Adaptable near-infrared spectroscopy fiber array for improved coupling to different breast sizes during clinical MRI.
OBJECTIVE
Near-infrared spectroscopy (NIRS) of breast can provide functional information on the vascular and structural compartments of tissues in regions identified during simultaneous magnetic resonance imaging (MRI). NIRS can be acquired during dynamic contrast-enhanced MRI (DCE-MRI) to accomplish image-guided spectroscopy of the enhancing regions, potentially increasing the diagnostic specificity of the examination and reducing the number of biopsies performed as a result of inconclusive MRI breast imaging studies.


METHODS
We combine synergistic attributes of concurrent DCE-MRI and NIRS with a new design of the clinical NIRS breast interface that couples to a standard MR breast coil and allows imaging of variable breast sizes. Spectral information from healthy volunteers and cancer patients is recovered, providing molecular information in regions defined by the segmented MR image volume.


RESULTS
The new coupling system significantly improves examination utility by allowing improved coupling of the NIR fibers to breasts of all cup sizes and lesion locations. This improvement is demonstrated over a range of breast sizes (cup size A through D) and normal tissue heterogeneity using a group of eight healthy volunteers and two cancer patients. Lesions located in the axillary region and medial-posterior breast are now accessible to NIRS optodes. Reconstructed images were found to have biologically plausible hemoglobin content, oxygen saturation, and water and lipid fractions.


CONCLUSIONS
In summary, a new NIRS/MRI breast interface was developed to accommodate the variation in breast sizes and lesion locations that can be expected in clinical practice. DCE-MRI-guided NIRS quantifies total hemoglobin, oxygenation, and scattering in MR-enhancing regions, increasing the diagnostic information acquired from MR examinations.
Thayer School of Engineering, Dartmouth College, 14 Engineering Dr., Hanover, NH 03755. Electronic address: mikem@dartmouth.edu.
Michael A
MA
Mastanduno
Thayer School of Engineering, Dartmouth College, 14 Engineering Dr., Hanover, NH 03755.
Fadi
F
El-Ghussein
Thayer School of Engineering, Dartmouth College, 14 Engineering Dr., Hanover, NH 03755.
Shudong
S
Jiang
Department of Diagnostic Radiology, Dartmouth Medical School, Lebanon, NH.
Roberta
R
Diflorio-Alexander
Department of Radiology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shannxi, China.
Xu
X
Junqing
Department of Radiology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shannxi, China.
Yin
Y
Hong
Thayer School of Engineering, Dartmouth College, 14 Engineering Dr., Hanover, NH 03755.
Brian W
BW
Pogue
Thayer School of Engineering, Dartmouth College, 14 Engineering Dr., Hanover, NH 03755; Department of Diagnostic Radiology, Dartmouth Medical School, Lebanon, NH.
Keith D
KD
Paulsen
D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000378:metabolism*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D005336:Fiber Optic Technology / Q000295:instrumentation*; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D009929:Organ Size; D010100:Oxygen / Q000378:metabolism*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation*
D014408:Biomarkers, Tumor; D006454:Hemoglobins; D010100:Oxygen
Biomedical optics; magnetic resonance imaging; spectroscopy; tomography