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1.
Am J Cardiol ; 200: 204-211, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37354778

RESUMO

There is limited data on new-generation stent outcomes in patients with previous coronary artery bypass graft (CABG) and the associated risk of gender and race/ethnicity is unclear. We investigated 1-year outcomes after platinum chromium everolimus-eluting stent implantation in a diverse population of men, women, and minorities with previous CABG pooled from the PLATINUM Diversity (NCT02240810) and PROMUS Element Plus (NCT01589978) registries. Our primary outcome was major adverse cardiac events (MACE), a composite of all-cause death, myocardial infarction (MI), and target vessel revascularization (TVR) at 1-year post percutaneous coronary intervention (PCI). Secondary end points included all-cause death, MI, TVR, target vessel failure, and stent thrombosis. A total of 4,175 patients were included in the analysis, including 1,858 women (44.5%), 1,057 minorities (25.3%), and 662 (15.9%) with previous CABG. Patients with previous CABG were older, included more men and White patients, and had more co-morbidities compared with patients without previous CABG. At 1 year, patients with previous CABG had a higher risk of MACE (12.6% vs 7.5%, hazard ratio 1.70, 95% confidence interval 1.32 to 2.19, p <0.001) and end points, including death/MI, TVR, and target vessel failure. After multivariate adjustment, no differences were observed in MACE (adjusted hazard ratio 1.11, 95% confidence interval 0.82 to 1.49, p = 0.506) or any secondary end points. No interaction was observed between previous CABG and gender or minority status. In conclusion, in a contemporary PCI population, patients with previous CABG remain at high risk for PCI because of their elevated risk profile. Previous CABG status was however not independently associated with worse outcomes after adjustment, nor was any interaction observed with gender or race/ethnicity.


Assuntos
Doença da Artéria Coronariana , Stents Farmacológicos , Infarto do Miocárdio , Intervenção Coronária Percutânea , Feminino , Humanos , Masculino , Ponte de Artéria Coronária/efeitos adversos , Doença da Artéria Coronariana/complicações , Stents Farmacológicos/efeitos adversos , Infarto do Miocárdio/epidemiologia , Intervenção Coronária Percutânea/efeitos adversos , Platina , Sistema de Registros , Fatores de Risco , Resultado do Tratamento , Estudos Clínicos como Assunto
2.
Artigo em Inglês | MEDLINE | ID: mdl-38469035

RESUMO

Background: How diabetes mellitus (DM), race/ethnicity, and sex impact ischemic events following coronary artery stent procedures is unknown. Methods: Using the PLATINUM Diversity and PROMUS Element Plus Post-Approval Pooled Study (N = 4184), we examined the impact of race/ethnicity, sex, and DM on coronary stent outcomes. Primary outcome was 1-year major adverse cardiac events (MACE) (MACE composite: death, myocardial infarction [MI], and target vessel revascularization). Results: The study sample included 1437 diabetic patients (501 White men, 470 White women, 246 minority men, 220 minority women) and 2641 patients without medically treated DM (561 minority, 1090 women). Mean age (years) ranged from 61 in minority men to 65 in White women. Diabetic patients had a higher prevalence of atherosclerotic risk factors and comorbidities. Diabetic minority women (DMW; 70% Black, 27% Hispanic) had similar atherosclerotic risk factors to other diabetics, but experienced higher 1-year MACE (14.4% vs 7.5%, P <.01) and MI (4.3% vs 1.6%, P <.01) rates compared with patients without medically treated DM. No other diabetic cohort (White men, White women, minority men) showed an increased risk of MACE vs patients without medically treated DM. The incremental risk of MACE in DMW was associated with insulin use and persisted after risk adjustment (adjusted odds ratio 1.6 vs patients without medically treated DM; 95% CI, 1.0-2.5). Independent predictors of 1-year MACE included insulin use, hyperlipidemia, renal disease, and prior MI. Conclusions: DMW face the highest risk of ischemic events following coronary stenting, driven, in part, by insulin use. Aggressive secondary prevention and strict glycemic control are imperative in this cohort, and further research is warranted to elucidate the biologic mechanisms underpinning these observations. Clinical Trial Registration: NCT02240810 (http://clinicaltrials.gov/).

