IEC standards for radiological equipment: issues for the industry and for end users.

The International Electrotechnical Commission (IEC) is a global standard organisation established under the Presidency of Lord Kelvin in 1906. All medical equipment standards in IEC are dealt with by Technical Committee (TC) 62, and within this, Medical Imaging Equipment Standards are developed under the guidance of Subcommittee (SC) 62B. In September 2005, a special meeting of a Steering Group of IEC SC 62B was held to review X-ray standards and to identify an approach to new standards in this field. The agenda for new standards arising from this was definitively established and consolidated, concentrating on whole systems, with the aspiration of returning later to acceptance test and QA standards. A liaison was also established between SC 62B and SENTINEL. In addition, it was decided to review SC 62B's liaisons with the International Atomic Energy Agency and International Commission on Radiological Protection and some national/international professional bodies.

Human embryonic stem cell-derived cells rescue visual function in dystrophic RCS rats.

Embryonic stem cells promise to provide a well-characterized and reproducible source of replacement tissue for human clinical studies. An early potential application of this technology is the use of retinal pigment epithelium (RPE) for the treatment of retinal degenerative diseases such as macular degeneration. Here we show the reproducible generation of RPE (67 passageable cultures established from 18 different hES cell lines); batches of RPE derived from NIH-approved hES cells (H9) were tested and shown capable of extensive photoreceptor rescue in an animal model of retinal disease, the Royal College of Surgeons (RCS) rat, in which photoreceptor loss is caused by a defect in the adjacent retinal pigment epithelium. Improvement in visual performance was 100% over untreated controls (spatial acuity was approximately 70% that of normal nondystrophic rats) without evidence of untoward pathology. The use of somatic cell nuclear transfer (SCNT) and/or the creation of banks of reduced complexity human leucocyte antigen (HLA) hES-RPE lines could minimize or eliminate the need for immunosuppressive drugs and/or immunomodulatory protocols.

[Off-pump coronary artery bypass: analysis of 1080 patients]. / Le pontage coronaire à coeur battant: à propos de 1080 patients.

A consecutive cohort including 1080 patients undergoing "off-pump" myocardial revascularization was reviewed. An average of 2.22 bypass/patients was performed. The death-rate during the first 30 days after surgery was 0.65%. Four cases needed cross-over to on-pump. The postoperative events were: need of inotropic drugs (2.7%), atrial fibrillation (12.4%), myocardial infarction (6.6%). The extubation was performed before the first postoperative 24 h in 91.9% of cases. The majority of patients was discharged from hospital before 8 days after surgery. Off pump coronary artery bypass surgery exhibit good results for most of the patients even if they present multiple vessel disease and high operating risk.

The 79,370-bp conjugative plasmid pB4 consists of an IncP-1beta backbone loaded with a chromate resistance transposon, the strA-strB streptomycin resistance gene pair, the oxacillinase gene bla(NPS-1), and a tripartite antibiotic efflux system of the resistance-nodulation-division family.

Plasmid pB4 is a conjugative antibiotic resistance plasmid, originally isolated from a microbial community growing in activated sludge, by means of an exogenous isolation method with Pseudomonas sp. B13 as recipient. We have determined the complete nucleotide sequence of pB4. The plasmid is 79,370 bp long and contains at least 81 complete coding regions. A suite of coding regions predicted to be involved in plasmid replication, plasmid maintenance, and conjugative transfer revealed significant similarity to the IncP-1beta backbone of R751. Four resistance gene regions comprising mobile genetic elements are inserted in the IncP-1beta backbone of pB4. The modular 'gene load' of pB4 includes (1) the novel transposon Tn 5719 containing genes characteristic of chromate resistance determinants, (2) the transposon Tn 5393c carrying the widespread streptomycin resistance gene pair strA-strB, (3) the beta-lactam antibiotic resistance gene bla(NPS-1) flanked by highly conserved sequences characteristic of integrons, and (4) a tripartite antibiotic resistance determinant comprising an efflux protein of the resistance-nodulation-division (RND) family, a periplasmic membrane fusion protein (MFP), and an outer membrane factor (OMF). The components of the RND-MFP-OMF efflux system showed the highest similarity to the products of the mexCD-oprJ determinant from the Pseudomonas aeruginosa chromosome. Functional analysis of the cloned resistance region from pB4 in Pseudomonas sp. B13 indicated that the RND-MFP-OMF efflux system conferred high-level resistance to erythromycin and roxithromycin resistance on the host strain. This is the first example of an RND-MFP-OMF-type antibiotic resistance determinant to be found in a plasmid genome. The global genetic organization of pB4 implies that its gene load might be disseminated between bacteria in different habitats by the combined action of the conjugation apparatus and the mobility of its component elements.

