The present protocol was part of a study approved by the Institutional Review Board at the University of Central Florida. Informed consent was received from all human participants for the present study. To be included in the study, participants had to be between 18 years and 75 years of age, play golf at least once per month for the past year or once per week for the past 2 months, have played golf for at least 2 years, and have had at least two episodes of low back pain in the past 12 months. The exclusion criteria were balance disorders, current pregnancy, surgery to the low back or lower extremities in the past year, or an open wound in the abdominal area where the transducer must be placed.
1. Ultrasound setup and data collection
<ol>
	<li>Open and turn on the ultrasound device (see Table of Materials) using the On/Off button.</li>
	<li>Press the Patient button on the keyboard to add a new patient and select New Patient on the left side of the screen.
	<ol>
		<li>Enter the desired patient ID number, ensure MSK is selected as the exam type, and click on Register. Exit to begin the exam and enter B-mode. 
		NOTE: Ultrasound settings in MSK Abdominal Preset, B-mode: B color = Tint Map D, Write Zoom Height = 4, Write Zoom Width = 4, Thermal Index = Tls, ATO Level = Low, Focus Number = 2, Focus Number CrossXBeam = 2, Focus Depth = 50, Depth (cm) = 3, Compression = 1, Focus Width = 1, Focus Width CrossXBeam = 1, Line Density = 3, Line Density CrossXBeam = 3, Suppression = 0, Frame Average = 4, From Average CrossXBeam = 2, CrossXBeam 2, CrossXBeam # = Low, CrossXBeam Type = Mean, Edge Enhance = 3, B Steer = 0, Gray Scale Map = Gray Map C, Gain = 34, Dynamic Range = 69, Rejection = 0, Frequency (MHz) = 12.</li>
	</ol>
	</li>
	<li>Position the linear array transducer in the elastic belt by placing the head of the linear transducer through a horizontal slit in the middle of the belt (see Table of Materials). Next, apply one to two foam blocks to secure the transducer in its place.
	<ol>
		<li>Apply ultrasound gel (see Table of Materials) to the linear transducer. Position the transducer on the lateral abdominal wall, approximately 10 cm lateral to the umbilicus8.</li>
		<li>Secure the belt to the participant using the hook and loop fasteners. Ensure the belt is tight enough so that the transducer is secured perpendicular to the lateral abdominal wall8.</li>
		<li>Adjust the depth and gain (brightness) of the ultrasound if necessary to obtain a clear image of the fascial borders and muscle thickness of the external oblique, internal oblique, and transverse abdominis. Ensure that the fascial border of the transverse abdominis is visible on the edge of the screen in this longitudinal view (Figure 1)8. 
		NOTE: The depth will depend on the size of the individual being measured, but ensure that the deep fascial border of the transverse abdominis is visible and the image is clear.</li>
		<li>Once the image is clear, position the patient in a manner that mirrors the task they will complete. For example, if they perform a golf swing, have them stand in their setup position. Press Freeze, then Store to capture a static image, save it to the patient&#39;s exam, and measure in real time or access it later to measure the resting muscle thickness. 
		NOTE: See Figure 1 for an example of a clear image of the lateral abdominal wall using B-mode ultrasound.</li>
	</ol>
	</li>
	<li>Select Freeze again to return to live imaging. Press Store to begin recording in B-mode video. On the bottom-right corner of the screen, check that a timer begins and is highlighted in bright green, indicating that a video is being captured. Instruct the participant to take a full golf swing once the recording has begun.
	<ol>
		<li>Press Store again to end the video and save it to their exam. 
		NOTE: Saved images and videos will appear below the active image, with up to five visible per row. Select the cursor to scroll through or select previous images.</li>
	</ol>
	</li>
	<li>Repeat step 1.4 as many times as necessary for the study. Adjust the positioning of the ultrasound probe within the foam block as needed if the image becomes blurry. 
	NOTE: Typical protocols comparing biofeedback and non-biofeedback conditions use between 3 and 10 repetitions per condition11,17.
	<ol>
		<li>After each trial, review the video for image clarity. If the image becomes anechoic (entirely black) at any point, it indicates that the ultrasound probe moved during the swing. In such a case, exclude the trial and re-measure.</li>
	</ol>
	</li>
	<li>Following each swing, have the patient positioned where they can view the ultrasound screen. Open the most recent trial.
	<ol>
		<li>Provide a brief overview and description of the muscles of interest (for a rotational task, this will include the external and internal obliques). Describe how the muscles should get thicker during the movement and show them their trial, providing education based on each attempt.</li>
		<li>For example, if the obliques stay relatively the same size throughout the task, instruct them to focus during the next attempt to contract their core muscles forcefully throughout the movement instead of passively rotating the trunk. 
		&#8203;NOTE: Emphasis on trunk rotation as a power source during a golf swing is a common trait of higher-skilled golfers18. During rotational movements, it is generally not feasible to provide biofeedback during the task. Therefore, providing feedback following each trial is thought to be acceptable19.</li>
	</ol>
	</li>
	<li>Repeat the biofeedback trials for as many attempts as desired. Provide the ultrasound images as well as verbal cueing or instruction following each attempt, adjusting the cueing as needed.</li>
</ol>
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/64333/64333fig01.jpg" /> 
Figure 1: Image of the right lateral abdominal wall during quiet standing. (A) External oblique. (B) Internal oblique. (C) Transverse abdominis. <a href="https://www.jove.com/files/ftp_upload/64333/64333fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
2. Resting image processing
<ol>
	<li>Open the first resting image to measure. Using the cursor, hover over the desired image from the library below the active image and click on Enter.
	<ol>
		<li>Click on Measure once to open the measurement tool. Click on Enter when the cursor is over the superior fascial border of the muscle of interest. 
		NOTE: For the present study, the external and internal obliques were measured as they are the muscles of interest, but one can also measure the transverse abdominis in this view.</li>
		<li>Click on Enter again once the cursor is over the inferior fascial border. 
		NOTE: The length of the measured segment will appear on the bottom-left portion of the screen, measured in centimeters. Record this length in a spreadsheet organized to include the participant or patient name/number and resting muscle thickness.</li>
	</ol>
	</li>
	<li>Repeat steps 2.1.1-2.1.2 for all the images needed to measure for both the external and internal obliques.</li>
</ol>
3. B-Mode video processing
<ol>
	<li>Once the desired number of videos have been captured, open the first video to be processed. Using the cursor, hover over the desired image from the library below the active image and click on the Enter button.</li>
	<li>Adjust the viewing frame within the B-mode video until the first frame is reached. Determine the desired sampling rate. 
	NOTE: Previous literature has used 10% intervals of the total frames from 0%-100% for analysis, but one may wish to use more or less depending on the aims20.</li>
	<li>Once there is the desired frame open, use the Measure tool. Click the button once to open the tool, place the cursor on the superior fascial border of the muscle of interest, and click on Enter to place the first end of the measurement.</li>
	<li>Drag the measurement line to the inferior fascial border of the muscle of interest and click on Enter again to complete the measurement. 
	NOTE: The distance measured will appear on the bottom-left portion of the screen.</li>
	<li>Press Store to save the measured image.</li>
	<li>Record the measurement in a spreadsheet organized to include participant or patient name/number, frame number, and thickness measurements. Return to the original B-mode video frame (step 3.2).</li>
	<li>Scroll to the next frame to be analyzed. For example, if one is sampling 11 time points (10% intervals from 0%-100%) of a swing that captured 100 frames, one will now use frame 10 (i.e., 10/100 corresponds to frame 10 out of 100 total frames).
	<ol>
		<li>Repeat steps 3.3-3.4 to measure the next frame.</li>
	</ol>
	</li>
	<li>Repeat step 3.7 until all the desired frames are measured.</li>
	<li>Move to the next video and repeat steps 3.1-3.8 until all the videos are measured. 
	&#8203;NOTE: See Figure 2 for a compilation of the processed frames throughout phases of a golf swing.</li>
</ol>
4. Activation ratio calculation
NOTE: An activation ratio is commonly used to determine the degree of muscle thickness change8,9,11. The formula for the activation ratio is contracted thickness (cm)/resting thickness (cm).
<ol>
	<li>To determine the activation ratio at a specific time point, measure the thickness by following step 3. Divide this value by the resting image thickness obtained from step 2.</li>
</ol>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/64333/64333fig02.jpg" /> 
Figure 2: Frame-by-frame analysis of a B-mode video on the trail side (right) lateral abdominal wall of a right-handed golfer. EO = external oblique; IO = internal oblique. <a href="https://www.jove.com/files/ftp_upload/64333/64333fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

