The recording of the surgical procedure and the use of its content for scientific and educational reasons were explained to the patient; he then signed a consent form, according to the Institution&#39;s human ethics committee. Written informed consent for the surgical and anesthetic procedures was also obtained.
NOTE: Patients with a confirmed diagnosis of achalasia by manometry and barium esophagram findings can be included in the protocol for robotic myotomy and partial fundoplication. A preoperative pre-anesthesia evaluation was performed, and patients with increased surgical risk were excluded. Patients who failed to meet the diagnostic criteria of achalasia and/or presented other esophageal motility disorders were excluded. Failure to sign both anesthetic and surgical forms also implied exclusion.
1. Operative setting and trocar placement
<ol>
	<li>Once under general anesthesia, place the patient in a supine position.</li>
	<li>Create a pneumoperitoneum using a Veress needle. Insert the needle above the umbilical scar.</li>
	<li>Use four 8 mm robotic trocars, one 12 mm trocar and one 5 mm trocar in this procedure. Place the 12 mm trocar in the supraumbilical area, left to the midline, for the robotic camera system. This positioning allows better visualization of the gastroesophageal junction (GEJ).</li>
	<li>Place the remaining trocars along a straight line above the umbilicus: two 8 mm trocars, one at the left and one at the right midclavicular line subcostal margin, and the remaining two trocars at the left and right lateral abdominal walls (Figure 4). A 5 mm trocar is placed in a subxiphoid position and then replaced by a Nathanson liver retractor.</li>
</ol>
2. Dissection of the lower esophagus and division of the short gastric vessels
<ol>
	<li>Place a Nathanson liver retractor in a subxiphoid position in order to elevate the left lobe of the liver.</li>
	<li>Start the operation by dividing the short gastric vessels, starting from the middle of the great curvature of the stomach all the way to the angle of His.</li>
	<li>Perform full mobilization of the gastric fundus, using an ultrasonic harmonic scalpel to free it from the retroperitoneum while an atraumatic grasper retracts the stomach.</li>
	<li>Divide the gastrohepatic ligament - below the hepatic branch of the vagus - and progressively dissect it in order to identify and expose both diaphragmatic crura.</li>
	<li>Place tape around the esophagus, allowing gentle traction.</li>
	<li>Proceed with the isolation of the esophagus by separating it from the left and right crura by blunt dissection. During the dissection, identify and preserve the posterior and anterior vagal trunks and both pleurae. The anterior vagal trunk is adhered to or embedded in the esophageal wall, and the posterior trunk lies on a layer of adipose tissue posterior to the esophagus.</li>
	<li>Mobilize the esophagus circumferentially, creating a longer intra-abdominal esophagus.</li>
</ol>
3. Heller myotomy
<ol>
	<li>Remove the fat pad by holding the adipose tissue that lies above the pharyngoesophageal ligament and separate it circumferentially from the esophagus wall with a harmonic scalpel in order to expose and better visualize the gastroesophageal junction.</li>
	<li>Before performing the myotomy, mark the esophageal wall with the bipolar forceps in the anterior midline of the esophagus, with an extension approximately 6 cm above the gastroesophageal junction.</li>
	<li>Grasp the borders of the myotomy and disrupt the muscular layer while moving the borders away from each other until exposure of the submucosal layer.</li>
	<li>Proceed with the myotomy with the harmonic scalpel by interposing the inactive jaw of the scalpel between the submucosal (pinkish) and muscular layers (whitish) and activating the trigger in order to cut and cauterize.</li>
	<li>During this dissection, make sure to separate the muscle edges of the myotomy laterally, thus avoiding it to fuse when healing. Use a sterile measuring stripe to ensure the length of the myotomy is 6 cm above the gastroesophageal junction and 3 cm below it.</li>
	<li>Continue the demarcation and myotomy below the gastroesophageal junction laterally into the stomach as the muscle fibers change direction from circular to oblique. Adequate extension of myotomy is crucial to achieve good postoperative results and avoid the recurrence of dysphagia.</li>
</ol>
4. Creation of the partial fundoplication
<ol>
	<li>Perform the repair of the hiatus with the figure of eight stitches, with 2.0 cotton sutures, although silk or polyester sutures may also be suitable options. Be aware not to tighten the hiatus, which may lead to postoperative dysphagia.</li>
	<li>Proceed with the Heller Pinotti fundoplication. That technique involves creating an anterior-lateral-posterior fundoplication using three suture lines to connect the gastric fundus and esophagus.</li>
	<li>Mobilize the gastric fundus and bring it around the back of the esophagus in order to perform the suturing of the gastric fundus to the posterior wall of the distal esophagus.</li>
	<li>Perform interrupted stitches with 2-0 cotton sutures, and attach the seromuscular layer of the stomach to the muscular layer of the esophagus. The extension of the suture should correspond to that of the myotomy; usually 2-3 stitches are enough. The first stitch of that row should also incorporate the hiatus. Although this maneuver does not prevent the migration of the valve, it restrains its rotation.</li>
	<li>Resect a muscular strip over the gastroesophageal junction, when needed.</li>
	<li>Next, perform the second row of sutures from the gastric fundus to the left edge of the myotomy. As with the first row, the initial stitch should also be attached to the hiatus.</li>
	<li>Perform the third and last row of sutures from the gastric fundus to the right edge of the myotomy. By the end of these steps, the exposed submucosa of the esophagus should be covered by gastric serosa.</li>
</ol>

