The authors have no acknowledgements.

The protocol illustrated here follows the guidelines of the human research ethics committee at Brigham and Women&#39;s Hospital.
1. Preoperative Protocol
<ol>
	<li>Assess patients with spinal pathology in clinic and determine eligibility for spinal surgery. Perform neurological assessment and obtain CT or MRI scan to identify spinal lesion.</li>
	<li>Include patients who have an intradural pathology such as schwannoma, ependymoma, meningioma, astrocytoma, etc.; or patients who have a ventral compressive extradural pathology, such as a ventral thoracic herniated disc, fracture fragments ventrally, or a spinal bony tumor with ventral compression. 
	NOTE: Pathology is determined by spinal imaging with CT or MRI. Exclusion criteria includes the patients who cannot tolerate surgery, or patients with an extremely poor prognosis.</li>
</ol>
2. Preparation for Surgery
<ol>
	<li>Do not allow the patient to consume anything by mouth after the midnight before surgery. 
	NOTE: The patient will be placed under general anesthesia and intubated by the anesthesiologist.</li>
	<li>Position patient with their back exposed according to surgeon&#39;s preference for the spinal surgery.</li>
	<li>Sterilize the surgical area with povidone-iodine by scrubbing the area.</li>
</ol>
3. Surgery
Note: This section of the protocol follows general spine surgery techniques that can be referenced from any reputable spine surgery technique textbook19.
<ol>
	<li>Make an incision with a scalpel along the length of the spine over the appropriate vertebrae levels and continue to make a straight incision down until the bone is reached. 
	NOTE: The size of the incision will depend on the size of the pathology. For example, if the tumor spans two vertebral levels, then at least two vertebral levels will need to be exposed. When the bone is exposed, an X-ray with a portable X-ray machine can be performed to verify the correct vertebrae.</li>
	<li>Perform subperiosteal dissection by electrosurgical cautery and expose the spinous process which is visualized as a bulbous bony process. Turn the cutting edge ventrally and sweep across the laminar.</li>
	<li>Use a combination of a Leksell bone plier and a highspeed drill to remove the bony lamina and spinous process to expose the ligamentum flavum underneath.</li>
	<li>Use an angled Curette and Kerrison bone punch to remove the ligamentum flavum to reveal the dura mater underneath.</li>
	<li>Use bipolar and hemostatic matrix to achieve hemostasis. 
	NOTE: The success of a good ultrasound image relies upon a clean surgical field.</li>
</ol>
4. Intraoperative Ultrasound
<ol>
	<li>Use a mobile ultrasound machine and a transducer probe with a 20 mm diameter. 
	NOTE: The probe should have a 10 to 4.4 MHz frequency range. Any comparable device with similar probe diameter and frequency range should suffice.</li>
	<li>After the bony removal and dura exposure, fill the surgical field with sufficient saline solution such that the ultrasound transducer probe can be submerged. 
	NOTE: Generally, a range of 100-500 mL of saline solution is needed. The saline solution allows for acoustic coupling.</li>
	<li>Turn on the ultrasound machine and place the ultrasound probe within the saline bath at the level of interest to begin acquiring images. 
	NOTE: It is not necessary to place the probe directly touching the dura or spinal cord. Images are acquired on the ultrasound screen in real-time and can be interpreted immediately by the surgeon. Images on the screen can be captured at any time by pressing the Freeze button and can be saved by pressing the Save button.</li>
	<li>Acquire real time images in the longitudinal plane by placing the ultrasound probe in line with the direction of the spinal canal to visualize the spinal cord and the lesion similar to the sagittal images from the MRI.</li>
	<li>Acquire real time images in the transverse plane by placing the ultrasound probe perpendicular to the spinal canal to visualize the spinal cord and the lesion like the axial images from the MRI.</li>
	<li>Acquire real-time images to verify the location of lesions that cannot be directly visualized, to correlate with the preoperative CT or MRI images, to guide surgical tool placement, and/or to confirm the resolution of pathology. 
	NOTE: When needed, a small piece of sterile compressed sponge approximately 0.5 cm x 0.5 cm can be used as a hyperechoic surgical marker to be placed in the surgical field and help correlate the surgical location with the image location. This helps to locate the lesion during the surgery and also helps to identify the margin of the tumor.</li>
</ol>
5. Postoperative Follow-up
<ol>
	<li>After discharge, have the patient return to the clinic within one month for follow-up.</li>
	<li>Perform a neurological assessment and CT or MRI scans to confirm the resolution of the symptoms and pathology.</li>
</ol>

