Stem cell activation during distraction enterogenesis in the murine colon.

PURPOSE: Short bowel syndrome (SBS) is a devastating disease. We have proposed spring-mediated distraction enterogenesis for intestinal lengthening. Colonic lengthening is a potential treatment option for SBS to enhance fluid absorption capacity. We hypothesized that intraluminal spring-mediated colonic lengthening is associated with stem cell proliferation. METHODS: C57BL/6 mice underwent placement of a gelatin-encapsulated compressed or uncompressed nitinol spring in a cecal segment. Animals were given clear liquid diet until postoperative day (POD) 7, followed by regular diet until POD 14. Cecal lengths were measured at euthanasia, and tissue was formalin fixed for histological processing. For Lgr5-GFP mice, immunohistochemistry against GFP was performed to localize Lgr5+ cells within crypts. RESULTS: Significant cecal lengthening with compressed springs and shortening with uncompressed springs were observed on POD 7 and 14. Mucosa of the compressed spring group was significantly thicker on POD 14. The density of Lgr5+ cells within the crypts in the compressed spring groups was higher than that in the uncompressed spring groups on both POD 7 and 14. CONCLUSION: Expandable springs can be used to lengthen the colon in the mouse model. Colonic lengthening was associated with gradual mucosal thickening and correlated with an increased density of stem cells within the crypts.

Distraction enterogenesis in the murine colon.

BACKGROUND/PURPOSE: Distraction enterogenesis with intraluminal spring technology has been successfully used to lengthen segments of murine small intestine. We hypothesized that biocompatible springs could also be used to lengthen murine large intestine. METHODS: Age and weight matched C57BL/6 mice underwent surgical insertion of nitinol spring-loaded capsules into the cecum. Segment lengths were measured at initial spring placement and at euthanasia after 7 and 14 days. Histologic adaptations were evaluated at scarification. RESULTS: Cecal segments loaded with compressed springs lengthened an average of 150%, which was significantly longer than control segments loaded with either empty capsules or uncompressed springs. Muscularis layers tended to be thicker in the compressed spring groups compared to control groups. CONCLUSIONS: Insertion of a compressed nitinol spring into the cecum results in significant colonic lengthening in a mouse model. The ability to increase cecum length serves as proof of concept that distraction enterogenesis technology may be feasibly applied to large intestinal models. The use of distraction enterogenesis technology shows promise for application to clinical models in the treatment of pediatric intestinal disease.

Small surgeries, big smiles: using virtual reality to reduce the need for sedation or general anesthesia during minor surgical procedures.

PURPOSE: Children often require anesthesia for simple diagnostic and therapeutic procedures. The aim of this study was to evaluate the feasibility of using virtual reality (VR) to reduce sedation in children undergoing minor surgical procedures. METHOD: In this prospective, non-randomized clinical trial, pediatric patients at a free-standing children's hospital undergoing hormone implant placement, removal, or exchange were recruited to use VR and local anesthesia instead of procedural sedation or general anesthesia (GA). Patients were enrolled between November 2017 and March 2020, and were compared to historic controls who underwent similar procedures without VR between April 2016 and February 2020. Primary outcome measure was successful procedure completion without sedation or GA. Secondary measures included assessments of pain, fear and anxiety, patient compliance, procedural and recovery times. RESULTS: Twenty-eight patients underwent 29 procedures with VR. Hormone implants (72%), removals (7%), or exchanges (21%) were completed without GA, sedation or IV placement. Procedure lengths and pain scores were similar between VR patients and historic controls, but recovery times were significantly shorter in VR patients (18 vs 65 min, p < 0.001). Participant satisfaction scores were high, with 95% recommending VR to others. CONCLUSIONS: VR is a feasible alternative to sedation or GA for select pediatric patients undergoing minor surgical procedures.

Intestinal adaptation following spring insertion into a roux limb in mice.

BACKGROUND/PURPOSE: Intraluminal springs have recently been shown to lengthen segments of intestine in a process known as distraction enterogenesis. We hypothesized that biocompatible springs could be used to lengthen defunctionalized murine small intestine and would lead to identifiable intestinal adaptations at the molecular level. METHODS: Age and weight matched C57BL/6 mice underwent surgical insertion of nitinol spring-loaded capsules into a Roux limb of jejunum. Segment lengths were measured at initial spring placement and at euthanasia after 14 and 21 days. Histology and gene expression of the Roux limb were evaluated at scarification and compared to untreated control segments. RESULTS: Intestinal segments loaded with compressed springs lengthened an average of 240%, which was significantly longer than control segments loaded with either empty capsules or uncompressed springs. Muscularis thickening was greater in spring-treated mice compared to controls without springs. Crypt depth and Lgr5+ expression was greater in mice that received compressed spring treatments when compared to control groups. CONCLUSIONS: Insertion of a compressed nitinol spring into a Roux limb results in significant intestinal lengthening, smooth muscle thickening, and Lgr5+ expression in a mouse model. The ability to increase small bowel length in a defunctionalized murine model may be used to understand the mechanism of distraction enterogenesis.

Treating children with achalasia using per-oral endoscopic myotomy (POEM): Twenty-one cases in review.

BACKGROUND: Per-oral endoscopic myotomy (POEM), a modern treatment for achalasia, has only recently emerged as an option for pediatric patients. Here we describe and characterize the success of POEM in children with achalasia. METHODS: A single-institution prospective cohort study was performed of patients <18 years old who underwent POEM from 2014 to 2019. Main outcomes were success at one year (Eckardt ≤3), procedure duration, complications, reintervention. RESULTS: The median age of patients (n = 21) was 13 years (range 2-17). Median procedure duration was 92 min (range 52-259) with case duration plateau of 87.4 min and learning rate of 15.5 cases. Intraoperative complications included capnoperitoneum requiring needle decompression and mucosotomy requiring additional clips. One patient experienced chest pain with small capnoperitoneum seen on chest radiography, and three patients had extraluminal carbon dioxide found incidentally on routine radiography. All were managed with observation. Pre- versus 1-month postprocedure Eckardt scores were significantly improved (7 ±â€¯2 versus 1 ±â€¯2, p < 0.0001, and median ±â€¯SD) with 100% symptomatic relief at one year. To achieve this, 13 patients required further dilation(s), one required laparoscopic Heller myotomy, and two required repeat POEM. CONCLUSIONS: POEM is a viable and safe treatment for pediatric patients with achalasia. We demonstrate improvement in symptoms and procedure proficiency with minimal intra- and postoperative complications. TYPE OF STUDY: Prospective cohort study. LEVEL OF EVIDENCE: Level II.

Biomechanical signaling and collagen fiber reorientation during distraction enterogenesis.

Distraction enterogenesis has been extensively studied as a potential treatment for short bowel syndrome, which is the most common subset of intestinal failure. Spring distraction uses an intraluminal axial mechanical force to stimulate the growth and elongation of the small intestine. The tissue close to the distracted intestinal segment may also experience signaling to grow. In this study we examined the effects of distraction enterogenesis at different post-operative days on the thickness of small intestinal layers in the intestine proximal and distal to the distracted segment, as well as how the submucosal collagen fibers were reoriented. It was observed that not only different layers of intestine wall in distracted segment showed thickening due to the applied mechanical force but also adjacent tissues in both distal and proximal directions were impacted significantly where they showed thickening as well. The orientation of collagen fibers in submucosa layer was also significantly impacted due to the mechanical force in both distracted and adjacent tissue. The effect of the applied mechanical force on the main distracted tissue and the radial growth of the adjacent tissue strongly suggest actions of paracrine signaling.