3.
Asian Bioeth Rev ; 13(4): 473-483, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34611464

RESUMO

Precision medicine (PM) aims to revolutionise healthcare, but little is known about the role religion and spirituality might play in the ethical discourse about PM. This Perspective reports the outcomes of a knowledge exchange fora with religious authorities in Singapore about data sharing for PM. While the exchange did not identify any foundational religious objections to PM, ethical concerns were raised about the possibility for private industry to profiteer from social resources and the potential for genetic discrimination by private health insurers. According to religious authorities in Singapore, sharing PM data with private industry will require a clear public benefit and robust data governance that incorporates principles of transparency, accountability and oversight. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s41649-021-00180-4.

6.
Catheter Cardiovasc Interv ; 94(1): 82-90, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30666784

RESUMO

OBJECTIVE: We evaluated 1-year outcomes after platinum chromium everolimus-eluting stents (PtCr-EES) in small versus non-small coronary arteries within a large, diverse sample of men, women, and minorities. BACKGROUND: There exists limited outcomes data on the use of second-generation drug-eluting stent to treat small diameter coronary arteries. METHODS: We pooled patients from the PLATINUM Diversity and PROMUS Element Plus stent registries. Small-vessel percutaneous coronary intervention (SV-PCI) was defined as ≥1 target lesion with reference vessel diameter (RVD) ≤2.5 mm. Endpoints included major adverse cardiac event (MACE; death, myocardial infarction [MI] or target vessel revascularization [TVR]), target vessel failure (TVF; death related to the target vessel, target vessel MI or TVR) and definite/probable stent thrombosis (ST). Multivariable Cox regression was used to risk-adjust outcomes. RESULTS: We included 4,155/4,182 (99%) patients with available RVD, of which 1,607 (39%) underwent small-vessel PCI. SV-PCI was not associated with increased MACE (adjHR 1.02; 95%CI 0.81-1.30) or TVF (adjHR 1.07; 95%CI 0.82-1.39). MI risk was lower in white men compared to women and minorities, both in the setting of SV-PCI (adjHR 0.41; 95%CI 0.23-0.74 and adjHR 0.39; 95%CI 0.20-0.75, respectively) and for non-SV-PCI (adjHR 0.61; 95%CI 0.38-0.99 and adjHR 0.45; 95%CI 0.27-0.74, respectively). There was no significant interaction between RVD and sex or minority status for any endpoint. CONCLUSION: In a large diverse contemporary PCI outcomes database, SV-PCI with PtCr-EES was not associated with increased MACE or TVR and did not account for the increased MI risk noted in women and minorities compared to white men.


Assuntos
Fármacos Cardiovasculares/administração & dosagem , Cromo , Doença da Artéria Coronariana/terapia , Stents Farmacológicos , Everolimo/administração & dosagem , Disparidades nos Níveis de Saúde , Saúde das Minorias , Intervenção Coronária Percutânea/instrumentação , Platina , Idoso , Fármacos Cardiovasculares/efeitos adversos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/etnologia , Doença da Artéria Coronariana/mortalidade , Trombose Coronária/etnologia , Trombose Coronária/mortalidade , Everolimo/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etnologia , Infarto do Miocárdio/mortalidade , Estudos Observacionais como Assunto , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Desenho de Prótese , Fatores Raciais , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Fatores de Tempo , Resultado do Tratamento , Estados Unidos/epidemiologia
7.
Asian J Neurosurg ; 13(1): 46-52, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29492119