[Off-pump beating heart coronary artery bypass. Technical points of view and surgical results]. / Pontage coronaire à coeur battant. Aspects techniques et résultats hospitaliers.

A consecutive series of 746 patients undergoing heart beating myocardial revascularization was reviewed. An average of 2.30 grafts/patients was performed. The rate of mortality in the first 30 postoperative days was 0.28%. Two cases had to be terminated on-pump. We used the inotropic drugs in 0.6% of cases. The postoperative events were: atrial fibrillation (12.6%), myocardial infarction (0.3%). The rate of transfusion was 7.4%. The extubation was performed in the first 24 h postoperatively in 94.7% of cases. The majority of patients (91.3%) left the hospital in the first 8 d postoperatively. Off pump coronary artery bypass grafting gives good result for the most of the patients even for those with multiple vessel disease and high operating risk.

Recombinant hirudin anticoagulation for aortic valve replacement in heparin-induced thrombocytopenia.

PURPOSE: To report the case of a patient with HIT that received a prolonged infusion of r-hirudin (lepirudin; Refludan; Hoechst, France) before, during and after cardiopulmonary bypass (CPB) for aortic surgery. Although administration of r-hirudin for CPB anticoagulation has previously been reported, many questions persist concerning the best therapeutic regimen for CPB anticoagulation as well as the time of onset and the doses for postoperative anticoagulation. CLINICAL FEATURES: A 65-yr-old man was admitted for surgery of aortic stenosis after an episode of acute pulmonary edema complicated by deep venous thrombosis in the context of documented HIT. The patient received r-hirudin for 13 dy before surgery at doses (0.4 mg x kg(-1) bolus followed by 0.15 mg x kg(-1) x hr(-1) continuous infusion) that maintained activated partial thromboplastin time (aPTT) ratios between 2 and 2.5. Anticoagulation for CPB was performed with r-hirudin given as 0.1 mg x kg(-1) i.v. bolus and 0.2 mg kg(-1) in the CPB priming volume. Anticoagulation during CPB was monitored with the whole blood activated coagulation time and ecarin clotting time (ECT) performed in the operating room with values corresponding to r-hirudin concentrations >5 microg x ml(-1) during CPB. Anticoagulation during CPB was uneventful. Two bleeding episodes, related to the r-hirudin regimen and necessitating allogeneic blood transfusion, occurred after surgery. CONCLUSION: This case report confirms previous experience of the use of r-hirudin for anticoagulation during CPB and provides additional information in the context of prolonged r-hirudin infusion before and after CPB.

[Angioplasty or surgery in the patient with multivessel disease]. / Angioplastie ou chirurgie chez le patient pluritronculaire.

The aims of myocardial revascularisation are to treat angina, reduce ischaemia and improve life expectancy. Patients with multivessel disease have a poor prognosis, especially when the lesions are proximal, when the preseptal left anterior descending artery is involved and when left ventricular dysfunction is present. In this particular group of patients, coronary bypass surgery has been shown to improve 10 year survival. Coronary angioplasty has been compared with surgical treatment in many clinical trials. The medium-term survival is the same in both groups, but with a higher number of repeat procedures except in diabetic patients in whom mortality is higher after angioplasty. The use of coronary stents should reduce the number of post-angioplasty procedures. Constant technical improvements, the introduction of surgery without cardiopulmonary bypass, combined revascularisation procedures, new antiplatelet drugs, the absence of long-term comparative results, all this results in a personalized choice of revascularisation procedure based on the overall clinical and angiography features of each particular case.

Perivalvular abscesses associated with endocarditis; clinical features and prognostic factors of overall survival in a series of 233 cases. Perivalvular Abscesses French Multicentre Study.