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<li>Stokes, I. A. F., Henry, S. M., Single, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Surface+EMG+electrodes+do+not+accurately+record+from+lumbar+multifidus+muscles%5BTitle%5D)+AND+%22Clinical+Biomechanics%22%5BJournal%5D)">Surface EMG electrodes do not accurately record from lumbar multifidus muscles.</a> Clinical Biomechanics. 18 (1), 9-13 (2003).</li>
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The authors have no relevant disclosures to report.

Providing ultrasound biofeedback following a rotation-based sports movement such as a golf swing can be used to increase the muscle thickness of the lateral abdominal wall. As shown in the representative results, a single trial of ultrasound biofeedback can lead to short-term increases in oblique muscle activity throughout a golf swing.
Previous research has also used B-mode ultrasound secured with an elastic belt during dynamic tasks20. This was measured while individuals walked on a treadmill. Similar to the present methods, the authors reduced the B-mode video to a smaller percentage of still images for measurement to represent the walking gait cycle. This makes data processing and analysis more feasible, as they are sampled at 10% intervals throughout a gait cycle. The current protocol builds upon this methodology by applying B-mode ultrasound as a biofeedback tool during a complex, rotation-based movement. However, since gait is cyclical, direct comparison to this protocol must be cautioned. A golf swing can be broken down into smaller portions, such as the address, backswing, downswing, and follow-through21. However, it can be challenging to synchronize B-mode ultrasound video to the specific phases of the golf swing because the backswing of elite players averages under 1 s, and the downswing averages less than 0.25 s21. To directly compare swing phases, the clinician can view the changes in muscle activity by synchronizing a swing video and the B-mode ultrasound video. The swing and ultrasound images can then be compared frame-by-frame to determine the muscle activity at various points in the swing. Synchronizing the B-mode video to a stopwatch with lapped times at the start and end of the swing can also provide a rough estimate of swing phases. As the backswing begins, one can expect the trail side (right side in a right-handed golfer) internal oblique to increase in thickness as they rotate the trunk toward the right side during the backswing. Similarly, the lead side (left in right-handed golfers) external oblique should increase in thickness during the backswing, as there is contralateral trunk rotation during this phase of the swing21. See Figure 2 for a frame-by-frame comparison of oblique activity throughout the phases of the golf swing.
A critical step is to ensure consistent skin contact with the transducer to obtain accurate, clear images during rotational movements. This may require troubleshooting or modifications in the foam blocks used. For example, larger or smaller individuals may need different amounts of padding, so it is advised to confirm image clarity prior to data collection. Instruct the individual to perform a few practice swings, which allows them to familiarize themselves with the positioning while the clinician observes the ultrasound screen to ensure image clarity. Since the transducer will be secured with an elastic belt wrapped tightly around the abdomen, this familiarization period is important. It allows the individual to become comfortable with the equipment and swing as normally as possible. The belt may alter their mechanics minimally, but it will allow for a consistently clear image.
Additional limitations of this methodology include the potential for unclear images. While the risk for unclear images can be mitigated with proper positioning and familiarization periods, some frames throughout the B-mode video may be unclear. When choosing the sampling rate or determining what percentage of frames will be measured, some adjustments may need to be made to ensure clear images are analyzed. For example, if every 10th frame is measured, starting with frame 1, the investigator and/or clinician might have to choose a frame slightly out of sequence if the desired image is out of focus-such as using the 12th frame rather than the 11th. Maintaining consistent contact between the skin and transducer is essential to reduce the risk of poor image quality. Video 1 shows an example of a full B-mode video. When paused at different time points, the viewer can see how, even when proper procedures are followed, there are occasional blurry frames. Despite these challenges, dynamic ultrasound assessments are reliable measures12.
In addition to the current methodology for image processing performed on the ultrasound device, other processing software can measure thickness changes12. For example, saving the videos to an external drive and opening them on a computer with freely available measurement software allows later processing without needing the ultrasound device. A similar procedure is used with this type of software, where screenshots of the desired frames are taken from the video and then analyzed using a measurement tool. If using this method, ensure to set the scale of images, using the depth measurements on the right side of the ultrasound image as a reference line.
