Installation requirements for an argon laser angioplasty system.
Explore the source record for details and available documents.
Angioplasty, Balloon↗
Biomedical subjects
W D Jeans
Publications and source records attributed to W D Jeans.
Assessment of angioplasty balloon catheters: further studies.
Eight millimetre diameter angioplasty balloon catheters of both the Gruntzig and Olbert types from five manufacturers have been tested in vitro to establish bursting pressures and the changes in maximum and deflated diameters following repeated inflations, both when free and within a restraining sleeve. Maximum inflated diameters were within 10% of that stated and all types of balloon except one burst at a pressure greater than the recommended value. Deflated diameters were approximately 1 mm greater than insertion diameters, which are much smaller in the Olbert type. All balloons became a little larger with each of the first few distensions, and became stiffer. The maximum diameter was reached and remained constant after 10-15 distensions. Distension within a latex sleeve did not change bursting pressures, and it is considered that results from unconstrained testing can be extrapolated to behaviour in vivo. Computer modelling and calculation of maximum stress resultants also showed that calculated longitudinal and circumferential stresses are unaffected by applied restrictions. It is concluded that balloon technology is steadily improving and it is suggested that British Standards should be established for dilatation balloon catheters. Amongst other factors these Standards should include maximum recommended inflation pressures that are at least 2 atm less than bursting pressures, whilst the stated maximum diameter should be for fully extended balloons, and should have a tolerance of more than +/- 10%.
Angioplasty, Balloon↗
Assessment of angioplasty balloon catheters: preliminary studies.
Gruntzig balloon catheters from three manufacturers have been tested in vitro to establish a method of assessing the diameters and bursting pressures of inflated balloons. The method of testing and of measuring the inflated balloons is described. It was found that there were considerable variations in the behaviour of different balloons, and the relevance of this to arterial rupture is discussed. There were significant associations between the manufacturer and premature rupture of the balloon (p less than 0.01), and between co-axial construction of the catheter and overdistension of the balloon by more than 20% (p less than 0.01). The balloon length and the stated maximum diameter were not associated with either premature failure or overdistension.
Angioplasty, Balloon↗
Computed tomography of the internal auditory canals.
Explore the source record for details and available documents.
Cerebellar Neoplasms↗
The place of percutaneous transluminal angioplasty in the treatment of patients having angiography for ischaemic disease of the lower limb.
A prospective survey was made during 1 year of all 226 patients having angiography for lower limb ischaemia, to assess the accuracy of selection for angiography and the current treatment of the disease. Sixty-two percent of the patients presented with intermittent claudication and were found to have a fall in ankle systolic blood pressure on exercise. Thirty-one percent had rest pain or ischaemic skin changes. All patients had abnormal angiograms, with aorto-iliac disease present in 42%, combined with distal disease in 22%. There was a normal aorto-iliac segment in 58% of patients who had more distal disease. Calf-vessels only were affected in 15%. Treatment was by surgery only in 49%, and balloon dilatation only in 19%. A further 2% had dilatation as a complement to surgery, and 6% had surgery when dilatation failed or had complications. Dilatation was attempted unsuccessfully in 6%. No treatment was offered to 20% of patients. It is concluded that selection of patients for angiography using clinical and vascular laboratory assessment avoids unnecessary examinations and that approximately one-third of these selected patients are candidates for angioplasty, which is the preferred first option for treatment in all suitable patients.
Adult↗
The role of balloon angioplasty in the management of lower limb ischaemia.
Three hundred and twenty-three angioplasties (159 iliac; 164 femoro-popliteal) were performed for lower limb ischaemia on 253 consecutive patients from 1980-86. The mean resting ankle/brachial pressure index (ABPI) was increased at one month in open angioplasties as follows: Femoro-popliteal 0.56-0.82; iliac with open superficial femoral artery (SFA) 0.7-0.95; iliac with occluded SFA 0.52-0.63. Successful angioplasty virtually abolished the post-exercise fall in ABPI except for patients having iliac dilations when multisegment disease was present. At 5 years, cumulative patency was 72% for iliac angioplasty and 53% for femoro-popliteal angioplasty. The results of angioplasty were compared with operative arterial reconstructions during 1985. Eighty-eight (91%) of 96 surgical bypasses were alive and patent at hospital discharge and 44 (71%) of 62 angioplasties were patent at 1 month. There were many fewer complications with angioplasty which involved a much shorter hospital stay (2 days vs 16 days).
