This research was not supported by any grants.

The protocol was conducted in accordance with the Declaration of Helsinki and the protocol was approved by the Institutional Review Board at the First Affiliated Hospital of Sun Yat-sen University.
1. Patient selection
<ol>
	<li>Diagnose achalasia by clinical manifestations and diagnostic testing (barium esophagram, high-resolution manometry (HRM), and upper endoscopy)10: the presence of symptoms such as dysphagia, regurgitation, chest pain, and weight loss; the &#34;bird&#39;s-beak&#34; appearance on barium esophagram; impaired relaxation of the lower esophageal sphincter and absent peristalsis on the results of HRM; and ruling out malignancy by upper endoscopy.</li>
	<li>Use the following inclusion criteria: diagnosis of achalasia; Eckardt score11 &#62; 3; age between 18-80 years; written informed consent for POEM using the scissor-type knife.</li>
	<li>Use the following exclusion criteria: coagulopathy and systemic disorders that precluded safe general anesthesia; pregnancy; ulcerated esophagitis.</li>
</ol>
2. Preoperative preparations
<ol>
	<li>Administer a liquid only diet 1 day before the POEM procedure.</li>
	<li>Administer intravenous antibiotics (Cefazolin) and proton pump inhibitors (PPIs) 30 min before the induction of anesthesia.</li>
	<li>Perform an upper endoscopy to aspirate any residual contents to reduce the risk of aspiration immediately before the induction of anesthesia.</li>
	<li>Administer general anesthesia (propofol) with endotracheal intubation.</li>
	<li>Place the patient in a supine position.</li>
</ol>
3. Surgical technique with a scissor type knife for the POEM procedure
NOTE: See Figure 1 for the POEM procedure using a scissor-type knife.
<ol>
	<li>Identify the EGJ by the puckered and tight appearance. Confirm the increased resistance when maneuvering the endoscope through the EGJ. Note the location of the EGJ by measuring the distance from the incisors.</li>
	<li>Choose an injection point 7 to 9 cm proximal to the EGJ in the posterior wall (the 5-6 o&#39;clock position) of the esophagus. Inject saline with methylene blue into the submucosal space with an endoscopic injection needle. 
	NOTE: Use an extended proximal injection point for patients with Chicago type III achalasia.</li>
	<li>Make a 1.5 to 2 cm longitudinal mucosal incision with the scissor-type knife (endocut Q mode: effect 3, duration 2, interval 4).</li>
	<li>Rotate the blades of the scissor-type knife parallel to the muscle layer. Then grasp and dissect (endocut Q mode: effect 3, duration 2, interval 4) the submucosa tissue to create a submucosal tunnel to a location 2 to 3 cm below the EGJ. Keep the dissection plane close to the muscle layer. Inject saline with methylene blue into the submucosal tissue to expand the working space with tunnel progression.</li>
	<li>Confirm the adequate submucosal tunnel length by the blue discoloration of the gastric mucosa on the retroflexed view.</li>
	<li>Use the scissor-type knife for intraoperative vessel sealings and bleeding controls (forced coagulation mode: effect 2, 50 W) without changing the hemostatic forceps.</li>
	<li>Begin the anterograde myotomy at approximately 2 cm distal to the mucosal entry. Selectively grasp and dissect (endocut Q mode: effect 3, duration 2, interval 4) the internal circular muscle bundle with the scissor-type knife. Extend the myotomy 2 to 3 cm onto the gastric cardia.</li>
	<li>After the completion of myotomy, confirm the smooth passage through the EGJ by reinserting the endoscope into the esophageal lumen.</li>
	<li>Close the mucosal entry with endoclips.</li>
</ol>
4. Postoperative management
<ol>
	<li>Admit patients to the inpatient ward following the POEM procedure for observation.</li>
	<li>Administer intravenous antibiotics for 24 h after the POEM procedure. Continue the intravenous PPIs until discharge, and then switch to the oral PPIs (single dose) for 6 weeks.</li>
	<li>Initiate a liquid diet 24 h after the POEM procedure. At discharge, instruct patients to adhere to a soft diet for 2 weeks, and then resume regular diet gradually.</li>
</ol>
5. Follow-up
<ol>
	<li>Schedule an initial follow-up by outpatient visits and telephone interviews at 3 months postoperatively.</li>
	<li>At the follow-up visit, obtain standardized questionnaires from patients, including Eckardt scores11, GerdQ scores12, body weight, and information about PPIs use. Schedule objective tests, including HRM, barium esophagram, and upper endoscopy.</li>
</ol>