Training participants with ultrasound biofeedback requires a sound understanding of anatomy, familiarization with the ultrasound device, and the ability to explain the image or video to a participant in real time22,23. This method of ultrasound biofeedback is considered augmented feedback with knowledge of performance, where the patient is given additional information (video of their muscle activity) that shows what they did while completing the movement. In injured populations, augmented feedback can provide missing information due to changes in sensory pathways19. Augmented feedback can enhance learning and decrease the amount of practice needed to learn a complex task19. The timing of biofeedback has been debated, and one limitation of this methodology is that concurrent feedback seems to be most effective19. However, providing feedback during a swing is not feasible due to the nature of ultrasound imaging and the golf swing. Therefore, providing post-swing feedback is a reasonable alternative. Lastly, the ideal frequency of biofeedback training has not been established24, and future studies should compare long-term feedback training to determine the most effective strategy.
While the current protocol focuses on the golf swing, a similar methodology could be followed for other sports focusing on trunk rotation. These include tennis, baseball, and softball, among others. Since these also involve a rotational component, the lateral abdominal wall can be targeted similarly, and ultrasound can be used for biofeedback. This protocol focuses on the golf swing due to the high prevalence of low back pain in golfers, commonly attributed to the rapid rotation of the trunk combined with lateral shear and compressive forces4. Future research should investigate whether training with ultrasound biofeedback can improve muscle activity patterns and reduce the risk of low back pain in golf and other rotation-based sports.

The muscles of the lateral abdominal wall include the external oblique, internal oblique, and transverse abdominis. The external obliques perform lateral flexion and contralateral&#160;trunk rotation, while the internal obliques perform ipsilateral&#160;trunk rotation. The transverse abdominis is the deepest layer of the abdominal musculature, and it functions to increase intra-abdominal pressure and increase the segmental stability of the spine1. The proper function of these muscles is important to reduce low back pain risk and improve athletic performance as core stability allows for increased strength and power through the extremities2.
During sports with an emphasis on trunk rotation, such as golf, tennis, baseball, or softball, there is a high demand for the core muscles. For example, during a golf swing, the obliques on the trail side of the body peak at 64% of the maximal voluntary isometric contraction (MVIC) when measured using surface electromyography, while the lead obliques peak at 54% MVIC3. Trunk rotation is a key contributor to the distance and accuracy of golf shots4. The stresses of the golf swing and the high demand for core muscle activity may contribute to low back pain, which is the most common injury in golf5. Additionally, in elite golfers with low back pain, the timing of external oblique activity is delayed during the golf swing compared to healthy individuals6. Another study using electromyography found golfers with low back pain have an earlier onset of the erector spinae than golfers without low back pain7, suggesting a focus on anterolateral muscles may be beneficial. Therefore, measuring the extent and timing of abdominal muscle activity during a golf swing is important to improve performance and reduce the risk of low back pain.
Rehabilitative ultrasound is commonly used to assess lateral abdominal wall muscles due to the layered nature of this musculature8,9,10. There is no difference in transverse abdominis activation in college golfers with and without low back pain in the supine position or in a more functional golf swing setup position11. However, transverse abdominis activity is only one component of a golf swing, and rotation may be more important for this population. Previous literature has used an elastic belt and foam block to secure the ultrasound transducer to the abdomen, allowing for ultrasound assessment of the core musculature during dynamic movement such as a single leg squat or gait8. Applying ultrasound during dynamic movements has been shown to have acceptable to excellent reliability12. This technique can be applied to measure thickness changes in the lateral abdominal wall during a golf swing or other sport-specific task. While surface electromyography is commonly used to measure the electrical activity of muscles, this is less feasible in the abdominal region. The layered anatomy leads to cross-talk between the muscles and does not allow for a visual representation of the individual muscle layers of the core13. Ultrasound provides an advantage over alternatives like surface electromyography for the core musculature because it allows for a representation of each individual muscle while also giving an image for feedback14.
Since ultrasound provides an image of the muscles of interest in real time, it can also be used as a tool for visual biofeedback. Ultrasound biofeedback has improved the ability to increase the muscle thickness of the transverse abdominis and lumbar multifidus compared to verbal cueing alone15,16. Additionally, in golfers with and without low back pain, real-time ultrasound biofeedback increases transverse abdominis thickness in supine and in the golf-setup position11. Biofeedback training in supine also translates to upright loaded tasks17. More research is needed to determine the required frequency and duration of biofeedback training, as most studies are single-session or short-term training protocols15. Since ultrasound has been applied during functional tasks and there is evidence that golfers can increase deep muscle pre-activation in the setup position, research should next investigate the use of ultrasound biofeedback to increase oblique muscle thickness during the golf swing.
Therefore, this methodology aims to use ultrasound as a feedback mechanism to improve the activation and timing of the abdominal obliques during the golf swing.

