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1.
J Psychiatr Res ; 45(7): 855-62, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21524424

ABSTRACT

This study used a comprehensive, interview-based measure of life stress to assess the role of different types of stress in predicting first onset of psychiatric disorders among daughters of depressed (n = 22) mothers and healthy (n = 22) mothers. Several types of stress were assessed: Chronic interpersonal stress, chronic non-interpersonal stress, episodic dependent (i.e., self-generated) interpersonal stress, episodic dependent non-interpersonal stress, episodic independent interpersonal stress, and episodic independent non-interpersonal stress. Daughters (ages 9-14) were recruited to have no clinically significant symptoms upon entry (T1). By a 30-month follow-up assessment (T2), 45% of the daughters of depressed mothers, but none of the daughters of healthy mothers, had developed a psychiatric disorder. Overall, daughters of depressed mothers were exposed to more severe chronic interpersonal and non-interpersonal stress than were daughters of healthy mothers. Further, daughters of depressed mothers who developed a psychiatric disorder by T2 were exposed to more severe chronic non-interpersonal stress and episodic dependent stress than were daughters of depressed mothers who remained healthy. We discuss the implications of these findings in the context of a stress-generation model for the intergenerational transmission of psychiatric risk among children of depressed mothers.


Subject(s)
Child of Impaired Parents/psychology , Depressive Disorder, Major/psychology , Life Change Events , Mental Disorders/psychology , Adolescent , Adult , Anxiety, Separation/epidemiology , Anxiety, Separation/psychology , Attention Deficit Disorder with Hyperactivity/epidemiology , Attention Deficit Disorder with Hyperactivity/psychology , Attention Deficit and Disruptive Behavior Disorders/epidemiology , Attention Deficit and Disruptive Behavior Disorders/psychology , Child , Cross-Sectional Studies , Depressive Disorder, Major/epidemiology , Female , Humans , Interpersonal Relations , Longitudinal Studies , Mental Disorders/epidemiology , Personality Assessment/statistics & numerical data , Psychometrics , Risk Factors , Substance-Related Disorders/epidemiology , Substance-Related Disorders/psychology
2.
Radiology ; 239(3): 768-76, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16714460

ABSTRACT

PURPOSE: To retrospectively determine if three-dimensional (3D) viewing improves radiologists' accuracy in classifying true-positive (TP) and false-positive (FP) polyp candidates identified with computer-aided detection (CAD) and to determine candidate polyp features that are associated with classification accuracy, with known polyps serving as the reference standard. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained; this study was HIPAA compliant. Forty-seven computed tomographic (CT) colonography data sets were obtained in 26 men and 10 women (age range, 42-76 years). Four radiologists classified 705 polyp candidates (53 TP candidates, 652 FP candidates) identified with CAD; initially, only two-dimensional images were used, but these were later supplemented with 3D rendering. Another radiologist unblinded to colonoscopy findings characterized the features of each candidate, assessed colon distention and preparation, and defined the true nature of FP candidates. Receiver operating characteristic curves were used to compare readers' performance, and repeated-measures analysis of variance was used to test features that affect interpretation. RESULTS: Use of 3D viewing improved classification accuracy for three readers and increased the area under the receiver operating characteristic curve to 0.96-0.97 (P<.001). For TP candidates, maximum polyp width (P=.038), polyp height (P=.019), and preparation (P=.004) significantly affected accuracy. For FP candidates, colonic segment (P=.007), attenuation (P<.001), surface smoothness (P<.001), distention (P=.034), preparation (P<.001), and true nature of candidate lesions (P<.001) significantly affected accuracy. CONCLUSION: Use of 3D viewing increases reader accuracy in the classification of polyp candidates identified with CAD. Polyp size and examination quality are significantly associated with accuracy.


