A needle device comprising: a hollow shaft having a first distal end portion with a bevel; an elongated insert having a second distal end portion and being movably arranged within the hollow shaft, wherein the second distal end portion of the elongated insert comprises a front surface with at least one of a beveled portion, a stepped portion and a blunt portion; a first optical fiber having a front surface, wherein the front surface is arranged at the front surface of the elongated insert; a second optical fiber with a front surface, wherein the front surface of the second fiber is arranged at the front surface of the elongated insert, wherein the front surface of the first optical fiber is arranged distally relative to the front surface of the second optical fiber; an operating means being shiftable between a first condition and a second condition; a console including a light source, a light detector and a processing unit for processing the signals provided by the light detector, wherein one of the light source and the light detector is connected with the first optical fiber and the other one of the light source and the light detector is connected with the second optical fiber; and a switch for activating optical measurements by the console; wherein the operating means is interconnected with the elongated insert and with the switch, so that when the operating means is in the first condition the second distal end portion is located within the hollow shaft and proximally to the bevel, and so that when the operating means is in the second condition the second distal end portion is located outside the hollow shaft and distally to the bevel; wherein the operating means includes a first lever and a second lever, wherein the first lever is rotatable between the first condition and the second condition, and wherein the second lever is arranged between the first lever and the elongated insert, so that a rotational movement of the first lever is converted in a translational movement of the elongated insert to shift the operating means between the first condition and the second condition; and wherein, the switch is configured to trigger the optical measurements due to a pushing of the first lever. a hollow shaft having a first distal end portion with a bevel; an elongated insert having a second distal end portion and being movably arranged within the hollow shaft, wherein the second distal end portion of the elongated insert comprises a front surface with at least one of a beveled portion, a stepped portion and a blunt portion; a first optical fiber having a front surface, wherein the front surface is arranged at the front surface of the elongated insert; a second optical fiber with a front surface, wherein the front surface of the second fiber is arranged at the front surface of the elongated insert, wherein the front surface of the first optical fiber is arranged distally relative to the front surface of the second optical fiber; an operating means being shiftable between a first condition and a second condition; a console including a light source, a light detector and a processing unit for processing the signals provided by the light detector, wherein one of the light source and the light detector is connected with the first optical fiber and the other one of the light source and the light detector is connected with the second optical fiber; and a switch for activating optical measurements by the console; wherein the operating means is interconnected with the elongated insert and with the switch, so that when the operating means is in the first condition the second distal end portion is located within the hollow shaft and proximally to the bevel, and so that when the operating means is in the second condition the second distal end portion is located outside the hollow shaft and distally to the bevel; wherein the operating means includes a first lever and a second lever, wherein the first lever is rotatable between the first condition and the second condition, and wherein the second lever is arranged between the first lever and the elongated insert, so that a rotational movement of the first lever is converted in a translational movement of the elongated insert to shift the operating means between the first condition and the second condition; and wherein, the switch is configured to trigger the optical measurements due to a pushing of the first lever.