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

Abstract

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.

Fig. 1.

Ultrasound-assisted needle insertion guidance system. A camera is attached to the US probe to track position and orientation of probe and needle. Target (green circle) and needle guidance lines are overlaid on a 2D ultrasound image on the screen. Haptic actuators attached to the sides of the probe provide error cues if the probe is tilted away from a setpoint.

Fig. 2.

Vibration feedback system. Clear Guide SuperPROBE US probe uses cameras for visual tracking of probe and needle, and a silicone band with two embedded C-2 tactors for displaying vibration cues. (a) Side view of US probe with C-2 tactors. (b) Front view of US probe with C-2 tactors.

Fig. 3.

Pneumatic feedback system. Clear Guide SuperPROBE US probe uses cameras for visual tracking of probe and needle, and WRAP actuators for providing pneumatic guidance cues. (a) Side view of US probe with WRAP actuators. (b) Front view of US probe with WRAP actuators. (c) Diagram of WRAP actuators illustrating key features and geometry change from inflation.

Fig. 4.

Clinical setting study experimental setup showing US probe in a sterile cover with user wearing a sterile glove.

Fig. 5.

(a) Probe deviation averaged across each trial for vibration feedback system. Statistically significant differences are marked (* ≡ p ≤ 0.05). (b) Correction time averaged across each trial for vibration feedback system. Statistically significant differences are marked (*** ≡ p ≤ 0.001, ** ≡ p ≤ 0.01).

Fig. 6.

(a) Probe deviation averaged across each trial for pneumatic feed-back system. Statistically significant difference marked (* ≡ p ≤ 0.05). (b) Correction time averaged across each trial for pneumatic feedback system. Statistically significant difference marked (* ≡ p ≤ 0.05).

Fig. 7.

(a) Reaction time averaged across each trial for the clinical setting demonstration. Subjects responded faster to vibration cues than pneumatic cues (** ≡ p ≤ 0.01). (b) Trial time averaged across each trial for the clinical setting demonstration. The two feedback types were not statistically different.