RESUMO

INTRODUCTION: We aimed to assess the effect of anti-tyrosine kinase inhibitors (TKIs) (gefitinib) in overall survival (OS) of the glioblastoma multiforme (GBM) patients in the backdrop of mutational status of epidermal growth factor receptor (EGFR) and PTEN genes. MATERIALS AND METHODS: All the patients subjected to resection or biopsies were put on gefitinib, and radiotherapy was delivered as per the hospital protocol. EGFR and PTEN mutational spectrum was performed by single-strand conformation polymorphism followed by DNA sequencing. RESULTS: In total, 50% GBM tumors had mutation either in EGFR or PTEN. Median progression-free survival (PFS) and OS observed in patients with EGFR +ve/PTEN -ve were significantly favorable (P < 0.05) which aggregated to 9(7, 11) months and 20 (16, 24) months, respectively, than 6 (4, 8) months and 13 (7, 19) months in patients with PTEN +ve/EGFR -ve. Patients positive for both EGFR/PTEN had lower disease-free survival and OS of 6 and 9 months as compared to 6 (5, 7) and 14 (12, 24) months for those negative for both EGFR/PTEN. CONCLUSIONS: We conclude that EGFR gene alterations with wild-type PTEN are associated with significantly better PFS and OS in patients treated with anti-TKIs (gefitinib). Combined EGFR and PTEN gene mutation is associated with significantly poor response to gefitinib in terms of median OS.

8.
J Neurosurg Sci ; 2018 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-29444555

RESUMO

The article by Sajad ARIF, Arshad PANDITH, Rehana TABASUM, Altaf RAMZAN, Sarabjeet SINGH, Mushtaq SIDDIQI, Abdul BHAT entitled "SIGNIFICANT EFFECT OF ANTI-TYROSINE KINASE INHIBITOR (GEFITINIB) ON OVERALL SURVIVAL OF THE GLIOBLASTOMA (GBM) PATIENTS IN THE BACKDROP OF MUTATIONAL STATUS OF EGFR AND PTEN GENES" was published ahead of print in the Journal of Neurosurgical Sciences on February 13, 2018. As corresponding author of the article, Dr. Sajad ARIF declares that he and his group submitted the same manuscript to two different journals simultaneously (Journal of Neurosurgical Sciences and Asian J Neurosurg), with subsequent redundant publications. The authors confirm their responsibility and ask for the Epub ahead of print publication of their paper in the Journal of Neurosurgical Sciences to be withdrawn. The authors deeply regret this circumstance and apologize for this misconduct to the Journal of Neurosurgical Sciences, to the Asian J Neurosurg, as well as to the readers of the journals. The corresponding author, Sajad ARIF

10.
JAMA Cardiol ; 2(12): 1303-1313, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29049508

RESUMO

Importance: There exist limited outcomes data for women and minorities after contemporary percutaneous coronary intervention (PCI). Objective: To examine 1-year outcomes in women and minorities vs white men after PCI with everolimus-eluting stents. Design, Settings, and Participants: The PLATINUM Diversity study was a single-arm study enrolling women and minorities. Patient-level pooling with the PROMUS Element Plus Post-Approval Study was prespecified. Data on social determinants of health and language were collected in the PLATINUM Diversity cohort, which included 1501 patients at 52 US sites. The PROMUS Element Plus Post-Approval study enrolled 2681 patients at 52 US sites with some site overlap and included an "all-comers" population. All patients were enrolled beginning in October 2014 and were followed for 12 months. Analyses began in August 2016. Interventions: Patients received 1 or more everolimus-eluting stent implantation. Main Outcomes and Measures: The primary end point was 1-year major adverse cardiac events (MACE), which included death/myocardial infarction (MI)/target vessel revascularization. Secondary ischemic end points were also evaluated. Results: The pooled study consisted of 4182 patients: 1635 white men (39.1%), 1863 women (white and minority) (44.5%), and 1059 minority patients (women and men) (25.3%). Women and minorities had a higher prevalence of diabetes, prior stroke, hypertension, renal disease, and congestive heart failure than white men but lower rates of multivessel disease, prior coronary artery bypass graft surgery, prior MI, and smoking. Unadjusted 1-year MACE rates (white men, 7.6%; women, 8.6%; minorities, 9.6%) were similar between groups with no significant differences after risk adjustment. The adjusted risk of death/MI was higher among women (odds ratio, 1.6; 95% CI, 1.1-2.4) and minorities (odds ratio, 1.9; 95% CI, 1.2-2.8) compared with white men and the adjusted risk of MI was higher in minorities (odds ratio, 2.6; 95% CI, 1.4-4.8). These differences were driven primarily by nonstent-related MIs. Within the PLATINUM Diversity cohort, the independent predictors of MACE were cardiogenic shock, renal disease, history of peripheral vascular disease, multivessel disease, widowhood, and lack of private insurance. Conclusions and Relevance: After contemporary everolimus-eluting stent implantation, women and minorities experience a similar risk of 1-year MACE but a higher adjusted risk of recurrent ischemic events primarily because of nonstent-related MIs. Both clinical and angiographic factors and social determinants of health, including widowhood and insurance status, contribute to 1-year MACE among women and minorities.


