This work is supported by grants of OU General Fund G110 and Research Excellence Fund of Biomedical Research and OSU-HRS Fund 013000. The authors would like to thank Lauren Chen for her assistance in preparing this manuscript.

All procedures involving animal subjects were approved and completed in accordance and compliance with The Ohio State University Institutional Animal Care and Use Committee (IACUC) regulations and guidelines.
1.&#160;Mouse Anesthesia
<ol>
	<li>Set up a clean procedure table with a heated isothermal pad wrapped in a surgical towel. The heating pad should be maintained between 30 &#176;C and 34 &#176;C to stabilize the animal&#39;s core temperature while reducing potential stress to the animal.</li>
	<li>Place the mouse in an anesthesia induction chamber with the following parameters: oxygen flow rate set to 1.5 L/min and isoflurane vaporizer set to 3.5%. Complete sedation should take place within 1-2 min. If an induction chamber is not available, a bell jar may be used with a wire mesh positioned at the bottom to avoid direct animal contact with the isoflurane.</li>
	<li>Immediately remove the mouse from the induction chamber once it is completely anesthetized (achieved when the mouse loses voluntary motor function). Apply a nose-cone to the animal for maintenance of anesthesia. The oxygen flow rate should be reduced to approximately 0.5 L/min and the isoflurane vaporizer should be set within the range of 1.5 to 2.5%.
	<ol>
		<li>Apply a small amount of ophthalmic ointment directly to the corneas to reduce eye dryness8. In addition, during anesthesia, the mouse should maintain an absence of the pedal withdrawal reflex, the mucous membranes should remain a pink color, and breathing should appear steady.</li>
	</ol>
	</li>
</ol>
2.&#160;Preparing for Diagnostic Ultrasound Imaging Procedure
<ol>
	<li>Restrain each leg of the mouse on the heated procedure table with a removable adhesive, such as surgical tape.</li>
	<li>Using an electric razor, remove the hair on the ventral body surface between the abdomen and half way up the thoracic cavity. Apply hair removal cream to further remove the remaining hair that is not cut by the razor. Wipe off the cream with a damp gauze pad after 2-3 min.</li>
	<li>Remove the excess hair using a water-moistened gauze pad and clean the shaved region with 70% alcohol or equivalent antiseptic. The ultrasound probe will be applied to this area to visualize diaphragm function. A topical analgesic may be provided to animals experiencing minor skin irritation due to hair removal.</li>
</ol>
3.&#160;Diagnostic Ultrasound Imaging Protocol
<ol>
	<li>Turn on the ultrasound device and adjust the output power (if necessary) on the apparatus by percentage to obtain optimum resolution.</li>
	<li>Set the ultrasound machine to either B (brightness)-mode, M (motion)-mode, or both before imaging, which allows for proper visualization of the mouse diaphragm contraction.</li>
	<li>Apply a small amount of ultrasound gel on the mouse&#39;s upper abdomen and massage the gel toward the thoracic cavity.</li>
	<li>Place the ultrasound transducer in this area and angle it upward towards the heart. Adjust the probe until an optimized resolution of the image is achieved. Note: for this protocol, a micro-convex array or linear phased array transducer is an ideal probe to use due to the small footprint and excellent axial resolution9; the frequency needs to be adjusted across the bandwidth and for these experiments a range of 6.5-12 MHz may be utilized.</li>
	<li>Press the freeze button to temporarily save the diaphragm images and view the selected contractions.</li>
	<li>Save the recording as a cine loop, which allows for later measurements of diaphragmatic excursion as well as respiration rate. Note: frames of images can be saved in the computer memory or on an external hard drive for future analysis9.
	<ol>
		<li>Precisely measure the depth of diaphragm movement from relaxation to contraction using the electronic calipers&#160;that are part of the ultrasound software.</li>
		<li>Convert the cine loop file into a MPEG file and determine the respiration rate by counting the number of diaphragmatic contractions during the recording period. Alternatively, the number of contractions per min (respiration rate) may be counted from the M-mode image.</li>
	</ol>
	</li>
</ol>
4.&#160;Post Anesthesia Animal Recovery
<ol>
	<li>The mouse should completely recover from anesthesia within 1 hour. Do not leave the animal unattended until it has regained sufficient consciousness to maintain sternal recumbency.</li>
</ol>

