Design and Evaluation of Haptic Guidance in Ultrasound-Based Needle-Insertion Procedures.

OBJECTIVE: This article presents two haptic guidance systems designed to help a clinician keep an ultrasound probe steady when completing ultrasound-assisted needle insertion tasks. These procedures demand spatial reasoning and hand-eye coordination because the clinician must align a needle with the ultrasound probe and extrapolate the needle trajectory using only a 2D ultrasound image. Past research has shown that visual guidance helps the clinician align the needle, but does not help the clinician keep the ultrasound probe steady, sometimes resulting in a failed procedure. METHODS: We created two separate haptic guidance systems to provide feedback if the user tilts the ultrasound probe away from the desired setpoint using (1) vibrotactile stimulation provided by a voice coil motor or (2) distributed tactile pressure provided by a pneumatic mechanism. RESULTS: Both systems significantly reduced probe deviation and correction time to errors during a needle insertion task. We also tested the two feedback systems in a more clinically relevant setup and showed that the perceptibility of the feedback was not affected by the addition of a sterile bag placed over the actuators and gloves worn by the user. CONCLUSION: These studies show that both types of haptic feedback are promising for helping the user keep the ultrasound probe steady during ultrasound-assisted needle insertion tasks. Survey results indicated that users preferred the pneumatic system over the vibrotactile system. SIGNIFICANCE: Haptic feedback may improve user performance in ultrasound-based needle-insertion procedures and shows promise in training for needle-insertion tasks and other medical procedures where guidance is required.

Needle guidance using handheld stereo vision and projection for ultrasound-based interventions.

With real-time instrument tracking and in-situ guidance projection directly integrated in a handheld ultrasound imaging probe, needle-based interventions such as biopsies become much simpler to perform than with conventionally-navigated systems. Stereo imaging with needle detection can be made sufficiently robust and accurate to serve as primary navigation input. We describe the low-cost, easy-to-use approach used in the Clear Guide ONE generic navigation accessory for ultrasound machines, outline different available guidance methods, and provide accuracy results from phantom trials.

First 3D ultrasound scanning, planning, and execution of CT-free milling interventions with a surgical robot.

Surgical procedures with navigation or robot system support usually require pre-operative planning data. This data can be acquired with imaging techniques such as computed tomography (CT), the current gold standard due to its high precision. With such planning data, access trajectories, implant positions, individual milling paths etc. can be computed. We present a novel ultrasound-based method to generate equivalent 3D image data which is well-suited for many interventions, but less costly than the CT-based method. The method is demonstrated for robot-based implant bed milling in the lateral skull base, in a complete process consisting of infrared navigation registration, manual ultrasound scan path delineation, path smoothing and checking, robot-based ultrasound scan execution, 3D ultrasound volume reconstruction, implant position optimization, robot milling path planning, and intervention execution. This represents, to the best of our knowledge, the first time such a CT-free, 3D-ultrasound-based intervention has been demonstrated in the laboratory.