Angioplasty, Balloon↗
Tubo-cornual polyps: their relevance in subfertility.
One-hundred-and-seventy-four patients having hysterosalpingographs during the investigation of infertility have been reviewed to assess the incidence of tubo-cornual polyps and their relation to subsequent pregnancy. Definite polyps were present in 31 (18%) of the patients. There was no significant difference in age or parity in women with and without polyps, nor in associated infertility factors such as tubal occlusion or oligospermia. None of the patients with polyps had endometriosis. Conception rates in the two groups were not significantly different. The cumulative rates at 18 months with and without polyps were 34.5 +/- 13.7% (SE) and 43.6% +/- 3.9% respectively in the overall groups, and 36.9% +/- 24.1% and 59.0% +/- 9.1% in the couples with otherwise unexplained infertility. It is concluded that tubo-cornual polyps are not related to infertility and that they should not be treated.
Adult↗
The accuracy of digital subtraction angiography for the quantification of atherosclerosis.
Digital subtraction angiography (DSA) allows the degree of arterial patency or stenosis to be rapidly quantified. We have assessed the accuracy with which a single-plane DSA system is able to quantify area patency by densitometric and geometric methods. Arterial phantoms were designed to test for systematic error; intra-arterial DSA images of critical lesions of the carotid bifurcation and the lower abdominal and peripheral vessels were used to determine intra- and interobserver reproducibility. The densitometric method, which was more accurate than the geometric method, had a mean systematic error of up to 4% and a mean intra-observer variability of about 15% (coefficient of variation). We have identified the principal sources of inaccuracy and ways in which it may be reduced.
Arteriosclerosis↗
Moyamoya disease: an unusual cause of cerebral infarction.
A South African Bantu patient presenting with recurrent strokes and a change in personality was found to have cerebral infarction due to moyamoya disease. The disease has a characteristic radiological pattern of narrowing or occlusion of the distal internal carotid arteries associated with a profuse vascular network at the base of the brain and in the basal ganglia: the moyamoya vessels. The clinical features and the collateral vascular pathways that may develop after cerebral vascular occlusion are discussed and the surgical options for increasing cerebral blood flow described. In this patient a development of the technique in which the superficial temporal artery is laid onto the brain without interruption of the donor vessel was used, with improvement in the clinical picture.
Adult↗
Angiography in transient cerebral ischaemia using three views of the carotid bifurcation.
A prospective study was made of 135 patients having cerebral angiography for suspected carotid atheroma. The aim was to assess the value of a technique in which selective injections were used to show the origins of the vessels from the aortic arch and three views were taken of each of the carotid bifurcations. Disease was frequently asymmetrical and was shown in only one of the three views of the carotid bifurcation in 44% of 181 patent atheromatous internal carotid arteries. Atheroma was seen on a single view significantly more often (p less than 0.01) than was complicated atheroma, indicating that the technique was showing more early lesions than would be seen with fewer views of the region. Disease was not shown significantly more often in any one particular view, so that all three are essential to examine the bifurcation completely.
Adult↗
A comparison of the costs of vascular surgery and balloon dilatation in lower limb ischaemic disease.
The length of stay in hospital was recorded for 24 patients admitted for investigation and treatment of vascular disease of the lower limb and a detailed analysis of the costs incurred was made for 10 patients. It was found that the mean cost of angiography and surgery was pounds 1577 and of angiography and dilatation, pounds 301. The major factor in the cost difference was the shorter hospital stay for dilatation, with lesser factors being the use of fewer staff and the avoidance of general anaesthesia.
