This research was supported by the Youth Science and Technology Project of the Department of Health of Hebei Province. (No.20201046).

The protocol follows the guidelines of the Ethics Committee of the Third Hospital of Hebei Medical University. Informed consent was obtained from the patients for including them and the data generated as a part of this study. Patients enrolled in this study were between the ages of 18-60. A total of eight patients were included in the study, five females and three males.
1. Preoperative preparation
<ol>
	<li>Use the following inclusion and exclusion criteria for enrolling patients in this study.
	<ol>
		<li>Use these inclusion criteria: Patients with a clear diagnosis of posterior cruciate ligament cyst by MRI of the knee; patients with significant knee pain, hyperextension pain, and other symptoms that may be caused by posterior cruciate ligament cyst or patients with combined meniscal injuries that require arthroscopic treatment; patients who have an interest in surgery because of the impact on their quality of life.</li>
		<li>Use these exclusion criteria: Patients with other serious medical conditions who cannot tolerate surgery; patients who refuse surgical treatment; patients with posterior cruciate ligament cyst diagnosed by MRI but without symptoms; patients with combined anterior cruciate ligament rupture or posterior cruciate ligament rupture.</li>
	</ol>
	</li>
	<li>Use general anesthesia or neuraxial anesthesia for all patients. Place the patient in the supine position on the surgical bed. Apply a tourniquet to the affected limb in the middle and upper part of the thigh for no more than 1 h. Disinfect the affected limb 2x with iodophor and lay the surgical sheet.</li>
</ol>
2. Establishment of arthroscopic approaches
<ol>
	<li>Use a blood-repellent belt to expel blood from the affected limb. Tighten the blood-repellent belt from the end of the limb to the proximal end. Make each lap overlap by 1/3. Do not insert soft tissue between each turn. Drain blood from the soft tissues of the operated limb. Inflate the tourniquet by applying 50 kPa pressure/force.</li>
	<li>Establish an anterolateral approach, 1 cm above the lateral knee line and 1 cm lateral to the patellar tendon margin. Make an incision of about 0.5 cm in size from the skin to the joint cavity using an 11G sharp blade.</li>
	<li>Establish an anteromedial approach, 1 cm above the medial knee articular line and 1 cm medial to the patellar tendon margin. Make an incision of about 0.5 cm in size from the skin to the joint cavity using an 11G sharp blade.</li>
	<li>Insert the arthroscope parallel to the tibial platform towards the intercondylar fossa in medial and lateral approaches, respectively. Explore the suprapatellar capsule, patellofemoral joint, medial trochanteric clearance, lateral trochanteric sulcus, anterior cruciate ligament, posterior cruciate ligament, medial meniscus, and lateral meniscus.</li>
	<li>Partially remove the injured meniscus or suture the injured meniscus. Remove the joint-free body. Treat all injuries within the joint.</li>
	<li>Establish a normal posteromedial approach as described below.
	<ol>
		<li>Flex the knee at 90&#176;. Insert the arthroscopy in the anteromedial approach to monitor the intercondylar fossa and place the switching rod in the anterolateral approach.</li>
		<li>Insert the exchange rod between the posterior cruciate ligament (PCL) and the medial femoral condyle into the posteromedial joint capsule under arthroscopic surveillance. There is usually a distinct sensation of slipping in and out.</li>
		<li>Rotate the lens to the medial posterior joint capsule. See the triangular area formed by the reverse fold of the joint capsule, the medial femoral condyle, and the medial meniscus.</li>
		<li>Turn off the operating room lights. Observe the translucent area of the posterior medial skin surface of the knee (Figure 2).</li>
		<li>Use a lumbar needle to assist positioning (Figure 3). Eccentric puncture into the joint capsule in the translucent area (usually 0.5-1 cm behind the posterior femoral condyle and proximal to the articular line).</li>
		<li>Make a small incision of about 0.5 cm in the skin using an 11G sharp blade. Insert a straight clamp into the joint capsule under arthroscopic surveillance. Establish a normal posteromedial approach.</li>
	</ol>
	</li>
	<li>Establish a high posteromedial approach as described below.
	<ol>
		<li>Insert the arthroscopy into the posteromedial approach. Insert the lumbar needle in the direction of the joint, 2-3 cm proximal to the posteromedial approach.</li>
		<li>Make the lumbar needle penetrate into the joint capsule in the triangular space of the medial posterior condyle, medial meniscus, and posterior joint capsule.</li>
		<li>Make a small incision in the skin. Insert a straight clamp into the joint capsule under arthroscopic surveillance. Establish a high posteromedial approach.</li>
	</ol>
	</li>
</ol>
3. Exposing and removing posterior cruciate ligament cysts
<ol>
	<li>Insert the arthroscopy in the high posteromedial approach. Insert the shaver in the normal posteromedial approach (Figure 4).</li>
	<li>Remove synovial tissue between the posterior cruciate ligament and the joint capsule using a shaver.</li>
	<li>Find the cyst, which is a translucent, raised synovial membrane around the posterior cruciate ligament (Figure 1C). Remove the cyst wall and see yellow and translucent fluid flowing out of the cyst wall, visualize compartment-like tissue in the cyst.</li>
	<li>Remove the posterior cyst wall completely. Avoid injury to the posterior cruciate ligament and posterior blood vessels and nerves and explore the posterior cruciate ligament without injury.</li>
	<li>Insert the arthroscopy in the anterolateral approach. See a portion of the cyst at the femoral terminus of the posterior cruciate ligament.</li>
	<li>Remove the anterior cyst wall and see yellow and translucent fluid flowing out of the cyst wall. Remove the cyst wall completely.</li>
	<li>Remove the synovial tissue in the V-shaped space between the anterior cruciate ligament and the posterior cruciate ligament. Probe the posterior cruciate ligament and check for damage to the posterior cruciate ligament.</li>
	<li>Insert the arthroscopy in the medial patellar approach. Check the V-shaped space between the anterior cruciate ligament and the posterior cruciate ligament for residual cysts.</li>
	<li>Insert the arthroscopy in the posteromedial approach. Check for residual cysts.</li>
</ol>
4. Closure of the incision
<ol>
	<li>Insert the arthroscopic sheath in the anterolateral approach. Squeeze the suprapatellar capsule and completely drain the intra-articular fluid. Check knee extension and flexion activities from 0&#176; to 120&#176;.</li>
	<li>Suture the incision with silk thread No. 4.</li>
</ol>
5. Postoperative rehabilitation
<ol>
	<li>Quadriceps exercise: Ask the patient to perform this exercise in the supine position. Straighten the affected limb, hook up the toes, slowly lift the leg upward to a height of about 15 cm on the heel, stay for 3 seconds, and then slowly lower it down.</li>
	<li>Joint release training: Ask the patients to perform this as they sit at the bedside and extend and flex the knee joint by themselves.</li>
	<li>Ask the patient to get out of bed on the second day after surgery and move appropriately, and gradually return to normal activities.</li>
	<li>Change the dressing every 3 days after surgery and remove the stitches 14 days after surgery.</li>
	<li>Ask the patient to perform non-confrontational activities such as jogging in the first month after surgery and resume normal activities in the third month after surgery.</li>
</ol>
6. Postoperative care and follow-up
<ol>
	<li>Ask the patient to lie flat without the pillow for 6 hours after surgery. The patient was hospitalized for approximately 3 days.</li>
	<li>At 3 months after surgery, check whether the patient&#39;s range of motion returns to normal and 12 months after surgery, perform an MRI examination of the affected knee combined with arthroscopy to check whether there is discomfort in the affected knee and whether the cyst has recurred.</li>
</ol>