Assuntos
Doenças Cardiovasculares/mortalidade , Doença da Artéria Coronariana/cirurgia , Stents Farmacológicos , Etnicidade , Grupos Minoritários , Infarto do Miocárdio/epidemiologia , Revascularização Miocárdica/estatística & dados numéricos , Intervenção Coronária Percutânea , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Everolimo/administração & dosagem , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Imunossupressores/administração & dosagem , Indígenas Norte-Americanos/estatística & dados numéricos , Seguro Saúde , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Prospectivos , Fatores Sexuais , Determinantes Sociais da Saúde , Resultado do Tratamento , Estados Unidos/epidemiologia , Viuvez
11.
Radiat Prot Dosimetry ; 175(4): 440-449, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28074019

RESUMO

To determine the effect of patient off-centering on point organ radiation dose measurements in a human cadaver scanned with routine abdominal CT protocol. A human cadaver (88 years, body-mass-index 20 kg/m2) was scanned with routine abdominal CT protocol on 128-slice dual source MDCT (Definition Flash, Siemens). A total of 18 scans were performed using two scan protocols (a) 120 kV-200 mAs fixed-mA (CTDIvol 14 mGy) (b) 120 kV-125 ref mAs (7 mGy) with automatic exposure control (AEC, CareDose 4D) at three different positions (a) gantry isocenter, (b) upward off-centering and (c) downward off-centering. Scanning was repeated three times at each position. Six thimble (in liver, stomach, kidney, pancreas, colon and urinary bladder) and four MOSFET dosimeters (on cornea, thyroid, testicle and breast) were placed for calculation of measured point organ doses. Organ dose estimations were retrieved from dose-tracking software (eXposure, Radimetrics). Statistical analysis was performed using analysis of variance. There was a significant difference between the trends of point organ doses with AEC and fixed-mA at all three positions (p < 0.01). Variation in point doses between fixed-mA and AEC protocols were statistically significant across all organs at all Table positions (p < 0.001). There was up to 5-6% decrease in point doses with upward off-centering and in downward off-centering. There were statistical significant differences in point doses from dosimeters and dose-tracking software (mean difference for internal organs, 5-36% for fixed-mA & 7-48% for AEC protocols; p < 0.001; mean difference for surface organs, >92% for both protocols; p < 0.0001). For both protocols, the highest mean difference in point doses was found for stomach and lowest for colon. Measured absorbed point doses in abdominal CT vary with patient-centering in the gantry isocenter. Due to lack of consideration of patient positioning in the dose estimation on automatic software-over estimation of the doses up to 92% was reported.


