49 research outputs found
Deep tissue volume imaging of birefringence through fibre-optic needle probes for the delineation of breast tumour
Published online: 01 July 2016Identifying tumour margins during breast-conserving surgeries is a persistent challenge. We have previously developed miniature needle probes that could enable intraoperative volume imaging with optical coherence tomography. In many situations, however, scattering contrast alone is insufficient to clearly identify and delineate malignant regions. Additional polarization-sensitive measurements provide the means to assess birefringence, which is elevated in oriented collagen fibres and may offer an intrinsic biomarker to differentiate tumour from benign tissue. Here, we performed polarization-sensitive optical coherence tomography through miniature imaging needles and developed an algorithm to efficiently reconstruct images of the depth-resolved tissue birefringence free of artefacts. First ex vivo imaging of breast tumour samples revealed excellent contrast between lowly birefringent malignant regions, and stromal tissue, which is rich in oriented collagen and exhibits higher birefringence, as confirmed with co-located histology. The ability to clearly differentiate between tumour and uninvolved stroma based on intrinsic contrast could prove decisive for the intraoperative assessment of tumour margins.Martin Villiger, Dirk Lorenser, Robert A. McLaughlin, Bryden C. Quirk, Rodney W. Kirk, Brett E. Bouma and David D. Sampso
A Nationwide 2010-2012 Analysis of U.S. Health Care Utilization in Inflammatory Bowel Diseases
Cellular mechanisms in basic and clinical gastroenterology and hepatolog
Deep tissue volume imaging of birefringence through fibre-optic needle probes for the delineation of breast tumour
Identifying tumour margins during breast-conserving surgeries is a persistent challenge. We have previously developed miniature needle probes that could enable intraoperative volume imaging with optical coherence tomography. In many situations, however, scattering contrast alone is insufficient to clearly identify and delineate malignant regions. Additional polarization-sensitive measurements provide the means to assess birefringence, which is elevated in oriented collagen fibres and may offer an intrinsic biomarker to differentiate tumour from benign tissue. Here, we performed polarization-sensitive optical coherence tomography through miniature imaging needles and developed an algorithm to efficiently reconstruct images of the depth-resolved tissue birefringence free of artefacts. First ex vivo imaging of breast tumour samples revealed excellent contrast between lowly birefringent malignant regions, and stromal tissue, which is rich in oriented collagen and exhibits higher birefringence, as confirmed with co-located histology. The ability to clearly differentiate between tumour and uninvolved stroma based on intrinsic contrast could prove decisive for the intraoperative assessment of tumour margins
Polarization sensitive OCT with needle probes
We demonstrate polarization sensitive OCT using miniaturized needle probes. Employing the Mueller-formalism, we reconstruct tissue birefringence and retrieve the depolarization index of ex vivo tissue samples, providing contrast complementary to the structural intensity signal
Polarization sensitive OCT with needle probes
We demonstrate polarization sensitive OCT using miniaturized needle probes. Employing the Mueller-formalism, we reconstruct tissue birefringence and retrieve the depolarization index of ex vivo tissue samples, providing contrast complementary to the structural intensity signal
Arthropoda: Decapoda
Decopod crustaceans are classified as an order of crustaceans in the phylum Arthropoda, class Malacostraca. Because decapod crustaceans are grossly, this chapter uses the lobster as the model in most discussions, and describes important anatomic differences that occur in other decapods. The lobster\u27s body is elongated and divided into a cephalothorax and an abdomen. The hard carapace that makes up most of the cephalothorax is further divided into head and thoracic regions by various indentations on the carapace. Underlying the carapace epithelium is the “spongy” hypodermis composed of large vacuolated cells (the glycogen contents are removed during histologic processing). The gastrointestinal tract of decapods is divided into the esophagus, foregut, midgut, hindgut, anterior and posterior ceca, and digestive gland. The excretory system of a decapod crustacean is the primary means of eliminating nitrogenous wastes and is composed of several parts: a coelomosac, a labyrinth, a bladder and bladder duct, a nephridiopore, and the surrounding hemosinus