Apparatus and method for measuring an optical break-through in a tissue

Abstract

The invention relates to a device for measuring an optical penetration that is triggered in a tissue underneath the tissue surface by means of therapeutic laser radiation which a laser-surgical device concentrates in a treatment focus located in said tissue. The inventive device is provided with a detection beam path comprising a lens system which couples radiation emanating from the tissue underneath the tissue surface into the detection beam path. A detector device generating a detection signal which indicates the spatial dimension and/or position of the optical penetration in the tissue is arranged downstream of the detection beam path.

1 . (canceled) 
     
     
         2 . A method of eye surgery, comprising:
 emitting illumination laser radiation toward a tissue of an eye to a focus and shifting the focus to different positions by variably deflecting the illumination laser radiation thereby inducing a response from the tissue;   producing tissue-specific signals related to the response from the tissue;   assigning the tissue-specific signals to points of measurement in the tissue;   wherein each of the points of measurement is assigned to one of the positions of the focus;   detecting a position of at least one structure on a basis of the points of measurement, the at least one structure being selected from a group consisting of: a boundary layer of the tissue and an inclusion within the tissue;   defining a cut within the tissue on a basis of the points of measurement or the detected structure; and   generating the cut within the tissue by irradiating treating laser radiation to the tissue, wherein the treating laser radiation has laser pulses of a pulse width between 1 fs and 100 ps.   
     
     
         3 . The method as claimed in  claim 2 , further comprising defining the cut by determining or selecting target points to which treating laser radiation is to be focused. 
     
     
         4 . The method as claimed in  claim 2 , further comprising focusing the treating laser radiation to a focal point within the tissue and shifting the position of the focal point along a path comprising the cut. 
     
     
         5 . The method as claimed in  claim 3 , further comprising shifting the position of the focal point of the treating laser radiation along a path comprising the target points. 
     
     
         6 . The method as claimed in  claim 2 , further comprising utilizing a focusing unit to focus the treating laser radiation, and using the focusing unit also to focus the illumination laser radiation. 
     
     
         7 . The method as claimed in  claim 2 , further comprising utilizing a deflecting unit to shift the focal point of the treating laser radiation within the tissue, and using the deflecting unit also to shift the focus of the illumination laser radiation. 
     
     
         8 . The method as claimed in  claim 2 , further comprising providing the illumination laser radiation and also the treating laser radiation from one single radiation source operated in different mode. 
     
     
         9 . The method as claimed in  claim 2 , further comprising selecting the tissue from a group consisting of: a lens, a vitreous body, a cornea and a sclera of an eye. 
     
     
         10 . The method as claimed in  claim 2 , further comprising using a super luminescence diode for emitting the illumination laser. 
     
     
         11 . The method as claimed in  claim 2 , further comprising emitting the treating laser radiation in laser pulses of a wavelength in the infra-red or visible spectral range for which the tissue is transparent, wherein the pulses trigger a non-linear optical process in the tissue. 
     
     
         12 . The method as claimed in  claim 11 , further comprising emitting the treating laser radiation in a wavelength of between 400 nm and 1,900 nm. 
     
     
         13 . The method as claimed in  claim 2 , wherein the tissue-specific signals are OCT signals. 
     
     
         14 . The method as claimed in  claim 2 , further comprising irradiating the illumination laser radiation along a first optical axis and detecting the tissue-specific signals along a second optical axis which is oblique to the first optical axis to determine the points of measurement according to a slit-lamp principle. 
     
     
         15 . A device for measuring or treating a transparent or semi-transparent tissue of an eye, the device comprising:
 a source of laser radiation adapted to emit illumination laser radiation;   a focusing unit focusing the illumination laser radiation toward the tissue to a focus thereby inducing a response from the tissue;   a deflecting unit adapted to shift a position of the focus relative to the eye;   a detector unit producing tissue-specific signals related to the response from the tissue; a source of treating laser radiation emitting treating laser radiation as laser pulses of a pulse width between 1 fs and 100 ps; and   a control unit receiving the tissue-specific signals from the detector unit and controlling the deflecting unit and/or the focusing unit such that the focus of the illumination laser radiation is positioned at different positions;   wherein said control unit assigns said tissue-specific signals to points of measurement whose location in the tissue is defined by the respective position of the focus at which the tissue-specific signal was obtained;   wherein said control unit detects a position of at least one structure on a basis of the points of measurement, the at least one structure being selected from a group consisting of: a boundary layer of the tissue and an inclusion within the tissue; and   wherein said control unit defines, on a basis of the points of measurement or the detected structure a cut to be generated within the tissue and controls the source of treating laser radiation to apply the treating laser radiation to the tissue.   
     
     
         16 . The device as claimed in  claim 15 , wherein the control unit defines the cut by determining or selecting target points to which the treating laser radiation is to be focused. 
     
     
         17 . The device as claimed in  claim 15 , wherein the focusing unit also focuses the treating laser radiation to a focal point. 
     
     
         18 . The device as claimed in  claim 15 , wherein the deflecting unit also shifts the position of the focal point of the treating laser radiation. 
     
     
         19 . The device as claimed in  claim 15 , wherein the source of illumination radiation is a superluminescent diode. 
     
     
         20 . The device as claimed in  claim 15 , wherein a single source of laser radiation comprises a first and a second operating mode and emits the illumination laser radiation in the first mode and the treating laser radiation in the second mode, thereby acting as the source of illumination laser radiation and as the source of treating laser radiation. 
     
     
         21 . The device as claimed in  claim 20 , wherein the source of laser radiation comprises a switchable energy reducer, which is switched to an active state in the first mode of the source of laser radiation and switched to an inactive state in the second mode of the source of laser radiation. 
     
     
         22 . The device as claimed in  claim 15 , wherein the source of illumination radiation comprises an OCT illumination radiation source and the detection unit comprises the OCT. 
     
     
         23 . The device as claimed in  claim 15 , wherein the detection unit has an optical axis which is located obliquely to an optical axis of the illumination laser radiation to determine the points of measurement according to a slit-lamp principle.