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.remotexs.ntu.edu.sg/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.remotexs.ntu.edu.sg/files/ftp_upload/64333/64333fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

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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 border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<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.remotexs.ntu.edu.sg/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

1.9K 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

Using Visual and Narrative Methods to Achieve Fair Process in Clinical Care

The Institute of Medicine has targeted patient-centeredness as an important area of quality improvement. A major dimension of patient-centeredness is respect for patient's values, preferences, and expressed needs. Yet specific approaches to gaining this understanding and translating it to quality care in the clinical setting are lacking. From a patient perspective quality is not a simple concept but is best understood in terms of five dimensions: technical outcomes; decision-making efficiency; amenities and convenience; information and emotional support; and overall patient satisfaction. Failure to consider quality from this five-pronged perspective results in a focus on medical outcomes, without considering the processes central to quality from the patient's perspective and vital to achieving good outcomes. In this paper, we argue for applying the concept of fair process in clinical settings. Fair process involves using a collaborative approach to exploring diagnostic issues and treatments with patients, explaining the rationale for decisions, setting expectations about roles and responsibilities, and implementing a core plan and ongoing evaluation. Fair process opens the door to bringing patient expertise into the clinical setting and the work of developing health care goals and strategies. This paper provides a step by step illustration of an innovative visual approach, called photovoice or photo-elicitation, to achieve fair process in clinical work with acquired brain injury survivors and others living with chronic health conditions. Applying this visual tool and methodology in the clinical setting will enhance patient-provider communication; engage patients as partners in identifying challenges, strengths, goals, and strategies; and support evaluation of progress over time. Asking patients to bring visuals of their lives into the clinical interaction can help to illuminate gaps in clinical knowledge, forge better therapeutic relationships with patients living with chronic conditions such as brain injury, and identify patient-centered goals and possibilities for healing. The process illustrated here can be used by clinicians, (primary care physicians, rehabilitation therapists, neurologists, neuropsychologists, psychologists, and others) working with people living with chronic conditions such as acquired brain injury, mental illness, physical disabilities, HIV/AIDS, substance abuse, or post-traumatic stress, and by leaders of support groups for the types of patients described above and their family members or caregivers.

This paper illustrates an innovative visual approach (photovoice or photo-elicitation) to achieve fair process in clinical care for patients living with chronic health conditions, illuminate gaps in clinical knowledge, forge better therapeutic relationships, and identify patient-centered goals and possibilities for healing.

The Institute of Medicine has targeted patient-centeredness as an important area of quality improvement. A major dimension of patient-centeredness is ...

MRI-guided Disruption of the Blood-brain Barrier using Transcranial Focused Ultrasound in a Rat Model

Focused ultrasound (FUS) disruption of the blood-brain barrier (BBB) is an increasingly investigated technique for circumventing the BBB1-5. The BBB is a significant obstacle to pharmaceutical treatments of brain disorders as it limits the passage of molecules from the vasculature into the brain tissue to molecules less than approximately 500 Da in size6. FUS induced BBB disruption (BBBD) is temporary and reversible4 and has an advantage over chemical means of inducing BBBD by being highly localized. FUS induced BBBD provides a means for investigating the effects of a wide range of therapeutic agents on the brain, which would not otherwise be deliverable to the tissue in sufficient concentration. While a wide range of ultrasound parameters have proven successful at disrupting the BBB2,5,7, there are several critical steps in the experimental procedure to ensure successful disruption with accurate targeting. This protocol outlines how to achieve MRI-guided FUS induced BBBD in a rat model, with a focus on the critical animal preparation and microbubble handling steps of the experiment.

Microbubble-mediated focused ultrasound disruption of the blood-brain barrier (BBB) is a promising technique for non-invasive targeted drug delivery in the brain1-3. This protocol outlines the experimental procedure for MRI-guided transcranial BBB disruption in a rat model.

Focused ultrasound (FUS) disruption of the blood-brain barrier (BBB) is an increasingly investigated technique for circumventing the BBB1-5. The BBB is a ...

