Cervical cancer in the Hauts-Bassins region of Burkina Faso: Results of a screening campaign by visual inspection with acetic acid (VIA screening in Burkina Faso)

This study was conducted to describe the distribution of precancerous and cancerous lesions of the cervix uteri, enumerated during a mass screening in Burkina Faso. We conducted a cross-sectional study involving 577 women aged 18 to 60 years, carried out from November 23 to December 19, 2013, in the city of Bobo-Dioulasso and in the rural commune of Bama. Regarding the screening results, 89 participants (15.4%) were positive for pre-malignant cervical lesions. Chi-square testing and logistic regression analyses were conducted to identify the likelihood of cervical pre-cancer lesion in the women. Participants less than 29 years old were approximately 3 times more likely to have cervical lesions than participants >39 years. Participants who were parous (1-3 deliveries) and multiparous (four or more deliveries) were approximately 4 times more likely to present with cervical lesions than nulliparous women. Access to screening services is low in the Bobo-Dioulasso region. Further research should be conducted to understand the incidence and distribution of cervical precancerous and cancerous lesions in Burkina Faso. (Afr J Reprod Health 2022; 26[6]:97-103).

Proceedings of the Canadian Frailty Network Workshop: Identifying Biomarkers of Frailty to Support Frailty Risk Assessment, Diagnosis and Prognosis. Toronto, January 15, 2018.

The Canadian Frailty Network (CFN), a pan-Canadian not-for-profit organization funded by the Government of Canada through the Networks of Centres of Excellence Program, is dedicated to improving the care of older Canadians living with frailty. The CFN has partnered with the Canadian Longitudinal Study on Aging (CLSA) to measure potential frailty biomarkers in biological samples (whole blood, plasma, urine) collected in over 30,000 CLSA participants. CFN hosted a workshop in Toronto on January 15 2018, bringing together experts in the field of biomarkers, aging and frailty. The overall objectives of the workshop were to start building a consensus on potential frailty biomarker domains and identify specific frailty biomarkers to be measured in the CLSA biological samples. The workshop was structured with presentations in the morning to frame the discussions for the afternoon session, which was organized as a free-flowing discussion to benefit from the expertise of the participants. Participants and speakers were from Canada, Italy, Spain, United Kingdom and the United States. Herein we provide pertinent background information, a summary of all the presentations with key figures and tables, and the distillation of the discussions. In addition, moving forward, the principles CFN will use to approach frailty biomarker research and development are outlined. Findings from the workshop are helping CFN and CLSA plan and conduct the analysis of biomarkers in the CLSA samples and which will inform a follow-up data access competition.

Cannabis use and risk of schizophrenia: a Mendelian randomization study.

Cannabis use is observationally associated with an increased risk of schizophrenia, but whether the relationship is causal is not known. Using a genetic approach, we took 10 independent genetic variants previously identified to associate with cannabis use in 32 330 individuals to determine the nature of the association between cannabis use and risk of schizophrenia. Genetic variants were employed as instruments to recapitulate a randomized controlled trial involving two groups (cannabis users vs nonusers) to estimate the causal effect of cannabis use on risk of schizophrenia in 34 241 cases and 45 604 controls from predominantly European descent. Genetically-derived estimates were compared with a meta-analysis of observational studies reporting ever use of cannabis and risk of schizophrenia or related disorders. Based on the genetic approach, use of cannabis was associated with increased risk of schizophrenia (odds ratio (OR) of schizophrenia for users vs nonusers of cannabis: 1.37; 95% confidence interval (CI), 1.09-1.67; P-value=0.007). The corresponding estimate from observational analysis was 1.43 (95% CI, 1.19-1.67; P-value for heterogeneity =0.76). The genetic markers did not show evidence of pleiotropic effects and accounting for tobacco exposure did not alter the association (OR of schizophrenia for users vs nonusers of cannabis, adjusted for ever vs never smoker: 1.41; 95% CI, 1.09-1.83). This adds to the substantial evidence base that has previously identified cannabis use to associate with increased risk of schizophrenia, by suggesting that the relationship is causal. Such robust evidence may inform public health messages about cannabis use, especially regarding its potential mental health consequences.

Once versus twice daily aspirin after coronary bypass surgery: a randomized trial.

