Decellularized esophageal tubular scaffold microperforated by quantum molecular resonance technology and seeded with mesenchymal stromal cells for tissue engineering esophageal regeneration.

Current surgical options for patients requiring esophageal replacement suffer from several limitations and do not assure a satisfactory quality of life. Tissue engineering techniques for the creation of customized "self-developing" esophageal substitutes, which are obtained by seeding autologous cells on artificial or natural scaffolds, allow simplifying surgical procedures and achieving good clinical outcomes. In this context, an appealing approach is based on the exploitation of decellularized tissues as biological matrices to be colonized by the appropriate cell types to regenerate the desired organs. With specific regard to the esophagus, the presence of a thick connective texture in the decellularized scaffold hampers an adequate penetration and spatial distribution of cells. In the present work, the Quantum Molecular Resonance® (QMR) technology was used to create a regular microchannel structure inside the connective tissue of full-thickness decellularized tubular porcine esophagi to facilitate a diffuse and uniform spreading of seeded mesenchymal stromal cells within the scaffold. Esophageal samples were thoroughly characterized before and after decellularization and microperforation in terms of residual DNA content, matrix composition, structure and biomechanical features. The scaffold was seeded with mesenchymal stromal cells under dynamic conditions, to assess the ability to be repopulated before its implantation in a large animal model. At the end of the procedure, they resemble the original esophagus, preserving the characteristic multilayer composition and maintaining biomechanical properties adequate for surgery. After the sacrifice we had histological and immunohistochemical evidence of the full-thickness regeneration of the esophageal wall, resembling the native organ. These results suggest the QMR microperforated decellularized esophageal scaffold as a promising device for esophagus regeneration in patients needing esophageal substitution.

Evaluation of Gastroesophageal Reflux Disease 1 Year after Esophageal Atresia Repair: Paradigms Lost from a Single Snapshot?

OBJECTIVE: To analyze the findings of both multichannel intraluminal impedance with pH (MII-pH) and endoscopy/histopathology in children with esophageal atresia at age 1 year, according to current recommendations for the evaluation of gastroesophageal reflux disease (GERD) in esophageal atresia. STUDY DESIGN: We retrospectively reviewed both MII-pH and endoscopy/histopathology performed in 1-year-old children with esophageal atresia who were followed up in accordance with international recommendations. Demographic data and clinical characteristics were also reviewed to investigate factors associated with abnormal GERD investigations. RESULTS: In our study cohort of 48 children with esophageal atresia, microscopic esophagitis was found in 33 (69%) and pathological esophageal acid exposure on MII-pH was detected in 12 (25%). Among baseline variables, only the presence of long-gap esophageal atresia was associated with abnormal MII-pH. Distal baseline impedance was significantly lower in patients with microscopic esophagitis, and it showed a very good diagnostic performance in predicting histological changes. CONCLUSIONS: Histological esophagitis is highly prevalent at 1 year after esophageal atresia repair, but our results do not support a definitive causative role of acid-induced GERD. Instead, they support the hypothesis that chronic stasis in the dysmotile esophagus might lead to histological changes. MII-pH may be a helpful tool in selecting patients who need closer endoscopic surveillance and/or benefit from acid suppression.

Anastomotic Strictures after Esophageal Atresia Repair: Incidence, Investigations, and Management, Including Treatment of Refractory and Recurrent Strictures.

Improved surgical techniques, as well as preoperative and postoperative care, have dramatically changed survival of children with esophageal atresia (EA) over the last decades. Nowadays, we are increasingly seeing EA patients experiencing significant short- and long-term gastrointestinal morbidities. Anastomotic stricture (AS) is the most common complication following operative repair. An esophageal stricture is defined as an intrinsic luminal narrowing in a clinically symptomatic patient, but no symptoms are sensitive or specific enough to diagnose an AS. This review aims to provide a comprehensive view of AS in EA children. Given the lack of evidence-based data, we critically analyzed significant studies on children and adults, including comments on benign strictures with other etiologies. Despite there is no consensus about the goal of the luminal diameter based on the patient's age, esophageal contrast study, and/or endoscopy are recommended to assess the degree of the narrowing. A high variability in incidence of ASs is reported in literature, depending on different definitions of AS and on a great number of pre-, intra-, and postoperative risk factor influencing the anastomosis outcome. The presence of a long gap between the two esophageal ends, with consequent anastomotic tension, is determinant for stricture formation and its response to treatment. The cornerstone of treatment is endoscopic dilation, whose primary aims are to achieve symptom relief, allow age-appropriate capacity for oral feeding, and reduce the risk of pulmonary aspiration. No clear advantage of either balloon or bougie dilator has been demonstrated; therefore, the choice is based on operator experience and comfort with the equipment. Retrospective evidences suggest that selective dilatations (performed only in symptomatic patients) results in significantly less number of dilatation sessions than routine dilations (performed to prevent symptoms) with equal long-term outcomes. The response to dilation treatment is variable, and some patients may experience recurrent and refractory ASs. Adjunctive treatments have been used, including local injection of steroids, topical application of mitomycin C, and esophageal stenting, but long-term studies are needed to prove their efficacy and safety. Stricture resection or esophageal replacement with an interposition graft remains options for AS refractory to conservative treatments.

Endoscopic management of esophageal stenosis in children: New and traditional treatments.

