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At least 235 records · Page 13Linked to original sources

Retrieval of a malpositioned vena cava filter with embolic protection with use of a second filter.

Proper positioning of inferior vena cava (IVC) filters is necessary for effective protection from pulmonary embolism (PE). This report describes a case of an IVC filter malpositioned partially in the right common iliac vein that resulted in risk of recurrent PE caused by thrombus emanating from the left common iliac vein. A new filter was placed in the IVC above the first device, followed by retrieval of the malpositioned filter through the new filter.

Catheterization, Central Venous↗

Analysis of the postoperative outcome in 405 cases of orbital fracture using 2 synthetic orbital implants.

The purpose of this study was to analyze the postoperative complications according to the location (floor/medial wall/floor and medial wall) of the orbital fracture of 405 patients during the past 10 years and to investigate the possible alterative data in postoperative outcome in change with the application of 2 synthetic orbital implants: porous polyethylene (Medpor) and hydroxyapatite (Biocoral). The medical records of 405 patients were reviewed especially for enophthalmos, diplopia, sensory disturbance in the area of distribution of the infraorbital nerve, and postoperative complications originated from the implanted material itself, from March 1993 to July 2003. Of the 405 patients, 214 patients were operated with porous polyethylene and 191 patients with hydroxyapatite. The complication rate of the porous polyethylene group was 5.6%, which was not statistically different from that of the hydroxyapatite group (9.4%). Also by the location of fracture, the complication rate of both groups was similar statistically. In the comparative category, enophthalmos was more frequent statistically in patients treated with hydroxyapatite than those treated with porous polyethylene, and no other significant differences were in postoperative outcomes between the both groups. The information provided in this report should aid in using porous polyethylene or hydroxyapatite for reconstruction of the orbital fracture and in accomplishing better postoperative outcome.

Adolescent↗

Relining an ocular prosthesis: a case report.

There are times when a patient who has an ocular prosthesis may need surgery to correct an anophthalmic socket defect or to replace an implant. When such a situation arises, it may not be possible to construct a new prosthesis soon after surgery. In this article, a technique for relining an ocular prosthesis is described.

Acrylic Resins↗

Lead interaction: rare cause of oversensing during implantation procedure of implantable cardioverter-defibrillator system.

A variety of etiologies can cause erroneous detection in patients with implantable cardioverter defibrillator (ICDs). Interaction between two endocardial leads is rare and uncommon in causing electrical noise. During a reimplantation procedure of an ICD system in a 68-year-old man, additional electrical signals could be detected. The interaction between two endocardial defibrillation leads was identified as the cause of sensing problems. When it is not possible to extract the nonfunctional endocardial lead during implantation of the new electrode, it should be implanted away and not in parallel from the old one to avoid interaction between them. A variety of etiologies can cause erroneous detection in patiens with ICD. Interaction between two endocardial leads is rare and uncommon to cause electrical noise.

Aged↗

Dysfunction of an atrial septal defect occluder 8 years after implantation.

Catheter interventional treatment of atrial septal defect (ASD) is widely accepted. The ASD occluder system (ASDOS) is no longer a widely used device nowadays. However, it is implanted in a substantial number of patients. We report a case of severe left-to-right shunt 8 years after catheter interventional closure of an ASD with an ASDOS device. The shunt was due to a membrane perforation, while the arms of the device were not dislocated. Microscopy, microbiology, and histology could not establish a proper explanation for the dysfunction; so long-term follow-up investigation may be required in patients with an implanted ASDOS device.

Aged↗

Optimization of design and surgical positioning of inflatable penile prostheses.