AIMS: The purposes of this study were to determine the clinical features and to identify prognostic factors of abscesses associated with infective endocarditis. METHODS AND RESULTS: During a 5-year period from January 1989, 233 patients with perivalvular abscesses associated with infective endocarditis were enrolled in a retrospective multicentre study. Of the patients, 213 received medical surgical therapy and 20 medical therapy alone. No causative microorganism could be identified in 31% of cases. Sensitivity for the detection of abscesses was 36 and 80%, respectively using transthoracic and transoesophageal echocardiography. Surgical treatment consisted of primary suture of the abscess (38%), insertion of a felt aortic or mitral ring using Teflon or pericardium (42%), or debridment of the abscess cavity (20%). The 1 month operative mortality was 16%. Actuarial rates for overall survival at 3 and 27 months in operated patients were 75 +/- 10% and 59 +/- 11%, respectively. Increasing patient age, staphylococcal infection, and fistulization of the abscess were found to be independent risk factors in both 1 month and overall operative mortality. Renal failure was a risk factor predictive of operative mortality at 1 month, whereas uncontrolled infection and circumferential abscess were regarded as risk factors predictive of overall operative mortality. CONCLUSION: The data determined prognostic factors of abscesses associated with infective endocarditis.

Predictors of demand for emergency prehospital care: an Australian study.

INTRODUCTION: Determining the predictors of demand for emergency prehospital care can assist ambulance services in undertaking policy and planning activities. HYPOTHESIS: Demand for prehospital care can be explained by demographic, health status, and economic determinants. METHODS: The study used a cross-sectional design to investigate the association of demographic, health status, and insurance factors with the use of prehospital, ambulance care. Core data items including age, gender, marital status, country of origin, triage score, diagnosis, time of presentation, method of arrival, and patient disposition were collected for every patient who presented at the Emergency Department of the study hospital over a four-month period. Ambulance usage was analysed using Poisson regression. RESULTS: For the 10,229 patients surveyed, only a small number were triaged as having the highest level of urgent medical need (0.8%), but the majority of these used prehospital emergency medical care (90.2%). Predictors of ambulance use included age > 65 years (Prevalence Ratio [PR] = 2.92; 95% confidence interval [CI]: 2.35-3.63), being married or in a de-facto relationship (PR = 0.69; 95% CI: 0.60-0.79) or divorced, separated, or widowed (PR = 0.83; 95% CI: 0.70-0.98), triage score level 1 or 2 (PR = 1.95; 95% CI: 1.68-2.28), or triage score level 3 (PR = 1.54; 95% CI: 1.38-1.72), diagnosis involving either mental (PR = 4.29; 95% CI: 1.84-10.01), nervous (PR = 2.74; 95% CI: 1.19-6.31) or trauma (PR = 2.33; 95% CI: 1.03-5.27) conditions, and insurance status (PR = 1.54; 95% CI: 1.40-1.71). Ethnicity, gender, and time of day were not associated with usage. CONCLUSION: Demand for ambulance services can be predicted by a number of demographic, medical status, and insurance variables. Age and triage levels are key influences on demand for ambulance services. Ambulance insurance status provides an economic incentive to use ambulance services regardless of the urgency of the medical condition.

[Cardiac abscess in infectious endocarditis. A multicenter study apropos of 233 cases. The Working Group on Valvulopathy of the French Society of Cardiology]. / Abcès cardiaques dans l'endocardite infectieuse. Etude multicentrique à propos de 233 cas. Groupe de travail sur les valvulopathies de la Société française de cardiologie.

The aim of this retrospective multicenter study was to determine present characteristics of infectious endocarditis complicated by abscess and to identifying predictive factors of mortality. The files of 233 patients with infectious endocarditis complicated by perivalvular abscesses between January 1989 and December 1993 were analysed. Two hundred and thirteen patients underwent medico-surgical treatment (175 aortic and 38 mitral abscesses) and 20 patients underwent medical treatment alone (17 aortic and 3 mitral abscesses). The abscess was observed on native valves in 156 cases and valve prostheses in 77 cases. The causative organism was identified in 69% of cases : the commonest organism was the staphylococcus. The diagnostic sensitivity of transthoracic and transoesophageal echocardiography was 36 and 80% respectively. The operative mortality at one month was 16%. Patients over 65 years of age, staphylococcal infection, renal failure and fistulisation of the abscess, were identified as independent predictive factors of mortality at one month. The survival rate three months after surgery was 75 +/- 10% and 59 +/- 11% at 27 months. An age over 65, staphylococcal infection, uncontrolled infection, circumferential abscess and fistulisation were independent predictive factors of global mortality (the first month and after). The mortality rate in unoperated patients was 40%: cardiac failure and fistulisation of the abscess detected by echocardiography were predictive factors of mortality on univariate analysis.