Driving Simulation in the Clinic: Testing Visual Exploratory Behavior in Daily Life Activities in Patients with Visual Field Defects

Patients suffering from homonymous hemianopia after infarction of the posterior cerebral artery (PCA) report different degrees of constraint in daily life, despite similar visual deficits. We assume this could be due to variable development of compensatory strategies such as altered visual scanning behavior. Scanning compensatory therapy (SCT) is studied as part of the visual training after infarction next to vision restoration therapy. SCT consists of learning to make larger eye movements into the blind field enlarging the visual field of search, which has been proven to be the most useful strategy1, not only in natural search tasks but also in mastering daily life activities2. Nevertheless, in clinical routine it is difficult to identify individual levels and training effects of compensatory behavior, since it requires measurement of eye movements in a head unrestrained condition. Studies demonstrated that unrestrained head movements alter the visual exploratory behavior compared to a head-restrained laboratory condition3. Martin et al.4 and Hayhoe et al.5 showed that behavior demonstrated in a laboratory setting cannot be assigned easily to a natural condition. Hence, our goal was to develop a study set-up which uncovers different compensatory oculomotor strategies quickly in a realistic testing situation: Patients are tested in the clinical environment in a driving simulator. SILAB software (Wuerzburg Institute for Traffic Sciences GmbH (WIVW)) was used to program driving scenarios of varying complexity and recording the driver's performance. The software was combined with a head mounted infrared video pupil tracker, recording head- and eye-movements (EyeSeeCam, University of Munich Hospital, Clinical Neurosciences).
The positioning of the patient in the driving simulator and the positioning, adjustment and calibration of the camera is demonstrated. Typical performances of a patient with and without compensatory strategy and a healthy control are illustrated in this pilot study. Different oculomotor behaviors (frequency and amplitude of eye- and head-movements) are evaluated very quickly during the drive itself by dynamic overlay pictures indicating where the subjects gaze is located on the screen, and by analyzing the data. Compensatory gaze behavior in a patient leads to a driving performance comparable to a healthy control, while the performance of a patient without compensatory behavior is significantly worse. The data of eye- and head-movement-behavior as well as driving performance are discussed with respect to different oculomotor strategies and in a broader context with respect to possible training effects throughout the testing session and implications on rehabilitation potential.

Patients with visual deficits after stroke report about different constraints in daily life most likely due to variable compensatory strategies, which are difficult to differentiate in clinical routine. We present a clinical set-up which allows measurement of different compensatory head- and eye-movement-strategies and evaluating their effects on driving performance.

Patients suffering from homonymous hemianopia after infarction of the posterior cerebral artery (PCA) report different degrees of constraint in daily ...

A Novel Application of Musculoskeletal Ultrasound Imaging

Ultrasound is an attractive modality for imaging muscle and tendon motion during dynamic tasks and can provide a complementary methodological approach for biomechanical studies in a clinical or laboratory setting. Towards this goal, methods for quantification of muscle kinematics from ultrasound imagery are being developed based on image processing. The temporal resolution of these methods is typically not sufficient for highly dynamic tasks, such as drop-landing. We propose a new approach that utilizes a Doppler method for quantifying muscle kinematics. We have developed a novel vector tissue Doppler imaging (vTDI) technique that can be used to measure musculoskeletal contraction velocity, strain and strain rate with sub-millisecond temporal resolution during dynamic activities using ultrasound. The goal of this preliminary study was to investigate the repeatability and potential applicability of the vTDI technique in measuring musculoskeletal velocities during a drop-landing task, in healthy subjects. The vTDI measurements can be performed concurrently with other biomechanical techniques, such as 3D motion capture for joint kinematics and kinetics, electromyography for timing of muscle activation and force plates for ground reaction force. Integration of these complementary techniques could lead to a better understanding of dynamic muscle function and dysfunction underlying the pathogenesis and pathophysiology of musculoskeletal disorders.

We describe a new ultrasound-based vector tissue Doppler imaging technique to measure muscle contraction velocity, strain and strain rate with sub-millisecond temporal resolution during dynamic activities. This approach provides complementary measurements of dynamic muscle function and could lead to a better understanding of mechanisms underlying musculoskeletal disorders.

Ultrasound is an attractive modality for imaging muscle and tendon  motion during dynamic tasks and can provide a complementary methodological  approach ...

