Non-invasive optical and laboratory hematologic biomarkers correlate in patients with sickle cell disease.

The goal of this study is to identify non-invasive optical hemodynamic biomarkers that can index laboratory hematology measurements in sickle cell disease (SCD). We acquired frequency-domain NIRS (FD-NIRS) and diffuse correlation spectroscopy (DCS) data from the forearms and foreheads of 17 participants in a randomized, double-blind, placebo-controlled trial evaluating effects of isoquercetin (IQ) on thromboinflammation in SCD. We observed multiple, significant correlations between optical and hematology biomarkers including cerebral tissue oxygen saturation (StO) and hematocrit (HCT); oxyhemoglobin ([OHb]) recovery rate and intercellular adhesion molecule 1 (ICAM-1); and blood flow index (BFI) reperfusion rate and coagulation index (CI).

The HEALthy Brain and Child Development Study (HBCD): NIH collaboration to understand the impacts of prenatal and early life experiences on brain development.

The human brain undergoes rapid development during the first years of life. Beginning in utero, a wide array of biological, social, and environmental factors can have lasting impacts on brain structure and function. To understand how prenatal and early life experiences alter neurodevelopmental trajectories and shape health outcomes, several NIH Institutes, Centers, and Offices collaborated to support and launch the HEALthy Brain and Child Development (HBCD) Study.

AAPM Task Group Report 311: Guidance for performance evaluation of fluorescence-guided surgery systems.

The last decade has seen a large growth in fluorescence-guided surgery (FGS) imaging and interventions. With the increasing number of clinical specialties implementing FGS, the range of systems with radically different physical designs, image processing approaches, and performance requirements is expanding. This variety of systems makes it nearly impossible to specify uniform performance goals, yet at the same time, utilization of different devices in new clinical procedures and trials indicates some need for common knowledge bases and a quality assessment paradigm to ensure that effective translation and use occurs.

Diffuse optical spectroscopic method for tissue and body composition assessment.

Significance: Growing levels of obesity and metabolic syndrome have driven demand for more advanced forms of body composition assessment. While various techniques exist to measure body composition, devices are typically expensive and not portable, involve radiation [in the case of dual-energy x-ray absorptiometry (DXA)], and are limited to analysis of adiposity while metabolic information from blood supply and oxygenation are not considered.

Aim: We evaluate whether diffuse optical spectroscopic imaging (DOSI) can be used to predict site-specific adiposity and percent fat (whole body) while simultaneously providing information about local tissue hemoglobin levels and oxygenation.

Multimodal analyses of vitiligo skin identify tissue characteristics of stable disease.

Vitiligo is an autoimmune skin disease characterized by the destruction of melanocytes by autoreactive CD8+ T cells. Melanocyte destruction in active vitiligo is mediated by CD8+ T cells, but the persistence of white patches in stable disease is poorly understood. The interaction between immune cells, melanocytes, and keratinocytes in situ in human skin has been difficult to study due to the lack of proper tools.

Quantitative measurement of optical properties and Hb concentration in a rodent model of inflammatory Meibomian gland dysfunction using spatial frequency domain imaging.

Herein, to investigate a new diagnostic method for Meibomian gland dysfunction (MGD) induced by eyelid inflammation, optical properties and deoxy-hemoglobin (Hb) concentrations in rodent eyelid tissues, including Meibomian glands(MGs), were measured using spatial frequency domain imaging (SFDI). Complete Freund's adjuvant solutions were injected into the eyelid margins of Sprague-Dawley rats to induce MGD. After three weeks, the optical properties and Hb of the MG and non-MG regions of the eyelids were measured using an SFDI system.

Characterizing tourniquet induced hemodynamics during total knee arthroplasty using diffuse optical spectroscopy.

Tourniquet use creates a reduced blood surgical field during total knee arthroplasty (TKA), however, prolonged ischemia may cause postoperative tourniquet complications. To understand the effects of tourniquet-induced ischemia, we performed a prospective observational study using quantitative broadband diffuse optical spectroscopy (DOS) to measure tissue hemodynamics and water and lipid concentrations before, during, and after tourniquet placement in subjects undergoing TKA. Data was collected for 6 months and, of the total subjects analyzed (n = 24), 22 were primary TKAs and 2 were revision TKA cases.

High-speed quantitative optical imaging of absolute metabolism in the rat cortex.

Quantitative measures of blood flow and metabolism are essential for improved assessment of brain health and response to ischemic injury. We demonstrate a multimodal technique for measuring the cerebral metabolic rate of oxygen ( ) in the rodent brain on an absolute scale ( ). We use laser speckle imaging at 809 nm and spatial frequency domain imaging at 655, 730, and 850 nm to obtain spatiotemporal maps of cerebral blood flow, tissue absorption ( ), and tissue scattering ( ).

Lipid remodeling in response to methionine stress in MDA-MBA-468 triple-negative breast cancer cells.

