Yong Fan 1,2 Ho-Young Song 1 Jin Hyoung Kim 1 Jung-Hoon Park 1 Jinoo Kim 1 Hwoon-Yong Jung 3 Sung-Bae Kim 3 Heuiran Lee 4

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1 Vascular and Interventional Radiology Original Research Fan et al. Balloon Dilation of Malignant Esophageal Strictures Vascular and Interventional Radiology Original Research Yong Fan 1,2 Ho-Young Song 1 Jin Hyoung Kim 1 Jung-Hoon Park 1 Jinoo Kim 1 Hwoon-Yong Jung 3 Sung-Bae Kim 3 Heuiran Lee 4 Fan Y, Song HY, Kim JH, et al. Keywords: balloon dilation, esophageal rupture, malignant esophageal strictures DOI: /AJR Received January 10, 2011; accepted after revision May 18, This study was supported by a grant of the Korean Health Technology R&D Project, Ministry for Health, Welfare & Family Affairs. 1 Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap 2-dong, Songpa-gu, Seoul , Republic of Korea. Address correspondence to H. Y. Song (hysong@amc.seoul.kr). 2 Department of Radiology, Haihe Hospital, Tianjin, China. 3 Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Songpa-gu, Seoul, Republic of Korea. 4 Department of Microbiology, Bio-Medical Institute of Technology, University of Ulsan College of Medicine, Asanbyeongwon-gil, Songpa-gu, Seoul, , Korea. AJR 2012; 198: X/12/ American Roentgen Ray Society Evaluation of the Incidence of Esophageal Complications Associated With Balloon Dilation and Their Management in Patients With Malignant Esophageal Strictures OBJECTIVE. The objective of this study was to investigate the incidence of esophageal complications associated with balloon dilation and their management in patients with malignant esophageal strictures. MATERIALS AND METHODS. Fluoroscopically guided esophageal balloon dilation was performed in 89 patients with malignant esophageal strictures during a period of 15 years. Inclusion criteria were patients with unresected esophageal or gastric carcinoma showing short-segment stricture ( 4 cm) at the esophagogastric junction; patients who had previously received chemotherapy, radiation therapy, or both to manage malignant strictures; or patients who were scheduled for chemotherapy or radiation therapy to manage malignant strictures. Of these patients, 72 had esophageal cancer and 17 had stomach cancer. Esophageal rupture was categorized as intramural, transmural, or transmural with mediastinal leakage. RESULTS. A total of 120 procedures were performed, with each patient undergoing one to four procedures. Esophageal rupture occurred in 13 patients (15%): eight with intramural rupture, four with transmural rupture, and one with transmural rupture with mediastinal leakage. Improvements in dysphagia score were observed in 76 of 89 patients (85%) after balloon dilation. All esophageal ruptures were detected immediately after the procedure. Intramural and transmural ruptures were treated conservatively, whereas transmural rupture with mediastinal leakage was treated by temporary stent placement. CONCLUSION. The overall prevalence of esophageal rupture was 15%. All intramural and transmural ruptures were successfully managed conservatively, whereas transmural rupture with mediastinal leakage was treated by temporary stent placement. We found no relationship between rupture incidence and balloon diameter. M alignant strictures of the esophagus and esophagogastric junction may lead to severe dysphagia, malnutrition, cachexia, and aspiration of food [1]. Most cases of malignant dysphagia are caused by carcinomas of the esophagus and gastric cardia that are unresectable at presentation and for which palliative treatment is the only option [2]. The optimal palliative treatment of patients with advanced malignant strictures of the esophagus and esophagogastric junction has not yet been determined. Balloon dilation is a simple, safe, and economic option for the nonsurgical management of dysphagia [3]. Since the first successful treatment of esophageal strictures with a Grüntzig-type balloon catheter in 1981 [4], fluoroscopically guided balloon dilation has become a common treatment for benign esophageal strictures associated with underlying abnormalities and conditions, such as rings, webs, and achalasia, as well as for peptic, postsurgical, postsclerotherapeutic, and corrosive