Ultrasound endoscope

1 . An ultrasound endoscope comprising:

an insertion unit having a tip portion;

an observation window disposed in the insertion unit, an image pickup element disposed corresponding to the observation window;

a first three-way pipe and a second three-way pipe disposed in the insertion unit;

a treatment tool channel disposed within the insertion unit;

a signal cable disposed in the insertion unit and connected to the image pickup element,

wherein a first opening portion of the first three-way pipe and a second opening portion of the second three-way pipe are disposed on the tip portion, and the insertion unit has a first position on a proximal end thereof from the first opening portion,

wherein in a circular cross-section at the first position of the insertion unit, the treatment tool channel, the first three-way pipe, and the second three-way pipe are closer to an outer peripheral surface of the insertion unit than to the signal cable,

wherein in a circular cross-section, the first three-way pipe and the second three-way pipe are adjacent to each other,

wherein the first three-way pipe is branched into a plurality of first pipe portions, and the second three-way pipe is branched into a plurality of second pipe portions, and

wherein a first virtual surface where the plurality of first pipe portions is arranged and a second virtual surface where the plurality of second pipe portions is are arranged non-parallelly to each other.

2 . The ultrasound endoscope according to claim 1 , wherein in the circular cross-section, a first side is where the treatment tool channel is disposed with respect to the signal cable, and a second side is a side opposite to the first side, and

wherein a portion of the plurality of first pipe portions and the plurality of second pipe portions are disposed on the second side with respect to the signal cable.

3 . The ultrasound endoscope according to claim 2 , wherein, in the circular cross-section, a third side is where the first three-way pipe is disposed with respect to the signal cable, and a fourth side is a side opposite to the third side, and

wherein a portion of the second pipe portions is disposed on the fourth side with respect to the signal cable.

4 . The ultrasound endoscope according to claim 2 , wherein an ultrasound transducer is disposed at the tip portion, and an ultrasound cable is connected to the ultrasound transducer, and

wherein in the circular cross-section, the ultrasonic cable is disposed on the first side of the signal cable.

5 . The ultrasound endoscope according to claim 1 , further comprising:

a first merging portion of the plurality of first pipe portions;

a second merging portion of the plurality of first pipe portions;

a treatment tool passing through the treatment tool channel;

a standing base and a wire disposed at an outlet of the treatment tool channel,

wherein as the insertion unit is disposed in a linear manner, the insertion unit has a longitudinal axis,

wherein the wire is configured to be pulled to move the treatment tool upward together with the standing base,

wherein as the first merging portion and the second merging portion are projected on a vertical plane perpendicular to the longitudinal axis,

projected positions of the first merging portion and the second merging portion are shifted in a vertical direction and in left and right directions in relative to the vertical plane.

6 . The ultrasound endoscope according to claim 5 , wherein the first three-way pipe is arranged in an order of the plurality of first pipe portions, the first merging portion, and a first straight pipe portion sequentially from the proximal end,

wherein the second three-way pipe is arranged in an order of the plurality of second pipe portions, the second merging portion, a curved pipe portion, and second straight pipe portions sequentially from the proximal end, and

wherein the second merging portion is located closer to the proximal end than the first merging portion.

7 . The ultrasound endoscope according to claim 6 , wherein as the second straight pipe portions and the plurality of first pipe portions are projected onto the vertical plane, the second straight pipe portions and one of the plurality of first pipe portions are overlapped by the curved pipe portion.

8 . The ultrasound endoscope according to claim 1 , further comprising:

a first merging portion of the plurality of first pipe portions and a second merging portion of the plurality of second pipe portions,

wherein the first three-way pipe is arranged in an order of the plurality of first pipe portions, the first merging portion, and a first straight pipe portion sequentially from the proximal end, and the second three-way pipe is arranged in an order of the plurality of second pipe portions, the second merging portion, a curved pipe portion, and second straight pipe portions sequentially from the proximal end,

wherein as the insertion unit is disposed in a linear manner, the insertion unit has a longitudinal axis, and

wherein as the second straight pipe portions and the plurality of first pipe portions are projected onto a vertical plane perpendicular to the longitudinal axis, the second straight pipe portions and one of the plurality of first pipe portions are overlapped by the curved pipe portion.

9 . The ultrasound endoscope according to claim 8 , wherein the second merging portion is located closer to the proximal end than the first merging portion.

10 . The ultrasound endoscope according to claim 1 , further comprising:

a balloon mounting portion disposed at the tip portion to which a balloon is attached, wherein a first three-way tube is configured for supplying or discharging an ultrasound transmission medium to the balloon, and a second three-way tube is configured for supplying liquid and air to the observation window.

11 . The ultrasound endoscope according to claim 10 , wherein the balloon mounting portion is a locking groove.

12 . The ultrasound endoscope according to claim 1 , wherein the second three-way pipe is configured for supplying liquid and air to the observation window,

wherein in the circular cross-section, a first side is where the treatment tool channel is disposed with respect to the signal cable, and a second side is a side opposite to the first side, wherein the plurality of second pipe portions is provided on the second side with respect to the signal cable, and

wherein the second opening portion is on the first side with respect to the observation window.

13 . The ultrasound endoscope according to claim 12 , wherein in the circular cross-section, a third side is where the first three-way pipe is disposed with respect to the signal cable, and the second opening portion is disposed on the third side with respect to the observation window.