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PubMed2001

Performance of RVGui sensor and Kodak Ektaspeed Plus film for proximal caries detection.

OBJECTIVE: A high-resolution charge-coupled device was used to compare the diagnostic performances obtained with Trophy's new RVGui sensor and Kodak Ektaspeed Plus film with respect to caries detection. STUDY DESIGN: Three acquisition modes of the Trophy RVGui sensor were compared with Kodak Ektaspeed Plus film. Images of the proximal surfaces of 40 extracted posterior teeth were evaluated by 6 observers. The presence or absence of caries was scored by means of a 5-point confidence scale. The actual caries status of each surface was determined through ground-section histology. Responses were evaluated by means of receiver operating characteristic analysis. Areas under receiver operating characteristic curves (A(Z)) were assessed through analysis of variance. RESULTS: The mean A(Z) scores were 0.85 for film, 0.84 for the high-resolution caries mode, and 0.82 for both the low resolution caries mode and the high-resolution periodontal mode. These differences were not statistically significant (P =.70). The differences among observers also were not statistically significant (P =.23). CONCLUSION: The performance of the RVGui sensor in high- and low-resolution modes for proximal caries detection is comparable to that of Ektaspeed Plus film.

Analysis of Variance↗
PubMed2006

A texture-based method for modeling the background and detecting moving objects.

This paper presents a novel and efficient texture-based method for modeling the background and detecting moving objects from a video sequence. Each pixel is modeled as a group of adaptive local binary pattern histograms that are calculated over a circular region around the pixel. The approach provides us with many advantages compared to the state-of-the-art. Experimental results clearly justify our model.

Algorithms↗
PubMed2001

Molecular techniques in mycobacterial detection.

OBJECTIVE: To assess the clinical utility of the commercial nucleic acid amplification (NAA) tests (ie, Amplified Mycobacterium Tuberculosis Direct Test, Gen-Probe, Inc and AMPLICOR Mycobacterium tuberculosis Test, Roche Molecular Systems, Inc) for direct detection of Mycobacterium tuberculosis complex. DATA SOURCES: Review of the English-language literature. CONCLUSIONS: The performance of both NAA tests is excellent (sensitivity, > or = 95%; specificity, 100%) when testing respiratory specimens that are smear-positive for acid-fast bacilli (AFB). Only the Gen-Probe assay is approved for testing respiratory specimens regardless of the AFB smear result. Data from 3 studies showed that the sensitivity of the Mycobacterium Tuberculosis Direct Test in smear-negative patients ranged from 83% to 85%, and that the specificity was 99%. Both NAA tests have been used to test nonrespiratory specimens; in some studies, the performance was comparable to the performance obtained for respiratory specimens, whereas in others, it was lower. The NAA tests also appear to be reliable tools for rapid detection of M tuberculosis complex in positive broth cultures of all specimen types (except blood). The impact of the NAA tests on patient outcome varies based on the result of the AFB smear. In smear-positive patients, public health and hospital infection-control resources are predominantly affected. The potential for influencing patient outcome is much greater when the AFB smear is negative. In smear-negative patients, the NAA test could provide more rapid diagnosis of tuberculosis and subsequent initiation of therapy; eliminate the need for invasive diagnostic procedures, which are both costly and pose an added risk to the patient; and allow earlier discharge of hospitalized patients. Prospective studies concerning the cost-effectiveness of the NAA tests are needed.

Bacteriological Techniques↗
PubMed1996

Comparison of inversion recovery fast spin-echo (FSE) with T2-weighted fat-saturated FSE and T1-weighted MR imaging in bone marrow lesion detection.