[Complications of cardiac hydatid cyst. 2 cases]. / Complications du kyste hydatique cardiaque. 2 observations.

BACKGROUND: Cardiac localization of hydatiosis is uncommon, involving 0.5 to 2% of all cases. CASE REPORTS: The first patient was a 15 year old adolescent whose cardiac hydatidosis was revealed by tamponade. The second case was discovered in a 28-year-old woman without cardiac signs who was explored for allergy manifestations with fever, urticaria and joint point. Both patients underwent surgery. Eighteen months after the operation, the second patient developed hemiplegia leading to the discovery of multi-organ localizations (brain, spleen, kidney) which were not evidenced at the initial work-up. The neurological deficit and brain cysts regress with albendazole treatment. DISCUSSION: The risk of rupture of the cardiac hydatic cyst requires rapid surgical cure. Medical treatments are discussed. Anti-hydatic drugs can be used alone in case of a contraindication for surgery. In other patients they are given during the perioperatie period and for a prolonged period after surgery.

Changes in immediate outcome of percutaneous transluminal coronary angioplasty in multivessel coronary artery disease in 1990 to 1991 versus 1994 to 1995.

Coronary angioplasty has undergone major technical changes since the period of inclusion in the randomized trials, comparing it with surgery, particularly with the increased use of coronary stents. This study shows improved in-hospital outcome in terms of primary success and complication rates in patients treated with coronary angioplasty for multivessel disease from 1994 to 1995, compared with the 1990 to 1991 period.

[Reflections on external circulatory assistance. Apropos of 8 patients treated with the MEDOS system]. / Réflexions sur les assistances ventriculaires externes. A propos de huit patients traités par système MEDOS.

Mechanical circulatory support is required when cardiogenic shock is unresponsive to well conducted medical therapy. In this hemodynamic situation, when the patient's life is in danger, within hours, several questions should be answered quickly. These questions take into consideration the etiologies of cardiogenic shock and are related to the possibility of improvement of myocardial function, cardiac transplantation, the choice of uni- or biventricular support and surgical techniques of left ventricular assistance (left atrium to aorta or left ventricular apex to aorta). The follow-up of patients with circulatory support is complex. It requires to take into consideration hemodynamic, mechanical and hemobiological parameters as well as the peripheric organ function. We report in this article our clinical experience with eight patients that underwent circulatory support with Medos external ventricular assist device.

[Uni- or biventricular circulatory assist devices. Selection criteria and patients' follow-up, choice of device]. / Assistances uni- ou biventriculaires. Critères de sélection et de surveillance des patients, choix du dispositif.

Therapy of patients presenting with cardiogenic shock refractory to medical treatment can be undertaken with uni or biventricular circulatory assist devices. Pre implantation evaluation of patients is aimed at defining the etiology as well as the extent of uni versus biventricular heart failure, the possibility of recovery of myocardial function improvement of vital organ function and the possibility of cardiac transplantation. Circulatory assist devices must provide efficient support of the failing ventricles, allow recovery of myocardial function or cardiac transplantation under optimal circumstances. The choice of uni-biventricular support of total artificial heart is discussed as well as criteria useful in defining a therapeutic strategy.

Changes in patient treatment after abrupt closure complicating percutaneous transluminal coronary angioplasty: a historic perspective.

This study compares the incidence and management of acute closure complicating coronary angioplasty in three historic populations of patients having undergone the procedure at the same center: group 1 (n = 146 of 881) ("early years" of angioplasty, 1980 to 1986), group 2 (n = 113 of 1781) (bailout stenting learning curve, 1990 to 1992), and group 3 (n = 34 of 525) (1993). The incidence of acute closure decreased from group 1 (146 [17%] of 881) to groups 2 and 3 (147 [6%] of 2306); (p < 0.001). Management of the occlusion changed over the years, with less emergency coronary bypass surgery ([36%] 52 of 146, 15 [13%] 113, and 3 [9%] of 34), respectively, p < 0.01) and more repeat angioplasty (70 [48%] of 146; 87 [78%], of 113, and 30 [88%] of 34, p < 0.001). The use of prolonged inflations (> 10 minutes) and stenting increased from group 2 (15 [13%] of 113 and 16 [14%] of 113, respectively) to group 3 (12 [35%] of 34, and 10 [30%] of 34, respectively). In-hospital death occurred in 18 (12%) of 146, 7 (6%) of 113), and (2 (6%) of 34) patients in the three groups. Acute myocardial infarction decreased from 64% to 46% and 27%, respectively (p < 0.01). Overall, the number of patients free of events at hospital discharge increased from 38 (26%) of 146 to 53 (47%) of 113 (p < 0.001) and to 23 (68%) of 34 (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