strictures [5 13]. In addition to being effective, balloon dilation has been associated with substantially lower morbidity and mortality rates than surgical correction or traditional dilation such as bougienage. Few reports to date have described the use of fluoroscopically guided balloon dilation for malignant esophageal strictures. Although stent placement is generally regarded as the most effective method for managing malignant esophageal strictures [14 17], complications frequently occur, including reflux esophagitis, stent migration, tracheal compression, and esophageal perforation and obstruction; moreover, these complications may occur more frequently when stents are placed in the upper esophagus and at the esophagogastric junction [18]. Because of technical difficulties in stent placement, this procedure can AJR:198, January

2 Fan et al. be troublesome in some patients. The acute angulation of the esophagogastric junction may also hinder successful stent placement. Furthermore, patients who have been treated with radiation therapy or chemotherapy before stent placement have a higher rate of life-threatening complications such as perforation, bleeding, and tracheoesophageal fistulas and have a higher mortality rate after stent placement [2, 19]. To overcome these obstacles, we attempted balloon dilation in patients with shortsegment narrowing at the esophagogastric junction, followed by either chemotherapy for adenocarcinoma or chemoradiation therapy for squamous cell carcinoma. Balloon dilation was also attempted in patients with recurrence of stricture after chemoradiation therapy for esophageal cancer. Esophageal complications are still critical complications during fluoroscopically guided balloon dilation, such as bleeding and severe pain, especially esophageal rupture. Although many reports have described esophageal rupture and other complications occurring after balloon dilation, few studies have focused on malignant strictures. We therefore assessed the incidence of esophageal complications caused by balloon dilation and their management in patients with malignant esophageal strictures. Materials and Methods Informed consent for balloon dilation was obtained from each patient, and our institutional review board approved this retrospective study. From September 1994 to October 2009, 89 patients with dysphagia due to malignant strictures (78 men, 11 women; mean age, 64 years; range, years) were referred to the interventional radiology department for balloon dilation. Inclusion criteria were patients with unresected esophageal or gastric carcinoma showing short-segment stricture ( 4 cm) at the esophagogastric junction; patients who had previously received chemotherapy, radiation therapy, or both to manage malignant strictures; or patients who were scheduled for chemotherapy or radiation therapy to manage malignant strictures. Exclusion criteria were mildly symptomatic patients in whom an adult-size endoscope could be passed through the stricture; clinical evidence of perforation, peritonitis, or severe coagulopathy; and evidence of small-bowel obstruction. Swallowing capacity was scored to assess clinical improvement as follows: 0, regular diet; 1, ability to swallow some but not all solids; 2, ability to swallow soft diet; 3, ability to swallow liquids only; and 4, complete dysphagia [20]. No. of Strictures Cervical Upper Middle Fig. 1 Bar graph shows distribution of level of esophageal strictures. 15 Lower Esophagograstric Junction All diagnoses were established after review of each patient s history and esophagography and endoscopic biopsy results. Strictures were secondary to carcinoma of the esophagus in 72 patients and to gastric adenocarcinoma involving the esophagogastric junction in 17 patients. Stricture severity and length were evaluated by barium esophagography before balloon dilation. The mean length of the esophageal strictures was 19 mm (range, 7 38 mm) excluding the stricture in a patient with corrosive esophagitis. Eight strictures were located at the cervical esophagus; 12, at the upper thoracic esophagus; 21, at the middle thoracic esophagus; 15, at the lower thoracic esophagus; and 33, at the esophagogastric junction (Fig. 1). During balloon dilation, each