Method and system for optically evaluating proximity to the inferior alveolar nerve in situ

摘要

A low coherence interferometry probe system for evaluating proximity to a tissue layer, comprising a low coherence light source, an excitation optical fiber to bring the low coherence excitation light near the tissue layer and a collection optical fiber for capturing back-scattered light from the tissue layer. The probe system comprises an interferometry sub-system and a processor for evaluating a distance to the tissue layer. There is also provided a spectral absorption probe system for evaluating proximity to an artery, comprising a light source excitation light having a wavelength adapted for absorption by blood chromophores, an excitation optical fiber and a collection optical fiber. The probe system comprises a light detector and a processor for determining a distance to the artery using the Beer-Lambert law of light absorption with a value for surrounding tissue attenuation coefficient (μeff). A probe system combining low coherence interferometry and spectral absorption is also provided.

主权项

1. A spectral absorption probe system for determining a distance between a tissue layer including an artery and a surgical drill tip during a procedure, comprising:
a light source of the spectral absorption probe system for generating excitation light having a wavelength configured for absorption by blood chromophores; an excitation optical channel of the spectral absorption probe system to bring said excitation light near the tissue layer and the artery; a collection optical channel of the spectral absorption probe system, distinct from said excitation optical channel, for capturing diffused back-scattered light from said tissue layer and the artery, where said diffused back-scattered light is modulated by blood flow dynamics in said artery, said blood flow dynamics being a periodic change in blood volume in said artery due to a cardiac cycle; a light detector of the spectral absorption probe system operatively connected to said collection optical channel for detecting said diffused back-scattered light modulated by blood flow dynamics and for generating an oscillating signal, a frequency of said oscillating signal being related to said periodic change; and a signal processor of the spectral absorption probe system operatively connected to said light detector for determining the distance between the tissue layer including the artery and the surgical drill tip based on said back-scattered light using an amplitude of said oscillating signal and a value for surrounding tissue attenuation coefficient; wherein at least one of the excitation optical channel and the collection optical channel is included in an optical fiber and the optical fiber is integrated within a hollow core of a surgical drill bit including the surgical drill tip.