Endoscopic component separation
From SAGES Surgical Wiki
Endoscopic Component Separation
Abdominal wall repair and reconstruction remains a complicated and controversial issue. The component separation technique (CST) was first described by Ramirez1 in 1990 as a means of achieving primary midline closure during ventral hernia repair. Through this external oblique release, the rectus muscle can be medialized (up to 10cm on each side) allowing for tension-free midline approximation. Although the indications are sometimes vague and questions remain regarding the optimal uses of mesh (biologic vs. synthetic vs. not at all), the technique has evolved into a minimally invasive approach to decrease wound morbidity and complication while maintaining the same goals as the open operation.
The open technique involves creation of large skin flaps, typically extending approximately 3cm lateral to the semilunar line. In making such flaps, perforating epigastric vessels to the skin must be divided, thereby compromising skin viability and increasing the possibility of wound complications. The endoscopic technique permits access to the external oblique muscle and aponeurosis without creation of the skin flaps. In other attempts to decrease wound complications, alternative techniques of sparing the periumbilical perforating vessels or tunneled dissection methods have also been described2,3.
Small ventral or umbilical hernias may be repaired primarily with or without mesh reinforcement in some cases. However, this is not applicable to larger hernias as fascial closure may not be achievable without more aggressive maneuvers. Primary fascial closure may allow for decreased seroma formation versus a bridging mesh. Additionally, large sheets of bridging synthetic mesh may be at higher rate of hernia recurrence or infection. Without midline closure of the abdominal wall, abdominal wall function may be compromised and rendered adynamic4. The indications for endoscopic vs. open component separation are largely the same. The latter may allow for somewhat greater fascial release and medialization while the former decreases the likelihood of wound complications.
Different authors suggest slightly different methods of endoscopic components separation; however, the principles remain the same4,5.
Following completion of any necessary intrabdominal procedures (adhesiolysis, bowel resection, removal of hernia sac, etc…) attention is paid to the hernia repair with the myofascial cutaneous flap. A totally laparoscopic approach is sometimes possible depending on what intra-abdominal procedures may be necessary6.
1) An incision is made between in the anterior axillary line between the costal margin and 5cm above it
2) Following exposure and division of the external oblique muscle, an avascular plane is bluntly created between the external and internal oblique muscles (defining the lateral abdominal cavity)
3) This area is expanded using either blunt dissection or a balloon dissector to the level of the external ring
4) The balloon dissector is exchanged for a balloon-tipped trocar
5) The lateral abdominal cavity is insufflated with 10-15mmHg of CO2.
6) An additional 5mm trocar is inserted into the space adjacent to the balloon-tipped trocar (an additional, lower 5mm trocar is sometimes necessary)
7) The external oblique muscle and aponeurosis are divided from the external rib to up to 5cm above the costal margin
8) A drain is sometimes placed into the space
9) The midline fascia is closed (with or without mesh reinforcement)
Mesh overall has been shown to decrease recurrence rates when in the repair of ventral hernias. The use of synthetic mesh in contaminated fields is highly controversial and associated with significant morbidity in the event of infection. Reinforcement with biologic and synthetic mesh (in the intra-peritoneal, retro-rectus, or on-lay position) have all been described with variable results.
Open vs. Endoscopic
The open technique, although an effective means of achieving the goals of fascial closure, suffers from wound complications ranging from the minor to debilitating. Because the endoscopic technique leaves the epigastric skin perforating vessels intact, wound complications are reported as lower. However, the creation of skin flaps does allow for slightly more rectus mobilization. In the porcine model, the endoscopic technique has been shown to give 86% of the release as compared with the open technique4. Although the exact amount of release is variable, either technique will usually afford between 6-10cm of mobility on each side. The rates of wound complication from either method are depending upon indication and patient comorbidity. Wound complication rates in the open technique may be as high as 50%, but generally, the minimally invasive release decreases wound complication rates by at least half5,7. Most common complications are related to infection, seroma, and skin/flap necrosis.
Rates of recurrence are highly dependent upon methods of reinforcement, indications, hernia size, and patient factors. However, recurrence rates for the endoscopic versus open technique appear to be equivalent and have been reported to be as high as 32%7,8.
The minimally invasive technique does require basic endoscopic instrumentation. Although the initial cost of the operation may be more with this method, the difference is marginal and operative times seem roughly equivalent. A greater contribution to the cost seems to come from the use of biologic meshes and the wound morbidities8,9.
1. Ramirez OM, Ruas E, Dellon AL. “Components separation” method for closure of abdominal-wall defects: an anatomic and clinical study. Plast Reconstr Surg. 1990;86(3):519–526.
2. Saulis AS, Dumanian GA. Periumbilical rectus abdominis perforator preservation significantly reduces superficial wound complications in “separation of parts” hernia repairs. Plast Reconstr Surg. 2002;109(7):2275–80; discussion 2281–2.
3. Ko J, Wang E, Salvay D, Paul B, Dumanian G. Abdominal Wall Reconstruction: Lessons Learned From 200“ Components Separation” Procedures. Archives of Surgery. 2009;144(11):1047.
4. Rosen MJ, Williams C, Jin J, et al. Laparoscopic versus open-component separation: a comparative analysis in a porcine model. Am J Surg. 2007;194(3):385–389.
5. Giurgius M, Bendure L, Davenport DL, Roth JS. The endoscopic component separation technique for hernia repair results in reduced morbidity compared to the open component separation technique. Hernia. 2011.
6. Rosen MJ, Fatima J, Sarr MG. Repair of abdominal wall hernias with restoration of abdominal wall function. J Gastrointest Surg. 2010;14(1):175–185.
7. Harth KC, Rosen MJ. Endoscopic versus open component separation in complex abdominal wall reconstruction. Am J Surg. 2010;199(3):342–6; discussion 346–7.
8. Albright E, Diaz D, Davenport D, Roth JS. The component separation technique for hernia repair: a comparison of open and endoscopic techniques. Am Surg. 2011;77(7):839–843.
9. Harth KC, Rose J, Delaney CP, et al. Open versus endoscopic component separation: a cost comparison. Surg Endosc. 2011;25(9):2865–2870.