Improving culprit artery identification with intraprocedural cone-beam CT aortography and its clinical impact in bronchial artery embolization.

OBJECTIVE: To evaluate the impact of intraprocedural cone-beam CT (CBCT) aortography on culprit artery identification and clinical outcomes in patients undergoing bronchial artery embolization (BAE). MATERIALS AND METHODS: Two hundred eighty-two patients with 317 BAE procedures were retrospectively reviewed. Patients who underwent preprocedural chest CT angiography (CTA) without intraprocedural CBCT aortography were categorized as Group A (n = 177). Patients who underwent both preprocedural chest CTA and intraprocedural CBCT aortography were categorized as Group B (n = 105). Whether CBCT can provide improved culprit artery identification and whether this improvement has a clinical impact were evaluated by comparing the two Groups. RESULTS: In Group B, CBCT aortography detected more culprit non-bronchial systemic arteries originating from the subclavian arteries compared to chest CTA (16 vs 3, p = 0.026), and the average number of embolized vessels was significantly higher than in Group A (2.47 ± 1.61 vs 2.03 ± 1.17, p = 0.016), while the procedure time was shorter (37.4 ± 22.0 vs 43.6 ± 22.7 min, p = 0.024). The recurrent hemoptysis rate was lower in Group B (17.5% vs 8.7%, p = 0.041), and the proportion of patients requiring subsequent procedures was significantly lower (12.4% vs 4.8%, p = 0.035). The changes in estimated glomerular filtration rate before and 3 days after the procedure (0.1 ± 12.8 vs 0.3 ± 11.0 mL/min/1.73 m2, p = 0.909) and total dose area product (DAP, 6119.5 ± 5725.7 vs 6906.2 ± 5978.6 uGym2, p = 0.279) were not significantly different between the two groups. CONCLUSION: BAE with intraprocedural CBCT aortography enabled the embolization of more culprit arteries, leading to lower recurrent hemoptysis rates without increasing the risk of renal deterioration and radiation hazards when compared to procedures without it. KEY POINTS: Question Does intraprocedural CBCT aortography improve culprit artery detection and clinical outcomes in BAE for hemoptysis? Findings CBCT aortography significantly improved the detection of additional culprit arteries, especially from non-bronchial systemic arteries, increasing the number of vessels treated during BAE. Clinical relevance Using CBCT aortography during BAE results in better long-term outcomes by reducing recurrent hemoptysis and the need for additional procedures, without increasing the risk of renal impairment.

The role of Eustachian tubography and Valsalva CT in Eustachian tube balloon dilation.

BACKGROUND: Not many imaging techniques have been reported in Eustachian tube imaging. PURPOSE: To investigate the role of selective Eustachian tubography (SET) and Valsalva computed tomography (CT) in patients who underwent Eustachian tube balloon dilation (ETBD). MATERIAL AND METHODS: Eligible patients were aged 18 years and older with chronic Eustachian tube dysfunction who had failed medical treatment. On the day of the procedure, Valsalva CT and SET were performed. Participants underwent fluoroscopic ETBD with a 6×20-mm balloon catheter. Clinical examinations to check for the ability to perform the Valsalva maneuver and ETDQ-7 score change were conducted at one week and then at one, two, and six months. Follow-up Valsalva CT was performed in the one-month follow-up. RESULTS: A total of 30 ears in 23 patients (16 right ears, 14 left ears; 10 women, 13 men) underwent ETBD from August 2018 to November 2019. Positive CT patency was higher in follow-up Valsalva CT than baseline Valsalva CT (40% and 23.3%, respectively) (P = 0.006). In SET, positive patency was observed in 13 of 25 ears. Response to balloon dilation was observed in 18 of 25 patients. Clinical success was achieved in 16 of 27 ears. Response to balloon dilation was the only significant predictor of clinical success (P = 0.012). CONCLUSION: SET depicted the lumen of the Eustachian tube; thereby, it could be a potentially valuable tool in ETBD. Valsalva CT provides additional information about the cartilaginous portion of the Eustachian tube.

Factors Affecting Recurrent Deep Vein Thrombosis after Pharmacomechanical Thrombolysis and Left Iliac Vein Stent Placement in Patients with Iliac Vein Compression Syndrome.

