Even the best guess is not as good as a measurement

Abstract

Eric Temple Bell's “obvious is the most dangerous word” is as applicable to medicine as it is to mathematics. Sometimes what appears to be obvious to experts in a specific field of medicine is far from obvious to clinicians in other specialties. Providing solid evidence for the “obvious” not only serves an educational role but also improves the standard of care. For example, it is obvious to a venous specialist that venous reflux time should be measured using duplex ultrasound with spectral Doppler tracing. The current definition of reflux is based on the critical value of its duration. A millisecond difference in duration can result in one image interpreted as “normal” and another as having an incompetent valve. However, this definition of reflux is not so obvious for specialists in other areas of medicine. Why not just use much cheaper ultrasound equipment, even if it lacks measurement ability? Can't one watch the color Doppler or listen to a hand-held Doppler with acoustic output and guess if the time of the venous flow reversal exceeds its critical value? Some health care providers may argue that their estimates are as good as a spectral Doppler measurement. This is a dangerous assumption for there are multiple examples when such guesses are used to justify unnecessary procedures. Comparison of hand-held acoustic Doppler with point-of-care portable color Doppler ultrasound in the assessment of venous reflux diseaseJournal of Vascular Surgery: Venous and Lymphatic DisordersVol. 8Issue 5PreviewDiagnostic-quality portable color Doppler ultrasound (PCD) offers convenient point-of-care venous reflux disease (VRD) diagnosis. Philips Lumify (Philips N.V., Best, The Netherlands), a high-fidelity broadband linear array transducer (4-12 MHz frequency), connects through a web-enabled smartphone or tablet to cloud software and offers B-mode and color Doppler imaging without pulsed wave Doppler capability. The aims of the study were to compare hand-held acoustic Doppler (HHD) vs PCD diagnostic performance using conventional duplex ultrasound (DUP) as the “gold standard” for VRD assessment, to assess effects of body mass index (BMI) and disease severity on diagnostic performance of HHD and PCD, and to determine whether PCD offers any diagnostic improvement over HHD in VRD assessment. Full-Text PDF