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1.
Eur Radiol ; 32(1): 533-541, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34268596

RESUMO

OBJECTIVES: To compare the diagnostic accuracy of generalist radiologists working in a community setting against abdominal radiologists working in an academic setting for the interpretation of MR when diagnosing acute appendicitis among emergency department patients. METHODS: This observational study examined MR image interpretation (non-contrast MR with diffusion-weighted imaging and intravenous contrast-enhanced MR) from a prospectively enrolled cohort at an academic hospital over 18 months. Eligible patients had an abdominopelvic CT ordered to evaluate for appendicitis and were > 11 years old. The reference standard was a combination of surgery and pathology results, phone follow-up, and chart review. Six radiologists blinded to clinical information, three each from community and academic practices, independently interpreted MR and CT images in random order. We calculated test characteristics for both individual and group (consensus) diagnostic accuracy then performed Chi-square tests to identify any differences between the subgroups. RESULTS: Analysis included 198 patients (114 women) with a mean age of 31.6 years and an appendicitis prevalence of 32.3%. For generalist radiologists, the sensitivity and specificity (95% confidence interval) were 93.8% (84.6-98.0%) and 88.8% (82.2-93.2%) for MR and 96.9% (88.7-99.8%) and 91.8% (85.8-95.5%) for CT. For fellowship-trained radiologists, the sensitivity and specificity were 96.9% (88.2-99.5%) and 89.6% (82.8-94%) for MR and 98.4% (90.5-99.9%) and 93.3% (87.3-96.7%) for CT. No statistically significant differences were detected between radiologist groups (p = 1.0, p = 0.53, respectively) or when comparing MR to CT (p = 0.21, p = 0.17, respectively). CONCLUSIONS: MR is a reliable, radiation-free imaging alternative to CT for the evaluation of appendicitis in community-based generalist radiology practices. KEY POINTS: • There was no significant difference in MR image interpretation accuracy between generalist and abdominal fellowship-trained radiologists when evaluating sensitivity (p = 1.0) and specificity (p = 0.53). • There was no significant difference in accuracy comparing MR to CT imaging for diagnosing appendicitis for either sensitivity (p = 0.21) or specificity (p = 0.17). • With experience, generalist radiologists enhanced their MR interpretation accuracy as demonstrated by improved interpretation sensitivity (OR 2.89 CI 1.44-5.77, p = 0.003) and decreased mean interpretation time (5 to 3.89 min).


Assuntos
Apendicite , Adulto , Apendicite/diagnóstico por imagem , Criança , Bolsas de Estudo , Feminino , Humanos , Radiologistas , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
2.
J Comput Assist Tomogr ; 45(4): 495-499, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34270477

RESUMO

ABSTRACT: This article will review critical components for the successful completion of a multi-institution, multiauthor collaborative paper. Best practices for the creation and publication of a collaborative paper will be addressed.


Assuntos
Autoria , Publicações Periódicas como Assunto , Editoração , Radiologia , Redação , Centros Médicos Acadêmicos , Comportamento Cooperativo , Humanos
3.
J Comput Assist Tomogr ; 45(4): 637-642, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34176877

RESUMO

OBJECTIVE: To demonstrate the utility of deep learning enhancement (DLE) to achieve diagnostic quality low-dose positron emission tomography (PET)/magnetic resonance (MR) imaging. METHODS: Twenty subjects with known Crohn disease underwent simultaneous PET/MR imaging after intravenous administration of approximately 185 MBq of 18F-fluorodeoxyglucose (FDG). Five image sets were generated: (1) standard-of-care (reference), (2) low-dose (ie, using 20% of PET counts), (3) DLE-enhanced low-dose using PET data as input, (4) DLE-enhanced low-dose using PET and MR data as input, and (5) DLE-enhanced using no PET data input. Image sets were evaluated by both quantitative metrics and qualitatively by expert readers. RESULTS: Although low-dose images (series 2) and images with no PET data input (series 5) were nondiagnostic, DLE of the low-dose images (series 3 and 4) achieved diagnostic quality images that scored more favorably than reference (series 1), both qualitatively and quantitatively. CONCLUSIONS: Deep learning enhancement has the potential to enable a 90% reduction of radiotracer while achieving diagnostic quality images.


