in 1990 , ramirez introduced a new procedure to close abdominal wall hernia ( awh ) , called  components separation technique ( cst )  .
thanks to endoscopy , surgical repair possibilities have risen , reducing the operative trauma and preserving vascular and neuronal anatomical structures .
this report aims to describe a single port endoscopic approach for cst to repair the abdominal wall of a patient undergoing surgery for abdominal aneurysm and already subject to placement of a mesh for awh .
we performed endoscopic - assisted cst , using a single - port access with a gasless technique .
cst is a useful procedure to close large abdominal wall incisional hernia avoiding the use of mesh , notably under contamination , when prosthetic material use is contraindicated .
the endoscopic - assisted cst produces same results than the conventional open separation technique and also minimised tissue trauma that ensures blood supply and prevents postoperative wounds complications .
the described single port method was found to be safe and effective to close large midline abdominal hernias when a primary open or laparoscopic closure is not feasible or when patients have been previously treated with abdominal meshes .
large midline abdominal wall defects reconstruction keeps being a great challenge to surgeon due to technical difficulties and relatively high recurrence rate and morbidity . morbidity and recurrence rate
are high when several conditions coexist : contamination or infection after relaparotomy or after previous abdominal prosthetic repair .
the open or laparoscopic repair by using prosthetic materials is still the most frequent procedure performed , even if contraindicated in contaminated field .
furthermore , patients with this condition sometime need major surgical intervention for neoplasm or aortic diseases . in 1990 , ramirez et al .
introduced a new procedure to close abdominal wall hernia , called the  components separation technique ( cst )  .
this technique is based on autologous tissue reconstruction of the abdominal wall and it is performed through bilateral separation and advancement of muscular layers , in order to bridge the fascial gap , avoiding prosthetic material use .
anterolateral abdominal wall is composed of multiple overlapping muscle layers : the external oblique , the internal oblique , the transversus muscles and the rectus muscles , which are enveloped by the anterior and posterior sheath , fused in the midline at the linea alba . a superficial and deep vascular system form
the blood supply of the abdominal wall structures coming from the epigastric , superior and inferior and the intercostals arteries . described limitations of this technique were complications against the skin and the subcutaneous tissue , caused by surgical interruption of perforating vessels during exposure of oblique muscle . thanks to endoscopy
, the possibility of surgical repair has increased and thereby reducing the operative trauma and preserving the anatomical structures .
lowe et al . demonstrated that the endoscopic - assisted cst minimised tissue trauma and preserved blood supply of the skin , with less morbidity .
this contribution aims to illustrate a different endoscopic approach for cst and to evaluate this technique feasibility in a case of abdominal reconstruction after relaparotomy with mesh section for an abdominal aneurysm repair .
we performed the endoscopic - assisted cst , as reported in the literature , but with an original modification consisting of a  single - port access  gasless technique .
the patient undergoing this procedure needed to repair of an abdominal aortic aneurysm . at the same time
, he presented a large mesh positioned above the muscolar fascia for hernia resulting from a previous surgery for left hemicolectomy .
surgery was performed under general anesthesia , with patient supine and the surgical approach was through a median laparotomy resulting in the total section of the mesh .
the vascular surgeon provided to repair an abdominal aortic aneurysm ( 8 cm long ) , but after the surgery it was impossible closer the muscolar walls and to remove the mesh because of tissue adhesion .
then , in order to close the abdominal incision , a 1.5 cm skin incision was made 5 cm caudally to the arch of the ribs and 5 cm caudo - laterally to the midline [ figure 1 ] .
the operating 30 telescope ( storz seps endoscope ; storz tuttlingen , germany ) , which has a lifting handle and a single 5-mm operating port , was inserted into the subcutaneous plane .
aponeurosis of the external oblique muscle was divided , for a length of 18 cm , using an ace harmonic scalpel ( ethicon endo - surgery , inc . ,
cincinnati , oh ) , 2 cm laterally to the border of rectus abdominis muscle .
