The authors would like to thank the West China Second University Hospital of Sichuan University for providing cases and medical records related to this work. There is no funding support for this study.

The surgical method described in this paper has been approved by the Ethics Committee of the West China Second University Hospital of Sichuan University, and the use of patient surgical videos has been authorized. Informed consent was obtained from the patients, and their data was used for presentation. The consumables and equipment used for this study are listed in the Table of Materials.
1. Preparation for operation
<ol>
	<li>Use the following inclusion criteria to select participants for the study:
	<ol>
		<li>Adult males who have opted for sterilization.</li>
		<li>Ensure preoperative color Doppler ultrasonography11 reveals normal bilateral vas deferens development in the patients.</li>
		<li>Exclude any individuals with diseases that could affect the safety of the surgery, such as poorly controlled hypertension, hyperglycemia, or respiratory diseases.</li>
	</ol>
	</li>
	<li>Apply the following exclusion criteria to exclude participants from the study:
	<ol>
		<li>Exclude patients with severe coagulopathy or other contraindications to anesthesia.</li>
	</ol>
	</li>
	<li>Perform skin preparation before surgery.</li>
</ol>
2. Surgical procedure
<ol>
	<li>Stand on the right side of the patient and perform bilateral spermatic nerve blocks using 2% lidocaine. Apply pressure for 1 min to stop bleeding and reduce local edema.</li>
	<li>Use the three-finger technique6 to fix the right vas deferens beneath the median raphe. Firmly trap the vas deferens under the thumb and index finger of the left hand and over the middle finger for fixation.</li>
	<li>Flatten the scrotal skin over the vas deferens, and clamp the vas deferens using an extracutaneous vas deferens fixation ring clamp with the right hand.</li>
	<li>Maintain the ring clamp in a clamped state and pass it from the right hand to the left. Secure the ring clamp with the left thumb, middle, and ring fingers.</li>
	<li>Press the scrotal skin downward with the left index finger while simultaneously elevating the ring clamp to tighten the skin over the vas deferens using the left thumb, middle, and ring fingers.</li>
	<li>Use one blade of the dissecting clamp to puncture the skin and vas sheath, then withdraw the dissecting clamp.</li>
	<li>Close both blades of the dissecting clamp and reinsert it through the same puncture hole. Gently open the clamp to separate the scrotal skin by about 1 cm.</li>
	<li>Use the right blade of the dissecting clamp to pierce the most superficial and prominent part of the vas deferens wall. Rotate the dissecting clamp 180 degrees laterally.</li>
	<li>Release the extracutaneous vas deferens fixation ring clamp with the left hand. Elevate the dissecting clamp and extract the right vas deferens from the body.</li>
	<li>Grasp the delivered vas deferens with the ring clamp using the left hand. Gently isolate the right vas deferens artery with the dissecting clamp, exposing a clean segment of about 2.5 cm.</li>
	<li>Pull the ring clamp toward the abdominal side and straighten the vas deferens. Use a 3-0 silk suture to complete the first ligation at the testicular end of the vas deferens.</li>
	<li>Pull the ring clamp toward the testicular side and perform a second ligation on the abdominal side, 1.5 cm from the first ligation.</li>
	<li>Tighten the suture tails of the first ligation toward the testicular side and pull the ring clamp toward the abdominal side. 
	NOTE: The bare vas deferens should now be clearly visible.</li>
	<li>Use the dissecting clamp to clamp the right vas deferens 1 cm from the first ligation on the abdominal side. Release the extracutaneous vas deferens fixation ring clamp.</li>
	<li>Complete a third ligation between the dissecting clamp and the first ligation. Transect the right vas deferens tightly against the abdominal side of the dissecting clamp.</li>
	<li>Rotate the dissecting clamp 180 degrees and pull the tails of the second ligation toward the testicular side over the dissecting clamp and the first ligation.</li>
	<li>Perform a fourth ligation on the abdominal side of the right vas deferens, 1 cm from the second ligation, using the suture tails from the third ligature.</li>
	<li>Pull the suture tails of the second ligation toward the testicular side and those of the fourth ligation toward the abdominal side. Perform a fifth ligation between the second and fourth ligations using the suture tails from the first ligation (Figure 1).</li>
	<li>Ensure there is no bleeding in the surgical area. Cut off the ends of the three sutures.</li>
	<li>Pull the right testis toward the testicular side through the scrotum, and reposition the right vas deferens with the anatomical reduction in the scrotum.</li>
	<li>Repeat the procedure on the left vas deferens and suture the scrotal incision with 5-0 absorbable sutures.</li>
</ol>
3. Postoperative care and follow-up
<ol>
	<li>Change the dressing every 3 days after surgery, and remove the sutures 1 week later.</li>
	<li>Instruct patients to refrain from ejaculation for approximately 2 weeks after the vasectomy.</li>
	<li>After 2 weeks, advise them to ejaculate regularly, twice a week. Perform post-vasectomy semen analysis (PVSA) after 20 ejaculations12.</li>
</ol>
4. Statistical analysis
<ol>
	<li>Analyze all data statistically using statistical data analysis software.</li>
	<li>Use a t-test for data conforming to a normal distribution and a non-parametric test for data not conforming to a normal distribution. Consider statistical differences significant when P &#60; 0.05.</li>
	<li>Present results as mean &#177; SD for data conforming to a normal distribution and as medians with interquartile ranges for data not conforming to a normal distribution.</li>
</ol>