Essentials Coronary artery bypass graft (CABG) failure is associated with myocardial infarction and death. We tested whether more frequent dosing improves aspirin (ASA) response following CABG surgery. Twice-daily compared with once-daily dosing reduces ASA hyporesponsiveness after CABG surgery. The efficacy of twice-daily ASA needs to be tested in a trial powered for clinical outcomes. SUMMARY: Background Acetyl-salicylic acid (ASA) hyporesponsiveness occurs transiently after coronary artery bypass graft (CABG) surgery and may compromise the effectiveness of ASA in reducing thrombotic graft failure. A reduced response to ASA 81 mg once-daily after CABG surgery is overcome by four times daily ASA dosing. Objectives To determine whether ASA 325 mg once-daily or 162 mg twice-daily overcomes a reduced response to ASA 81 mg once-daily after CABG surgery. Methods Adults undergoing CABG surgery were randomized to ASA 81 mg once-daily, 325 mg once-daily or 162 mg twice-daily. The primary outcome was median serum thromboxane B2 (TXB2 ) level on postoperative day 4. We pooled the results with those of our earlier study to obtain better estimates of the effect of ASA 325 mg once-daily or in divided doses over 24 h. Results We randomized 68 patients undergoing CABG surgery. On postoperative day 4, patients randomized to receive ASA 81 mg once-daily had a median day 4 TXB2 level of 4.2 ng mL-1 (Q1, Q3: 1.5, 7.5 ng mL-1 ), which was higher than in those randomized to ASA 162 mg twice-daily (1.1 ng mL-1 ; Q1, Q3: 0.7, 2.7 ng mL-1 ) and similar to those randomized to ASA 325 mg once-daily (1.9 ng mL-1 ; Q1, Q3: 0.9, 4.7 ng mL-1 ). Pooled data showed that the median TXB2 level on day 4 in groups receiving ASA 162 mg twice-daily or 81 mg four times daily was 1.1 ng mL-1 compared with 2.2 ng mL-1 in those receiving ASA 325 mg once-daily. Conclusions Multiple daily dosing of ASA is more effective than ASA 81 mg once-daily or 325 mg once-daily at suppressing serum TXB2 formation after CABG surgery. A twice-daily treatment regimen needs to be tested in a clinical outcome study.

Molecular phenotype and bleeding risks of an inherited platelet disorder in a family with a RUNX1 frameshift mutation.

INTRODUCTION: Inherited defects in RUNX1 are important causes of platelet function disorders. AIM: Our goals were to evaluate RUNX1-related platelet disorders among individuals evaluated for uncharacterized, inherited platelet function disorders and test a proof of concept that bleeding risks could be quantitatively estimated for typical families with an inherited platelet function disorder. METHODS: Index cases with an uncharacterized inherited platelet function disorder were subjected to exome sequencing with confirmation of RUNX1 mutations by Sanger sequencing. Laboratory findings were obtained from medical records and persistence of platelet non-muscle myosin heavy chain IIB (MYH10), a biomarker of RUNX1 defects, was assessed by Western blotting. Bleeding histories were assessed using standardized assessment tools. Bleeding risks were estimated as odds ratios (OR) using questionnaire data for affected individuals compared to controls. RESULTS: Among 12 index cases who had their exomes sequenced, one individual from a family with eight study participants had a c.583dup in RUNX1 that segregated with the disease and was predicted to cause a frameshift and RUNX1 haploinsufficiency. Unlike unaffected family members (n = 2), affected family members (n = 6) had increased bleeding scores and abnormal platelet aggregation and dense granule release responses to agonists but only some had thrombocytopenia and/or dense granule deficiency. This family's mutation was associated with persistence of MYH10 in platelets and increased risks (OR 11-440) for wound healing problems and mild bleeding symptoms, including bleeding interfering with lifestyle in women. CONCLUSION: Inherited platelet dysfunction due to a RUNX1 haploinsufficiency mutation significantly increases bleeding risks.

Pain and Opioid Addiction: A Systematic Review and Evaluation of Pain Measurement in Patients with Opioid Dependence on Methadone Maintenance Treatment.