<ol>
	<li>Snyder, C. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Complementarity+of+ultrasound+and+fluorescence+imaging+in+an+orthotopic+mouse+model+of+pancreatic+cancer.">Complementarity of ultrasound and fluorescence imaging in an orthotopic mouse model of pancreatic cancer.</a> BMC Cancer. 9, 106 (2009).</li><li>Franchi, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non-invasive+assessment+of+cardiac+function+in+a+mouse+model+of+renovascular+hypertension.">Non-invasive assessment of cardiac function in a mouse model of renovascular hypertension.</a> Hypertension Research: Official Journal of the Japanese Society of Hypertension. , (2013).</li><li>Coatney, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrasound+imaging:+principles+and+applications+in+rodent+research.">Ultrasound imaging: principles and applications in rodent research.</a> ILAR Journal / National Research Council, Institute of Laboratory Animal Resources. 42, 233-247 (2001).</li><li>Morenz, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+of+air+trapping+in+chronic+obstructive+pulmonary+disease+by+low+frequency+ultrasound.">Detection of air trapping in chronic obstructive pulmonary disease by low frequency ultrasound.</a> BMC Pulmonary Medicine. 12, 8 (2012).</li><li>Gilliam, L. A., Moylan, J. S., Ann Callahan, L., Sumandea, M. P., Reid, M. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Doxorubicin+causes+diaphragm+weakness+in+murine+models+of+cancer+chemotherapy.">Doxorubicin causes diaphragm weakness in murine models of cancer chemotherapy.</a> Muscle &amp; Nerve. 43, 94-102 (2011).</li><li>Ferreira, L. F., Campbell, K. S., Reid, M. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effectiveness+of+sulfur-containing+antioxidants+in+delaying+skeletal+muscle+fatigue.">Effectiveness of sulfur-containing antioxidants in delaying skeletal muscle fatigue.</a> Medicine and Science in Sports and Exercise. 43, 1025-1031 (2011).</li><li>Zuo, L., Clanton, T. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reactive+oxygen+species+formation+in+the+transition+to+hypoxia+in+skeletal+muscle.">Reactive oxygen species formation in the transition to hypoxia in skeletal muscle.</a> American Journal of Physiology. Cell Physiology. 289, 207-216 (2005).</li><li>Helms, M. N., Torres-Gonzalez, E., Goodson, P., Rojas, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+tracheal+instillation+of+solutes+into+mouse+lung.">Direct tracheal instillation of solutes into mouse lung.</a> J. Vis. Exp. , (2010).</li><li>Hedrick, W. R., Hykes, D. L., Starchman, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Ultrasound Physics and Instrumentation. , 445 (2005).</li><li>von Sarnowski, B., Khaw, A. V., Kessler, C., Schminke, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+a+microconvex+array+transducer+for+the+ultrasonographic+examination+of+the+intrathoracic+segments+of+the+supraaortic+arteries.">Evaluation of a microconvex array transducer for the ultrasonographic examination of the intrathoracic segments of the supraaortic arteries.</a> Journal of Neuroimaging: Official Journal of the American Society of Neuroimaging. 20, 246-250 (2010).</li><li>Stocksley, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Abdominal Ultrasound. , 7-8 (2001).</li><li>Kremkau, F. W., Taylor, K. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Artifacts+in+ultrasound+imaging.">Artifacts in ultrasound imaging.</a> Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine. 5, 227-237 (1986).</li><li>Kremkau, F. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diagnostic+Ultrasound:+Principles+and+Instruments.">Diagnostic Ultrasound: Principles and Instruments.</a> Saunders Elsevier. , 521 (2006).</li><li>Laing, F. C., Kurtz, A. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+importance+of+ultrasonic+side-lobe+artifacts.">The importance of ultrasonic side-lobe artifacts.</a> Radiology. 145, 763-768 (1982).</li><li>Abu-Zidan, F. M., Hefny, A. 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The authors declare that they have no competing financial interests.