Bilateral Spermatic Nerve Blocks and Vasectomy Procedures in Males

<ol>
	<li>Rayala, B. Z., Viera, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Common+questions+about+vasectomy.">Common questions about vasectomy.</a> Am Fam Physician. 88 (11), 757-761 (2013).</li><li>Dassow, P., Bennett, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vasectomy:+An+update.">Vasectomy: An update.</a> Am Fam Physician. 74 (12), 2069-2074 (2006).</li><li>Fainberg, J., Kashanian, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+vasectomy+is+a+surgical+sterilization+procedure+for+men+to+prevent+future+fertility.">A vasectomy is a surgical sterilization procedure for men to prevent future fertility.</a> JAMA. 319 (23), 2450 (2018).</li><li>Velez, D., Pagani, R., Mima, M., Ohlander, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vasectomy:+A+guidelines-based+approach+to+male+surgical+contraception.">Vasectomy: A guidelines-based approach to male surgical contraception.</a> Fertil Steril. 115 (6), 1365-1368 (2021).</li><li>Ostrowski, K. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+vasectomy+trends+in+the+United+States.">Evaluation of vasectomy trends in the United States.</a> Urology. 118, 76-79 (2018).</li><li>Li, S., Goldstein, M., Zhu, J., Huber, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+no-scalpel+vasectomy.">The no-scalpel vasectomy.</a> J Urol. 145 (2), 341-344 (1991).</li><li>Sharlip, I. D., 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=Vasectomy:+Aua+guideline.">Vasectomy: Aua guideline.</a> J Urol. 188 (6S), 2482-2491 (2012).</li><li>Barone, M. A., Irsula, B., Chen-Mok, M., Sokal, D. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effectiveness+of+vasectomy+using+cautery.">Effectiveness of vasectomy using cautery.</a> BMC Urol. 4 (1), (2004).</li><li>Black, T., Francome, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+evolution+of+the+Marie+Stopes+electrocautery+no-scalpel+vasectomy+procedure.">The evolution of the Marie Stopes electrocautery no-scalpel vasectomy procedure.</a> J Fam Plann Reprod Health Care. 28 (3), 137-138 (2002).</li><li>Dohle, G. R., 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=European+association+of+urology+guidelines+on+vasectomy.">European association of urology guidelines on vasectomy.</a> Eur Urol. 61 (1), 159-163 (2012).</li><li>Osama, 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=Duplication+of+the+vas+deferens:+A+rare+anomaly.">Duplication of the vas deferens: A rare anomaly.</a> Ochsner J. 21 (1), 108-110 (2021).</li><li>Griffin, T., Tooher, R., Nowakowski, K., Lloyd, M., Maddern, G. U. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=How+little+is+enough?+The+evidence+for+post-vasectomy+testing.">How little is enough? The evidence for post-vasectomy testing.</a> J Urol. 174 (1), 29-36 (2005).</li><li>Art, K. S., Nangia, A. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Techniques+of+vasectomy.">Techniques of vasectomy.</a> Urol Clin North Am. 36 (3), 307-316 (2009).</li><li>Rogers, M. D., Kolettis, P. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vasectomy.">Vasectomy.</a> Urol Clin North Am. 40 (4), 559-568 (2013).</li><li>Weiske, W. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vasectomy.">Vasectomy.</a> Andrologia. 33 (3), 125-134 (2001).</li><li>Seth, I., 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=Vasovasostomy:+A+systematic+review+and+meta-analysis+comparing+macroscopic,+microsurgical,+and+robot-assisted+microsurgical+techniques.">Vasovasostomy: A systematic review and meta-analysis comparing macroscopic, microsurgical, and robot-assisted microsurgical techniques.</a> Andrology. 12 (4), 740-767 (2024).</li></ol>

