A new method for tracheobronchial implantation of a self expandable endoprosthesis (stent)

In the treatment of malignant tracheobronchial stenosis stents are playing an increasing role. Most frequently silicone stents are used. A long-term complication of brachytherapy and laser is malacia-tracheobronchial stenosis. To improve the dyspnea and stridor, a novel technique is described by implanting a self-expanding metal-stent via the flexible fiberoptic-bronchoscope only in local anaesthesia. This procedure is fast, easy to handle and atraumatic and has lower risk of perforation, fistula, migration, bleeding and plugging by phlegm. The self-expanding metal-stent is very useful and reasonably effective for palliative treatment of tracheomalacia and malignant tracheobronchial stenosis.     

Stent implantation as a palliative therapeutic measure in stenosing tumors of central airways

PURPOSE: Stent implantation was used to treat patient with malignant tracheobronchial obstructions to determine the effectiveness in producing symptomatic palliation. METHODS: 18 patients (15 men and three women; median age 57 years) with malignant tracheobronchial stenosis were treated by application of metal stents (15 Palmaz-, 10 Gianturco-, 4 Wallstents). The indication for stent implantation was given in 13 patients by clinically significant dyspnea, besides in 5 patients by therapy resistant postobstructive pneumonia. RESULTS: In 17 patients correct positioning of the stents was achieved and the symptoms completely disappeared until tumor related death. Median survival was 137 days (min. 10 days to max. 322 days). In one patient symptoms recurred three months after stent implantation. CONCLUSION: The application of metal stents in patient with malignant tracheobronchial obstruction appears to be a useful palliation procedure. The treatment was well tolerated and very effective.     

The use of Wallstent in malignant constrictions of the gastrointestinal tract

Prosthesis implantation in malignant oesophageal stenosis, postoperative gastric outlet obstruction and jejunal stenosis is a quick and efficient method. The expansile metal stents are a new alternative to conventional plastic prosthesis. The Wallstent is made of surgical steel alloy elements braided in tubular fashion. The Wallstent is delivered in a small diameter device, but it expands to a much larger size after placement than the inner diameter of plastic stent. The small predilatations diameter makes implantation of the Wallstent less prone to cause complications or severe discomfort to the patient. The authors implanted seven Wallstents in six patients. One patient had oesophageal cancer, one ischaemic jejunal stenosis and four jejunal stenosis due to extraluminal tumour recurrences following total gastrectomy for cancer. The authors discuss in detail the usefulness of the Wallstent implantation in two cases with malignant disease of the oesophagus and jejunum. They remained symptoms free for 7 and 10 months after Wallstent implantation until death. Despite their higher initial cost, the metal stents are cost effective because of the absence of early and severe complications and the decrease in the hospitalization.     

Automatic typing of bacterial isolates

PURPOSE: To assess the use of self-expanding metallic stents in patients with inoperable malignant antrum-pylorus-duodenal obstruction. METHODS: Six patients underwent implantation of a Wallstent self-expanding metallic endoprosthesis (20 mm in five patients and 16 mm in one). In five patients a catheter (Berenstein) was introduced perorally into the stomach. A guidewire (Terumo) was introduced through the catheter and advanced through the antrum-pylorus-duodenal stenosis. The guidewire was removed and a 260-cm-long, 0.035" superstiff guide (Amplatz) was introduced. After the catheter was removed the stent assembly was introduced. In the last patient the stent was implanted through a percutaneous gastrostomy. RESULTS: Treatment of inoperable gastric outlet obstruction caused by tumor compression is difficult and unsatisfactory. Peroral implantation of self-expanding metallic stents resulted in successful palliative therapy of antrum-pylorus-duodenal stenosis in six patients in whom surgery was not possible because of advanced disease and poor general condition. On average, patients were able to eat during 41 days. One patient is tolerating oral intake at 3 months. CONCLUSION: Implantation of stents resulted in palliative relief of malignant antrum-pylorus-duodenal obstructions.     

