscope identified exactly the same patients to have the same capillary abnormalities. One hundred and thirty six fingers were available for pairwise comparison: The kappa statistic was 0.93 for dilated capillaries, 0.97 for mega-capillaries, 0.93 for avascular areas, 0.78 for ramified capillaries, 0.81 for contorted capillaries, and 0.94 for micro-haemorrhages, respectively. The average examination time was 18 (range 8-30) minutes with the standard microscope and 4 (3-8) minutes with the dermatoscope.

A new diagnostic tool for rapid and efficient examination of nailfold capillaries is described for circumstances when a standard microscope is not available. This study shows that the hand held device can be used in clinical routine with sufficient diagnostic efficacy and little expenditure, both timewise and financially.