Arthroscopic Double Posteromedial Approach for PCL Cyst Excision

<ol>
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Intraarticular ganglion arising from the posterior cruciate-ligament.</a> Skeletal Radiol. 20 (5), 373-375 (1991).</li><li>Garc&#237;a-Alvarez, F., Garc&#237;a-Pequerul, J. M., Avila, J. L., Sainz, J. M., Castiella, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ganglion+cysts+associated+with+cruciate+ligaments+of+the+knee:+A+possible+cause+of+recurrent+knee+pain.">Ganglion cysts associated with cruciate ligaments of the knee: A possible cause of recurrent knee pain.</a> Acta Orthop Belg. 66 (5), 490-494 (2000).</li><li>Brown, M. F., Dandy, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intra-articular+ganglia+in+the+knee.">Intra-articular ganglia in the knee.</a> Arthroscopy. 6 (4), 322-323 (1990).</li><li>Kim, M. 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=Intra-articular+ganglion+cysts+of+the+knee:+Clinical+and+MR+imaging+features.">Intra-articular ganglion cysts of the knee: Clinical and MR imaging features.</a> Eur Radiol. 11 (5), 834-840 (2001).</li><li>Kim, R. S., Kim, K. T., Lee, J. Y., Lee, K. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ganglion+cysts+of+the+posterior+cruciate+ligament.">Ganglion cysts of the posterior cruciate ligament.</a> Arthroscopy. 19 (6), e36-e40 (2003).</li><li>Shetty, G. 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K., Abed Ali, A., Alayane, A., Bayoud, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+uncommon+finding+of+posterior+cruciate+ligament+intrasubstance+cyst:+A+case+report+and+review+of+literature.">An uncommon finding of posterior cruciate ligament intrasubstance cyst: A case report and review of literature.</a> J Orthop Case Rep. 12 (3), 61-63 (2022).</li><li>Jawish, R., Nemer, C., Assoum, H., Haddad, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ganglion+cyst+of+the+anterior+cruciate+ligament+in+children.">Ganglion cyst of the anterior cruciate ligament in children.</a> J Pediatr Orthop B. 18 (5), 234-237 (2009).</li><li>Bui-Mansfield, L. T., Youngberg, R. 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The authors declare that there are no conflicts of interest in this study.