Subject(s)
Colonic Polyps/diagnostic imaging , Colonography, Computed Tomographic/methods , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Adult , Aged , Colonography, Computed Tomographic/statistics & numerical data , Diagnosis, Computer-Assisted , False Positive Reactions , Female , Humans , Male , Middle Aged , Reference Standards , Retrospective Studies
3.
Acad Radiol ; 13(2): 249-53, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16428062

ABSTRACT

RATIONALE AND OBJECTIVES: Diagnostic ultrasound examinations may be performed after-hours by physicians if technologists are not available or cases are complex. Our experience suggested there is wide variability in how ultrasound coverage is provided after-hours, which motivated us to conduct a formal survey of teaching programs around the country. METHODS: Four hundred five members of the Association of Program Directors in Radiology were contacted by e-mail and sent a link to a five-part questionnaire posted on the Web. Respondents were asked whether ultrasound cases after-hours are performed in their institutions by radiology residents, technologists on the premises after-hours, technologists on-call, or some combination. Data on the type of program, number of beds in the primary hospital, number of residents in the program, and geographic location of the program were recorded. Responses were automatically written to a data file stored on a Web server and the imported into an Excel spreadsheet for data analysis. A chi(2) analysis was performed to assess associations among the variables and statistical significance. RESULTS: A total of 79 programs responded to the survey. Of those, 32% provided coverage with ultrasound technologists on call, 24% by ultrasound technologists on the premises, 13% provided combination coverage, and 10% provided coverage solely with residents on call. There was no association among number of residents in the program, location of the program, or type of program (university, community, or affiliated) and type of coverage provided. CONCLUSION: There is wide variability in methods for providing coverage of after-hours ultrasound cases. However, on-site or on-call coverage of emergency cases by technologists did not appear to depend significantly on program location, program type, or program size.


Subject(s)
After-Hours Care/organization & administration , Emergency Service, Hospital/organization & administration , Hospitals, Teaching/organization & administration , Personnel Staffing and Scheduling , Ultrasonography, Interventional , Health Care Surveys , Hospitals, Community , Hospitals, Military , Humans , Internship and Residency , Organizational Affiliation , Radiology Department, Hospital , United States , Work Schedule Tolerance
4.
Soc Sci Med ; 62(5): 1278-90, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16174544

ABSTRACT

Genomics integrates the promises and perils of modern biomedical science. Canada and the province of Québec embarked late but aggressively in genomics research based on the 'discourse of promise' in which genomics is embedded. This did not prevent the emergence of a 'discourse of concerns', and debates on the wider meaning of genomics and on the risks related to genomics applications such as gene therapy and gene testing. Given this context, this study aims to understand the evolution of genomics press coverage from the early days up to the publication of the draft sequence of the human genome. Accordingly, we performed a press content analysis on 749 articles reporting genomics research in Québec from 1992 to 2001. We focused on coverage of benefits and ethical issues, tone, and differences in reporting practices between press agencies and journalists. Results show an increasing number of articles, a general decline in the proportion of articles featuring ethical issues, an increased focus on the economy, and greater optimism from 1992 to 2001. In comparison to articles written by journalists, articles signed by press agencies are more optimistic and less often feature ethical issues. Results are discussed following two non-exclusive interpretations: (1) the successes of genomics and its institutionalization in Québec and Canada brought hype and greater social acceptance, and (2) uncritical reporting practices have emerged under pressures for expedient and consumable writing. We are left with two concerns: given worldwide media concentration movements, what are the challenges for the dissemination of diversified and critical information in print media? And, given limited coverage of ethical issues, and concerns about bioethics being too narrowly focused, should public debates on frontier biomedical science be promoted to broaden the scope of biomedical ethics?


Subject(s)
Bibliometrics , Genomics , Journalism, Medical , Bioethical Issues , Biomedical Research , Canada , Genomics/ethics , Information Dissemination , Journalism, Medical/standards , Quebec
5.
Radiology ; 236(3): 1029-33, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16020561