PURPOSE: This study evaluated the factors affecting contralateral and ipsilateral recurrent deep vein thrombosis (DVT) after iliac vein stent placement in patients with iliac vein compression syndrome (IVCS). MATERIALS AND METHODS: Data from 130 patients (95 female patients) who underwent catheter-directed thrombolysis and stent placement for IVCS with left lower leg thrombosis at a single institution were retrospectively analyzed. Mean patient age was 69.0 ± 14.0 years old. Median follow-up was 14 months (range, 3-164 months). Anticoagulation therapy was prescribed for 6 months, followed by lifelong antiplatelet therapy. Multivariate logistic regression analysis was performed to evaluate the factors affecting the development of contralateral and ipsilateral recurrent DVT. RESULTS: Seven patients (5.4%) developed contralateral DVT (median, 26 months; range, 2-61 months), and 11 patients (8.5%) developed ipsilateral DVT (median, 1 month; range, 0-53 months). Stent location (odds ratio [OR], 11.564; 95% confidence interval [CI], 1.159-115.417) and in-stent thrombosis during follow-up (OR, 15.142; 95% CI, 1.406-163.119) were predictors of recurrent contralateral DVT. Thrombophilia (OR, 47.560; 95% CI, 2.369-954.711), remaining inferior vena cava filter (OR, 30.552; 95% CI, 3.495-267.122), and in-stent thrombosis during follow-up (OR, 82.057; 95% CI, 2.915-2309.848) were predictors of ipsilateral DVT. CONCLUSIONS: Contralateral DVT occurs late and is associated with extension of the iliac vein stent to the inferior vena cava and in-stent thrombosis. Ipsilateral DVT occurs relatively early and is associated with thrombophilia, remaining inferior vena cava filter, and in-stent thrombosis.

Single-Center Retrospective Study of Preoperative Prostatic Artery Embolization with the Use of Gelatin Sponge: Initial Experience and Influence for Blood Loss in Prostate Surgery.

PURPOSE: To investigate the safety and effectiveness of preoperative prostatic artery embolization (PAE) in relation to decrease in hemoglobin level, requirement for blood transfusion, length of hospitalization, and procedure-related complications. MATERIALS AND METHODS: Ten consecutive patients who underwent surgery after preoperative PAE were identified from May 2017 to October 2018 (embolization group: holmium-laser enucleation of the prostate [HoLEP] in 6 patients and robotic simple prostatectomy in 4 patients, mean age 72.9 ± 8.7 years, mean prostatic volume 106.5 ± 22.0 mL). For comparison, consecutive patients with a large prostatic volume (≥70 mL) who underwent surgery without preoperative PAE during the same period were enrolled (nonembolization group: HoLEP in 9 patients and robotic simple prostatectomy in 1 patients, mean age 71.2 ± 5.7 years, mean prostatic volume 87.8 ± 26.7 mL). RESULTS: PAE was technically successful in 90% of patients (9/10). The median interval between PAE and surgery was 2 days. The mean hemoglobin reduction was lower (1.40 ± 0.92 g/dL vs 3.07 ± 1.50 g/dL; P = .008) and the median length of hospitalization was shorter (8.5 days vs 11 days; P = .039) in the embolization group than the nonembolization group. The operating time (mean for HoLEP 146 ± 38 min vs 179 ± 59 min [P = .248], mean for robotic simple prostatectomy 223 ± 32 min vs 354 min) and number of blood transfusion (1 patient vs 2 patients; P = .392) were not significantly different between the 2 groups. None of the patients developed any complications except bleeding requiring transfusion. CONCLUSIONS: Preoperative PAE is safe and may reduce blood loss during prostate surgery.

Fluoroscopic Balloon Dilation Using a Flexible Guide Wire to Treat Obstructive Eustachian Tube Dysfunction.