BACKGROUND: While chronic pain has been said to impact patient's response to methadone maintenance treatment for opioid dependence, the reported findings are inconsistent. These discrepancies may be a direct result of variations in the measurement of chronic pain or definitions of response to methadone treatment. The goal of this study is to evaluate the association between pain and substance use behaviour to determine the real impact of comorbid pain in the methadone population. We also aim to examine sources of variation across the literature with a specific focus on the measurement of pain. METHODS/DESIGN: We performed a systematic review using an electronic search strategy across CINAHL, MEDLINE, Web of Science, PsychINFO, EMBASE, and the Cochrane Library including Cochrane Reviews and the Cochrane Central Register of Controlled Trials databases. Title, abstract, as well as full text screening and extraction were performed in duplicate. Studies evaluating the association between chronic pain and methadone maintenance treatment response were eligible for inclusion in this review. Using a sample of 297 methadone patients from the Genetics of Opioid Addiction (GENOA) research collaborative, we assessed the reliability of patient self-reported pain and the validated Brief Pain Inventory (BPI) assessment tool. RESULTS: After screening 826 articles we identified five studies eligible for full text extraction, of which three showed a significant relationship between the presence of pain and the increase in substance abuse among patients on methadone for the treatment of opioid dependence. Studies varied largely in the definitions and measurement of both pain and response to treatment. Results from our validation of pain measurement in the GENOA sample (n=297) showed the use of a simple self-reported pain question is highly correlated to the use of the BPI. Simply asking patients whether they have pain showed a 44.2% sensitivity, 88.8% specificity, 84.4% PPV and 53.6% NPV to the BPI. The area under the ROC curve was 0.67 and the Pearson χ(2) was 37.3; (p<0.0001). DISCUSSION: The field of addiction medicine is at a lack of consensus as to the real effect of chronic pain on treatment response among opioid dependent patients. Whether it be the lack of a single "gold standard" measurement of response, or a lack of consistent measurement of pain, it is difficult to summarize and compare the results of these relatively small investigations. In comparison to the BPI, use of the simple self-reported pain has lower sensitivity for identifying patients with pain, suggesting the inconsistencies in these studies may result from differences in pain measurement. Future validation studies of pain measurement are required to address the predictive value of self-reported pain.

Use of genetic data to guide therapy in arterial disease.

There is considerable interindividual variation in the response to antiplatelet and anticoagulant therapies. It has been proposed that this variability in drug response may be attributable to genetic variants. Thus, pharmacogenetics may help to accurately predict response to cardiovascular disease (CVD) therapies in order to maximize drug efficacy, minimize drug toxicity, and to tailor personalized care for these patients. Although the clinical utility of pharmacogenetics is promising, its adoption in clinical practice has been slow. This resistance may stem from sometimes conflicting findings among pharmacogenetic studies. Thus, this review focuses on the genetic determinants of commonly used platelet antagonists and anticoagulants including aspirin, clopidogrel, dabigatran, and warfarin. We also explore the clinical translation of pharmacogenetics in the management of patients with CVD.

Active metabolite concentration of clopidogrel in patients taking different doses of aspirin: results of the interaction trial.

BACKGROUND: The CURRENT-OASIS-7 and PLATO trials suggest that the benefit of clopidogrel is influenced by the dose of aspirin. OBJECTIVE: To explore a potential pharmacokinetic interaction between aspirin and clopidogrel, and determinants of clopidogrel active metabolite (AM) levels. METHODS: In part 1, using a 2 × 2 factorial design, we randomized patients to clopidogrel 600 mg loading dose (LD) followed by 150 mg day(-1) for 6 days and 75 mg day(-1) thereafter, or clopidogrel 300 mg LD followed by 75 mg day(-1) thereafter, and compared aspirin at 325 mg or 81 mg day(-1) . In part 2, patients were given a 600-mg clopidogrel LD, and were randomly allocated to aspirin 325 mg or 81 mg day(-1) . We combine the data from the two parts. Blood samples were collected 1 h after administration of the study drug. RESULTS: We randomized 302 patients (mean age 60.4 ± 9.9 years). Clopidogrel AM levels were similar in patients randomized to aspirin 325 or 81 mg (geometric mean, 12.70 ng mL(-1) ; 95% CI, 10.96-14.72 ng mL(-1) ; and geometric mean, 12.55 ng mL(-1) ; 95% CI, 10.80-14.58 ng mL(-1) ; P = 0.91). Blood levels of clopidogrel were lower in CYP2C19*2 loss-of-function (LOF) carriers compared with non-carriers (10.72 ng mL(-1) ; 95% CI, 8.83-13.01 ng mL(-1) ; and 15.21 ng mL(-1) ; 95% CI, 13.30-17.40 ng mL(-1) , respectively; P = 0.003) whereas levels in gain of function carriers and non-carriers were similar (13.31 ng mL(-1) ; 95% CI, 11.53-15.35 ng mL(-1) ; and 14.07 ng mL(-1) ; 95% CI, 11.74-16.87 ng mL(-1) , respectively; P = 0.4). Independent baseline predictors of clopidogrel AM levels were LOF genotype, body mass index, diabetes, proton pump inhibitor use and creatinine clearance, but accounted for only 20% of the variability in levels. CONCLUSION: Aspirin dose does not predict clopidogrel AM levels 1 h post-LD. Most of the variability in clopidogrel AM levels is not explained by patient characteristics or CYP2C19 metabolizer status.