OBJECTIVE: To prospectively compare inversion recovery (IR) fast spin-echo (FSE) with T1-weighted spin-echo (SE) and T2-weighted chemical-shift fat-saturated (FS) FSE magnetic resonance sequences in the detection of bone marrow abnormality. DESIGN: Twenty-nine sets of T1-weighted SE [400-640/10-20 (TR/TE)], T2-weighted FS-FSE [2400-3800/91-112/8 (TR/TE/ETL), and IR-FSE [3700-6000/12-14/170/8 (TR/TE/T1/ETL)] images were acquired with a 1.5-T magnet in 27 patients with bone marrow lesions. The visibility, margination, and extent of 41 lesions, image quality, contrast, and artifacts were qualitatively and quantitatively compared. RESULTS: The lesions were more conspicuous on the IR-FSE than on the T1-weighted SE and T2-weighed FS-FSE images. The extent of lesions was similar for all three sequences. Image quality was better and there were fewer motion artifacts on the T1-weighted images. The mean lesion contrasted-to-noise ratio was significantly higher on the T1-weighted images (p < 0.05). CONCLUSION: The IR-FSE sequence is highly sensitive for detecting bone marrow pathology, with scan time comparable to the T1-weighted SE and T2-weighted FS-FSE sequences.

Adult↗
PubMed2002

Survey of adverse drug reactions on a pediatric ward: a strategy for early and detailed detection.

OBJECTIVE: Adverse drug reactions (ADRs) occur frequently in children. However, the exact incidence of ADRs is unknown. Therefore, we studied ADRs in 1 ward and assessed whether a general approach, eg, by a computerized monitoring system, to detect ADRs in children is feasible and likely to yield a higher rate of early detected ADRs. The aim was to assess the usefulness of a computerized monitoring system before implementing costly adaptations. METHODS: An 8-month prospective study was conducted at a 10-bed pediatric isolation ward of the University Hospital. Charts were reviewed once weekly by a pharmacoepidemiological team. Clinical signs as well as laboratory changes were documented and assessed. Algorithms were used to assess the probability and severity of each detected event. RESULTS: All 214 patients admitted were enrolled in the study. A total of 68 ADRs were detected in 46 of 214 patients by the pharmacoepidemiological team. Thirty-four ADRs (50%) were detected by the staff physician, and 27 (40%) were detected primarily by analyzing laboratory parameters. Antibiotics-associated ADRs (50%) predominated, followed by glucocorticoids (16%), tuberculostatic (4%), and immunosuppressive agents (4%). In 5 cases, an ADR was responsible for the prolongation of hospital stay, and in 4 children, the ADR was responsible for hospitalization. CONCLUSIONS: The detection rate of ADRs would almost be doubled by a computerized monitoring system analyzing laboratory data. Implementation of a computer monitor system that automatically generates laboratory signals may help to identify ADRs in children, and to reduce morbidity and hospital stay, as well as costs.

Adolescent↗
PubMed1997

Hospital epidemiologic surveillance for invasive aspergillosis: patient demographics and the utility of antigen detection.

OBJECTIVE: To monitor the epidemiology of invasive aspergillosis at a university hospital during a period of hospital construction. To compare the efficacy of active epidemiologic surveillance for invasive aspergillosis using Aspergillus cultures with the efficacy of surveillance using Aspergillus antigen detection. DESIGN: A prospective surveillance study. SETTING: An 850-bed, tertiary-care, university-based hospital. PATIENTS: A convenience sample of 153 patients with Aspergillus antigen testing and culture. RESULTS: 24 cases were identified over a 12-month period; 7 were nosocomial, and 17 were community-acquired. Cases occurred primarily in patients with hematologic malignancy, but also occurred in patients with solid tumor, steroid treatment, cardiac transplant, and acquired immunodeficiency syndrome. Culture techniques identified only 14 (58%) of 24 cases, whereas Aspergillus antigen was positive in 19 (79%) of 24 cases tested. Epidemiological surveillance using either antigen or culture positivity detected 22 (92%) of 24 cases. In addition, antigen detection was 98% specific for the detection of aspergillosis, as compared to 91% for culture and 88% for antigen and culture combined. CONCLUSIONS: Hospital surveillance for aspergillosis should include determination of whether cases are nosocomial or community-acquired, because many may be the latter. Patients at risk for aspergillosis include patients without hematologic malignancies. Enhanced case detection occurred with active surveillance of patients considered to be at risk using both fungal serology and traditional microbiological techniques. Antigen detection was more sensitive and specific for the detection of invasive aspergillosis and may improve epidemiological surveillance for aspergillosis.

