Neonatal brain resting-state functional connectivity imaging modalities

Abstract

Infancy is the most critical period in human brain development. Studies demonstrate that subtle brain abnormalities during this state of life may greatly affect the developmental processes of the newborn infants. One of the rapidly developing methods for early characterization of abnormal brain development is functional connectivity of the brain at rest. While the majority of resting-state studies have been conducted using magnetic resonance imaging (MRI), there is clear evidence that resting-state functional connectivity (rs-FC) can also be evaluated using other imaging modalities. The aim of this review is to compare the advantages and limitations of different modalities used for the mapping of infants’ brain functional connectivity at rest. In addition, we introduce photoacoustic tomography, a novel functional neuroimaging modality, as a complementary modality for functional mapping of infants’ brain.

Low Temperature-Mediated Enhancement of Photoacoustic Imaging Depth

“…Photoacoustic Imaging (PAI) is a promising functional and molecular imaging technique for a wide range of biomedical applications [1]. PAI combines the technological advances of both optical and acoustic imaging, i.e., the high intrinsic contrast of optical imaging and the spatial resolution of ultrasound imaging [2,3,49]. Every material, including bodily substances, has a specific optical absorption coefficient unique to endogenous chromospheres in cells [2,3].…”

Development of Low-Cost Fast Photoacoustic Computed Tomography: System Characterization and Phantom Study

“…Photoacoustic imaging (PAI) is a promising imaging technique that combines higher imaging contrast of optical imaging with deeper penetration of ultrasonic imaging [1][2][3]. A nanosecond pulsed laser deposits energy onto a light absorbing sample, causing a local temperature increase and subsequent thermal expansion through the thermoacoustic effect [2,[4][5][6][7][8]. This expansion causes a localized pressure increase, which propagates from the sample to be imaged, by an ultrasound transducer, similar to a traditional ultrasound detection system.…”

Photoacoustic molecular imaging using combined acupuncture and gold nanorods as a composite contrast agent

“…[1][2][3][4][5][6][7] This in vivo brain functional imaging technique has the following unique advantages: (1) it is an noninvasive imaging mode which is conducted in accordance with ethical principles; (2) animals can maintain normal physiological activity during imaging; (3) it has adequate spatial resolution (up to tens of m), temporary resolution (up to tens of ms) and limited depth of penetration (up to several mm, with intact scalp) in monitoring the brain; (4) it provides high-resolution functional information, such as hemoglobin and blood oxygenation levels relevant to describing physiology and pathology. 6,[8][9][10][11][12][13][14][15][16][17][18][19][20] PAT of small animal brain has successfully been implemented. 3,[8][9][10][11][12][13] In these studies, PAT was used for mapping the microvascular network of a mouse brain with the hemodynamic activities when the scalp and skull were intact.…”

“…8,10 Recently, several research demonstrated that the neonatal brain imaging through fontanel using photoacoustic technique is feasible. [14][15][16][17][18][19][20] Even though the skull and scalp of any small animal is thin, the penetration depth is limited. 17,20 In the situation where a limited detection depth is certain, or an endogenous contrast is not available, an exogenous contrast agent can be utilized.…”

“…[14][15][16][17][18][19][20] Even though the skull and scalp of any small animal is thin, the penetration depth is limited. 17,20 In the situation where a limited detection depth is certain, or an endogenous contrast is not available, an exogenous contrast agent can be utilized. Oral or injectable chemicals, known as exogenous contrast agents, can be used to enhance images in medical scans of the tissues or organs.…”