<ol>
	<li>Moonen, A., Boeckxstaens, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Current+diagnosis+and+management+of+achalasia.">Current diagnosis and management of achalasia.</a> Journal of Clinical Gastroenterology. 48 (6), 484-490 (2014).</li><li>Tuason, J., Inoue, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Current+status+of+achalasia+management:+a+review+on+diagnosis+and+treatment.">Current status of achalasia management: a review on diagnosis and treatment.</a> Journal of Gastroenterology. 52 (4), 401-406 (2017).</li><li>Pasricha, P. J., Rai, R., Ravich, W. J., Hendrix, T. R., Kalloo, A. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Botulinum+toxin+for+achalasia:+long-term+outcome+and+predictors+of+response.">Botulinum toxin for achalasia: long-term outcome and predictors of response.</a> Gastroenterology. 110 (5), 1410-1415 (1996).</li><li>Eckardt, V., Gockel, I., Bernhard, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pneumatic+dilation+for+achalasia:+late+results+of+a+prospective+follow+up+investigation.">Pneumatic dilation for achalasia: late results of a prospective follow up investigation.</a> Gut. 53 (5), 629-633 (2004).</li><li>Inoue, H., 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=Peroral+endoscopic+myotomy+(POEM)+for+esophageal+achalasia.">Peroral endoscopic myotomy (POEM) for esophageal achalasia.</a> Endoscopy. 42 (4), 265-271 (2010).</li><li>Doubova, M., 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=Long-term+symptom+control+after+laparoscopic+heller+myotomy+and+dor+fundoplication+for+achalasia.">Long-term symptom control after laparoscopic heller myotomy and dor fundoplication for achalasia.</a> Annals in Thoracic Surgery. 111 (5), 1717-1723 (2021).</li><li>Vaezi, M. F., Pandolfino, J. E., Yadlapati, R. H., Greer, K. B., Kavitt, R. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ACG+clinical+guidelines:+Diagnosis+and+management+of+achalasia.">ACG clinical guidelines: Diagnosis and management of achalasia.</a> American Journal of Gastroenterology. 115 (9), 1393-1411 (2020).</li><li>Triadafilopoulos, G., 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=The+Kagoshima+consensus+on+esophageal+achalasia.">The Kagoshima consensus on esophageal achalasia.</a> Diseases of Esophagus. 25 (4), 337-348 (2012).</li><li>Richards, W. O., 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=Heller+myotomy+versus+Heller+myotomy+with+Dor+fundoplication+for+achalasia:+A+prospective+randomized+double-blind+clinical+trial.">Heller myotomy versus Heller myotomy with Dor fundoplication for achalasia: A prospective randomized double-blind clinical trial.</a> Annals of Surgery. 240 (3), 405-415 (2004).</li><li>Wang, X. H., Tan, Y. Y., Zhu, H. Y., Li, C. J., Liu, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Full-thickness+myotomy+is+associated+with+a+higher+rate+of+postoperative+gastroesophageal+reflux+disease.">Full-thickness myotomy is associated with a higher rate of postoperative gastroesophageal reflux disease.</a> World Journal of Gastroenterology. 22 (42), 9419-9426 (2016).</li><li>Ali, A., Pellegrini, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laparoscopic+myotomy:+technique+and+efficacy+in+treating+achalasia.">Laparoscopic myotomy: technique and efficacy in treating achalasia.</a> Gastrointestinal Endoscopy Clinics of North America. 11 (2), 347-358 (2001).</li><li>Spiess, A. E., Kahrilas, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Treating+achalasia:+from+whalebone+to+laparoscope.">Treating achalasia: from whalebone to laparoscope.</a> JAMA. 280 (7), 638-642 (1998).</li><li>Xie, J., Vatsan, M. S., Gangemi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laparoscopic+versus+robotic-assisted+Heller+myotomy+for+the+treatment+of+achalasia:+A+systematic+review+with+meta-analysis.">Laparoscopic versus robotic-assisted Heller myotomy for the treatment of achalasia: A systematic review with meta-analysis.</a> International Journal of Medical Robotics and Computer Assisted Surgery. 17 (4), e2253 (2021).</li><li>Kim, S. S., Guillen-Rodriguez, J., Little, A. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimal+surgical+intervention+for+achalasia:+laparoscopic+or+robotic+approach.">Optimal surgical intervention for achalasia: laparoscopic or robotic approach.</a> Journal of Robotic Surgery. 13 (3), 397-400 (2019).</li><li>Pallabazzer, G., 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=Clinical+and+pathophysiological+outcomes+of+the+robotic-assisted+Heller-Dor+myotomy+for+achalasia:+a+single-center+experience.">Clinical and pathophysiological outcomes of the robotic-assisted Heller-Dor myotomy for achalasia: a single-center experience.</a> Journal of Robotic Surgery. 14 (2), 331-335 (2020).</li><li>Baek, S. J., Kim, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Robotics+in+general+surgery:+an+evidence-based+review.">Robotics in general surgery: an evidence-based review.</a> Asian Journal of Endoscopic Surgery. 7 (2), 117-123 (2014).</li><li>Bianchi, E. T., 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=Heller-Pinotti,+a+modified+partial+fundoplication+associated+with+myotomy+to+treat+achalasia:+technical+and+final+results+from+445+patients.">Heller-Pinotti, a modified partial fundoplication associated with myotomy to treat achalasia: technical and final results from 445 patients.</a> Mini-invasive Surgery. 1, 153-159 (2017).</li></ol>

