Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Prosthesis Coloring”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 1,099 records · Page 61Linked to original sources
PubMed1985

Ceramometal crowns and bridges. Focus on failures.

There are numerous factors that can have an adverse or beneficial effect upon the esthetic appearance of a ceramometal restoration. Some of these factors are beyond the influence of the dentist unless he or she is aware of them. As knowledgable practicing dentists, they have the ability to prescribe for their patients in such a manner as to achieve greater success and, in turn, greater patient acceptance and recognition. These are the rewards of a successful crown and bridge practice, and the ceramometal restoration is the basic state of the art prosthesis in present use. Knowing how to take a shade under the proper lighting conditions is generally well taught as part of the dental school curriculum, but the knowledge that shade guides are manufactured with built in idiosyncrasies of color variations from guide to guide is an enlightening experience. O'Brien of the Department of Dental Materials at the University of Michigan School of Dentistry clearly demonstrated the variabilities of color intensities between porcelain manufacturers. Laboratory technicians have been frustrated by the inconsistency of shades of porcelains from one lot number to another. It is now more fully understood that fluorescence is an important factor in patient satisfaction, as patients observe and have their restorations seen under differing lighting conditions. The type of alloy used in the ceramometal combination can have an effect upon the esthetic result. The wider use of silver-palladium alloys requires that the porcelain employed be of a nongreening nature, or else the final glazed prosthesis will give off a greenish cast. The ability of the opaque to block out the metal substructure while blending with the gingival and incisal shades eliminates the graying out, which can be esthetically objectionable to the patient. However, one of the most important considerations in aesthetic ceramometal restorations is the correct anatomy, placement, and harmonious blending with the oral and facial features and coloring of the patient. It would be comforting if we could all agree on a definition of esthetics. There is perhaps no more important aspect of marketing the ceramometal restoration to the patient than arrive, in advance, on a common ground and understanding of what the esthetic goals of the case are in realistic terms.(ABSTRACT TRUNCATED AT 400 WORDS)

Chemical Phenomena↗
PubMed2003

Efficacy of ultrasound scan contrast agents in the noninvasive follow-up of aortic stent grafts.

OBJECTIVE: Computed tomographic angiography (CTA) is currently the most commonly used technique for postoperative surveillance to detect endoleaks after endovascular stent graft repair of abdominal aortic aneurysms. We have evaluated the efficacy of duplex ultrasound scan with the addition of an ultrasound scan contrast agent in documenting endoleaks and compared these results with CTA. METHODS: Conventional duplex ultrasound scan with color Doppler imaging (CDI) was first done as part of routine postoperative surveillance. After the CDI study, a 1-mL bolus of ultrasound scan contrast was given via an antecubital vein, followed by a 5-mL flush with normal saline solution. The duplex ultrasound scan evaluation of the stent graft was repeated once the contrast agent was circulating throughout the blood pool, with tissue harmonic imaging to optimize visualization of the contrast agent. Status of the stent graft, the presence or absence of any endoleak, and whether these endoleaks were graft related (group I) or arterial branch related (group II) were recorded. Findings were compared with CTA studies done within a 2-week period of the ultrasound scan examination. RESULTS: Twenty patients were evaluated, 18 with modular stent grafts and two with unibody bifurcated stent grafts. Patients had a mean age of 74.5 +/- 7.6 years; 19 were male, with only one female. All stent grafts remained widely patent with normal aortoiliac flow hemodynamics. Duplex ultrasound scan with contrast identified all eight of the endoleaks seen with CTA and was able to determine whether they were group I or group II leaks. In two patients, ultrasound scan with contrast detected small endoleaks at the proximal graft attachment site, with extravasation of contrast into the aneurysm sac during systole. These endoleaks were not seen with CTA but were confirmed with conventional angiography at the time of endovascular closure. Standard duplex ultrasound scan with CDI failed to identify four of the 10 endoleaks in patients with technically difficult conditions. CONCLUSION: Duplex ultrasound scan, when used with an intravenously administered ultrasound scan contrast agent in the noninvasive follow-up of patients with aortic stent grafts, appears to provide good sensitivity to the presence and type of endoleaks, even in patients with technically difficult conditions not amenable to conventional duplex ultrasound scan with CDI.

Aged↗
PubMed2006

Contrast-enhanced Duplex surveillance after endovascular abdominal aortic aneurysm repair: improved efficacy using a continuous infusion technique.

