Gastric antral patch esophagoplasty for extensive corrosive stricture of the esophagus

Bi-layer silk fibroin grafts support functional tissue regeneration in a porcine model of onlay esophagoplasty

Partial circumferential, full thickness defects of the esophagus can occur as a result of organ perforation or tumour resection, or during surgical reconstruction of strictured segments. Complications associated with autologous tissue flaps conventionally utilized for defect repair necessitate the development of new graft options. In this study, bi-layer silk fibroin (BLSF) scaffolds were investigated for their potential to support functional restoration of partial circumferential defects in a porcine model of esophageal repair. Onlay thoracic esophagoplasty with BLSF matrices (~3 x 1.5 cm) was performed in adult swine (N = 6) for 3 months of implantation. All animals receiving BLSF grafts survived with no complications and were capable of solid food consumption. Radiographic esophagrams revealed preservation of organ continuity with no evidence of contrast extravasation or strictures. Fluoroscopic analysis demonstrated peristaltic contractions. Ex vivo tissue bath studies displayed contractile responses to carbachol, electric field stimulation, and KCl while isoproterenol produced tissue relaxation. Histological and immunohistochemical evaluations of neotissues showed a stratified, squamous epithelium, a muscularis mucosa composed of smooth muscle bundles, and a muscularis externa organized into circular and longitudinal layers, with a mix of striated skeletal muscle fascicles interspersed with smooth muscle. De novo innervation and vascularization were observed throughout the graft sites and consisted of synaptophysin-positive neuronal boutons and vessels lined with CD31-positive endothelial cells. The results of this study demonstrate that BLSF scaffolds can facilitate constructive remodeling of partial circumferential, full thickness esophageal defects in a large animal model. Copyright © 2017 John Wiley & Sons, Ltd.

GASTRIC ANTRAL PATCH OESOPHAGOPLASTY FOR IATROGENIC TRACHEO-OESOPHAGEAL FISTULA

Acquired tracheo-oesophageal fistula is a devastating condition, usually occurring as a late manifestation of oesophageal or other thoracic malignancies. In these cases palliation by placement of an oesophageal stent is the preferred option, but management of a large non-malignant fistula is more complex. In many patients in whom primary repair of the defects is not possible oesophagectomy may be seen as the best treatment. We present a case of a large tracheo-oesophageal fistula repaired with a gastric antral patch oesophagoplasty and intercostal muscle flap.

Grafts of porcine intestinal submucosa for repair of cervical and abdominal esophageal defects in the rat

Porcine small intestinal submucosa (SIS) is a cell-free collagen matrix that has demonstrated its ability as scaffold material for constructive remodeling of damaged or missing tissue. The purpose of this study was to evaluate the morphology and function of esophagoplasty in rat using a porcine SIS scaffold for the repair of a semi-circumferential defect in the cervical or in the abdominal esophagus. Sixty-seven rats underwent surgical excision of the anterior wall either of the cervical or of the abdominal esophagus and subsequent repair of the defect with an SIS patch graft. Outcomes of weight gain, signs of dysphagia, hematological and serum chemistry parameters, and barium swallow studies were used to assess the progress of healing and function over a 150-day time period. The grafts were studied for gross changes and histology at predetermined time points. Ninety-four percent of the SIS-treated rats survived, showing no significant differences in survival rate between groups. The grafted animals did well, without signs of dysphagia, and gaining weight. Barium swallow studies showed no evidence of fistula, significant stenosis, or diverticula. No hematological or serum biochemistry abnormalities were found. By 150 days, the SIS graft was replaced with esophageal-derived tissues. Specimens were completely lined by keratinized stratified squamous epithelium and showed complete regeneration of muscle fibers and scarce immunoreactivity for nerve. In the rat model, a patch graft technique using porcine SIS appears to induce esophageal regrowth either in cervical and abdominal esophagus. The repair mechanism occurred through a regenerative healing process.

Esophageal replacement in rat using porcine intestinal submucosa as a patch or a tube-shaped graft

This study compares the efficacy of porcine intestinal submucosa (SIS) patch graft versus SIS-tube graft in esophageal replacement, using a novel esophageal regeneration model. Clinical function, as well as macroscopic and microscopic morphology were evaluated in both SIS-treated groups. We performed semi-circumferential esophageal excision followed by repair of the defect using either a SIS-patch graft (group I) or segmental esophageal excision followed by a SIS-tube interposition graft (group II) in rats. The 28-day survival rate was significantly different between the SIS-treated groups (100% in group I vs. 0% in group II). Unlike the rats in group II, which died within the first postoperative month due to esophageal dysfunction, all surviving animals in group I resumed a normal solid diet within a few days after surgery, without signs of esophageal dysfunction and gained weight. Barium swallow studies showed no evidence of fistula, significant stenosis or diverticula. No hematological or serum biochemistry abnormalities were found. By day 150 the SIS patch was replaced by esophageal-derived tissues. In the rat model, a patch graft technique using SIS appeared to induce esophageal regrowth and provided an initial and long-term satisfactory function, while a tube-shaped graft technique using SIS was unsuccessful.

Save the child's esophagus, Part II: Colic patch repair

PURPOSE

In a previous report, the authors documented the procedures necessary to regain esophageal continuity in infants who had massive disruption of the suture line following esophagoplasty. As a corollary, this study shows the feasibility of preserving the esophagus in older children by using an esophageal patch.

METHODS

Fifteen children ranging in age from 8 months to 16 years at the time of surgery had repair of esophageal strictures or tracheoesophageal fistulae by the use of a vascularized patch rather than esophageal resection and interposition with colon or stomach. The technique of "colonic-patch oesophagoplasty" was described by Hecker and Hollman in 1975. From 1976 to 1995, the authors have used a modification of their procedure in 14 children, and in one patient an intercostal muscle flap was interposed. The technique consists of esophagotomy through the area of stricture with application of a vascularized patch of colon to the resulting defect.

RESULTS

Ten of the patients were boys and four were girls with an additional girl considered for the procedure at 8 months of age. However, during surgery, an intercostal muscle flap interposition was used. Eight children had esophageal stricture caused by lye ingestion; two from anastomotic stricture; two from gastroesophageal reflux; two from recurrent tracheoesophageal fistula; and one from long-term nasogastric intubation. Follow-up showed excellent results in nine patients who had the colic patch operation. All had good swallowing. A tenth patient, the child with the vascularized intercostal muscle flap, is currently eating a regular diet but it has only been 4 months since the operation. However, one of these excellent patients continues to have a small focus of Barrett's esophagus and another one was killed in an automobile accident one year after operation. Three children have good results but with occasional difficulty in swallowing boluses of meat or with continuing reflux. Two patients had poor results and both have undergone reoperation. In one of these children with Down's syndrome and diabetes, the colic patch worked well for 6 years but because of continuing reflux, distal esophageal scarring and obstruction eventually ensued. After reoperation for distal esophageal resection and colic interposition, the patient died of pulmonary failure. The second child with poor results has recently undergone reoperation to extend the esophagotomy through the distal scarred esophagus and to revise the colic patch.

CONCLUSION

The use of a vascular colic patch for treatment of severe esophageal strictures is a viable alternative to esophageal resection and interposition. However, patients with continuing reflux or Barrett's esophagus, or both, may progress with distal esophageal scarring and obstruction and subsequent dilation of the patch. Those patients will require reoperation.