Multiple daily doses of acetyl-salicylic acid (ASA) overcome reduced platelet response to once-daily ASA after coronary artery bypass graft surgery: a pilot randomized controlled trial.

BACKGROUND: The efficacy of ASA for prevention of graft failure following CABG surgery may be limited by incomplete platelet inhibition due to increased post-operative platelet turnover. OBJECTIVES: To determine whether acetyl-salicylic acid (ASA) 325 mg once-daily or 81 mg four-times daily overcomes the impaired response to ASA 81 mg once-daily in post-operative coronary artery bypass graft (CABG) patients. METHODS: We randomized 110 patients undergoing CABG surgery to either ASA 81 mg once-daily, 81 mg four times daily or 325 mg once-daily and compared their effects on serum thromboxane B2 (TXB2 ) suppression and arachidonate-induced platelet aggregation. RESULTS: One hundred patients were included in the final analysis. Platelet counts fell after surgery, reached a nadir on day 2, and then gradually increased. Although there was near complete suppression of TXB2 on the second or third post-operative day, TXB2 levels increased in parallel with the rise in platelet count on subsequent days. This increase was most marked in patients receiving ASA 81 mg once-daily and less evident in those receiving ASA four times daily. On post-operative day 4, (i) median TXB2 levels were lower with four times daily ASA than with either ASA 81 mg once-daily (1.1 ng/mL; Quartile(Q) Q1,Q3: 0.5, 2.4 and 13.3 ng/mL; Q1,Q3: 7.8, 30.8 ng/mL, respectively; P < 0.0001) or ASA 325 mg once-daily (3.4 ng/mL; Q1,Q3: 2.0, 8.2 ng/mL; P = 0.002), and (ii) ASA given four times daily was more effective than ASA 81 mg once-daily and 325 mg once-daily at suppressing platelet aggregation. CONCLUSIONS: Four times daily ASA is more effective than ASA 81 and 325 mg once-daily at suppressing serum TXB2 formation and platelet aggregation immediately following CABG surgery.

The protective effect of the obesity-associated rs9939609 A variant in fat mass- and obesity-associated gene on depression.

Candidate gene and genome-wide association studies have not identified common variants, which are reliably associated with depression. The recent identification of obesity predisposing genes that are highly expressed in the brain raises the possibility of their genetic contribution to depression. As variation in the intron 1 of the fat mass- and obesity-associated (FTO) gene contributes to polygenic obesity, we assessed the possibility that FTO gene may contribute to depression in a cross-sectional multi-ethnic sample of 6561 depression cases and 21,932 controls selected from the EpiDREAM, INTERHEART, DeCC (depression case-control study) and Cohorte Lausannoise (CoLaus) studies. Major depression was defined according to DSM IV diagnostic criteria. Association analyses were performed under the additive genetic model. A meta-analysis of the four studies showed a significant inverse association between the obesity risk FTO rs9939609 A variant and depression (odds ratio=0.92 (0.89, 0.97), P=3 × 10(-4)) adjusted for age, sex, ethnicity/population structure and body-mass index (BMI) with no significant between-study heterogeneity (I(2)=0%, P=0.63). The FTO rs9939609 A variant was also associated with increased BMI in the four studies (ß 0.30 (0.08, 0.51), P=0.0064) adjusted for age, sex and ethnicity/population structure. In conclusion, we provide the first evidence that the FTO rs9939609 A variant may be associated with a lower risk of depression independently of its effect on BMI. This study highlights the potential importance of obesity predisposing genes on depression.