Assessment of cold stress in outdoor work

This study was performed to determine the efficacy of balloon-expandable stents in the treatment of branch pulmonary artery-stenoses and conduit stenosis in children. A total of eight stainless steel stents were implanted in seven patients. Three patients had tetralogy of Fallot with pulmonary artery stenosis following total correction, one patient had conduit stenosis following correction of transposition of the great arteries, one patient had intra-cardiac conduit stenosis after septation for single left ventricle, and two patients had pulmonary artery stenosis after Fontan operation. Six stents were placed in the branch pulmonary arteries, one in the extracardiac conduit, and one in the intracardiac conduit. The mean age at implantation was 13 +/- 3 years and the mean weight 37 +/- 12 kg. Follow-up time ranged from 0.3-2 years. The diameter of pulmonary arteries with stenoses increased from 5.6 +/- 2.2 mm to 10.6 +/- 1.8 mm (n = 7). The systolic pressure gradient decreased from 56 +/- 26 mmHg to 22 +/- 16 mmHg (n = 5). No embolization or thrombotic event has been noted. One stent placed in the intracardiac conduit was compressed and fractured. These data indicate that balloon-expandable stents are useful in the treatment of pulmonary artery branch stenoses and extracardiac conduit stenosis in children. The use of stents for intracardiac stenosis may result in stent fracture.     

Self-expanding stents for the palliation of esophageal and gastric cardia cancer

Twenty-one endoscopic tube implantations were carried out in 24 patients with malignant stenosis of esophagus and gastric cardia using self-expanding metallic stents. The indications to endoscopic intubation were advanced stage of the tumor in 17 cases and risk factors which made resection inadvisable in 7 cases. In 3 patients it proved impossible to implant a stent endoscopically because the Authors were not able to pass the guide wire through the stenosis, while correct stent placement was achieved in 21 patients. Functional results were good in 18 patients, while 3 patients did not have any improvement of symptoms. Complications occurred in 9 patients (42.85%): 2 bleedings, 3 neoplastic obstructions, 1 food obstruction and 3 distal dislodgements of the prostheses were observed, but could readily be corrected. No death occurred. The median survival time was 151 days (range 25-545). This study suggests that endoscopic placement of metallic self-expanding stents is safe and has to be preferred to plastic stents for easier implantation and lower morbidity.     

Improved endoscopic stenting for malignant dysphagia using Tygon plastic prostheses

BACKGROUND AND STUDY AIMS: Endoscopic palliative treatment of malignant esophageal stenosis using conventional plastic stents has been reported to be associated with a considerable risk of perforation. Stenoses with a distance of less than 2cm from the upper esophageal sphincter (UES) have generally been excluded from treatment. Using self-expandable metal stents, procedure-related complications are rare. However, the rates of late complications necessitating retreatment appear to be as high as those of plastic stents. This study describes our stent placement technique and our results using a modified Tygon plastic stent. PATIENTS AND METHODS: Over a two-year period, 71 consecutive patients with incurable malignant esophageal stenosis were prospectively studied. Tygon plastic stents of diameter 9-14 mm were individually tailored according to length and location of the stenosis. Prior to stenting, stepwise bougienage was performed, if necessary over several sessions. After endoscopic placement of a guide wire, the stent was inserted over a bougie without fluoroscopic monitoring. RESULTS: A total of 71 patients (54 men and 17 women, median age 69, range 34-93), were treated with Tygon plastic stents (14 mm: 19 patients; 12 mm: 50 patients; 9 mm: 2 patients). Median length of the strictures and of the stents were 7 (range 2-18) and 10 (range 6-25) cm, respectively. Four patients had an associated esophago-respiratory fistula. After a median of 2 (range 1-5) bougienage sessions, stent insertion was technically successful in all patients. Forty-one stents were placed across the cardia, 13 were positioned 0.5-1 cm below the UES. Three patients had to undergo retreatment within 24 hours because of pain or stent migration and the stents were repositioned or exchanged. No procedure-related perforation, hemorrhage or respiratory problems were observed. During a median follow-up of 63 (range 2-388) days, 82% of the patients died. Improvement or stabilization of dysphagia allowing for oral nutrition could be achieved in 89%. Dislocation occurred in eight patients, bolus obstruction in five patients and tumor overgrowth in four patients. Three of the four fistulas could be covered by the stent. In one patient with a fistula located at the level of the UES, a stent was placed but migrated after 5 days. Overall, 27 patients (38%) required reinterventions, mainly for dysphagia or nutritional problems. CONCLUSIONS: In our experience, Tygon plastic stents with a diameter of 9-14 mm can be safely placed after stepwise, less extensive bougienage. Effective palliation is possible even for lesions located close to the UES. Perforation can be avoided. Reintervention rates seem to be comparable to those seen with self-expanding metal stents.     