[Development of indications in surgery of coronary revascularization. Current role of mammary-coronary anastomoses]. / Evolution des indications opératoires en chirurgie de revascularisation coronarienne. Place actuelle des anastomoses mammaro-coronariennes.

At a time when the cardio-surgical community has become aware that arterial revascularizations are superior to venous bypasses, GRUNTZIG (24) initiated the now well-known, and highly successful techniques of endoluminal angioplasty (P.T.C.A.) thus leading many teams to explore non-surgical revascularizations. These fast changing events somewhat overshadowed the interest placed in arterial anastomoses in general, and in particular, in mammary-coronary anastomoses. We believe that in 1993, many centres have not used this technique to its fullest and propose to the Académie de Chirurgie a programme of operative indications reinstating mammary-coronary anastomosis to its proper place in the treatment of coronary artery disease.

[Contribution of intra-operative measurement of intact parathormone in surgery for primary hyperparathyroidism]. / Apport du dosage per-opératoire de la parathormone intacte dans la chirurgie de l'hyperparathyroidie primaire.

Using a sensitive two-site immunoradiometric assay which detects intact parathormone (iPTH), we studied the decrease in peripheric and jugular plasmatic iPTH during surgical removal of abnormal parathyroid (s). In the next future, results of intact parathormone (iPTH) assay will be given in 45 minutes. In a prospective study of 33 patients operated on for hyperparathyroidism or for cold thyroid nodule, the serum levels of intact PTH was measured intraoperatively in peripheric and in jugular blood. The preoperative mean serum iPTH concentration was 119.23 +/- 172.48 pg/ml and fell to 34.5 +/- 32.21 pg/ml after surgery in 14 cases of primary hyperparathyroidism (p < 0.001). Thirteen out of 14 patients had serum iPTH values less than 65 pg/ml within 15 minutes after parathyroidectomy. The preoperative mean serum iPTH concentration in the 5 secondary hyperparathyroidism was 781.2 +/- 403.19 pg/ml. This value fell to 124 +/- 66.91 pg/ml after parathyroidectomy (p < 0.04). No significant decrease was observed in the mean serum concentration of the 14 patients operated on for cold thyroid nodule. Patients suffering from single parathyroid adenoma presented a significant gradient in jugular plasmatic PTH concentration between the adenoma side and the contralateral one. This gradient decreased during effective parathyroid adenomectomy (309.7 +/- 313.3 pg/ml to 3.7 +/- 35.1 pg/ml). Intraoperative serum iPTH concentration will provide a valuable tool to appreciate the effectiveness of surgical removal of parathyroid glands and to detect the location of parathyroid adenoma when the surgical research is negative.

Mycotic aneurysms of the carotid arteries--case report and review of the literature.

Mycotic aneurysms of the extracranial carotid arteries are rare. We report a new case with a mycotic aneurysm of the carotid bifurcation associated with acute bacterial endocarditis of the aortic valve. A concomitant treatment of both lesions was performed. Twenty-six cases of mycotic aneurysms of the extracranial carotid arteries have been reported in the literature. We present a review of all these cases.

Pelvic floor exercise versus surgery for female urinary stress incontinence.

Fifty consecutive female patients with genuine urinary stress incontinence were randomized either to surgery or to a pelvic floor training program. The operative procedure was chosen according to the type of bladder suspension defect on micturition cystourethrography. The training program was given 5 times in weekly lessons and the patients were guided by trained physiotherapists. Surgery was superior to the pelvic floor training program both subjectively and objectively. However, a significant improvement was found following the training program. Forty-two percent were satisfied with the outcome of the training and did not want operation. We find physiotherapist-guided pelvic floor exercise a realistic alternative to surgery in patients with mild degrees of stress incontinence. Also patients with residual symptoms after surgery are candidates for pelvic floor training.