Exploring health information technology innovativeness and its antecedents in Canadian hospitals.

OBJECTIVES: The primary aim of this study was to assess the antecedents of health information technology (HIT) innovativeness in public hospitals. To do so, we built upon our own previous work to relate the level of HIT innovativeness to organizational capacity characteristics. METHODS: We conducted a survey of chief information officers (CIOs) in public hospitals in the two largest Canadian provinces to identify the level of HIT innovativeness in these settings and test nine research hypotheses derived from the proposed research model. RESULTS: A total of 106 completed questionnaires were received, which represents a response rate of 52%. Our findings indicate strong support for the research model. Seven out of nine hypotheses were supported indicating a significant relationship between HIT innovativeness and structural, financial, leadership, and knowledge sharing capacity characteristics. Results also reveal a moderate level of HIT innovativeness in the surveyed hospitals, with more emphasis on administrative systems and their integration than on clinical systems and emerging technologies. CONCLUSIONS: This study demonstrates that organizational characteristics are related to HIT innovativeness; this relationship holds irrespective of the public or private nature of hospitals.

Replacing an inpatient electronic medical record. Lessons learned from user satisfaction with the former system.

OBJECTIVE: Since it is important to develop strategies for the successful implementation of electronic clinical information systems, the aim of this study is to explore where, and to what extent, users' attitudes toward the former system that is being replaced may vary. METHODS: A cross-sectional survey of 346 nurses and physicians practicing in two Canadian teaching hospitals resulted in a total response rate of 63%. User attitudes were measured in three dimensions: a) user satisfaction with the system's quality attributes, b) perceived system usefulness, and c) perceived impact on quality of care and patient safety. The current system (the one being replaced) was analyzed as a dual system composed of both paper-based and electronic records. RESULTS: The results on user satisfaction demonstrate a wide variation in opinions, with satisfaction ranging from 4.2 to 7.7 on a 10-point disagree-agree, Likert scale. The quality attributes varied by record type, with differences that were systematically in favor of the electronic record component, which received higher scores. The results also highlighted large differences by user group. Physicians and nurses systematically rated the two record formats differently. The nurses were more satisfied with the attributes of the paper-based record. Multivariate regression analyses results also revealed strong interdependencies among the three dimensions of user attitudes, to the extent that perceived system usefulness was strongly correlated with system quality attributes and the system outcomes were also correlated, although less strongly, with the two former system dimensions. CONCLUSION: Understanding users' attitudes toward a clinical information system in use, both in its paper and electronic aspects, is crucial for developing more successful implementation strategies for electronic record systems.

Prioritizing the risk factors influencing the success of clinical information system projects. A Delphi study in Canada.

OBJECTIVE: The aim of this study is to gain a better understanding of the risk factors influencing the success of clinical information system projects. METHODS: This study addresses this issue by first reviewing the extant literature on information technology project risks, and second conducting a Delphi survey among 21 experts highly involved in clinical information system projects in Québec, Canada, a region where government have invested heavily in health information technologies in recent years. RESULTS: Twenty-three risk factors were identified. The absence of a project champion was the factor that experts felt most deserves their attention. Lack of commitment from upper management was ranked second. Our panel of experts also confirmed the importance of a variable that has been extensively studied in information systems, namely, perceived usefulness that ranked third. Respondents ranked project ambiguity fourth. The fifth-ranked risk was associated with poor alignment between the clinical information systems' characteristics and the organization of clinical work. The large majority of risk factors associated with the technology itself were considered less important. This finding supports the idea that technology-associated factors rarely figure among the main reasons for a project failure. CONCLUSIONS: In addition to providing a comprehensive list of risk factors and their relative importance, the study presents a major contribution by unifying the literature on information systems and medical informatics. Our checklist provides a basis for further research that may help practitioners identify the effective countermeasures for mitigating risks associated with the implementation of clinical information systems.

IT sophistication in hospitals : a field study in Quebec.

