Editing Inguinal Node Dissection (section)

=== Standard radical inguinal lymphadenectomy ===
*'''In the standard radical inguinal lymphadenectomy, both the superficial and deep inguinal lymph nodes are removed'''
*'''<span style="color:#ff0000">Indications[https://pubmed.ncbi.nlm.nih.gov/27717432/]</span>'''
**'''<span style="color:#ff0000">Clinically node-positive disease (palpable on physical exam)</span>'''

==== Boundaries of Dissection[https://pubmed.ncbi.nlm.nih.gov/16643509/ §] ====
* '''<span style="color:#ff0000">Superficial: Camper's fascia[https://www.youtube.com/watch?v=5HdhCDdDnP0]</span>'''
* '''<span style="color:#ff0000">Superior: inguinal ligament/superior boundary of the external oblique aponeurosis and the spermatic cord</span>'''
**'''<span style="color:#ff0000">Inguinal ligament is the portion of the external oblique aponeurosis which extends between the anterior superior iliac spine and the pubic tubercle as a thick band, folded inward[https://en.wikipedia.org/wiki/Aponeurosis_of_the_abdominal_external_oblique_muscle]</span>'''
* '''<span style="color:#ff0000">Medial: anterolateral border of adductor longus muscle</span>'''
* '''<span style="color:#ff0000">Lateral: sartorious muscle</span> (saphenous vein and femoral vein in modified template)[https://pubmed.ncbi.nlm.nih.gov/16643509/]'''
* '''<span style="color:#ff0000">Inferior: apex of the femoral triangle/fossa ovalis (where the saphenous penetrates the fascia lata)</span>'''
*'''<span style="color:#ff0000">Floor: pectineus muscle for deep dissection (fascia lata for superficial)</span>'''
**Note that adductor longus and sartorious are posterior to fascia lata and are therefore not the relevant medial and lateral boundaries for superficial dissection.
==== Step by step ====
* See [https://pubmed.ncbi.nlm.nih.gov/16643509/ BJUI Surgical atlas. Surgical management of penile carcinoma: the inguinal nodes]
*'''General anesthesia and insertion of lines.''' No need for naso/orograstric tube for gastric decompression during case.
* '''Patient positioning, antiseptic preparation, draping.'''
** After induction of general anesthesia...
** Trim hair overlying operative site, if needed
** Insert 16-Fr Foley catheter
** Externally rotate the hip and flex the knee. Place cushioned support under the flexed knees.
** Prepare area with chlorhexidine–alcohol scrub
***Preoperative skin preparation with a chlorhexidine–alcohol scrub provided a significantly lower surgical site infection rate at 30 days when compared to a skin prep with a povidone–iodine solution
**Drape with exposure of the umbilicus, pubic tubercle, anterior superior iliac spine, and anterior thigh
*'''Use marking pen to denote landmarks and incision.'''
** Landmarks
*** Anterior superior iliac spine
*** Pubic tubercle
****If middle finger is on pubic symphysis, index finger is on pubic tubercle
*** Inguinal ligament (line from anterior superior iliac spine to pubic tubercle)
***Femoral artery (if palpable, usually located approximately at the midpoint of the inguinal ligament)
***Fossa ovalis/saphenous opening (3–4 cm inferior and lateral to the pubic tubercle)
****See [https://radiologykey.com/anatomy-of-the-lower-limb/ Figure 31.2]
*'''Make skin incision[https://pubmed.ncbi.nlm.nih.gov/30730389/]'''
**Lateral end of incision is to a line drawn from the anterior superior iliac spine extending inferiorly and the medial end of the incision is to a line drawn from the pubic tubercle extending inferiorly
***The boundaries of dissection in a radical inguinal lymphadenectomy are defined by the superior margin of the external ring to the anterior superior iliac spine, laterally from the anterior superior iliac spine extending 20 cm inferiorly and medially to a line drawn from the pubic tubercle 15 cm downward[https://pubmed.ncbi.nlm.nih.gov/21481617/]
*'''Develop and raise superior and inferior skin flaps'''
**'''Use left hand to retract and Metzenbaum scissors/cautery to develop and raise superior and inferior skin flaps below Camper's fascia down to the level of the external oblique aponeurosis to expose the inferior border of the inguinal ligament and spermatic cord.'''
*** '''Important to leave a 6—8 mm thickness of subcutaneous tissue in contact with the skin to avoid necrosis[https://www.sciencedirect.com/science/article/pii/S1878788623000292]'''
****Care should be taken to preserve the superficial blood supply to the flaps, thus minimizing the risk of postoperative skin necrosis, infection, and wound breakdown
****Camper’s fascia can be preserved and left attached to the overlying skin when the superior and inferior skin flaps are fashioned.