Assuntos
Abdome/diagnóstico por imagem , Doses de Radiação , Tomografia Computadorizada por Raios X , Cadáver , Humanos , Posicionamento do Paciente , Imagens de Fantasmas
12.
Indian J Dent Res ; 27(3): 317-22, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27411663

RESUMO

OBJECTIVE: The aim of this study was to determine the prevalence of malocclusion and orthodontic treatment need in 13-18-year-old schoolchildren of Nalagarh, Himachal Pradesh, India using the Index of Orthodontic Treatment need (IOTN) and to analyze the treatment needs between males and females and correlation between the esthetic component (AC) and dental health component (DHC) of IOTN. SUBJECTS AND METHODS: The sample comprised 2000 school children (1125 females and 875 males) who had not undergone orthodontic treatment. No radiographs, study casts, were used; IOTN was calculated from clinical examination. RESULTS: DHC results showed that little need for orthodontic treatment was found in 31.6% and moderate need in 30.85%. A great need was estimated at 37.55%. Severe contact point displacement of more than 4 mm was the most common occlusal feature in the definite treatment need group, followed by increased overjet, impeded eruption of teeth, and anterior or posterior cross bite. AC results showed that little need for orthodontic treatment was in 86.15%, moderate need in 8.90%, and great need in 4.95%. LIMITATIONS: Index does not consider midline discrepancy, soft tissue abnormalities, and AC does not include Class III and Class II div 2 malocclusion photographs. CONCLUSIONS: There seems a discrepancy in the proportion of children needing orthodontic treatment on esthetic and dental health grounds. This study provides baseline data on the need and demand for orthodontic treatment among the sample which is important for planning public orthodontic and dental services.


Assuntos
Necessidades e Demandas de Serviços de Saúde , Má Oclusão/epidemiologia , Ortodontia Corretiva , Criança , Feminino , Humanos , Índia/epidemiologia , Masculino , Prevalência
14.
Am J Ther ; 23(3): e905-10, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25828517

RESUMO

Vascular inflammation is a key component involved in the process of arthrosclerosis, which in turn increases the risk for cardiovascular injury. In the last 10 years, there have been many trials that looked at omega-3 fatty acids as a way to reduce cardiovascular risk. These trials observed the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the traditional lipid panel and found that both EPA and DHA reduce triglyceride (TG) level and increase high-density lipoprotein cholesterol (HDL-C) levels but also increase the low-density lipoprotein cholesterol (LDL-C) levels. In the 2 more recent trials, the MARINE and ANCHOR, EPA was given as an adjunct therapy to high-risk patients and not only was the traditional lipids measured but also examined the vascular inflammatory biomarkers. The results of these 2 trials not only showed reduction in cardiovascular risk because of reduction in vascular inflammation and reduction in the lipid panel but also showed that one of the MARINE-derived omega-3 fatty acid is superior to the other. Data search for omega-3 fatty acids and cardiovascular risk was performed, and articles were selected for review from 2006 to date. The research studies were all double-blind randomized trials except for one, which was a single-blind and focused on the effects of omega-3 fatty acids on the entire lipid panel. The participants received DHA/EPA and compared with a placebo group on the effect seen in the lipid panel. The first 7 studies looked at the effects of omega-3 fatty acids on TG, LDL-C, and HDL-C; of the 7, 1 directly compared DHA and EPA, 2 focused on EPA, and 4 were directed towards DHA alone. The MARINE and ANCHOR trials were more recent and also looked at the same parameter but also monitored vascular inflammatory biomarkers and how they were affected by omega-3 fatty acids. A second data search was performed for vascular biomarkers and cardiovascular risk, and articles that focused on high-sensitivity C-reactive protein and oxidized low-density lipoprotein were selected for review. Omega-3 fatty acids have shown to decrease TG level in multiple trials, but they have also shown to increase LDL and HDL levels, likely because omega-3 fatty acids promote TG conversion into HDL/LDL. The older data suggested that the benefits of omega-3 fatty acids are nullified by their effects on LDL levels. The data from the MARINE and ANCHOR trials have shown that EPA alone at 4 g per day has shown to decrease TG and total cholesterol without affecting the LDL levels. The earlier data showed that both EPA and DHA decreased TG level and increased levels of HDL-C, but that the DHA alone and direct comparison of DHA/EPA showed that DHA has more undesirable effects on LDL. Furthermore, the MARINE and ANCHOR trials have both shown that not only does EPA improve the lipid panel but also helps to decrease the levels of the vascular inflammatory biomarkers, thus further helping to decrease cardiovascular risk. The use of EPA as an adjunct therapy for high-risk patient has shown to help decrease cardiovascular risk. The reduction in risk is performed not only by decreasing TG but also by reducing vascular inflammation. Although because there are no randomized double-blind study looking at this, the research is inconclusive and requires further investigation.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Ácidos Docosa-Hexaenoicos/uso terapêutico , Ácido Eicosapentaenoico/uso terapêutico , HDL-Colesterol/sangue , Humanos , Fatores de Risco , Resultado do Tratamento , Triglicerídeos/sangue , Vasculite/prevenção & controle
15.
Int J Clin Pediatr Dent ; 8(3): 190-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26628853

