Biomedical subjects

B M Stanley

Publications and source records attributed to B M Stanley.

3 recordsLinked to original sources

PubMed2001

Fenestration in endovascular grafts for aortic aneurysm repair: new horizons for preserving blood flow in branch vessels.

PURPOSE: To describe techniques for deploying fenestrated stent-grafts that use partial graft deployment and guided tracking of the fenestration to the arterial orifice. TECHNIQUE: Fenestrations have been added to custom-made tube grafts and commercially manufactured Zenith stent-graft systems to preserve perfusion of aortic side branches. Partial device deployment, orientation markers on the endograft, and intraoperative angiography enable maneuvering of the fenestration over the orifice of the target vessel with the aid of guiding catheters. Placement of a Palmaz stent overlapping the fenestration and vessel orifice secures the junction. Two variations of fenestration have preserved blood flow in renal arteries during endovascular repair of abdominal aortic aneurysms (AAAs); similar techniques have maintained flow to the celiac axis in a thoracic aortic aneurysm. CONCLUSIONS: Accurate placement of a fenestration over the orifice of a target vessel is feasible, but long-term maintenance of position is dependent on secure graft fixation. This capability brings us a step closer to overcoming the problem of inadequate necks in infra-renal AAAs, especially when the neck is foreshortened by asymmetry of the renal origins. It may also pave the way for the eventual replacement of the entire aorta with an endoluminal graft.

Aged↗

PubMed2001

Evaluation of patient selection guidelines for endoluminal AAA repair with the Zenith Stent-Graft: the Australasian experience.

PURPOSE: To review the patient selection guidelines for endovascular repair of abdominal aortic aneurysms (AAA) using the Zenith Endovascular Graft and establish an order of importance for each criterion. METHODS: The Zenith Endovascular Graft Research Database was interrogated for information on 238 patients (209 men; mean age 74.9 +/- 0.9 years, range 50-94) treated with a Zenith bifurcated graft from 1994 to 1998. The common complications of endoluminal AAA repair (endoleak, migration, graft occlusion, graft kinking, conversion, and deployment failure) were analyzed to determine any associations with selection criteria. RESULTS: By 1998, 69% of endograft patients did not meet the recommended guidelines; however, primary and secondary aneurysm exclusion rates were 87% and 94%, respectively. Over a median follow-up of 13.4 months (interquartile range 2.8-24.0), 38 (16%) patients developed 28 (74%) early and 10 (26%) late type-I endoleaks. The endoleak rate in necks < or = 10 mm long was 57% (8/14). Endoleak was associated with a neck contour change >3 mm (p = 0.003) and neck length <20 mm (p = 0.045). The risk of proximal endoleak was 4 times greater if at least one of the proximal neck guidelines was breached; combined guideline deviations of "contour change and large diameter" (p = 0.0004), "contour change and short length" (p = 0.006), "large diameter and short length" (p = 0.01), and "contour change and angle" (p = 0.03) also increased the risk of endoleak. Endograft migration was seen in 10 (4.2%) cases; only neck diameter >28 mm (p = 0.0024) was associated with this complication. CONCLUSIONS: Proximal neck contour, length, and diameter are the most important criteria in terms of endoleak development. Breaching the proximal neck length criterion resulted in a 4-fold increase in endoleak, and combined deviations from the guidelines multiplied the effect. Necks < or = 10 mm long are unsuitable for the standard Zenith graft.

Aged↗

PubMed1998

Informed consent: how much information is enough?

BACKGROUND: Recent judicial decisions involving informed consent have led to some medical practitioners altering the way they obtain consent. The aim of this study was to determine the degree to which patients understood the risks associated with a surgical procedure after giving routine consent and whether providing additional detailed verbal and/or written information improved their understanding. It was further determined whether the provision of more extensive information altered patients' anxiety levels. METHODS: Patients undergoing femoral popliteal bypass or carotid surgery were randomized to obtain either routine consent only or routine consent with verbal or written or verbal and written consent. Patients undertook a pre-operative risk and complication questionnaire, a pre- and postoperative anxiety and depression evaluation and a follow-up questionnaire 6 weeks after discharge. RESULTS: Thirty-two patients were included in the trial. The comprehension questionnaire resulted in a correct percentage response of 48% for the routine information only, 59% with added verbal information, 59% with added written information and 55% with added written and verbal information. Twenty-five per cent of patients stated that they had a poor understanding of the risks and complications of the procedure. CONCLUSIONS: Additional written or verbal information did not improve a patient's understanding of risks and complications of the procedure. It also did not improve patients' perceived understanding of the operation or its complications. Patients' anxiety levels were unaltered by the increase in the information they were given. The information provided to patients should be simple, easy to understand and list any possible major complications to enable the patient to determine whether to undergo or decline a procedure.

Adaptation, Psychological↗