The Quebec health sector has been experiencing a period of great turmoil over the last five years and hospitals are faced with huge pressures from government funding cuts. Several empirical studies in the information systems field have shown that the use of computer-based information systems could have positive impacts on organizational performance. Many agree to say that health care institutions are no exceptions. But if one wishes to identify the effects of IT on the delivery of care, one must be able to characterize IT for operationalization purposes. Our main objective consists in developing and validating a measurement instrument of IT sophistication in hospitals. Such instrument should provide hospital managers with a diagnostic tool capable of indicating the profile of their respective institutions in regard to IT use and comparing this profile to those of other similar health institutions.

Effects of estrogen on the vascular injury response in estrogen receptor alpha, beta (double) knockout mice.

The two known estrogen receptors, ERalpha and ERbeta, mediate the effects of estrogen in all target tissues, including blood vessels. We have shown previously that estrogen inhibits vascular injury response to the same extent in female wild-type (WT), ERalpha knockout (ERalphaKO(CH)), and ERbeta knockout (ERbetaKO(CH)) mice. We generated mice harboring disruptions of both ERalpha and ERbeta genes (ERalpha,betaKO(CH)) by breeding and studied the effect of 17beta-estradiol (E2) on vascular injury responses in ovariectomized female ERalpha,betaKO(CH) mice and WT littermates. E2 inhibited increases in vascular medial area following injury in the WT mice but not in the ERalpha,betaKO(CH) mice, demonstrating for the first time that the two known estrogen receptors are necessary and sufficient to mediate estrogen inhibition of a component of the vascular injury response. Surprisingly, as in WT littermates, E2 still significantly increased uterine weight and inhibited vascular smooth muscle cell (VSMC) proliferation following injury in the ERalpha,betaKO(CH) mice. These data support that the role of estrogen receptors differs for specific components of the vascular injury response in the ERalpha,betaKO(CH) mice. The results leave unresolved whether E2 inhibition of VSMC proliferation in ERalpha,betaKO(CH) mice is caused by a receptor-independent mechanism, an unidentified receptor responsive to estrogen, or residual activity of the ERalpha splice variant reported previously in the parental ERalphaKO(CH) mice. These possibilities may be resolved by studies of mice in which ERalpha has been fully disrupted (ERalphaKO(St)), which are in progress.

Information technology sophistication in health care: an instrument validation study among Canadian hospitals.

Several empirical studies have shown that the use of computer-based information systems could have positive impacts on organizational performance. Many agree to say that health care organizations are no exceptions. But if one wishes to identify the effects of information technology (IT) on the delivery of care, one must be able to characterize IT for operationalization purposes. The primary objective of this research project is to develop and validate a measurement instrument of IT sophistication in the hospital milieu. Such instrument should provide hospital managers with a diagnostic tool capable of indicating the profile of their respective institutions in regard to IT adoption and comparing this profile to those of other similar medical centers. Both qualitative and quantitative data were collected in order to assess the psychometric properties of the measurement instrument. Overall, findings suggest a high-moderate level of functional sophistication, a somewhat low level of technological sophistication, and an even lower level of integration sophistication in all of the sampled medical centers. Hence, future investments shall therefore be directed towards the integration of clinical and administrative applications and the acquisition of more advanced technological devices, more specifically those, which allow direct capture of clinical data at the bedside.

The AIDS disease of CD4C/HIV transgenic mice shows impaired germinal centers and autoantibodies and develops in the absence of IFN-gamma and IL-6.

The mechanisms responsible for degeneration of germinal centers (GC) and follicular dendritic cell (FDC) networks during progression to AIDS remain elusive. Here, we show that CD4(+) T cells from CD4C/HIV-1 Tg mice, which develop a severe AIDS-like disease, express low levels of CD40 ligand. Accordingly, GC formation, FDC networks, and immunoglobulin isotype switching are impaired in these animals. However, Tg B cells respond to in vitro CD40 stimulation. Total serum IgG levels are reduced in Tg mice, whereas total IgM levels are increased with a significant amount showing DNA specificity. IFN-gamma- and IL-6-deficient CD4C/HIV Tg mice also develop the AIDS-like disease and produce auto-Ab. Thus, CD4C/HIV Tg mice have immune dysfunction accompanied by autoimmune responses.

Echomorphologic and histopathologic characteristics of unstable carotid plaques.