RESUMO

INTRODUCTION: The aim of this study was to assess the relationship of chronological age with cervical vertebrae skeletal maturation, frontal sinus width and antegonial notch depth and a correlation, if any, among the three variables. MATERIALS AND METHODS: The samples were derived from lateral cephalometric radiographs of 80 subjects (40 males, 40 females; age range: 10 to 19 years). Cervical vertebral development was evaluated by the method of Hassel and Farman, frontal sinus width was measured by the method described by Ertürk and antegonial notch depth as described by Singer et al. The Pearson's correlation coefficients were estimated to assess the relationship of chronological age with cervical vertebrae skeletal maturation, frontal sinus width and antegonial notch depth. RESULTS: The Pearson's correlation coefficient were 0.855 (p < 0.001) between chronological age and cervical vertebrae skeletal maturation, and 0.333 (p < 0.001) between chronological age and frontal sinus width. CONCLUSION: A highly significant positive correlation was found between chronological age and cervical vertebrae skeletal maturation, and between chronological age and frontal sinus width. Nonsignificant correlation was found between chronological age and antegonial notch depth. How to cite this article: Singh S, Sandhu N, Puri T, Gulati R, Kashyap R. A Study of Correlation of Various Growth Indicators with Chronological Age. Int J Clin Pediatr Dent 2015;8(3): 190-195.

16.
J Hum Reprod Sci ; 8(3): 175-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26538862

RESUMO

Spermatids are the earliest male germ cells with haploid set of chromosomes. Spermatid injection was introduced in human assisted reproduction for the treatment of men with non-obstructive azoospermia. Spermatozoa can be recovered in half of patients with nonobstructive azoospermia. The use of spermatids for intracytoplasmic injection (ICSI) has been proposed for cases in which no spermatozoa can be retrieved. However, there are low pregnancy rates following ICSI using round spermatids from men with no elongated spermatids or spermatozoa in their testes. The in vitro culture of immature germ cells has been proposed as a means to improve this poor outcome. Oocyte activation rarely occurs when injected with a spermatid. Therefore, spermatid injection requires use of calcium ionophores for oocyte activation which is otherwise carried out by PLC zeta from mature sperms. This is the only option available for the nonobstructive azoospermic patients to have their own biological child.

