Claude Colin | PubMed Health

PubMed2003

Interferential scanning grating position sensor operating in space at 4 K.

An interferential position sensor for operation in space at a deep cryogenic temperature (4 K) is derived from a commercial sensor. The application is for the Spectral and Photometric Imaging Receiver submillimetric imaging Fourier-transform spectrometer on the Herschel space telescope. This sensor is used to control the displacement of the interferometer's moving mirrors and to sample the interferograms. This development addresses the following points: minimization of the effects of cooling critical optical parts, introduction of a fully redundant focal plane, selection of optoelectronic components efficient at 4 K, and design of a cryogenic preamplifier.

Journal Article↗

PubMed2002

Stereotactic breast biopsy with an 8-gauge, directional, vacuum-assisted probe: initial experience.

This study was prospectively conducted to assess the feasibility, safety and accuracy of an 8-G directional vacuum-assisted biopsy (DVAB) probe in the diagnostic management of nonpalpable breast lesions (NPBL). Of 170 planned procedures which were indicated for investigation of BI-RADS category-3 to category-5 lesions, 153 were performed in 138 consecutive patients. The probe was targeted by the stereotactic unit of a prone table (United States Surgical Corporation, Norwalk, Conn.; and Lorad, Danbury, Conn.). Four to 18 (mean 8) core specimens were obtained for each lesion. In case of complete removal of the lesion, a localizing clip was deployed at the biopsy site. Adequate material for histopathologic examination was obtained in all cases (100%). Four of 138 (3%) patients experienced mild hematomas. We observed 15 of 39 failures (38%) to place the localizing clips. Thirteen of 153 (8%) procedures were inconclusive and required reintervention. Following DVAB, 42 of 138 (30%) patients underwent surgery. Subject to incomplete follow-up of the entire cohort, we observed no false-positive and one false-negative diagnosis. These preliminary results suggest that DVAB using an 8-G probe are feasible, safe and accurate. In our experience, clip placement was problematic. It is probable that increasing the dimensions of DVAB will only be relevant in a limited number of clinical situations, primarily the desire to obtain complete radiologic resections of the target abnormality.

Biopsy↗