The authors declare that they have no competing interests.

The gold standard for vasectomy is ligation with mucosal cautery13, but not all operating rooms have electrocautery equipment. Therefore, this modification technique achieved ideal surgical results by ligating the vas deferens five times with non-absorbable silk sutures, without the need for electrocautery equipment. It has been documented that applying excessive pressure to the vas with sutures can create ischemia and sloughing of the ligated stump, leading to recanalization. This may explain som...

Vasectomy is a surgical sterilization procedure for men to prevent future fertility1,2,3. It is equally effective as tubal ligation for preventing pregnancy but is simpler, safer, faster, and less expensive4. This type of surgery has lower implementation requirements, and more than 80% of vasectomies are performed in the office5. Since 1971, when Li Shunqiang et al. performed the first modified vasectomy (the no-scalpel vasectomy or NSV)6, the procedure has advanced significantly. The invention of the extracutaneous vas deferens fixation ring clamp has reduced the number of surgical steps, while simultaneously minimizing surgical damage and the difficulty of the procedure1. As a result, NSV has become the mainstream surgical method for vasectomy.
However, NSV still uses a single ligation and transection to seal the bilateral vas deferens ends, and the postoperative recanalization rate remains high. It has been reported that the occlusive failure rate after simple vasectomy is around 13.79%, and the postoperative recanalization rate is still 5.85% after vasectomy and fascial interposition7. As such, andrologists continue to explore improvements to vasectomy. Literature reports indicate that the postoperative recanalization rate can be reduced to 1% by using mucosal cautery on the ligated stumps8. Additionally, non-divisional vasectomy with extended electrocautery can further reduce the postoperative recanalization rate to 0.64%9.
However, for medical institutions lacking electrocautery equipment, reducing the postoperative recanalization rate remains a challenge. Therefore, the new technique proposes performing five ligations of the vas deferens without electrocautery conditions, building on the NSV method to reduce the postoperative recanalization rate. After five ligations, the formation of a vas deferens ischemic zone greater than 1 cm in length can increase the difficulty of vas deferens recanalization. This modified technique is also advantageous for exploring the ends of the vas deferens during future vasovasostomy. Compared to previous reports10, this modification does not require electrocautery equipment during surgery, thereby reducing equipment requirements. This approach can help operating rooms without electrocautery equipment to perform a vasectomy.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>3-0 silk braided non-absorbable suture</td>
			<td>Johnson &#38; Johnson Medical (China) Ltd.</td>
			<td>SA84G</td>
			<td>15 &#215; 60cm</td>
		</tr>
		<tr>
			<td>5-0 Coated VICRYL Plus (Polyglactin 910) Synthetic Absorbable Suture</td>
			<td>Ethicon.Inc.</td>
			<td>VCP433H</td>
			<td>13 mm 1/2c (70cm)</td>
		</tr>
		<tr>
			<td>Dissecting clamp</td>
			<td>Xinhua Surgical Instruments Co., Ltd.</td>
			<td>ZJ197R</td>
			<td>125 mm</td>
		</tr>
		<tr>
			<td>Extracutaneous vas deferens fixation ring clamp</td>
			<td>Xinhua Surgical Instruments Co., Ltd.</td>
			<td>ZJ196R</td>
			<td>140 mm</td>
		</tr>
		<tr>
			<td>Scissors</td>
			<td>Xinhua Surgical Instruments Co., Ltd.</td>
			<td>ZC344R</td>
			<td>140 mm</td>
		</tr>
		<tr>
			<td>SPSS 23.0</td>
			<td>IBM</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

