Young Chul Cho

Tuberculous Tracheobronchial Strictures Treated with Balloon Dilation: A Single-Center Experience in 113 Patients during a 17-year Period

PURPOSE To evaluate the safety and effectiveness of balloon dilation in the treatment of tuberculous tracheobronchial strictures (TTBSs) in a series of 113 patients at a single institution. MATERIALS AND METHODS The institutional review board approved the study and waived the requirement to obtain informed consent. Between 1997 and 2014, under bronchoscopic and fluoroscopic guidance, a total of 167 balloon dilation sessions were performed in 113 consecutive patients (14 male and 99 female patients; mean age, 37 years [age range, 17-73 years]), with a range of one to eight sessions per patient (mean, 1.5 sessions). Outcomes were number and/or frequency of balloon dilations, technical success, primary and secondary clinical success, improvement in respiratory status, airway patency rate, and alternative treatment after balloon dilation. A two-tailed paired t test and the Kaplan-Meier method were used to evaluate the improvement in respiratory status and airway patency rate after balloon dilation, respectively. RESULTS Dilation was successful in 82 patients (73%) after single (n = 67) or multiple (n = 15) balloon dilations, with a mean follow-up of 30.3 months. Clinical failure occurred in 31 patients (27%). In these 31 patients, symptoms recurred 1 day to 113 months (mean, 13 months) after repeat balloon dilations. These 31 patients required alternative treatment, including temporary stent placement (n = 12), cutting balloon dilation (n = 12), radiation-eluting balloon dilation (n = 3), and surgery (n = 4). Before, immediately after, and 1 month after the procedure, pulmonary function test results showed significant improvements in mean forced vital capacity (P < .001), forced expiratory volume in 1 second (P = .001), forced expiratory flow in the midexpiratory phase (P = .020), and peak expiratory flow (P = .005). CONCLUSION Balloon dilation of TTBSs is a safe, minimally invasive primary treatment that relieved symptoms in a large percentage of patients (73%). In patients with TTBSs refractory to balloon dilation, temporary stent placement, cutting balloon dilation, or radiation-eluting balloon dilation can be an alternative treatment.

Migration of Retrievable Expandable Metallic Stents Inserted for Malignant Esophageal Strictures: Incidence, Management, and Prognostic Factors in 332 Patients

OBJECTIVE The purpose of this study was to evaluate the incidence, prognostic factors, and secondary management of stent migration in patients with malignant esophageal strictures. MATERIALS AND METHODS A retrospective study was performed in a single tertiary referral university hospital to identify the incidence, management, and prognostic factors for stent migration in 332 consecutive patients with placement of a retrievable expandable metallic stent. Stent migration was classified into four patterns as locations of a migrated stent: pattern I, partially migrated in the proximal direction; pattern II, partially migrated in the distal direction; pattern III, completely migrated into the stomach; and pattern IV, completely migrated into the bowel. RESULTS Stent migration occurred in 42 (12.6%) of 332 patients. Migration was partial (n = 21) or complete (n = 21), and nine (21%), 12 (29%), 11 (26%), and 10 (24%) patients had patterns I, II, III, and IV, respectively. Multivariate analysis identified the following prognostic factors: esophagogastric junction strictures caused by cancer of the gastric cardia (odds ratio 1.330; p = 0.004), patients who underwent anticancer treatment after stent placement (17.514; p < 0.001), and patients with a longer survival time (1.994; p < 0.001). Secondary management was needed for 33 of 42 patients. The strictures in the remaining nine patients improved throughout follow-up. CONCLUSION Stent migration occurs most commonly in patients with cancer of the gastric cardia, patients with longer survival time, and those who underwent anticancer treatment after stent placement. Stent migration is successfully managed by further intervention. Accurate knowledge of the pattern of stent migration is important for successful management.

