Sir Harold Ridley: innovator of cataract surgery.

Cataract surgery has evolved greatly over the years, from the ancient practice of 'couching' where the lens is dislodged, to the modern surgical techniques of today. Sir Harold Ridley's invention of the intraocular lens (IOL) has altered the approach towards cataract surgery, benefitting individuals worldwide. This has been his most notable contribution, it is therefore interesting to explore the build up to this event and gain an understanding of the issues faced by Sir Ridley. This paper explores the significant events and key developments that influenced one of the most valuable innovations in the context of cataract surgery--the intraocular lens.

Thoracic aorta calcification detected by electron beam tomography predicts all-cause mortality.

BACKGROUND: The presence of coronary artery calcium (CAC) is an independent marker of increased risk of cardiovascular disease (CVD) events and mortality. However, the predictive value of thoracic aorta calcification (TAC), which can be additionally identified without further scanning during assessment of CAC, is unknown. METHODS: We followed a cohort of 8401 asymptomatic individuals (mean age: 53+/-10 years, 69% men) undergoing cardiac risk factor evaluation and TAC and CAC testing with electron beam computed tomography. Multivariable Cox proportional hazards models were developed to predict all-cause mortality based on the presence of TAC. RESULTS: During a median follow-up period of 5 years, 124 (1.5%) deaths were observed. Overall survival was 96.9% and 98.9% for those with and without detectable TAC, respectively (p<0.0001). Compared to those with no TAC, the hazard ratio for mortality in the presence of TAC was 3.25 (95% CI: 2.28-4.65, p<0.0001) in unadjusted analysis. After adjusting for age, gender, hypertension, dyslipidemia, diabetes mellitus, smoking and family history of premature coronary artery disease, and presence of CAC the relationship remained robust (HR 1.61, 95% CI: 1.10-2.27, p=0.015). Likelihood ratio chi(2) statistics demonstrated that the addition of TAC contributed significantly in predicting mortality to traditional risk factors alone (chi(2)=13.62, p=0.002) as well as risk factors+CAC (chi(2)=5.84, p=0.02) models. CONCLUSION: In conclusion, the presence of TAC was associated with all-cause mortality in our study; this relationship was independent of conventional CVD risk factors as well as the presence of CAC.

Non-HDL cholesterol is strongly associated with coronary artery calcification in asymptomatic individuals.

BACKGROUND: Growing evidence shows that non-high-density lipoprotein cholesterol (Non-HDL-C) is a strong and independent predictor of cardiovascular disease (CVD). Few studies have assessed the association between traditional lipid measures and subclinical end points. In this study we analyzed the association of Non-HDL-C, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG) with coronary artery calcium (CAC), a marker of subclinical atherosclerosis. METHODS: The study population consisted of 1611 consecutive asymptomatic individuals (67% men, mean age: 53+/-10 years) referred to a single electron beam tomography (EBT) facility for CAC screening. Multivariate logistic regression was used to test the association between increasing quartiles of lipid levels and presence of CAC score (CACS)>0 and CACS>or=100, with the lowest levels (first quartile) of lipid values as reference. RESULTS: Overall CACS of 0, 1-99, 100-399 and >or=400, were observed in 35%, 44%, 12% and 9% of the study subjects, respectively. The prevalence of CAC increased significantly across increasing quartiles of LDL-C, TG and Non-HDL-C (all p<0.0001), whereas CACS was significantly lower across increasing quartiles of HDL-C (p<0.001). In a multivariate model controlling for age, gender, race, cigarette smoking, hypertension, family history of coronary artery disease and obesity, there was a significant increase in the prevalence of CAC with increasing values of each lipid variable. In a multivariate model simultaneously controlling for increasing quartiles of the remaining lipid variables, only the association of Non-HDL-C with CACS>0 remained statistically significant (p=0.002). Similar results were observed with CACS>or=100 (p=0.038). CONCLUSION: In this study Non-HDL-C was more strongly associated with subclinical atherosclerosis than all other conventional lipid values. These data suggests that Non-HDL-C may be an important treatment target in primary prevention.

Cemento-ossifying fibroma--a rare case.

