Abstract
CONTEXT: Facial plethora is a clinical sign described since ancient times for a variety of diseases. In the 19th century, it was linked to increased blood volume or flow, but this has never been proven. Facial plethora is also one of the earliest described clinical features of Cushing's syndrome (CS). OBJECTIVE: This study aimed to quantify facial plethora changes in CS as an early assessment of cure after surgery using noninvasive near-infrared multispectral imaging (MSI). DESIGN: The longitudinal cohort study was initiated in August 2012 and completed in August 2014. SETTING: Clinical research hospital, National Institutes of Health. PATIENTS: Thirty-four of the 38 patients who received surgical treatment for CS under protocol 97CH0076 during this period were included. INTERVENTION(S): MSI was performed on the right cheek of patients before surgery and 4.9 ± 3.1 days afterward. MAIN OUTCOME MEASURE(S): Average blood volume fraction as measured by MSI and serum cortisol. RESULTS: All but four of the 28 patients (86%) who were assessed as cured by postoperative plasma cortisol measurements of < 3 μg/dL showed a decrease in blood volume fraction (17.7 ± 0.03 vs 15.8 ± 0.03%; P = .0019), whereas an increase was seen in patients with persistent CS (18.5 ± 0.03 vs 21.4 ± 0.04%; P = .0017). Change in blood volume fraction before and after surgery was correlated with postoperative cortisol (rs = 0.58; P = .0003). CONCLUSIONS: Clinical data obtained from 34 patients indicate that a decrease in facial plethora after surgery, as evidenced by a decrease in blood volume fraction, is correlated with CS outcome. This novel technology for the first time identified a physiological mechanism associated with an ancient clinical sign. Furthermore, as a proof of principle, MSI is a promising early marker of cure in patients with CS that complements biochemical and clinical data.