Posterior cruciate ligament cyst is a rare disease. Knee ligament cysts are usually discovered during MRI or knee arthroscopy exams. The causes of knee ligament cyst formation are varied, including post-traumatic formation, synovial tissue hernia formation during embryogenesis, and mesenchymal stem cell proliferation and formation. Recently, trauma and tissue stimulation have been recognized by most experts2,7,14.
<p class="...

Joint cysts are cystic lesions, and the cyst fluid is a transparent jelly-like fluid that can be found in the ligament, meniscus, synovial membrane, and other parts of the knee joint1,2. High mechanical stress can easily lead to cyst formation, which is why cysts are most common in the knee joint3,4, and Baker&#39;s cysts are the most common type of cysts5. Cruciate ligament cysts of the knee are rare, occurring incidentally in 0.2% to 1.3% of cases scanned using knee magnetic resonance imaging (MRI) and in 0.6% of patients tested using knee arthroscopy6,7. Posterior cruciate ligament cysts are rarer, with Brown and Dandy reporting that after performing knee arthroscopy on 6,500 patients, they found only 35 ligament cysts and only 6 from the posterior cruciate ligament5. Knee ligament cysts can occur regardless of sex or age but are more common in men aged 20 years to 40 years4,8.
The cause of cruciate ligament cysts is unknown. For the non-invasive diagnosis of knee ligament cysts, MRI can clearly show the relationship between the size and position of the cyst and is the most accurate diagnostic method4,6,9,10. Arthroscopic removal of cysts is the most effective and recommended treatment method4,6,9,10. Arthroscopy can see the cyst site directly and completely remove the cyst wall, the recurrence rate is extremely low, and the patient recovers quickly after surgery7,9,10. Posterior cruciate ligament cysts are mostly lobulated or multiloculated, most of which are located mainly behind the posterior cruciate ligament, and in 12.5% of patients, the cyst is mainly located anterior to the posterior cruciate ligament11 (Figure 1A,B).
Many treatments can be used to treat posterior cruciate ligament cysts, such as ultrasound and computed tomography-guided joint paracentesis. However, several studies have shown that there is a potentially higher risk of recurrence because of which these procedures do not remove the cyst walls12. Arthroscopic removal of cysts is the gold standard for the treatment of posterior cruciate ligament cysts. Arthroscopic surgery can completely remove the cyst wall, but it&#39;s hard to remove dorsal cruciate ligament cysts by the anterior approach alone. Abreu et al.12 introduced an approach to the arthroscopic excision of PCL cysts using a trans-septal portal, and it&#39;s safe and effective. Tsai et al.13 reported that the trans-septal approach to the resection of posterior cruciate ligament cysts was successful in 15 patients, and there was no recurrence. The trans-septal approach requires the addition of a posterolateral approach, so it increases the risk of damaging the common peroneal nerve and popliteal neurovascular bundle. To avoid these risks, we present a surgical approach to treat posterior cruciate ligament cysts by an arthroscopic double posteromedial approach. Our approach does not require an additional posterolateral approach; there is no risk of injuring the common peroneal nerve. We use the double posteromedial approach, which keeps the entire surgical process on the medial side of the posterior septal, thus reducing the possibility of damaging the popliteal neurovascular bundle. The technique produces the same results while being safer than the trans-septal approach. This surgical approach is particularly suitable for the removal of cysts located on the dorsal side of the posterior cruciate ligament. The surgical approach is more advantageous if the cyst is compartmentalized or close to the tibial end.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Arthroscopic sheath&#160;</td>
			<td>smith&#38;nephew</td>
			<td>72200829</td>
			<td>6mm</td>
		</tr>
		<tr>
			<td>Arthroscopy</td>
			<td>smith&#38;nephew</td>
			<td>72202087</td>
			<td>30 mm x 4 mm</td>
