Concept for Tremor Compensation for a Handheld OCT-Laryngoscope

TY - CHAP

T1 - Concept for Tremor Compensation for a Handheld OCT-Laryngoscope

AU - Donner, Sabine

AU - Deutsch, Stefanie

AU - Bleeker, Sebastian

AU - Ripken, Tammo

AU - Krueger, Alexander

N1 - 5th Scientific Meeting of the Head-and-Neck-Optical-Diagnostic-Society (HNODS), Munich, GERMANY, MAY 13-14, 2013

PY - 2013

Y1 - 2013

N2 - Optical coherence tomography (OCT) is a non-invasive imaging technique which can create optical tissue sections, enabling diagnosis of vocal cord tissue. To take full advantage from the non-contact imaging technique, OCT was adapted to an indirect laryngoscope to work on awake patients. Using OCT in a handheld diagnostic device the challenges of rapid working distance adjustment and tracking of axial motion arise. The optical focus of the endoscopic sample arm and the reference-arm length can be adjusted in a range of 40 mm to 90 mm. Automatic working distance adjustment is based on image analysis of OCT B-scans which identifies off depth images as well as position errors. The movable focal plane and reference plane are used to adjust working distance to match the sample depth and stabilise the sample in the desired axial position of the OCT scans. The autofocus adjusts the working distance within maximum 2.7 seconds for the maximum initial displacement of 40 mm. The amplitude of hand tremor during 60 s handheld scanning was reduced to 50 % and it was shown that the image stabilisation keeps the position error below 0.5 mm. Fast automatic working distance adjustment is crucial to minimise the duration of the diagnostic procedure. The image stabilisation compensates relative axial movements during handheld scanning.

AB - Optical coherence tomography (OCT) is a non-invasive imaging technique which can create optical tissue sections, enabling diagnosis of vocal cord tissue. To take full advantage from the non-contact imaging technique, OCT was adapted to an indirect laryngoscope to work on awake patients. Using OCT in a handheld diagnostic device the challenges of rapid working distance adjustment and tracking of axial motion arise. The optical focus of the endoscopic sample arm and the reference-arm length can be adjusted in a range of 40 mm to 90 mm. Automatic working distance adjustment is based on image analysis of OCT B-scans which identifies off depth images as well as position errors. The movable focal plane and reference plane are used to adjust working distance to match the sample depth and stabilise the sample in the desired axial position of the OCT scans. The autofocus adjusts the working distance within maximum 2.7 seconds for the maximum initial displacement of 40 mm. The amplitude of hand tremor during 60 s handheld scanning was reduced to 50 % and it was shown that the image stabilisation keeps the position error below 0.5 mm. Fast automatic working distance adjustment is crucial to minimise the duration of the diagnostic procedure. The image stabilisation compensates relative axial movements during handheld scanning.

KW - endoscopic optical coherence tomography

KW - laryngoscopy

KW - motion tracking

KW - autofocus

U2 - 10.1117/12.2032388

DO - 10.1117/12.2032388

M3 - SCORING: Contribution to collected editions/anthologies

SN - 978-0-8194-9813-7

VL - 8805

T3 - Proceedings of SPIE

BT - HEAD AND NECK OPTICAL DIAGNOSTICS

A2 - Betz, C

A2 - Wong, BJF

PB - SPIE-INT SOC OPTICAL ENGINEERING

CY - 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA

ER -