Use of light reflection rheography for diagnosis of axillary or subclavian venous thrombosis

Noninvasive diagnosis of axillary and subclavian venous thrombosis or documentation of the post-thrombotic syndrome using modalities currently in use is not definitive. Light reflection rheography, which is a reflection of venous pressure changes in the extremity as recorded from the subdermal capillary plexus, was used to correctly diagnose axillary or subclavian venous thrombosis in 11 patients. A positive study was confirmed by phlebography in each instance. There were no instances of false-positive results. The methodology is simple, involving testing of the venous outflow from the upper extremity in response to exercise, application of venous congesting pressure, and measurement of the rate of venous outflow when the congesting pressure is released. Normal respiratory variations of an open venous system are also assessed by this noninvasive modality. The tracing obtained is easy to interpret and provides objective evidence of proximal venous occlusion. The test is not operator-dependent and the instrumentation is relatively inexpensive. We believe that light reflection rheography may be an exciting development in the noninvasive diagnosis of axillary or subclavian venous compromise and merits further trials.