There are no disclosures.

This protocol describes robotic myotomy and partial fundoplication as a treatment for achalasia. The article highlights a Heller Pinotti fundoplication, which consists of a variation of the classic Dor fundoplication. This technique, presented in the article, demonstrates the performance of three rows of sutures, instead of the classic two sutures performed in the Dor fundoplication. The optimal type of fundoplication, including total, anterior, or posterior has been extensively studied in the literature, but there is still controversy surrounding the best approach for improving outcomes17. Modifications have been implemented to the technique over time, for example, the introduction of a posterior suture line to the classic Dor fundoplication, resulting in a postero-lateral-anterior fundoplication that provides enhanced reflux control compared to the anterior fundoplication alone. This technique, widely known as the Heller Pinotti procedure, has gained popularity in Brazil17.
Critical steps during the procedure include the proper placement of the robotic arms and trocars and careful dissection of the muscular layers of the esophagus. While laparoscopic Heller myotomy is currently considered the gold standard treatment for achalasia, robotic-assisted myotomy can also be a successful alternative in the hands of experienced surgeons. 
Possible reasons for the low rate of robotic-assisted operations for Heller myotomy and other gastro-esophageal procedures have already been presented by several authors16 those include, mostly, a longer learning curve and cost. Although the robotic myotomy technique requires specialized equipment and may be more expensive than other minimally invasive procedures, it is expected that these limitations will become less significant over time as robotic technology becomes more widely available and costs decrease. It is the authors' opinion that robotic assisted Heller myotomy should be considered as a feasible treatment option, in the field of minimally invasive treatments, for achalasia.

Achalasia is a primary neurodegenerative esophageal motility disorder characterized by abnormal peristalsisand failure of the lower esophageal sphincter to relax1. Treatment of achalasia aims to reduce the resting pressure of the lower esophageal sphincter, thereby allowing esophageal emptying2. There are multiple options for treating achalasia, such as oral pharmacologic therapy, endoscopic pharmacologic therapy3, pneumatic dilatation4, peroral endoscopic myotomy (POEM)5, and surgical myotomy6.
Surgical myotomy, in which the muscle fibers of the lower esophageal sphincter are divided, has been described as one of the three definitive therapies for non-advanced achalasia, along with pneumatic dilatation and peroral endoscopic myotomy7,8. The addition of a fundoplication is performed as an anti-reflux procedure since the myotomy reduces the pressure of the lower esophageal sphincter, which can result in potential gastroesophageal reflux disease9,10.
Laparoscopic Heller myotomy has become the most common surgical procedure for treating achalasia due to decreased postoperative pain and reduced morbidity compared to other surgical approaches, such as thoracotomy, laparotomic, and thoracoscopic11,12. Robotic Heller myotomy has emerged as a minimally invasive alternative to laparoscopy for treating achalasia because of mechanical advantages provided by the robotic approach, such as magnified high-resolution three-dimensional visualization and minimized physiological tremor13,14,15.
This article presents a case of a 32-year-old patient with chronic dysphagia, regurgitation, and weight loss. The dysphagia was initially associated with solids, slowly progressing to liquids as well. The patient denied other clinical symptoms, such as pyrosis, epigastric pain, and postprandial fullness. An endoscopic evaluation was initially performed in order to exclude malignancy (Figure 1). The exam revealed dilatation and tortuosity of the esophagus, as well as retention of food, which was completely aspirated with the endoscope. Thickening of the mucosa was also identified, and no neoplastic lesions were detected. Narrow band imaging showed normal vascular and mucosal patterns. The gastroesophageal junction was located at the level of the diaphragmatic crus.
The investigation then proceeded with an esophageal manometry (Figure 2) and a barium esophagram (Figure 3). The manometry showed impaired gastroesophageal junction relaxation and esophagus with the absence of peristalsis. Barium esophagram findings were esophageal dilatation and delayed emptying of the barium. The diagnosis of achalasia was then established by the findings on the manometry and barium esophagram. The patient was considered eligible for robotic-assisted myotomy and partial fundoplication.
The aim of this article is to provide a step-by-step description of a robot-assisted Heller myotomy, performed at the University of S&#227;o Paulo.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Da Vinci Surgical System</td>
			<td>Intuitive Surgical</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Needle driver</td>
			<td>Intuitive Surgical</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bipolar forceps</td>
			<td>Intuitive Surgical</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bipolar Fenestrated Grasper</td>
			<td>Intuitive Surgical</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Ultracision</td>
			<td>Johnson &#38;&#160; Johnson</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

