Intestinal Lengthening Procedures


see also Intestinal Failure

Steps of the Procedure

How is an longitudinal intestinal lengthening and tailoring procedure performed?

The first paper describing a readily reproducible procedure for intestinal lengthening was reported by Bianchi in 1980. The procedure was initially referred to as Intestinal Loop Lengthening [1], then later renamed the Longitudinal Intestinal Lengthening and Tailoring (LILT) procedure, although it is most commonly referred to as the Bianchi procedure. The initial step of the LILT procedure involves the use of blunt dissection to separate the mesentery into two separate leaves, each of which supplies blood to half of the intestine. The intestine is then divided longitudinally either with a surgical stapler or using a hand sewn longitudinal suture closure. This results in two separate loops of intestine each with half the circumference of the original loop. When these two loops are then anastomosed end to end in an isoperistaltic fashion; the result is a doubling of the length as well as a tapering of the diameter of the intestine.

LILT procedure
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Figure from the original paper describing the longitudinal intestinal lengthening and tailoring (LILT) procedure. (Bianchi A. Intestinal loop lengthening--a technique for increasing small intestinal length. J Pediatr Surg 1980;15(2):145-151)

The procedure was modified in 1998 by Chahine and Ricketts[2] to require only one anastomosis by using opposing taperings at each end of the longitudinal staple line. Once the tapered ends are trimmed to the appropriate diameter, the two tapered ends can be anastomosed end-to-end thus restoring intestinal continuity with only one anastomosis. Functionally, the LILT can only be done with relatively uniformly dilated bowel and the surgeon can expect the diameter to be reduced by half and the length to be doubled. Potential risks include leakage from the staple lines or anastomoses, intestinal obstruction and intestinal ischemia due to injury of the fragile mesenteric vasculature during the mesenteric dissection. Continued intestinal dilation is not uncommon as the bowel continues to undergo adaptation.

How is a serial transverse enteroplasty procedure performed?

The first paper describing the serial transverse enteroplasty (STEP) procedure was published by Kim et al in 2003 [3]. This was quickly followed by the first clinical case report [4]. The surgical technique described in these first two papers has remained relatively unchanged over the years. The STEP procedure involves the use of surgical staplers to partially transect the bowel with multiple applications spaced evenly down the length of the bowel from alternating sides to create a zigzag shaped lumen that has a smaller diameter and is longer than the original bowel.

STEP procedure
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This drawing shows the basic elements of the serial transverse enteroplasty (STEP) procedure. The surgical stapler is kept perpendicular to the long axis of the bowel and the bowel is partially transected. This is repeated from alternating and opposite sides until a uniform intestinal lumen is created that is tapered and lengthened compared to the original bowel.

While the stapler firings may come from any angle relative to the mesentery, we prefer to use the 90° and 270º approaches (relative to the mesentery at 0º) and make a mesenteric defect to pass one arm of the stapler through at each staple firing. The length of the staple line and the spacing between staple lines should be determined by the desired intestinal lumen diameter. We generally base this on the size of the normal bowel which varies according to age of the patient. Generally, approximately 2 to 2.5 cm seems to be an appropriate lumen diameter (as measured with the bowel flattened so this is actually half the circumference, not the true diameter). Following completion of the stapler firings, the apex of each staple firing should be sutured as this is a relative weak point due to the presence of a small gap between staple rows at the end of the knife cut. Potential complications include staple line leakage, intestinal obstruction, and stricture.

Intestinal redilation is not uncommon following the LILT or STEP procedures and this can be treated with a STEP after either procedure [4][5][6].


  1. Bianchi A. Intestinal loop lengthening--a technique for increasing small intestinal length. J Pediatr Surg. 1980;15(2):145-51.  [PMID:7373489]
  2. Chahine AA, Ricketts RR. A modification of the Bianchi intestinal lengthening procedure with a single anastomosis. J Pediatr Surg. 1998;33(8):1292-3.  [PMID:9722007]
  3. Kim HB, Fauza D, Garza J, et al. Serial transverse enteroplasty (STEP): a novel bowel lengthening procedure. J Pediatr Surg. 2003;38(3):425-9.  [PMID:12632361]
  4. Kim HB, Lee PW, Garza J, et al. Serial transverse enteroplasty for short bowel syndrome: a case report. J Pediatr Surg. 2003;38(6):881-5.  [PMID:12778385]
  5. Kang KH, Gutierrez IM, Zurakowski D, et al. Bowel re-dilation following serial transverse enteroplasty (STEP). Pediatr Surg Int. 2012;28(12):1189-93.  [PMID:23160903]
  6. Piper H, Modi BP, Kim HB, et al. The second STEP: the feasibility of repeat serial transverse enteroplasty. J Pediatr Surg. 2006;41(12):1951-6.  [PMID:17161180]
Last updated: May 7, 2016