PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “virtual intervention”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 379 records · Page 21Linked to original sources

Computer-based simulator for catheter insertion training.

Minimally invasive surgery procedures are getting common in surgical practice; however the new interventional procedure requires different skills compared to the conventional surgical techniques. The need for training process is very important in order to successfully and safely execute a surgical procedure. Computer-based simulators, with appropriate tactile feedback device, can be an efficient method for facilitating the education and training process. In addition, virtual reality surgical simulators can reduce costs of education and provide realism with regard to tissues behaviour and real-time interaction. This work take into account the results of the HERMES Project (HEmatology Research virtual MEdical System), conceived and managed by Consorzio CETMA-Research Centre; the aim of this project is to build an integrate system in order to simulate a coronary angioplasty intervention.

Catheters, Indwelling↗

The treatment of end-stage liver disease in childhood.

With the availability of orthotopic liver transplantation as a definitive treatment option for most cases of end-stage liver disease in children, there is renewed interest in this hitherto universally fatal condition. The potential for long-term survival after liver transplantation without disability is a realistic prospect for the majority, although the surgery is one of the most difficult surgical procedures available and represents a daunting prospect. The success of liver transplantation (80% one year and approximately 70% five year survival) has required virtually a re-definition of the diagnosis of end-stage liver disease with a view to predicted outcome and timely intervention. This includes a more aggressive approach to supportive treatment in order to maintain (if not improve) the patient's clinical status, if the treatment option of transplantation is decided upon. Preferably this treatment option should be considered and offered immediately the condition of end-stage liver disease is realised, in order to allow time for full and frank discussion of treatment options, to optimize supportive therapy, to evaluate suitability for liver transplantation and to maximize prospects of obtaining a donor organ. In Australia, particularly in children, liver transplantation is limited by the scarcity of suitable donor organs, although the development of reduction hepatectomy of an adult organ has allowed access to a much larger donor pool. This development has particular advantages in Australia, allowing organs from 80 kg adults to be transplanted successfully into 5 kg or 6 kg infants and has, at the time of writing, virtually eliminated potential paediatric recipient deaths while awaiting a suitable donor.

Acute Disease↗

Vascular access complications after cardiac catheterisation: a nurse-led quality assurance program.

BACKGROUND: Vascular access complications may be a cause of discomfort, prolonged hospital stay, and impaired outcomes in patients undergoing cardiac catheterisation. AIMS: To assess vascular access complication in our patients with/without the use of closure devices as a first local benchmark for subsequent quality improvement. METHODS: A nurse-led single-centre prospective survey of all vascular access complications in consecutive patients submitted to cardiac catheterisation during 4 months. RESULTS: The radial and femoral access were used in 78 (14%) and 470 (83%), respectively, of 564 procedures, and a closure device was used in 136 of the latter. A haematoma (any size) was isolated and uneventful in 9.6% of cases. More severe complications (haemoglobin loss >2 g, need for blood transfusion or vascular repair) occurred in 1.2% of cases, namely: in none of the procedures with radial access, and in 0.4% and 2.4% of femoral diagnostic and interventional coronary procedures, respectively. During complicated (n=40) vs uncomplicated (n=172) transfemoral interventions, the activated coagulation time was 309+/-83 vs 271+/-71 s (p=0.004), but the use of closure devices was similar. CONCLUSION: Severe vascular access complications in our patients were fewer than in most reports, and virtually absent in radial procedures. Vigorous anticoagulation was associated with increased complications in our patients, but closure devices were not. A new policy including both the use of the radial access whenever possible, and a less aggressive anticoagulation regimen during transfemoral interventions will be tested.

Aged↗

[MR-track pointer. A reusable device for localization during interventions].

PURPOSE: Development of an helpful instrument for a better planning and orientation during MR guided interventions. MATERIAL AND METHODS: We developed a reusable, sterilizable instrument that can be filled both with a solution of Gd-DTPA (1%) and with a sodium chloride solution (0.9%). The pointer has a diameter of 3 and 5 mm resp. and its length is 100-150 mm. The instrument can be combined with an interactive stereotactic tracking device. RESULTS: The MR-Track-Pointer can be fixed to the two handpieces of the integrated interactive tracking system without problems. The pointer can be seen both on T1w and T2w sequences inside and outside of the tissue. This new instrument can be interactively used for reliable planning the biopsy trajectory, planning craniotomies and identifying structures which are only visible on MR images. CONCLUSIONS: The MR-Track-Pointer is an ideal supplement for the integrated virtual tracking system. It permits a minimal invasive orientation and facilitates the exact localisation of suspect lesions in sensible regions during MR guided interventions, e.g. diagnostic biopsies and tumour resections.