patient was instructed either to say Stop or to lift his or her hand when the pain became intolerable. The pharynx was topically anesthetized using an aerosol spray. Neither sedative nor general anesthesia was used. Each patient swallowed a small amount of water-soluble radiopaque contrast medium (iopromide [Ultravist, Bayer Schering Pharma]) to opacify the narrowed esophageal lumen. Under fluoroscopic guidance (Artis, Siemens Healthcare), a inch angled hydrophilic guidewire (Radifocus Wire, Terumo) was inserted into the patient s mouth, through the stricture, and into the distal part of the esophagus or stomach for stability during the procedure. A deflated high-pressure balloon catheter (15 20 mm in diameter and 3 8 cm long; XXL Esophageal, Boston/Scientific; or Maxi LD, Cordis-Johnson & Johnson) was passed over the guidewire to a position astride the stricture. The deflated balloon was slowly inflated with diluted, water-soluble contrast medium until the waist disappeared or the inflation force reached 10 atm ( Pa). The balloon was considered correctly positioned when its waist was in the center of the stricture segment. A picture was taken to measure the diameter of the waist. Afterward, the balloon was slowly inflated until the waist disappeared from the balloon contour. The balloon was usually fully inflated for 30 seconds. After removal of the balloon catheter, esophagography using water-soluble contrast medium was performed to determine the luminal diameter and whether any procedural complications such as esophageal rupture had occurred. Patients were allowed a soft-food diet 1 hour after the procedure and were encouraged to resume intake of solid food as soon as possible. Of the 89 patients, 18 patients had an unresected stricture showing a short segment at the esophagogastric junction including six patients with esophageal carcinoma and 12 patients with gastric carcinoma. Fifty-seven patients had previously received chemotherapy, radiation therapy, or both including 13 patients who received chemotherapy, 15 who received radiation therapy (total dose, 6000 cgy), and 29 who received both (Table 1). Fourteen patients were scheduled for chemotherapy or radiation therapy. All patients underwent follow-up esophagography 1 month after the procedure to verify the status of the stricture and to assess swallowing capacity. Patients were encouraged to visit the outpatient clinic if symptoms recurred. The mean follow-up period was 12.4 weeks (range, 4 42 weeks). Esophageal rupture was defined as leakage of contrast medium through the mucosal layer and was classified according to the movement of the leaked contrast medium into three types. Type 1 consisted of an intramural esophageal rupture, as shown by natural drainage of leaked contrast medium back into the esophageal lumen; type 2 consisted of a well-contained transmural rupture, as shown by localization of leaked contrast medium without any spillage into the mediastinum; and type 3 consisted of a transmural rupture, as shown by free spillage of leaked contrast medium into the mediastinum, pleura, or peritoneum [21]. The possible association between balloon size and the incidence of esophageal rupture was AJR:198, January 2012

3 Balloon Dilation of Malignant Esophageal Strictures TABLE 1: Data About 13 Patients With Esophageal Rupture Patient Balloon Dimensions Balloon Diameter Diet No. Age (y) Sex Cause of Stricture Stricture Location Diameter (mm) Length (cm) (mm)/waist Diameter (mm) (%) Rupture Type a Before Dilation After Dilation 1 67 M Esophageal cancer Lower thoracic esophagus /10.25 (195.03) 1 Liquid Soft 2 58 M Esophageal cancer Cervical esophagus /10.77 (185.71) 2 Liquid Soft 3 51 M Esophageal cancer Cervical esophagus /12.74 (157.02) 1 Soft Soft 4 68 M Esophageal cancer Lower thoracic esophagus /10.01 (199.76) 1 Soft Most 5 66 M Stomach cancer Esophagogastric junction /18.50 (108.08) 1 Liquid Most 6 61 M Esophageal cancer Middle thoracic esophagus /7.64 (196.33) 1 Liquid All 7 66 M Esophageal cancer Middle thoracic esophagus /7.15 (209.71) 2, 1 Liquid Soft 8 61 M Esophageal cancer Esophagogastric junction /7.99 (187.69) 1 Soft Most 9 65 M Esophageal cancer Middle thoracic esophagus /8.94 (223.63) 2 Aphagia Aphagia M Esophageal cancer