Full-Thickness Esophageal Perforation After Fluoroscopic Balloon Dilation: Incidence and Management in 820 Adult Patients

OBJECTIVE The purpose of this study is to investigate the incidence, management, and outcomes of esophageal perforation after fluoroscopic balloon dilation in 820 adult patients with esophageal diseases. MATERIALS AND METHODS Between December 1990 and April 2014, a total of 820 adult patients (age range, 21-93 years) underwent 1869 fluoroscopic balloon dilation sessions (mean, 2.3 sessions/patient; range, 1-29 sessions/patient) for esophageal diseases. We retrospectively reviewed the prospectively collected medical records and images of these patients and collected the data of patients who developed esophageal perforations after fluoroscopic balloon dilation. RESULTS During this period, 12 patients (six men and six women; mean age, 51 years; age range, 28-69 years) developed perforations. The perforation rate was 1.5% per patient and 0.6% per dilation. Among the first eight patients, four who were treated with surgery had perforations 2 cm or larger, and the other four who underwent fasting, parenteral alimentation, and treatment with antibiotics had perforations smaller than 2 cm. The last four patients underwent stent placement immediately after the diagnosis, regardless of the perforations size. The median hospital stay was 11.5 days. CONCLUSION Fluoroscopic balloon dilation of esophageal diseases is a safe procedure with a low perforation rate. A perforation size greater than 2 cm is considered large and requires aggressive treatment. Although the number of patients with esophageal perforation we treated is relatively small and further clinical trials are needed, temporary stent placement seems to be an initial choice in the management of esophageal perforations after fluoroscopic balloon dilation.

Preliminary Results of Percutaneous Radiologic Gastrostomy in a Pediatric Population: A Modified Chiba-Needle Puncture Technique With Single Gastropexy

OBJECTIVE The purpose of this study was to evaluate the technical feasibility, safety, and clinical effectiveness of percutaneous radiologic gastrostomy using a modified Chiba-needle puncture technique with single gastropexy in pediatric patients. MATERIALS AND METHODS From July 2006 to December 2013, percutaneous radiologic gastrostomy was performed in 12 children (median age, 21 months; range, 6-46 months). Their stomachs were punctured using a 21-gauge Chiba needle. A single Cope gastrointestinal suture anchor was used for gastropexy, and a tube was inserted through the same tract as the anchor using a 12- or 14-French Dawson-Mueller pigtail drainage catheter. We then evaluated the technical success of the procedure, the number of puncture attempts using a 21-gauge Chiba needle, the procedure time, complications, and treatment of complications. RESULTS Percutaneous radiologic gastrostomy was technically successful in all patients. Only a single puncture attempt was required in 10 patients (83%); two attempts were needed in two patients (17%). The average procedure time was 10 minutes 25 seconds (range, 5 minutes 5 seconds to 25 minutes 24 seconds). Pneumoperitoneum requiring tube exchange occurred in two of the 12 patients (17%). Two patients experienced pain immediately after the procedure. Three patients who had esophagogastric reflux after percutaneous radiologic gastrostomy underwent conversion percutaneous radiologic gastrojejunostomy. CONCLUSION Percutaneous radiologic gastrostomy using a modified Chiba-needle technique with single gastropexy in pediatric patients is technically feasible and safe.

Polydioxanone biodegradable stent placement in a canine urethral model: analysis of inflammatory reaction and biodegradation.

PURPOSE To investigate the inflammatory reaction and perform quantitative analysis of biodegradation after placement of a polydioxanone (PDO) biodegradable stent in a canine urethral model. MATERIALS AND METHODS PDO biodegradable stents were placed in the proximal and distal urethra of nine male mongrel dogs. The dogs were euthanized 4 weeks (group A; n = 3), 8 weeks (group B; n = 3), or 12 weeks (group C; n = 3) after stent placement. The luminal diameter of the stent-implanted urethra was assessed by follow-up retrograde urethrography, and histologic findings were obtained after the dogs were killed. Stents were removed after euthanasia, and their surface morphology and molecular weight were evaluated. Hematologic examination was performed to evaluate inflammatory reaction. RESULTS Stent placement was technically successful in all dogs. The average luminal diameter gradually decreased. The average number of epithelial layers (2.93 vs 4.42; P < .001), the average thickness of papillary projection (0.80 mm vs 1.28 mm; P < .001), and the average thickness of submucosal fibrosis (0.34 mm vs 0.49 mm ; P < .001) were significantly increased in group B versus group A. There were no significant differences between group B and group C. The average inflammatory cell infiltration did not differ significantly in the three groups. Molecular weight losses were 54% in group A and 84% in group B. In group C, PDO stents were completely decomposed. CONCLUSIONS An experimental study in a canine urethral model has demonstrated acceptable inflammatory reaction with gradually increasing granulation tissue but no luminal obstruction within 12 weeks.