robotic myotomy and partial fundoplication for achalasia

Laparoscopic Heller myotomy is currently considered the standard definitive treatment of achalasia. With the advancements in technology, robotic Heller myotomy has emerged as an alternative approach to traditional laparoscopy due to three-dimensional (3D) visualization, fine motor control, and improved ergonomics provided by the robot. 
Although there is a lack of randomized controlled trials, robotic-assisted Heller myotomy seems to be associated with lower rates of intraoperative perforations compared to the laparoscopic approach. A robotic approach may also improve surgical outcomes by providing a more complete myotomy. 
Here, we describe the detailed steps of robotic myotomy and partial fundoplication for achalasia.

Representative results are shown in Table 1. The operation time was 112 min with a measured blood loss of 20 mL. The postoperative course was uncomplicated. The post-operative care was carried out in a regular hospital room. There was no need for an intensive care unit since there were no complications. A liquid diet was started after day one of the surgery - the patient did not report dysphagia. The patient was discharged in good condition on postoperative day 2, on a liquid diet. Soft food was gradually introduced, after day 5. The patient did not develop any complications during the follow-up. A barium esophagram was performed 30 days after surgery, (Figure 5). The exam showed an adequate emptying of the barium, with no contrast retention and a normal aspect of the fundoplication.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/64822/64822fig01.jpg" /> 
Figure 1: Endoscopy. The preoperative endoscopy showed no signs of malignancy or other diseases of the esophagus. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/64822/64822fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/64822/64822fig02.jpg" /> 
Figure 2: Manometry. This figure displays the results of a high-resolution esophageal manometry study in a patient with suspected esophageal motility disorder. The plot shows the pressure waves detected along the length of the esophagus during a series of swallows. In this case, there is a complete absence of peristaltic contractions and no detectable pressurization of the esophageal lumen. These findings are consistent with a diagnosis of achalasia type I. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/64822/64822fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/64822/64822fig03.jpg" /> 
Figure 3: Barium esophagram. On the preoperative esophagogram, typical signs of achalasia were observed, including dilation of the distal esophagus, stasis of contrast material, and absence of air in the stomach. These findings are consistent with impaired esophageal emptying due to a failure of the lower esophageal sphincter to relax properly, which is characteristic of achalasia. The esophagus in this patient dilates up to 6 cm, indicating a grade III megaesophagus according to the Rezende-Mascarenhas classification. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/64822/64822fig03large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/64822/64822fig04.jpg" /> 
Figure 4: Trocar placement. The trocars are positioned in a linear arrangement directly above the umbilicus, with a distance of 28cm from the sternal angle. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/64822/64822fig04large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 5" class="xfigimg" src="/files/ftp_upload/64822/64822fig05.jpg" /> 
Figure 5: Postoperative barium esophagram. The postoperative esophagogram reveals improved contrast clearance from the esophagus to the stomach, along with a reduction in esophageal stasis. These findings suggest that the surgical intervention has been successful in improving esophageal motility and facilitating the emptying of ingested material into the stomach. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/64822/64822fig05large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Operation time</td>
			<td>112 minutes</td>
		</tr>
		<tr>
			<td>Blood loss</td>
			<td>20 ml</td>
		</tr>
		<tr>
			<td>Hospital discharge</td>
			<td>2 days</td>
		</tr>
	</tbody>
</table>
Table 1: Postoperative outcomes.