ABSTRACT

Study was approved by the institutional review board, and informed patient consent was waived. A method for minimization of sources of variability in measuring single-kidney extraction fraction (EF) was determined retrospectively with contrast material-enhanced computed tomography (CT). Ten adults underwent CT of the kidneys; precontrast scans were obtained, followed by postcontrast scanning 2 minutes after contrast material injection. Single-kidney EF was then calculated for each patient with the formula EF = (CT(A) - CT(V))/(CT(A) - CT(PRE)), where CT(A) and CT(V) are the postcontrast CT values (in Hounsfield units) of the systemic blood and renal venous blood, respectively, and CT(PRE) is the precontrast CT value of the blood. Both conventional two-dimensional and volumetric three-dimensional regions of interest were used for determining mean CT values of the blood. By using the volumetric regions of interest, left and right renal EF values averaged 17.3% and 18.0%, respectively, for two observers, compared with the accepted value of 15%-20%. This latter technique also minimized right-left kidney and interobserver variability in the measurement of EF.


Subject(s)
Glomerular Filtration Rate , Kidney/diagnostic imaging , Tomography, X-Ray Computed/methods , Adult , Aged , Contrast Media , Female , Humans , Iohexol , Male , Middle Aged , Retrospective Studies
6.
J Am Coll Surg ; 200(4): 527-37, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15804466

ABSTRACT

BACKGROUND: We performed this study to determine rates of close or transected cancer margins after magnetic resonance imaging-guided bracket wire localization for nonpalpable breast lesions. STUDY DESIGN: Of 243 women undergoing MRI-guided wire localizations, 26 had MRI bracket wire localization to excise either a known cancer (n = 19) or a suspicious MRI-detected lesion (n = 7). We reviewed patient age, preoperative diagnosis, operative intent, mammographic breast density, MRI lesion size, MRI enhancement curve and morphology, MRI Breast Imaging Reporting and Data System (BI-RADS) assessment code, number of bracket wires, and pathology size. We analyzed these findings for their relationship to obtaining clear margins at first operative excision. RESULTS: Twenty-one of 26 (81%) patients had cancer. Of 21 patients with cancer, 12 (57%) had negative margins at first excision and 9 (43%) had close/transected margins. MRI size > or = 4 cm was associated with a higher reexcision rate (7 of 9, 78%) than those < 4 cm (2 of 12, 17%) (p = 0.009). MRI BI-RADS score, enhancement curve, morphology, and preoperative core biopsy demonstrating ductal carcinoma in situ (DCIS) were not predictive of reexcision. The average number of wires used for bracketing increased with lesion size, but was not associated with improved outcomes. On pathology, cancer size was smaller in patients with negative margins (12 patients, 1.2 cm) than in those with close/transected margins (9 patients, 4.6 cm) (p < 0.001). Reexcision was based on close/transected margins involving DCIS alone (6, 67%), infiltrating ductal carcinoma and DCIS (2, 22%), or infiltrating ductal carcinoma alone (1, 11%). Reexcision pathology demonstrated DCIS (3, 33%), no residual cancer (5, 55%), and 1 patient was lost to followup (1, 11%). Interestingly, cancer patients who required reexcision were younger (p = 0.022), but breast density was not associated with reexcision. CONCLUSIONS: To our knowledge, this is the first report of MRI-guided bracket wire localization. Patients with MRI-detected lesions less than 4 cm had clear margins at first excision; larger MRI-detected lesions were more likely to have close/transected margins. Reexcision was often because of DCIS and was the only pathology found at reexcision, perhaps because MRI is more sensitive for detecting invasive carcinoma than DCIS.


Subject(s)
Breast Neoplasms/diagnosis , Breast Neoplasms/surgery , Carcinoma, Ductal, Breast/diagnosis , Carcinoma, Ductal, Breast/surgery , Magnetic Resonance Imaging/methods , Adult , Biopsy, Needle , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/pathology , Contrast Media , Female , Humans , Mammography , Middle Aged , Neoplasm Recurrence, Local , Preoperative Care , Reoperation/statistics & numerical data , Retrospective Studies , Sensitivity and Specificity , Statistics, Nonparametric , Treatment Outcome
7.
AJNR Am J Neuroradiol ; 26(3): 525-30, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15760860