Radiation-induced esophageal strictures treated with fluoroscopic balloon dilation: clinical outcomes and factors influencing recurrence in 62 patients:

Background Balloon dilation is safe and effective for the treatment of radiation-induced esophageal stricture (RIES), with favorable short-term and mid-term outcomes; however, few reports of long-term outcomes exist. Few studies have evaluated factors associated with recurrence after balloon dilation. Purpose To evaluate the long-term outcome of balloon dilation in patients with RIES and to identify factors associated with stricture recurrence. Material and Methods The medical records of 62 consecutive patients who had undergone fluoroscopic balloon dilation for RIES at our institution between December 1998 and June 2016 were reviewed. Results One hundred and twenty balloon dilation sessions were performed in 62 patients (mean = 1.9 sessions per patient). Clinical success was achieved in 53 (86%) patients after single (n = 37) or multiple (n = 16) dilation sessions. Complications occurred in 27% of the dilation sessions. The primary patency rates at one, two, three, and five years were 60%, 56%, 52%, and 52%, respectively. Secondary patency rates at one, two, three, and five years were 87%, 85%, 85%, and 80%, respectively. Multivariate logistic regression analysis identified an interval from radiation therapy (RT) to stricture of ≥6 months (hazard ratio [HR] = 0.205; P < 0.001), strictures located at the cervical esophagus (HR = 5.846; P < 0.001), and stricture length of ≥2 cm (HR = 2.923; P = 0.006) as significant predictors of recurrence. Conclusion Despite the high incidence of ruptures and recurrences, fluoroscopic balloon dilation is valuable as an initial therapeutic option for patients with RIES.

Fluoroscopic removal of retrievable self-expandable metal stents in patients with malignant oesophageal strictures: Experience with a non-endoscopic removal system

AbstractObjectivesTo evaluate clinical outcomes of fluoroscopic removal of retrievable self-expandable metal stents (SEMSs) for malignant oesophageal strictures, to compare clinical outcomes of three different removal techniques, and to identify predictive factors of successful removal by the standard technique (primary technical success).MethodsA total of 137 stents were removed from 128 patients with malignant oesophageal strictures. Primary overall technical success and removal-related complications were evaluated. Logistic regression models were constructed to identify predictive factors of primary technical success.ResultsPrimary technical success rate was 78.8 % (108/137). Complications occurred in six (4.4 %) cases. Stent location in the upper oesophagus (P=0.004), stricture length over 8 cm (P=0.030), and proximal granulation tissue (P<0.001) were negative predictive factors of primary technical success. If granulation tissue was present at the proximal end, eversion technique was more frequently required (P=0.002).ConclusionsFluoroscopic removal of retrievable SEMSs for malignant oesophageal strictures using three different removal techniques appeared to be safe and easy. The standard technique is safe and effective in the majority of patients. The presence of proximal granulation tissue, stent location in the upper oesophagus, and stricture length over 8 cm were negative predictive factors for primary technical success by standard extraction and may require a modified removal technique.Key Points• Fluoroscopic retrievable SEMS removal is safe and effective. • Standard removal technique by traction is effective in the majority of patients. • Three negative predictive factors of primary technical success were identified. • Caution should be exercised during the removal in those situations. • Eversion technique is effective in cases of proximal granulation tissue.