Watch this Scientific Journal Video about Robotic Myotomy and Partial Fundoplication for Achalasia at JoVE.com

Robotic Myotomy and Partial Fundoplication for Achalasia

Surgical myotomy with a partial fundoplication may be used in selected patients as a definitive treatment for achalasia. This article provides a step-by-step description of a robotic myotomy and partial fundoplication in a 32-year-old patient with megaesophagus.

Laparoscopic Heller myotomy is currently considered the standard definitive treatment of achalasia. With the advancements in technology, robotic Heller ...

robotic-myotomy-and-partial-fundoplication-for-achalasia

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1.3K Views.  University of São Paulo. Surgical myotomy with a partial fundoplication may be used in selected patients as a definitive treatment for achalasia. This article provides a step-by-step description of a robotic myotomy and partial fundoplication in a 32-year-old patient with megaesophagus. 

Video: Robotic Myotomy and Partial Fundoplication for Achalasia

Remote Magnetic Navigation for Accurate, Real-time Catheter Positioning and Ablation in Cardiac Electrophysiology Procedures

New remote navigation systems have been developed to improve current limitations of conventional manually guided catheter ablation in complex cardiac substrates such as left atrial flutter. This protocol describes all the clinical and invasive interventional steps performed during a human electrophysiological study and ablation to assess the accuracy, safety and real-time navigation of the Catheter Guidance, Control and Imaging (CGCI) system. Patients who underwent ablation of a right or left atrium flutter substrate were included. Specifically, data from three left atrial flutter and two counterclockwise right atrial flutter procedures are shown in this report. One representative left atrial flutter procedure is shown in the movie. This system is based on eight coil-core electromagnets, which generate a dynamic magnetic field focused on the heart. Remote navigation by rapid changes (msec) in the magnetic field magnitude and a very flexible magnetized catheter allow real-time closed-loop integration and accurate, stable positioning and ablation of the arrhythmogenic substrate.

This report provides a detailed description of a new remote navigation system based on magnetic driven forces, which has been recently introduced as a new robotic tool for human cardiac electrophysiology procedures.

New remote navigation systems have been developed to improve current limitations of conventional manually guided catheter ablation in complex cardiac ...

Surgical Procedures for a Rat Model of Partial Orthotopic Liver Transplantation with Hepatic Arterial Reconstruction

Orthotopic liver transplantation (OLT) in rats using a whole or partial graft is an indispensable experimental model for transplantation research, such as studies on graft preservation and ischemia-reperfusion injury 1,2, immunological responses 3,4, hemodynamics 5,6, and small-for-size syndrome 7. The rat OLT is among the most difficult animal models in experimental surgery and demands advanced microsurgical skills that take a long time to learn. Consequently, the use of this model has been limited. Since the reliability and reproducibility of results are key components of the experiments in which such complex animal models are used, it is essential for surgeons who are involved in rat OLT to be trained in well-standardized and sophisticated procedures for this model.
While various techniques and modifications of OLT in rats have been reported 8 since the first model was described by Lee et al. 9 in 1973, the elimination of the hepatic arterial reconstruction 10 and the introduction of the cuff anastomosis technique by Kamada et al. 11 were a major advancement in this model, because they simplified the reconstruction procedures to a great degree. In the model by Kamada et al., the hepatic rearterialization was also eliminated. Since rats could survive without hepatic arterial flow after liver transplantation, there was considerable controversy over the value of hepatic arterialization. However, the physiological superiority of the arterialized model has been increasingly acknowledged, especially in terms of preserving the bile duct system 8,12 and the liver integrity 8,13,14.
In this article, we present detailed surgical procedures for a rat model of OLT with hepatic arterial reconstruction using a 50% partial graft after ex vivo liver resection. The reconstruction procedures for each vessel and the bile duct are performed by the following methods: a 7-0 polypropylene continuous suture for the supra- and infrahepatic vena cava; a cuff technique for the portal vein; and a stent technique for the hepatic artery and the bile duct.

Orthotopic liver transplantation in rats is an indispensable experimental model for biomedical research. Here we present our surgical procedures for orthotopic rat liver transplantation with hepatic arterial reconstruction using a 50% partial graft.

Orthotopic liver transplantation (OLT) in rats using a whole or partial graft is an indispensable experimental model for transplantation research, such as ...