The current experimental protocol develops diagnostic ultrasound imaging techniques specific to the diaphragm activity in a mouse model via a non-invasive, in vivo approach. The anesthesia apparatus settings are approximated values, which may be slightly adjusted for each animal since individual mice may respond differently to anesthesia. To prevent improper anesthesia administration, it is important to regularly monitor the mouse&#39;s vital signs including the heart rate, respiration rate, and body temperature...

Recently, diagnostic ultrasound imaging techniques have been applied to mouse models of renovascular hypertension and pancreatic cancer1,2.&#160;However, these techniques have not been widely used in rodent respiratory muscle function assay. Therefore, we have developed a diagnostic ultrasound imaging method as a valuable tool for in vivo longitudinal assessments of diaphragm mobility in mice.
There are several advantages to diagnostic ultrasound imaging. For instance, it is noninvasive, safe, portable, and allows for real time measurements at a relatively low cost3. Particularly, certain low frequency ultrasound devices were able to detect air trapping, a clinical characteristic of chronic obstructive pulmonary disease (COPD) with mild to severe airflow limitation4. Thus, diagnostic ultrasound imaging may serve as an easily accessible and reproducible screening method for real-time monitoring of respiratory disorders.
Diagnostic ultrasound imaging techniques are frequently applied to larger animals or human subjects. However, there have been a limited number of ultrasound imaging studies on mouse models, which is likely due to the challenges of performing ultrasound on small-scale subjects. The current protocol outlines a novel procedure for measuring diaphragm function in the mouse. In addition, although there have been several rodent studies on diaphragm function, most of the results were generated by isolating muscle strips directly from the euthanized animal5-7. In contrast, using an in vivo diagnostic ultrasound imaging method for analyzing diaphragm activity would decrease the number of animals sacrificed for experimentation. Furthermore, long-term treatments focused on enhancing diaphragm contractility may be accurately assessed via ultrasound in rodent models without sacrificing animals.
In our lab, we have developed an effective method for visualizing as well as analyzing mouse diaphragm activity using an ultrasound machine, which helps the understanding of diaphragm function in vivo, avoids invasive methods to animals, and aids in the development of therapeutic treatments for respiratory dysfunction.