Biopsy↗

Psychosocial aspects of surrogate motherhood.

This review addresses the psychosocial research carried out on surrogacy triads (surrogate mothers, commissioning mothers and offspring) and shows that research has focused on a number of specific issues: attachment and disclosure to surrogate offspring; experiences, characteristics and motivations of surrogate mothers; and changes in profiles of the commissioning/intended mothers. Virtually all studies have used highly selected samples making generalizations difficult. There have been a notable lack of theory, no interventions and only a handful of longitudinal studies or studies comparing different populations. Few studies have specifically questioned the meaning of and need for a family or the influence and impact that professionals, treatment availability and financial factors have on the choices made for surrogate and intended mothers. Societal attitudes have changed somewhat; however, according to public opinion, women giving up babies still fall outside the acceptable remit. Surrogate and intended mothers appear to reconcile their unusual choice through a process of cognitive restructuring, and the success or failure of this cognitive appraisal affects people's willingness to be open and honest about their choices. Normal population surveys, on the contrary, are less accepting of third party reproduction; they have no personal need to reconsider and hence maintain their original normative cognitively consonant state.

Family Relations↗

Advances in abdominal MR imaging.

Major technical advances in MR imaging have led to its wider use in the evaluation of abdominal disease. The principle new pulse sequence is the RARE sequence for T2-weighted imaging. Multishot and breath-hold single-shot RARE techniques are now widely used, and both have performed as well as conventional spin-echo imaging with far shorter acquisition times. The most notable improvements have been in the detection and characterization of hepatic lesions. Two liver-specific contrast agents received FDA approval during 1997: SPIO particles or ferumoxide and mangafodipir trisodium, a hepatocyte-specific agent. Both of these agents provide considerable benefit in the detection and characterization of hepatic lesions. Manganese enhancement has also proved useful in MR imaging of the pancreas, although fat-suppressed T1-weighted imaging with dynamic gadolinium enhancement has also yielded results comparable with those of contrast-enhanced CT. MR hydrography, a generic term for static fluid imaging, is another derivative of RARE fast T2-weighted imaging. MRCP, the best known example of MR hydrography, has been rapidly and widely employed as a primary method for imaging the biliary and pancreatic ducts and has become competitive with ERCP. MR vascular imaging, especially portal venography, has been used for noninvasive imaging of portal venous disease in Budd Chiari disease, before placement of transjugular intrahepatic portosystemic shunts, and for pancreatic cancer staging. Finally, the development of conventional phased-array body coils and endorectal coils has enabled high-quality MR imaging of perirectal disease (including Crohn disease, fistula in ano, and postpartum sphincter dysfunction). Future abdominal applications of MR imaging will involve second-generation MR interventional techniques, including use of open systems, functional or diffusion-weighted imaging exploiting the molecular activity of tissues, and virtual MR endoscopy. Although CT continues to evolve as the premier technique for survey screening of the abdomen, the technical advances in MR imaging have enabled this modality to assume some special nitch roles (in which it adds unique value) in the evaluation of the abdomen. Radiologists can safely assume that there will undoubtedly be much more to come.

Abdomen↗

Chronic proteinuric nephropathies. II. Outcomes and response to treatment in a prospective cohort of 352 patients: differences between women and men in relation to the ACE gene polymorphism. Gruppo Italiano di Studi Epidemologici in Nefrologia (Gisen)