Middle thoracic esophagus /4.32 (347.37) 1 Liquid Soft M Esophageal cancer Upper thoracic esophagus /11.59 (172.61) 2 Aphagia Liquid M Esophageal cancer Esophagogastric junction /5.62 (356.07) 3 Soft Most M Esophageal cancer Middle thoracic esophagus Soft Soft a Esophageal rupture was defined as leakage of contrast medium through the mucosal layer and was classified according to the movement of the leaked contrast medium into three types: type 1, an intramural esophageal rupture, as shown by natural drainage of leaked contrast medium back into the esophageal lumen; type 2, a well-contained transmural rupture, as shown by localization of leaked contrast medium without any spillage into the mediastinum; and type 3, a transmural rupture, as shown by free spillage of leaked contrast medium into the mediastinum, pleura, or peritoneum. evaluated by measuring the diameter of the balloon and the waist on the same image (Fig. 2) using multimedia software (Motic Images Plus 2.0 ML, Motic China Group). Patients were divided into two groups: those with and those without rupture. The ratio of balloon diameter to waist diameter was calculated in both groups and compared using the Student t test, which was performed using statistics software (SPSS, version 17.0, SPSS). The Fisher exact test was performed to compare the results for 20- and 15-mm-diameter dilatation balloons using the same statistics package. A p < 0.05 was defined as statistically significant. Results The 89 patients underwent a total of 120 balloon procedures, with each patient undergoing one to four procedures. No technical failure occurred. During 120 balloon dilation procedures, patients in 17 procedures (17/120, 14%) prohibited the procedure when the pain became intolerable. For these procedures, we stopped inflating the balloon even though the balloon was incompletely dilated. There was not severe bleeding in this group; bleeding around the balloon was always minimal. Esophageal rupture was observed in 13 of the 89 patients (15%), 12 of 72 with esophageal cancer (17%) and one of 17 with gastric cancer (6%), and in 14 of the 120 procedures (12%). Eight patients (9%) experienced intramural (type 1) ruptures (Fig. 3), four (4%) experienced transmural (type 2) ruptures (Fig. 4), and one (1%) experienced a transmural rupture with mediastinal leakage (type 3). Nine of 14 esophageal ruptures occurred during the first procedure; three, during the second procedure; and two, during the third procedure, including a patient with two ruptures who underwent a total three procedures. Esophageal rupture was observed in seven of the 57 patients (12%) who had undergone previous chemotherapy, radiotherapy, or both and six of the 32 patients (19%) who had not undergone previous treatment. All intramural and transmural ruptures were conservatively treated by fasting and parenteral alimentation for 5 7 days. Patients with transmural ruptures were also treated with antibiotics. One-month followup esophagograms showed that all type 1 and type 2 ruptures had healed successfully without the need for surgery and with no treatment-related deaths. The patient who experienced the type 3 rupture was a 65-year-old man with a shortsegment stricture involving the gastroesophageal junction who experienced dysphagia due to esophageal squamous cell carcinoma. During chemotherapy, the dysphagia worsened, and he underwent dilation with a balloon catheter (20 80 mm) (Fig. 5A). During the first session, the patient complained of severe pain, and the balloon was incompletely inflated. After the first session, leakage of water-soluble contrast medium into the mediastinum from the esophagogastric junction was observed, suggesting a type 3 rupture Fig. 2 Radiograph shows diameter of fully inflated balloon and diameter of balloon waist before balloon inflation in patient with malignant esophageal stricture. AJR:198, January