<table border="0" cellpadding="0" cellspacing="0" width="602">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="127">
			<td height="127" style="height:127px;width:147px;">Veterinary digital ultrasonic diagnostic imaging system</td>
			<td style="width:111px;">Edan</td>
			<td style="width:151px;">DUS 3 VET</td>
			<td style="width:196px;">Ultrasound parameters include: frequency of 6.5 MHz, Depth of 29 mm. Note: An equivalent ultrasound machine may be used for this protocol</td>
		</tr>
		<tr height="38">
			<td height="38" style="height:38px;width:147px;">Micro-convex array transducer</td>
			<td>Edan</td>
			<td>C611</td>
			<td>Or equivalent</td>
		</tr>
		<tr height="38">
			<td height="38" style="height:38px;width:147px;">GE Logiq i hand-carried unit (HCU)&#160;</td>
			<td>GE Healthcare</td>
			<td style="width:151px;">GE Logiq i hand-carried unit (HCU)&#160;</td>
			<td>Or equivalent</td>
		</tr>
		<tr height="38">
			<td height="38" style="height:38px;width:147px;">GE 12 MHz linear array probe</td>
			<td>GE Healthcare</td>
			<td style="width:151px;">12L-RS</td>
			<td>Or equivalent</td>
		</tr>
		<tr height="171">
			<td height="171" style="height:171px;width:147px;">Veterinary anesthetic vaporizer</td>
			<td style="width:111px;">Webster Veterinary</td>
			<td>Serial #: W422021</td>
			<td style="width:196px;">Isoflurane was exclusively used with this vaporizer (or equivalent). A custom made induction chamber for anesthesia was assembled for initial anesthesia. Maintenance anesthesia was performed using a nose cone</td>
		</tr>
		<tr height="38">
			<td height="38" style="height:38px;width:147px;">Isothesia (Isoflurane, USP)</td>
			<td>Butler Schein</td>
			<td>29405 250ML PVL</td>
			<td>Or equivalent</td>
		</tr>
		<tr height="57">
			<td height="57" style="height:57px;width:147px;">Enviro-pure anesthesia absorbing canister</td>
			<td style="width:111px;">Surgivet Smiths Medical PM, Inc.</td>
			<td>Part #: 32373B10</td>
			<td>Or equivalent</td>
		</tr>
		<tr height="38">
			<td height="38" style="height:38px;width:147px;">Ultrasound transmission gel</td>
			<td>HM Sonic</td>
			<td>N/A</td>
			<td>Or equivalent&#160;</td>
		</tr>
		<tr height="38">
			<td height="38" style="height:38px;width:147px;">Puralube vet ointment</td>
			<td>Puralube&#160;</td>
			<td>NDC 17033-211-38</td>
			<td>Or equivalent</td>
		</tr>
		<tr height="38">
			<td height="38" style="height:38px;width:147px;">Deltaphase isothermal pad</td>
			<td style="width:111px;">Braintree Scientific Inc.</td>
			<td>39DP</td>
			<td>Or equivalent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hair remover</td>
			<td>Nair</td>
			<td>N/A</td>
			<td>Or equivalent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Electric razor</td>
			<td>Remington</td>
			<td>HC-5015</td>
			<td>Or equivalent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Surgical tape</td>
			<td>3M Micropore</td>
			<td>1530-1</td>
			<td>Or equivalent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Gauze sponges</td>
			<td>Dynarex</td>
			<td>3262</td>
			<td>Or equivalent</td>
		</tr>
	</tbody>
</table>

diagnostic ultrasound imaging of mouse diaphragm function

Function analysis of rodent respiratory skeletal muscles, particularly the diaphragm, is commonly performed by isolating muscle strips using invasive surgical procedures. Although this is an effective method of assessing in vitro diaphragm activity, it involves non-survival surgery. The application of non-invasive ultrasound imaging as an in vivo procedure is beneficial since it not only reduces the number of animals sacrificed, but is also suitable for monitoring disease progression in live mice. Thus, our ultrasound imaging method may likely assist in the development of novel therapies that alleviate muscle injury induced by various respiratory diseases. Particularly, in clinical diagnoses of obstructive lung diseases, ultrasound imaging has the potential to be used in conjunction with other standard tests to detect the early onset of diaphragm muscle fatigue. In the current protocol, we describe how to accurately evaluate diaphragm contractility in a mouse model using a diagnostic ultrasound imaging technique.

A typical ultrasound image of a mouse diaphragm is shown in Figure&#160;1A. The mouse diaphragm maximal vertical displacement was recorded. This distance was calculated by precisely measuring the depth of diaphragm movement from relaxation to contraction using the electronic calipers that are part of the ultrasound software. Table 1 displays these distance measurements of diaphragmatic contractions from three different mice. After converting the cine loop file into a MPEG file, the respi...

Watch this Scientific Journal Video about Diagnostic Ultrasound Imaging of Mouse Diaphragm Function at JoVE.com

Diagnostic Ultrasound Imaging of Mouse Diaphragm Function

Diagnostic ultrasound imaging has proven to be effective in diagnosing various respiratory diseases in human and animal subjects. We demonstrate a comprehensive ultrasound protocol utilized by Dr. Zuo's lab to analyze diaphragm kinetics specifically in mouse models. This is also a non-invasive research technique which can provide quantitative information on mouse respiratory muscle function.