		</tr>
		<tr>
			<td>Beam guide&#160;&#160;&#160;&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>72204925</td>
			<td>5 mm x 3.6 m</td>
		</tr>
		<tr>
			<td>Beam guide-arthroscopy end connector&#160;</td>
			<td>smith&#38;nephew</td>
			<td>2143</td>
			<td></td>
		</tr>
		<tr>
			<td>Beam guide-panel connector&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>2147</td>
			<td></td>
		</tr>
		<tr>
			<td>Blood-repellent belt</td>
			<td>selani</td>
			<td>tpe15100</td>
			<td>15 cm x 1 m</td>
		</tr>
		<tr>
			<td>Blunt puncture cone&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>4356</td>
			<td>4 mm</td>
		</tr>
		<tr>
			<td>Camera&#160;&#160;&#160;&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>72200561</td>
			<td>NTSC/PAL</td>
		</tr>
		<tr>
			<td>Coupler&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>72200315</td>
			<td></td>
		</tr>
		<tr>
			<td>DYONICS POWER II</td>
			<td>smith&#38;nephew</td>
			<td>72200873</td>
			<td>100-24VAC, 50/60Hz</td>
		</tr>
		<tr>
			<td>DYONICS POWERMAX ELITE</td>
			<td>smith&#38;nephew</td>
			<td>72200616</td>
			<td></td>
		</tr>
		<tr>
			<td>Endoscopic camera system</td>
			<td>smith&#38;nephew</td>
			<td>72201919</td>
			<td>560P NTSC/PAL</td>
		</tr>
		<tr>
			<td>HD monitor&#160;</td>
			<td>smith&#38;nephew</td>
			<td>&#160;LB500031</td>
			<td>27 inch&#160;</td>
		</tr>
		<tr>
			<td>Hook probe&#160;</td>
			<td>smith&#38;nephew</td>
			<td>3312</td>
			<td></td>
		</tr>
		<tr>
			<td>Incisor plus platinum shaver&#160;&#160;&#160;&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>72202531</td>
			<td>&#160;4.5 mm</td>
		</tr>
		<tr>
			<td>Lumbar needle&#160; AN-E/S&#160;<img alt="Equation 1" src="/files/ftp_upload/65620/65620eq01.jpg" style="margin: auto;" /></td>
			<td>tuoren</td>
			<td>AN-E/S&#160;<img alt="Equation 1" src="/files/ftp_upload/65620/65620eq01.jpg" style="margin: auto;" /></td>
			<td>1.6 mm x 80 mm</td>
		</tr>
		<tr>
			<td>Micropunch,teardrop,left&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>7207602</td>
			<td></td>
		</tr>
		<tr>
			<td>Micropunch,teardrop,right&#160;</td>
			<td>smith&#38;nephew</td>
			<td>7207601</td>
			<td></td>
		</tr>
		<tr>
			<td>Micropunch,teardrop,straight&#160;</td>
			<td>smith&#38;nephew</td>
			<td>7207600</td>
			<td></td>
		</tr>
		<tr>
			<td>Pitbull Jr. Grasper&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>14845</td>
			<td></td>
		</tr>
	</tbody>
</table>

arthroscopic excision of posterior cruciate ligament cysts using a double posteromedial approach

Cruciate ligament cysts of the knee are a rare condition. Posterior cruciate ligament cysts of the knee are less common than anterior cruciate ligament cysts. In patients with asymptomatic isolated cruciate ligament cysts of the knee, conservative treatment is recommended. Symptomatic cruciate ligament cysts of the knee are mostly manifested as knee hyperflexion pain, straightening pain, knee discomfort after standing for a long time or walking for a long time, etc., which seriously affects the quality of life, surgical treatment can be performed. The surgical treatments can be divided into ultrasound-guided cyst puncture and fluid extraction procedure and arthroscopic cystectomy. Cysts are mostly lobulated with a multi-layer cyst wall, cyst fluid extraction does not remove the cyst wall completely but simply extracts cyst fluid, leading to a high recurrence rate. Arthroscopic surgery can completely remove the cyst wall with little trauma, a low recurrence rate, and fast postoperative recovery, so arthroscopic resection is the most common and preferred method of treatment. Since posterior cruciate ligament cysts mostly occur posterior to the ligament, we remove the cyst wall by adding a double posteromedial approach to the knee joint, and the cyst wall is removed under direct vision, which is simple to operate, the cyst wall is completely cleared, the trauma is small, the postoperative recovery is fast, and there is no recurrence. Here, 8 posterior cruciate ligament cysts were removed with complete postoperative symptom relief, no surgical complications, and no recurrence at 1-year follow-up.