<ol><li>Khashab, M. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((ASGE+guideline+on+the+management+of+achalasia%5BTitle%5D)+AND+%22Gastrointestinal+Endoscopy%22%5BJournal%5D)">ASGE guideline on the management of achalasia.</a> Gastrointestinal Endoscopy. 91 (2), 213-227 (2020).</li>
<li>Liu, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Comprehensive+evaluation+of+the+learning+curve+for+peroral+endoscopic+myotomy%5BTitle%5D)+AND+%22Clinical+Gastroenterology+and+Hepatology%22%5BJournal%5D)">Comprehensive evaluation of the learning curve for peroral endoscopic myotomy.</a> Clinical Gastroenterology and Hepatology. 16 (9), 1420-1426 (2018).</li>
<li>Patel, K. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+light+at+the+end+of+the+tunnel%3A+a+single-operator+learning+curve+analysis+for+per+oral+endoscopic+myotomy%5BTitle%5D)+AND+%22Gastrointestinal+Endoscopy%22%5BJournal%5D)">The light at the end of the tunnel: a single-operator learning curve analysis for per oral endoscopic myotomy.</a> Gastrointestinal Endoscopy. 81 (5), 1181-1187 (2015).</li>
<li>Cai, M. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Peroral+endoscopic+myotomy+for+idiopathic+achalasia%3A+randomized+comparison+of+water-jet+assisted+versus+conventional+dissection+technique%5BTitle%5D)+AND+%22Surgical+Endoscopy%22%5BJournal%5D)">Peroral endoscopic myotomy for idiopathic achalasia: randomized comparison of water-jet assisted versus conventional dissection technique.</a> Surgical Endoscopy. 28 (4), 1158-1165 (2014).</li>
<li>Tanaka, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Peroral+endoscopic+myotomy+using+FlushKnife+BT%3A+a+single-center+series%5BTitle%5D)+AND+%22Endoscopy+International+Open%22%5BJournal%5D)">Peroral endoscopic myotomy using FlushKnife BT: a single-center series.</a> Endoscopy International Open. 5 (7), 663-669 (2017).</li>
<li>Oka, S., Tanaka, S., Takata, S., Kanao, H., Chayama, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Usefulness+and+safety+of+SB+knife+Jr+in+endoscopic+submucosal+dissection+for+colorectal+tumors%5BTitle%5D)+AND+%22Digestive+Endoscopy%22%5BJournal%5D)">Usefulness and safety of SB knife Jr in endoscopic submucosal dissection for colorectal tumors.</a> Digestive Endoscopy. 24, 90-95 (2012).</li>
<li>Yoshida, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Efficacy+of+scissor-type+knives+for+endoscopic+mucosal+dissection+of+superficial+gastrointestinal+neoplasms%5BTitle%5D)+AND+%22Digestive+Endoscopy%22%5BJournal%5D)">Efficacy of scissor-type knives for endoscopic mucosal dissection of superficial gastrointestinal neoplasms.</a> Digestive Endoscopy. 32 (1), 4-15 (2020).</li>
<li>Kuwai, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Endoscopic+submucosal+dissection+of+early+colorectal+neoplasms+with+a+monopolar+scissor-type+knife%3A+short-+to+long-term+outcomes%5BTitle%5D)+AND+%22Endoscopy%22%5BJournal%5D)">Endoscopic submucosal dissection of early colorectal neoplasms with a monopolar scissor-type knife: short- to long-term outcomes.</a> Endoscopy. 49 (9), 913-918 (2017).</li>
<li>Yamashina, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Scissor-type+knife+significantly+improves+self-completion+rate+of+colorectal+endoscopic+submucosal+dissection%3A+Single-center+prospective+randomized+trial%5BTitle%5D)+AND+%22Digestive+Endoscopy%22%5BJournal%5D)">Scissor-type knife significantly improves self-completion rate of colorectal endoscopic submucosal dissection: Single-center prospective randomized trial.</a> Digestive Endoscopy. 29 (3), 322-329 (2017).</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/pubmed?term=((ACG+clinical+guidelines%3A+diagnosis+and+management+of+achalasia%5BTitle%5D)+AND+%22The+American+Journal+of+Gastroenterology%22%5BJournal%5D)">ACG clinical guidelines: diagnosis and management of achalasia.</a> The American Journal of Gastroenterology. 115 (9), 1393-1411 (2020).</li>
<li>Eckardt, A. J., Eckardt, V. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Treatment+and+surveillance+strategies+in+achalasia%3A+an+update%5BTitle%5D)+AND+%22Nature+Reviews.+Gastroenterology+and+Hepatology%22%5BJournal%5D)">Treatment and surveillance strategies in achalasia: an update.</a> Nature Reviews. Gastroenterology and Hepatology. 8 (6), 311-319 (2011).</li>
<li>Jones, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Development+of+the+GerdQ%2C+a+tool+for+the+diagnosis+and+management+of+gastro-oesophageal+reflux+disease+in+primary+care%5BTitle%5D)+AND+%22Alimentary+Pharmacology+%26+Therapeutics%22%5BJournal%5D)">Development of the GerdQ, a tool for the diagnosis and management of gastro-oesophageal reflux disease in primary care.</a> Alimentary Pharmacology & Therapeutics. 30 (10), 1030-1038 (2009).</li>
<li>Bittinger, M., Messmann, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Use+of+the+stag-beetle+knife+for+peroral+endoscopic+myotomy+for+achalasia%3A+a+novel+method+for+myotomy%5BTitle%5D)+AND+%22Gastrointestinal+Endoscopy%22%5BJournal%5D)">Use of the stag-beetle knife for peroral endoscopic myotomy for achalasia: a novel method for myotomy.</a> Gastrointestinal Endoscopy. 82 (2), 401-402 (2015).</li>
<li>Hathorn, K. E., Chan, W. W., Aihara, H., Thompson, C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Determining+the+safety+and+effectiveness+of+electrocautery+enhanced+scissors+for+peroral+endoscopic+myotomy+%28with+Video%29%5BTitle%5D)+AND+%22Clinical+Endoscopy%22%5BJournal%5D)">Determining the safety and effectiveness of electrocautery enhanced scissors for peroral endoscopic myotomy (with Video).</a> Clinical Endoscopy. 53 (4), 443-451 (2020).</li>
<li>Mohan, B. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Anterior+versus+posterior+approach+in+peroral+endoscopic+myotomy+%28POEM%29%3A+a+systematic+review+and+meta-analysis%5BTitle%5D)+AND+%22Endoscopy%22%5BJournal%5D)">Anterior versus posterior approach in peroral endoscopic myotomy (POEM): a systematic review and meta-analysis.</a> Endoscopy. 52 (4), 251-258 (2020).</li>
</ol>

The authors have nothing to disclose.