Function analysis of rodent respiratory skeletal muscles, particularly the diaphragm, is commonly performed by isolating muscle strips using invasive ...

diagnostic-ultrasound-imaging-of-mouse-diaphragm-function

Research

JoVE Journal

Medicine

15.9K Views.  The Ohio State University College of Medicine. Diagnostic ultrasound imaging has proven to be effective in diagnosing various respiratory diseases in human and animal subjects. We demonstrate a comprehensive ultrasound protocol utilized by Dr. Zuo's lab to analyze diaphragm kinetics specifically in mouse models. This is also a non-invasive research technique which can provide quantitative information on mouse respiratory muscle function.

Video: Diagnostic Ultrasound Imaging of Mouse Diaphragm Function

Murine Echocardiography and Ultrasound Imaging

Rodent models of cardiac pathophysiology represent a valuable research tool to investigate mechanism of disease as well as test new therapeutics.1 Echocardiography provides a powerful, non-invasive tool to serially assess cardiac morphometry and function in a living animal.2 However, using this technique on mice poses unique challenges owing to the small size and rapid heart rate of these animals.3 Until recently, few ultrasound systems were capable of performing quality echocardiography on mice, and those generally lacked the image resolution and frame rate necessary to obtain truly quantitative measurements. Newly released systems such as the VisualSonics Vevo2100 provide new tools for researchers to carefully and non-invasively investigate cardiac function in mice. This system generates high resolution images and provides analysis capabilities similar to those used with human patients. Although color Doppler has been available for over 30 years in humans, this valuable technology has only recently been possible in rodent ultrasound.4,5 Color Doppler has broad applications for echocardiography, including the ability to quickly assess flow directionality in vessels and through valves, and to rapidly identify valve regurgitation. Strain analysis is a critical advance that is utilized to quantitatively measure regional myocardial function.6 This technique has the potential to detect changes in pathology, or resolution of pathology, earlier than conventional techniques. Coupled with the addition of three-dimensional image reconstruction, volumetric assessment of whole-organs is possible, including visualization and assessment of cardiac and vascular structures. Murine-compatible contrast imaging can also allow for volumetric measurements and tissue perfusion assessment.

This video demonstrates use of a rail-mounted high-frequency ultrasound probe to perform echocardiography on an anesthetized mouse. The methods describe both conventional two-dimensional and M-mode measurements of cardiac function in addition to newer, more powerful tools such as color Doppler, strain analysis, as well as general and targeted contrast imaging.

Rodent models of cardiac pathophysiology represent a valuable research tool to investigate mechanism of disease as well as test new therapeutics.1  ...

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 ...

State of the Art Cranial Ultrasound Imaging in Neonates

Cranial ultrasound (CUS) is a reputable tool for brain imaging in critically ill neonates. It is safe, relatively cheap and easy to use, even when a patient is unstable. In addition it is radiation-free and allows serial imaging. CUS possibilities have steadily expanded. However, in many neonatal intensive care units, these possibilities are not optimally used. We present a comprehensive approach for neonatal CUS, focusing on optimal settings, different probes, multiple acoustic windows and Doppler techniques. This approach is suited for both routine clinical practice and research purposes. In a live demonstration, we show how this technique is performed in the neonatal intensive care unit. Using optimal settings and probes allows for better imaging quality and improves the diagnostic value of CUS in experienced hands. Traditionally, images are obtained through the anterior fontanel. Use of supplemental acoustic windows (lambdoid, mastoid, and lateral fontanels) improves detection of brain injury. Adding Doppler studies allows screening of patency of large intracranial arteries and veins. Flow velocities and indices can be obtained. Doppler CUS offers the possibility of detecting cerebral sinovenous thrombosis at an early stage, creating a window for therapeutic intervention prior to thrombosis-induced tissue damage. Equipment, data storage and safety aspects are also addressed.

