Breastfeeding plays a crucial role in public health, but relatively few imaging and sensing technologies are employed to study human lactation physiology. As a consequence, many breastfeeding problems are not well understood. We hypothesize that diffuse optical spectroscopic
imaging (DOSI) can potentially reveal important physiological parameters that help to define milk synthesis and secretion: glandular tissue content, hemodynamics and milk ejection. The aim of this study is to investigate the sensitivity of DOSI to these physiological parameters in (i) a case study (1 subject) on mammary involution of the lactating breast to its pre-pregnant state and (ii) a pilot study during milk extraction with a breast pump (4 lactating subjects, 5 non-lactating subjects). For the case study, the measured changes in the DOSI parameters (water, lipid, hemoglobin concentration) were consistent with the gradual replacement of fibro-glandular tissue by adipose tissue and vascular regression during mammary involution. For the pilot study, the measured changes in the DOSI parameters correlated with the extracted milk volume and occurrence of the milk ejection reflex. In conclusion, DOSI is sensitive to human lactation physiology, which can potentially aid to obtaining an in-depth understanding on the origin and treatment of breastfeeding problems.
Relatively few imaging and sensing technologies are employed to study human lactation physiology. In particular, human mammary development during pregnancy as well as mammary involution after lactation have been poorly described, despite their importance for breast cancer diagnosis and treatment during these phases. Our case study shows the potential of diffuse optical spectroscopic imaging (DOSI) to uniquely study the spatiotemporal changes in mammary tissue composition during the involution of the lactating breast toward its pre-pregnant state. At nine time intervals over a period of eight months after the cessation of breastfeeding, we reconstructed 2-D maps of mammary water content, lipid content, total hemoglobin (THb) concentration, oxygen saturation (StO2), and tissue optical scattering. Mammary lipid content in the nonareolar region showed a significant relative increase of 59%, whereas water content and THb concentration showed a significant relative decrease of 50% and 48%, respectively. Significant changes were also found in StO2 and tissue optical scattering. Our findings are consistent with the gradual replacement of fibroglandular tissue by adipose tissue and vascular regression during mammary involution. Moreover, our data provide unique insight into the dynamics of breast tissue composition and demonstrate the effectiveness of DOSI as a technique to study human lactation physiology.
Several studies have demonstrated that hormone-blocking therapies are more effective at reducing breast cancer risk in women who exhibit >10% reduction in breast density compared to women who had little or no density change, suggesting that breast density is a predictor of tamoxifen effectiveness. The goal of this prospective study was to assess whether diffuse optical spectroscopic imaging (DOSI) can measure the changes in breast composition under adjuvant tamoxifen treatment for breast cancer.
The primary aim was to determine whether the change in the DOSI measurement of water correlates with the change in the MRI-derived quantitative measurement of breast density after 18 months of treatment in the contralateral normal breast of subjects receiving tamoxifen. Pre-menopausal subjects receiving tamoxifen (N=11 total, N=9 analyzable) and controls (N=18 total, N=15 analyzable) were enrolled and measured with co-registered DOSI and non-contrast MRI before, and 6, 12 and 18 months after beginning tamoxifen. Across all subjects, baseline MRI fibroglandular density correlated strongly with DOSI water (r=0.86, p<0.001), moderately with lipid (r=-0.63, p=0.001), and weakly with oxyhemoglobin (r=0.55, p=0.005) and deoxyhemoglobin (r=0.42, p=0.040) concentrations. Generalized estimating equation analysis revealed significant longitudinal differences between treated subjects and controls in the percentage change of MRI fibroglandular density (at 6 and 12 mo. timepoints), DOSI water (12 and 18 mo.), DOSI lipid (6, 12 and 18 mo.) Overall the data suggest that DOSI is sensitive to tamoxifen-induced changes in the human breast, and should be investigated further as a low-cost and low-risk means to predict response to tamoxifen treatment.
Young patients with dense breasts have a relatively low-positive biopsy rate for breast cancer (∼1 in 7). South Korean women have higher breast density than Westerners. We investigated the benefit of using a functional and metabolic imaging technique, diffuse optical spectroscopic imaging (DOSI), to help the standard of care imaging tools to distinguish benign from malignant lesions in premenopausal Korean women. DOSI uses near-infrared light to measure breast tissue composition by quantifying tissue concentrations of water (ctH2O), bulk lipid (ctLipid), deoxygenated (ctHHb), and oxygenated (ctHbO2) hemoglobin. DOSI spectral signatures specific to abnormal tissue and absent in healthy tissue were also used to form a malignancy index. This study included 19 premenopausal subjects (average age 41±9), corresponding to 11 benign and 10 malignant lesions. Elevated lesion to normal ratio of ctH2O, ctHHb, ctHbO2, total hemoglobin (THb=ctHHb+ctHbO2), and tissue optical index (ctHHb×ctH2O/ctLipid) were observed in the malignant lesions compared to the benign lesions (p<0.02). THb and malignancy index were the two best single predictors of malignancy, with >90% sensitivity and specificity. Malignant lesions showed significantly higher metabolism and perfusion than benign lesions. DOSI spectral features showed high discriminatory power for distinguishing malignant and benign lesions in dense breasts of the Korean population.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.