As an evolving endoscopic surgical treatment for achalasia, POEM requires both advanced endoscopic skills and knowledge of surgical anatomy. A recent study demonstrated that POEM comes with a considerable learning curve that increases the risk of technical failure, adverse events, and clinical failure2. Endoscopists, especially trainees who have not completed their learning phase, commonly face difficulty in accurate manipulations of the endoscopic knife while working near the EGJ with limited working space and less distinct tissue planes. This may result in inadvertent injury, unexpected bleeding, and inadequate myotomy.
Endoscopic needle-type knives have been used since the development of POEM. However, using the needle-type knife requires advanced endoscopic techniques to achieve a safe and adequate selective myotomy, while additional hemostatic forceps are frequently needed for managing large vessels and active bleeding. Unlike the needle-type knife, the scissor-type knife enables coagulation and dissection after grasping the target tissue. The confirmation of the cutting line after grasping improves the accuracy and reliability of dissection and minimizes the risk of tissue injury, which was particularly useful for the selective myotomy of the internal circular muscle. In addition, the scissor-type knife can function as hemostatic forceps and enables precoagulation and hemostasis without device replacement. In the three POEM procedures reported here, all hemostasis and vessel sealings were achieved by the scissor-type knife without using the hemostatic forceps. Furthermore, the tip of the scissor-type knife also has the capability of rotation and an insulated external coating. The capability of rotation offered endoscopists high flexibility for manipulations even at the level of the EGJ, while the insulated external coating of the two blades could protect the surrounding tissue from thermal damage.
The appropriate selection of endoscopic devices is essential for a safe and effective POEM procedure. The operators' skills and patient characteristics were two important factors to consider in the selection of devices. The characteristics of the scissor-type knife are helpful to minimize the technical difficulty and improve the safety of the POEM procedures, which make it an appropriate device for the trainees during the learning curve phase. Under the supervision of endoscopic specialists, trainees can get verbal agreement on the cutting line of the scissor-type knife before the next dissection. Additionally, the scissor-type knife has better hemostatic capability and could be used as a substitute for additional hemostatic forceps. Thus, the scissor-type knife may be suitable in situations when a high risk of intraoperative bleeding is predicted, such as in patients on antiplatelet or anticoagulant therapy.
Previous studies have shown the feasibility of using the scissor-type knife for myotomy during POEM procedures, while additional devices were still needed for mucosal incision and submucosal tunneling13,14. The present protocol describes our experience with the use of the scissor-type knife in assisting the whole POEM procedure. However, compared with water-jet equipped needle-type knife, the scissor-type knife is less efficient in submucosal tunneling and mucosal incision, which requires an exchange of accessories for submucosal injection and good cooperation between the endoscopist and the assistant. In technically challenging cases with submucosal fibrosis, the combined use of a needle-type knife (preferably equipped with a water-jet function) is recommended when the scissor-type knife alone may not be effective in dissecting fibrotic tissue. As for the orientation of myotomy, existing evidence showed that the anterior and posterior myotomy in POEM have comparable clinical outcomes in terms of clinical success, post-procedure GERD, and adverse events15, while the posterior approach allows for better alignment of the endoscopic accessories with the working channel of the endoscope. The use of the scissor-type knife for posterior POEM in this protocol may be helpful to minimize the technical difficulty.
There are several limitations in the present study. First, the present study showed our initial experience of using the scissor-type knife for POEM with a relatively small sample size and short-term follow-up. The favorable outcomes still need further validation. Second, there was no direct comparison data between the scissor-type knife and other needle-type knives. Therefore, future randomized controlled trials are warranted to evaluate the safety, efficacy, and learning curve for POEM using thescissor-type knife compared with the needle-type knife.
In conclusion, the use of the scissor-type knife could minimize the technical difficulty and improve the safety of the POEM procedures, which may be suitable for trainees during the learning curve phase. Future large randomized controlled trials are needed to confirm the safety, efficacy, and learning curve of using the scissor-type knife for POEM compared with conventional knives.

Peroral endoscopic myotomy (POEM) has gained worldwide acceptance as one of the first-line treatment modalities along with pneumatic dilation and Heller myotomy for patients with achalasia1. To date, most POEM procedures have been confined to a few high-volume, specialized centers. Previous studies have shown that even operators skilled in laparoscopy or endoscopy have a steep learning curve when they are beginning to perform POEM and a higher volume of cases is required to manage challenging situations and prevent adverse events2,3. During POEM procedures, endoscopic needle-knives are most commonly used for both submucosal tunneling and myotomy, combined with hemostatic forceps for managing large vessels and active bleeding. However, because of the impaired esophagogastric junction (EGJ) relaxation in patients with achalasia, the limited space at the level of the EGJ increases the technical difficulty of tissue plane dissection and selective myotomy using the needle-type knife. Besides, operators who are still in the learning phase could be less proficient in exchanging the hemostatic forceps for bleeding control, which may lead to poor visibility and even further inadvertent mucosal injury.
Various endoscopic knives have been used in the POEM procedures for better manipulations and safety profiles4,5. The junior scissor-type knife (Stag-beetle Knife Jr.) with two monopolar blades that are both insulated externally was originally developed for accurate manipulations in colorectal endoscopic submucosal dissection (ESD)6. The standard techniques used with the scissor-type knife involve grasping the target tissue, and then dissection or coagulation. Theoretically, tissue injury caused by unintentional movement could be avoided with a scissor-type knife as compared with a needle-type knife7. Several studies have demonstrated the feasibility and safety of using the scissor-type knife for all ESD procedures, including mucosal incision, submucosal dissection, and hemostasis7,8. Meanwhile, a recent randomized controlled trial showed that the scissor-type knife significantly improved the trainees' self-completion rates for colorectal ESD9. It can be speculated that these advantages of the scissor-type knife can promote a safer POEM procedure, especially during the trainee's early cases. To minimize the technical difficulty and improve the safety of POEM, we described a protocol for using a scissor-type knife for the main steps of the POEM procedure, including mucosal incision, submucosal tunneling, myotomy, and hemostasis. Three patients with achalasia who received POEM using the scissor-type knife were presented to evaluate the feasibility and clinical outcomes of this protocol.