Cranial ultrasound (CUS) is a valuable tool for brain imaging in critically ill neonates. This video shows a comprehensive approach for neonatal (Doppler) CUS for both clinical and research purposes, including a bedside demonstration of the technique.

Cranial ultrasound (CUS) is a reputable tool for brain imaging in critically ill neonates. It is safe, relatively cheap and easy to use, even when a ...

High-frequency Ultrasound Imaging of Mouse Cervical Lymph Nodes

High-frequency ultrasound (HFUS) is widely employed as a non-invasive method for imaging internal anatomic structures in experimental small animal systems. HFUS has the ability to detect structures as small as 30 &#181;m, a property that has been utilized for visualizing superficial lymph nodes in rodents in brightness (B)-mode. Combining power Doppler with B-mode imaging allows for measuring circulatory blood flow within lymph nodes and other organs. While HFUS has been utilized for lymph node imaging in a number of mouse&#160; model systems, a detailed protocol describing HFUS imaging and characterization of the cervical lymph nodes in mice has not been reported. Here, we show that HFUS can be adapted to detect and characterize cervical lymph nodes in mice. Combined B-mode and power Doppler imaging can be used to detect increases in blood flow in immunologically-enlarged cervical nodes. We also describe the use of B-mode imaging to conduct fine needle biopsies of cervical lymph nodes to retrieve lymph tissue for histological&#160; analysis. Finally, software-aided steps are described to calculate changes in lymph node volume and to visualize changes in lymph node morphology following image reconstruction. The ability to visually monitor changes in cervical lymph node biology over time provides a simple and powerful technique for the non-invasive monitoring of cervical lymph node alterations in preclinical mouse models of oral cavity disease.

This protocol describes the application of high-frequency ultrasound (HFUS) for imaging mouse cervical lymph nodes. This technique optimizes visualization and quantification of cervical lymph node morphology, volume and blood flow. Image-guided biopsy of cervical lymph nodes and processing of lymph tissue for histological evaluation is also demonstrated.

High-frequency ultrasound (HFUS) is widely employed as a non-invasive method for imaging internal anatomic structures in experimental small animal ...

Ultrasound Assessment of Endothelial Function: A Technical Guideline of the Flow-mediated Dilation Test

Cardiovascular disease is the primary cause of mortality and a major cause of disability worldwide. The dysfunction of the vascular endothelium is a pathological condition characterized mainly by a disruption in the balance between vasodilator and vasoconstrictor substances and is proposed to play an important role in the development of atherosclerotic cardiovascular disease. Therefore, a precise evaluation of endothelial function in humans represents an important tool that could help better understand the etiology of multiple cardio-centric pathologies.
Over the past twenty-five years, many methodological approaches have been developed to provide an assessment of endothelial function in humans. Introduced in 1989, the FMD test incorporates a forearm occlusion and subsequent reactive hyperemia that promotes nitric oxide production and vasodilation of the brachial artery. The FMD test is now the most widely utilized, non-invasive, ultrasonic assessment of endothelial function in humans and has been associated with future cardiovascular events.
Although the FMD test could have clinical utility, it is a physiological assessment that has inherited several confounding factors that need to be considered. This article describes a standardized protocol for determining FMD including the recommended methodology to help minimize the physiological and technical issues and improve the precision and reproducibility of the assessment.

The flow mediated dilation (FMD) test is the most commonly utilized, non-invasive, ultrasound assessment of endothelial function in humans. Although the FMD test has been related with the prediction of future cardiovascular disease and events, it is a physiological assessment with many inherent confounding factors that need to be considered.

Cardiovascular disease is the primary cause of mortality and a major cause of disability worldwide. The dysfunction of the vascular endothelium is a ...