In the Ramipril Efficacy in Nephropathy study, ramipril decreased the rate of GFR decline (deltaGFR) and progression to end-stage renal disease (ESRD) in 352 patients with proteinuric chronic nephropathies. This study investigated whether in these patients disease outcome and response to treatment were affected by gender or insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene. deltaGFR (0.43 +/- 0.05 versus 0.48 +/- 0.08 ml/min per 1.73 m2) and incidence of ESRD (23 and 22%, respectively) were comparable in male and female patients. However, compared to conventional treatment, ramipril decreased deltaGFR (-52% versus -19%) and progression to ESRD (-74% versus -40%) more effectively in women than in men. Thus, the relative risk (95% confidence interval [CI]) of events (ESRD) between conventional and ramipril treatment was 5.52 (1.59 to 19.17, P = 0.003) in women, but only 1.80 (1.08 to 2.97, P = 0.02) in men. This gender-related effect of ramipril was associated with more reduction in proteinuria (-7.8 +/- 4.2% versus -21.9 +/- 5.7%, P = 0.05) and was still evident even after correction for potentially confounding factors such as baseline GFR, daily sodium intake, ramipril dose, BP control, and concomitant treatment with diuretics or dihydropyridinic calcium channel blockers (adjusted RR [95% CI]: women, 5.07 [1.26 to 20.38], P = 0.02; men, 1.44 [0.85 to 2.44], P = 0.17). Ramipril uniformly decreased deltaGFR and incidence of ESRD in women with either DD (-39% and - 100%) or II + ID (-71% and -82%) genotype, and in men (-25% and -50%) with the DD genotype, but had no beneficial effect in men with the II + ID genotype (+18% and +34%). Thus, the relative risk of events (ESRD) between conventional and ramipril-treated men was higher in subjects with the DD genotype (1.85; 0.69 to 4.94) and lower in those with the II +/- ID genotype (0.71; 0.28 to 1.80). Again, in parallel with deltaGFR and events, proteinuria decreased in women with DD (-23.3 +/-8.0%) or II + ID (-16.0 +/- 9.5%) genotype and in men with the DD genotype (-14.8 +/- 7.0%), but did not change in men with II + ID genotype (+ 1.0 +/- 7.8%). Of note, the ACE genotype-related effect of ramipril was still evident even after correction for the above potentially confounding factors (adjusted RR [95% CI]: DD, 2.52 [0.83 to 7.63], P = 0.10; II + ID, 0.35 [0.12 to 1.01], P = 0.05). Thus, among patients with chronic proteinuric nephropathies, men are at increased risk of progression due to their lower response to ACE inhibitor treatment. ACE inhibition is uniformly renoprotective in women regardless of the ACE polymorphism, and in men with the DD genotype, but is virtually devoid of beneficial effects in men with the II or ID genotype. This information may help to guide therapeutic interventions in clinical practice and to interpret the results of prospective trials in chronic renal disease.

Adolescent↗

An interactive media program for managing psychosocial problems on long-duration spaceflights.

Space crews must be self-reliant to complete long-duration missions successfully. This project involves the development and evaluation of a network of self-guided interactive multimedia programs to train and assist long-duration flyers in the prevention, assessment, and management of psychosocial problems that can arise on extended missions. The system is currently under development and is intended for use both during training and on orbit. A virtual space station 3-dimensional graphic was created to serve as a portal to multimedia-based training, assessment, and intervention resources. Additionally, original content on interpersonal conflict and depression is being developed for the system. Input on the best practices for managing conflict and depression on extended missions was obtained from 13 veteran long-duration flyers, as well as from clinical experts. Formative evaluation of a prototype of the system will be conducted with 10 members of the astronaut corps. Subsequently, the content on conflict and depression will be completed, and the depression self-treatment portion will be evaluated in a randomized controlled trial. Although this study involves developing countermeasures to assist long-duration flyers, it also provides a model that could be applied in many Earthbound settings, both in operational environments and in everyday life.

Aerospace Medicine↗

Evaluation and management of apparent life-threatening events in children.

Apparent life-threatening event syndrome predominantly affects children younger than one year. This syndrome is characterized by a frightening constellation of symptoms in which the child exhibits some combination of apnea, change in color, change in muscle tone, coughing, or gagging. Approximately 50 percent of these children are diagnosed with an underlying condition that explains the apparent life-threatening event. Commonly, the problems are digestive (up to 50 percent), neurologic (30 percent), respiratory (20 percent), cardiac (5 percent), and endocrine or metabolic (less than 5 percent). Fifty percent of these events are idiopathic, which causes great concern to parents and physicians. The evaluation of an affected infant involves a thorough description of the event as well as prenatal, birth, medical, social, and family history. The physical examination, including careful neurologic examination and notation of any apparent anatomic abnormalities, helps diagnose congenital problems, infection, and conditions contributing to respiratory compromise. The laboratory evaluation is driven by historical and physical findings. Inpatient evaluation and monitoring are recommended in virtually all cases unless investigations are normal. Should the history reflect a severe episode, or should the child require major interventions such as cardiopulmonary resuscitation, inpatient observation and monitoring are recommended, even if physical examination and laboratory findings are normal. Once a presumptive diagnosis is made, events should cease after appropriate intervention. If not, reviewing the history, performing another physical examination, and reassessing the need for laboratory and imaging studies are the next steps. Although consensus statements by the National Institutes of Health and the American Academy of Pediatrics support home monitoring, the relationship of apparent life-threatening event syndrome to sudden infant death syndrome is controversial.