<table><tbody><tr><td>Electrogenerator</td><td>ERBE Elektromedizin</td><td>VIO 200S</td><td></td></tr><tr><td>Endoclip</td><td>Micro-Tech (Nanjing)</td><td>ROCC-D-26-195-C</td><td></td></tr><tr><td>Endoscope</td><td>Olympus</td><td>GIF-H260</td><td></td></tr><tr><td>Injection Needle</td><td>Olympus</td><td>NM-400L-0423</td><td></td></tr><tr><td>Stag Beetle Knife Jr</td><td>Sumitomo Bakelite</td><td>MD-47703W</td><td></td></tr><tr><td>Transparent Distal Cap</td><td>Olympus</td><td>D-201-11804</td><td></td></tr></tbody></table>

use of the scissor-type knife during the peroral endoscopy myotomy procedure for the treatment of achalasia

Peroral endoscopic myotomy (POEM) is one of the first-line treatment modalities along with pneumatic dilation and Heller myotomy for patients with achalasia. Endoscopists, especially trainees during the learning phase, commonly face difficulty in tissue plane dissection and selective myotomy while working near the esophagogastric junction, with increased risks of inadvertent injury, unexpected bleeding, and inadequate myotomy. To minimize the technical difficulty and improve the safety of POEM, we describe a protocol for using a scissor-type knife for the main steps of POEM, including mucosal incision, submucosal tunneling, myotomy, and hemostasis. The standard techniques used with the scissor-type knife involve grasping the target tissue, and then dissection or coagulation. The confirmation of the cutting line after grasping improves the accuracy and reliability of dissection, which is particularly useful for the selective myotomy of the internal circular muscle. Meanwhile, the scissor-type knife provides enhanced hemostatic capability and enables hemostasis and pre-coagulation without the device exchange for hemostatic forceps. Evaluation of the clinical outcomes in three patients who successfully received POEM using the scissor-type knife revealed no perioperative adverse events. At the 3-month follow-up, all patients achieved clinical success with postoperative Eckardt scores ranging from 0 to 1. In conclusion, the use of a scissor-type knife could minimize the technical difficulty and improve the safety of the POEM procedures, which may be suitable for trainees during the learning phase.