Post-esophageal atresia anastomotic strictures and post-corrosive esophagitis are the most frequent types of cicatricial esophageal stricture. Congenital esophageal stenosis has been reported to be a rare but typical disease in children; other pediatric conditions are peptic, eosinophilic esophagitis and dystrophic recessive epidermolysis bullosa strictures. The conservative treatment of esophageal stenosis and strictures (ES) rather than surgery is a well-known strategy for children. Before planning esophageal dilation, the esophageal morphology should be assessed in detail for its length, aspect, number and level, and different conservative strategies should be chosen accordingly. Endoscopic dilators and techniques that involve different adjuvant treatment strategies have been reported and depend on the stricture's etiology, the availability of different tools and the operator's experience and preferences. Balloon and semirigid dilators are the most frequently used tools. No high-quality studies have reported on the differences in the efficacies and rates of complications associated with these two types of dilators. There is no consensus in the literature regarding the frequency of dilations or the diameter that should be achieved. The use of adjuvant treatments has been reported in cases of recalcitrant stenosis or strictures with evidence of dysphagic symptoms. Corticosteroids (either systemically or locally injected), the local application of mitomycin C, diathermy and laser ES sectioning have been reported. Some authors have suggested that stenting can reduce both the number of dilations and the treatment length. In many cases, this strategy is effective when either metallic or plastic stents are utilized. Treatment complications, such esophageal perforations, can be conservatively managed, considering surgery only in cases with severe pleural cavity involvement. In cases of stricture relapse, even if such relapses occur following the execution of well-conducted conservative strategies, surgical stricture resection and anastomosis or esophageal substitution are the only remaining options.

Treatment of esophageal achalasia in children: Today and tomorrow.

BACKGROUND: Esophageal achalasia (EA) is a rare esophageal motility disorder in children. Laparoscopic Heller myotomy (LHM) represents the treatment of choice in young patients. Peroral endoscopic myotomy (POEM) is becoming an alternative to LHM. The aim of this study is to evaluate the effectiveness, safety, and outcomes of POEM vs LHM in treatment of children with EA. METHODS: Data of pediatric patients with EA, who underwent LHM and POEM from February 2009 to December 2013 in two centers, were collected. RESULTS: Eighteen patients (9 male, mean age: 11.6 years; range: 2-17 years) were included. Nine patients (6 male, mean age: 10.7 years; range: 2-16 years) underwent LHM, and the other 9 (3 males, mean age: 12.2 years; range: 6-17 years) underwent POEM procedure. Mean operation time was shorter in POEM group compared with LHM group (62/149 minutes). Myotomy was longer in POEM group than in LHM group (11/7 cm). One major complication occurred after LHM (esophageal perforation). No clinical and manometric differences were observed between LHM and POEM in follow-up. The incidence of iatrogenic gastroesophageal reflux disease was low (1 patient in both groups). CONCLUSIONS: Results of a midterm follow-up show that LHM and POEM are safe and effective treatments also in children. Besides, POEM is a mini-invasive technique with an inferior execution timing compared to LHM. A skilled endoscopic team is mandatory to perform this procedure.

Miniprobe EUS in management of pancreatic pseudocyst.

Pancreatic pseudocysts (PP) arise from trauma and pancreatitis; endoscopic gastro-cyst drainage (EGCD) under endoscopic ultrasonography (EUS) in symptomatic PP is the treatment of choice. Miniprobe EUS (MEUS) allows EGCD in children. We report our experience on MEUS-EGCD in PP, reviewing 13 patients (12 children; male:female = 9:3; mean age: 10 years, 4 mo; one 27 years, malnourished male Belardinelli-syndrome; PP: 10 post-pancreatitis, 3 post-traumatic). All patients underwent ultrasonography, computed tomography and magnetic resonance imaging. Conservative treatment was the first option. MEUS EGCD was indicated for retrogastric cysts larger than 5 cm, diameter increase, symptoms or infection. EGCD (stent and/or nasogastrocystic tube) was performed after MEUS (20-MHz-miniprobe) identification of place for diathermy puncture and wire insertion. In 8 cases (61.5%), there was PP disappearance; one, surgical duodenotomy and marsupialization of retro-duodenal PP. In 4 cases (31%), there was successful MEUS-EGCD; stent removal after 3 mo. No complications and no PP relapse in 4 years of mean follow-up. MEUS EGCD represents an option for PP, allowing a safe and effective procedure.

Endoscopic management of congenital esophageal stenosis.

BACKGROUND/PURPOSE: Congenital esophageal stenosis (CES) is a rare malformation. Endoscopic dilations represent a therapeutic option. This study retrospectively evaluated the efficacy and safety of a conservative treatment of CES. PATIENTS AND METHODS: Patients diagnosed with CES since 1980 by a barium study or endoscopy were reviewed. Endoscopic ultrasonography (Olympus UM-3R-20-MHz radial miniprobe, Olympus Corporation, Tokyo, Japan), available from 2001, allowed for the differential diagnosis of tracheobronchial remnants (TBR) and fibromuscular hypertrophy (FMH) CES. All children underwent conservative treatment by endoscopic dilations (hydrostatic and Savary). RESULTS: Forty-seven patients (20 men) had CES. Fifteen were associated with esophageal atresia; and 8, with Down syndrome. Mean age at the diagnosis was 28.3 months (range, 1 day to 146 months). Symptoms were solid food refusal, regurgitation, vomiting, and dysphagia. Congenital esophageal stenosis was located in the distal esophagus. Endoscopic ultrasonography demonstrated TBR and FMH in 6 patients. One hundred forty-eight dilations in 47 patients were performed. The stenosis healed in 45 (95.7%). Complications were 5 (10.6%) esophageal perforations, hydrostatic (3/32, or 9.3%), and Savary (2/116, or 1.7%). At follow-up, 1 patient with FMH CES and 1 patient with TBR CES required operation for persistent dysphagia. CONCLUSIONS: The conservative treatment yielded positive outcomes in CES. Endoscopic ultrasonography allows for a correct diagnosis of TBR/FMH CES. A surgical approach should be reserved for CES not responsive to dilations.