4 Fan et al. (Figs. 5B and 5C). A retrievable polytetrafluoroethylene-covered stent (18 60 mm; Niti-S Esophageal Covered Stent, Taewoong) was inserted to occlude the leakage (Fig. 5D). The patient subsequently received chemotherapy and radiation therapy. Three weeks after stent placement, the stent was successfully removed without complications. Esophagograms obtained immediately, 1 week, and 1 month after stent placement showed that the leakage had healed completely and the stricture had improved (Fig. 5E). The 89 patients showed an overall improvement in mean dysphagia score from 2.83 to 1.57 (p = ). However, dysphagia persisted in 10 patients and worsened in Fig. 3 Type 1 rupture in 61-year-old man with esophageal cancer (patient 6 in Table 1). A, Esophagogram shows stricture in middle part of esophagus. B, Dilation with balloon 15 mm in diameter and 6 cm long. Notice waist was resistant to dilation. C, Full inflation of balloon. D, Esophagogram obtained using contrast medium immediately after balloon dilation shows intramural rupture (type 1, arrow). E, Follow-up esophagogram obtained 1 month after balloon dilation shows widened lumen and healing of esophageal rupture. Fig. 4 Type 2 rupture in 58-year-old man with esophageal cancer (patient 11 in Table 1). A, Esophagogram shows stricture in upper part of esophagus. B, Dilation with balloon 20 mm in diameter and 6 cm long. Notice waist was resistant to dilation. C, Full inflation of balloon. D, Esophagogram obtained using contrast medium immediately after balloon dilation shows transmural rupture (arrows) without mediastinal spillage (type 2). E, Esophagogram obtained 1 week after balloon dilation shows no barium leakage and improvement of esophageal stricture (arrow). F, Follow-up esophagogram 1 month after balloon dilation shows healing of esophageal rupture. Fig. 5 Type 3 rupture in 65-year-old man with esophageal cancer (patient 12 in Table 1). A, Dilation with balloon 20 mm in diameter and 8 cm long. Notice waist (arrow) was resistant to dilation. B, Incomplete inflation of balloon (arrow). C, Esophagogram obtained using contrast medium immediately after balloon dilation shows leakage of contrast medium (arrows) into mediastinum (type 3). D, Esophagogram obtained after stent placement shows no barium leakage. E, Esophagogram obtained immediately after stent removal shows healing of esophageal rupture (arrow). two. One patient underwent a second balloon procedure 19 days after the first procedure because of early restenosis; this patient underwent a total of four sessions of balloon dilation, resulting in clinical improvement. Ten patients with restenosis underwent stent placement, whereas two underwent gastrostomy from 1 week to 6 months after balloon dilation to relieve dysphagia. The 120 procedures involved 60 balloons 20 mm in diameter, 20 balloons 18 mm in diameter, four balloons 16 mm in diameter, 34 balloons 15 mm in diameter, and one each 25 mm and 14 mm in diameter. The 14 procedures that resulted in rupture involved 10 balloons 20 mm in diameter and four balloons 15 mm in diameter. There was no statistically significant difference in balloon diameter between procedures with rupture and those without rupture (p > 0.05). We divided the 120 procedures into two groups: 14 with rupture and 106 without rupture. Thirteen procedures (13/14, 93%) were performed in the rupture group compared with 82 procedures (82/106, 77%) in the nonrupture group. The mean ratio of balloon waist to fully expanded balloon diameter was 200% ± 58% (SD; range, %) in the group with out rupture and 208% ± 74% (range, %) in the group with rupture, a difference that was not statistically significant (p > 0.05). 216 AJR:198, January 2012

5 Balloon Dilation of Malignant Esophageal Strictures Discussion We found that the technical success rate, defined as successful balloon dilation and improvement of luminal diameter as shown by immediate postprocedure esophagography, was 100%, which is similar to the rates reported in previous studies of balloon dilation of benign esophageal strictures [22, 23]. The clinical success rate, defined as improved food intake and reduced dysphagia within 1 month of balloon dilation, was 87% (77/89). During 14% of the procedures, the patient had severe chest pain that would disappear when we stopped inflating the balloon. No severe bleeding occurred in this group. We found that 13% of our patients had intramural (type 1) or well-contained transmural (type 2) esophageal ruptures, whereas one (1%) had a transmural rupture with mediastinal spillage (type 3). In comparison, the rupture rate