Compared with the needle-type knife, the scissor-type knife enables coagulation and dissection after grasping the target tissue. Meanwhile, the scissor-type knife is equipped with an enhanced hemostatic capability similar to hemostatic forceps and insulated coating external of the two blades (Table 1). Three patients with achalasia received POEM using the scissor-type knife in our institution. Sigmoid esophagus was present in one patient. One patient had previously undergone pneumatic dilation. Technical success was achieved in all the patients with no occurrence of perioperative adverse events. All bleeding controls and vessel sealings in the three POEM procedures were managed by the scissor-type knife without the use of hemostatic forceps. The procedure time was 60, 45, and 40 min, respectively (Table 2).
At the 3-month follow-up, all patients achieved clinical success with postoperative Eckardt scores ranging from 0 to 1. The postoperative HRM and barium esophagram data showed significant reductions in lower esophageal sphincter pressure, 4-second&#160;integrated relaxation pressure, and esophageal diameter. One patient had an endoscopic finding of low-grade esophagitis (Los Angeles grade A) without reflux symptoms (Table 3).
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/63239/63239fig01.jpg" /> 
Figure 1: The procedure of peroral endoscopic myotomy using the scissor-type knife. (A) An image of the tight EGJ before POEM. (B) After submucosal injection, the mucosa in the posterior esophageal wall was incised by the scissor-type knife. (C) A submucosal tunnel was created using the scissor-type knife. (D) The selective myotomy of the internal circular muscle was performed using the scissor-type knife. (E) The mucosal entry was closed with endoclips. (F) An image of the relaxed EGJ after POEM. EGJ, esophagogastric junction; POEM, peroral endoscopic myotomy. <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/63239/63239fig01large.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>Parameters</td>
			<td>Scissor-type knife</td>
			<td>Needle-type knife</td>
		</tr>
		<tr>
			<td>Structure</td>
			<td>Scissor-type with a forceps length of 3.5 mm and a maximal open width of 4.5 mm&#160;</td>
			<td>Needle-type with lengths ranging between 1.5 and 4.5 mm</td>
		</tr>
		<tr>
			<td>Insulating coating</td>
			<td>Insulated coating external of the two blades</td>
			<td>No</td>
		</tr>
		<tr>
			<td>Dissection technique</td>
			<td>Grasp the tissue before dissection&#160;</td>
			<td>Hook the tissue before dissection</td>
		</tr>
		<tr>
			<td>Hemostatic capability</td>
			<td>Enhanced hemostatic capability similar to hemostatic forceps&#160;</td>
			<td>Usually combined with the use of&#160; hemostatic forceps</td>
		</tr>
		<tr>
			<td>Water-jet injection function</td>
			<td>No</td>
			<td>Equipped in some advanced needle-type knives</td>
		</tr>
	</tbody>
</table>
Table 1: The characteristics of the scissor-type knife in comparison with the needle-type knife.
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Parameters</td>
			<td>Patient 1</td>
			<td>Patient 2</td>
			<td>Patient 3</td>
		</tr>
		<tr>
			<td>Age&#160; (year)</td>
			<td>62</td>
			<td>52</td>
			<td>26</td>
		</tr>
		<tr>
			<td>Gender</td>
			<td>Male</td>
			<td>Male</td>
			<td>Male</td>
		</tr>
		<tr>
			<td>Body mass index (Kg/m2)</td>
			<td>20.5</td>
			<td>22.5</td>
			<td>17.4</td>
		</tr>
		<tr>
			<td>Disease duration (month)</td>
			<td>60</td>
			<td>24</td>
			<td>120</td>
		</tr>
		<tr>
			<td>Chicago classification</td>
			<td><img alt="Equation 1" src="/files/ftp_upload/63239/63239eq01.jpg" style="margin: auto;" /></td>
			<td><img alt="Equation 2" src="/files/ftp_upload/63239/63239eq02.jpg" style="margin: auto;" /></td>
			<td><img alt="Equation 3" src="/files/ftp_upload/63239/63239eq03.jpg" style="margin: auto;" /></td>
		</tr>
		<tr>
			<td>Sigmoid type</td>
			<td>No</td>
			<td>Yes</td>
			<td>No</td>
		</tr>
		<tr>
			<td>Previous therapy</td>
			<td>No</td>
			<td>No</td>
			<td>Pneumatic dilatation</td>
		</tr>
		<tr>
			<td>Length of myotomy (cm)</td>
			<td>9</td>
			<td>7</td>
			<td>8</td>
		</tr>
		<tr>
			<td>Esophageal</td>
			<td>6</td>
			<td>5</td>
			<td>6</td>
		</tr>
		<tr>
			<td>Gastric</td>
			<td>3</td>
			<td>2</td>
			<td>2</td>
		</tr>
		<tr>
			<td>Procedure time (min)</td>
			<td>60</td>
			<td>45</td>
			<td>40</td>
		</tr>
		<tr>
			<td>Hemostatic forceps usage</td>
			<td>No</td>
			<td>No</td>
			<td>No</td>
		</tr>
		<tr>
			<td>Length of postoperative hospital stay (day)</td>
			<td>3</td>
			<td>3</td>
			<td>3</td>
		</tr>
		<tr>
			<td>Perioperative adverse events</td>
			<td>No</td>
			<td>No</td>
			<td>No</td>
		</tr>
	</tbody>
</table>
Table 2: Details of patient characteristics and POEM procedures.
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Parameters</td>
			<td>Patient 1</td>
			<td>Patient 2</td>
			<td>Patient 3</td>
		</tr>
		<tr>
			<td>Weight gained (Kg)</td>
			<td>5.5</td>
			<td>4.5</td>
			<td>2.5</td>
		</tr>
		<tr>
			<td>Eckardt score</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Pre-POEM</td>
			<td>7</td>
			<td>8</td>
			<td>5</td>
		</tr>
		<tr>
			<td>Post-POEM</td>
			<td>0</td>
			<td>0</td>
			<td>1</td>
		</tr>
		<tr>
			<td>GerdQ score</td>
			<td>6</td>
			<td>6</td>
			<td>6</td>
		</tr>
		<tr>
			<td>Use of proton pump inhibitors</td>
			<td>No</td>
			<td>No</td>
			<td>No</td>
		</tr>
		<tr>
			<td>Lower esophageal sphincter pressure (mmHg)</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Pre-POEM</td>
			<td>47.6</td>
			<td>58.1</td>
			<td>42.5</td>
		</tr>
		<tr>
			<td>Post-POEM</td>
			<td>10.7</td>
			<td>23.5</td>
			<td>20.5</td>
		</tr>
		<tr>
			<td>4-second integrated relaxation pressure (mmHg)</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Pre-POEM</td>
			<td>39.0</td>
			<td>37.2</td>
			<td>42.4</td>
		</tr>
		<tr>
			<td>Post-POEM</td>
			<td>10.3</td>
			<td>13.0</td>
			<td>14.4</td>
		</tr>
		<tr>
			<td>Esophageal diameter on barium esophagram (cm)</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Pre-POEM</td>
			<td>3.7</td>
			<td>9.1</td>
			<td>7.5</td>
		</tr>
		<tr>
			<td>Post-POEM</td>
			<td>2.3</td>
			<td>2.9</td>
			<td>4.0</td>
		</tr>
		<tr>
			<td>Esophagitis on postoperative endoscopy</td>
			<td>LA-A</td>
			<td>No</td>
			<td>No</td>
		</tr>
	</tbody>
</table>
Table 3: Clinical outcomes of POEM using the scissor-type knife at 3-month follow-up.

Watch this Scientific Journal Video about Use of the Scissor-Type Knife During the Peroral Endoscopy Myotomy Procedure for the Treatment of Achalasia at JoVE.com

Use of the Scissor-Type Knife During the Peroral Endoscopy Myotomy Procedure for the Treatment of Achalasia

To minimize the technical difficulty and improve the safety of peroral endoscopic myotomy (POEM), we describe a protocol for using a scissor-type knife for the main steps of POEM, including mucosal incision, submucosal tunneling, myotomy, and hemostasis.