*****Lymphatic drainage of the penis to the groin runs beneath the Camper fascia
*****Camper's fascia may appear as glistening layer
***Superior skin and subcutaneous tissue flap is developed ≈8 cm superiorly'''[https://pubmed.ncbi.nlm.nih.gov/21481617/]''' towards the inguinal ligament
****Spermatic cord if reflected medially[https://www.youtube.com/watch?v=5HdhCDdDnP0]
***Inferior skin and subcutaneous tissue flap is developed ≈6 cm inferiorly'''[https://pubmed.ncbi.nlm.nih.gov/21481617/]'''
***Develop flap medially to adductor longus aponeurosis
***Develop flap laterally to sartorious
**'''Handle the skin flap edges gently[https://pubmed.ncbi.nlm.nih.gov/27717432/]'''
***'''Assistant uses hooks initially and army navy retractors later to lift up on skin edge'''
***Avoid grasping of the flap edges with forceps because this could potentially crush and devascularize the tissue.
***Consider covering skin flap edges with saline-moistened sponges
**'''Reflect the spermatic cord medially'''
*'''Lymph node dissection'''
**'''Use titanium surgical clips, absorbable suture, or LigaSure for meticulous control of lymphatic channels to avoid a lymphatic leak.<span style="color:#ff0000">[https://link.springer.com/content/pdf/10.1007/978-1-62703-367-1.pdf]</span>'''
**'''The first landmark in the inguinal node dissection is the saphenous vein[https://pubmed.ncbi.nlm.nih.gov/16643509/]'''
**'''Superficial lymph node dissection'''
***'''Remove lymphatic tissue above the fascia lata[https://pubmed.ncbi.nlm.nih.gov/27717432/]'''
****Fascia lata is continuous with Scarpa fascia superiorly, transitions at inguinal ligament
***'''Majority of the lymph nodes will be found in the central and medial zones[https://pubmed.ncbi.nlm.nih.gov/30730389/]'''
****Anatomic lymph groups (5) by location:
****#'''Central nodes around the saphenofemoral junction'''
****#'''Superomedial nodes''' around the superficial external pudendal and superficial epigastric veins
****##'''Drain the prepuce of the penis and the scrotum'''
****#'''Inferomedial nodes around the greater saphenous vein'''
****#Superolateral nodes around the superficial circumflex vein
****#Inferolateral nodes around the lateral femoral cutaneous and superficial circumflex veins
****In obese patients, it may be easy to overlook the superior medial zone nodal tissue if a prominent suprapubic fat pad is present.
***'''Identify and ligate veins in this area''', which can include (see [https://radiologykey.com/wp-content/uploads/2017/12/978-1-62623-013-2_c001_f006a.tif_epub1.jpg Figure])
****Superficial epigastric vein (drains into the greater saphenous vein proximally) at the superior boundary of dissection
****Superficial circumflex iliac vein (drains into the greater saphenous vein laterally) at the superior boundary of dissection
****External pudendal vein (drains into the greater saphenous vein medially)
****Anterior/lateral accessory saphenous vein (drains into the greater saphenous vein laterally)
***Superior boundary: dissect the fat and areolar tissues to the level of the external oblique fascia, the external inguinal ring, and the exposure of the spermatic cord
****Ligate and divide the first lymphatic packet: a funiculus of lymphofatty tissue, extending from the base of the penis to the superomedial portion of this lymph node packet[https://link.springer.com/content/pdf/10.1007/978-1-62703-367-1.pdf][https://pubmed.ncbi.nlm.nih.gov/21481617/]
****Then from the iliac bone, then from the inguinal ligament (this should expose the femoral vessels)[https://www.youtube.com/watch?v=5HdhCDdDnP0]
*** Inferior boundary: inferior angle of the inguinofemoral exposure at the apex of the femoral triangle
*** Lateral boundary: anterior superior iliac spine (circumflex iliac vessels that can be ligated)[https://www.youtube.com/watch?v=5HdhCDdDnP0]
**'''Identify the Great saphenous vein at the inferior boundary of the femoral triangle'''
***'''Great saphenous vein approaches common femoral vein medially'''
***In standard radical inguinal lymphadenectomy, the great saphenous vein and the lateral saphenous vein are divided at the saphenofemoral junction. However, this increases the risk of lower-extremity complications