PURPOSE: To prospectively evaluate the midterm outcomes of fluoroscopic eustachian tube (E-tube) balloon dilation by using a flexible guide wire in patients with obstructive E-tube dysfunction. MATERIALS AND METHODS: From October 2016 to September 2017, adult outpatients with persistent otitis media who were unable to perform the Valsalva maneuver were prospectively enrolled. The analysis included 32 E-tubes from 31 patients (18 women, 13 men; mean age, 47 years old, range 25-72 years). Participants underwent fluoroscopic E-tube balloon dilation with a 0.035-inch flexible guide wire and a 6- × 20-mm balloon catheter. Clinical examinations to check for the ability to perform the Valsalva maneuver and otomicroscopy were conducted at 1 week and then at 1, 3, 12, and 18 months after the procedure. RESULTS: Balloon dilation was technically successful in all E-tubes. The mean time required for the procedure was 6.9 minutes (range, 5.8-10.3 minutes). The Valsalva maneuver was successful in opening 25 of 32 E-tubes (78.1%) at 3 months after balloon dilation. During the median follow-up of 15.9 months, failure of the Valsalva maneuver occurred in 4 of 25 improved E-tubes (16%), yielding a 2-year patency rate of 84%. CONCLUSIONS: The fluoroscopic balloon dilation results were encouraging, and using a flexible guide wire for E-tube balloon dilation did not cause a false passage.

Developmental endothelial locus-1 prevents development of peritoneal adhesions in mice.

Postoperative peritoneal adhesions, fibrous bands formed in the peritoneal cavity following surgery, represent a common, challenging and costly problem faced by surgeons and patients, for which effective therapeutic options are lacking. Since aberrant inflammation is one of the key mechanisms underlying peritoneal adhesion formation, here we set out to study the role of developmental endothelial locus-1 (Del-1), which has been recently identified as an endogenous inhibitor of inflammation, in the formation of postoperative peritoneal adhesions using a mouse model of peritoneal adhesions induced by ischemic buttons. Del-1-deficient mice had a higher incidence of adhesions, and their adhesions had higher quality and tenacity scores. Del-1 deficiency also led to enhanced inflammation mediators and collagen production. Finally, Del-1 supplementation decreased the incidence and severity of postoperative peritoneal adhesions. Taken together, these results indicate a protective role for Del-1 in postoperative peritoneal adhesion formation.

Sirolimus-eluting Biodegradable Poly-l-Lactic Acid Stent to Suppress Granulation Tissue Formation in the Rat Urethra.

Purpose To investigate the use of sirolimus-eluting biodegradable stents (SEBSs) to suppress granulation tissue formation after stent placement in a rat urethral model. Materials and Methods All experiments were approved by the animal research committee. A total of 36 male Sprague-Dawley rats were randomized into three equal groups after biodegradable stent placement. Group A received control biodegradable stents. Groups B and C received stents coated with 90 µg/cm2 and 450 µg/cm2 sirolimus, respectively. Six rats in each group were sacrificed after 4 weeks; the remaining rats were sacrificed after 12 weeks. The therapeutic effectiveness of SEBSs was assessed by comparing the results of retrograde urethrography and histologic examination. Analysis of variance with post hoc comparisons was used to evaluate statistical differences. Results SEBS placement was technically successful in all rats. Urethrographic and histologic examinations revealed significantly less granulation tissue formation at both time points in the rats receiving SEBSs (groups B and C) compared with those that received control stents (group A) (P < .05 for all). There were no significant differences in urethrographic and histologic findings between groups B and C (P > .05 for all). However, the mean number of epithelial layers in group B was higher than that in group C at 4 weeks after stent placement (P < .001). Apoptosis increased in group C compared with groups A and B (P < .05 for all). Conclusion The use of SEBSs suppressed granulation tissue formation secondary to stent placement in a rat urethral model; local therapy with SEBSs may be used to decrease stent-related granulation tissue formation. © RSNA, 2017.

Fluoroscopy-guided balloon dilation in patients with Eustachian tube dysfunction.