Expandable metallic biliary stents

Eighteen expandable metallic biliary stents were inserted in patients with malignant (16 patients) or benign (two patients) biliary strictures. Four were the Gianturco-Rosch biliary Z-stents and the remaining 14 were the Wallstent. The stents were delivered through either the endoscopic transpapillary (10 patients), percutaneous transhepatic (five patients) or combined percutaneous-endoscopic (three patients) route. No failure in implantation was encountered. Bile drainage was successful in all patients. Stent occlusions were observed in four patients with hilar obstruction due to tumour overgrowth above the stents at 30-67 days (mean 47.75 days) after insertion. The occlusions were drained percutaneously (two patients) or endoscopically (two patients). Migration of stent did not occur. After a median follow-up period of 170.5 days (range 57-731 days), 11 patients were still alive and free of jaundice. The median patency period of the stents for common bile duct and hilar obstruction was 288.5 days (range 117-731 days) and 61.5 days (range 30-188 days), respectively. The overall median patency period was 165 days. It is concluded that expandable metallic biliary stent is a useful adjunct to the treatment of malignant biliary obstructions with a better result in distal obstruction.     

Endoscopic palliative treatment of tumors of the gastrointestinal tract

Patients with nonresectable gastrointestinal tumors have a life expectancy of a few months only. Effective palliative treatment has to ensure a good quality of life with minimal morbidity and mortality. Esophageal carcinoma: Endoscopic intubation or stent implantation guarantee a prompt improvement of dysphagia with minimal morbidity and mortality in esophageal carcinoma. Only in cervical or noncircumferential stenosis laser therapy is preferable. Obstructive jaundice: Metal stents offer the best quality of life after palliative treatment of malignant obstructive jaundice. However, in patients with bad general conditions and a short life expectancy a pigtail catheter is less expensive. Colorectal cancer: Laser therapy and cryosurgery offer uncomplicated nonsurgical therapy in rectal carcinoma. Stents in the colorectum have a high complication rate. Endoscopic palliative treatment of gastrointestinal tumors can be performed with minimal morbidity and mortality. However, it is essential that a surgeon is involved in the decisionmaking between endoscopic or operative treatment.     

Therapy of venous stenosis using wall stents

OBJECTIVE: To evaluate the patency of Wallstents implanted for the treatment of venous stenoses in patients with benign or malignant disease. PATIENTS AND METHODS: 22 Wallstents (20 central venous; two peripheral) were implanted during a period of two years in 12 patients (nine men, three women; mean age 57.8 [26-76] years) with malignant venous stenoses (n = 9) or stenosed dialysis shunts (n = 3). Stent diameter ranged from 8-16 mm, length from 32-91 mm. Introduction of the stents were by percutaneous transfemoral catheterisation, in six patients with simultaneous wire placement from a cubital to the femoral vein. The superior vena cava was the involved vessel in six patients (in two each also the subclavian or brachiocephalic veins), in three only the subclavian vein, twice only the inferior vena cava and once the cephalic vein. RESULTS: The patency of the stents was checked after 4.7 +/- 3.6 (1-14) months, in seven patients clinically, by digital subtraction phlebography in three, by computed tomography in two. In nine patients there was no evidence of obstruction to flow or flow was normal. Stent occlusion had occurred in three patients, 4, 9 and 14 months after placement. There were no complications. Five patients died after a mean period of 4.8 +/- 3.6 (1-6.5) months from the underlying disease, without symptoms of obstruction to flow. CONCLUSION: Stent placement should be considered early, as it is a well-tolerated and effective palliative procedure for central venous stenoses associated with malignant disease or stenosis of dialysis shunts.     