INTRODUCTION: Currently, postoperative endoleak surveillance after endovascular aortic aneurysm repair (EVAR) is primarily done by computed tomography (CT). The purpose of this study was to determine the efficacy of contrast-enhanced ultrasonography scans to detect endoleaks by using a novel infusion method and compare these findings with those of CT angiography (CTA). METHODS: Twenty male patients (mean age, 70.4 years) underwent surveillance utilizing both CTA and contrast-enhanced color Duplex imaging. One 3-mL vial of Optison (Perfluten Protein A microspheres for injection) and 57 mL normal saline, for a total of 60 mL, were administered to each patient as a continuous infusion at 4 mL/min via a peripheral vein. Each study was optimized with harmonic imaging, and a reduced mechanical index of 0.4 to 0.5, compression of 1 to 3, and a focal zone below the aorta to minimize microsphere rupture. One minute was allowed from the time of infusion to the appearance of contrast in the endograft. Flow was evaluated within the lumen of the graft and its components, as was the presence or absence of endoleaks. Findings were compared with standard color-flow Duplex imaging and CT utilizing CTA reconstruction protocols. RESULTS: All patients evaluated had modular endografts implanted for elective aneurysm repair. Contrast-enhanced duplex scans identified nine endoleaks: one type I and eight type II. No additional endoleaks were seen on CTA. However, CTA failed to recognize three type II endoleaks seen by contrast-enhanced ultrasound. The continuous infusion method allowed for longer and more detailed imaging. An average of 46.8 mL of the contrast infusion solution was used per patient. CONCLUSIONS: Contrast enhanced Duplex ultrasonography accurately demonstrates endoleaks after EVAR and may be considered as a primary surveillance modality. Continuous infusion permits longer imaging time.

Aged↗
PubMed1998

Pseudoabscess of the aortic root caused by ectopic seating of an aortic prosthesis.

An approach to some of the technical problems involved in aortic valve replacement includes positioning of some or all of the prosthetic ring in a position ectopic to the true aortic annulus. Such placement can create the apparent appearance of an echolucent region adjacent to the prosthetic ring that shows flow on color Doppler interrogation to suggest the presence of an abscess cavity. This case demonstrates how such a pseudoabscess can be created and the clinical and echocardiographic clues that were used to make the correct diagnosis.

Abscess↗
PubMed1997

Circulating microemboli in patients after aortic valve replacement with pulmonary autografts and mechanical valve prostheses.

BACKGROUND: The pulmonary autograft procedure (Ross) is now considered the gold standard for aortic valve replacement. One of its advantages is the freedom from macroemboli without anticoagulation. Whether this holds true for circulating microemboli, detectable as high-intensity transient Doppler signals (HITS), has not yet been verified. METHODS AND RESULTS: We investigated 8 patients (2 women, 6 men; mean age, 50.6+/-17.9 years) after the Ross procedure, 9 patients (3 women, 6 men; mean age, 67.2+/-9.46 years) after aortic valve replacement with a mechanical valve prosthesis, and 12 young healthy volunteers by unilateral 1-hour recording of the middle cerebral artery on digital audio tape. Patients with extracranial carotid artery disease were excluded by color duplex sonography. During the off-line evaluation, the investigator was not aware of any patient details. No HITS were detected in healthy volunteers (95% confidence interval [CI], 0% to 26.46%). After the Ross procedure, 1 patient had 11 and 1 patient had 1 HITS (95% CI, 3.19% to 65.09%). All recipients of mechanical valves had HITS, ranging from 2 to 84 per hour (95% CI, 66.7% to 100%). Significantly more recipients of mechanical valves exhibited HITS than recipients of pulmonary autografts (P<.05) or control subjects (P<.05). CONCLUSIONS: In contrast to mechanical valves, pulmonary autografts are seldom the source of microemboli, confirming the pulmonary autograft as the superior substitute for aortic valve replacement.

Adult↗
PubMed1987

In vitro color flow, pulsed and continuous wave Doppler ultrasound masking of flow by prosthetic valves.

On the hypothesis that Doppler ultrasound fails to penetrate prosthetic valves, an in vitro flow simulation system was constructed in a large water tank. Conventional pulsed, continuous wave and Doppler color flow systems were used to detect flow in tubing placed diagonally within the water and maintained by a continuous pump. After control periods of flow detection within the tubing, six different prosthetic valves were interposed on a stage between the transducer and the tubing. In comparison with control measurements, detection of flow within the tubing was impossible when the Doppler beam traversed the central occluding ball of the Starr-Edwards Silastic prosthesis by any modality. Marked reduction in the detection of the Doppler signal was noted for the Starr-Edwards stellite prosthesis with only slight improvement in the ability to detect the flow signals through the central occluding discs of the Björk-Shiley, Hall-Kastor and St. Jude valves. In distinction to the other valves, the ability of Doppler ultrasound to detect flow behind the cusps of the Carpentier-Edwards heterograft was similar to that during the control period. An understanding of flow masking should improve the clinical utility of Doppler methods for investigating prosthetic valve dysfunction.