optimizing the modified no-scalpel vasectomy technique

No-scalpel vasectomy (NSV) is a commonly used contraceptive method for males. In previous applications of this surgical method, issues such as knot detachment and postoperative recanalization resulted in a reduced contraceptive success rate after vasectomy. This new technique innovatively modifies the ligation procedure during NSV to address knot detachment and postoperative recanalization. Two ligations of the testicular end of the vas deferens and one ligation of the abdominal end are completed before transection of the vas deferens. A fourth ligation of the abdominal end is performed using the suture tails of the third ligature of the testicular end after transection of the vas deferens. The fifth ligation of the abdominal end is performed using the suture tails of the first ligature of the testicular end. These modifications strengthen the ligations and reduce the postoperative recanalization rate. Additionally, the two stumps are gathered together, creating better conditions for a possible vasovasostomy in the future, thereby achieving overall better outcomes with vasectomy.

From January 2021 to August 2023, 58 vasectomies were performed at this hospital. All 58 patients had at least one child with their spouses before undergoing vasectomy. Although the modification involved more surgical steps compared to NSV, it did not significantly increase the difficulty of the operations. As a result, all 58 vasectomies were successfully completed without any unsuccessful operations. Patients were followed up regularly by telephone. Follow-up ended when the PVSA demonstrated less than 2,00,000 sperm/mL...

Optimizing the Modified No-Scalpel Vasectomy Technique

A modified no-scalpel vasectomy technique reduces the postoperative recanalization rate. This protocol describes a modified no-scalpel vasectomy technique that can reduce the postoperative recanalization rate.

No-scalpel vasectomy (NSV) is a commonly used contraceptive method for males. In previous applications of this surgical method, issues such as knot ...

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164 Views.  Sichuan University. A modified no-scalpel vasectomy technique reduces the postoperative recanalization rate. This protocol describes a modified no-scalpel vasectomy technique that can reduce the postoperative recanalization rate.

Video: Optimizing the Modified No-Scalpel Vasectomy Technique

Modified Technique for Coronary Artery Ligation in Mice

Myocardial infarction (MI) is one of the most important causes of mortality in humans1-3. In order to improve morbidity and mortality in patients with MI we need better knowledge about pathophysiology of myocardial ischemia. This knowledge may be valuable to define new therapeutic targets for innovative cardiovascular therapies4. Experimental MI model in mice is an increasingly popular small-animal model in preclinical research in which MI is induced by means of permanent or temporary ligation of left coronary artery (LCA)5. In this video, we describe the step-by-step method of how to induce experimental MI in mice.
The animal is first anesthetized with 2% isoflurane. The unconscious mouse is then intubated and connected to a ventilator for artificial ventilation. The left chest is shaved and 1.5 cm incision along mid-axillary line is made in the skin. The left pectoralis major muscle is bluntly dissociated until the ribs are exposed. The muscle layers are pulled aside and fixed with an eyelid-retractor. After these preparations, left thoracotomy is performed between the third and fourth ribs in order to visualize the anterior surface of the heart and left lung. The proximal segment of LCA artery is then ligated with a 7-0 ethilon suture which typically induces an infarct size ~40% of left ventricle. At the end, the chest is closed and the animals receive postoperative analgesia (Temgesic, 0.3 mg/50 ml, ip). The animals are kept in a warm cage until spontaneous recovery.