The interaction between the cylinders of an inflatable penile prosthesis (IPP) and the surrounding tissues during IPP-aided erection may result in local elevated stresses. These stresses may reach values that can obstruct penile blood vessels and cause ischemia and/or stimulate nerves around the operation site, thereby inducing sensations of pain. A new numerical model was used to analyze penile stresses postimplantation of different IPP types, in order to optimize prosthesis design and surgical positioning by enabling minimal stress transfer to dorsal blood vessels and nerves. The results suggest that intraluminal pressures should be maintained at low levels (about 80 kPa) while cylinder thickness and stiffness should be kept just high enough (approximately 15% of the radius and 1000 MPa, respectively) to eliminate deleterious cylinder-tissue contact stresses. Smaller prosthetic cylinders, i.e., occupying about 45% of the cavernosal space, may be advantageous in terms of reducing dorsal stresses, but lower penile rigidity should be expected. A significant decrease of dorsal stresses can also be achieved by encouraging the surgeon to position the cylinders toward the lower part of the corpora. The numerical simulations indicate that circular cylinders may allow greater biomechanical compatibility of the IPP with the penis structure than elliptic ones, and this should be a subject for clinical investigations.

Biomechanical Phenomena↗

Legeais BioKpro III keratoprosthesis implantation: long term results in seven patients.

AIMS: The long term results of the Legeais BioKpro III keratoprosthesis are presented for seven patients with severe corneal scarring. METHODS: The study took place at Moorfields Eye Hospital, London. Patients had either end stage ocular surface disease or corneal opacification after multiple failed graft surgery, with the potential for significant visual improvement. After insertion the device was covered with a conjunctival flap or buccal mucous membrane graft, which was later opened to expose the optic. The outcome measures were vision, complications, and retention of the device. RESULTS: The BioKpro III was inserted into seven patients with severe corneal scarring: ocular cicatricial pemphigoid, measles keratitis, thermal injury, Stevens-Johnson syndrome, aniridia, chemical injury, and congenital rubella. The follow up was 18-48 months. The keratoprosthesis failed in six, because of extrusion occurring 2-28 months postoperatively. Retroprosthetic membranes occurred in three patients, and endophthalmitis in one. Vision improved from hand movements to 6/12 in the only patient who retained the KPro; however he was troubled by mucus accumulation on the optic. CONCLUSIONS: The one success has been in a patient with thermal burns. The remaining results have been poor, with the KPro extruding in six of the seven patients.

Adult↗

Clinical results of implantation of the Chirila keratoprosthesis in rabbits.

AIMS/BACKGROUND: An ideal keratoprosthesis (KPro) would closely resemble a donor corneal button in terms of its surgical handling, optics, and capacity to heal with host tissue in order to avoid many of the complications associated with the KPros which are currently in clinical use. This study was carried out to assess the long term clinical outcomes on implantation of the core and skirt poly(2-hydroxyethyl methacrylate) KPro in animals. METHODS: 20 KPros were made and implanted as full thickness corneal replacements into rabbits and followed for up to 21 months to date. RESULTS: 80% of the prostheses have been retained, with a low incidence of complications such as cataract, glaucoma, and retroprosthetic membrane formation which are frequently associated with KPro surgery. CONCLUSIONS: KPros of this type may offer promise in the treatment of patients for whom penetrating keratoplasty with donor material carries a poor prognosis. Refinement of the KPro and further animal trials, including implantation into abnormal corneas, are however mandatory before human implantation could be planned.

Animals↗

Complications of motility peg placement for porous hydroxyapatite orbital implants.

AIM: To evaluate the complications associated with pegging of porous hydroxyapatite orbital implants. METHODS: Complications associated with pegging were retrospectively reviewed from the charts of 100 of 133 patients with hydroxyapatite implantation from 1993 to 2000. RESULTS: 48 (48%) of the 100 hydroxyapatite implanted patients who had undergone pegging were found to have problems with their pegs, including discharge (45.8%), peg falling out (20.8%), pyogenic granulomas (16.7%), popping peg (14.6%), hydroxyapatite visible around peg hole (8.3%), part of peg shaft visible (6.2%), peg drilled off centre (6.2%), peg drilled at an angle (4.2%), and excess movement of peg (4.2%). The standard peg fell out statistically more often than the peg and sleeve system (Yates's corrected chi(2), p=0.038). There was a trend towards complications of the peg with use of a standard peg (versus sleeved peg) (p=0.226). CONCLUSIONS: There are several potential complications of pegging. Most complications are minor and can be managed successfully.