<ol>
	<li>Reid, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrasonic+visualization+of+a+cervical+cord+cystic+astrocytoma.">Ultrasonic visualization of a cervical cord cystic astrocytoma.</a> AJR. American Journal of Roentgenology. 131 (5), 907-908 (1978).</li><li>Dohrmann, G. J., Rubin, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intraoperative+ultrasound+imaging+of+the+spinal+cord:+syringomyelia,+cysts,+and+tumors--a+preliminary+report.">Intraoperative ultrasound imaging of the spinal cord: syringomyelia, cysts, and tumors--a preliminary report.</a> Surgical Neurology. 18 (6), 395-399 (1982).</li><li>Rubin, J. M., Dohrmann, G. 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A., 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=Ultrasound-guided+spinal+fracture+repositioning,+ligamentotaxis,+and+remodeling+after+thoracolumbar+burst+fractures.">Ultrasound-guided spinal fracture repositioning, ligamentotaxis, and remodeling after thoracolumbar burst fractures.</a> Spine. 31 (20), 739-747 (2006).</li><li>Nishimura, Y., Thani, N. B., Tochigi, S., Ahn, H., Ginsberg, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thoracic+discectomy+by+posterior+pedicle-sparing,+transfacet+approach+with+real-time+intraoperative+ultrasonography:+Clinical+article.">Thoracic discectomy by posterior pedicle-sparing, transfacet approach with real-time intraoperative ultrasonography: Clinical article.</a> Journal of Neurosurgery. Spine. 21 (4), 568-576 (2014).</li><li>Randel, S., Gooding, G. A., Dillon, W. 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The authors have nothing to disclose.

Intraoperative ultrasound in the spinal surgery has largely fallen out of favor with the advent of newer technology, however, it continues to provide several advantages over the other available imaging modalities such as MRI and CT6,9,16,17,18. In addition to being inexpensive, in this protocol we also show that it is simple to use and can provide visualizatio...

Ultrasound is one of the most common diagnostic tools in medicine, particularly for visualizing pathology in the abdomen, limbs, and neck. However, its use to investigate cranial and spinal lesions is not currently widely utilized. In 1978, Reid was the first to report the use of ultrasound to visualize cervical cord cystic astrocytoma1. Here, scans were performed with the patient&#39;s neck flexed to allow opening of the intralaminar window. Four years later, in 1982, Dohrmann and Rubin reported the use of ultrasound intraoperatively to visualize the intradural space in 10 patients2. Pathologies identified with intraoperative ultrasound among the 10 patients included syringomyelia, spinal cord cysts, and intramedullary and extramedullary tumors. They further demonstrated the use of intraoperative ultrasound to guide catheters and probes for biopsy of tumors, drainage of cysts, and ventricular shunt catheter placement3. This allowed the real-time monitoring and precise positioning of probes/catheters, reducing inaccuracy and errors in placement. Following these initial reports, several others have published the use of intraoperative ultrasound for guiding spinal cord cyst drainage, intramedullary and extramedullary tumor resection, and syringo-subarachnoid shunt catheter placement4,5,6,7,8,9,10. Additionally, it has been shown to also increase rate of complete resection of intra-axial solid brain tumors and spinal intradural tumors11,12. Intraoperative ultrasound has also proven to be useful for the intraoperative surgical planning before manipulation of the tissue and subsequent visualization of adequate neural element decompression in patients with spine fractures7,9,13,14,15.
With the advent of newer intraoperative technology allowing clearer visualization of soft tissues, such as magnetic resonance imaging (MRI) and computed tomography (CT), intraoperative ultrasound has become less common and a less favored intraoperative imaging modality among neurosurgeons today16. However, intraoperative ultrasound can have advantages over these newer technologies in certain operative cases (Table 1). Intraoperative ultrasound has shown to demonstrate better soft tissue visualization of intradural structures when compared with intraoperative CT (iCT) or cone-beam CT (cbCT)9,17. While intraoperative MRI (iMRI) is useful where available because of the higher soft tissue resolution it provides, it is costly, time consuming and does not provide real-time images6, 16,18. An example is in the circumstance of an intradural mass ventral to the thecal sac that the surgeon is unable to directly visualize. Additionally, despite being operator dependent, from our experience, intraoperative ultrasound is fairly simple to use and can be easily read without a radiologist.