DNBS/TNBS Colitis Models: Providing Insights Into Inflammatory Bowel Disease and Effects of Dietary Fat

Inflammatory Bowel Diseases (IBD), including Crohn&#39;s Disease and Ulcerative Colitis, have long been associated with a genetic basis, and more recently host immune responses to microbial and environmental agents. Dinitrobenzene sulfonic acid (DNBS)-induced colitis allows one to study the pathogenesis of IBD associated environmental triggers such as stress and diet, the effects of potential therapies, and the mechanisms underlying intestinal inflammation and mucosal injury. In this paper, we investigated the effects of dietary n-3 and n-6 fatty acids on the colonic mucosal inflammatory response to DNBS-induced colitis in rats. All rats were fed identical diets with the exception of different types of fatty acids [safflower oil (SO), canola oil (CO), or fish oil (FO)] for three&#160;weeks prior to exposure to intrarectal DNBS. Control rats given intrarectal ethanol continued gaining weight over the 5 day study, whereas, DNBS-treated rats fed lipid diets all lost weight with FO and CO fed rats demonstrating significant weight loss by 48&#160;hr and rats fed SO by 72&#160;hr. Weight gain resumed after 72&#160;hr post DNBS, and by 5 days post DNBS, the FO group had a higher body weight than SO or CO groups. Colonic sections collected 5&#160;days post DNBS-treatment showed focal ulceration, crypt destruction, goblet cell depletion, and mucosal infiltration of both acute and chronic inflammatory cells that differed in severity among diet groups. The SO fed group showed the most severe damage followed by the CO, and FO fed groups that showed the mildest degree of tissue injury. Similarly, colonic myeloperoxidase (MPO) activity, a marker of neutrophil activity was significantly higher in SO followed by CO fed rats, with FO fed rats having significantly lower MPO activity. These results demonstrate the use of DNBS-induced colitis, as outlined in this protocol, to determine the impact of diet in the pathogenesis of IBD.

DNBS/TNBS induced colitis offers an alternative and inexpensive method to study the pathobiology of inflammatory bowel disease. The protocol discussed in this paper outlines the successful application of DNBS to induce colitis in mice and rats and allows one to thoroughly study host-mediated intestinal responses.

Inflammatory Bowel Diseases (IBD), including Crohn&#39;s Disease and Ulcerative Colitis, have long been associated with a genetic basis, and more recently ...

Measuring Ascending Aortic Stiffness In Vivo in Mice Using Ultrasound

We present a protocol for measuring in vivo aortic stiffness in mice using high-resolution ultrasound imaging. Aortic diameter is measured by ultrasound and aortic blood pressure is measured invasively with a solid-state pressure catheter. Blood pressure is raised then lowered incrementally by intravenous infusion of vasoactive drugs phenylephrine and sodium nitroprusside. Aortic diameter is measured for each pressure step to characterize the pressure-diameter relationship of the ascending aorta. Stiffness indices derived from the pressure-diameter relationship can be calculated from the data collected. Calculation of arterial compliance is described in this protocol.
This technique can be used to investigate mechanisms underlying increased aortic stiffness associated with cardiovascular disease and aging. The technique produces a physiologically relevant measure of stiffness compared to ex vivo approaches because physiological influences on aortic stiffness are incorporated in the measurement. The primary limitation of this technique is the measurement error introduced from the movement of the aorta during the cardiac cycle. This motion can be compensated by adjusting the location of the probe with the aortic movement as well as making multiple measurements of the aortic pressure-diameter relationship and expanding the experimental group size.

Measuring Ascending Aortic Stiffness In Vivo in Mice Using Ultrasound

We describe a technique for measuring aortic stiffness from its pressure-diameter relationship in vivo in mice. Aortic diameter is recorded by ultrasound and aortic pressure is measured invasively with a solid-state pressure catheter. Blood pressure is changed incrementally and the resulting diameter is measured.

We present a protocol for measuring in vivo aortic stiffness in mice using high-resolution ultrasound imaging. Aortic diameter is measured by ultrasound ...

In Vivo Dynamics of Retinal Microglial Activation During Neurodegeneration: Confocal Ophthalmoscopic Imaging and Cell Morphometry in Mouse Glaucoma

Microglia, which are CNS-resident neuroimmune cells, transform their morphology and size in response to CNS damage, switching to an activated state with distinct functions and gene expression profiles. The roles of microglial activation in health, injury and disease remain incompletely understood due to their dynamic and complex regulation in response to changes in their microenvironment. Thus, it is critical to non-invasively monitor and analyze changes in microglial activation over time in the intact organism. In vivo studies of microglial activation have been delayed by technical limitations to tracking microglial behavior without altering the CNS environment. This has been particularly challenging during chronic neurodegeneration, where long-term changes must be tracked. The retina, a CNS organ amenable to non-invasive live imaging, offers a powerful system to visualize and characterize the dynamics of microglia activation during chronic disorders.
This protocol outlines methods for long-term, in vivo imaging of retinal microglia, using confocal ophthalmoscopy (cSLO) and CX3CR1GFP/+ reporter mice, to visualize microglia with cellular resolution. Also, we describe methods to quantify monthly changes in cell activation and density in large cell subsets (200-300 cells per retina). We confirm the use of somal area as a useful metric for live tracking of microglial activation in the retina by applying automated threshold-based morphometric analysis of in vivo images. We use these live image acquisition and analyses strategies to monitor the dynamic changes in microglial activation and microgliosis during early stages of retinal neurodegeneration in a mouse model of chronic glaucoma. This approach should be useful to investigate the contributions of microglia to neuronal and axonal decline in chronic CNS disorders that affect the retina and optic nerve.