during balloon dilation of corrosive strictures was 32%, indicating that fluoroscopically guided balloon dilation of corrosive esophageal stricture requires extra caution [24], and the rupture rate during balloon dilation of both benign and malignant strictures was 12% [21]. Although improved outcomes have been reported because these patients were treated with antibiotics, better nutritional support, and better postoperative care, the management of patients with esophageal rupture, especially type 3, remains difficult. Perforation after esophageal dilation usually occurs at the site of the stricture. The risk of perforation after balloon dilation is approximately 3%, but this risk is higher in patients with tumors who were previously treated with chemotherapy, radiation therapy, or laser therapy [18, 25]. Esophageal balloon dilation should be performed more cautiously in patients who have a recently healed perforation or have recently undergone upper gastrointestinal surgery, with continuing esophageal perforation being an absolute contraindication to esophageal balloon dilation [25]. In previous studies, patients, especially those with esophageal strictures caused by corrosive agents, were started with a small-diameter balloon that was gradually increased up to 20 mm if the patient tolerated the procedure well [14, 21]. In contrast, we found that the rupture rate was not related statistically to balloon diameter. Alternatively, dilation with a single large-diameter balloon (< 15 mm) or incremental dilation with balloons greater than 3 mm may be safe in patients with simple esophageal strictures [26]. Iatrogenic esophageal perforation is associated with high morbidity and mortality rates. The recommended treatment of esophageal perforation is surgical repair [27], which should be performed rapidly once the diagnosis is confirmed. However, patients with perforations diagnosed and treated surgically within 24 hours continue to have a mortality rate of between 12% and 36% [28]. Placement of covered stents was recently shown to be a safe and effective therapeutic modality for esophageal perforations after surgery or procedures [29, 30]. To our knowledge, only a few reports have explored the effectiveness of treating malignant esophageal perforations with retrievable stents. The stent removal procedure would be difficult because the removal methods described in those reports used general anesthesia and esophagoscopy. Although stent placement is associated with more complications due to frequent stent migration, gastroesophageal reflux, and aspiration pneumonia, temporary placement of covered retrievable expandable metallic stents with concurrent radiation therapy for patients with esophageal carcinoma can reduce complications. Our experience [24, 31] has indicated that temporary stent placement with concurrent chemotherapy and radiation therapy may be used in the palliative treatment of malignant esophageal strictures. In those studies [24, 31], our results showed that balloon dilation was not more effective for the treatment of esophageal stricture than placement of a covered stent, including temporary and permanent stent placement. The mean dysphagia scores were reduced from 3.04 before treatment to 1.29 after balloon dilation and from 3.04 before treatment to 1.17 after stent placement [31]; no significant difference was shown. In conclusion, balloon dilation of esophageal malignant strictures was effective and safe with an acceptable complication rate. Ruptures, even type 3 ruptures, could be managed effectively. References 1. Vermeijden JR, Bartelsman JF, Fockens P, Meijer RC, Tytgat GN. Self-expanding metal stents for palliation of esophagocardial malignancies. Gastrointest Endosc 1995; 41: Adler DG, Baron TH. Endoscopic palliation of malignant dysphagia. Mayo Clin Proc 2001; 76: Stewart ET, Miller WN, Hogan WJ, Dodds WJ. Desirability of roentgen esophageal examination immediately after pneumatic dilatation for achalasia. Radiology 1979; 130: London RL, Troman BW, Di Marino AJ Jr, et al. Dilatation of severe esophageal strictures by an inflatable balloon catheter. Gastroenterology 1981; 80: Reed CE. Pitfalls and complications of esophageal prosthesis, laser therapy, and dilation. Chest Surg