Apnea↗

Impact of alcohol-based, waterless hand antiseptic on the incidence of infection and colonization with methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci.

OBJECTIVE: Colonized and infected inpatients are major reservoirs for methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE), and transient carriage of these pathogens on the hands of healthcare workers remains the most common mechanism of patient-to-patient transmission. We hypothesized that use of alcohol-based, waterless hand antiseptic would lower the incidence of colonization and/or infection with MRSA and VRE. METHODS: On June 19, 2001, alcohol hand antiseptic was introduced at the University campus and not the nearby Memorial campus of the University of Massachusetts Medical School (Worcester, MA), allowing us to evaluate the impact of this antiseptic on the incidence of MRSA and VRE colonization and infection. From January 1 through December 31, 2001, the incidence of MRSA colonization or infection was compared between the 2 campuses before and after the hand antiseptic was introduced. Its effect on VRE colonization and infection was only studied in the medical intensive care unit at the University campus. RESULTS: At the University campus, the incidence of MRSA colonization or infection decreased from 1.26 cases/1,000 patient-days before the intervention to 0.75 cases/1,000 patient-days after the intervention, for a 1.46-fold decrease (95% confidence interval, 1.04-2.58; P = .037). At the Memorial campus, the incidence of MRSA colonization or infection remained virtually unchanged, from 0.34 cases/1,000 patient-days to 0.49 cases/1,000 patient-days during the same period. However, a separate analysis of the University campus data that controlled for proximity to prevalent cases did not show a significant improvement in the rates of infection or colonization. The incidence of nosocomial VRE colonization or infection before and after the hand antiseptic decreased from 12.0 cases/1,000 patient-days to 3.0 cases/1,000 patient-days, a 2.25-fold decrease (P = .018). Compliance with rectal surveillance for detection of VRE was 86% before and 84% after implementation of the hand antiseptic intervention. The prevalences of VRE cases during these 2 periods were 25% and 29%, respectively (P = .017). CONCLUSIONS: Alcohol hand antiseptic appears to be effective in controlling the transmission of VRE. However, after controlling for proximity to prevalent cases (ie, for clustering), it does not appear to be more effective than standard methods for controlling MRSA. Further controlled studies are needed to evaluate its effectiveness.

Alcohols↗

Modality-based navigation.

Modality-based navigation (MBN) means the interactive tracking of instruments in a co-ordinate system defined by an imaging modality, eg, CT, MR, or a fluoroscope. During the registration process, a transformation matrix between the two co-ordinate systems of the digitizer and imaging modality is calculated. Navigation can start immediately after collection of the images without an intraprocedural registration process. Since the imaging modality belongs to the OR or the intervention suite, image update can be performed at any time. Following a step-by-step procedure with navigation and image update in a reasonable sequence, the risk for a virtual-real mismatch is minimized. For CT-MBN, we obtained a freehand absolute positioning accuracy of 1.9+/-1.1 mm in vitro. The in vivo freehand absolute positioning accuracy in pelvic fracture fixation was determined to be 3.1 mm (unpublished data). From our point of view, modality-based navigation is an efficient and safe alternative tool for computer aided interventions.

Fluoroscopy↗

[Acute STEMI in old and very old patients. The real life].