The surgical procedure used to induce experimental myocardial infarction in mice begins with left thoracotomy between the third and the fourth ribs in order to visualize the anterior surface of the heart and left lung. The left coronary artery is ligated, the chest is closed and the mouse is allowed to recover spontaneously.

Myocardial infarction (MI) is one of the most important causes of mortality in humans1-3. In order to improve morbidity and mortality in patients with MI ...

Murine Cervical Heart Transplantation Model Using a Modified Cuff Technique

Mouse models are of special interest in research since a wide variety of monoclonal antibodies and commercially defined inbred and knockout strains are available to perform mechanistic in vivo studies. While heart transplantation models using a suture technique were first successfully developed in rats, the translation into an equally widespread used murine equivalent was never achieved due the technical complexity of the microsurgical procedure. In contrast, non-suture cuff techniques, also developed initially in rats, were successfully adapted for use in mice1-3. This technique for revascularization involves two major steps I) everting the recipient vessel over a polyethylene cuff; II) pulling the donor vessel over the formerly everted recipient vessel and holding it in place with a circumferential tie. This ensures a continuity of the endothelial layer, short operating time and very high patency rates4.
Using this technique for vascular anastomosis we performed more than 1,000 cervical heart transplants with an overall success rate of 95%. For arterial inflow the common carotid artery and the proximal aortic arch were anastomosed resulting in a retrograde perfusion of the transplanted heart. For venous drainage the pulmonary artery of the graft was anastomosed with the external jugular vein of the recipient5.
Herein, we provide additional details of this technique to supplement the video.

The murine cervical heart transplantation model is well suited for immunological as well as ischemia reperfusion injury studies. We modified the procedure using a non-suture cuff technique and performed more than 1,000 successful transplants with this approach.
Herein, we provide additional details of this technique to supplement the video.

Mouse models are of special interest in research since a wide variety of monoclonal antibodies and commercially defined inbred and knockout strains are ...

Human Skeletal Muscle Biopsy Procedures Using the Modified Bergstr&#246;m Technique

The percutaneous biopsy technique enables researchers and clinicians to collect skeletal muscle tissue samples. The technique is safe and highly effective. This video describes the percutaneous biopsy technique using a modified Bergstr&#246;m needle to obtain skeletal muscle tissue samples from the vastus lateralis of human subjects. The Bergstr&#246;m needle consists of an outer cannula with a small opening (&#8216;window&#8217;) at the side of the tip and an inner trocar with a cutting blade at the distal end. Under local anesthesia and aseptic conditions, the needle is advanced into the skeletal muscle through an incision in the skin, subcutaneous tissue, and fascia. Next, suction is applied to the inner trocar, the outer trocar is pulled back, skeletal muscle tissue is drawn into the window of the outer cannula by the suction, and the inner trocar is rapidly closed, thus cutting or clipping the skeletal muscle tissue sample. The needle is rotated 90&#176;&#160;and another cut is made. This process may be repeated three more times. This multiple cutting technique typically produces a sample of 100-200 mg or more in healthy subjects and can be done immediately before, during, and after a bout of exercise or other intervention. Following post-biopsy dressing of the incision site, subjects typically resume their activities of daily living right away and can fully participate in vigorous physical activity within 48-72 hr. Subjects should avoid heavy resistance exercise for 48 hr to reduce the risk of herniation of the muscle through the incision in the fascia.