Peroral endoscopic myotomy (POEM) is one of the first-line treatment modalities along with pneumatic dilation and Heller myotomy for patients with ...

use-scissor-type-knife-during-peroral-endoscopy-myotomy-procedure-for

Universidad San Sebastian

Research

JoVE Journal

Medicine

3.0K Views.  The First Affiliated Hospital of Sun Yat-sen University. To minimize the technical difficulty and improve the safety of peroral endoscopic myotomy (POEM), we describe a protocol for using a scissor-type knife for the main steps of POEM, including mucosal incision, submucosal tunneling, myotomy, and hemostasis.

Video: Use of the Scissor-Type Knife During the Peroral Endoscopy Myotomy Procedure for the Treatment of Achalasia

ADSC-sheet Transplantation to Prevent Stricture after Extended Esophageal Endoscopic Submucosal Dissection

In past years, the cell-sheet construct has spurred wide interest in regenerative medicine, especially for reconstructive surgery procedures. The development of diversified technologies combining adipose tissue-derived stromal cells (ADSCs) with various biomaterials has led to the construction of numerous types of tissue-engineered substitutes, such as bone, cartilage, and adipose tissues from rodent, porcine, or human ADSCs. Extended esophageal endoscopic submucosal dissection (ESD) is responsible for esophageal stricture formation. Stricture prevention remains challenging, with no efficient treatments available. Previous studies reported the effectiveness of mucosal cell-sheet transplantation in a canine model and in humans. ADSCs are attributed anti-inflammatory properties, local immune modulating effects, neovascularization induction, and differentiation abilities into mesenchymal and non-mesenchymal lineages. This original study describes the endoscopic transplantation of an ADSC tissue-engineered construct to prevent esophageal stricture in a swine model. The ADSC construct was composed of two allogenic ADSC sheets layered upon each other on a paper support membrane. The ADSCs were labeled with the PKH67 fluorophore to allow probe-based confocal laser endomicroscopy (pCLE) monitoring. On the day of transplantation, a 5-cm and hemi-circumferential ESD known to induce esophageal stricture was performed. Animals were immediately endoscopically transplanted with 4 ADSC constructs. The complete adhesion of the ADSC constructs was obtained after 10 min of gentle application. Animals were sacrificed on day 28. All animals were successfully transplanted. Transplantation was confirmed on day 3 with a positive pCLE evaluation. Compared to transplanted animals, control animals developed severe strictures, with major fibrotic tissue development, more frequent alimentary trouble, and reduced weight gain. In our model, the transplantation of allogenic ADSCs, organized in double cell sheets, after extended ESD was successful and strongly associated with a lower esophageal stricture rate.

This study reports a successful method of endoscopical adipose tissue-derived stromal cell (ADSC)-sheet transplantation for esophageal stricture prevention after an extended endoscopic submucosal dissection (ESD) in a swine model.

In past years, the cell-sheet construct has spurred wide interest in regenerative medicine, especially for reconstructive surgery procedures. The ...

Autonomous and Rechargeable Microneurostimulator Endoscopically Implantable into the Submucosa

Gastric dysmotility can be a sign of common diseases such as longstanding diabetes mellitus. It is known that the application of high-frequency low-energetic stimulation can help to effectively moderate and alleviate the symptoms of gastric dysmotility. The goal of the research was the development of a miniature, endoscopically implantable device to a submucosal pocket. The implantable device is a fully customized electronic package which was specifically designed for the purpose of experiments in the submucosa. The device is equipped with a lithium-ion battery which can be recharged wirelessly by receiving an incident magnetic field from the charging/transmitting coil. The uplink communication is achieved in a MedRadio band at 432 MHz. The device was endoscopically inserted into the submucosal pocket of a live domestic pig used as an in vivo model, specifically in the stomach antrum. The experiment confirmed that the designed device can be implanted into the submucosa and is capable of bidirectional communication. The device can perform bipolar stimulation of muscle tissue.

The application of high-frequency low-energetic stimulation can alleviate the symptoms of gastric dysmotility. In this research, a miniature, endoscopically implantable and wirelessly rechargeable device which is implanted into a submucosal pocket is presented. Successful both-way communication and stimulation control were achieved during an experiment on live pig.

Gastric dysmotility can be a sign of common diseases such as longstanding diabetes mellitus. It is known that the application of high-frequency ...

Neuroscience

Endoscopic Approach for Studying Laryngeal Dysfunction in Rodents

Minimally Invasive Murine Laryngoscopy for Close&#45;Up Imaging of Laryngeal Motion During Breathing and Swallowing