The concept of 'fibro-osseous lesions' of bone has evolved over the last several decades and now includes two major entities: fibrous dysplasia and ossifying fibroma, as well as the other less common lesions such as florid osseous dysplasia, periapical dysplasia, focal sclerosing osteomyelitis, proliferative periostitis of garrie, and ostitis deformans. The cemento-ossifying fibroma is a central neoplasm of bone as well as periodontium which has caused considerable controversy because of confusion regarding terminology and the criteria for its diagnosis. The cemento-ossifying fibroma is odontogenic in origin, whereas ossifying fibroma is of bony origin. This article reports a rare case of an 11-year-old male who came to us with the history of swelling in the maxillary anterior region causing difficulty in closing of mouth as well as in mastication.

Effect of patient visualization of coronary calcium by electron beam computed tomography on changes in beneficial lifestyle behaviors.

Despite convincing data demonstrating the benefits of aspirin (ASA), exercise, and dietary changes for both primary and secondary prevention of coronary heart disease, they remain underused. In this study, we assess whether higher coronary artery calcium (CAC) scores determined by electron beam computed tomography (EBCT) are associated with beneficial lifestyle behaviors in asymptomatic individuals. A total of 980 asymptomatic patients referred for EBCT risk assessment by their primary physician were sent a survey questioning them about health behaviors. We evaluated long-term ASA utilization, exercise, and dietary changes based on CAC using multivariable analysis. The study population consisted of 980 individuals (78% men, mean age 60 +/- 8 years) who were followed for a mean of 3 +/- 2 years after an initial EBCT scan. Overall, ASA initiation was lowest (29%) among those with CAC = 0, and gradually increased with higher CAC scores (1 to 99, 55%; 100 to 399, 61%; > or =400, 63%; p <0.001 for trend). Similarly, dietary changes and exercise were lowest (33% and 44%, respectively) among those with CAC = 0 and gradually increased with higher CAC scores (1 to 99, 40%; 100 to 399, 58%; > or =400, 56%; p <0.001 for trend for dietary changes; and 1 to 99, 62%; 100 to 399, 63%; > or =400, 67%; p <0.001 for trend for exercise). In multivariable analysis, greater baseline CAC was strongly associated with initiation of ASA therapy, dietary changes, and increased exercise. In conclusion, in addition to risk stratification of asymptomatic individuals, determination of CAC may also improve utilization of ASA therapy and behavioral modification.

Relationship between white blood cell count and Framingham Risk Score in asymptomatic men.

BACKGROUND: There is an independent association between white blood cell (WBC) and coronary heart disease (CHD) risk. However, the relationship between WBC and Framingham Risk Score (FRS) remains unclear. METHODS: This is a cross-sectional study on a consecutive sample of 520 white asymptomatic men (mean age 46 +/- 7 years) without CHD. The study population was divided into WBC quartiles (x10(9) cells/L): 1(st) quartile: 3.1-5.3 (n = 139), 2(nd) quartile: 5.4-6.1 (n = 129), 3(rd) quartile: 6.2-7.1 (n = 131), 4(th) quartile: >/=7.2 (n = 121), and into tertiles according to the 10-year FRS: 1(st) tertile (low risk <5%, n = 180, 35%), 2(nd) tertile (intermediate risk 5-12%, n = 210, 40%), 3(rd) tertile (high risk: >/=13%, n = 130, 25%). RESULTS: WBC correlated only weakly with FRS (r = 0.18, p = 0.001). Among individual components of FRS, WBC correlated minimally with smoking (r = 0.12, p = 0.003), systolic blood pressure (r = 0.07, p = 0.1), and high-density lipoprotein cholesterol (r = -0.06, p = 0.1). However, no correlation was observed with age (p = 0.3) and total cholesterol (p = 0.5). Nearly one third (31%) of men in the low-risk (FRS <5%) had WBC count in the 1(st) quartile compared to 20% of those classified as high risk (FRS >/=13%). The prevalence of WBC in the 4(th) quartile increased across FRS tertiles (18, 22, 32%) (p = 0.09). CONCLUSIONS: WBC correlates weakly with FRS or its individual components. Since WBC count is strongly related to CHD, WBC may reflect different components of cardiovascular risk, which might not be captured by traditional cardiovascular risk factors used in calculating FRS. Inflammatory biomarkers afford adjunctive value to FRS and may be used to improve CHD risk stratification.