The purpose of this video is to present the modified Bergstr&#246;m skeletal muscle biopsy technique on human subjects.

The percutaneous biopsy technique enables researchers and clinicians to collect skeletal muscle tissue samples. The technique is safe and highly ...

Mouse Model for Pancreas Transplantation Using a Modified Cuff Technique

Mouse models have several advantages in transplantation research, including easy handling, a variety of genetically well-defined strains, and the availability of the widest range of molecular probes and reagents to perform in vivo as well as in vitro studies. Based on our experience with various murine transplantation models, we developed a heterotopic pancreas transplantation model in mice with the intent to analyze mechanisms underlying severe ischemia reperfusion injury-associated early graft damage. In contrast to previously described techniques using suture techniques, herein we describe a new procedure using a non-suture cuff technique. 
In recent years, we have performed more than 300 pancreas transplantations in mice with an overall success rate of &gt;90%, a success rate never described before in mouse pancreas transplantation. The backbone of this non-suture cuff technique for graft revascularization consists of two major steps: (I) pulling the recipient vessel over a polyethylene/polyamide cuff and fixing it with a circumferential ligature, and (II) placing the donor vessel over the everted recipient vessel and fixing it with a second circumferential ligature. The resultant continuity of the endothelial layer results in less thrombogenic lesions with high patency rates and, finally, high success rates.
In this model, arterial anastomosis is achieved by pulling the abdominal aorta of the donor graft over the everted common carotid artery of the recipient animal. Venous drainage of the graft is achieved by pulling the portal vein of the graft over the everted external jugular vein of the recipient. This manuscript provides details and crucial steps of the organ recovery and organ implantation procedures, which will allow researchers with microsurgical skills to perform the transplantation successfully in their laboratories.

Among abdominal solid organ transplantation, pancreatic grafts are prone to develop severe ischemia reperfusion injury-associated graft damage, leading eventually to early graft loss. This protocol describes a model of murine pancreas transplantation using a non-suture cuff technique, ideally suited for analyzing these early, deleterious damages.

Mouse models have several advantages in transplantation research, including easy handling, a variety of genetically well-defined strains, and the ...

Murine Cervical Aortic Transplantation Model using a Modified Non-Suture Cuff Technique

With the introduction of powerful immunosuppressive protocols, distinct advances are possible in the prevention and therapy of acute rejection episodes. However, only minor improvement in the long-term results of transplanted solid organs could be observed over the past decades. In this context, chronic allograft vasculopathy (CAV) still represents the leading cause of late organ failure in cardiac, renal and pulmonary transplantation.
Thus far, the underlying pathogenesis of CAV development remains unclear, explaining why effective treatment strategies are presently missing and emphasizing a need for relevant experimental models in order to study the underlying pathophysiology leading to CAV formation. The following protocol describes a murine heterotopic cervical aortic transplantation model using a modified non-suture cuff technique. In this technique, a segment of the thoracic aorta is interpositioned in the right common carotid artery. With the use of the non-suture cuff technique, an easy to learn and reproducible model can be established, minimizing the possible heterogeneity of sutured vascular micro anastomoses.

Here, we present a protocol of heterotopic aortic transplantation in mice using the non-suture cuff technique in a cervical murine model. This model can be used to study the underlying pathology of chronic allograft vasculopathy (CAV) and can help evaluate new therapeutic agents in order to prevent its formation.

With the introduction of powerful immunosuppressive protocols, distinct advances are possible in the prevention and therapy of acute rejection episodes. ...