In Vivo Dynamics of Retinal Microglial Activation During Neurodegeneration: Confocal Ophthalmoscopic Imaging and Cell Morphometry in Mouse Glaucoma

Microglia activation and microgliosis are key responses to chronic neurodegeneration. Here, we present methods for in vivo, long-term visualization of retinal CX3CR1-GFP+ microglial cells by confocal ophthalmoscopy, and for threshold and morphometric analyses to identify and quantify their activation. We monitor microglial changes during early stages of age-related glaucoma.

Microglia, which are CNS-resident neuroimmune cells, transform their morphology and size in response to CNS damage, switching to an activated state with ...

A Simple Mechanical Procedure to Create Limbal Stem Cell Deficiency in Mouse

Limbal stem cell deficiency (LSCD) is a state of malfunction or loss of limbal epithelial stem cells, after which the corneal epithelium is replaced with conjunctiva. Patients suffer from recurrent corneal defects, pain, inflammation, and loss of vision.
Previously, a murine model of LSCD was described and compared to two other models. The goal was to produce a consistent mouse model of LSCD that both mimics the phenotype in humans and lasts long enough to make it possible to study the disease pathophysiology and to evaluate new treatments. Here, the technique is described in more detail.
A motorized tool with a rotating burr has been designed to remove the rust rings from the corneal surface or to smooth the pterygium bed in patients. It is a suitable device to create the desired LSCD model. It is a readily available, easy-to-use tool with a fine tip that makes it appropriate for working on small eyes, as in mice. Its application prevents unnecessary trauma to the eye and it does not result in unwanted injuries, as often is the case with chemical injury models. As opposed to a blunt scraper, it removes the epithelium with the basement membrane. In this protocol, the limbal area was abraded two times, and then the whole corneal epithelium was shaved from limbus to limbus. To avoid stroma injury, care was taken not to brush the corneal surface once the epithelium was already removed.

The following article provides an easy, reproducible technique to effectively create a sustainable mouse model of limbal stem cell deficiency (LSCD). This animal model is useful in testing and comparing the efficacy of treatments for limbal stem cell diseases.

Limbal stem cell deficiency (LSCD) is a state of malfunction or loss of limbal epithelial stem cells, after which the corneal epithelium is replaced with ...

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 ...

Continuous Venous-Arterial Doppler Ultrasound During a Preload Challenge

A preload challenge (PC) is a clinical maneuver that, first, increases the cardiac filling (i.e., preload) and, second, calculates the change in cardiac output. Fundamentally, a PC is a bedside approach for testing the Frank-Starling-Sarnoff (i.e., "cardiac function") curve. Normally, this curve has a steep slope such that a small change in the cardiac preload generates a large change in the stroke volume (SV) or cardiac output. However, in various disease states, the slope of this relationship flattens such that increasing the volume into the heart leads to little rise in the SV. In this pathological scenario, additional cardiac preload (e.g., intravenous fluid) is unlikely to be physiologically effective and could lead to harm if organ congestion evolves. Therefore, inferring both the cardiac preload and output is clinically useful as it may guide intravenous (IV) fluid resuscitation. Accordingly, the goal of this protocol is to describe a method for contemporaneously tracking the surrogates of cardiac preload and output using a novel, wireless, wearable ultrasound during a well-validated preload challenge.

The Frank-Starling-Sarnoff curve is clinically important and describes the relationship between cardiac preload and output. This report illustrates a novel method of simultaneous jugular venous and carotid arterial Doppler velocimetry as transient surrogates of cardiac preload and output, respectively; this approach is enabled by wireless, wearable Doppler ultrasound.

A preload challenge (PC) is a clinical maneuver that, first, increases the cardiac filling (i.e., preload) and, second, calculates the change in cardiac ...