Methionine (Met) is an essential amino acid and critical precursor to the cellular methyl donor S-adenosylmethionine. Unlike nontransformed cells, cancer cells have a unique metabolic requirement for Met and are unable to proliferate in growth media where Met is replaced with its metabolic precursor, homocysteine. This metabolic vulnerability is common among cancer cells regardless of tissue origin and is known as "methionine dependence", "methionine stress sensitivity", or the Hoffman effect.

Breast cancer differential diagnosis using diffuse optical spectroscopic imaging and regression with z-score normalized data.

Significance: Current imaging paradigms for differential diagnosis of suspicious breast lesions suffer from high false positive rates that force patients to undergo unnecessary biopsies. Diffuse optical spectroscopic imaging (DOSI) noninvasively probes functional hemodynamic and compositional parameters in deep tissue and has been shown to be sensitive to contrast between normal and malignant tissues.

Aim: DOSI methods are under investigation as an adjunct to mammography and ultrasound that could reduce false positive rates and unnecessary biopsies, particularly in radiographically dense breasts.

Kinetic Analysis of Lipid Metabolism in Breast Cancer Cells via Nonlinear Optical Microscopy.

Investigating the behavior of breast cancer cells via reaction kinetics may help unravel the mechanisms that underlie metabolic changes in tumors. However, obtaining human in vivo kinetic data is challenging because of difficulties associated with measuring these parameters. Nondestructive methods of measuring lipid content in live cells provide a novel approach to quantitatively model lipid synthesis and consumption.

Non-invasive optical biopsy by multiphoton microscopy identifies the live morphology of common melanocytic nevi.

Multiphoton microscopy (MPM) is a promising non-invasive imaging tool for discriminating benign nevi from melanoma. In this study, we establish a MPM morphologic catalogue of common nevi, information that will be critical in devising strategies to distinguish them from nevi that are evolving to melanoma that may present with more subtle signs of malignancy. Thirty common melanocytic nevi were imaged in vivo using MPM.

Diffuse optical spectroscopic imaging reveals distinct early breast tumor hemodynamic responses to metronomic and maximum tolerated dose regimens.

Background: Breast cancer patients with early-stage disease are increasingly administered neoadjuvant chemotherapy (NAC) to downstage their tumors prior to surgery. In this setting, approximately 31% of patients fail to respond to therapy. This demonstrates the need for techniques capable of providing personalized feedback about treatment response at the earliest stages of therapy to identify patients likely to benefit from changing treatment.

Dissociation of Cerebral Blood Flow and Femoral Artery Blood Pressure Pulsatility After Cardiac Arrest and Resuscitation in a Rodent Model: Implications for Neurological Recovery.

Background Impaired neurological function affects 85% to 90% of cardiac arrest (CA) survivors. Pulsatile blood flow may play an important role in neurological recovery after CA. Cerebral blood flow (CBF) pulsatility immediately, during, and after CA and resuscitation has not been investigated.

Monocular 3D Probe Tracking for Generating Sub-Surface Optical Property Maps From Diffuse Optical Spectroscopic Imaging.

Objective: Diffuse optical spectroscopic imaging (DOSI) is a promising biophotonic technology for clinical tissue assessment, but is currently hampered by difficult wide area assessment. A co-integrative optical imaging system is proposed for dense sub-surface optical property spatial assessment.

Methods: The proposed system fuses a co-aligned set of camera frames and diffuse optical spectroscopy measurements to generate spatial sub-surface optical property maps.

Special Section Guest Editorial: Special Section on Spatial Frequency Domain Imaging.

This guest editorial introduces the Special Section on Spatial Frequency Domain Imaging.

Diffuse optical spectroscopic imaging for the investigation of human lactation physiology: a case study on mammary involution.

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.

Real-time, wide-field, and quantitative oxygenation imaging using spatiotemporal modulation of light.

Quantitative diffuse optical imaging has the potential to provide valuable functional information about tissue status, such as oxygen saturation or blood content to healthcare practitioners in real time. However, significant technical challenges have so far prevented such tools from being deployed in the clinic. Toward achieving this goal, prior research introduced methods based on spatial frequency domain imaging (SFDI) that allow real-time (within milliseconds) wide-field imaging of optical properties but at a single wavelength.

Special Section Guest Editorial: Translational Biophotonics.

This guest editorial introduces the special section on Translational Biophotonics.

In vivo multiphoton microscopy of melasma.

Melasma is a skin disorder characterized by hyperpigmented patches due to increased melanin production and deposition. In this pilot study, we evaluate the potential of multiphoton microscopy (MPM) to characterize non-invasively the melanin content, location, and distribution in melasma and assess the elastosis severity. We employed a clinical MPM tomograph to image in vivo morphological features in melasma lesions and adjacent normal skin in 12 patients.

Tissue oxygen saturation predicts response to breast cancer neoadjuvant chemotherapy within 10 days of treatment.

Ideally, neoadjuvant chemotherapy (NAC) assessment should predict pathologic complete response (pCR), a surrogate clinical endpoint for 5-year survival, as early as possible during typical 3- to 6-month breast cancer treatments. We introduce and demonstrate an approach for predicting pCR within 10 days of initiating NAC. The method uses a bedside diffuse optical spectroscopic imaging (DOSI) technology and logistic regression modeling.