the surgeon used the left hand within the abdomen cavity in order to control the fascial border and , during the procedure , to assess abdominal wall release . under video - endoscopic control ,
the external oblique muscle was separated from the internal oblique muscle ( into the avascular plane present between these muscles ) up to anterior axillary line , through blunt dissection .
this step is performed by twisting the scope ( laterally and medially ) , that is manually driven by means of trans - abdominal illumination [ figure 2 ] .
the separation is essential since the fibrous interconnections between both muscles prevent optimal medial shift of the rectus abdominis muscle . at the end of the procedure
, the fascia is closed with a running polydioxanone suture ( psd - loop , johnson and johnson , ltd . ) , without tension and also the edges of the mesh move closer with prolene suture .
a skin incision of 1.5 cm is made 5 cm caudal to the arch of the ribs and 5 cm caudolateral to the midline and the endoscope is inserted the external oblique muscle was separated from the internal oblique muscle in the avascular plane between both muscles to the midaxillary line by blunt dissection with the scope manually driven by means of trans - abdominal illumination
the abdominal wall cst allows ventral defects closure by transposition of the abdominal wall muscles .
cst abdominal wall mobilisation produces a release that is , for each ipsilateral mucles group , about 4 cm long in the upper abdomen , 3 cm in the lower abdomen and 8 cm in the waist . if additional advancement is needed ( rarely ) , the rectus muscle posterior fascia can be freed , allowing 2 cm of additional advancement .
cst is a useful procedure to close a large abdominal wall incisional hernia , avoiding the use of mesh .
it is also particularly notable under contaminate condition , when use of prosthetic material is contraindicated or in complex conditions such as that described in this report .
the patient was prior surgically treated and presented a mesh perfectly adherent whose replacement would have been messy and complex . in a recent randomised controlled trial , comparing the results after cst and prosthetic repair of abdominal wall hernia , cst achieved favorable outcomes . in 2000 , lowe et al . modified the original cst in a minimally invasive technique .
thanks to introduction of endoscopic approach and through the use of a balloon distension in order to create a subcutaneous space and to transect the external oblique aponeurosis , preserving the cutaneous perforating vessels .
later on , some authors demonstrated that the endoscopic - assisted cst produces same results than open conventional separation technique ; moreover , it minimises tissue trauma that ensures the blood supply and it prevents postoperative wound complications
. these procedures result in prolonged operative time , and the use of a single port access with a gasless technique may decrease the operative time .
it seems to us that the described single port method , even if performed in a single case , is safe and effective to close large midline abdominal hernias when a primary open or laparoscopic closure is not feasible , or when patients have been previously treated with abdominal meshes .
 background : in 1990 , ramirez introduced a new procedure to close abdominal wall hernia ( awh ) , called  components separation technique ( cst )  . 
 thanks to endoscopy , surgical repair possibilities have risen , reducing the operative trauma and preserving vascular and neuronal anatomical structures . 
 this report aims to describe a single port endoscopic approach for cst to repair the abdominal wall of a patient undergoing surgery for abdominal aneurysm and already subject to placement of a mesh for awh.methods:we performed endoscopic - assisted cst , using a single - port access with a gasless technique.conclusion:cst is a useful procedure to close large abdominal wall incisional hernia avoiding the use of mesh , notably under contamination , when prosthetic material use is contraindicated . 
 the endoscopic - assisted cst produces same results than the conventional open separation technique and also minimised tissue trauma that ensures blood supply and prevents postoperative wounds complications . 
 the described single port method was found to be safe and effective to close large midline abdominal hernias when a primary open or laparoscopic closure is not feasible or when patients have been previously treated with abdominal meshes . 
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METHODS:
CONCLUSION:
INTRODUCTION
STANDARD TECHNIQUE IMPROVEMENTS
BENEFITS