Antigens, Fungal↗
PubMed2006

Topical intranasal fluorescein: the missing partner in algorithms of cerebrospinal fluid fistula detection.

OBJECTIVE: The aim of this work was to focus on the development and validation of the use of topical fluorescein in the intraoperative localization of cerebrospinal fluid (CSF) fistulas, and to screen its use in preoperative diagnosis of CSF rhinorrhea as well as postoperative detection of a recurrence. MATERIALS AND METHODS: Twenty-five patients with CSF rhinorrhea were treated with an endoscopic endonasal technique. Topical intranasal 5% fluorescein was used for preoperative diagnosis and intraoperative localization of the site of the leak. A change in the color of the fluorescein from yellow to green fluorescence and sometimes streaming the fluorescein over the nasal mucosa and blood denoted the presence of CSF, and the site of the leak could be traced. RESULTS: The cause of the leak was accidental trauma in 11 patients, spontaneous in 9 patients, and iatrogenic in 5 patients. The ethmoidal roof was the most common site of leak (52%) followed by the cribriform plate (40%) and then the sphenoid sinus (8%). We have achieved 100% success rate in sealing the CSF fistulas in our 25 patients with no recurrence detected during the follow-up period (mean, 19+/-10 months). The preoperative use of fluorescein-soaked cotton pledgets was 100% accurate in diagnosing CSF rhinorrhea when compared with B2 transferrin testing. The intraoperative use of topical intranasal fluorescein was also 100% accurate in locating the site of the CSF fistula when compared with the surgical findings. No major complications have been reported. CONCLUSION: In the presence of a clinically diagnosed CSF leakage, topical fluorescein is a very easy, sensitive, safe, and highly accurate tool in the intraoperative localization of the site and extent of CSF fistulas, and should be considered a viable noninvasive alternative to intrathecal fluorescein. We also recommend its use as a simple and quick outpatient clinic test for preoperative diagnosis of CSF rhinorrhea. It can be used postoperatively as well when there is a doubt of recurrence of the CSF leak.

Administration, Intranasal↗
PubMedDate not supplied

Simultaneous determination of vitamin K analogs in human serum by sensitive and selective high-performance liquid chromatography with electrochemical detection.

OBJECTIVES: We report a sensitive and selective method for the simultaneous determination of vitamin K1 and K2 analogs (VKs) with high-performance liquid chromatography in which a platinum catalyst reduction column and an electrochemical detector operated in the oxidation mode are incorporated into the detection system. We also applied this trace analysis method to the simultaneous determination of VKs in human serum to investigate the physiologic and pathophysiologic roles of VKs in the bone metabolism. METHODS: Our high-performance liquid chromatographic method with postcolumn catalyst reduction and electrochemical detection was applied for the simultaneous determination of VKs in human serum samples. After separation of VKs on a reversed-phase separation column by using a mixture of ethanol and methanol (1:1, v/v), containing 0.025 M of sodium perchlorate as the mobile phase, the VKs were reduced once in a platinum catalyst reduction column connected online and then monitored quantitatively by an electrochemical detector with a glassy carbon working electrode operated in the oxidation mode (+0.6 V versus Ag/AgCl). RESULTS: VKs were clearly separated from each other within 80 min. The detection limits at a signal-to-noise ratio of 3 were 2 to 10 pg for VKs. Quantitative recovery from serum was obtained in the range of 86% to 91% for VKs. The average coefficients of variation of within-day and between-day assays were 1.6% to 2.1% and 2.4% to 3.6%, respectively, for all VKs. CONCLUSIONS: This method was sensitive and selective for detection of VKs and was satisfactory in the simultaneous determination of VKs in small volumes of human serum.

