Prosthetic replacement of the ureters

STUDY AIM: The aim of this study is to demonstrate the reliability of silicone prosthesis for the replacement of ureters. This prosthesis derives from the biliary prosthesis developed after a personal experimental study continued by Triboulet. PATIENTS AND METHODS: In 38 patients suffering from a malignant disease, a right silicone prosthesis was used for the replacement of an ureter during a 20-year period. There were 30 female and eight male patients. The mean age was 71 (range: 51-88 years). Forty one prostheses were used; one patient underwent two successive operations on the same side with a change of prosthesis, and two patients required a bilateral prosthesis. There were 12 gynaecological carcinomas (three with ureteral fistula), three prostatic carcinomas, 16 cancers of the rectum and recto-sigmoid junction, four cancers of the right colon with retroperitoneal carcinomatosis, and three ureteral fistulas after extended colonic resection. RESULTS: Early complications were limited to ureteral fistulas (n = 6, 16%) in patients who had already a preoperative fistula (n = 3) and in patients with peritoneal metastases on the superior wall of the bladder. The secondary destruction of the kidney (four secondary nephrectomies) occurred when the function of the kidney was already impaired at the time of the procedure. There were no secondary fistulas, no secondary obstruction of the prosthesis. The longest follow-up was 69 months. CONCLUSION: The silicone prostheses used for the replacement of ureters are reliable and still permeable beyond 5 years. The protection of the renal function in patients often submitted to chemotherapy improves the duration and quality of survival. These prostheses must be reserved to advanced malignant diseases with a rather long life expectancy.     

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.     

Endoscopic treatment of oesophagoairway fistula with oesophageal balloon prosthesis

OBJECTIVE: To describe our experience with a cuffed oesophageal prosthesis in the management of malignant oesophagoairway fistulas. DESIGN: Retrospective study. SETTING: Teaching hospital, Denmark. SUBJECTS: Nine patients treated with a balloon cuffed oesophageal prosthesis during the period 1987-93. MAIN OUTCOME MEASURES: Endoscopic assessment of the fistula compared with the results and complications of treatment. RESULTS: The prosthesis were inserted without complications. Eight patients had total relief of aspiration and were able to eat a semisolid diet. Three patients needed reintervention. Patients with little or no stenosis of the tumour seemed to be at considerable risk of dislodgement of the tube and those with large fistulas developed protrusion of the balloon into the tracheal lumen. CONCLUSION: Intubation with the cuffed oesophageal prosthesis is safe and relatively inexpensive. Other treatments should be considered in patients with minor stenosis of the tumour or a large fistula.     

Endoscopic palliative treatment of a neoplastic esophageal fistula: report of a case

Oesophago-respiratory neoplastic fistulas present serious problems of management, because of the severe status of the patient. Therefore, a palliative treatment, to allow for a gradual respiratory and digestive function recovery with clinical improvements is needed. Surgical palliation has a mortality rate of 40% and a long post-operative hospitalization. Endoscopic palliation, on the other hand, has the same percentage of success of surgical palliation, but has the advantage to be performed in those patients with severe health conditions immediately improving the symptomatology and not excluding a subsequent surgical approach. The Authors present the case of a 70-year-old patient with a neoplastic relapse on the oesophago-gastric anastomosis, associated to an oesophago-respiratory fistula manifesting as severe dysphagia and dyspnoea. An endoscopic palliative treatment of the fistula was performed introducing a metallic coated prosthesis into the oesophagus. Severe clinical conditions regressed immediately and after 3 months they are unchanged. The Authors suggest endoscopic palliation with oesophageal prosthesis as the best therapeutic choice in those cases not amenable to surgery.     

Quality of life after knee arthroplasty. A randomized study of 3 designs in 42 patients, compared after 4 years

BACKGROUND: An initial multicenter study using a 21 mm flanged esophageal Z stent demonstrated excellent palliation but an 11% immediate complication rate at placement and a 27% migration rate at 1 month. This North American multicenter trial prospectively studied a 25 mm flanged Z stent to define its palliative ability and whether the increased diameter affected placement or migration problems. METHODS: Fifty patients who had esophageal Z stents at seven university or regional referral hospitals were prospectively studied. Indications for prosthesis placement, previous therapy, patient demographics, incidence of concomitant tracheoesophageal fistula, and degree of dysphagia were defined, as were procedural and subsequent stent-related problems, survival times, the ability to occlude a tracheoesophageal fistula, and subsequent degree of dysphagia. RESULTS: Twenty-four patients had infiltrating malignancy (16 exophytic and 10 extrinsic), 9 of whom had concomitant tracheoesophageal fistulas. Ten patients (20%) had misplaced stents requiring retrieval and replacement, 12 patients (24%) had subsequent stent-related problems including exsanguination (2), aspiration (3), tumor overgrowth (3), and postplacement migration (4) (8%). There was statistically significant improvement in prestent versus poststent dysphagia and two thirds of patients had complete occlusion of their tracheoesophageal fistula. CONCLUSIONS: Redesign of the esophageal Z stent has decreased the migration rate without increasing placement or subsequent erosion problems. Its efficacy appears comparable to the currently marketed Z stent for the palliation of malignant dysphagia and occlusion of tracheoesophageal fistula.     