Robotic Ablation of Atrial Fibrillation

Background: Pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). During PVI an electrical conduction block between pulmonary vein (PV) and left atrium (LA) is created. This conduction block prevents AF, which is triggered by irregular electric activity originating from the PV. However, transmural atrial lesions are required which can be challenging. Re-conduction and AF recurrence occur in 20 - 40% of the cases. Robotic catheter systems aim to improve catheter steerability. Here, a procedure with a new remote catheter system (RCS), is presented. Objective of this article is to show feasibility of robotic AF ablation with a novel system. Materials and Methods: After interatrial trans-septal puncture is performed using a long sheath and needle under fluoroscopic guidance. The needle is removed and a guide wire is placed in the left superior PV. Then an ablation catheter is positioned in the LA, using the sheath and wire as guide to the LA. LA angiography is performed over the sheath. A circular mapping catheter is positioned via the long sheath into the LA and a three-dimensional (3-D) anatomical reconstruction of the LA is performed. The handle of the ablation catheter is positioned in the robotic arm of the Amigo system and the ablation procedure begins. During the ablation procedure, the operator manipulates the ablation catheter via the robotic arm with the use of a remote control. The ablation is performed by creating point-by-point lesions around the left and right PV ostia. Contact force is measured at the catheter tip to provide feedback of catheter-tissue contact. Conduction block is confirmed by recording the PV potentials on the circular mapping catheter and by pacing maneuvers. The operator stays out of the radiationfield during ablation. Conclusion: The novel catheter system allows ablation with high stability on low operator fluoroscopy exposure.

Pulmonary vein isolation (PVI) with an ablation catheter is a curative treatment for atrial fibrillation (AF). Robotic catheter systems aim to improve catheter steerability. Here, a procedure with a new robotic catheter system is presented. The goal of the procedure is electrical block between pulmonary vein and left atrium.

Background: Pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). During PVI an electrical conduction block between ...

Visualization of Vascular and Parenchymal Regeneration after 70% Partial Hepatectomy in Normal Mice

A modified silicone injection procedure was used for visualization of the hepatic vascular tree. This procedure consisted of in-vivo injection of the silicone compound, via a 26 G catheter, into the portal or hepatic vein. After silicone injection, organs were explanted and prepared for ex-vivo micro-CT (&#181;CT) scanning. The silicone injection procedure is technically challenging. Achieving a successful outcome requires extensive microsurgical experience from the surgeon. One of the challenges of this procedure involves determining the adequate perfusion rate for the silicone compound. The perfusion rate for the silicone compound needs to be defined based on the hemodynamic of the vascular system of interest. Inappropriate perfusion rate can lead to an incomplete perfusion, artificial dilation and rupturing of vascular trees.
The 3D reconstruction of the vascular system was based on CT scans and was achieved using preclinical software such as HepaVision. The quality of the reconstructed vascular tree was directly related to the quality of silicone perfusion. Subsequently computed vascular parameters indicative of vascular growth, such as total vascular volume, were calculated based on the vascular reconstructions. Contrasting the vascular tree with silicone allowed for subsequent histological work-up of the specimen after &#181;CT scanning. The specimen can be subjected to serial sectioning, histological analysis and whole slide scanning, and thereafter to 3D reconstruction of the vascular trees based on histological images. This is the prerequisite for the detection of molecular events and their distribution with respect to the vascular tree. This modified silicone injection procedure can also be used to visualize and reconstruct the vascular systems of other organs. This technique has the potential to be extensively applied to studies concerning vascular anatomy and growth in various animal and disease models.

Tools used for visualizing vascular regeneration require methods for contrasting the vascular trees. This film demonstrated a delicate injection technique used to achieve optimal contrasting of the vascular trees and illustrate the potential benefits resulting from a detailed analysis of the resulting specimen using &#181;CT and histological serial sections.

A modified silicone injection procedure was used for visualization of the hepatic vascular tree. This procedure consisted of in-vivo injection of the ...

Complete and Partial Aortic Occlusion for the Treatment of Hemorrhagic Shock in Swine

Hemorrhage remains the leading cause of preventable deaths in trauma. Endovascular management of non-compressible torso hemorrhage has been at the forefront of trauma care in recent years. Since complete aortic occlusion presents serious concerns, the concept of partial aortic occlusion has gained a growing attention. Here, we present a large animal model of hemorrhagic shock to investigate the effects of a novel partial aortic balloon occlusion catheter and compare it with a catheter that works on the principles of complete aortic occlusion. Swine are anesthetized and instrumented in order to conduct controlled fixed-volume hemorrhage, and hemodynamic and physiological parameters are monitored. Following hemorrhage, aortic balloon occlusion catheters are inserted and inflated in the supraceliac aorta for 60 min, during which the animals receive whole-blood resuscitation as 20% of the total blood volume (TBV). Following balloon deflation, the animals are monitored in a critical care setting for 4 h, during which they receive fluid resuscitation and vasopressors as needed. The partial aortic balloon occlusion demonstrated improved distal mean arterial pressures (MAPs) during the balloon inflation, decreased markers of ischemia, and decreased fluid resuscitation and vasopressor use. As swine physiology and homeostatic responses following hemorrhage have been well-documented and are like those in humans, a swine hemorrhagic shock model can be used to test various treatment strategies. In addition to treating hemorrhage, aortic balloon occlusion catheters have become popular for their role in cardiac arrest, cardiac and vascular surgery, and other high-risk elective surgical procedures.