<table><tbody><tr><td>Aquasonic 100</td><td>Parker</td><td>BT-025-0037L</td><td>Ultrasound gel</td></tr><tr><td>GE NextGen Logig e Ultrasound Unit</td><td>GE Healthcare</td><td>HR48382AR</td><td></td></tr><tr><td>Linear Array Probe</td><td>GE Healthcare</td><td>H48062AB</td><td></td></tr><tr><td>Velcro straps</td><td>VELCRO</td><td></td><td>Fasteners for the elastic belt used to secure the ultrasound transducer</td></tr></tbody></table>

providing visual biofeedback using brightness mode ultrasound during a golf swing

Using ultrasound biofeedback in conjunction with verbal cueing can increase muscle thickness more than verbal cueing alone and may augment traditional rehabilitation techniques in an athletic, physically active population. Brightness mode (B-mode) ultrasound can be applied using frame-by-frame analysis synchronized with video to understand muscle thickness changes during these dynamic tasks. Visual biofeedback with ultrasound has been established in static positions for the muscles of the lateral abdominal wall. However, by securing the transducer to the abdomen using an elastic belt and foam block, biofeedback can be applied during more specific tasks prevalent in lifetime sports, such as golf. To analyze muscle activity during a golf swing, muscle thickness changes can be compared. The thickness must increase throughout the task, indicating that the muscle is more active. This methodology allows clinicians to immediately replay ultrasound videos for patients as a visual tool to instruct proper activity of the muscles of interest. For example, ultrasound can be used to target the external and internal obliques, which play an important role in swinging a golf club or any other rotational sport or activity. This methodology aims to increase oblique muscle thickness during the golf swing. Additionally, the timing of muscle contraction can be targeted by instructing the patient to contract the abdominal muscles at specific time points, such as the beginning of the downswing, with the goal of improving muscle firing patterns during tasks.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td></td>
			<td>Non-feedback</td>
			<td></td>
			<td></td>
			<td>Biofeedback</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Swing Duration</td>
			<td>External Oblique Thickness (cm)</td>
			<td>Internal Oblique Thickness (cm)</td>
			<td>Combined Oblique Thickness (cm)</td>
			<td>External Oblique Thickness (cm)</td>
			<td>Internal Oblique Thickness (cm)</td>
			<td>Combined Oblique Thickness (cm)</td>
		</tr>
		<tr>
			<td>0.0%</td>
			<td>0.630</td>
			<td>0.978</td>
			<td>1.608</td>
			<td>0.446</td>
			<td>1.109</td>
			<td>1.555</td>
		</tr>
		<tr>
			<td>12.5%</td>
			<td>0.609</td>
			<td>1.043</td>
			<td>1.652</td>
			<td>0.565</td>
			<td>1.446</td>
			<td>2.011</td>
		</tr>
		<tr>
			<td>25.0%</td>
			<td>0.870</td>
			<td>1.533</td>
			<td>2.403</td>
			<td>0.598</td>
			<td>1.370</td>
			<td>1.968</td>
		</tr>
		<tr>
			<td>37.5%</td>
			<td>0.620</td>
			<td>0.696</td>
			<td>1.316</td>
			<td>0.674</td>
			<td>1.174</td>
			<td>1.848</td>
		</tr>
		<tr>
			<td>50.0%</td>
			<td>0.859</td>
			<td>0.826</td>
			<td>1.685</td>
			<td>0.587</td>
			<td>1.152</td>
			<td>1.739</td>
		</tr>
		<tr>
			<td>62.5%</td>
			<td>0.652</td>
			<td>1.022</td>
			<td>1.674</td>
			<td>0.880</td>
			<td>1.326</td>
			<td>2.206</td>
		</tr>
		<tr>
			<td>75.0%</td>
			<td>0.837</td>
			<td>1.022</td>
			<td>1.859</td>
			<td>0.761</td>
			<td>1.511</td>
			<td>2.272</td>
		</tr>
		<tr>
			<td>87.5%</td>
			<td>0.717</td>
			<td>0.859</td>
			<td>1.576</td>
			<td>0.772</td>
			<td>0.761</td>
			<td>1.533</td>
		</tr>
		<tr>
			<td>100.0%</td>
			<td>0.685</td>
			<td>0.859</td>
			<td>1.544</td>
			<td>0.598</td>
			<td>1.304</td>
			<td>1.902</td>
		</tr>
	</tbody>
</table>
Table 1: Comparison of the combined oblique thickness throughout a golf swing between the non-feedback and ultrasound biofeedback conditions.
For the desired result, the measures of oblique thickness must be larger during biofeedback trials compared to traditional, non-feedback swings. Ideally, this would occur throughout all phases of the golf swing. Multiple trials can be used, and each trial is discussed before the next attempt. Typical protocols comparing biofeedback and non-biofeedback conditions use between 3 and 10 repetitions per condition11,17. For example, based on the trial in Table 1, the clinician&#39;s next instructions to the patient must be for them to target the obliques and increase trunk rotational power during the backswing. This participant&#39;s combined thickness of the obliques decreased at the 25% time point during the biofeedback trial, which corresponds with approximately the middle of the backswing. At most other points, the obliques were larger during the biofeedback trial, which suggests the patient understands how to use their obliques during the golf swing effectively.
In the present example, 5% of the images were used for sampling. There were 180 frames captured during the swing, and 9 were measured to represent the phases of the golf swing, as seen in Figure 2. If desired, the sampling rate could be increased to represent a larger percentage of the ultrasound video. This would simply require analysis of more images as described in the &#34;B-Mode video processing&#34; section of the protocol.
To calculate whether the biofeedback trials were effective, one can compare the activation ratios at different time points of the swing. An activation ratio takes the contracted thickness, or thickness during the swing, and divides it by the resting (or setup) thickness. A ratio above 1.0 indicates the muscle increased in thickness and is active. For example, the 0% swing duration in Table 1 can be used as the resting thickness, as this is the thickness of the external and internal obliques before the swing is initiated. To determine whether the combined oblique thickness increased at the 50% time point when biofeedback was provided, activation ratios can be calculated as follows:
Non-biofeedback: 1.685 cm/1.608 cm = 1.048
Biofeedback: 1.739 cm/1.555 cm = 1.118
Based on this individual sample, it can be inferred that biofeedback led to a small increase in oblique muscle activation at the 50% duration of the golf swing.
Video 1: Full B-mode ultrasound video of the right lateral abdominal wall during a golf swing of a right-handed golfer. <a href="https://www.jove.com/files/ftp_upload/64333/Figure 3.wmv" target="_blank">Please click here to download this Video.</a>