Creating Radio-cephalic Arteriovenous Fistula in the Forearm with a Modified No-Touch Technique

Autologous arteriovenous fistula (AVF) is the primary and best option to obtain vascular access for hemodialysis treatment; other options are arteriovenous graft (AVG) and central venous catheterization (CVC). The implementation of radio-cephalic autologous arteriovenous fistula (RC-AVF) in the forearm was preferred among patients with superior vascular conditions. However, there is a high rate of early fistula failure. The chosen surgical method is understood to have an effect on the maturation of the fistula. New surgical procedures such as radial artery deviation and reimplantation (RADAR) have been significantly improved for juxta-anastomotic stenosis. Nevertheless, new problems such as stenosis of arteries and narrowing of surgical indication were also found. In this report, we presented a modified no-touch technique (MNTT) to create an RC-AVF, in which the venous and arterial wall avoid devascularization and the radial artery does not sever.

We present a modified no-touch technique (MNTT) to create a radio-cephalic arteriovenous fistula (RC-AVF) in which the venous and arterial wall avoid devascularization and the radial artery does not sever.

Autologous arteriovenous fistula (AVF) is the primary and best option to obtain vascular access for hemodialysis treatment; other options are ...

A Modified Simple Method for Induction of Myocardial Infarction in Mice

Myocardial infarction (MI) represents one of the leading causes of death. MI models are widely used for investigating the pathomechanisms of post-MI remodeling and evaluation of novel therapeutics. Different methods (e.g., isoproterenol treatment, cryoinjury, coronary artery ligation, etc.) have been used to induce MI. Compared with isoproterenol treatment and cryoinjury, coronary artery ligation may better reflect the ischemic response and chronic remodeling after MI. However, traditional methods for coronary ligation in mice are technically challenging. The current study describes a simple and efficient process for induction of MI in mice with readily available materials. The mouse chest skin was cut open under stable anesthesia. The heart was immediately externalized through the intercostal space after blunt separation of the pectoralis major and pectoralis minor. The left anterior descending branch (LAD) was ligated with a 6-0 suture 3 mm from its origin. Following LAD ligation, staining with 2,3,5-Triphenyltetrazolium chloride (TTC) indicated successful induction of MI and temporal changes of post-MI scar size. Meanwhile, survival analysis results showed overt mortality within 7 days after MI, mainly due to cardiac rupture. Moreover, post-MI echocardiographic assessment demonstrated successful induction of contractile dysfunction and ventricular remodeling. Once mastered, an MI model can be established in mice within 2-3 min with readily available materials.

Under adequate anesthesia, the mouse heart was externalized through the intercostal space, and myocardial infarction was successfully induced by ligating the left anterior descending artery (LAD) using materials readily available in most laboratories.

Myocardial infarction (MI) represents one of the leading causes of death. MI models are widely used for investigating the pathomechanisms of post-MI ...

Modified Technique for the Use of Neonatal Murine Hearts in the Langendorff Preparation

The use of the ex-vivo retrograde perfused heart has long been a cornerstone of ischemia-reperfusion investigation since its development by Oskar Langendorff over a century ago. Although this technique has been applied to mice over the last 25 years, its use in this species has been limited to adult animals. Development of a successful method to consistently cannulate the neonatal murine aorta would allow for the systematic study of the isolated retrograde perfused heart during a critical period of cardiac development in a genetically modifiable and low-cost species. Modification of the Langendorff preparation enables cannulation and establishment of reperfusion in the neonatal murine heart while minimizing ischemic time. Optimization requires a two-person technique to permit successful cannulation of the newborn mouse aorta using a dissecting microscope and a modified commercially available needle. The use of this approach will reliably establish retrograde perfusion within 3 min. Because the fragility of the neonatal mouse heart and ventricular cavity size prevents direct measurement of intraventricular pressure generated using a balloon, use of a force transducer connected by a suture to the apex of the left ventricle to quantify longitudinal contractile tension is necessary. This method allows investigators to successfully establish an isolated constant-flow retrograde-perfused newborn murine heart preparation, permitting the study of developmental cardiac biology in an ex-vivo manner. Importantly, this model will be a powerful tool to investigate the physiological and pharmacological responses to ischemia-reperfusion in the neonatal heart.