<table border="0" cellpadding="0" cellspacing="0" style="width:848px;" width="847">
	<tbody>
		<tr height="40">
			<td height="40" style="height:40px;width:215px;">Aloka Prosound 5 mobile ultrasound machine</td>
			<td style="width:123px;">Hitachi</td>
			<td style="width:344px;">N/A</td>
			<td style="width:167px;">any comparable devices on the market should suffice</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">UST-9120 transducer probe.</td>
			<td>Hitachi</td>
			<td>UST-9120</td>
			<td>Has a 20mm diameter with 10 to 4.4 MHz frequency range (any comparable compatible transducer should suffice).</td>
		</tr>
	</tbody>
</table>

intraoperative ultrasound in spinal surgery

Since the 1980s, there have been several reports for the use of intraoperative ultrasound as a useful adjunct in spinal surgery. However, with the advent of newer cutting-edge imaging modalities, the use of intraoperative ultrasound in spine surgery has largely fallen out of favor. Despite this, intraoperative ultrasound continues to provide several advantages over other intraoperative techniques such as magnetic resonance imaging and computed tomography including being more cost-effective, efficient, and easy to operate and interpret. Additionally, it remains the only method for the real-time visualization of soft tissue and pathologies. This paper focuses on the advantages of using intraoperative ultrasound, especially in cases of intradural lesions and lesions ventral to the thecal sac when approaching posteriorly.

On normal spine ultrasound imaging, the dura is an echogenic layer that surrounds the anechoic spinal fluid. The spinal cord is distinguished by its homogenous appearance and low echogenicity which is surrounded by an echogenic rim. This echogenic rim is due to the density shift from the spinal fluid to the spinal cord. The central canal appears as a bright central echo, while exiting nerve roots appear highly echogenic, particularly at the cauda equina16. Intraope...

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Intraoperative Ultrasound in Spinal Surgery

Here, we present a protocol on the use of intraoperative ultrasound in spinal surgery, particularly in cases of intradural lesions and lesions in the ventral spinal canal when using a posterior approach.

Since the 1980s, there have been several reports for the use of intraoperative ultrasound as a useful adjunct in spinal surgery. However, with the advent ...

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4.5K Views.  Harvard Medical School. Here, we present a protocol on the use of intraoperative ultrasound in spinal surgery, particularly in cases of intradural lesions and lesions in the ventral spinal canal when using a posterior approach.

Video: Intraoperative Ultrasound in Spinal Surgery

Acute and Chronic Tactile Sensory Testing after Spinal Cord Injury in Rats

Spinal cord injury (SCI) impairs sensory systems causing allodynia1-8. To identify cellular and molecular causes of allodynia, sensitive and valid sensory testing in rat SCI models is needed. However, until recently, no single testing approach had been validated for SCI so that standardized methods have not been implemented across labs. Additionally, available testing methods could not be implemented acutely or when severe motor impairments existed, preventing studies of the development of SCI-induced allodynia3. Here we present two validated sensory testing methods using von Frey Hair (VFH) monofilaments which quantify changes in tactile sensory thresholds after SCI4-5. One test is the well-established Up-Down test which demonstrates high sensitivity and specificity across different SCI severities when tested chronically5. The other test is a newly-developed dorsal VFH test that can be applied acutely after SCI when allodynia develops, prior to motor recovery4-5. Each VFH monofilament applies a calibrated force when touched to the skin of the hind paw until it bends. In the up-down method, alternating VFHs of higher or lower forces are used on the plantar L5 dermatome to delineate flexor withdrawal thresholds. Successively higher forces are applied until withdrawal occurs then lower force VFHs are used until withdrawal ceases. The tactile threshold reflects the force required to elicit withdrawal in 50% of the stimuli. For the new test, each VFH is applied to the dorsal L5 dermatome of the paw while the rat is supported by the examiner. The VFH stimulation occurs in ascending order of force until at least 2 of 3 applications at a given force produces paw withdrawal. Tactile sensory threshold is the lowest force to elicit withdrawal 66% of the time. Acclimation, testing and scoring procedures are described. Aberrant trials that require a retest and typical trials are defined. Animal use was approved by Ohio State University Animal Care and Use Committee.