17.
Med Phys ; 42(11): 6274-82, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26520720

RESUMO

PURPOSE: To present a noninvasive technique for directly measuring the CT bow-tie filter attenuation with a linear array x-ray detector. METHODS: A scintillator based x-ray detector of 384 pixels, 307 mm active length, and fast data acquisition (model X-Scan 0.8c4-307, Detection Technology, FI-91100 Ii, Finland) was used to simultaneously detect radiation levels across a scan field-of-view. The sampling time was as short as 0.24 ms. To measure the body bow-tie attenuation on a GE Lightspeed Pro 16 CT scanner, the x-ray tube was parked at the 12 o'clock position, and the detector was centered in the scan field at the isocenter height. Two radiation exposures were made with and without the bow-tie in the beam path. Each readout signal was corrected for the detector background offset and signal-level related nonlinear gain, and the ratio of the two exposures gave the bow-tie attenuation. The results were used in the geant4 based simulations of the point doses measured using six thimble chambers placed in a human cadaver with abdomen/pelvis CT scans at 100 or 120 kV, helical pitch at 1.375, constant or variable tube current, and distinct x-ray tube starting angles. RESULTS: Absolute attenuation was measured with the body bow-tie scanned at 80-140 kV. For 24 doses measured in six organs of the cadaver, the median or maximum difference between the simulation results and the measurements on the CT scanner was 8.9% or 25.9%, respectively. CONCLUSIONS: The described method allows fast and accurate bow-tie filter characterization.


Assuntos
Filtração/instrumentação , Proteção Radiológica/instrumentação , Radiometria/instrumentação , Contagem de Cintilação/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Transdutores , Cadáver , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Forensic Sci Med Pathol ; 11(4): 488-96, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26541472

RESUMO

PURPOSE: Interstitial fluid accumulation can occur in pleural, pericardial, and peritoneal spaces, and subcutaneous tissue planes. The purpose of the study was to assess if whole body CT examination in a postmortem setting could help determine the presence and severity of third space fluid accumulation in the body. MATERIALS AND METHODS: Our study included 41 human cadavers (mean age 61 years, 25 males and 16 females) who had whole-body postmortem CT prior to autopsy. All bodies were maintained in the morgue in the time interval between death and autopsy. Two radiologists reviewed the whole-body CT examinations independently to grade third space fluid in the pleura, pericardium, peritoneum, and subcutaneous space using a 5-point grading system. Qualitative CT grading for third space fluid was correlated with the amount of fluid found on autopsy and the quantitative CT fluid volume, estimated using a dedicated software program (Volume, Syngo Explorer, Siemens Healthcare). RESULTS: Moderate and severe peripheral edema was seen in 16/41 and 7/41 cadavers respectively. It is not possible to quantify anasarca at autopsy. Correlation between imaging data for third space fluid and the quantity of fluid found during autopsy was 0.83 for pleural effusion, 0.4 for pericardial effusion and 0.9 for ascites. The degree of anasarca was significantly correlated with the severity of ascites (p < 0.0001) but not with pleural or pericardial effusion. There was strong correlation between volumetric estimation and qualitative grading for anasarca (p < 0.0001) and pleural effusion (p < 0.0001). CONCLUSION: Postmortem CT can help in accurate detection and quantification of third space fluid accumulation. The quantity of ascitic fluid on postmortem CT can predict the extent of anasarca.


Assuntos
Autopsia , Líquido Extracelular/metabolismo , Tomografia Computadorizada Multidetectores , Imagem Corporal Total , Adulto , Idoso , Idoso de 80 Anos ou mais , Ascite/diagnóstico por imagem , Ascite/patologia , Bilirrubina/análise , Cadáver , Edema/diagnóstico por imagem , Edema/patologia , Feminino , Patologia Legal , Humanos , Masculino , Pessoa de Meia-Idade , Pericárdio/diagnóstico por imagem , Pericárdio/metabolismo , Pericárdio/patologia , Peritônio/diagnóstico por imagem , Peritônio/metabolismo , Peritônio/patologia , Pleura/diagnóstico por imagem , Pleura/metabolismo , Pleura/patologia , Derrame Pleural/diagnóstico por imagem , Derrame Pleural/patologia , Albumina Sérica/análise , Índice de Gravidade de Doença , Tela Subcutânea/diagnóstico por imagem , Tela Subcutânea/metabolismo , Tela Subcutânea/patologia
19.
J Clin Diagn Res ; 9(10): ZC59-62, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26557619