Bone and Bones↗
PubMed2006

[Determination of propofol in human serum by improved reversed phase high-performance liquid chromatography with fluorescence detection].

OBJECTIVE: To develop a new high-performance liquid chromatographic (HLPC) method for determination of propofol in human serum. METHODS: Human serum samples were precipitated with 20% perchloric acid and centrifuged to obtain 50 microl of the supernatant for analysis by HPLC coupled with fluorescence detection. The analysis was performed with a C(18) reversed-phase column using a acetonitrile-water (90:10) phase delivered at 1.0 ml/min, with the excitation wavelength of 276 nm and emission wavelength of 310 nm. RESULTS: The calibration curves were linear (r=0.997 5) within the concentration range of 0.05-10 microg/ml, the limit of propofol quantification was 50 ng/ml and the intra- and inter-day precisions were between -/+15%. CONCLUSIONS: The method is accurate, sensitive and simple for propofol determination in clinical anesthesia.

Anesthetics, Intravenous↗
PubMed2005

[Preparation of DNA from Cryptosporidium parvum oocysts for PCR detection].

OBJECTIVE: To establish three methods of DNA extraction from Cryptosporidium parvum oocysts and test by PCR. METHODS: After three freeze-thaw cycles, three kinds of templates were extracted from the oocysts by Chelex-100, phenol/chloroform or genomic DNA purification system kit, and used for PCR detection. According to the sequence of a C. parrum gene (L.16996), a pair of primers was designed and synthesized, and used for PCR. The sensitivity of the template by Chelex 100 method was also tested by PCR. RESULTS: One 446 bp PCR product was observed by agarose gel electrophoresis for all three kinds of templates. The PCR sensitivity by Chelex-100 extracted DNA reached for detection of a specimen containing only 1/2 oocyst. CONCLUSION: The three kinds of extraction can all be served as templates for PCR detection of C. parvum oocysts, while Chelex 100 method is simpler, quicker and more reliable for DNA extraction of the parasite.

Animals↗
PubMed1999

Insulin-like growth factor 1 (IGF-1), IGF-1 density, and IGF-1/PSA ratio for prostate cancer detection.

OBJECTIVES: Recent studies suggest an association between increased serum levels of insulin-like growth factor 1 (IGF-1) and an increased risk of prostate cancer (PCa). We prospectively analyzed the value of IGF-1, IGF-density (IGFD), and IGF-1/prostate-specific antigen (PSA) ratio for early detection of prostate cancer. METHODS: IGF-1, IGFD, and IGF-1/PSA ratio were determined prospectively during an 11-month period in the serum from 245 consecutive white men with PSA levels between 2.5 and 15 ng/mL. Octant biopsy (including transition zone biopsy) was performed. A second biopsy was performed 6 weeks later if the first biopsy was negative. Prostate volume was measured using transrectal ultrasound and the prolate ellipsoid method. Receiver operating characteristic curves were performed to compare tests. RESULTS: No evidence of malignancy was found in 174 patients (71%), and PCa was found in 71 (29%). The mean age for patients with no evidence of malignancy and those with PCa was 67.7+/-9 and 65.7+/-6 years, respectively (P = 0.17). IGF-1, IGFD, IGF-1/PSA ratio, and PSA were significantly higher in patients with PCa than in those with benign disease (P = 0.03, P = 0.045, P = 0.001, and P = 0.018, respectively). The area under the curve value derived from the receiver operating characteristic curves for IGF-1/PSA ratio, PSA, IGFD, and IGF-1 was 71%, 61%, 60%, and 58%, respectively. At 95% sensitivity, the specificity of the IGF-1/PSA ratio was significantly greater than that of all other parameters (P<0.0001 ). An IGF-1/PSA cutoff value of 25 afforded a 95% sensitivity for detecting PCa and would have avoided unnecessary biopsies in 24.1% of patients. CONCLUSIONS: Although IGF-1 and IGFD were unable to enhance the performance of PSA in our study, the IGF-1/PSA ratio significantly improved PCa detection over the use of PSA alone. Thus, increased IGF-1 levels (i.e., the IGF-1/PSA ratio) may not only be associated with an increased PCa risk but may also be a useful tool for early detection.