All eight patients were successfully operated on without any complications. Seven of the 8 patients had isolated posterior cruciate ligament cysts, and 1 patient had medial meniscal injury. The main symptoms of all patients before surgery are knee hyperflexion pain, inability to squat freely, pain, and discomfort in the back of the knee after standing for a long time or walking for a long time. After surgery, all symptoms were relieved and disappeared (Table 1).
Of the 7 patie...

Read this Scientific Article Protocol about Author Spotlight: Double Posteromedial Approach for Treating Posterior Cruciate Ligament Cysts at JoVE.com

Author Spotlight: Double Posteromedial Approach for Treating Posterior Cruciate Ligament Cysts

We present a surgical approach to treat posterior cruciate ligament cysts by an arthroscopic double posteromedial approach.

Arthroscopic Excision of Posterior Cruciate Ligament Cysts Using a Double Posteromedial Approach

Cruciate ligament cysts of the knee are a rare condition. Posterior cruciate ligament cysts of the knee are less common than anterior cruciate ligament ...

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445 Views.  The Third Hospital of Hebei Medical University. We present a surgical approach to treat posterior cruciate ligament cysts by an arthroscopic double posteromedial approach.

Video: Author Spotlight: Double Posteromedial Approach for Treating Posterior Cruciate Ligament Cysts

Preparation and Pathogen Inactivation of Double Dose Buffy Coat Platelet Products using the INTERCEPT Blood System

Blood centers are faced with many challenges including maximizing production yield from the blood product donations they receive as well as ensuring the highest possible level of safety for transfusion patients, including protection from transfusion transmitted diseases. This must be accomplished in a fiscally responsible manner which minimizes operating expenses including consumables, equipment, waste, and personnel costs, among others.
Several methods are available to produce platelet concentrates for transfusion. One of the most common is the buffy coat method in which a single therapeutic platelet unit (&ge; 2.0 x1011 platelets per unit or per local regulations) is prepared by pooling the buffy coat layer from up to six whole blood donations. A procedure for producing "double dose" whole blood derived platelets has only recently been developed.
Presented here is a novel method for preparing double dose whole blood derived platelet concentrates from pools of 7 buffy coats and subsequently treating the double dose units with the INTERCEPT Blood System for pathogen inactivation. INTERCEPT was developed to inactivate viruses, bacteria, parasites, and contaminating donor white cells which may be present in donated blood. Pairing INTERCEPT with the double dose buffy coat method by utilizing the INTERCEPT Processing Set with Dual Storage Containers (the "DS set"), allows blood centers to treat each of their double dose units in a single pathogen inactivation processing set, thereby maximizing patient safety while minimizing costs. The double dose buffy coat method requires fewer buffy coats and reduces the use of consumables by up to 50% (e.g. pooling sets, filter sets, platelet additive solution, and sterile connection wafers) compared to preparation and treatment of single dose buffy coat platelet units. Other cost savings include less waste, less equipment maintenance, lower power requirements, reduced personnel time, and lower collection cost compared to the apheresis technique.

This article describes the process used by &#214;rebro University Hospital to produce double dose buffy coat platelet concentrates prepared from whole blood donations and treated with the INTERCEPT Blood System for pathogen inactivation. The in vitro quality of the final platelet units are evaluated over 7 days of storage.

Blood centers are faced with many challenges including maximizing production yield from the blood product donations they receive as well as ensuring the ...

A Possible Zebrafish Model of Polycystic Kidney Disease: Knockdown of wnt5a Causes Cysts in Zebrafish Kidneys

Polycystic kidney disease (PKD) is one of the most common causes of end-stage kidney disease, a devastating disease for which there is no cure. The molecular mechanisms leading to cyst formation in PKD remain somewhat unclear, but many genes are thought to be involved. Wnt5a is a non-canonical glycoprotein that regulates a wide range of developmental processes. Wnt5a works through the planar cell polarity (PCP) pathway that regulates oriented cell division during renal tubular cell elongation. Defects of the PCP pathway have been found to cause kidney cyst formation. Our paper describes a method for developing a zebrafish cystic kidney disease model by knockdown of the wnt5a gene with wnt5a antisense morpholino (MO) oligonucleotides. Tg(wt1b:GFP) transgenic zebrafish were used to visualize kidney structure and kidney cysts following wnt5a knockdown. Two distinct antisense MOs (AUG - and splice-site) were used and both resulted in curly tail down phenotype and cyst formation after wnt5a knockdown. Injection of mouse Wnt5a mRNA, resistant to the MOs due to a difference in primary base pair structure, rescued the abnormal phenotype, demonstrating that the phenotype was not due to &#8220;off-target&#8221; effects of the morpholino. This work supports the validity of using a zebrafish model to study wnt5a function in the kidney.