OBJECTIVES: From a prospective multicenter registry, we evaluated in three non-academic interventional cardiologic centers (Alsace/France), the coverage and the feasibility of the percutaneous coronary angioplasty (PTCA) in the acute phase of STEMI in the elderly (patients 75-years old and more). METHODS: We studied clinical characteristics and angiographic data of patients older than 75 years, and the PTCA results: the revascularisation rates and the intrahospital events were analysed. These data were compared with those of the younger patients and confronted with the literature data. RESULTS: Of a total of 1672 patients admitted for a STEMI, 342 (20.45%) were older than 75 years. These patients represented a high-risk group with a high proportion of women (50%), and many co-morbidities (e.g.: hypertension and diabetes mellitus), and three-vessel disease was found more often than in younger patients. Mortality rate was high in this subgroup and always more severe as compared to younger subjects, but remains variable according to the initial clinical profile. The global mortality was 20.47% but fell to 5.41% if we excluded the patients with cardiogenic shock, in Killip III and after resuscitation. PTCA is a coronary reperfusion technique particularly indicated in the management of the elderly presenting a STEMI. It is an effective technique in term of revascularisation, the reperfusion success (exclusively TIMI III flow) was indeed raised in the elderly even though it is lower than in younger patients (93.88 vs 97.18%). It is a quickly accessible technique, cath-lab accessibility provided, allowing a fast reperfusion and reducing hospitalization to a minimum. The management of the elderly presenting a STEMI has to focus on reducing the preadmission delay since this subgroup of patients hesitates to call the emergency (SMUR) when presenting an acute coronary symptomatology. The shorter the delay till admittance, the better the outcome. CONCLUSION: PTCA is a technique particularly indicated in the elderly in Alsace because of regional specificities: first of all geographic (proximity of the SMUR for virtually all the population of Alsace), and secondly the medical infrastructure since the strategy of exclusive primary PTCA is granted by numerous interventional cardiologic teams. In Alsace, the proportion of elderly patients (> or = 75 years) is going to increase significantly with a parallel rise of STEMI--"a frightening perspective". We have to take into account this evolution, this reperfusion technique presenting numerous advantages and very few complications.

Aged↗

Experiences and Behavior During a Virtual Reality Buffet Simulation: A Secondary Analysis of a Ghrelin-Related Pharmacology Randomized Controlled Trial in People with Alcohol Use Disorder.

BACKGROUND: Virtual reality (VR) can deliver standardized, ecologically valid assessments while capturing nuanced psychological and behavioral outcomes. Sensitivity of VR assessments to pharmacological interventions, however, has seldom been tested. METHODS: We conducted a secondary analysis of a randomized, double-blind, placebo-controlled, crossover study evaluating a growth hormone secretagogue receptor (GHSR, the ghrelin receptor) blocker (PF-5190457) in people (N = 29) with alcohol use disorder. The previously reported primary study results demonstrated that the GHSR blocker did not reduce alcohol cue-elicited craving but did reduce the number of calories selected in a VR buffet food choice assessment. Here, we investigated the impact of the drug on experiences and behavior in the VR buffet. RESULTS: Participants reported higher levels of liking the VR, more typicality, and more satisfaction with their food choices under the GHSR blocker than the placebo. We also found that participants who were given the placebo first took longer to make a decision about the food they should eat and were also more likely to go up for a second serving of food when on the placebo. This was significantly less likely for participants who were given the GHSR blocker. CONCLUSIONS: The present results suggest that the GHSR blocker influenced experiences and behavior in the VR buffet in ways that are conceptually consistent with the known real-world effects of blocking the ghrelin system. These findings support the validity of using VR buffets as proxies for real-world measurements in pharmacology contexts.

alcohol use disorder↗

Supermarket tour: the effect of presentation mode on nutrition knowledge and attitudes.

BACKGROUND AND OBJECTIVES: A supermarket tour is an interactive experience in which students learn nutrient composition of common foods, requirements for various nutrients, issues related to eating behaviors, diseases associated with nutrient intake, and how food marketing, labeling, and regulation influence what people choose to eat. This study determined if presentation mode of a supermarket tour influenced medical students' nutrition knowledge and attitudes. METHODS: Senior medical students received nutrition instruction in one of four presentation modes: live (n=11), small-group 2-hour virtual (n=8), large-group 2-hour virtual (n=69), and large-group virtual in four half-hour sessions across 4 days (n=37). The same instructor gave all tours. Students completed pre- and post-course evaluations and knowledge tests. RESULTS: After the intervention, students participating in live and single-session groups had greater nutrition knowledge than the students participating in the extended course. Students in small groups also had higher confidence in giving nutrition advice. There was no difference among the four groups for enthusiasm. Students gave a higher recommendation to the live mode than to the extended version. CONCLUSIONS: The virtual tour is effective at improving knowledge, engaging, and provides information that students may use for themselves and their patients. Single-session live teaching is most well received.