Aged↗
PubMed2005

[Dynamic monitoring of graft-versus-host disease after allogeneic peripheral blood stem cell transplantation by soluble HLA-I antigen detection].

OBJECTIVE: To assess the value of dynamic monitoring of soluble human lymphocytic antigen-I (sHLA-I) in the prediction of graft-versus-host disease (GVHD) after allogeneic peripheral blood stem cell transplantation (PBSCT). METHOD: Sandwich enzyme-linked immunosorbent assay (ELISA) was used to quantitatively detect serum sHLA-I. The serum samples for testing were added into W6 32 monoclonal antibody-coated microtiter plate and incubated with anti-beta2m HRP followed by color development with the addition of the substrate. Serum sHLA-I level was measured in 63 healthy blood donors of Shanghai and in 24 PBSCT recipients before and and at different time points after the operation. RESULT: No changes in sHLA-I levels occurred in allogeneic PBSCT recipients without GVHD or with only grade I GVHD, but sHLA-I reached high levels in patients suffering GVHD II-IV(P<0.05), which was effectively lowered by the application of immunosuppressants. CONCLUSION: Measurements of sHLA-I levels can be valuable for monitoring GVHD after PBSCT.

Adolescent↗
PubMed2000

Quantitative analysis of cytokeratin 20 gene expression using RT-PCR and capillary electrophoresis with fluorescent DNA detection.

OBJECTIVE: We developed a quantitative reverse-transcription polymerase chain reaction (RT-PCR) to determine CK20 expression in colorectal tumor and hematopoietic tissue. DESIGN AND METHODS: Our method incorporates a calibrated PCR with an internal competitor and an external standard. RESULTS: The RT-PCR assay is sensitive detecting 10 target molecules of CK20 in solution with one round of 38 amplification cycles. Genomic DNA contamination was eliminated by Dnase I digestion of total RNA. The inclusion of a calibrator in the quantitative RT-PCR analysis allowed for a high throughput of unknown samples within the same assay improving comparative analysis between the samples tested. Analysis of peripheral blood and bone marrow from 20 healthy volunteers revealed a low level of CK20 expression in all samples. CONCLUSION: To study the clinical significance of CK20 expression as a marker of systemic metastatic disease it is essential to measure CK20 mRNA levels in hematopoietic tissue with sensitive quantitative RT-PCR. A sensitive and reproducible method, which is easily performed, is described.

Biomarkers, Tumor↗
PubMed2004

Annoyance from multiple transportation noise: statistical models and outlier detection.

OBJECTIVE: Statistical models for the annoyance from multiple transportation noise are needed to understand and predict the annoyance resulting from specific noise exposures. METHODS: Models from the class of generalized linear models are suggested and discussed. Observations which are not well explained by the considered model are regarded as outliers. Outlier detection methods are applied to the data modelled by robust estimates using different link functions. RESULTS: The discussed methods are applied to data from a laboratory experiment using generalized linear models. While considering outliers, a generalized linear model with a complementary log-log link is found to be a good choice in modelling the exposure-response relationship between noise levels and annoyance.

Humans↗
PubMed1993

Prostate cancer trends in Canada: rising incidence or increased detection?