Watch this Scientific Journal Video about Providing Visual Biofeedback Using Brightness Mode Ultrasound During a Golf Swing at JoVE.com

Providing Visual Biofeedback Using Brightness Mode Ultrasound During a Golf Swing

Brightness mode ultrasound can be used to provide visual biofeedback of the muscles of the lateral abdominal wall during a golf swing. Post-swing visual and verbal instruction can increase the muscle activation and timing of the external and internal obliques.

Using ultrasound biofeedback in conjunction with verbal cueing can increase muscle thickness more than verbal cueing alone and may augment traditional ...

providing-visual-biofeedback-using-brightness-mode-ultrasound-during

Nanyang Technological University

Research

JoVE Journal

Medicine

2.0K Views.  University of Central Florida. Brightness mode ultrasound can be used to provide visual biofeedback of the muscles of the lateral abdominal wall during a golf swing. Post-swing visual and verbal instruction can increase the muscle activation and timing of the external and internal obliques.

Video: Providing Visual Biofeedback Using Brightness Mode Ultrasound During a Golf Swing

Vision Training Methods for Sports Concussion Mitigation and Management

There is emerging evidence supporting the use vision training, including light board training tools, as a concussion baseline and neuro-diagnostic tool and potentially as a supportive component to concussion prevention strategies. This paper is focused on providing detailed methods for select vision training tools and reporting normative data for comparison when vision training is a part of a sports management program. The overall program includes standard vision training methods including tachistoscope, Brock&#8217;s string, and strobe glasses, as well as specialized light board training algorithms. Stereopsis is measured as a means to monitor vision training affects. In addition, quantitative results for vision training methods as well as baseline and post-testing *A and Reaction Test measures with progressive scores are reported. Collegiate athletes consistently improve after six weeks of training in their stereopsis, *A and Reaction Test scores. When vision training is initiated as a team wide exercise, the incidence of concussion decreases in players who participate in training compared to players who do not receive the vision training. Vision training produces functional and performance changes that, when monitored, can be used to assess the success of the vision training and can be initiated as part of a sports medical intervention for concussion prevention.

This paper describes a protocol to conduct, quantitatively monitor, and assess the success of vision training initiated as part of a sports medical management program including intervention for concussion prevention and performance enhancement.

There is emerging evidence supporting the use vision training, including light board training tools, as a concussion baseline and neuro-diagnostic tool ...

Behavior

Real-time fMRI Biofeedback Targeting the Orbitofrontal Cortex for Contamination Anxiety

We present a method for training subjects to control activity in a region of their orbitofrontal cortex associated with contamination anxiety using biofeedback of real-time functional magnetic resonance imaging (rt-fMRI) data. Increased activity of this region is seen in relationship with contamination anxiety both in control subjects1 and in individuals with obsessive-compulsive disorder (OCD),2 a relatively common and often debilitating psychiatric disorder involving contamination anxiety. Although many brain regions have been implicated in OCD, abnormality in the orbitofrontal cortex (OFC) is one of the most consistent findings.3, 4 Furthermore, hyperactivity in the OFC has been found to correlate with OCD symptom severity5 and decreases in hyperactivity in this region have been reported to correlate with decreased symptom severity.6 Therefore, the ability to control this brain area may translate into clinical improvements in obsessive-compulsive symptoms including contamination anxiety. Biofeedback of rt-fMRI data is a new technique in which the temporal pattern of activity in a specific region (or associated with a specific distributed pattern of brain activity) in a subject's brain is provided as a feedback signal to the subject. Recent reports indicate that people are able to develop control over the activity of specific brain areas when provided with rt-fMRI biofeedback.7-12 In particular, several studies using this technique to target brain areas involved in emotion processing have reported success in training subjects to control these regions.13-18 In several cases, rt-fMRI biofeedback training has been reported to induce cognitive, emotional, or clinical changes in subjects.8, 9, 13, 19 Here we illustrate this technique as applied to the treatment of contamination anxiety in healthy subjects. This biofeedback intervention will be a valuable basic research tool: it allows researchers to perturb brain function, measure the resulting changes in brain dynamics and relate those to changes in contamination anxiety or other behavioral measures. In addition, the establishment of this method serves as a first step towards the investigation of fMRI-based biofeedback as a therapeutic intervention for OCD. Given that approximately a quarter of patients with OCD receive little benefit from the currently available forms of treatment,20-22 and that those who do benefit rarely recover completely, new approaches for treating this population are urgently needed.