ABSTRACT

BACKGROUND AND PURPOSE: Angioplasty and stent placement have been reported for the treatment of intracranial stenosis. This study was undertaken to assess the efficacy and long-term clinical outcome of angioplasty without stent placement for patients with symptomatic intracranial stenosis. METHODS: A retrospective study was done to evaluate 36 patients with 37 symptomatic atherosclerotic intracranial stenosis who underwent primary balloon angioplasty. All patients had symptoms despite medical therapy. Thirty-four patients were available for follow-up ranging from 6 to 128 months. Mean follow-up was 52.9 months. RESULTS: Mean pretreatment stenosis was 84.2% before angioplasty and 43.3% after angioplasty. The periprocedural death and stroke rate was 8.3% (two deaths and one minor stroke). Two patients had strokes in the territory of angioplasty at 2 and 37 months after angioplasty. The annual stroke rate in the territory appropriate to the site of angioplasty was 3.36%, and for those patients with a residual stenosis of > or =50% it was 4.5%. Patients with iatrogenic dissection (n=11) did not have transient ischemic attacks or strokes after treatment. CONCLUSION: Results of long-term follow-up suggest that intracranial angioplasty without stent placement reduces the risk of further stroke in symptomatic patients.


Subject(s)
Angioplasty, Balloon , Intracranial Arteriosclerosis/therapy , Adult , Aged , Aged, 80 and over , Aortic Dissection/epidemiology , Aortic Dissection/etiology , Angioplasty, Balloon/adverse effects , Cerebral Angiography , Female , Follow-Up Studies , Humans , Iatrogenic Disease/epidemiology , Incidence , Intracranial Arteriosclerosis/diagnostic imaging , Intracranial Arteriosclerosis/mortality , Male , Middle Aged , Retrospective Studies , Stroke/epidemiology , Treatment Outcome
8.
Neuroimage ; 24(2): 462-72, 2005 Jan 15.
Article in English | MEDLINE | ID: mdl-15627588

ABSTRACT

Load-dependent and practice-related changes in neocortical and cerebellar structures involved in verbal working memory (VWM) were investigated using functional MRI (fMRI) and a two alternative forced choice Sternberg paradigm. Using working memory loads ranging from 2 to 6 letters, regions exhibiting linear and quadratic trends in load-dependent activations were identified. Behaviorally, reaction time measurements revealed significant linear increases with increasing memory load, and significant decreases with increased task practice. Brain activations indicated a preponderance of linear load-dependent responses in both superior (lobule VI/Crus I) and inferior (lobule VIIB/VIIIA) cerebellar hemispheres, as well as in areas of neocortex including left precentral (BA 6), inferior frontal (BA 47), parahippocampal (BA 35), inferior parietal (BA 40), cingulate (BA 32), and right inferior and middle frontal (BA 46/47) regions. Fewer voxels exhibited quadratic without linear trends with the most prominent of these activations located in left inferior parietal (BA 40), precuneus, and parahippocampal regions. Analysis of load x session interactions revealed that right inferior cerebellar and left inferior parietal activations increased with practice, as did the correlations between activation in each region with reaction time, suggesting that changes in this cerebro-cerebellar network underlie practice-related increases in efficiency of VWM performance. These results replicate and extend our previous findings of fMRI activation in the cerebellum during VWM, and demonstrate predominately linear increases in cerebro-cerebellar activation with increasing memory load as well as changes in network function with increased task proficiency.


Subject(s)
Cerebellum/physiology , Learning/physiology , Memory/physiology , Speech , Telencephalon/physiology , Adult , Brain Mapping/methods , Cerebellum/anatomy & histology , Female , Functional Laterality , Humans , Magnetic Resonance Imaging/methods , Male , Telencephalon/anatomy & histology
9.
Radiology ; 234(1): 274-83, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15537839