***In modified inguinal lymphadenectomy (see below), the Great saphenous vein is spared.
****In patients with minimal metastatic disease, it may be feasible and beneficial to spare the saphenous vein.
***Medial boundary: Dissect medially to identify the aponeurosis of the adductor longus muscle of the thigh
***Lateral boundary: Dissect laterally to identify the aponeurosis of the sartorius muscle [or up to the circumflex iliac vessels
** '''Deep lymph node dissection'''
***'''Enter the fascia lata'''
****'''Overlying the sartorius muscle laterally and medially through the thinner fascia of the adductor longus muscle[https://link.springer.com/book/10.1007/978-1-4939-6679-0]'''
****At the level of the saphenous opening[https://pubmed.ncbi.nlm.nih.gov/30730389/] 
*****Lies 3-4cm below and lateral to the pubic tubercle
*****Transmits the great saphenous vein and other smaller vessels including the superficial epigastric artery and superficial external pudendal artery, as well as the femoral branch of the genitofemoral nerve[https://en.wikipedia.org/wiki/Saphenous_opening]
***'''Identify the femoral artery and vein at the apex of the femoral triangle. Use the femoral vessels to guide the dissection along superiorly[https://pubmed.ncbi.nlm.nih.gov/21481617/]'''
****'''The anterior aspects of the femoral vessels are dissected, but the femoral vessels are not skeletonized, and the lateral surface of the femoral artery is not exposed.[https://pubmed.ncbi.nlm.nih.gov/21481617/]'''
***** '''This avoids injury to the femoral nerve and the deep femoral artery'''
****** '''The femoral nerve is usually not visible as it runs beneath the iliacus fascia lateral to the femoral artery.'''
******Branches of the femoral nerve can be on the lateral border of the femoral artery, which must be preserved.
*****'''Be careful when dissecting over the femoral vessels'''
***'''Continue dissection superiorly along the anterior surface of the femoral vein and the femoral artery working medially to laterally over the femoral vein and artery up to the inguinal ligament''' until the femoral canal is reached where continuity to the pelvic dissection is attained to include the deep inguinal nodes.
****The femoral canal is located medial to the femoral vein below the inguinal ligament
****Superficial cutaneous perforating arteries are ligated as they are encountered on the surface of the femoral artery.
***'''Use both blunt and sharp dissection to resect the deep inguinal nodes.'''
****The deep nodes are typically no more than 3–5 lymph nodes contained within the femoral sheath[https://pubmed.ncbi.nlm.nih.gov/30730389/]
*****The node of Cloquet is the most proximal in the femoral canal and considered the margin between the inguinal and pelvic lymph nodes[https://pubmed.ncbi.nlm.nih.gov/30730389/]
******Cloquet’s lymph node is removed.
***'''Clip and transect specimen at the level of the femoral canal'''
**'''Send intraoperative frozen section of lymph node packet'''
***Intraoperative frozen section has been shown to have diagnostic value in determining the need to proceed to a radical dissection[https://pubmed.ncbi.nlm.nih.gov/30730389/]
***It may be time-saving to proceed to the contralateral dissection while awaiting frozen section results.
*'''Apply sartorius flap, if needed, for''' '''coverage over the femoral vessels and nerves'''
**'''If a deep dissection, the sartorius muscle can be transposed or rolled 180 degrees medially by releasing its attachments from the anterior superior iliac spine, providing myocutaneous coverage over the femoral vessels and nerves'''
***The sartorius flap is sutured to the inguinal ligament superiorly with interrupted 2-0 Vicryl sutures, and its margins are sutured to the muscles of the thigh immediately adjacent to the femoral vessels[https://pubmed.ncbi.nlm.nih.gov/21481617/]
*'''Closure'''
** '''Irrigate the wound''' 
*** Irrigate aggressively with water or saline using a bulb syringe to remove small clots and uncover a potential bleeding source.[https://pubmed.ncbi.nlm.nih.gov/18762945/]
** '''Insert multiperforated closed-suction drains (10 or 15 French)''' 
*** Place drains under the subcutaneous tissue in the dissected area along the femoral vascular axis[https://www.sciencedirect.com/science/article/pii/S1878788623000292] and bring the drains out inferiorly, to prevent lymphocele formation.
** Primary closure of the inguinofemoral dissection is usually possible with minimal or no further mobilization of the excision margins.
*** When circumstances demand a large area of inguinal soft tissue sacrifice, primary closure may be obtained by scrotal skin rotation flaps an abdominal wall advancement flap or a myocutaneous flap based on the rectus abdominis or tensor fasciae latae for more extensive defects.
** Suture skin flips to the surface of the exposed musculature to decrease dead space.
***This can minimize the risk of a postoperative fluid collection (i.e., seroma) that may serve as a potential source for infection.
**Reapproximate subcutaneous tissues with 2-0 Vicryl
**Reapproximate skin with 3-0 non-absorbable suture or skin staples[https://www.sciencedirect.com/science/article/pii/S1878788623000292]
**Apply dressings