OBJECTIVES: To analyse trends in the incidence and mortality rates of prostate cancer in Canada according to age distribution, temporal pattern and provincial variation; to determine any association with the rate of prostatectomy; and to determine whether any observed increase in the rate of prostate cancer was due to an increase in the detection rate. DESIGN: Descriptive epidemiologic study based on Canadian population data from 1959 to 1989 and chart review from one Canadian hospital. SETTING: The chart review was conducted at the Ottawa Civic Hospital. SUBJECTS: The data on prostate cancer trends were obtained from the Canadian population. Charts were reviewed for two groups of patients: (a) men discharged from inpatient care during 1976 and 1986-87 with prostate cancer first diagnosed in the same year and (b) men who underwent transurethral resection of the prostate (TURP) during 1976 and 1986. OUTCOME MEASURES: Incidence and mortality rates of prostate cancer, rates of prostatectomy and TURP, and correlations between them. From the hospital data, changes between 1976 and 1986-87 in distribution of cancer stages, distribution of cases detected incidentally after surgery for suspected benign prostatic hypertrophy and average number of slides analysed per gram of tissue obtained from prostatectomy. RESULTS: The epidemiologic data showed that the age-adjusted incidence rates increased by 72% overall, an increase seen in all age groups over 60 years. The mortality rates increased by 29% overall, primarily in men over 85 years old. The prostatectomy rate increased by 55%. There were significant linear correlations between the national and provincial incidence rates of prostate cancer and the TURP rates. The chart review revealed that during 1976, 53% of the cases of prostate cancer diagnosed were localized, as compared with 75% in 1986-87 (p < 0.01). The proportion of tumours diagnosed incidentally in men undergoing TURP increased by 11%, whereas the number of procedures did not increase. Significantly more slides per gram of tissue were analysed in 1986-87 than in 1976 (p < 0.01). CONCLUSIONS: The correlations between the incidence rates of prostate cancer and those of TURP suggest that increased treatment of benign prostatic disease has led to increased detection of prostate cancer. Extrapolation of the data obtained from the chart review indicates that the increase in observed incidence rates can be attributed to an increase in the rate of localized disease and thus primarily to early detection rather than to elevated risk. However, because the rate of death from prostate cancer was elevated in elderly men, increases in exposure to unestablished risk factors cannot be ruled out.

Age Factors↗
PubMed2003

Hyperglycosylated hCG (invasive trophoblast antigen, ITA) a key antigen for early pregnancy detection.

OBJECTIVES: Hyperglycosylated human chorionic gonadotrophin (hCG) is an hCG variant with extra-large O-linked oligosaccharides, produced by phenotypically invasive cytotrophoblast cells in choriocarcinoma and pregnancy. It is the principal form of hCG produced in the first weeks of gestation. We investigated the importance of hyperglycosylated hCG in pregnancy testing and its detection by current hCG tests. DESIGN AND METHODS: We measured the concentration of hyperglycosylated hCG and total hCG in 512 pregnancies throughout gestation. We assessed and compared the abilities of 14 commonly used commercial laboratory hCG tests and 18 home pregnancy tests to detect regular and hyperglycosylated hCG. RESULTS: Hyperglycosylated hCG is the principal source of hCG-related immunoreactivity in early pregnancy. In the week following missing menses, hyperglycosylated hCG measurements may be more sensitive than regular hCG measurements in detecting pregnancy. Of 14 commercial laboratory hCG tests, 3 appropriately detected hyperglycosylated hCG standard. Of 18 different home pregnancy products 11 poorly or very poorly detected this key antigen. CONCLUSIONS: Hyperglycosylated hCG may be the key molecule in the detection of early pregnancy. However, the majority of tests poorly detected or failed to detect this key antigen. New pregnancy tests are needed that either solely detect hyperglycosylated hCG or equally detect regular hCG and hyperglycosylated hCG.

Antigens↗
PubMed2001

Ratio of nuchal thickness to humerus length for Down syndrome detection.