We describe two tactile sensory testing methods for acute or chronic periods of spinal cord injury in rats. These validated procedures can detect the development and maintenance of allodynia-like sensations.

Spinal cord injury (SCI) impairs sensory systems causing allodynia1-8. To identify cellular and molecular causes of allodynia, sensitive and valid sensory ...

Controlled Cortical Impact Model for Traumatic Brain Injury

Every year over a million Americans suffer a traumatic brain injury (TBI). Combined with the incidence of TBIs worldwide, the physical, emotional, social, and economical effects are staggering. Therefore, further research into the effects of TBI and effective treatments is necessary. The controlled cortical impact (CCI) model induces traumatic brain injuries ranging from mild to severe. This method uses a rigid impactor to deliver mechanical energy to an intact dura exposed following a craniectomy. Impact is made under precise parameters at a set velocity to achieve a pre-determined deformation depth. Although other TBI models, such as weight drop and fluid percussion, exist, CCI is more accurate, easier to control, and most importantly, produces traumatic brain injuries similar to those seen in humans. However, no TBI model is currently able to reproduce pathological changes identical to those seen in human patients. The CCI model allows investigation into the short-term and long-term effects of TBI, such as neuronal death, memory deficits, and cerebral edema, as well as potential therapeutic treatments for TBI.

Traumatic brain injuries (TBIs) remain a serious health problem. Using the controlled cortical impact surgery model, research on the effects of TBI and possible treatment methods may be performed.

Every year over a million Americans suffer a traumatic brain injury (TBI).  Combined with the incidence of TBIs worldwide, the physical, emotional, ...

Ultrasound Assessment of Endothelial-Dependent Flow-Mediated Vasodilation of the Brachial Artery in Clinical Research

The vascular endothelium is a monolayer of cells that cover the interior of blood vessels and provide both structural and functional roles. The endothelium acts as a barrier, preventing leukocyte adhesion and aggregation, as well as controlling permeability to plasma components. Functionally, the endothelium affects vessel tone.
Endothelial dysfunction is an imbalance between the chemical species which regulate vessel tone, thombroresistance, cellular proliferation and mitosis. It is the first step in atherosclerosis and is associated with coronary artery disease, peripheral artery disease, heart failure, hypertension, and hyperlipidemia.
The first demonstration of endothelial dysfunction involved direct infusion of acetylcholine and quantitative coronary angiography. Acetylcholine binds to muscarinic receptors on the endothelial cell surface, leading to an increase of intracellular calcium and increased nitric oxide (NO) production. In subjects with an intact endothelium, vasodilation was observed while subjects with endothelial damage experienced paradoxical vasoconstriction.
There exists a non-invasive, in vivo method for measuring endothelial function in peripheral arteries using high-resolution B-mode ultrasound. The endothelial function of peripheral arteries is closely related to coronary artery function. This technique measures the percent diameter change in the brachial artery during a period of reactive hyperemia following limb ischemia.
This technique, known as endothelium-dependent, flow-mediated vasodilation (FMD) has value in clinical research settings. However, a number of physiological and technical issues can affect the accuracy of the results and appropriate guidelines for the technique have been published. Despite the guidelines, FMD remains heavily operator dependent and presents a steep learning curve. This article presents a standardized method for measuring FMD in the brachial artery on the upper arm and offers suggestions to reduce intra-operator variability.

Endothelial dysfunction is associated with numerous disease states and is predictive of adverse cardiovascular events in humans. Flow-mediated vasodilation (FMD) is a non-invasive ultrasound method of evaluating endothelial function. Methodological choices and operator experience may affect results. A systematic approach to FMD in human studies is discussed here.

The vascular endothelium is a monolayer of cells that cover the interior of blood vessels and provide both structural and functional roles. The ...