Color↗
PubMed1996

Iatrogenic rupture of internal carotid artery aneurysm. A complication of CT-guided needle biopsy of the neck.

Incidental rupture of an internal carotid artery aneurysm complicating a CT-guided needle biopsy of the neck is reported. A contrast CT scan failed to diagnose the lesion, which was not pulsatile and thought to be a neoplastic cervical lymph node. After leakage of the aneurysm. Color-Doppler scan and MRI identified aneurysmal changes of the carotid artery wall with an intraluminal thrombus. Successful emergency resection with a PTFE interposition graft was performed.

Aged↗
PubMed1995

[Color-coded duplex ultrasound as a screening method in trauma surgery].

Deep vein thrombosis with consecutive pulmonary embolism is one of the most important complications for trauma patients. At the University Hospital of Mainz, Department of Traumatology, colour duplex ultrasound is used as screening method in trauma patients. Fractures of thoracic and lumbal spinal bones, pelvis, hip and lower extremities, endoprosthesis of hip and knee joints and longer immobilisation are considered as special risk for the genesis of deep vein thrombosis. Out of 326 patients investigated with colour duplex ultrasound, 24 patients suffered from unknown deep vein thrombosis, 8 developing pulmonary embolism. We recommend colour duplex sonography on day 10, after the third week, and after longer immobilisation. Colour duplex sonography provides an easy performable and noninvasive method for screening evaluation of deep vein thrombosis in trauma patients.

Adolescent↗
PubMed1994

In vitro fluid dynamic evaluation of the Carbomedics bileaflet heart valve prosthesis in the aortic and mitral positions.

Since the introduction of bileaflet heart valve prostheses their clinical use has continued to escalate. The first of this valve type was the Standard St. Jude Medical (SSJM) prosthetic heart valve in 1977. The Carbomedics prosthetic heart valve (CPHV), introduced in the late 1980s, was intended to improve on the design of the SSJM bileaflet valve. The design changes in the CPHV valve, relative to the SSJM valve, may have the potential to affect its flow fields. This study, using flow visualization laser Doppler velocity measurements and color Doppler flow mapping, was intended to evaluate how these changes affect the flow fields in the near vicinity of the CPHV valve. The study was conducted in an in vitro pulse duplicator system. In the flow visualization study, the flow fields observed with the CPHV valve were quantitatively similar to those seen with the SSJM valve. Centralized jet-like flows with flow separation/stagnation were observed in the illuminated planes. The jet-like flows from the two lateral orifices were broader than that observed from the central orifice for both the CPHV and the SSJM valves. This fact implied that the major part of the volumetric flow was through the two lateral orifices, rather than the central orifice. In the laser Doppler velocity measurements, it was found that the flow field downstream of the SSJM valve was slightly more evenly distributed than that with the CPHV valve. In addition, the extent of the flow separation regions with the CPHV valve were slightly larger than with the SSJM valve. The slight differences in velocity profiles between the SSJM and the CPHV valves were due to the differences in leaflet opening angle. However, the levels of flow turbulence with the CPHV and the SSJM valves were found to be of the same order of magnitude. The results of the flow visualization and LDA velocity and turbulence measurements obtained in the study indicate that the differences in flow fields in the immediate vicinity of the CPHV valve relative to the SSJM valve are insignificant.

Aortic Valve↗
PubMedDate not supplied

Surgical repair of a post-traumatic arteriovenous fistula complicated by stent-graft misplacement.

An arteriovenous fistula (AVF) is an abnormal connection between an artery and a vein which may result from a traumatic injury or occur as a congenital abnormality. It may be asymptomatic or may present with a variety of symptoms. Surgical or endovascular treatment can be preferred. We present a case of unsuccessful percutaneous treatment of a femoral AVF due to misplacement of the stent-grafts, necessitating surgical correction.

Adult↗
PubMedDate not supplied

Traumatic axillary artery dissection with radial artery embolism.

This report describes a case of pathologically proven traumatic arterial dissection, presenting as complete occlusion of the axillary artery with radial artery embolism. Occlusion of the axillary artery by traumatic dissection mimicked transection and radial artery embolism mimicked congenital absence of the radial artery on the initial angiogram, but these were correctly diagnosed with the following sonogram.