A Possible Zebrafish Model of Polycystic Kidney Disease: Knockdown of wnt5a Causes Cysts in Zebrafish Kidneys

We describe a method of generating a possible zebrafish model of polycystic kidney disease. We used Tg(wt1b:GFP) fish to visualize kidney structure. Knockdown of wnt5a was by morpholino injection. Pronephric cyst formation after wnt5a knockdown was observed in this GFP transgenic zebrafish.

Polycystic kidney disease (PKD) is one of the most common causes of end-stage kidney disease, a devastating disease for which there is no cure. The ...

Isolation and Excision of Murine Aorta; A Versatile Technique in the Study of Cardiovascular Disease

Cardiovascular disease is a broad term describing disease of the heart and/or blood vessels. The main blood vessel supplying the body with oxygenated blood is the aorta. The aorta may become affected in diseases such as atherosclerosis and aneurysm. Researchers investigating these diseases would benefit from direct observation of the aorta to characterize disease progression as well as to evaluate efficacy of potential therapeutics. The goal of this protocol is to describe proper isolation and excision of the aorta to aid investigators researching cardiovascular disease. Isolation and excision of the aorta allows investigators to look at gross morphometric changes as wells as allowing them to preserve and stain the tissue to look at histologic changes if desired. The aorta may be used for molecular studies to evaluate protein and gene expression to discover targets of interest and mechanisms of action. This technique is superior to imaging modalities as they have inherent limitations in technology and cost. Additionally, primary isolated cells from a freshly isolated and excised aorta can allowing researchers to perform further in situ and in vitro assays. The isolation and excision of the aorta has the limitation of having to sacrifice the animal however, in this case the benefits outweigh the harm as it is the most versatile technique in the study of aortic disease.

Pathology of the aorta can lead to severe morbidity and mortality, therefore research of disease progression and potential therapies is warranted. Here, we present a protocol to isolate and excise the murine aorta to aid researchers in their investigation of cardiovascular disease.

Cardiovascular disease is a broad term describing disease of the heart and/or blood vessels. The main blood vessel supplying the body with oxygenated ...

Localization, Identification, and Excision of Murine Adipose Depots

Obesity has increased dramatically in the last few decades and affects over one third of the adult US population. The economic effect of obesity in 2005 reached a staggering sum of $190.2 billion in direct medical costs alone. Obesity is a major risk factor for a wide host of diseases. Historically, little was known regarding adipose and its major and essential functions in the body. Brown and white adipose are the two main types of adipose but current literature has identified a new type of fat called brite or beige adipose. Research has shown that adipose depots have specific metabolic profiles and certain depots allow for a propensity for obesity and other related disorders. The goal of this protocol is to provide researchers the capacity to identify and excise adipose depots that will allow for the analysis of different factorial effects on adipose; as well as the beneficial or detrimental role adipose plays in disease and overall health. Isolation and excision of adipose depots allows investigators to look at gross morphological changes as well as histological changes. The adipose isolated can also be used for molecular studies to evaluate transcriptional and translational change or for in vitro experimentation to discover targets of interest and mechanisms of action. This technique is superior to other published techniques due to the design allowing for isolation of multiple depots with simplicity and minimal contamination.

Due to the drastic and negative connection between obesity and other comorbidities, research on the role adipose plays in disease and overall health is warranted. We present a protocol for the isolation and excision of adipose depots allowing for the study of adipose using in situ and in vitro methods.

Obesity has increased dramatically in the last few decades and affects over one third of the adult US population. The economic effect of obesity in 2005 ...