Palliative treatment of malignant esophageal stenosis: experience with plastic versus metal stents

BACKGROUND/AIMS: We report on the palliative treatment of 44 patients with malignant dysphagia by placement of plastic (Celestin tubes, n = 24) vs metal stents (Wall stents, Nitinol stents, Gianturco stents, n = 20). METHODOLOGY: Prior to stent insertion, esophageal stenosis was dilated stepwise to 16 mm (plastic tube) and to 10 mm (metal stent). RESULTS: Stent insertion was technically successful in all cases and led to a reduction of dysphagia. Risk of perforation was comparable in both groups (n = 1 in each group). Most of the plastic stents were placed when the tumor was localized in the proximal part of the esophagus close to the upper esophageal sphincter, when esophageal-bronchial fistula was present and in the risk of fistula development after radiation. During follow-up, tumor ingrowth (TI) and stent migration (SM) were the major complications. Whereas tumor ingrowth predominantly occurred in metal stents (TI after 6 weeks, 45% vs. SM, 10%) that required repeated argon beamer therapy, tube migration and bolus impaction (BI) often occurred in patients with plastic stents (TI, 0% vs. SM, 16%; BI, 4%). CONCLUSIONS: The findings of the study suggest that the decision whether plastic tubes or metal stents used should be taken individually considering tumor localization, axis deviation and the presence of esophago-respiratory fistulas. When stepwise dilation of malignant stenoses is performed carefully, perforation risk appears not to be different between placement of plastic prostheses and metal stents.     

Long-term results of endoscopic treatment of biliary duct obstruction due to pancreatic disease

BACKGROUND/AIMS: Endoscopic stenting has become an established method of providing palliative treatment in cases of malignant biliary obstruction, as well as in benign biliary stenosis. Several problems associated with the types of stent used have not yet been resolved, and an ideal stent has yet to be designed. Observation of the clinical course for patients with biliary obstruction of various etiologies, and evaluation of the results with various treatment methods are the aims of this study. METHODOLOGY: In 1993 and 1994, biliary obstruction was treated endoscopically in 47 patients with a malignant pancreatic tumor and in 18 patients with chronic pancreatitis. The primary intervention was assessed retrospectively on the basis of the patients' records, and information concerning the clinical course was obtained by contacting the patients or their relatives or general practitioners. RESULTS: Primary endoscopic drainage was successful in all cases. Only one of the patients with pancreatic tumors is still alive; survival after stent placement averaged 6.2 months. Metal stents remained patent significantly longer than plastic stents and percutaneous transhepatic biliary drains (PTBDs)(8.2 versus 3.5 or 1.9 months; p < 0.001). In cases of chronic pancreatitis, three of the nine patients who received only endoscopic treatment, without stenting, were able to continue without stents in the longer term, whereas seven of the nine who underwent surgery had no further problems. CONCLUSIONS: Endoscopic drainage of biliary obstruction provides excellent short-term results. In long-term treatment for purely palliative purposes, metal stents remain patent for longer than plastic stents. In chronic pancreatitis, surgical treatment clearly seems to provide better long-term results than endoscopic therapy.     

Malignant esophageal-respiratory fistula and esophageal stenosis treated with a Gianturco-Z-stent

Oesophago-respiratory fistula in most instances in a complication of advanced malignant tumours of the oesophagus or the lung. In our patient group eleven oesophago-respiratory and one gastro-respiratory fistulas were encountered. Three patients were operated upon. In one of them with achalasia, early oesophageal carcinoma was discovered in the background of the fistula. Two patients had fistulas without of oesophageal narrowing, therefore, stent implantation into the trachea and bronchus was performed. One of them was previously managed endoscopically with lyodura plug and fibrin glue, but only temporary occlusion of the fistula was obtained. In five patients, seven conventional oesophageal prosthesis (6 Cook, 1 Rüsch) were used to close the fistulas. In one of these patients, three oesophago-respiratory fistulas developed one after the other at the level of the prosthesis funnel. They were closed with three prostheses connected with short silicone tubes. In the last two patients, Gianturco-Z stent was employed. Its advantages over the plastic prostheses include small basic and lager final luminal diameter, lesser predilatation, easier implantation, lower complication and mortality rate. The silicone coated and double funnel stent with expansile force is effective in fistulas closure. On implantation, stent shortening in minimal, allowing precise placement of the stent even in proximal malignant oesophageal stenosis with oesophago-bronchial fistula. The high price of the stent is compensated for by the lower complication rate, shorter hospitalization and subsequent reduction is hospital expenses. Therefore these metal stents should be financed by the National Health Service, at least in specialized centers for managing patients with dysphagia.     

