Search PubMed⌕ Search

Biomedical subjects

T Wells

Publications and source records attributed to T Wells.

70 records · Page 4Linked to original sources
PubMed1986

CT body stereotaxis: an aid for CT-guided biopsies.

A new body stereotaxic system used to facilitate CT-guided biopsies is described. By scanning through a triangle placed on the patient's skin, the method defines an entry point for the biopsy. An articulating arm is then used to aim the needle at the entry point and hold the needle at the correct angle. The arm can be angled so that complex approaches from one scan plane to another can be made in order to take biopsies of lesions beneath the diaphragm. Using the system, 23 of 25 lesions were hit on the first needle manipulation; two manipulations were needed for each of the other two lesions. In comparison with previous experience, procedure time was decreased and the numbers of needle manipulations and localization scans were decreased 75% and 90%, respectively.

Biopsy, Needle↗
PubMed1985

CT body stereotaxic instrument for percutaneous biopsy and other interventive procedures: phantom studies.

This article describes a new body stereotaxic system that defines a fiducial point by means of a skin localization device placed directly on the patient. The system uses a rectilinear stereotaxic frame to guide the needles along the calculated path. A method for calculating paths that require angulations from one scan slice to another is described, as well. The system was tested in a foam phantom and shown to be intrinsically accurate in vitro to within 2 mm in both the x and y axis.

Biopsy, Needle↗
PubMedDate not supplied

Proteoglycan metabolism of equine articular chondrocytes cultured in alginate beads.

Equine chondrocytes were cultured in vitro for 30 days in ionically gelled alginate beads. The alginate polymerises into a stable gel in the presence of divalent cations (calcium), and rapid depolymerisation in the presence of a calcium chelator releases the viable chondrocytes. The chondrocytes maintained a spherical appearance for 30 days in culture, in marked contrast to monolayer cultures, which develop a dedifferentiated fibroblastic morphology. The major proteoglycan molecule produced by the encapsulated chondrocytes was aggrecan, of similar hydrodynamic size to aggrecan molecules present in the matrix of the articular cartilage from which the cells were harvested. Link protein, keratan sulphate and chondroitin sulphate were also synthesised by the chondrocytes, as demonstrated by immunohistochemistry. The proteoglycan secreted by the chondrocytes consisted of at least two pools, one remaining adjacent to the cell and forming a dense, cell-associated matrix, and another migrating more peripherally into the intercellular compartment. Newly synthesised proteoglycans extracted from the pericellular matrix and the intercellular matrix were similar in hydrodynamic size and aggregated in the presence of exogenous hyaluronan.

Alginates↗