OBJECTIVES: To prospectively evaluate the technical feasibility and safety of fluoroscopy-guided balloon dilation in patients with Eustachian tube (ET) dysfunction. METHODS: Patients who could not do a Valsalva manoeuvre for more than 6 months and diagnosed with chronic otitis media or ET dysfunction were prospectively enrolled. A 0.035-in. guide wire and 6-mm long balloon catheter with a diameter of 2 mm were used to dilate the cartilaginous portion of the ET under fluoroscopic guidance. The balloon was inflated by manual injection twice for 1 min each time. Clinical outcomes were assessed by the patient's ability to perform a Valsalva manoeuvre, and symptoms were assessed using the 7-item Eustachian Tube Dysfunction Questionnaire (ETDQ-7) score. RESULTS: Balloon dilation was attempted in a total of ten adult patients from October 2016 to March 2017. Technical success was achieved in all procedures (10/10). Ninety percent (9/10) of the balloons were fully dilated without waist deformity. There were no major complications. All patients were able to perform a Valsalva manoeuvre at the time of their last visit and/or improvement of at least one ETDQ-7 score. CONCLUSION: Fluoroscopy-guided balloon dilation seems to be technically feasible and safe in the treatment of ET dysfunction. KEY POINTS: • Fluoroscopy-guided balloon dilation without general anaesthesia was well-tolerated in all patients. • Location of the balloon catheter can be monitored during the procedure. • Inflation state of the balloon catheter can be monitored during the procedure. • Using guide-wire during the procedure would prevent false passage creation. • All patients had clinical improvement within 3 months after balloon dilation.

Fluoroscopic subtraction Eustachian tubography: initial feasibility test in a cadaver model.

OBJECTIVES: To evaluate the technical feasibility of direct Eustachian tube catheterisation and subtraction Eustachian tubography in a cadaver model. METHODS: A total of 12 separate sessions were performed on both sides of the Eustachian tube (ET) in six human cadavers. Cadavers were positioned for the submentovertical view on a fluoroscopy table. Endoscopy-guided ET selection was used in the first three cadavers, whereas fluoroscopy-guided ET selection was used in the remaining three. Eustachian tubography was performed by injecting 2 ml of contrast media through a 5-Fr catheter. We recorded the success of ET selection, number of attempts, procedure time, and tubography quality using native and subtraction images (range, 0-3). RESULTS: Both endoscopy- and fluoroscopy-guided selections were successfully performed in five of six sessions (83.3%). There were no statistically significant differences between the endoscopy- and fluoroscopy-guided procedures in terms of the number of attempts, procedure time, rate of immediate contrast leak to the middle ear cavity, and quality of tubography (p > 0.05). An excellent quality of tubography was obtained in 83.3% (10 of 12 sessions) of subtraction images and in 33.3% (4 of 12 sessions) of native images. The tubography quality score was significantly higher for the subtraction images than for the native images (p = 0.04). CONCLUSION: Subtraction Eustachian tubography using direct catheterisation seems to be technically feasible. The entire ET can be well visualised; thus, this technique can be used as a simple tool for assessment of ET function and anatomy. KEY POINTS: • Direct catheterisation of the Eustachian tube is technically feasible. • The entire Eustachian tube could be well visualised by direct Eustachian tubography. • Subtraction Eustachian tubography images have better image quality than native images. • Subtraction Eustachian tubography can provide objective assessment of ET function and anatomy.

Self-Expandable Metal Stent Use to Palliate Malignant Esophagorespiratory Fistulas in 88 Patients.

PURPOSE: To identify predictors associated with clinical outcomes (initial clinical failure, stent patency, and survival) after self-expandable metal stent (SEMS) placement for malignant esophagorespiratory fistulas (ERFs). MATERIALS AND METHODS: Using logistic and Cox regression analyses, this study reviewed 88 patients (mean age 59.4 y ± 8.4; 84 men [95.5%] and 4 women [4.5%]) who underwent fluoroscopic SEMS placement for palliating malignant ERF from January 2000 to December 2016. RESULTS: Technical success was achieved in all patients. Initial clinical success was achieved in 78.4% (69/88; 95% confidence interval [CI], 68.7%-85.7%). Among the 69 patients in whom initial clinical success was achieved, aspiration symptoms recurred in 37.7% (26/69; 95% CI, 27.2%-49.5%). Overall major complication rate was 25.0% (22/88; 95% CI, 17.1%-35.0%). Cumulative stent patency and cumulative survival rates at 1, 3, 6, and 12 months were 72.8%, 38.9%, 32.4%, and 21.6% and 81.4%, 51.9%, 30.5%, and 13.3%, respectively. Stricture of the upper esophagus was an independent predictor of initial clinical failure (odds ratio, 3.760; 95% CI, 1.207-11.811) and shorter stent patency (hazard ratio [HR], 2.036; 95% CI, 1.170-3.544). Initial clinical failure was an independent predictor of shorter survival (HR, 2.902; 95% CI, 1.587-5.305). CONCLUSIONS: SEMS placement offers sufficient short-term relief despite considerable major complications. Stricture of the upper esophagus is an independent predictor of initial clinical failure and shorter stent patency. Initial clinical failure is an independent predictor of shorter survival.