Contrast Enhanced Ultrasound Imaging for Assessment of Spinal Cord Blood Flow in Experimental Spinal Cord Injury

Reduced spinal cord blood flow (SCBF) (i.e., ischemia) plays a key role in traumatic spinal cord injury (SCI) pathophysiology and is accordingly an important target for neuroprotective therapies. Although several techniques have been described to assess SCBF, they all have significant limitations. To overcome the latter, we propose the use of real-time contrast enhanced ultrasound imaging (CEU). Here we describe the application of this technique in a rat contusion model of SCI. A jugular catheter is first implanted for the repeated injection of contrast agent, a sodium chloride solution of sulphur hexafluoride encapsulated microbubbles. The spine is then stabilized with a custom-made 3D-frame and the spinal cord dura mater is exposed by a laminectomy at ThIX-ThXII. The ultrasound probe is then positioned at the posterior aspect of the dura mater (coated with ultrasound gel). To assess baseline SCBF, a single intravenous injection (400 &#181;l) of contrast agent is applied to record its passage through the intact spinal cord microvasculature. A weight-drop device is subsequently used to generate a reproducible experimental contusion model of SCI. Contrast agent is re-injected 15 min following the injury to assess post-SCI SCBF changes. CEU allows for real time and in-vivo assessment of SCBF changes following SCI. In the uninjured animal, ultrasound imaging showed uneven blood flow along the intact spinal cord. Furthermore, 15 min post-SCI, there was critical ischemia at the level of the epicenter while SCBF remained preserved in the more remote intact areas. In the regions adjacent to the epicenter (both rostral and caudal), SCBF was significantly reduced. This corresponds to the previously described &#8220;ischemic penumbra zone&#8221;. This tool is of major interest for assessing the effects of therapies aimed at limiting ischemia and the resulting tissue necrosis subsequent to SCI.

Contrast Enhanced Ultrasound imaging is a reliable in-vivo tool for quantifying spinal cord blood flow in an experimental rat spinal cord injury model. This paper contains a comprehensive protocol for application of this technique in association with a contusion model of thoracic spinal cord injury.

Reduced spinal cord blood flow (SCBF) (i.e., ischemia) plays a key role in traumatic spinal cord injury (SCI) pathophysiology and is accordingly an ...

Intraoperative Gastroscopy for Tumor Localization in Laparoscopic Surgery for Gastric Adenocarcinoma

Determining resection margins for gastric cancer, which are not exposed to the serosal surface of the stomach, is the most important procedure during totally laparoscopic gastrectomy (TLG). The aim of this protocol is to introduce a procedure for intraoperative gastroscopy, in order to directly mark tumors during TLG for gastric cancer in the middle third of the stomach. Patients who were diagnosed with adenocarcinoma in the middle third of the stomach were enrolled in this case series. Before surgery, additional gastroscopy for tumor localization is not performed. Under general anesthesia, laparoscopic mobilization of the stomach is performed first. After the first portion of the duodenum is mobilized from the pancreas and clamped, the surgeon moves to the other side for the gastroscopic procedure. On the insertion of a gastroscope through the oral cavity into the stomach, 2 - 3 cc of indigo carmine is administered via an endoscopic injector into the gastric muscle layer at the proximal margin of the stomach. The location of stained serosa in the laparoscopic view is used to guide distal subtotal gastrectomy, however, total gastrectomy is performed if the tumor is too close to the esophagogastric junction. A specimen is sampled after distal gastrectomy to confirm sufficient length from resection margin to tumor before reconstruction. In our case series, all patients had tumor-free margins and required no additional resection. There was no morbidity related to the gastroscopic procedure, and the time required for the procedure has gradually decreased to about five minutes. Intraoperative gastroscopy for tumor localization is an accurate and tolerated method for gastric cancer patients undergoing totally laparoscopic distal gastrectomy.

In early gastric cancer, the aim of surgery is to precisely remove the distal stomach including the primary tumor. To do this, accurate localization of the tumor is crucial, especially in totally laparoscopic surgery. This protocol describes a procedure for intraoperative gastroscopy in totally laparoscopic subtotal gastrectomy.

Determining resection margins for gastric cancer, which are not exposed to the serosal surface of the stomach, is the most important procedure during ...