Rat Model of Photochemically-Induced Posterior Ischemic Optic Neuropathy

Posterior Ischemic optic neuropathy (PION) is a sight-devastating disease in clinical practice. However, its pathogenesis and natural history have&#160;remained poorly understood. Recently, we developed a reliable, reproducible animal model of PION and tested the treatment effect of some neurotrophic factors in this model1. The purpose of this video is to demonstrate our photochemically induced model of posterior ischemic optic neuropathy, and to evaluate its effects with retrograde labeling of retinal ganglion cells. Following surgical exposure of the posterior optic nerve, a photosensitizing dye, erythrosin B, is intravenously injected and a laser beam is focused onto the optic nerve surface. Photochemical interaction of erythrosin B and the laser during irradiation damages the vascular endothelium, prompting microvascular occlusion mediated by platelet thrombosis and edematous compression. The resulting ischemic injury yields a gradual but pronounced retinal ganglion cell dieback, owing to a loss of axonal input - a remote, injury-induced and clinically relevant outcome. Thus, this model provides a novel platform to study the pathophysiologic course of PION,&#160;and can be further optimized for testing therapeutic approaches for optic neuropathies as well as other CNS ischemic diseases.

The goal of this protocol is to photochemically induce ischemic injury to the posterior optic nerve in rat. This model is critical to studies of the pathophysiology of posterior ischemic optic neuropathy, and therapeutic approaches for this and other optic neuropathies, as well as of other CNS ischemic diseases.

Posterior Ischemic optic neuropathy (PION) is a sight-devastating disease in clinical practice. However, its pathogenesis and natural history ...

Autologous Microfractured and Purified Adipose Tissue for Arthroscopic Management of Osteochondral Lesions of the Talus

In recent years, regenerative techniques have been increasingly studied and used to treat osteochondral lesions of the talus. In particular, several studies have focused their attention on mesenchymal stem cells derived from adipose tissue. Adipose-derived stem cells (ADSCs) exhibit morphological characteristics and properties similar to other mesenchymal cells, and are able to differentiate into several cellular lines. Moreover, these cells are also widely available in the subcutaneous tissue, representing 10 - 30% of the normal body weight, with a concentration of 5,000 cells per gram of tissue.
In the presented technique, the first step involves harvesting ADSCs from the abdomen and a process of microfracture and purification; next, the surgical procedure is performed entirely arthroscopically, with less soft tissue dissection, better joint visualization, and a faster recovery compared with standard open procedures. Arthroscopy is characterized by a first phase in which the lesion is identified, isolated, and prepared with microperforations; the second step, performed dry, involves injection of adipose tissue at the level of the lesion.
Between January 2016 and September 2016, four patients underwent arthroscopic treatment of osteochondral lesion of the talus with microfractured and purified adipose tissue. All patients reported clinical improvement six months after surgery with no reported complications. Functional scores at the latest follow-up are encouraging and confirm that the technique provides reliable pain relief and improvements in patients with osteochondral lesion of the talus.

The aim of this study is to report a protocol for the arthroscopic treatment of osteochondral lesions of the talus using microfractured and purified adipose-derived stem cells.

In recent years, regenerative techniques have been increasingly studied and used to treat osteochondral lesions of the talus. In particular, several ...

Posterior Semicircular Canal Approach for Inner Ear Gene Delivery in Neonatal Mouse

Inner ear gene therapy offers great promise as a potential treatment for hearing loss and dizziness. One of the critical determinants of the success of inner ear gene therapy is to find a delivery method which results in consistent transduction efficiency of targeted cell types while minimizing hearing loss. In this study, we describe the posterior semicircular canal approach as a viable method for inner ear gene delivery in neonatal mice. We show that gene delivery through the posterior semicircular canal is able to perfuse the entire inner ear. The easy anatomic identification of the posterior semicircular canal, as well as minimal manipulation of the temporal bone required, make this surgical approach an attractive option for inner ear gene delivery.

In this study, we describe the posterior semicircular canal approach as a reliable method for inner ear gene delivery in neonatal mice. We show that gene delivery through the posterior semicircular canal is able to perfuse the entire inner ear.

Inner ear gene therapy offers great promise as a potential treatment for hearing loss and dizziness. One of the critical determinants of the success of ...