Transnasal Placement of a Balloon-Expandable Metallic Stent: Human Cadaver Study of the Eustachian Tube.

PURPOSE: To investigate the technical feasibility of stent placement in the cartilaginous portion of the Eustachian tube (ET). MATERIALS AND METHODS: Twelve ETs of 6 cadavers were used. Two different-sized stents were placed on either the right (2.5 mm in diameter) or left (3.5 mm in diameter) side of the ET. The procedural feasibility was assessed by subtraction Eustachian tubography, computed tomography before and after the procedure, and fluoroscopic and endoscopic images. The stent location, inner luminal diameter of the stented ET, radiation dose, procedural time, and fluoroscopy time were analyzed. RESULTS: Stent placement was successful in 11 of 12 cadaveric specimens without procedure-related complications. In the 1 specimen, the balloon catheter with crimped stent was passed into the bony canal of the ET without any resistance. The distal end of the stent was located in the middle ear cavity. Stents were located within the cartilaginous portion of the ET (n = 1), the proximal tip bridging the nasopharyngeal orifice of the ET (n = 5), or the proximal end of the stent protruded from the tubal orifice (n = 5). The mean luminal diameter in the outer segment was significantly smaller than in the middle (P < .001) and inner (P < .001) segments. The mean procedure time was 128 ± 37 seconds. The mean radiation dose and fluoroscopy time of each cadaver were 3235.4 ± 864.8 cGy/cm2 and 139 ± 49 seconds, respectively. CONCLUSIONS: Stent placement of the ET under endoscopic and fluoroscopic guidance is technically feasible in a human cadaver model.

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.

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 balloon diameter measurement at different pressures during Eustachian balloon dilation.

OBJECTIVES: To measure the diameter of inflated balloons at different pressures during Eustachian tube (ET) balloon dilation under fluoroscopic guidance. DESIGN: Prospective cohort study. SETTING: Tertiary academic referral centre. PARTICIPANTS: Eighteen patients who underwent ET balloon dilation with use of a balloon catheter, 20 mm long and 6 mm in diameter, under combined endoscopic and fluoroscopic guidance. MAIN OUTCOME MEASURES: Degrees of inflation at three different portions (proximal, middle and distal) of the balloon at controlled pressures (3, 5, 8 and 10 atmospheres [atm]) and at the maximum pressure manually applied. RESULTS: The mean proximal, middle and distal diameters of the inflated balloons were 5.3 ± 0.4 mm, 5.3 ± 0.4 mm and 4.9 ± 0.5 mm at 10 atm. The distal diameters were significantly smaller than middle and proximal diameters at all the pressures (P < 0.01). When compared to the distal diameter (100%, 4.9 ± 0.5 mm) at 10 atm, the distal diameters were 73% (3.6 ± 0.6 mm) at 3 atm, 88% (4.3 ± 0.5 mm) at 5 atm and 96% (4.7 ± 0.4 mm) at 8 atm. The distal diameter (4.1 ± 0.3 mm) at the maximum pressure manually applied was in between those at 3 and 5 atm. CONCLUSIONS: The distal diameter of the balloon increased significantly as a function of the pressure and most (88%) inflation occurred at a low pressure of 5 atm, which was sufficient to inflate the distal diameter of the balloon more than 3 mm. The manual pressurisation could inflate a balloon by as much as could be expected, at between 3 and 5 atm.

EW-7197, an activin-like kinase 5 inhibitor, suppresses granulation tissue after stent placement in rat esophagus.