Cone Beam Intraoperative Computed Tomography-based Image Guidance for Minimally Invasive Transforaminal Interbody Fusion

Transforaminal lumbar interbody fusion (TLIF) is commonly used for the treatment of spinal stenosis, degenerative disc disease, and spondylolisthesis. Minimally invasive surgery (MIS) approaches have been applied to this technique with an associated decrease in estimated blood loss (EBL), length of hospital stay, and infection rates, while preserving outcomes with traditional open surgery. Previous MIS TLIF techniques involve significant fluoroscopy that subjects the patient, surgeon, and operating room staff to non-trivial levels of radiation exposure, particularly for complex multi-level procedures. We present a technique that utilizes an intraoperative computed tomography (CT) scan to aid in placement of pedicle screws, followed by traditional fluoroscopy for confirmation of cage placement. Patients are positioned in the standard fashion and a reference arc is placed in the posterior superior iliac spine (PSIS) followed by intraoperative CT scan. This allows for image-guidance-based placement of pedicle screws through a one-inch skin incision on each side. Unlike traditional MIS-TLIF that requires significant fluoroscopic imaging during this stage, the operation can now be performed without any additional radiation exposure to the patient or operating room staff. After completion of the facetectomy and discectomy, final TLIF cage placement is confirmed with fluoroscopy. This technique has the potential to decrease operative time and minimize total radiation exposure.

The purpose of this article is to provide image-guidance for minimally invasive transforaminal interbody fusion.

Transforaminal lumbar interbody fusion (TLIF) is commonly used for the treatment of spinal stenosis, degenerative disc disease, and spondylolisthesis. ...

Intraoperative Assessment of Resection Margins in Oral Cavity Cancer: This is the Way

The goal of head and neck oncological surgery is complete tumor resection with adequate resection margins while preserving acceptable function and appearance. For oral cavity squamous cell carcinoma (OCSCC), different studies showed that only 15%-26% of all resections are adequate. A major reason for the low number of adequate resections is the lack of information during surgery; the margin status is only available after the final histopathologic assessment, days after surgery.
The surgeons and pathologists at the Erasmus MC University Medical Center in Rotterdam started the implementation of specimen-driven intraoperative assessment of resection margins (IOARM) in 2013, which became the standard of care in 2015. This method enables the surgeon to turn an inadequate resection into an adequate resection by performing an additional resection during the initial surgery. Intraoperative assessment is supported by a relocation method procedure that allows accurate identification of inadequate margins (found on the specimen) in the wound bed.
The implementation of this protocol resulted in an improvement of adequate resections from 15%-40%. However, the specimen-driven IOARM is not widely adopted because grossing fresh tissue is counter-intuitive for pathologists. The fear exists that grossing fresh tissue will deteriorate the anatomical orientation, shape, and size of the specimen and therefore will affect the final histopathologic assessment. These possible negative effects are countered by the described protocol. Here, the protocol for specimen-driven IOARM is presented in detail, as performed at the institute.

The goal of this protocol is to provide a clear overview of specimen-driven intraoperative assessment of resection margins. It is encouraged to implement this protocol to improve patient care at other institutes.

The goal of head and neck oncological surgery is complete tumor resection with adequate resection margins while preserving acceptable function and ...

Endoscopic Ultrasound-Guided Biliary Drainage: Endoscopic Ultrasound-Guided Hepaticogastrostomy in Malignant Biliary Obstruction