Here, we present a protocol demonstrating a hemorrhagic shock model in swine that uses aortic occlusion as a bridge to definitive care in trauma. This model has application in testing a wide range of surgical and pharmacological therapeutic strategies.

Hemorrhage remains the leading cause of preventable deaths in trauma. Endovascular management of non-compressible torso hemorrhage has been at the ...

Generation of a Rat Model of Acute Liver Failure by Combining 70% Partial Hepatectomy and Acetaminophen

Acute liver failure (ALF) is a clinical condition caused by various etiologies resulting in the loss of metabolic, biochemical, synthesizing, and detoxifying functions of the liver. In most irreversible liver damage cases, orthotropic liver transplant (OLT) remains the only available treatment. To study the therapeutic potential of a treatment for ALF, its prior testing in an animal model of ALF is essential. In the current study, an ALF model in rats was developed by combining 70% partial hepatectomy (PHx) and injections of acetaminophen (APAP) that provides a therapeutic window of 48 h. The median and left lateral lobes of the liver were removed to excise 70% of the liver mass and APAP was given 24 h postsurgically for 2 days. Survival in ALF-induced animals was found to be severely decreased. The development of ALF was confirmed by altered serum levels of the enzymes alanine amino transferase (ALT), aspartate amino transferase (AST), alkaline phosphatase (ALP); changes in prothrombin time (PT); and assessment of the international normalized ratio (INR). Study of the gene expression profile by qPCR revealed an increase in expression levels of genes involved in apoptosis, inflammation, and in the progression of liver injury. Diffused degeneration of hepatocytes and infiltration of immune cells was observed by histological evaluation. The reversibility of ALF was confirmed by the restoration of survival and serum levels of ALT, AST, and ALP after intrasplenic transplantation of syngeneic healthy rat hepatocytes. This model presents a reliable alternative to the available ALF animal models to study the pathophysiology of ALF as well as to evaluate the potential of a novel therapy for ALF. The use of two different approaches also makes it possible to study the combined effect of physical and drug-induced liver injury. The reproducibility and feasibility of current procedure is an added benefit of the model.

The acute liver failure animal model developed in the current study presents a feasible alternative for the study of potential therapies. The current model employs the combined effect of physical and drug-induced hepatic injury and provides a suitable time window to study the potential of novel therapies.

Acute liver failure (ALF) is a clinical condition caused by various etiologies resulting in the loss of metabolic, biochemical, synthesizing, and ...

Robotic Lateral Pancreaticojejunostomy for Chronic Pancreatitis

Lateral pancreaticojejunostomy (LPJ) has shown good postoperative outcomes in patients with painful, morphine dependent, chronic pancreatitis (CP). The recent rise of robotic and laparoscopic pancreatic surgery has found benefits such as reduced time to functional recovery. Few studies have reported on the feasibility, technique and outcome of robotic LPJ, especially including transection of the gastroduodenal artery. The present study describes the main steps for robotic LPJ in a patient with painful chronic pancreatitis with a dilated main pancreatic duct. The patient underwent robotic LPJ. The LPJ anastomosis is performed using a running suture technique in a longitudinal side-to-side manner. Routinely, the gastroduodenal artery is transected to drain the entire length of the main pancreatic duct. The patient is in French position; 7 trocars are placed (4 robotic, 2 laparoscopic assistants, 1 liver-retractor). After docking of the robot system, the omental bursa is opened, and the right gastroepiploic artery and vein are ligated at their base at the lower border of the pancreas. Intraoperative ultrasonography is performed in order to determine trajectory of the dilated main pancreatic duct which is opened for its entire length after the gastroduodenal artery has been suture ligated both cranially and caudally from the main pancreatic duct. A Roux limb is created, and a latero-lateral PJ is fashioned using several 3-0 barbed sutures. A stapled jejuno-jejunostomy is created at sufficient distance from the pancreatic anastomosis, aided by a 50 cm suture. The described technique for robotic LPJ is a complex but feasible operation for patients with treatment refractory CP and a dilated main pancreatic duct. Due to its complexity, implementation in high volume centers with extensive experience with CP surgery may improve outcomes.

Robotic lateral pancreaticojejunostomy (RLPJ) may be used in patients with painful, morphine dependent, chronic pancreatitis and a dilated main pancreatic duct. We describe a standardized and reproducible technique for RLPJ, which includes transection of the gastroduodenal artery.