Palliative treatment of malignant esophageal obstruction with a new endoscopically administered self-expanding nitinol stent: case report

The endoscopic methods of palliative treatment in malignant esophageal stenoses caused by neoplasm which have been performed so far unfortunately do not provide permanently satisfying results. The implantation of self-expanding stents with the purpose of removing malignant esophageal obstructions has recently become the most acceptable method of treatment. By using that method it is possible to reduce or even completely remove difficulties in swallowing. In that way a significant improvement in life quality of patients with inoperable esophageal cancer is possible. The various types of metal endoprostheses used for the palliative treatment of esophageal malignant stenoses are described in this paper. Here is also presented a case of nitinol stent implantation in a 50 year old woman suffering from esophageal cancer. This type of therapeutic treatment has been applied in Croatia for first time.     

Nitinol alloy endotracheal stent used in treatment of tracheal stenosis: experimental and clinical applications

A new method used in treatment of tracheal stenosis by means of nitinol alloy intraluminal tracheal stent (Ni-Ti ITS) is introduced. Altogether 7 stents were implanted into tracheas of 7 mongrels each with a model of tracheal stenosis. The observation periods ranged from 2 to 6 months. The experimental results showed: The Ni-Ti ITSs could maintain long term patency without severe infection or obstruction by granulations or secretion. No displacement was found. There were no signs of either generalized or localized corrosion on the surface of stents. The shape memory character remained unchanged. On the basis of animal experimental study, the stents were successfully used in treatment of 2 patients with tracheal stenosis. One was caused by advanced tracheal tumor, the other was due to recurrent anastomotic stricture.     

Magnetic resonance imaging and audiologic assessment of middle ear effusions in patients with nasopharyngeal carcinoma before radiation therapy

Recently, stent implantation has become the treatment of choice for patients with tracheobronchial stenosis due to malignant tumours, tuberculosis and recurrent stenosis following lung transplant. However, reports on this procedure in infants with congenital bronchial stenosis are extremely rare. We report successful stent implantation in an infant with congenital left bronchial stenosis followed by rapid improvement in his respiratory condition. CONCLUSION: The use of a stent in infants is still controversial because size mismatch will take place with growth. However, we believe that implantation of a metallic stent can be the preferred treatment of congenital bronchial stenosis even in small infants.     

Interventional catheter therapy in childhood

The paediatric therapeutic heart catheterization becomes more and more important in the treatment of congenital heart disease. Depending on the situation, interventional therapy can become an alternative or a replacement or supplement to surgical intervention. The methods of interventional therapy include the balloon valvuloplasty of stenotic valves or vessels, the implantation of stents and the occlusion of defects as well as of unwanted vascular structures with coil embolisation or umbrella devices. The balloon valvuloplasty of pulmonary valve stenosis or the embolisation of small vessels have become the treatment of choice. Valvuloplasty of aortic stenosis, angioplasty of residual coarctation, balloon dilatation of peripheral pulmonic stenosis and occlusion of a patent ductus arteriosus with a Rashkind PDA-occluder are now a valuable alternative to surgical procedure although studies of long-term results are not yet available. Occlusions of atrial or ventricular septal defects as well as the implantation of stents are still investigational tools, but give enormous hope for the future.     

