Apparatus and methods for controlled clot aspiration
A dynamic aspiration system includes a vacuum source, an aspiration catheter, a connecting tube, controllable valves to control a level of pressure in the aspiration catheter or the connecting tube, pressure sensors to detect pressure readings, and a controller capable of utilizing an artificial neural network (ANN) trained to predict flow state classifications. The controller may receive pressure readings from the sensors, provide the pressure readings as input data for the ANN, classify, via the ANN, a current flow state in the aspiration catheter or the connecting tube based on outputs generated by the ANN, and operate the controllable valves based on the classification of the current flow state. The controller operates the controllable valves in a first pressure protocol if the classification by the ANN is restricted or obstructed, and operates the controllable valves in a second pressure protocol if the classification by the ANN is unrestricted.
1 . A dynamic aspiration system for use with a vacuum source and an aspiration catheter, the system comprising:
a connecting tube configured to place the vacuum source and the aspiration catheter in fluid communication;
one or more controllable valves configured to control a level of pressure in the aspiration catheter or the connecting tube;
one or more sensors configured to detect one or more pressure readings associated with a flow state in the aspiration catheter or the connecting tube; and
a controller configured to utilize an artificial neural network (ANN) trained to predict flow state classifications in the connecting tube or the aspiration catheter, the controller being further configured to:
receive, from one or more of the sensors, one or more pressure readings;
provide, to the ANN, the one or more pressure readings as input data for the ANN;
classify, via the ANN, a current flow state in the aspiration catheter or the connecting tube based on one or more outputs generated by the ANN responsive to the one or more pressure readings being provided as input data for the ANN; and
operate one or more of the controllable valves based on the classification of the current flow state by the ANN, wherein the controller operates the controllable valves in a first pressure protocol if the classification by the ANN is restricted or obstructed, and wherein the controller operates the controllable valves in a second pressure protocol if the classification by the ANN is unrestricted.
2 . The dynamic aspiration system of claim 1 , wherein the second pressure protocol is a sampling protocol configured to open one or more of the controllable valves for a time interval to periodically sample the flow state in the aspiration catheter or the connecting tube.
3 . The dynamic aspiration system of claim 2 , wherein the controller includes a sampling delay between the classification by the ANN being unrestricted and opening the one or more controllable valves to sample the flow state.
4 . The dynamic aspiration system of claim 3 , wherein the sampling delay progressively changes in duration when the classification by the ANN continues to be unrestricted.
5 . The dynamic aspiration system of claim 1 , wherein one or more of the first pressure protocol or the second pressure protocol comprise one or more pressure pulses, wherein one or more of the pressure pulses associated with the first pressure protocol or the second pressure protocol generate one or more pressure differentials within the aspiration catheter or the connecting tube, and wherein a frequency and an amplitude of one or more of the pressure differentials is selected from a library of pressure pulses.
6 . The dynamic aspiration system of claim 5 , wherein the controller cycles through the library of pressure pulses, and then repeats one or more pressure pulses associated with a change in the flow state.
7 . The dynamic aspiration system of claim 1 , wherein one or more of the first pressure protocol or the second pressure protocol comprise one or more pressure pulses, and wherein the controller is further configured to determine, for each pressure pulse associated with the first pressure protocol or the second pressure protocol, a degree of success corresponding to a change in a flow rate in the aspiration catheter or the connecting tube responsive to the pressure pulse.
8 . The dynamic aspiration system of claim 7 , wherein the controller is further configured to operate one or more of the controllable valves in a third pressure protocol, wherein the third pressure protocol is determined based at least in part on the degrees of success respectively determined for the one or more pressure pulses of the first pressure protocol.
9 . The dynamic aspiration system of claim 1 , wherein one or more of the first pressure protocol or the second pressure protocol comprise one or more pressure pulses, wherein one or more of the pressure pulses associated with the first pressure protocol or the second pressure protocol generate one or more pressure differentials within the aspiration catheter or the connecting tube, and wherein the classification by the ANN of the current flow state in the aspiration catheter or the connecting tube is one of a plurality of flow states comprising (1) a restricted flow state, (2) an unrestricted flow state, (3) a clogged flow state, or (4) a partially clogged flow state.
10 . The dynamic aspiration system of claim 9 , wherein the pressure differentials associated with the first pressure protocol increase in magnitude while the classification by the ANN is a clogged flow state or a partially clogged flow state.
11 . The dynamic aspiration system of claim 9 , wherein a magnitude of the pressure differentials is held constant when the classification by the ANN is a restricted flow state.
12 . The dynamic aspiration system of claim 1 , wherein the connecting tube is linear in an unconstrained configuration, wherein a first end of the connecting tube is configured to be attached to the vacuum source, and wherein a second end of the connecting tube is configured to be attached to the aspiration catheter.
13 . The dynamic aspiration system of claim 12 , further comprising a pressure source and including a three-way joint configured to place the pressure source in fluid communication with the connecting tube, wherein the three-way joint includes an angled injection tube that directs fluid from the pressure source towards the second end of the connecting tube.
14 . The dynamic aspiration system of claim 1 , wherein classifying, via the ANN, the current flow state is based at least in part on one or more readings received from one or more of differential pressure sensors, magnetic flow sensors, acoustic flow sensors, ultrasonic sensors, optical flow sensors, thermal flow sensors, and sensors configured to detect circumferential expansion or contraction of the connecting tube.
15 . The dynamic aspiration system of claim 1 , wherein the controller is configured to hold one or more of the controllable valves open based on the first pressure protocol until the classification of the current flow state by the ANN is unrestricted.
16 . The dynamic aspiration system of claim 1 , wherein the pressure readings received from one or more of the sensors are analyzed by the controller to determine one or more local extrema based on one or more discrete portions of a data set, the local extrema comprising one or more of a local minimum pressure reading and a local maximum pressure reading.
17 . The dynamic aspiration system of claim 16 , wherein the local extrema are compared by the controller to one or more global extrema of the data set, the global extrema comprising one or more of a global minimum pressure reading and a global maximum pressure reading.
18 . The dynamic aspiration system of claim 16 , wherein one or more of the discrete portions of the data set are analyzed by the controller to determine one or more of a mean flow rate and a standard deviation of a flow rate associated with the connecting tube.
19 . The dynamic aspiration system of claim 1 , wherein the ANN uses a multinomial logistic regression algorithm to classify the current flow state.
20 . A dynamic aspiration method comprising:
receiving, by an automated controller, one or more pressure readings from one or more sensors associated with an aspiration catheter or connecting tube, wherein the connecting tube is configured to place a vacuum source and the aspiration catheter in fluid communication;
providing, by the automated controller, to an artificial neural network (ANN) trained to predict flow state classifications in the connecting tube or the aspiration catheter, the one or more pressure readings;
classifying, by the automated controller, via the ANN, a current flow state in the aspiration catheter or the connecting tube based on one or more outputs generated by the ANN responsive to the one or more pressure readings being provided as input data for the ANN; and
operating, by the automated controller, one or more controllable valves configured to control a level of pressure in the connecting tube based on the classification of the current flow state by the ANN, wherein the automated controller operates the controllable valves in a first pressure protocol if the classification by the ANN is restricted or obstructed, and wherein the automated controller operates the controllable valves in a second pressure protocol if the classification by the ANN is unrestricted.