BACKGROUND AND AIMS: Self-expanding metallic stent (SEMS) placement is a well-established method for treating malignant esophageal strictures; however, this procedure has not gained widespread acceptance for treating benign esophageal strictures because of granulation tissue formation. The aim of the present study was to investigate whether EW-7197, a novel per-oral transforming growth factor-ß type I receptor kinase inhibitor, suppressed granulation tissue formation after SEMS placement in the rat esophagus. METHODS: Sixty rats underwent SEMS placement and were randomly divided into 4 groups. Group A (n = 20) received vehicle-treated control for 4 weeks. Group B (n = 20) received 20 mg/kg/day EW-7197 for 4 weeks. Group C (n = 10) received 20 mg/kg/day EW-7197 for 4 weeks followed by vehicle-treated control for 4 weeks. Group D (n = 10) received 20 mg/kg/day EW-7197 for 8 weeks. RESULTS: SEMS placement was technically successful in all rats. Eleven rats, however, were excluded because of stent migration (n = 9) and procedure-related death (n = 2). The luminal diameter in group A was significantly smaller than those in groups B, C, and D (all P < .001). The percentage of granulation tissue area, number of epithelial layers, thickness of submucosal fibrosis, percentage of connective tissue area, and degree of collagen deposition were significantly higher in group A than in groups B, C, and D (all P < .001); however, there were no significant differences among groups B, C, and D. EW-7197 decreased the expression levels of phospho-Smad 3, N-cadherin, fibronectin, α-smooth muscle actin, and transforming growth factor-ß1 and increased the expression level of E-cadherin (all P < .01). CONCLUSIONS: EW-7197 suppressed granulation tissue formation after SEMS placement in the rat esophagus.

Recurrent Benign Urethral Strictures Treated with Covered Retrievable Self-Expandable Metallic Stents: Long-Term Outcomes over an 18-Year Period.

PURPOSE: To assess the long-term outcomes of covered retrievable self-expandable metallic stent (REMS) placement for recurrent benign urethral stricture and to compare the outcomes associated with 3 types of covered REMSs. MATERIALS AND METHODS: A retrospective study was performed in 54 male patients in whom 114 REMSs were placed between November 1998 and December 2016. These included 26 polyurethane-covered REMSs in 13 patients (group A), 47 internally polytetrafluoroethylene (PTFE)-covered REMSs in 21 patients (group B), and 41 externally PTFE-covered REMSs in 20 patients (group C). The outcomes were analyzed and compared between the groups. RESULTS: Overall clinical success was achieved in 14 of the 54 patients (24%) at 5-year follow-up (group A, 12%; group B, 19%; group C, 40%). The overall complication rate was 60.5%, and the complication rate was significantly higher in group B than in groups A or C (group A vs B, P = .018; group B vs C, P = .002). The median stent indwelling time and maintained patency period were 3.1 months and 108 months, respectively. In multivariate analysis, stent indwelling time was the only significant factor associated with maintained patency. CONCLUSIONS: The long-term outcome of covered REMSs has not achieved the desired success rate for the standard treatment of recurrent urethral stricture. However, externally PTFE-covered REMSs showed a better long-term outcome than the other studied types.

Fluoroscopic Balloon Dilation for Treating Postoperative Nonanastomotic Strictures in the Proximal Small Bowel: A 15-Year Single-Institution Experience.

PURPOSE: To evaluate safety and effectiveness of fluoroscopic balloon dilation (FBD) for treating postoperative nonanastomotic strictures in proximal small bowel. MATERIALS AND METHODS: Data of 44 patients (26 men and 18 women; mean age, 53.7 y ± 13.0) treated with FBD for postoperative nonanastomotic strictures in the proximal small bowel between January 2000 and February 2016 were retrospectively reviewed. Site of stricture was located in the first portion of duodenum in 8 (18.2%) patients, second portion of duodenum in 8 (18.2%) patients, third portion of duodenum in 1 (2.3%) patient, fourth portion of duodenum in 1 (2.3%) patient, and proximal jejunum in 26 (59.1%) patients. Mean distance between the most anal-side lesion and the oral cavity was 63.9 cm ± 15.0. RESULTS: Technical success was achieved in 39 (88.6%) patients. Mean stricture length was 3.0 cm ± 1.8. Technical failure because of inability to negotiate the guide wire through the stricture occurred in 5 (13.6%) patients. Complete resolution of obstructive symptoms and resumption of oral intake of soft or solid food within 3 days occurred in 34 patients after 1 (n = 32) or 2 (n = 2) FBD sessions, rendering a clinical success rate of 87.2%. There were no major complications directly related to FBD. Median follow-up period was 1,406 days (interquartile range, 594-2,236 d). Nine (26.5%) patients had recurrence within a median 47 days (interquartile range, 20-212 d). CONCLUSIONS: FBD may be safe and effective for treating postoperative nonanastomotic strictures in the proximal small bowel.