Subclinical coronary atherosclerosis: racial profiling is necessary!

OBJECTIVES: We aim to review the studies comparing coronary calcification across different ethnic groups. BACKGROUND: There is still uncertainty regarding ethnic differences in the prevalence, progression, and risk of coronary artery disease. Clues to possible racial differences in rates of coronary heart disease (CHD) may be found by identifying subclinical disease. Coronary artery calcification (CAC) can be used to predict risk of CHD in both symptomatic and asymptomatic subjects. METHODS: Online databases were searched for studies assessing racial differences in CAC. RESULTS: Most of the published studies have shown that racial differences exist in the prevalence and severity of CAC. Whites have a higher prevalence of CAC as compared to African Americans and other ethnic groups even after adjustment for risk factors. These differences in CAC are even more pronounced in men and in the elderly. Data regarding the distribution of CAC in ethnic groups outside the United States are limited. Emerging evidence indicates that while several ethnic groups outside the United States tend to have a greater prevalence of CHD risk factors, their prevalence of CAC is lower, as compared with Americans. Thus, the data obtained in the United States may not be able to be fully extrapolated to populations outside the United States for assessment of CHD risk. CONCLUSIONS: The presence and extent of CAC varies among different racial groups within and outside the United States. The relationship between calcification and the incidence of CHD in these ethnic groups needs further exploration. Thus, it is important to develop ethnic specific CAC nomograms to more accurately determine the underlying CHD risk associated with CAC in these individuals. It will also be imperative to obtain outcome data and relate it to baseline levels of CAC to help us put in perspective the significance of racial differences in CAC and how they impact on cardiac risk prediction.

Assessment of cardiac function using multidetector row computed tomography.

In patients with suspected or documented heart disease, a precise quantitative and qualitative assessment of cardiac function is critical for clinical diagnosis, risk stratification, management and prognosis. Cardiac CT is increasingly being used in diagnosis of coronary artery disease. Initially multi-detector row computed tomography (MDCT) was used chiefly for detecting coronary artery stenosis and assessment of cardiac morphology. Electron beam computed tomography has been shown to provide a highly accurate ejection fraction (+/-1%), with 50 ms image acquisition per image. Retrospective electrocardiographic gating allows for image reconstruction in any phase of the cardiac cycle. Thus, end systolic and end diastolic images can be produced to assess ventricular volumes and function. Despite lower temporal resolution than electron beam computed tomography, the ability of MDCT to assess ejection fraction is preserved. In the assessment of cardiac function, MDCT has been shown to be in good agreement with echocardiography, cineventriculography, single photon emission computed tomography and magnetic resonance imaging. The fast technical development of scanner hardware along with multisegmental image reconstruction has led to rapid improvement of spatial and temporal resolution and significantly faster cardiac scans. The same data that is acquired for MDCT angiography can also be used for evaluation of cardiac function. Considering contrast media application, radiation exposure, and limited temporal resolution, MDCT solely for analysis of cardiac function parameters seems not reasonable at the present time. However, because the data is already obtained during coronary evaluation, the combination of noninvasive coronary artery imaging and assessment of cardiac function with MDCT is a suitable approach to a conclusive cardiac workup in patients with suspected coronary artery disease. MDCT seems suitable for assessment of cardiac function by MDCT when results are held in comparison to magnetic resonance imaging as the reference standard. Given the radiation dose and contrast requirement, referring a patient to MDCT only for evaluation of function is not warranted, but rather adds important clinical information to the already acquired data during retrospective triggering for MDCT angiography.

Association of increased cardiorespiratory fitness with low risk for clustering of metabolic syndrome components in asymptomatic men.