ABSTRACT

PURPOSE: To compare the performance of radiologists and of a computer-aided detection (CAD) algorithm for pulmonary nodule detection on thin-section thoracic computed tomographic (CT) scans. MATERIALS AND METHODS: The study was approved by the institutional review board. The requirement of informed consent was waived. Twenty outpatients (age range, 15-91 years; mean, 64 years) were examined with chest CT (multi-detector row scanner, four detector rows, 1.25-mm section thickness, and 0.6-mm interval) for pulmonary nodules. Three radiologists independently analyzed CT scans, recorded the locus of each nodule candidate, and assigned each a confidence score. A CAD algorithm with parameters chosen by using cross validation was applied to the 20 scans. The reference standard was established by two experienced thoracic radiologists in consensus, with blind review of all nodule candidates and free search for additional nodules at a dedicated workstation for three-dimensional image analysis. True-positive (TP) and false-positive (FP) results and confidence levels were used to generate free-response receiver operating characteristic (ROC) plots. Double-reading performance was determined on the basis of TP detections by either reader. RESULTS: The 20 scans showed 195 noncalcified nodules with a diameter of 3 mm or more (reference reading). Area under the alternative free-response ROC curve was 0.54, 0.48, 0.55, and 0.36 for CAD and readers 1-3, respectively. Differences between reader 3 and CAD and between readers 2 and 3 were significant (P < .05); those between CAD and readers 1 and 2 were not significant. Mean sensitivity for individual readings was 50% (range, 41%-60%); double reading resulted in increase to 63% (range, 56%-67%). With CAD used at a threshold allowing only three FP detections per CT scan, mean sensitivity was increased to 76% (range, 73%-78%). CAD complemented individual readers by detecting additional nodules more effectively than did a second reader; CAD-reader weighted kappa values were significantly lower than reader-reader weighted kappa values (Wilcoxon rank sum test, P < .05). CONCLUSION: With CAD used at a level allowing only three FP detections per CT scan, sensitivity was substantially higher than with conventional double reading.


Subject(s)
Diagnosis, Computer-Assisted , Lung Neoplasms/diagnostic imaging , Tomography, X-Ray Computed , Adolescent , Adult , Aged , Aged, 80 and over , Algorithms , Female , Humans , Male , Middle Aged , Radiographic Image Interpretation, Computer-Assisted , Radiography, Thoracic , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity
10.
Arch Intern Med ; 164(22): 2415-9, 2004.
Article in English | MEDLINE | ID: mdl-15596630

ABSTRACT

BACKGROUND: Self-referred imaging is one of the latest health care services to be marketed directly to consumers. Most aspects of these services are unregulated, and little is known about the messages in advertising used to attract potential consumers. We conducted a detailed analysis of print advertisements and informational brochures for self-referred imaging with respect to themes, content, accuracy, and emotional valence. METHODS: Forty print advertisements from US newspapers around the country and 20 informational brochures were analyzed by 2 independent raters according to 7 major themes: health care technology; emotion, empowerment, and assurance; incentives; limited supporting evidence; popular appeal; statistics; and images. The Fisher exact test was used to identify significant differences in information content. RESULTS: Both the advertisements and the brochures emphasized health care and technology information and provided assurances of good health and incentives to self-refer. These materials also encouraged consumers to seek further information from company resources; virtually none referred to noncomplying sources of information or to the risks of having a scan. Images of people commonly portrayed European Americans. We found statistical differences between newspaper advertisements and mailed brochures for references to "prevalence of disease" (P<.001), "death" (P<.003), and "radiation" (P<.001). Statements lacking clear scientific evidence were identified in 38% of the advertisements (n = 15) and 25% of the brochures (n = 5). CONCLUSIONS: Direct-to-consumer marketing of self-referred imaging services, in both print advertisements and informational brochures, fails to provide prospective consumers with comprehensive balanced information vital to informed autonomous decision making. Professional guidelines and oversight for advertising and promotion of these services are needed.