Here we present a method for training people to control a brain area involved in contamination anxiety and for probing the relationship between contamination anxiety and brain connectivity patterns.

We present a method for training subjects to control activity in a region of their orbitofrontal cortex associated with contamination anxiety using ...

Ultrasound Images of the Tongue: A Tutorial for Assessment and Remediation of Speech Sound Errors

Diagnostic ultrasound imaging has been a common tool in medical practice for several decades. It provides a safe and effective method for imaging structures internal to the body. There has been a recent increase in the use of ultrasound technology to visualize the shape and movements of the tongue during speech, both in typical speakers and in clinical populations. Ultrasound imaging of speech has greatly expanded our understanding of how sounds articulated with the tongue (lingual sounds) are produced. Such information can be particularly valuable for speech-language pathologists. Among other advantages, ultrasound images can be used during speech therapy to provide (1) illustrative models of typical (i.e.&#160;&#34;correct&#34;) tongue configurations for speech sounds, and (2) a source of insight into the articulatory nature of deviant productions. The images can also be used as an additional source of feedback for clinical populations learning to distinguish their better productions from their incorrect productions, en route to establishing more effective articulatory habits.
Ultrasound feedback is increasingly used by scientists and clinicians as both the expertise of the users increases and as the expense of the equipment declines. In this tutorial, procedures are presented for collecting ultrasound images of the tongue in a clinical context. We illustrate these procedures in an extended example featuring one common error sound, American English /r/. Images of correct and distorted /r/ are used to demonstrate (1) how to interpret ultrasound images, (2) how to assess tongue shape during production of speech sounds, (3), how to categorize tongue shape errors, and (4), how to provide visual feedback to elicit a more appropriate and functional tongue shape. We present a sample protocol for using real-time ultrasound images of the tongue for visual feedback to remediate speech sound errors. Additionally, example data are shown to illustrate outcomes with the procedure.

Ultrasound imaging can be used to display the shape and movements of the tongue in real time during speech. The images can be used to determine the nature of speech sound errors. Visual feedback of the tongue can be used to facilitate improvements in speech sound production in clinical populations.

Diagnostic ultrasound imaging has been a common tool in medical practice for several decades. It provides a safe and effective method for imaging ...

A Vibrotactile Feedback Device for Seated Balance Assessment and Training

Postural perturbations, motion tracking, and sensory feedback are modern techniques used to challenge, assess, and train upright sitting, respectively. The goal of the developed protocol is to construct and operate a sitting platform that can be passively destabilized while an inertial measurement unit quantifies its motion and vibrating elements deliver tactile feedback to the user. Interchangeable seat attachments alter the stability level of the device to safely challenge sitting balance. A built-in microcontroller allows fine-tuning of the feedback parameters to augment sensory function. Posturographic measures, typical of balance assessment protocols, summarize the motion signals acquired during timed balance trials. No dynamic sitting protocol to date provides variable challenge, quantification, and sensory feedback free of laboratory constraints. Our results demonstrate that non-disabled users of the device exhibit significant changes in posturographic measures when balance difficulty is altered or vibrational feedback provided. The portable, versatile device has potential applications in rehabilitation (following skeletal, muscular, or neurological injury), training (for sports or spatial awareness), entertainment (via virtual or augmented reality), and research (of sitting-related disorders).

A sitting platform has been developed and assembled that passively destabilizes sitting posture in humans. During the user&#39;s stabilizing task, an inertial measurement unit records the device&#39;s motion, and vibrating elements deliver performance-based feedback to the seat. The portable, versatile device may be used in rehabilitation, assessment, and training paradigms.

Postural perturbations, motion tracking, and sensory feedback are modern techniques used to challenge, assess, and train upright sitting, respectively. ...

A Human-machine-interface Integrating Low-cost Sensors with a Neuromuscular Electrical Stimulation System for Post-stroke Balance Rehabilitation

A stroke is caused when an artery carrying blood from heart to an area in the brain bursts or a clot obstructs the blood flow to brain thereby preventing delivery of oxygen and nutrients. About half of the stroke survivors are left with some degree of disability. Innovative methodologies for restorative neurorehabilitation are urgently required to reduce long-term disability. The ability of the nervous system to reorganize its structure, function and connections as a response to intrinsic or extrinsic stimuli is called neuroplasticity. Neuroplasticity is involved in post-stroke functional disturbances, but also in rehabilitation. Beneficial neuroplastic changes may be facilitated with non-invasive electrotherapy, such as neuromuscular electrical stimulation (NMES) and sensory electrical stimulation (SES). NMES involves coordinated electrical stimulation of motor nerves and muscles to activate them with continuous short pulses of electrical current while SES involves stimulation of sensory nerves with electrical current resulting in sensations that vary from barely perceivable to highly unpleasant. Here, active cortical participation in rehabilitation procedures may be facilitated by driving the non-invasive electrotherapy with biosignals (electromyogram (EMG), electroencephalogram (EEG), electrooculogram (EOG)) that represent simultaneous active perception and volitional effort. To achieve this in a resource-poor setting, e.g., in low- and middle-income countries, we present a low-cost human-machine-interface (HMI) by leveraging recent advances in off-the-shelf video game sensor technology. In this paper, we discuss the open-source software interface that integrates low-cost off-the-shelf sensors for visual-auditory biofeedback with non-invasive electrotherapy to assist postural control during balance rehabilitation. We demonstrate the proof-of-concept on healthy volunteers.