Accidents, Occupational↗
PubMed2004

Survival after simultaneous left ventricular free wall, papillary muscle, and ventricular septal rupture.

Cardiac rupture is a catastrophic complication of acute myocardial infarction. The three potential sites of rupture are the left ventricular free wall, interventricular septum, and papillary muscle. Without rapid surgical correction, each of these complications typically leads to cardiogenic shock, multiorgan failure, and death. Postmortem analysis has identified a small number of cases in which myocardial infarction led to rupture at more than one of these sites; however, there are no reports of survival from such an event. We report a case involving rupture at all three sites in the same patient, emphasizing the importance of transesophageal echocardiography and surgical management.

Aged↗
PubMed2004

Coronary artery to the left atrial fistula after resection of atrial appendages.

We report the case of a fistula formation between the left circumflex coronary artery draining into the left atrium as a complication of radiofrequency cardio-ablation and resection of the atrial appendages. This complication was diagnosed with the use of transesophageal echocardiography and was subsequently confirmed on coronary angiography.

Aortic Valve↗
PubMed2006

T-banding: a technique for flow reduction of a hyperfunctioning arteriovenous fistula.

A common procedure for hyperfunctioning arteriovenous fistulas is banding, baring the potential for complications such as pre- and poststenotic dilatations and recurrence of high flow caused by slipping of the band itself. We describe a new technique that ensures proper fixation of the graft to prevent anastomotic aneurysms and enlarge the length of stenosis of the shunt vein in order to amplify the effect of flow reduction. This technique was used in 22 patients, with a mean flow reduction of about 50%. The procedure was effective and safe at 1 to 3 months follow-up.

Aged↗
PubMed1997

Echocardiographic recognition of iatrogenic aortic valve leaflet perforation.

BACKGROUND: There is a paucity of literature regarding iatrogenic aortic valve perforation after cardiac operations performed in the vicinity of the aortic valve. This report describes the echocardiographic recognition of iatrogenic aortic valve perforation. METHODS: Among 6 patients who had previously under-gone non-aortic valve cardiac operations, a diagnosis of iatrogenic aortic regurgitation was made by transthoracic two-dimensional echocardiography and Doppler color flow imaging. RESULTS: The location of the aortic valve leaflet perforation varied and depended on the site of the previous intracardiac lesion repair. Repeat operations in 5 patients confirmed the echocardiographic findings. Aortic valve repair was confirmed in 2 patients by transesophageal echocardiography, whereas aortic valve replacement became necessary in 2 other patients. A fifth patient with acquired cardiomyopathy underwent orthotopic heart transplantation. CONCLUSIONS: A detailed two-dimensional echocardiographic examination, along with color flow imaging, should be done to evaluate iatrogenic aortic valve perforation in patients with a new murmur of aortic regurgitation after cardiac operations in proximity to the aortic valve. Precise preoperative diagnosis of this lesion allows optimal surgical planning and treatment.

Adult↗
PubMed1998

The outcome and indications of the Cox maze III procedure for chronic atrial fibrillation with mitral valve disease.

OBJECTIVE: The efficacy of the Cox maze III procedure for chronic atrial fibrillation associated with mitral valve disease is unclear, and so was evaluated in this study. METHODS: In 30 patients, we applied the maze III procedure (cut and suture), except for one modification in the case of a left posterior sinus node artery. After dividing the patients into sinus rhythm and atrial fibrillation groups more than 6 months after the operation, we compared various parameters. RESULTS: Sinus rhythm was restored in 27 patients (90%). One patient had atrioventricular reentrant tachycardia and needed a pacemaker for sick sinus syndrome (3.3%). The f-wave voltage in lead V1, the preoperative cardiothoracic ratio, the preoperative left atrial systolic dimension, and the duration of atrial fibrillation were 0.23 +/- 0.10 mV, 60.4% +/- 5.2%, 57.4 +/- 8.2 mm, respectively, and 5.1 +/- 4.6 years in the group with sinus rhythm, and were 0.06 +/- 0.05 mV, 77.7% +/- 10.3%, 95.3 +/- 24.0 mm, respectively, and 11.8 +/- 5.5 years in the group with atrial fibrillation. These parameters were all significantly different between the groups. Regarding atrial function, a transmitral flow A wave was detected in 66.7% and a transtricuspid flow A wave in 100%. Only the duration of atrial fibrillation had a significant influence on the restoration of left atrial function. CONCLUSION: The maze III procedure was effective for atrial fibrillation associated with mitral valve disease. This procedure should be applied to patients with a cardiothoracic ratio less than 70% and a left atrial systolic dimension less than 80 mm.

Adult↗