Subject(s)
Advertising/trends , Decision Making , Magnetic Resonance Imaging , Patients/psychology , Physician Self-Referral/trends , Tomography, X-Ray Computed , United States
11.
J Comput Assist Tomogr ; 28(3): 318-26, 2004.
Article in English | MEDLINE | ID: mdl-15100534

ABSTRACT

OBJECTIVE: : To determine the feasibility of a computer-aided detection (CAD) algorithm as the "first reader" in computed tomography colonography (CTC). METHODS: : In phase 1 of a 2-part blind trial, we measured the performance of 3 radiologists reading 41 CTC studies without CAD. In phase 2, readers interpreted the same cases using a CAD list of 30 potential polyps. RESULTS: : Unassisted readers detected, on average, 63% of polyps > or =10 mm in diameter. Using CAD, the sensitivity was 74% (not statistically different). Per-patient analysis showed a trend toward increased sensitivity for polyps > or =10 mm in diameter, from 73% to 90% with CAD (not significant) without decreasing specificity. Computer-aided detection significantly decreased interobserver variability (P = 0.017). Average time to detection of the first polyp decreased significantly with CAD, whereas total reading case reading time was unchanged. CONCLUSION: : Computer-aided detection as a first reader in CTC was associated with similar per-polyp and per-patient detection sensitivity to unassisted reading. Computer-aided detection decreased interobserver variability and reduced the time required to detect the first polyp.


Subject(s)
Colonic Polyps/diagnostic imaging , Colonography, Computed Tomographic , Adult , Aged , Aged, 80 and over , Colonography, Computed Tomographic/statistics & numerical data , Feasibility Studies , Female , Humans , Male , Middle Aged , Observer Variation , Sensitivity and Specificity , Single-Blind Method , Time Factors
12.
Med Phys ; 30(10): 2572-83, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14596293

ABSTRACT

Two-dimensional intensity-based methods for the segmentation of blood vessels from computed-tomography-angiography data often result in spurious segments that originate from other objects whose intensity distributions overlap with those of the vessels. When segmented images include spurious segments, additional methods are required to select segments that belong to the target vessels. We describe a method that allows experts to select vessel segments from sequences of segmented images with little effort. Our method uses ellipse-overlap criteria to differentiate between segments that belong to different objects and are separated in plane but are connected in the through-plane direction. To validate our method, we used it to extract vessel regions from volumes that were segmented via analysis of isolabel-contour maps, and showed that the difference between the results of our method and manually-edited results was within inter-expert variability. Although the total editing duration for our method, which included user-interaction and computer processing, exceeded that of manual editing, the extent of user interaction required for our method was about a fifth of that required for manual editing.


Subject(s)
Angiography/methods , Image Processing, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , Aneurysm/diagnosis , Aorta/pathology , Humans , Models, Theoretical , Observer Variation , Software
13.
Med Phys ; 30(10): 2663-74, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14596303

ABSTRACT

Multislice helical CT offers several retrospective choices of longitudinal (z) resolution at a given detector collimation setting. We sought to determine the effect of z resolution on the performance of a computer-aided colonic polyp detector, since a human reader and a computer-aided polyp detector may have optimal performances at different z resolutions. We ran a computer-aided polyp detection algorithm on phantom data sets as well as data obtained from a single patient. All data were reconstructed at various slice thicknesses ranging from 1.25 to 10 mm. We studied the performance of the detector at various ranges of polyp sizes using free-response receiver-operating characteristic analyses. We also studied contrast-to-noise ratios (CNR) as a function of slice thickness and polyp size. For the phantom data, reducing the slice thickness from 5 to 1.25 mm improves sensitivity from 84.5% to 98.3% (all polyps), from 61.4% to 95.5% (polyps in the range [0, 5) mm) and from 97.7% to 100% (polyps in the range [5, 10) mm) at a false positive rate of 20 per data set. For polyps larger than 10 mm, there is no significant improvement in detection sensitivity when slice thickness is reduced. CNRs showed expected behavior with slice thickness and polyp size, but in all cases remained high (> 4). The results for the patient data followed similar patterns to that of the phantom case. Thus we conclude that for this detector, the optimal slice thickness is dependent upon the size of the smallest polyps to be detected. For detection of polyps 10 mm and larger, reconstruction of 5 mm sections may be sufficient. Further study is required to generalize these results to a broader population of patients scanned on different scanners.


Subject(s)
Colon/pathology , Colonography, Computed Tomographic/methods , Image Processing, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , Female , Humans , Middle Aged , Models, Statistical , Models, Theoretical , Phantoms, Imaging , ROC Curve , Software
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