The present protocol describes aortic cannulation and retrograde perfusion of the ex-vivo neonatal murine heart. A two-person strategy, using a dissecting microscope and a blunted small gauge needle, permits reliable cannulation. Quantification of longitudinal contractile tension is achieved using a force transducer connected to the apex of the left ventricle.

The use of the ex-vivo retrograde perfused heart has long been a cornerstone of ischemia-reperfusion investigation since its development by Oskar ...

A Modified Cuff Technique for Mouse Cervical Heterotopic Heart Transplantation Model

Cardiac allograft rejection limits the long-term survival of patients after heart transplantation. A mouse heart transplantation model is ideal for investigating the mechanism of cardiac allograft rejection in preclinical studies because of their high homology with human genes. This understanding would help develop unique approaches to improving patients&#39; long-term survival treated with cardiac allografts. In a mouse model, abdominal donor heart implantation is commonly performed with an end-to-end&#160;anastomosis to the recipient&#39;s aorta and inferior vena cava using stitches. In this model, the donor&#39;s heart is implanted by end-to-end anastomosis to the recipient&#39;s carotid artery and jugular vein by the modified-Cuff technique. The transplantation surgery is performed without stitching and thus may increase the survival of the recipient since there is no interference with the blood supply and venous reflux of the lower body. This mouse model would help investigate the mechanisms underlying the immunological and pathological (acute/chronic) rejection of cardiac allografts.

In the present protocol, a mouse heart transplantation model is used for investigating the mechanism of cardiac allograft rejection. In this heterotopic heart transplantation model, operation efficiency is improved, and the survival of cardiac grafts is ensured by a cervical end-to-end anastomosis of heart implantation using a modified Cuff technique.

Cardiac allograft rejection limits the long-term survival of patients after heart transplantation. A mouse heart transplantation model is ideal for ...

A Modified Vessel-Sparing Microsurgical Vasoepididymostomy

Microsurgical vasoepididymostomy (MVE) is the main surgical treatment for epididymal obstruction. The vasal vessels are ligated during MVE. However, preserving the vasal vessels during MVE might better simulate the normal physiological structure and be meaningful for patients who have undergone varicocelectomy. Nevertheless, preserving the vasal vessels might elevate the risk of increasing the tension of anastomosis, affecting the patency rate and leading to delayed postoperative bleeding. Therefore, we developed a novel vessel-sparing MVE to make it safer. Here is a summary of the improvements to the procedure. 1) The retrograde dissociation of the vasal vessels on the proximal testicular side was adopted as the main method, and the anterograde dissociation of the vasal vessels on the distal testicular side was adopted as a supplement to dissociate the vasal vessels to be preserved. This improvement ensures the blood supply to the vas deferens that will be used for anastomosis and also provides longer vasal vessels, which reduces the tension of anastomosis. 2) By fixing the vas deferens to be anastomosed and the broken end of the vas deferens, the free vasal vessels get fixed, which resolves the problem of transmission of vas tension to the vasal vessels and reduces the risk of vasal vessel hemorrhage. 3) Dissociation of the vas deferens after opening the tunica vaginalis increases the mobilization of the vas deferens, which also makes the new procedure easier to complete. The evaluation of the outcomes of this new procedure showed that no significant postoperative complications occurred in the patients, and the patency rate was no different from that of the conventional procedure. Therefore, this new, improved procedure can be considered safe, with satisfactory postoperative results.

Here, we present a protocol to preserve the vasal vessels in microsurgical vasoepididymostomy. The surgical security is enhanced by preserving the vasal vessels using a retrograde-anterograde dissociation and fixing the vasal vessels.

Microsurgical vasoepididymostomy (MVE) is the main surgical treatment for epididymal obstruction. The vasal vessels are ligated during MVE. However, ...