Vessel-sparing Excision and Primary Anastomosis

Urethroplasty is considered to be the standard treatment for urethral strictures since it provides excellent long-term success rates. For isolated short bulbar or posterior urethral strictures, urethroplasty by excision and primary anastomosis (EPA) is recommended. As EPA only requires the excision of the narrowed segment and the surrounding spongiofibrosis, a full-thickness transection of the corpus spongiosum, as performed in the traditional transecting EPA (tEPA), is usually unnecessary. Jordan et al. introduced the idea of a vessel-sparing approach in 2007, aiming to reduce surgical trauma, especially to the dual arterial blood supply of the urethra, and, thus, potentially reducing the risk of postoperative erectile dysfunction or glans ischemia. This approach could also be beneficial for subsequent urethral interventions such as redo urethroplasty using a free graft, in which a well-vascularized graft bed is imperative. Nevertheless, these potential benefits are only assumptions as prospective studies comparing the functional outcome of both techniques with validated questionnaires are currently lacking. Moreover, vessel-sparing EPA (vsEPA) should at least be able to provide similar surgical outcomes as tEPA. The aim of this paper is to give an elaborate, step-by-step overview of how to manage patients with isolated short bulbar or posterior urethral strictures with vsEPA. The main objective of this manuscript is to outline the surgical technique and to report the representative surgical outcome. A total of 117 patients were managed according to the described protocol. The analysis was performed on the entire patient cohort and on the bulbar (n = 91) and posterior (n = 26) vsEPA group separately. Success rates were 93.4% and 88.5% for the bulbar and posterior vsEPA, respectively. To conclude, vsEPA, as outlined in the protocol, provides excellent success rates with low complication rates for isolated short bulbar and posterior urethral strictures.

Here, we present an elaborate and efficient protocol to treat isolated short bulbar or posterior urethral strictures with vessel-sparing excision and primary anastomosis.

Urethroplasty is considered to be the standard treatment for urethral strictures since it provides excellent long-term success rates. For isolated short ...

Posterior Approach for Debridement of the Psoas Abscess

This method focuses on outlining a safe zone for irrigation and debridement of a psoas abscess through a posterior approach. Initially, an anterior approach to the spine was performed to ensure that the anterior longitudinal ligament and the psoas muscle could be visualized. All the abdominal organs were removed. Subsequently, a posterior approach was performed to remove the paraspinal muscles from L1&#8211;L5. The transverse processes, pars interarticularis and lamina of L1&#8211;L5 were identified. The exiting nerve root was identified between the transverse processes and followed into the substance of the psoas muscle. Using the anterior and posterior approach, the lumbar plexus was isolated from the substance of the psoas muscle. Before and after various steps of dissection, digital photographs were obtained. These images were uploaded into ImageJ and multiple measurements, including the distance between the lateral superior and inferior tip of each TP to the most lateral region of the plexus, the distance between the lateral superior and inferior tip of the TP to the lateral edge of the psoas, and the width of the lumbar plexus were recorded. The safe zone for entering the substance of the psoas muscle was defined between the lateral edge of the psoas muscle and the lateral edge of the lumbar plexus. The relationship of this interval to the tip of the transverse process at each level was measured and reported.

This is a cadaveric study investigating the landmarks for the posterior approach for irrigation and debridement of the psoas abscess. The interval between the transverse processes (TP) was used to access the substance of the psoas muscle.

This method focuses on outlining a safe zone for irrigation and debridement of a psoas abscess through a posterior approach. Initially, an anterior ...

Endoscopy Guided Photoablation of Endometrial Cysts using a 980 nm Laser with a Contact Fiber in Mares

In mares, endometrial cysts are associated with endometriosis and can cause maternal recognition failure or compromise and delay pregnancy diagnoses. Historical treatments were invasive and had adverse effects on the endometrium. Hysteroscopically guided laser therapy is easy and effective for endometrial cysts resection, with no deleterious effects for the endometrium.
A 110 cm long and 1.0 cm wide endoscope is sterilely introduced in the uterus through the open cervix of an estrous mare after vulvar cleaning. The uterus is slowly infused with less than 1 L of physiologic solution and the laser fiber is inserted in the biopsy canal of the endoscope. Cysts are then cauterized with the 980 nm diode laser with a contact fiber set at 20&#8210;2 5W in continuous mode. Each cyst is punctured&#160;until complete voiding of the cyst and shrinking of the cyst wall around the fiber. Uterine lavages with sterile saline solution are performed directly after the surgery and for one or two days as non-inflammatory fluid can be observed.
This procedure is easy and quickly performed, with no obvious deleterious effects. Cysts resection makes ultrasound pregnancy diagnosis easier and, in some cases, could restore proper embryo migration in the uterine horns between day 6.5 and 17. However, this treatment does not improve the underlying histological lesions related to endometriosis. These considerations should be clearly expressed to the breeder before this procedure.

The aim of this report is to describe the photoablation of endometrial cysts in the mare using an endoscopic laser device, and to discuss the interest and limitations of this new approach to deal with low fertility issues.

In mares, endometrial cysts are associated with endometriosis and can cause maternal recognition failure or compromise and delay pregnancy diagnoses. ...