Nitinol alloy endotracheal stent for treatment of tracheal stenosis

OBJECTIVE: To treat inoperable tracheal stenosis by using nitinol endotracheal stent and to solve some problems facing endotracheal stenting with other kinds of stents. METHODS: The stent was made of nitinol wire. It can be deformed to smaller size in iced water. With a self-made introducer, the stent was placed in the location of stenosis. After hot water was injected into the introducer, the stent resumed its original form and anchored there itself. RESULTS: Altogether, 5 patients with severe tracheal stenosis received this treatment. Dyspnea was relieved immediately after implantation of stents in all patients. Long-term follow-up also showed satisfactory results. CONCLUSION: Nitinol stent has some remarkable advantages as compared with other tracheal stents. It can be used as a new endoprosthesis in treating narrowed trachea.     

Myocardial perfusion scintigraphy to evaluate patients after coronary stent implantation

Coronary stent implantation is an increasingly accepted revascularization method. The 20%-30% restenosis rate during the first 6 mo requires a close follow-up of the patients. Since there is very little data available defining the role of perfusion scintigraphy in the management of this population, the aim of this study was to assess the diagnostic performance of stress myocardial perfusion imaging for detecting restenosis in patients after coronary stent implantation. METHODS: In 82 patients, 93 rest or stress SPECT studies were performed using 201Tl and 99mTc-hexakis-2-methoxyisobutyl isonitrile to evaluate 99 vascular territories with implanted coronary stents. The average interval between the stent implantation and the scintigraphic study was 210.5 +/- 129.6 days. The scintiscans were visually evaluated. A stress-induced perfusion defect with reversibility at rest was used as the criterion for stent restenosis. RESULTS: Coronary angiography revealed a stenosis of > 50% diameter in the region of the stent in 19 arteries, while in 80 arteries there was no evidence of restenosis angiographically. With perfusion scintigraphy, 15/19 vascular territories with restenosed stents showed stress-induced perfusion abnormalities (sensitivity = 79%), while 62/80 territories without restenosis did not (specificity = 78%). In territories without a myocardial infarction (n = 48), sensitivity and specificity values were 8/8 (100%) and 36/44 (82%), and in territories with a myocardial infarction (n = 47) 7/11 (64%) and 26/36 (72%), respectively. Side branch stenosis was fairly frequent in patients without stent restenosis but with a reversible perfusion pattern on their scintiscan (8/18); however, these stenoses were induced infrequently by the stents (3 cases). CONCLUSION: Using the criterion of defect reversibility, stress perfusion SPECT can accurately detect restenoses of coronary artery stents. This method is most accurate for evaluating patients without a previous myocardial infarction in the stented vascular territory.     

Palliative treatment of malignant esophagorespiratory fistulas with Gianturco-Z stents. A prospective clinical trial and review of the literature on covered metal stents

OBJECTIVE: Esophagorespiratory fistulas, especially in the upper third of the esophagus, are a complication of malignant esophageal tumors, which are difficult to manage. The efficacy of polyurethane-covered, self-expanding metal stents for palliation of malignant esophagorespiratory fistulas was investigated prospectively. METHODS: Eleven patients with malignant esophagorespiratory fistulas resp. perforations were treated with Gianturco-Z stents. In five patients the lesion was located in the proximal part of the esophagus. Because of the fistula all patients suffered from dysphagia even for liquids. RESULTS: No technical problems during the implantation procedure of the stents occurred. In the control radiography with water-soluble contrast media, the fistulas were completely sealed in 10 of 11 patients. Therefore the dysphagia score improved from 3.0 to 0.6. Nearly all Gianturco-Z stents (10/11) showed a sufficient expansion within 24 h after placement. Severe early or late complications were not encountered, with the exception of tumor overgrowth in one patient about 9 months after stent placement. In five patients, short term (3-6 days) retrosternal pain was observed, and one patient complained of slight foreign body sensation. By August 1997 all 11 patients had died of advanced disease, with a median survival time of 121 days (range, 22-300 days). CONCLUSIONS: Gianturco-Z stents are highly effective for palliative treatment of esophagorespiratory fistula resp. perforations and have a low complication rate. Due to the fact that this stent shows no retraction during the release, a precise positioning is possible, especially in the case of tumors and fistulas in the upper third of the esophagus. It seems that use of the Gianturco-Z stent can be considered a good therapeutic method for palliative endoscopic treatment of this high risk patient group.