OBJECTIVE: Ultrasonographic biometry markers are now being used clinically to adjust Down syndrome risk. The limitations are that the definitions of "abnormal" measurements used are arbitrary, thus reducing screening performance, and also that patient-specific Down syndrome risks cannot be calculated. We report a new ultrasonographic algorithm that is sensitive for Down syndrome detection and that estimates individual risk. STUDY DESIGN: Overall in fetal populations with Down syndrome the humerus length is decreased, whereas the nuchal thickness is increased relative to that of a normal population. The nuchal thickness/humerus length ratio therefore shows an even greater increase and magnifies the separation between Down syndrome and healthy groups. Prospective data were collected in midtrimester amniocentesis cases. A regression equation for the median nuchal thickness/humerus length ratio based on biparietal partial diameter was generated. The Down syndrome likelihood ratio, or the odds on the basis of the nuchal thickness/humerus length ratio (multiples of the median), was multiplied by the age-related risk to give the posterior Down syndrome risk. Charts for rapid estimation of individual Down syndrome risk on the basis of maternal age and the nuchal thickness/humerus length ratio were constructed. RESULTS: There were 94 cases of Down syndrome and 4700 cases in which the karyotype was normal. The mean (+/-SD) gestational age of the study population was 16.1 +/- 1.6 weeks. Thirty-three fetuses with Down syndrome and 68 karyotypically normal fetuses had gross anomalies. The equation for the expected median nuchal thickness/humerus length ratio was as follows: 10e(1.7163 - 0.0292) x BPD + 0.0003 x BPD2, where BPD is the biparietal diameter. In the overall study population the nuchal thickness/humerus length ratio and maternal age had a 79.8% detection rate at a 22.1% false-positive rate, compared with maternal age plus humerus length (sensitivity, 55.1%) or maternal age plus nuchal thickness (sensitivity, 66.7%) at the same false-positive rate. For women > or =35 years old the values were 80% and 22.0%, respectively. CONCLUSIONS: We report an ultrasonographic biometry algorithm that, in combination with maternal age, detects 79.6% of Down syndrome cases in a high-risk group. Individual Down syndrome risk can be quickly calculated at the bedside and made available to women who desire this information before making a decision on amniocentesis. On the basis of published standards, ultrasonographic biometry as described would be a cost-effective alternative to amniocentesis in this high-risk group.

Algorithms↗
PubMed2002

Noninvasive visualization of coronary arteries using contrast-enhanced multidetector CT: influence of heart rate on image quality and stenosis detection.

OBJECTIVE: Although multidetector CT (MDCT) with retrospectively ECG-gated image reconstruction has been shown to permit noninvasive visualization of the coronary arteries, the 125-250 msec required for image acquisition frequently causes motion artifacts. We investigated the influence of a patient's heart rate on the presence of motion artifacts and on accuracy of stenosis detection on contrast-enhanced MDCT. MATERIALS AND METHODS: In 100 patients, MDCT was performed, and ECG-gated cross-sectional images were retrospectively reconstructed. From the 10 data sets obtained for each patient (reconstructed at 0-90% of the cardiac cycle in increments of 10%), we chose the best data set for every coronary artery. The images of the arteries were evaluated for occurrence of artifacts and the presence of high-grade stenosis (diameter reduction exceeding 70%) or occlusions. MDCT results were compared with coronary angiographic findings. RESULTS: Of the 400 coronary arteries, 115 (29%) could not be evaluated because of motion artifacts (n = 84) or other reasons (n = 31). Overall, 51 (49%) of 104 stenoses were revealed on MDCT. For detecting stenosis in those arteries that we could evaluate, MDCT had a sensitivity of 91% (51 of 56 stenoses detected) and a specificity of 89%. As the heart rate increased, the number of arteries that could be evaluated decreased, and overall sensitivity for stenosis detection decreased from 62% (heart rate < or = 70 beats per minute) to 33% (heart rate > 70 beats per minute). CONCLUSION: MDCT can reveal coronary stenoses, but the usefulness of MDCT as an aid in accurately evaluating stenoses decreases as a patient's heart rate increases.

Adult↗