Angiography↗
The effects of introducing balloon dilatation into vascular surgical practice.
The numbers of angiograms, balloon dilatations, reconstructive operations and amputations carried out annually over a 5-year period following the introduction of balloon dilatation have been counted and the change in estimated costs calculated. Over the 5-year period the numbers of angiograms and reconstructive operations carried out have doubled and the number of amputations has fallen from 52 in the first year to 39 in the fifth year. The number of dilatations has increased from six in five patients in the first year to 97 in 75 patients in the fifth year. The cost of investigation and treatment has doubled but since more patients are being treated effectively, the mean cost per patient treated has fallen from pounds 1855 to pounds 1277. The introduction of balloon dilatation into vascular practice causes patients to be investigated earlier in the progress of their disease and enables more patients to be treated effectively with greater cost-efficiency, but does not reduce the overall cost of investigation and treatment of ischaemic disease of the lower limb.
Angiography↗
[Angioplasty in primary Budd-Chiari syndrome. Apropos of 3 cases].
Three patients with the primary Budd-Chiari syndrome were treated by percutaneous transluminal angioplasty. Results showed an apparent poor response to angioplasty of irregular stenoses of the suprahepatic vessels and a good response when stenosis was due to membrane, but recurrence of the latter lesion after several months. The transient efficacy of this procedure in cases with a suprahepatic or caval membrane suggests that it be used pre-operatively for this indication.
Adult↗
Systematic tutorials in radiology for clinical medical students.
The aims and objectives of radiological teaching to clinical medical students at one teaching hospital are defined and the methods of achieving these using systematic small group tutorials are described. The objectives of the course are to enable a newly qualified doctor to request radiological investigations sensibly and to interpret common abnormalities. The 34 tutorials given are designed to cover common radiological appearances and are related to the clinical firm or team to which the student is attached. It is concluded that the function of teaching is to stimulate learning and that systematic tutorials provide an organised framework within which the student can correlate the information gained from several sources.
Education, Medical, Undergraduate↗
Is soft tissue radiology useful in acromegaly?
Twenty-six acromegalics had measurements of serum growth hormone (GH) levels during a glucose tolerance test, X rays of the heel for heel pad thickness, and of the hand for bone/soft tissue ratio. These measurements were performed before and between 2 and 7 years after treatment, which was by transethmoidal hypophysectomy, external irradiation or a combination of the two. Neither the heel pad thickness nor bone/soft tissue ratio correlated with the mean serum GH nor with each other before and after treatment. The nine patients who were assessed as showing a good clinical response to treatment showed a significantly greater fall in mean serum GH than the 17 patients who were assessed as unchanged or partial responders (40.1 +/- 20 mmu/l compared with 9.9 +/- 14.0 mmu/l, p = 0.02). However, there were no significant differences in changes of heel pad thickness nor bone/soft tissue ratio between these groups. It is concluded that these radiological measurements of soft tissues are unhelpful in the follow-up of acromegalic patients.
Acromegaly↗
Dieulafoy's disease: a distinctive arteriovenous malformation causing massive gastric haemorrhage.
Dieulafoy's disease is a distinctive arteriovenous malformation of the gastric fundus, which presents with massive or recurrent gastrointestinal bleeding. The lesion is very small and easily overlooked even at laparotomy, and can only be correctly diagnosed by endoscopy or arteriography if the patient is actively bleeding. A wedge resection will stop bleeding and give histological confirmation of the characteristic submucosal vessels.
Adult↗
Percutaneous transluminal angioplasty for lower limb ischaemia.
Forty successful percutaneous transluminal angioplasties (PTA) were performed in the iliac and femoropopliteal segments of 33 patients with lower limb ischaemia. There was immediate symptomatic relief in 37 limbs (92 per cent) although 7 relapsed and 5 patients required reconstructive arterial surgery within a month of PTA. Objective testing showed that the longer term relapse rate (median follow-up 12 months) was low (10 per cent). Despite a significant incidence of early complications and relapse, PTA provided a good long term result in the majority of patients treated.
Adult↗