The larynx is an essential organ in mammals with three primary functions - breathing, swallowing, and vocalizing. A wide range of disorders are known to impair laryngeal function, which results in difficulty&#160;breathing (dyspnea), swallowing impairment (dysphagia), and/or voice impairment (dysphonia). Dysphagia, in particular, can lead to aspiration pneumonia and associated morbidity, recurrent hospitalization, and early mortality. Despite these serious consequences, existing treatments for laryngeal dysfunction are largely aimed at surgical and behavioral interventions that unfortunately do not typically restore normal laryngeal function, thus highlighting the urgent need for innovative solutions.
To bridge this gap, we have been developing an experimental endoscopic approach to investigate laryngeal dysfunction in murine (i.e., mouse and rat) models. However, endoscopy in rodents is quite challenging due to their small size relative to current endoscope technology, anatomical differences in the upper airway, and the necessity for anesthesia to optimally access the larynx. Here, we describe a novel transoral laryngoscopy approach that permits close-up, unobstructed video imaging of laryngeal motion in mice and rats. Critical steps in the protocol include precise anesthesia management (to prevent overdosing that abolishes swallowing and/or risks respiratory distress-related mortality) and micromanipulator control of the endoscope (for stable video recording of laryngeal motion by a single researcher for subsequent quantification).
Importantly, the protocol can be performed over time in the same animals to study the impact of various pathological conditions specifically on laryngeal function. A novel advantage of this protocol is the ability to visualize airway protection during swallowing, which is not possible in humans due to epiglottic inversion over the laryngeal inlet that obstructs the glottis from view. Rodents therefore provide a unique opportunity to specifically investigate the mechanisms of normal versus pathological laryngeal airway protection for the ultimate purpose of discovering treatments to effectively restore normal laryngeal function.

This protocol describes a serial transoral laryngoscopy approach for mice and rats that permits close-up, unobstructed video imaging of the larynx during breathing and swallowing using an optimized anesthetic regimen and finely tuned endoscopic manipulation techniques.

The larynx is an essential organ in mammals with three primary functions - breathing, swallowing, and vocalizing. A wide range of disorders are known to ...

Clinical Application of Single-Surgeon, Three-Port, Laparoscopic Resection for Colorectal Cancer with Natural Orifice Specimen Extraction

Reduced-port laparoscopic surgery (RPLS) has been widely used for the radical resection of gastrointestinal tumors. Single-surgeon, three-port, laparoscopic radical resection for sigmoid colon or high rectal cancer with natural orifice specimen extraction surgery (NOSES) has the advantage of a small incision, quick postoperative recovery, and short hospital stay. Yet, there are still only a few reports on NOSES. This paper describes the indications, preoperative preparations, surgical steps, and precautions for single-surgeon, three-port, laparoscopic radical resection of the sigmoid colon and high rectal cancer, and intraoperative specimen collection through the natural orifice. 
The protocol focuses on the steps of radical dissection and the main technical points of resection and reconstruction. At the same time, a procedure for fixing an anvil seat by self-traction of extracorporeal silk thread, used for purse-string suture fixation after the proximal anvil was placed in the abdominal cavity, was creatively improved. This operation could effectively avoid problems such as an insufficient proximal intestinal tube, shaking off the anvil seat, and weak purse-string suture during a single operation. The surgical care had less variability and was easy to perform, effectively avoiding postoperative anastomotic leakage and bleeding due to excessive intraoperative anastomotic tissue. This surgery could be widely promoted in primary hospitals.

Here, we present a protocol to successfully perform single-surgeon, three-port, laparoscopic resection for colorectal cancer with natural orifice specimen extraction.

Reduced-port laparoscopic surgery (RPLS) has been widely used for the radical resection of gastrointestinal tumors. Single-surgeon, three-port, ...

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.

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 ...

Surgical Treatment of Gastroparesis

Gastroparesis and intestinal dysmotility are life-altering diagnoses with no cure. Lifestyle changes, pharmacological, and surgical interventions are combined in a multidisciplinary fashion to improve the quality of life in this patient population. Starting with lifestyle changes, adjustments are made to the types and amounts of food consumed, medical conditions are optimized, and the use of narcotic pain medications as well as smoking is discontinued. For many, these changes are not enough, and antiemetics and promotility agents are used to control symptoms. Finally, when these measures fail, patients turn to surgery, which can include surgical alterations to the stomach, implantation of a gastric stimulator, placement of drainage tubes, and possibly even the complete removal of different organs, including the stomach or gallbladder. In our clinic, patients not only see a surgeon but also a gastroenterologist, dietitian, and psychologist. We strongly believe in a multidisciplinary approach to this condition. The goal is to provide patients with hope and help them live fuller and happier lives.
The study primarily addresses technical considerations and the surgical approach for patients diagnosed with gastroparesis. It outlines the entire process, starting from preparations before the surgery, encompassing the preoperative work-up, and detailing the steps involved in the surgical procedure. One of the key diagnostic challenges faced in treating gastroparesis patients is determining the underlying cause of the condition, as this information is critical for selecting the appropriate surgical intervention. Once the patient&#39;s condition has been categorized based on the cause, the medical team engages in a discussion with the patient regarding potential treatment options, which may include endoscopic procedures, minimally invasive techniques, or open surgery.

Gastroparesis is a condition in which the stomach does not empty properly. While it is initially managed with lifestyle modifications and medications, some patients eventually require surgical intervention. This study focuses on the technical considerations and surgical approaches for dealing with gastroparesis patients, which include endoscopic, minimally-invasive, and open surgical techniques.

Gastroparesis and intestinal dysmotility are life-altering diagnoses with no cure. Lifestyle changes, pharmacological, and surgical interventions are ...

Treatment of Achalasia by Robot-Assisted Heller Myotomy

Robotic Heller Myotomy for Advancements in Surgical Management of Achalasia

Achalasia is an esophageal motility disorder. It occurs due to the destruction of nerves in the lower esophageal sphincter (LES), which leads to the failure of the LES to relax. Patients typically complain of dysphagia, chest pain, and regurgitation. They often report drinking liquids with solids intake to help propel food boluses into the stomach. The diagnosis of achalasia is typically confirmed with an esophagogram and a motility study (esophageal manometry). An esophagogram classically shows the bird beak sign with tapering in the distal esophagus. The treatment for achalasia includes both surgical and non-surgical options. Surgical treatment is associated with a lower rate of recurrences, high clinical success rate, and durability of symptom relief. The current gold standard of surgical technique is myotomy, or the dividing of the muscle fibers of the distal esophagus. Surgical myotomy can be accomplished via a laparoscopic or robotic technique; per-oral endoscopic myotomy is a new alternative intervention. Due to the theoretical risk of gastroesophageal reflux following a myotomy, an antireflux procedure is sometimes performed. We reviewed the approach to a robotic heller myotomy for the treatment of achalasia.