Quantification of Levator Ani Hiatus Enlargement by Magnetic Resonance Imaging in Males and Females with Pelvic Organ Prolapse

Here we present a protocol to examine the levator ani hiatus in males and females with pelvic organ prolapse, during the Valsalva maneuver and while evacuating acoustic gel, using a horizontally oriented 1.5 T magnetic resonance (MR) scanner. On midsagittal images, the vertical distance of pelvic organs is measured in millimeters relative to the hymen plane (female) and to the lower border of the symphysis pubis (male), preceded by - (above) or + ( below) signs. On axial images, the levator ani area is calculated in square centimeters with a free-hand tracing method from three key images, passing through the midsymphysis (level I), tangential to the lower border of the symphysis (level II), and at the maximal anterior rectal wall bulging (level III). Areas at rest and strained are compared to find evidence of a percentage of increase. The purpose is to provide objective evidence of the maximal extent of pelvic organs descent and hiatus enlargement without the interference of foreign objects or the examiner&#39;s proximity, so as to overcome the limitations of pelvic examination and transperineal sonography (i.e., subjectivity and sex-related limitations [female only]).

Here we present a protocol to standardize the measurement of the levator ani hiatus size&#160;by magnetic resonance imaging. The purpose is to extract biomechanical inferences from image analysis by comparing resting and straining values in patients of both sexes with pelvic prolapse, using consistent anatomical bony landmarks.

Here we present a protocol to examine the levator ani hiatus in males and females with pelvic organ prolapse, during the Valsalva maneuver and while ...

Cardiac Magnetic Resonance for the Evaluation of Suspected Cardiac Thrombus: Conventional and Emerging Techniques

We present the conventional cardiac magnetic resonance (CMR) protocol for evaluating a suspected thrombus and highlight emerging techniques.&#160;The appearance of a mass on certain magnetic resonance (MR) sequences can help differentiate a thrombus from competing diagnoses such as a tumor. T1 and T2 signal characteristics of a thrombus are related to the evolution of hemoglobin properties. A thrombus typically does not enhance following contrast administration, which also helps differentiation from a tumor. We also highlight the emerging role of T1 mapping in the evaluation of a thrombus, which can add another level of support in diagnosis. Prior to any CMR exam, patient screening and interviews are critical to ensure safety and to optimize patient comfort. Effective communication during the exam between the technologist and the patient promotes proper breath holding technique and higher quality images. Volumetric post processing and structured reporting are helpful to ensure that the radiologist answers the ordering services&#39; question and communicates these results effectively. Optimal pre-MR safety evaluation, CMR exam execution, and post exam processing and reporting allow for delivery of high quality radiological service in the evaluation of a suspected cardiac thrombus.

The goal of this article is to describe how cardiac magnetic resonance can be used for the evaluation and diagnosis of a suspected cardiac thrombus. The method presented will describe data acquisition as well as the pre-procedure and post-procedure protocol.

We present the conventional cardiac magnetic resonance (CMR) protocol for evaluating a suspected thrombus and highlight emerging techniques.&#160;The ...

Near Infrared Photoimmunotherapy for Mouse Models of Pleural Dissemination

The efficacy of photoimmunotherapy can be evaluated more accurately with an orthotopic mouse model than with a subcutaneous one. A pleural dissemination model can be used for the evaluation of treatment methods for intrathoracic diseases such as lung cancer or malignant pleural mesothelioma.
Near-infrared photoimmunotherapy (NIR-PIT) is a recently developed cancer treatment strategy that combines the specificity of tumor-targeting antibodies with toxicity caused by a photoabsorber (IR700Dye) after exposure to NIR light. The efficacy of NIR-PIT has been reported using various antibodies; however, only a few reports have shown the therapeutic effect of this strategy in an orthotopic model. In the present study, we demonstrate an example of efficacy evaluation of the pleural disseminated lung cancer model, which was treated using NIR-PIT.

Near-infrared photoimmunotherapy (NIR-PIT) is an emerging cancer therapeutic strategy that utilizes an antibody-photoabsorber (IR700Dye) conjugate and NIR light to destroy cancer cells. Here, we present a method to evaluate the antitumor effect of NIR-PIT in a mouse model of pleural disseminated lung cancer and malignant pleural mesothelioma using bioluminescence imaging.