Fluoroscopic-guided stent placement in failed tentative endoscopic approaches to malignant gastroduodenal obstructions

Background Fluoroscopic or endoscopic placement of metallic stents is used as a safe, non-surgical, palliative treatment option for malignant gastroduodenal obstructions. However, endoscopic stent placement is not always feasible, due to the tight or tortuous stricture of the obstructed area and insufficient visualization of the stomach due to remnant food material. Purpose To assess the technical feasibility and clinical outcomes of fluoroscopic-guided stent placement in malignant gastroduodenal obstructions following the technical failure of endoscopic stent placement. Material and Methods In all, 19 patients (14 men, 5 women; age range, 36–85 years) were referred due to technical failures of tentative endoscopic stent placement. Indications were failure to pass the guide wire through the obstruction (n = 13), failure to reach the stricture lesion due to short endoscope (n = 5), and acute angulation of the stricture lesion (n = 1). Data were retrospectively collected regarding the technical and clinical success of the fluoroscopy, the dysphagia score before and after stent placement, and major complications and their management. Results Fluoroscopic stent placement was technically successful in 15/19 patients (79%). Failures were due to complete obstruction (n = 3) and acute angulation of the stricture lesion (n = 1). Clinical success was achieved in all 15 patients with successful stent placement. The dysphagia score significantly improved after stent placement (P < 0.001). Complications occurred in 4/15 patients (27%), including tumor overgrowth (n = 2), stent collapse (n = 1), and jaundice (n = 1). Conclusion Fluoroscopic stent placement in malignant gastroduodenal obstructions following a technical failure of endoscopic stent placement is technically feasible and has an acceptable clinical outcome.

In Vivo Fluorescence Microendoscopic Monitoring of Stent-Induced Fibroblast Cell Proliferation in an Esophageal Mouse Model

PURPOSE To evaluate the feasibility of self-expanding metal stent (SEMS) placement and fluorescence microendoscopic monitoring for determination of fibroblast cell proliferation after stent placement in an esophageal mouse model. MATERIALS AND METHODS Twenty fibroblast-specific protein (FSP)-1 green fluorescent protein (GFP) transgenic mice were analyzed. Ten mice (Group A) underwent SEMS placement, and fluoroscopic and fluorescence microendoscopic images were obtained biweekly until 8 weeks thereafter. Ten healthy mice (Group B) were used for control esophageal values. RESULTS SEMS placement was technically successful in all mice. The relative average number of fibroblast GFP cells and the intensities of GFP signals in Group A were significantly higher than in Group B after stent placement. The proliferative cellular response, including granulation tissue, epithelial layer, submucosal fibrosis, and connective tissue, was increased in Group A. FSP-1-positive cells were more prominent in Group A than in Group B. CONCLUSIONS SEMS placement was feasible and safe in an esophageal mouse model, and proliferative cellular response caused by fibroblast cell proliferation after stent placement was longitudinally monitored using a noninvasive fluorescence microendoscopic technique. The results have implications for the understanding of proliferative cellular response after stent placement in real-life patients and provide initial insights into new clinical therapeutic strategies for restenosis.

Overlapping self-expandable metallic stent for palliation of a long (>10 cm) malignant gastroduodenal obstruction

Background Self-expandable metallic stent (SEMS) placement is a well-established palliative treatment approach for malignant gastroduodenal obstruction. In patients with a long (>10 cm) stricture, multiple stents placed in an overlapping fashion are often required. Purpose To investigate the outcomes of overlapping SEMS placement for the palliative treatment of malignant gastroduodenal obstruction in patients with a long (>10 cm) stricture. Material and Methods The medical records of 40 patients who underwent fluoroscopic overlapping SEMS placement for malignant gastroduodenal obstruction due to a long (>10 cm) stricture were reviewed. Results The technical and clinical success rates were 100% and 65.0%, respectively. The mean length of the stricture was 17.0 ± 4.7 cm and the mean number of stents placed in each patient was 2.2 ± 0.5. Metastatic cancer (odds ratio [OR], 0.315; P = 0.018), Eastern Cooperative Oncology Group (ECOG) score ≥3 (OR, 0.018; P = 0.006), and carcinomatosis with ascites (OR, 0.025; P = 0.017) were independent predictors of poor clinical success. The rates of minor and major complications were 27.5% and 2.5%, respectively. The median stent patency and survival were 33 days (interquartile range [IQR], 19–60 days) and 35 days (IQR, 19–73 days), respectively. An ECOG score ≥3 was an independent predictor of a poor survival outcome (hazard ratio, 4.681; P < 0.001). Conclusion Overlapping SEMS placement may be safe and effective for the palliative treatment of malignant gastroduodenal obstruction in patients with a long (>10 cm) stricture.