BACKGROUND: From a preventive aspect, it is especially important to investigate the lifestyle risk factors associated with cardiovascular disease (CVD). The purpose of this study was to determine the relationship of increasing metabolic syndrome (MS) components across increasing levels of estimated cardiorespiratory fitness (CRF) in asymptomatic young to middle-aged men. METHODS: We studied 449 consecutive asymptomatic men (47 +/- 7 years) who underwent a maximal treadmill exercise test according to the Bruce protocol. Cardiorespiratory fitness (CRF) was divided into tertiles based on metabolic equivalents (METs). The following MS components were studied: 1) waist circumference > 102 cm; 2) serum triglycerides > or = 150 mg/dL; 3) HDL cholesterol levels of < 40 mg/dL; 4) fasting blood glucose (FBG) > or = 110 mg/dL or 5) blood pressure > or = 130/85 mmHg or treated hypertension. Multinomial logistic regression was used to investigate the relationship between clustering of MS components and CRF as determined by metabolic equivalents (METs). We used polytomous logistic regression to determine the likelihood of clustering of increasing components of metabolic syndrome with intermediate (2nd tertile) and low (1st tertile) levels of CRF as compared to those with highest levels of CRF (3rd tertile). RESULTS: Overall in the study population, zero, 1, 2 and > or = 3 (i.e., metabolic syndrome) risk factors for MS were observed in 29% (n = 129), 26% (n = 118), 22% (n = 98) and 23% (n = 104) men, respectively. The mean METS achieved in the study population was 10 +/- 2 (range 4-20). Nearly half (49%) of individuals with the highest levels of CRF had no MS risk factors whereas only 18% of those with low CRF (METS < 9) had no MS risk factors. On the other end of the spectrum, the prevalence of MS (> or = 3 MS risk factors) increased significantly across decreasing levels of CRF (6, 22, 33% p < 0.0001 for trend). Multivariable polytomous logistic regression (adjusting for age, smoking, cholesterol-lowering therapy) demonstrated that individuals with low CRF (1st tertile of METS) compared to those with highest CRF had 3.1- (p = 0.001) and 11.8- (p < 0.0001) fold higher risk of having 2 and > or = 3 MS components, respectively. Similar results were observed when the analyses was repeated adjusting for Framingham risk score. CONCLUSIONS: Asymptomatic men with low levels of CRF have a greater likelihood for clustering of MS components and thus are at higher CVD risk. Further studies are needed to define the risk of cardiovascular disease in patients with intermediate levels of CRF and address which treatment strategies are most important given an individual's risk profile.

Increased level of cardiorespiratory fitness blunts the inflammatory response in metabolic syndrome.

OBJECTIVE: The presence of metabolic syndrome is associated with a higher degree of inflammation. We sought to assess whether the higher levels of cardiorespiratory fitness attenuate the levels of inflammation in people with metabolic syndrome. RESEARCH DESIGN AND METHODS: We studied 449 consecutive asymptomatic men (47+/-7 years) who underwent a maximal treadmill exercise test according to the Bruce protocol. Cardiorespiratory fitness was divided into tertiles based on metabolic equivalents (METs). White blood cells (WBC) (x10(9) cells/L) count was used as marker of inflammation. RESULTS: In our study population, 23% of the participants had the metabolic syndrome. The WBC count increased (p < 0.0001 for trend) with increasing number of risk factors for metabolic syndrome; however there was an inverse relationship (p < 0.0001 for trend) with increasing tertiles of fitness (6.47 cells x 10(9) cells/L for lowest tertile and 5.7 x 10(9) cells/L for highest tertile). Multiple linear regression analyses demonstrated that as compared to individuals with no MS risk factor, the WBC count remained significantly higher in men with metabolic syndrome in first tertile (regression coefficient: 1.2, 95% CI 0.4-2.0, p = 0.003) and second tertile (regression coefficient: 0.61, 95% CI 0.4-2.0, p = 0.02) of cardiorespiratory fitness, respectively. However, in the highest tertile of fitness no increase in level of WBC count was observed with increasing metabolic syndrome risk factors. CONCLUSION: Our findings suggest that in people with metabolic syndrome an increased level of physical fitness might exert its beneficial effect via attenuating inflammation.

Objective assessment of the trauma patient in a surgical intensive care unit.

A 6-month study using the Therapeutic Intervention Scoring System (TISS) to evaluate trauma patients admitted to a surgical intensive care unit showed a correlation between severity of illness and TISS score at the same time. The TISS is useful in the ICU, where numerous complex interventions are made in caring for acutely ill and injured patients.