Adolescent↗

The CP stent--short, long, covered--for the treatment of aortic coarctation, stenosis of pulmonary arteries and caval veins, and Fontan anastomosis in children and adults: an evaluation of 60 stents in 53 patients.

OBJECTIVE: To evaluate the feasibility and usefulness of the Cheatham platinum (CP) stent in a broad spectrum of lesions. METHODS: Retrospective analysis of 60 implanted CP stents (11-80 mm lengths, 12 covered) between September 2001 and March 2004. PATIENTS: 53 patients aged 2.5-68 years (median 17 years). Body weight ranged from 12-95 kg (median 52 kg). Thirty six patients had aortic (re)coarctation; seven of them had functionally interrupted aortic arches. Thirteen patients had pulmonary artery stenosis and four had stenosis of caval veins or conduits in a total cavopulmonary connection (TCPC). RESULTS: Arterial pressure gradients dropped from 33 mm Hg (range 20-80 mm Hg) to 5 mm Hg (range 0-10 mm Hg) and pressure gradients in TCPC or caval veins dropped from 4 mm Hg (range 4-20 mm Hg) to 0 mm Hg (range 0-3 mm Hg). All stents were placed in the target lesion without complications. Three stent fractures without clinical instability were noted. CONCLUSIONS: The CP stent is suitable for the treatment of vessel stenosis in congenital heart diseases from childhood to adulthood. Whether these good results will be stable in the long term needs to be investigated.

Adolescent↗

A review of the complications and results of implantation of the AMS artificial urinary sphincter.

The history and evolution of devices designed to achieve urinary continence are reviewed. Passive and active (including volume and pressure regulated) devices are described in detail. Meta-analysis of the published studies revealed that continence improved in 88% of patients and total continence was achieved in 73%. Global revision rate was 32%. Urethral erosion occurred in approximately 12%, infection in 4.5% and mechanical complications in 14% of cases. The complications relating to the AMS artificial urinary sphincter are analyzed. The majority of patients (> 85%) required only one revision. 22% of complications were due to mechanical malfunction. Infection comprised 12.9% of complications. The patterns of total revisions followed a double exponential decay curve: 50% of revisions were performed within 8 months and 90% within 3 years of implantation. Complications were still reported several years postimplantation. This review analyzes the problems relating to the application of pressure and the presence of foreign material around the urethra and exemplifies the requirement for long-term specialist follow-up of these patients.

Animals↗

[Theoretical-mathematical models of the forces effected by allograft sling systems in incontinence therapy].

The various allograft sling systems are differentiated by their devices, the different pore sizes of the prolene bands as well as, importantly, the various anatomical sling positions. Retropubic slings are positioned through the Retzius space, transobturator slings are placed through the obturator foramen. One of the major risks of complications when inserting these slings is that of over-tightening. The forces exerted during the positioning and fine tuning of the mesh slings are explained by a mathematical model. The flatter the suburethral angle after the tape placement, the stronger a force is to be applied for a further tightening of the tape. Due to the effective strength vectors, there seems to be less chance of overcorrection with the transobturator approach.

Biomechanical Phenomena↗

Tissue response to an expanded polytetrafluoroethylene external valve support device: a histologic study in dogs.

Expanded polytetrafluoroethylene (ePTFE) external valve support devices (EVS) have been used successfully in patients to restore valve function in leg veins with incompetent valves when incompetence is due to dilatation of the vein walls or elongation of the valve leaflet edges. To assess tissue response to these devices, the authors implanted 12 of them in dogs, wrapping the devices around veins in the head and neck. The dogs recovered from the implantation procedure uneventfully, and the veins remained patent on color flow Doppler scanning. Gross and histologic evaluations of vein segments and attached EVS devices after sacrifice of the dogs 30 days postoperatively showed that the ePTFE devices did not affect vein patency or the cellular composition or architecture of vein walls. There were no adverse tissue reactions to the EVS and no thrombus formation in the veins to which the EVS had been applied. Tissue attachment to the EVS was apparent in all specimens. These histologic results support clinical experiences indicating that the ePTFE EVS device is safe to use in external valvuloplasty for the treatment of venous incompetence.

Animals↗