RESUMO

BACKGROUND: Temporomandibular joint (TMJ) disc disorders are one of the major concerns to the mankind and doctors in day to day life due to its complex nature and failure to treat these kinds of conditions successfully. OBJECTIVES: The aim of the present study was to evaluate the efficacy of arthrocentesis in patients suffering from TMJ disc disorders. MATERIALS AND METHODS: A total of 50 subjects suffering from TMJ disc disorders were selected and treated by arthrocentesis. The subjects were followed up for a period of one year. RESULTS: The mean maximal mouth opening prior to arthro-centesis was 32.13mm and after the procedure the mean maximal mouth opening was 46.6mm. The mean right and left lateral movements before arthrocentesis were 7.15mm and 7.59mm respectively, and the mean right and left lateral movements of 9.49 and 9.31 respectively were present after the procedure. The mean degree of pain before arthrocentesis was 8.7, and after the procedure the mean degree of pain was 1.13 as per the visual analogue scale. CONCLUSION: The findings of this study suggested potential utility of arthrocentesis in the management of TMJ disc disorders.

20.
J Comput Assist Tomogr ; 39(4): 489-98, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26182223

RESUMO

PURPOSE: To assess lesion detection and image quality of ultralow-dose (ULD) abdominal computed tomography (CT) reconstructed with filtered back projection (FBP) and 2 iterative reconstruction techniques: hybrid-based iDose, and image-based SafeCT. MATERIALS AND METHODS: In this institutional review board-approved ongoing prospective clinical study, 41 adult patients provided written informed consent for an additional ULD abdominal CT examination immediately after standard dose (SD) CT exam on a 256-slice multidetector computed tomography (iCT, Philips-Healthcare). The SD examination (size-specific dose estimate, 10 ± 3 mGy) was performed at 120 kV with automatic exposure control, and reconstructed with FBP. The ULD examination (1.5 ± 0.4 mGy) was performed at 120 kV and fixed tube current of 17 to 20 mAs/slice to achieve ULD radiation dose, with the rest of the scan parameters same as SD examination. The ULD data were reconstructed with (a) FBP, (b) iDose, and (c) SafeCT. Lesions were detected on ULD FBP series and compared to SD FBP "reference-standard" series. True lesions, pseudolesions, and missed lesions were recorded. Four abdominal radiologists independently blindly performed subjective image quality. Objective image quality included image noise calculation and noise spectral density plots. RESULTS: All true lesions (n, 52: liver metastases, renal cysts, diverticulosis) in SD FBP images were detected in ULD images. Although there were no missed or pseudolesions on ULD iDose and ULD SafeCT images, appearance of small low-contrast hepatic lesions was suboptimal. The ULD FBP images were unacceptable across all patients for both lesion detection and image quality. In patients with a body mass index (BMI) of 25 kg/m or less, ULD iDose and ULD SafeCT images were acceptable for image quality that was close to SD FBP for both normal and abnormal abdominal and pelvic structures. With increasing BMI, the image quality of ULD images was deemed unacceptable due to photo starvation. Evaluation of kidney stones with ULD iDose/SafeCT images was found acceptable regardless of patient size. Image noise levels were significantly lower in ULD iDose and ULD SafeCT images compared to ULD FBP (P < 0.01). CONCLUSIONS: Preliminary results show that ULD abdominal CT reconstructed with iterative reconstruction techniques is achievable in smaller patients (BMI ≤ 25 kg/m) but remains a challenge for overweight to obese patients. Lesion detection is similar in full-dose SD FBP and ULD iDose/SafeCT images, with suboptimal visibility of low-contrast lesions in ULD images.


Assuntos
Tomografia Computadorizada Multidetectores/métodos , Doses de Radiação , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Abdominal/métodos , Meios de Contraste , Divertículo/diagnóstico por imagem , Feminino , Humanos , Iopamidol , Nefropatias/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
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