Nitrate, ammonium, and phosphate uptake by the immobilized cells of Dunaliella salina

BACKGROUND: Three models of covered metal stents are available to seal esophageal fistulas. METHODS: Stainless steel covered stents were inserted in 5 patients (group I); nitinol covered stents were inserted in 12 patients (group II) with malignant (n = 14) or benign (n = 3) esophageal fistulas. RESULTS: Stent positioning was satisfactory in all cases. Fistula sealing was complete in 1 of 5 (20%) and 12 of 12 (100%) patients of groups I and II, respectively (p < 0.005). Continued esophageal leakage was initially related to the passage of fluids alongside the stent covering (n = 3) and to early stent migration (n = 1). Complications related to stent placement were observed in 2 of 17 (12%) patients and were fatal. During follow-up (mean 153 +/- 143 days), esophageal fistulas relapsed after initial sealing in 5 of 13 (38%) patients. Further treatment (glue or fibrin sealant injection, additional stent insertion) was attempted in 7 cases of persistent or relapsing esophageal fistula, with sealing obtained in 5 of them. The costs per patient and per day free from symptoms due to the esophageal fistula were $106 and $57 in groups I and II, respectively. CONCLUSION: Nitinol covered stents more frequently provided complete esophageal fistula sealing, as compared with stainless steel covered stents. Further treatments tailored to the mechanisms of fistula persistence or relapse often provided sealing.     

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.     

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.     

A new method for in vivo evaluation of biofilms on surface-modified silicone rubber voice prostheses

A new method is presented that permits a rapid and accurate in vivo evaluation of biofilm formation on surface-modified silicone rubber voice prostheses. The method is based on partial modification of a Groningen button voice prosthesis by exposing half of the prosthesis to an argon plasma. This results in one side of the prosthesis becoming hydrophilic while leaving the unmodified side hydrophobic as a control. Modified prostheses were placed in patients for an evaluation period of approximately 4 weeks. Despite making the silicone rubber surface hydrophilic, biofilm formation was stimulated when compared to unmodified, hydrophobic silicone rubber. Findings show that biofilm formation on voice prostheses is influenced by hydrophobicity of a silicone rubber surface. The method of partial surface modification used was seen to be suitable for demonstrating such influences regardless of nutrition and other variations in the patient's lifestyle. Microbiological analysis of the biofilms on both sides of the prosthesis valve did not show any changes in microbial composition, with Candida albicans, streptococci and staphylococci being the most commonly isolated strains.     

Interposition arthroplasty of the carpo-metacarpal joint of the thumb

Nine patients with osteoarthrosis of the carpo-metacarpal joint of the thumb were treated surgically with the metacarpo-trapezial silicone rubber prosthesis designed by Kessler. Patients with pantrapezoidal changes were specifically excluded. All patients at follow-up had chronic synovitis and in five the prosthesis was dislocated. In three patients who had revision operations the previously inserted prostheses were found to be badly torn.     

Renal blood flow: measurement in vivo with rapid spiral MR imaging

PURPOSE: To evaluate the use of stent-grafts for the percutaneous closure of arteriovenous fistulas that develop after cardiac catheterization. MATERIALS AND METHODS: From January 1994 to November 1997, 14 arteriovenous fistulas in 13 patients (eight men, five women; age range, 46-65 years; mean age, 53.5 years) were treated. Eleven fistulas were situated between the deep femoral artery and the common femoral vein, and three fistulas were between the superficial femoral artery and the common femoral vein. All fistulas were closed with stent-grafts positioned in the artery at the level of the fistula. RESULTS: The percutaneous treatment of arteriovenous fistulas was successful in all cases. The findings at angiography performed after the procedure demonstrated the closure of the fistulas and the correct positioning of the prostheses; veins were no longer visible. One complication occurred--a partial thrombosis of the common femoral vein at the puncture site after manual compression. CONCLUSION: On the basis of the preliminary data, the authors believe that the percutaneous closure of arteriovenous fistulas with stent-grafts is a safe and effective alternative to conventional surgery.     