A novel low-cost human-machine interface for interactive post-stroke balance rehabilitation system is presented in this article. The system integrates off-the-shelf low-cost sensors towards volitionally driven electrotherapy paradigm. The proof-of-concept software interface is demonstrated on healthy volunteers.

A stroke is caused when an artery carrying blood from heart to an area in the brain bursts or a clot obstructs the blood flow to brain thereby preventing ...

Neuroscience

Multispectral Optoacoustic Tomography for Functional Imaging in Vascular Research

Microcirculatory impairment has been recognized in various disease processes, underlying this growing theme within vascular research. In recent years, the development of live imaging systems has set the (analytical) pace in both basic and clinical research, with the objective of creating new instruments capable of providing real-time, quantifiable endpoints with clinical interest and application. Near-infrared spectroscopy (NIRS), positron emission tomography (PET), computed tomography (CT), and magnetic resonance imaging (MRI) are available, among other techniques, but cost, image resolution, and reduced contrast are recognized as common challenges. Optoacoustic tomography (OT) offers a new perspective on vascular functional imaging, combining state-of-the-art optical absorption and spatial resolution capacities (from micrometer optical to millimeter acoustic resolution) with tissue depth. In this study, we tested the applicability of multispectral optoacoustic tomography (MSOT) for functional imaging. The system uses a tunable optical parametric oscillator (OPO) pumped by an Nd: YAG laser, providing excitation pulses sensed by a 3D probe at wavelengths from 680 nm to 980 nm. Images obtained from the human forearm were reconstructed through a specific algorithm (supplied within the manufacturer&#39;s software) based on the response of specific chromophores. Maximal Oxygenated Hemoglobin (Max HbO2) and Deoxygenated Hemoglobin (Max Hb), Total Hemoglobin (HbT), and mean Oxygen Saturation (mSO2) to vascular density (&#181;Vu), inter-unit average distances (&#950;Ad), and capillary blood volume (mm3) may be measured using this system. The applicability potential found with this OT system is relevant. Ongoing software developments will surely improve the utility of this imaging system.

The present protocol describes the acquisition of multispectral optoacoustic images of in vivo human skin vasculature. These include the quantification of hemoglobin and melanin, regarded as chromophores of interest for functional analysis.

Microcirculatory impairment has been recognized in various disease processes, underlying this growing theme within vascular research. In recent years, the ...

Bioengineering

Motor Imagery Using VR Digital Avatars in a Brain-Computer Interface System

Motor Imagery Performance Through Embodied Digital Twins in a Virtual Reality-Enabled Brain-Computer Interface Environment

This study introduces an innovative framework for neurological rehabilitation by integrating brain-computer interfaces (BCI) and virtual reality (VR) technologies with the customization of three-dimensional (3D) avatars. Traditional approaches to rehabilitation often fail to fully engage patients, primarily due to their inability to provide a deeply immersive and interactive experience. This research endeavors to fill this gap by utilizing motor imagery (MI) techniques, where participants visualize physical movements without actual execution. This method capitalizes on the brain's neural mechanisms, activating areas involved in movement execution when imagining movements, thereby facilitating the recovery process. The integration of VR's immersive capabilities with the precision of electroencephalography (EEG) to capture and interpret brain activity associated with imagined movements forms the core of this system. Digital Twins in the form of personalized 3D avatars are employed to significantly enhance the sense of immersion within the virtual environment. This heightened sense of embodiment is crucial for effective rehabilitation, aiming to bolster the connection between the patient and their virtual counterpart. By doing so, the system not only aims to improve motor imagery performance but also seeks to provide a more engaging and efficacious rehabilitation experience. Through the real-time application of BCI, the system allows for the direct translation of imagined movements into virtual actions performed by the 3D avatar, offering immediate feedback to the user. This feedback loop is essential for reinforcing the neural pathways involved in motor control and recovery. The ultimate goal of the developed system is to significantly enhance the effectiveness of motor imagery exercises by making them more interactive and responsive to the user's cognitive processes, thereby paving a new path in the field of neurological rehabilitation.

Author Spotlight: Enhancing Neurorehabilitation Through EEG, Motor Imagery, and Virtual Reality

Motor imagery in a virtual reality environment has wide applications in brain-computer interface systems. This manuscript outlines the use of personalized digital avatars that resemble the participants performing movements imagined by the participant in a virtual reality environment to enhance immersion and a sense of body ownership.

This study introduces an innovative framework for neurological rehabilitation by integrating brain-computer interfaces (BCI) and virtual reality (VR) ...