BACKGROUND AND PURPOSE: Our hypothesis was that the carotid plaques associated with retinal and cerebrovascular symptomatology and asymptomatic presentation may be differ from each other. The aim of this study was to identify the sonographic and histopathologic characteristics of plaques that corresponded to these three clinical manifestations. METHODS: The echo process involved duplex preoperative imaging of 71 plaques (67 patients, 21 plaques were associated with retinal, 25 with cerebrovascular symptoms, and 25 were asymptomatic), which was performed in a longitudinal fashion. Appropriate frames were captured and digitized via S-video signal in a computer and digitized sonograms were normalized by two echo-anatomic reference points: the gray scale median (GSM) of the blood and that of the adventitia. The GSM of the plaques was evaluated to distinguish dark (low-GSM) from bright (high-GSM) plaques. Subsequent to endarterectomy, the plaques were sectioned transversely, and a slice at the level of the largest plaque area was examined for the relative size of necrotic core and presence of calcification and hemorrhage. RESULTS: Retinal symptomatology was associated with a hypoechoic plaque appearance (median GSM: 0), asymptomatic status with a hyperechoic plaque appearance (median GSM: 34), and cerebrovascular symptomatology with an intermediate plaque appearance (median GSM: 16) (P = .001). The histopathologic characteristics did not disclose differences between the three clinical groups. The hypoechoic plaque appearance was associated only with the presence of hemorrhage (median GSM for the hemorrhagic plaques, 6, and for the non-hemorrhagic ones, 20 [P = .04]). The relative necrotic core size and the presence of calcification did not show any echomorphologic predilection. CONCLUSION: Our results showed that distinct echomorphologic characteristics of plaques were associated with retinal and cerebrovascular symptomatology and asymptomatic status. Histopathologically, only the presence of hemorrhage proved to have an echomorphologic predilection.

Reproducibility of computer-quantified carotid plaque echogenicity: can we overcome the subjectivity?

BACKGROUND AND PURPOSE: We sought to assess the reproducibility, interobserver variability, and application to clinical studies of a new method for the quantitative assessment of carotid plaque echogenicity. METHODS: Carotid plaques were scanned with the use of ultrasound, and their images were stored in a computer. They were normalized by assigning certain gray values to blood and adventitia, and the gray scale median (GSM) was used to quantify their echogenicity. The variability between storage media, between degrees of magnification, and between probes was assessed. The method was applied to 232 asymptomatic carotid plaques causing 60% to 99% stenosis in relation to the presence of ipsilateral CT-demonstrated brain infarcts. In all parts of the study the plaque GSM was measured before and after normalization to evaluate its effect. Interobserver agreement for the scanning process was assessed. RESULTS: The GSM mean difference before and after normalization for variability studies of storage media, degrees of magnification, and probes was -14.5 and -0.12, 2.24 and 1.68, and -8.3 and -0.7, respectively. The median GSM of plaques associated with ipsilateral nonlacunar silent CT-demonstrated brain infarcts was 14, and that of plaques that were not so associated was 30 (P:=0.003). The interobserver GSM difference was -0.05 (95% CI, -1.7 to 1.6). CONCLUSIONS: Our method decreases the variability between storage media and between probes but not the variability between degrees of magnification. It separates echomorphologically the carotid plaques associated with silent nonlacunar CT-demonstrated brain infarcts from plaques that are not so associated.

Comparability of the ultrasonic tissue characteristics of carotid plaques.

Hypoechoic carotid atherosclerotic plaques on ultrasonographic examination were found to be associated with cerebrovascular events. This underlines the need for an accurate evaluation of their echotexture characteristics. The objective of this study was to further validate a proposed method of normalization aiming to facilitate the comparability of these characteristics. The sonographic examination involved imaging of carotid plaques using duplex technique and capturing, digitization, and normalization in a computer in a standard way. In the first part, the interobserver and interscanner variability and the gain-level variability within the ultrasound unit were examined, before and after normalization, in terms of plaque echotexture. The second part investigated the effect of normalization on the echotexture of 419 symptomatic and asymptomatic plaques. Our results indicated that the normalization reduced the interscanner variability and the gain-level variability. The interobserver variability was excellent. In addition, this process further distinguished the echotexture characteristics of symptomatic and asymptomatic carotid plaques, which encourages the use of this method in natural history studies in persons with asymptomatic carotid atherosclerotic disease, aiming to identify those at higher risk for stroke. These patients might benefit from a carotid endarterectomy.