Education, Medical, Graduate↗

Live donor adult liver transplantation using right lobe grafts: donor evaluation and surgical outcome.

HYPOTHESIS: Live donor adult liver transplantation (LDALT) is a safe and efficacious treatment for patients with end-stage liver disease. DESIGN: Case-control study. SETTING: Hepatobiliary surgery and liver transplantation unit. PATIENTS: From December 10, 1998, through April 10, 2000, a single team performed 15 LDALT procedures with 2 simultaneous living donor kidney transplants. During this period, 66 potential donors were screened and evaluated. INTERVENTIONS: Potential donors were evaluated with 3-dimensional helical computed tomographic scan, including volume renderings for hepatic lobar volume, vascular anatomy, virtual resection planes, and morphologic features. Suitable donors undergo complete medical and psychiatric evaluation and preoperative arteriography. MAIN OUTCOME MEASURES: Donor demographics, evaluation data, operative data, hospital length of stay, and morbidity. RESULTS: A total of 38 men (58%) and 28 women (42%) were evaluated with 15 donors participating in LDALT. Two additional donors provided kidney grafts for simultaneous transplantation at the time of LDALT. Thirty-two donors (48%) were rejected for either donor or recipient reasons, and 10 patients (15%) elected not to participate after initial screening. Three-dimensional volume renderings by helical computed tomographic scan predicted right lobe liver volume within 92% of actual graft volume. Donor morbidity, including all complications, was 67% with no mortality. Residual liver regenerated to approximately 70% of initial volume within 1 week and 80% within 1 month after surgery. CONCLUSIONS: Donor evaluation is an important component of LDALT. Significant donor morbidity is encountered even with careful selection. To minimize donor morbidity, groups considering initiating living donor programs should have expertise in hepatic resection and vena cava preservation using the "piggyback" technique during liver transplantation.

Adolescent↗

Major differences in the pulmonary circulation between birds and mammals.

The lungs of domestic chickens were perfused with blood or dextran/saline and the pulmonary artery pressure (P(a)) and venous pressure (P(v)) were varied in relation to air capillary pressure (P(A)). In Zone 3 conditions, pulmonary vascular resistance (PVR) was virtually unchanged with increases in either P(a) or P(v). This is very different behavior from mammals where the same interventions greatly reduce PVR. In Zone 2 conditions blood flow was essentially independent of P(v) as in mammalian lungs but all the capillaries appeared to be open, apparently incompatible with a Starling resistor mechanism. In Zone 1 the capillaries were open even when P(A) exceeded P(a) by over 30 cm H(2)O which is very different behavior from that of the mammalian lung. We conclude that the air capillaries that surround the blood capillaries provide rigid support in both compression and expansion of the vessels. The work suggests a pathogenesis for pulmonary hypertension syndrome in chickens which costs the broiler industry $1 billion per year.

Animals↗

Use of metallic stents and balloons in the esophagus and gastrointestinal tract.

The majority of malignant and benign strictures in the esophagus and GI tract can be treated with use of minimally invasive alternatives to surgery such as balloon dilation or metallic stents. Virtually any obstructing lesion in the esophagus, stomach, duodenum, colon, and rectum can be treated with these methods with use of interventional radiologic or endoscopic techniques. In general, metallic stents are reserved for malignant strictures and balloon dilation is indicated for benign lesions. Patients with malignant esophageal fistulas and perforations can be palliated effectively and promptly by sealing the fistula or leak by deployment of a covered stent. Patients with malignant disease may benefit from a treatment regime that includes metallic stent placement, chemotherapy, radiation therapy and/or brachytherapy, although the efficacy of such combined therapies has yet to be defined. Further refinements to stent design are required. The ideal stent would be resistant to tumor ingrowth and migration. Placing a coating material on uncovered stents to prevent tumor ingrowth may achieve these aims. Finally, a biodegradable stent that dissolves before the development of intimal hyperplasia might enable stents to be used to treat benign strictures.

Catheterization↗