Motion-compensated hand-held common-path Fourier-domain optical coherence tomography probe for image-guided intervention

Abstract

A motion-compensated, hand-held, common-path, Fourier-domain optical coherence tomography imaging probe has been developed for image-guided intervention during microsurgery. A hand-held prototype instrument was achieved by integrating an imaging fiber probe inside a stainless steel needle and attached to the ceramic shaft of a piezoelectric motor housed in an aluminum handle. The fiber probe obtains A-scan images. The distance information was extracted from the A-scans to track the sample surface distance and a fixed distance was maintained by a feedback motor control which effectively compensated hand tremor and target movements in the axial direction. Real-time data acquisition, processing, motion compensation, and image visualization and saving were implemented on a custom CPU-GPU hybrid architecture. We performed 10× zero padding to the raw spectrum to obtain 0.16 µm position accuracy with a compensation rate of 460 Hz. The root-mean-square error of hand-held distance variation from target position was measured to be 2.93 µm. We used a cross-correlation maximization-based shift correction algorithm for topology correction. To validate the system, we performed free-hand OCT M-scan imaging using various samples.

Fibre-coupled multiphoton microscope with adaptive motion compensation

“…Our motion compensation system follows the approach described in references [11,12] but with several differences. First, the microscope objective in our system is relatively massive compared to the graded-index lenses used in the fibre-based systems described in [11,12].…”

“…This system could compensate motion with an amplitude of up to 60 μm at average speeds of up to 72 μm.s 1 and maintained the focus to within 5 μm. In subsequent work by the same group, a similar approach was used to demonstrate axial motion compensation in a hand-held SDOCT imaging system that achieved an RMS surface error of 2.93 μm when the probe was hand-held [12]. An alternative system used an off-axis optical focus sensor with a multiphoton imaging system [13] in order to reduce motion in the spina lamina I neurons of anaesthetized male Wistar rats to less than the axial resolution of the imaging system.…”

Accurate real-time depth control for CP-SSOCT distal sensor based handheld microsurgery tools

“…Our research group has established a potential role for a real-time OCT intraoperative guidance system with fast computational speed using a graphic processing unit (GPU) that is forward viewing and incorporated into the actual handheld tools [24][25][26][27][28][29][30][31][32][33][34][35]. Unlike typical OCT imaging, this application uses OCT as a distal sensor and its potential effectiveness for ocular microsurgery has been demonstrated [29][30][31][32][33][34][35]. The motion compensation that is based on the feedback from the OCT distal sensor effectively suppresses undesired axial motion; as a result, the frequency region related to hand tremor is significantly decreased [34].…”

Miniature real-time intraoperative forward-imaging optical coherence tomography probe

“…It is capable of being introduced into a microsurgical biopsy needle to assist in obtaining optimal specimens. However, this design is unable to provide 2-dimensional information unless the entire needle moves to produce a scan [24,25]. A 25-gauge (0.51 mm) common-path OCT probe has been developed [24,25].…”

“…However, this design is unable to provide 2-dimensional information unless the entire needle moves to produce a scan [24,25]. A 25-gauge (0.51 mm) common-path OCT probe has been developed [24,25]. However, the probe tip must be positioned within 1.6 mm of a delicate tissue, such as retina, with scanning of the entire probe without touching the easily damaged tissue to produce 33 µm lateral resolution images at a sampling rate of 460 A-scans per second [25].…”