Significance of Stent Abutment in Gastroduodenal Stent Placement for Gastric Outlet Obstructions.

PURPOSE: To evaluate the frequency, severity, and clinical significance of stent abutment (SA) after gastroduodenal stent placement in patients with gastric outlet obstruction caused by unresectable gastric cancer. MATERIALS AND METHODS: A retrospective study was conducted in a single tertiary referral university hospital to identify the incidence and clinical significance of SA in 318 patients who underwent self-expandable metallic stent placement. SA was defined as abutment of the distal end of the stent to the duodenal wall and/or superior duodenal flexure. The outcomes included technical and clinical success, complications, repeat intervention, stent patency, and survival. RESULTS: A total of 318 patients, 107 with SA (33.6%) and 211 without, were included. SA occurred partially (n = 64; 59.8%) and completely (n = 43; 40.2%). The technical and clinical outcomes and survival were similar in the groups with and without SA. Food impaction and resultant repeat intervention rates were higher in the SA group than in the non-SA group (P < .001 and P < .001, respectively), and were associated with complete SA (P = .007). Stent patency rate was lower in the SA group than in the non-SA group (P = .003). CONCLUSIONS: SA was associated with increased food impaction, resulting in a greater incidence of stent malfunction and shorter stent patency compared with a lack of SA. The concept of SA may be useful for the improvement of stent patency and avoidance of food impaction.

Self-Expandable Metallic Stent Placement for the Palliation of Esophageal Cancer.

Esophageal stents have been used to palliate patients with dysphagia caused by esophageal cancer. Early rigid plastic prostheses have been associated with a high risk of complications. However, with the development of self-expanding stents, it has developed into a widely accepted method for treating malignant esophageal strictures and esophagorespiratory fistulas (ERFs). The present review covers various aspects of self-expanding metallic stent placement for palliating esophageal cancer, including its types, placement procedures, indications, contraindications, complications, and some of innovations that will become available in the future.

Development of a Rabbit Iliac Arterial Stenosis Model Using a Controlled Cholesterol Diet and Pullover Balloon Injury.

Purpose: This study aimed to develop a rabbit iliac stenosis model and evaluate the effects of different mechanical injury techniques on the degree of arterial stenosis. Materials and Methods: Eighteen rabbits were divided into three groups: cholesterol-fed with pullover balloon injury (group A; n = 6), cholesterol-fed with localized balloon dilatation (group B; n = 6), and chow-diet with pullover balloon injury (group C; n = 6). After baseline angiography, the left iliac arteries of all rabbits were injured with a 3 × 10 mm noncompliant balloon using either a wide pullover technique (groups A and C) or a localized balloon dilatation technique (group B). A nine-week follow-up angiography was performed, and the angiographic late lumen loss and percentage of stenosis were compared. Results: Group A exhibited the most severe late lumen loss (A vs. B, 0.67 ± 0.13 vs. 0.04 ± 0.13 mm, p < 0.0001; A vs. C, 0.67 ± 0.13 vs. 0.26 ± 0.29 mm, p < 0.05; stenosis percentage 32.02% ± 6.54%). In contrast, group B showed a minimal percentage of stenosis (1.75% ± 6.55%). Conclusion: Pullover-balloon injury can lead to significant iliac artery stenosis in rabbits with controlled hypercholesterolemia. This model may be useful for elucidating the pathogenesis of atherosclerosis and for evaluating the efficacy of novel therapeutic interventions.