Clin N Am 1997; 7: Hair CS, Devonshire DA. Severe hyperplastic tissue stenosis of a novel biodegradable esophageal stent and subsequent successful management with high-pressure balloon dilation. Endoscopy 2010; 42:E132 E Hirano I. Dilation in eosinophilic esophagitis: to do or not to do? Gastrointest Endosc 2010; 71: Bravi I, Nicita MT, Duca P, et al. A pneumatic dilation strategy in achalasia: prospective outcome and effects on oesophageal motor function in the long term. Aliment Pharmacol Ther 2010; 31: Pastor AC, Mills J, Marcon MA, Himidan S, Kim PC. A single center 26-year experience with treatment of esophageal achalasia: is there an optimal method? J Pediatr Surg 2009; 44: Siersema PD, de Wijkerslooth LRH. Dilation of refractory benign esophageal strictures. Gastrointest Endosc 2009; 70: Schoepfer AM, Gonaslves N, Bussmann C, et al. Esophageal dilation in eosinophilic esophagitis: effectiveness, safety, and impact on the underlying inflammation. Am J Gastroenterol 2010; 105: Hu HT, Shin JH, Kim JH, Park JH, Sung KB, Song HY. Fluoroscopically guided balloon dilation for pharyngoesophageal stricture after radiation therapy in patients with head and neck cancer. AJR 2010; 194: Stringel G, Lawrence C, McBride W. Repair of long gap esophageal atresia without anastomosis. J Pediatr Surg 2010; 45: Kang SG, Song HY, Lim MK, Yoon HK, Goo DE, Sung KB. Esophageal rupture during balloon dilation of strictures of benign or malignant causes: prevalence and clinical importance. Radiology 1998; 209: Sharma P, Kozarek R. Role of esophageal stents in benign and malignant diseases. Am J Gastroenterol 2010; 105: Mougey A, Adler DG. Esophageal stenting for the palliation of malignant dysphagia. J Support Oncol 2008; 6: Siersema PD. Treatment options for esophageal strictures. Nat Clin Pract Gastroenterol Hepatol 2008; 5: Therasse E, Oliva V, Lafontaine E, Perreault P, Giroux MF, Soulez G. Balloon dilation and stent placement for esophageal lesions: indications, methods, and results. RadioGraphics 2003; 23: Baron TH. Expandable metal stents for the treat- AJR:198, January

6 Fan et al. ment of cancerous obstruction of the gastrointesti- tures in children. Acad Radiol 1998; 5: Brinster CJ, Singhal S, Lee L, Marshall MB, Kai- nal tract. N Engl J Med 2001; 344: Song HY, Lee DH, Seo TS, et al. Retrievable cov- ser LR, Kucharczuk JC. Evolving options in the 20. Ko GY, Song HY, Hong HJ, Sung KB, Seo TS, ered nitinol stents: experiences in 108 patients management of esophageal perforation. Ann Tho- Yoon HK. Malignant esophagogastric junction with malignant esophageal strictures. J Vasc In- rac Surg 2004; 77: obstruction: efficacy of balloon dilation combined terv Radiol 2002; 13: Freeman RK, Van Woerkom JM, Ascioti AJ. with chemotherapy and/or radiation therapy. Car- 25. Standards of Practice Committee; Egan JV, Baron Esophageal stent placement for the treatment of diovasc Intervent Radiol 2003; 26: Kim JH, Song HY, Park SW, et al. Early symptomatic strictures after gastric surgery: palliation with balloon dilation and stent placement. J Vasc Interv Radiol 2008; 19: Ko HK, Song HY, Shin JH, Lee GH, Jung HY, Park SI. Fate of migrated esophageal and gastroduodenal stents: experience in 70 patients. J Vasc Interv Radiol 2007; 18: Lisy J, Hetkova M, Snajdauf J, et al. Long-term outcomes of balloon dilation of esophageal stric- TH, Adler DG, et al. Esophageal dilation. Gastrointest Endosc 2006; 63: Kozarek RA, Patterson DJ, Ball TJ, et al. Esophageal dilation can be done safely using selective fluoroscopy and single dilating sessions. J Clin Gastroenterol 1995; 20: Fischer A, Thomusch O, Benz S, von Dobschuetz E, Baier P, Hopt UT. Nonoperative treatment of 15 benign esophageal perforations with self-expandable covered metal stents. Ann Thorac Surg 2006; 81: iatrogenic intrathoracic esophageal perforation. Ann Thorac Surg 2007; 83: Morgan RA, Ellul JP, Denton ER, Glynos M, Mason RC, Adam A. Malignant esophageal fistulas and perforations: management with plastic-covered metallic endoprostheses. Radiology 1997; 204: Shin JH, Song HY, Kim JH, et al. Comparison of temporary and permanent stent placement with concurrent radiation therapy in patients with esophageal carcinoma. J Vasc Interv Radiol 2005; 16: AJR:198, January 2012