Antibacterial activity of antibiotic coated silicone grafts

PURPOSE: Postoperative infection remains one of the most serious complications of implantation of penile prostheses. Attempts to reduce the rate of infection by spraying the prosthesis with an antibiotic solution prior to implantation, along with perioperative antibiotics, have failed to eradicate infection. No published studies have evaluated the effect of antibiotic coating of penile prostheses. In this study, we evaluate the antibacterial effect of antibiotic-coated silicone strips as a surrogate for the penile prosthesis. MATERIALS AND METHODS: Strips coated with several different antibiotics were dipped in bacterial solutions containing Staphylococcus epidermidis or S. aureus and implanted subcutaneously in adult Sprague-Dawley rats. After a week, the strips were removed, and the number of bacteria on the strips and in the surrounding tissue were determined. The in vitro antibiotic activity of the antibiotic-coated strips against the same organisms was also determined. RESULTS: In the group of rats that received silicone strips contaminated in vitro with S. epidermidis, six of nine control rats yielded strips and tissues containing heavy bacterial growth. None of six strips coated with rifampin/minocycline yielded bacterial growth, nor did any of the seven strips coated with vancomycin. One of seven rats that received amikacin-coated strips had infection of the strip. The tissue results were similar to the strip results. In the group using S. aureus as the contaminating bacterium, the strips and tissues from eight of nine control rats yielded bacteria. None of the six rifampin/minocycline-coated strips yielded bacteria, while two of seven vancomycin-treated strips and two of six amikacin-coated strips were infected with S. aureus. The difference in bacterial growth between controls and antibiotic-coated strips reached a level of statistical significance for the rifampin/minocycline and vancomycin groups and was highly significant for the rifampin/minocycline groups. CONCLUSION: The experimental results presented here suggest that coating silicone graft material with antibiotics, particularly rifampin/minocycline, can reduce the incidence of graft colonization in contaminated wounds in rats, even in the absence of systemic antibiotics. These graft materials may prove useful in preventing the infection of penile prostheses.     

Head and neck replacement endoprosthesis for pathologic proximal femoral lesions

Records of 28 patients with pathologic lesions in the proximal femur treated by implantation of a femoral head and neck replacement prosthesis between 1984 and 1995 were reviewed. Mean clinical followup was 47.8 months in the eight living patients and 15.8 months in the 20 patients who had died. The underlying diagnosis was metastatic disease or myeloma in 22 patients. The most frequently occurring indication for implantation of this device was a pathologic fracture in 26 patients (18 displaced, eight impending), followed by resection and reconstruction in two patients. All femoral components were cemented: 23 were bipolar hemiarthroplasties and five were total hip arthroplasties. Implant survivorship was good (93%), with only two prostheses removed during the followup period, both for infection. However, radiographic analysis revealed increasing lucencies with time, particularly in the most proximal zones, resulting in radiographic failure in an additional case. Deep infection occurred in three cases, leading to resection arthroplasty in two patients. Periprosthetic fractures occurred in three cases, but only one occurred intraoperatively. Despite a high complication rate, the good implant survival during the shortened life span of these patients supports the continued use of femoral head and neck replacement prostheses in this population.     

Voice prostheses with sound-producing metal reed element--an experimental study and initial clinical results

BACKGROUND: Following total laryngectomy the voice is produced by esophageal speech as well as with voice prostheses by vibrations of pharyngeal mucosal folds. This pharyngeal sound normally has a significantly lower fundamental frequency than the healthy voice (men about 120 Hz, women about 240 Hz, pharyngeal voice about 70 Hz), which is a handicap especially for female laryngectomy patients. In order to improve the postlaryngectomy voice, a new type of voice prostheses containing an integrated sound-producing metallic reed element was developed (ADEVA Company, Lübeck, Germany). METHODS/PATIENTS: Thirty-five of these new sound-producing voice prostheses were tested in vitro for different prosthesis-specific physical parameters (pressure, flow, sound pressure, flow resistance, frequency range). In 15 voice prosthesis speakers, a sound-producing prosthesis was introduced during a routine outpatient visit. Besides measurement of the above mentioned physical parameters in patients with conventional and sound-producing prostheses, the resulting voice as also evaluated by means of a video recording. RESULTS: In vitro all prostheses with the metallic reed element produced a clear sound. Flow resistance of the prostheses was slightly elevated by the reed element. Insertion of the prostheses was hindered by the reed element. Period of uninterrupted sound production was prolonged after insertion of a sound-producing prosthesis and patients could speak on a lower pressure level, but the sound of the reed element was permanently distinguishable only in 6 of 15 patients. CONCLUSIONS: In principle a variation of the pharyngeal voice by means of a sound producing element, which is integrated into a voice prosthesis, is possible. The current design of the metallic reed element tested is not yet suitable for routine clinical use: 1. The reed element is too sensitive and is easily damaged during insertion, so the insertion device has to be improved. 2. The sound producing element is blocked by small amounts of tracheal secretions, so that this element should be replaceable separately without requiring removal of the silicone value (if possible by the patient himself). Prior to insertion of the sound producing voice prosthesis the maximum air flow through the shunt should be measured to determine if the patient can produce the necessary air flow for activation of the reed element. A further improvement for these special types of voice prostheses would be a sound producing element, which generates a variable frequency of sound. Limiting the patient to only one fundamental frequency creates a monotone, which does not sound naturally. Initial progress toward a sound-producing voice prostheses has been made. This should be followed by the necessary improvements in order to improve the feasibility of this design for routine clinical use.     