The efficacy of photoimmunotherapy can be evaluated more accurately with an orthotopic mouse model than with a subcutaneous one. A pleural dissemination ...

Interventional Diagnostic Procedure: A Practical Guide for the Assessment of Coronary Vascular Function

Approximately 40% of patients undergoing invasive coronary angiography for investigation of angina are found to have no obstructive coronary artery disease (ANOCA). Abnormal coronary function underlies coronary vasomotion syndromes including coronary endothelial dysfunction, microvascular angina, vasospastic angina, post-PCI angina and myocardial infarction with no obstructive coronary arteries (MINOCA). Each of these endotypes are distinct subgroups, characterized by specific disease mechanisms. Diagnostic criteria and linked therapy for these conditions are now established by expert consensus and clinical guidelines.
Coronary function tests are performed as an adjunctive interventional diagnostic procedure (IDP) in appropriately selected patients during coronary angiography. This aids differentiation of patients according to endotype. The IDP includes two distinct components: a diagnostic guidewire test and a pharmacological coronary reactivity test. The tests last approximately 5 minutes for the former and 10-15 minutes for the latter. Patient safety and staff education are key.
The diagnostic guidewire test measures parameters of coronary flow limitation (fractional flow reserve [FFR], coronary flow reserve [CFR], microvascular resistance [index of microvascular resistance (IMR)], basal resistance index, and vasodilator function [CFR, resistive reserve ratio (RRR)]).
The pharmacological coronary reactivity test measures the vasodilator potential and propensity to vasospasm of both the main coronary arteries and the micro-vessels. It involves intra-coronary infusion of acetylcholine and glyceryl trinitrate (GTN). Acetylcholine is not licensed for parenteral use and is therefore prescribed on a named-patient basis. Vasodilatation is the normal, expected response to infusion of physiological concentrations of acetylcholine. Vascular spasm represents an abnormal response, which supports the diagnosis of vasospastic angina.
The purpose of this practical guide is to provide information on the preparation and administration of the IDP in clinical practice. It discusses some key preparation and safety considerations, as well as tips for procedural success. The IDP supports stratified medicine for a personalized approach to health and wellbeing.

The purpose of this practical guide is to provide information on the preparation and administration of an interventional diagnostic procedure in clinical practice. It discusses some key preparation and safety considerations, as well as tips for procedural success.

Approximately 40% of patients undergoing invasive coronary angiography for investigation of angina are found to have no obstructive coronary artery ...

A Non-Invasive Method for Generating the Cyclic Loading-Induced Intra-Articular Cartilage Lesion Model of the Rat Knee

The pathophysiology of primary osteoarthritis (OA) remains unclear. However, a specific subclassification of OA in relatively younger age groups is likely correlated with a history of articular cartilage damage and ligament avulsion. Surgical animal models of OA of the knee play an important role in understanding the onset and progression of post-traumatic OA and aid in the development of novel therapies for this disease. However, non-surgical models have been recently considered to avoid traumatic inflammation that could affect the evaluation of the intervention. 
In this study, an intra-articular cartilage lesion rat model induced by in vivo cyclic compressive loading was developed, which allowed researchers to (1) determine the optimal magnitude, speed, and duration of load that could cause focal cartilage damage; (2) assess post-traumatic spatiotemporal pathological changes in chondrocyte vitality; and (3) evaluate the histological expression of destructive or protective molecules that are involved in the adaptation and repair mechanisms against joint compressive loads. This report describes the experimental protocol for this novel cartilage lesion in a rat model.

Here, we present the cyclic loading-induced intra-articular cartilage lesion model of the rat knee, generated by 60 cyclic compressions over 20 N, resulting in damage to the femoral condylar cartilage in rats.

The pathophysiology of primary osteoarthritis (OA) remains unclear. However, a specific subclassification of OA in relatively younger age groups is likely ...