Patients with unresectable malignant biliary obstruction often require biliary drainage to decompress the biliary system. Endoscopic Retrograde Cholangiopancreatography (ERCP) is the primary biliary drainage method whenever possible. Percutaneous Transhepatic Biliary Drainage (PTBD) is used as a salvage method if ERCP fails. Endoscopic Ultrasound-Guided Biliary Drainage (EUS-BD) provides a feasible alternative biliary drainage method where one of the methods is EUS guided Hepaticogastrostomy (EUS-HGS). Here we describe the EUS-HGS technique in a case of unresectable malignant hilar biliary obstruction to achieve biliary drainage.
Presented here is the case of a 71-year-old female with painless jaundice and weight loss for 2 weeks. Computed Tomography (CT) imaging showed a 4 x 5 cm hilar tumor with lymphadenopathy and liver metastasis. EUS fine needle biopsy (FNB) of the lesion was consistent with cholangiocarcinoma. Her bilirubin levels were 212 &#181;mol/L (&lt;15) during presentation.
A linear echoendoscope was used to locate the left dilated intrahepatic ducts (IHD) of the liver. The segment 3 dilated IHD was identified and punctured using a 19 G needle. Contrast was used to opacify the IHDs under fluoroscopic guidance. The IHD was cannulated using a 0.025-inch guidewire. This was followed by the dilation of the fistula tract using a 6 Fr electrocautery dilator along with a 4 mm biliary balloon dilator. A partially covered metallic stent of 10 cm in length was deployed under fluoroscopic guidance. The distal part opens in the IHD and the proximal part was deployed within the working channel of the echoendoscope that subsequently released into the stomach. The patient was discharged three days after the procedure. Follow up performed in the second and fourth weeks showed that the bilirubin levels were 30 &#181;mol/L and 14 &#181;mol/L, respectively. This indicates that EUS-HGS is a safe method for biliary drainage in unresectable malignant biliary obstruction.

Endoscopic Ultrasound-Guided Biliary Drainage (EUS-BD) is an alternative method of biliary decompression in malignant biliary obstruction. Here we describe the technique of EUS guided-Hepaticogastrostomy (EUS-HGS) in a case of unresectable malignant hilar biliary obstruction.

Patients with unresectable malignant biliary obstruction often require biliary drainage to decompress the biliary system. Endoscopic Retrograde ...

Orthopedic Robot-Assisted Femoral Neck System in the Treatment of Femoral Neck Fracture

Cannulated screw fixation is the main therapy for femoral neck fractures, especially in young patients. The traditional surgical procedure uses C-arm fluoroscopy to place the screw freehand and requires several guide wire adjustments, which increases the operation time and radiation exposure. Repeated drilling can also cause damage to the blood supply and bone quality of the femoral neck, which can be followed by complications such as screw loosening, nonunion, and femoral head necrosis. In order to make fixation more precise and reduce the incidence of complications, our team applied robot-assisted orthopedic surgery for screw placement using the femoral neck system to modify the traditional procedure. This protocol introduces how to import a patient's X-ray information into the system, how to perform screw path planning in software, and how the robotic arm assists in screw placement. Using this method, the surgeons can place the screw successfully the first time, improve the accuracy of the procedure, and avoid radiation exposure. The whole protocol includes the diagnosis of femoral neck fracture; the collection of intraoperative X-ray images; screw path planning in the software; precise placement of the screw under the assistance of the robotic arm by the surgeon; and verification of the implant placement.

This article introduces a method of robot-assisted orthopedic surgery for screw placement during the treatment of femoral neck fracture using the femoral neck system, which allows for more accurate screw placement, improved surgical efficiency, and fewer complications.

Cannulated screw fixation is the main therapy for femoral neck fractures, especially in young patients. The traditional surgical procedure uses C-arm ...

Point-of-Care Lung Ultrasound in Adults: Image Acquisition

Consultative ultrasound performed by radiologists has traditionally not been used for imaging the lungs, as the lungs&#39; air-filled nature normally prevents direct visualization of the lung parenchyma. When showing the lung parenchyma, ultrasound typically generates a number of non-anatomic artifacts. However, over the past several decades, these artifacts have been studied by diagnostic point-of-care ultrasound (POCUS) practitioners, who have identified findings that have value in narrowing the differential diagnoses of cardiopulmonary dysfunction. For instance, in patients presenting with dyspnea, lung POCUS is superior to chest radiography (CXR) for the diagnosis of pneumothorax, pulmonary edema, lung consolidations, and pleural effusions. Despite its known diagnostic value, the utilization of lung POCUS in clinical medicine remains variable, in part because training in this modality across hospitals remains inconsistent. To address this educational gap, this narrative review describes lung POCUS image acquisition in adults, including patient positioning, transducer selection, probe placement, acquisition sequence, and image optimization.

Point-of-care ultrasound (POCUS) of the lungs provides quick answers in rapidly changing clinical scenarios. We present an efficient and informative protocol for image acquisition for use in acute care settings.

Consultative ultrasound performed by radiologists has traditionally not been used for imaging the lungs, as the lungs&#39; air-filled nature normally ...