Lateral pancreaticojejunostomy (LPJ) has shown good postoperative outcomes in patients with painful, morphine dependent, chronic pancreatitis (CP). The ...

Robotic Taj Mahal Hepatectomy for Hilar Cholangiocarcinoma

Hilar cholangiocarcinoma is the most common malignant tumor of the biliary tract. Radical surgical resection is the only effective treatment option. In this study, a 32-year-old male patient with Bismuth Type IVa hilar cholangiocarcinoma underwent radical robotic resection of hepatic S4b, S5, and S1 (Taj Mahal hepatectomy) combined with regional lymphadenectomy, hilar bile duct reconstruction, and hepaticojejunostomy by the robotic surgical system. Postoperative pathological examination showed moderately-differentiated adenocarcinoma of the hilar bile duct. The surgical margins of the liver and bile ducts were negative. Recovery was smooth and the patient was discharged on the 17th postoperative day. The robotic surgical system and associated multiple instruments along with flexible and precise movements is suitable for the local hepatectomy around the porta hepatis, and delicate reconstruction of the hilar bile duct with a smaller diameter. This first clinical application study found that robotic Taj Mahal hepatectomy for hilar cholangiocarcinoma is safe and feasible and needs more experience for the evaluation of its long-term outcomes.

Robotic resection of hepatic S4b, S5, and S1 using the Taj Mahal procedure is feasible and safe for selected patients with hilar cholangiocarcinoma. The step-by-step details for this surgery are presented here.

Hilar cholangiocarcinoma is the most common malignant tumor of the biliary tract. Radical surgical resection is the only effective treatment option. In ...

Complete and Partial Resuscitative Endovascular Balloon Occlusion of the Aorta for Hemorrhagic Shock

Resuscitative endovascular balloon occlusion of the aorta (REBOA) devices grew out of a military-civilian partnership to develop new capabilities for hemorrhage control. With the advent of purpose-built devices, REBOA has become increasingly common in civilian trauma and acute care settings. Currently available REBOA catheters were designed as complete aortic occlusion devices. However, the therapeutic window for complete aortic occlusion is time-limited due to ischemia-reperfusion injury. The partial procedure allows blood flow past the level of occlusion while maintaining targeted proximal pressure, which has been shown to reduce distal ischemia and adjunctive resuscitation requirements in preclinical studies with prolonged occlusion times as compared to traditional complete occlusion.
pREBOA-PRO is the first catheter designed to enable partial and complete aortic occlusion and is currently in limited market release at seven Level I trauma centers in North America. This paper will focus on procedural considerations for REBOA, including patient selection criteria and a comparison of complete and partial aortic occlusion in a simulator, along with highlighting critical steps to improve clinical outcomes. Additionally, this paper reviews a contrast-enhanced CT scan from a trauma patient that shows distal perfusion after 2 h of partial aortic occlusion using this newly designed catheter and discusses representative results from the limited market release to highlight the profound effect of technological innovation on outcomes in vascular emergencies.

A commercial catheter was designed to facilitate true partial resuscitative endovascular balloon occlusion of the aorta (REBOA) and address the complications associated with complete aortic occlusion. Initial clinical reports indicate that partial REBOA improves transition to reperfusion, reduction of distal ischemia, and extension of safe occlusion time compared to complete occlusion.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) devices grew out of a military-civilian partnership to develop new capabilities for ...

Robotic Cochlear Implantation for Direct Cochlear Access

Robot-assisted systems offer great potential for gentler and more precise cochlear implantation. In this article, we provide a comprehensive overview of the clinical workflow for robotic cochlear implantation using a robotic system specifically developed for a minimally invasive, direct cochlear access. The clinical workflow involves experts from various disciplines and requires training to ensure a smooth and safe procedure. The protocol briefly summarizes the history of robotic cochlear implantation. The clinical sequence is explained in detail, beginning with the assessment of patient eligibility and covering surgical preparation, preoperative planning with the special planning software, drilling of the middle ear access, intraoperative imaging to confirm the trajectory, milling of the inner ear access, insertion of the electrode array, and implant management. The steps that require special attention are discussed. As an example, the postoperative outcome of robotic cochlear implantation in a patient with advanced otosclerosis is presented. Finally, the procedure is discussed in the context of the authors' experience.

Robotic cochlear implantation is a procedure for minimally invasive inner ear access. Compared to conventional surgery, robotic cochlear implantation involves additional steps that need to be carried out in the operating room. In this article we give a description of the procedure and highlight the important aspects of robotic cochlear implantation.

Robot-assisted systems offer great potential for gentler and more precise cochlear implantation. In this article, we provide a comprehensive overview of ...