Author Spotlight: Cutting-Edge Robotic Heller Myotomy Protocol for Treatment of Achalasia

The protocol presents a robotic approach to Heller myotomy for the treatment of achalasia.

Achalasia is an esophageal motility disorder. It occurs due to the destruction of nerves in the lower esophageal sphincter (LES), which leads to the ...

Single Incision Plus One Port Laparoscopic Proximal Gastrectomy with Double Channel Anastomosis for Gastric Cancer Treatment

Single-incision plus one-port laparoscopic proximal gastrectomy with double-channel anastomosis (SILT-DT) is a minimally invasive surgical approach for treating proximal gastric cancer. This technique includes comprehensive laparoscopic resection of the proximal stomach, lymph node dissection, and double-tract anastomosis. By integrating single-port laparoscopic surgery with an auxiliary operating hole, SILT-DT reduces procedural difficulty while facilitating the placement of an abdominal drainage tube. Compared to the traditional five-port laparoscopic gastrectomy, SILT-DT requires fewer ports and results in shorter incision lengths, contributing to reduced postoperative pain and faster recovery. A thorough preoperative evaluation was conducted to ensure procedural success, with factors such as tumor size, stage, location, and patient BMI carefully considered. This comprehensive assessment allowed for optimal patient selection and surgical planning. Postoperative follow-up demonstrated no significant complications, underscoring the safety and efficacy of SILT-DT. This innovative technique offers a promising minimally invasive alternative for managing proximal gastric cancer while maintaining excellent clinical outcomes.

The single-incision plus one-port laparoscopic proximal gastrectomy with double-channel anastomosis was initially employed for the radical resection of proximal gastric cancer. This study demonstrated the feasibility of the procedure and laid a foundation for further research.

Single-incision plus one-port laparoscopic proximal gastrectomy with double-channel anastomosis (SILT-DT) is a minimally invasive surgical approach for ...

Laparoscopic Choledochal Cyst Excision and Roux-en-Y Choledochojejunostomy in Adults

Choledochal cysts (CCs), known as congenital choledochal dilatations, are more prevalent in Asia. The majority of patients with abdominal symptoms are diagnosed and treated during early childhood, which results in a lower prevalence of CCs in adults. The treatment of choice for CCs is complete cyst excision followed by choledochojejunostomy. Laparoscopic surgery is now more widely accepted than traditional open surgery due to its smaller incisions, faster recovery, and less postoperative pain. However, there are few reports on laparoscopic excision of CCs in adults. This article presents a protocol that describes and demonstrates the complete procedure for laparoscopic excision of a choledochal cyst and Roux-en-Y choledochojejunostomy. A 32-year-old woman diagnosed with a 2.5 cm by 3 cm CC underwent surgery using a laparoscopic approach with post-colonic anastomosis. The procedure lasted 290 min with an estimated blood loss of approximately 100 mL. A follow-up abdominal CT scan on the sixth postoperative day showed a satisfactory recovery, leading to her discharge on the ninth day. This study aims to demonstrate the feasibility and safety of laparoscopically assisted excision of CCs in adults. This procedure is expected to become the preferred surgical option for CCs in adults due to its minimal surgical trauma and rapid postoperative recovery.

Choledochal cysts in adults are relatively rare, and few reports have detailed treatment options. Here, we present a case demonstrating laparoscopic resection of choledochal cysts and posterior colonic Roux-en-Y choledochojejunostomy in adults, offering an alternative for clinical management.

Choledochal cysts (CCs), known as congenital choledochal dilatations, are more prevalent in Asia. The majority of patients with abdominal symptoms are ...

Endoscope-assisted Anterior Cervical Discectomy and Fusion for the Treatment of Cervical Spondylotic Myelopathy

Cervical spondylotic myelopathy (CSM) is a common cause of cervical spinal cord disease. Spinal endoscopy offers surgical advantages such as a magnified view and a water-mediated clear surgical field. This study describes an endoscope-assisted anterior cervical discectomy and fusion (ACDF) procedure. The addition of spinal endoscopy to traditional ACDF surgery magnifies the surgical field and allows for more precise operations, thereby improving surgical safety. Postoperatively, patients experienced significant improvements in neurological function, with no complications such as dysphagia, hematoma, or spinal cord injury. Postoperative imaging revealed that spinal cord compression was completely relieved, with sufficient decompression of the spinal cord and optimal placement of the fusion cage. The clear visual field provided by spinal endoscopy improves the identification of cervical anatomical structures during surgery, effectively reducing the risk of injury to the spinal cord and nerves. Endoscope-assisted ACDF has demonstrated excellent clinical and radiological outcomes in the treatment of CSM.

We describe a minimally invasive surgery using Endoscope-assisted Anterior Cervical Discectomy and Fusion for the Cervical Spondylotic Myelopathy.

Cervical spondylotic myelopathy (CSM) is a common cause of cervical spinal cord disease. Spinal endoscopy offers surgical advantages such as a magnified ...