Objectively Assessing Sports Concussion Utilizing Visual Evoked Potentials

A portable system capable of measuring steady-state visual-evoked potentials (SSVEP) was developed to provide an objective, quantifiable method of electroencephalogram (EEG) testing following a traumatic event. In this study, the portable system was used on 65 healthy rugby players throughout a season to determine whether SSVEP are a reliable electrophysiological biomarker for concussion. Preceding the competition season, all players underwent a baseline SSVEP assessment. During the season, players were re-tested within 72 h of a match for either test-retest reliability or post-injury assessment. In the case of a medically diagnosed concussion, players were reassessed again once deemed recovered by a physician. The SSVEP system consisted of a smartphone housed in a VR-frame delivering a 15 Hz flicker stimulus, while a wireless EEG headset recorded occipital activity. Players were instructed to stare at the screen's fixation point while remaining seated and quiet. Electrodes were arranged according to the 10-20 EEG-positioning nomenclature, with O1-O2 being the recording channels while P1-P2 the references and bias, respectively. All EEG data was processed using a Butterworth bandpass filter, Fourier transformation, and normalization to convert data for frequency analysis. Players SSVEP responses were quantified into a signal-to-noise ratio (SNR), with 15 Hz being the desired signal, and summarized into respective study groups for comparison. Concussed players were seen to have a significantly lower SNR compared to their baseline; however, post-recovery, their SNR was not significantly different from the baseline. Test-retest indicated high device reliability for the portable system. An improved portable SSVEP system was also validated against an established EEG amplifier to ensure the investigative design is capable of obtaining research quality EEG measurements. This is the first study to identify differences in SSVEP responses in amateur athletes following a concussion and indicates the potential for SSVEP as an aid in concussion assessment and management.

A portable system capable of measuring steady-state visual-evoked potentials was developed and trialed on 65 amateur rugby players over 18 weeks to investigate SSVEP as a potential electrophysiological biomarker for concussion. Players' baselines were measured pre-season, with retesting for reliability, concussion, and recovery assessment being conducted within controlled time-periods, respectively.

A portable system capable of measuring steady-state visual-evoked potentials (SSVEP) was developed to provide an objective, quantifiable method of ...

Restoring Post-Stroke Motor Function by Motor Imagery Brain-Computer Interface

Motor Imagery Brain-Computer Interface in Rehabilitation of Upper Limb Motor Dysfunction After Stroke

The rehabilitation effect of patients with moderate or severe upper limb motor dysfunction after stroke is poor, which has been the focus of research owing to the difficulties encountered. Brain-computer interface (BCI) represents a hot frontier technology in brain neuroscience research. It refers to the direct conversion of the sensory perception, imagery, cognition, and thinking of users or subjects into actions, without reliance on peripheral nerves or muscles, to establish direct communication and control channels between the brain and external devices. Motor imagery brain-computer interface (MI-BCI) is the most common clinical application of rehabilitation as a non-invasive means of rehabilitation. Previous clinical studies have confirmed that MI-BCI positively improves motor dysfunction in patients after stroke. However, there is a lack of clinical operation demonstration. To that end, this study describes in detail the treatment of MI-BCI for patients with moderate and severe upper limb dysfunction after stroke and shows the intervention effect of MI-BCI through clinical function evaluation and brain function evaluation results, thereby providing ideas and references for clinical rehabilitation application and mechanism research.

Author Spotlight: Using Motor Imagery Brain-Computer Interface to Improve Motor and Cognitive Function in Stroke Patients

The purpose of this study is to provide an important reference for the standard clinical operation of motor imagery brain-computer interface (MI-BCI) for upper limb motor dysfunction after stroke.

The rehabilitation effect of patients with moderate or severe upper limb motor dysfunction after stroke is poor, which has been the focus of research ...

Muscle Function Obtained with Motion Mode Ultrasound and Surface Electromyography during Core Endurance Exercise

Motion mode (M-mode) ultrasound allows researchers and clinicians to measure the change of muscle thickness across time. Muscle thickness can be measured between fascial borders at a given time point during an exercise. This selected time point produces a one-dimensional image resulting in real-time, live observation of anatomy. Ultrasound used during functional movement can be referred to as dynamic ultrasound; this is feasible and reliable with the use of a linear transducer, elastic belt, and foam block to secure consistent transducer placement. The lateral abdominal wall is commonly investigated using ultrasound due to the overlapping nature of the muscles. Surface electromyography (sEMG) can complement M-mode ultrasound imaging because it measures the electrical representation of muscle activation. There is minimal evidence using M-mode ultrasound and sEMG simultaneously during core exercise. Exercises that challenge the core musculature involve both isometric holds (e.g., side plank), as well as oscillatory extremity movements (e.g., dead bug). In this study, both instruments will be used simultaneously to measure core muscle function during exercise. Ultrasound measurements will be obtained using a linear transducer and ultrasound unit, and sEMG measurements will be acquired from a wireless sEMG system. To make comparisons between participants and exercises, normalization methods using static, exercise starting positions for both instruments will be used. An activation ratio will be used for ultrasound and calculated by dividing the contracted thickness (thickness during a time point of exercise) by the rested (starting position) thickness. Muscle thickness will be measured in centimeters from the superior inferior fascial border to inferior superior fascial border. These methods aim to offer an innovative and practical measurement of muscle function with M-mode ultrasound and sEMG during core endurance exercises.

This protocol uses motion mode ultrasound and surface electromyography simultaneously to measure muscle function of the core. Muscle thickness and activation of the local stabilizers (e.g., transverse abdominis, internal oblique) and global movers (e.g., external oblique) is achievable during specific time points of the side plank and dead bug exercises.

Motion mode (M-mode) ultrasound allows researchers and clinicians to measure the change of muscle thickness across time. Muscle thickness can be measured ...