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.     

Orbital involvement in Wegener granulomatosis: MR findings in 12 patients

Device life of tracheoesophageal voice prostheses is limited due to deterioration of the polymers. A group of 55 postlaryngectomy patients fitted with a Provox voice prosthesis have been studied prospectively during 6 months. Thirty-seven prostheses were replaced due to a dysfunctional valve mechanism. Although colonization with Candida species was highly associated with destruction of the silicone material, other upper respiratory tract commensals, e.g. Staphylococcus aureus, were also demonstrated. Electron microscopy of the contaminated devices showed colonization and disruption of the silicone material by penetrating yeast hyphae. During the study a remarkable increase of intratracheal phonatory pressures was assessed with progressive colonization of the prostheses.     

Clinical experience with Dynaflex penile prostheses in 120 patients

OBJECTIVES: To present our experience with the Dynaflex (American Medical Systems) self-contained inflatable penile prosthesis and define specific complication and patient dissatisfaction rates. METHODS: From May 1990 through January 1998, 120 men underwent implantation of a Dynaflex prosthesis. The follow-up period ranged from 2 to 80 months (mean 42). RESULTS: Specific complication rates observed after penile prosthesis implantation were as follows: prosthetic infection, 4.16%; mechanical device failure, 7.5%; and patient dissatisfaction because of inability to work the pump, 16.66%. After intensive teaching, the patient dissatisfaction rate dropped to 0.83%. The overall complication rate was 14.15%. CONCLUSIONS: With several types of penile prostheses available, Dynaflex can be regarded as an appropriate alternative with a relatively low mechanical failure rate. However, careful preoperative assessment and patient education in the use of the pump mechanism are essential to obtain a successful result.     

Urinary fistula after transplantation: eleven cases

OBJECTIVES: To specify the anatomical features of urinary fistulas and to evaluate the results of percutaneous and surgical treatment of post-transplantation urinary fistulas. PATIENTS AND METHODS: 11 urinary fistulas were observed after 160 renal transplantations, corresponding to an incidence of this complication of 6.8%. Urinary fistulas were treated percutaneously in three cases and surgically in eight cases. THE FOLLOWING COMPLICATIONS WERE OBSERVED DURING SURGICAL TREATMENT: extensive necrosis of the urethra in four cases, rupture of the sutures in two cases, a punctate pelvic fistula in one case. RESULTS: The incidence of fistula was 5.8% for Leadbetter reimplantation and 8.1% for Lich-Gregoir extravesical reimplantation. We obtained one success in three patients treated percutaneously and one death and seven successes out of eight patients treated surgically. We performed ureteropelvic anastomosis with the native ureter in the case of extensive necrosis of the ureter (4 cases), a new reimplantation in three cases and suture of the pelvic fistula in one case. CONCLUSION: More than one half of post-transplantation urinary fistulas observed in our department are secondary to ischaemic necrosis of the ureter. We emphasize the value of preservation of the ureteric blood supply during organ harvesting. Post-transplantation urinary fistulas must be treated surgically, as soon as possible, to avoid infectious complications.     

Health risks for women with breast implants

Women who have undergone implantation of a breast prosthesis have been exposed to a variety of health risks, many of which were unknown to them at the time of surgery. Recognition of health hazards has prompted the Food and Drug Administration to restrict implantation of these devices while study of safety and efficacy are undertaken. Capsule contracture, or the contraction of the fibrous tissue surrounding the prosthesis, is the most frequently occurring complication. Exposure to an implant does not appear to heighten the risk for breast cancer, but the opacity of a prosthesis substantially reduces the diagnostic capability of mammography. Silicone, used in the manufacture of implants, is linked to immunologic changes that result in connective tissue disorders. Most often this condition is scleroderma. Damaging effects from toluenediamine, a disintegration product of the polyurethane coating, have been reported. Whether the concentration of this chemical reaches toxic levels in women with prostheses remains to be clarified by current investigations.