Assuntos
Aprendizado Profundo , Fluordesoxiglucose F18 , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Adulto Jovem
4.
AJR Am J Roentgenol ; 214(3): 694-700, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31770022

RESUMO

OBJECTIVE. The purpose of this study was to evaluate the International Ovarian Tumor Analysis (IOTA) simple rules and the Society of Radiologists in Ultrasound (SRU) guidelines for detecting ovarian malignancy in a general population of women presenting to radiology departments with adnexal cystic lesions. MATERIALS AND METHODS. A retrospective multicenter study of ultrasound-detected adnexal cystic lesions with appropriate follow-up was conducted. Lesions were classified into benign, indeterminate, or malignant categories according to criteria based on the IOTA simple rules and the SRU guidelines. The prevalence of nonneoplastic cysts, neoplasms, and malignant tumors was calculated. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated, and ROC analysis for the diagnosis of malignancy was performed. RESULTS. A total of 697 women with 764 cystic lesions were included; 85.2% (651/764) of the lesions were nonneoplastic, 12.2% (93/764) were benign neoplasms, and 2.6% (20/764) were malignant neoplasms. Nearly all malignancies were classified into indeterminate and malignant categories. The prevalence of malignancy in the indeterminate category was 4.8% (7/145) (SRU) to 10.7% (7/65) (IOTA) and in the malignant category was 18.1% (13/72) (SRU) to 34.3% (12/35) (IOTA). Only one malignancy was misclassified as benign by the IOTA simple rules. The sensitivity of the IOTA simple rules for malignancy was 90.0%; specificity, 96.5%; PPV, 29.0%; NPV, 99.8%; and accuracy, 96.4%. The corresponding values for the SRU guidelines were 100%, 89.6%, 14.9%, 100%, and 89.8%. In ROC analysis, the IOTA simple rules were slightly more accurate than the SRU guidelines (AUC, 0.9805 versus 0.9713; p = 0.0003). CONCLUSION. Both imaging characterization methods were sensitive for identifying ovarian malignancies, but the PPV was low among women presenting to radiology departments, and the indeterminate classification harbored one-third of the total malignancies. Exploration of varied clinical settings and inclusion of secondary tests may help to refine these systems.


Assuntos
Doenças dos Anexos/diagnóstico por imagem , Cistos/diagnóstico por imagem , Neoplasias Ovarianas/diagnóstico por imagem , Guias de Prática Clínica como Assunto , Ultrassonografia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
J Vis ; 20(8): 16, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32790849

RESUMO

A sizeable body of work has demonstrated that participants have the capacity to show substantial increases in performance on perceptual tasks given appropriate practice. This has resulted in significant interest in the use of such perceptual learning techniques to positively impact performance in real-world domains where the extraction of perceptual information in the service of guiding decisions is at a premium. Radiological training is one clear example of such a domain. Here we examine a number of basic science questions related to the use of perceptual learning techniques in the context of a radiology-inspired task. On each trial of this task, participants were presented with a single axial slice from a CT image of the abdomen. They were then asked to indicate whether or not the image was consistent with appendicitis. We first demonstrate that, although the task differs in many ways from standard radiological practice, it nonetheless makes use of expert knowledge, as trained radiologists who underwent the task showed high (near ceiling) levels of performance. Then, in a series of four studies we show that (1) performance on this task does improve significantly over a reasonably short period of training (on the scale of a few hours); (2) the learning transfers to previously unseen images and to untrained image orientations; (3) purely correct/incorrect feedback produces weak learning compared to more informative feedback where the spatial position of the appendix is indicated in each image; and (4) there was little benefit seen from purposefully structuring the learning experience by starting with easier images and then moving on to more difficulty images (as compared to simply presenting all images in a random order). The implications for these various findings with respect to the use of perceptual learning techniques as part of radiological training are then discussed.


Assuntos
Apendicite/diagnóstico por imagem , Competência Clínica/normas , Aprendizagem/fisiologia , Radiologistas/normas , Tomografia Computadorizada por Raios X , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Orientação , Transferência de Experiência
6.
J Magn Reson Imaging ; 50(5): 1651-1658, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30892788

RESUMO

BACKGROUND: Computed tomography (CT) is commonly used in the Emergency Department (ED) to evaluate patients with abdominal pain, but exposes them to ionizing radiation, a possible carcinogen. MRI does not utilize ionizing radiation and may be an alternative. PURPOSE: To compare the sensitivity of MRI and CT for acute abdominopelvic ED diagnoses. STUDY TYPE: Prospective, observational cohort. POPULATION: ED patients ≥12 years old and undergoing CT for possible appendicitis. FIELD STRENGTH/SEQUENCE: 1.5 T MRI, including T1 -weighted, T2 -weighted, and diffusion-weighted imaging sequences. ASSESSMENT: Three radiologists independently interpreted each MRI and CT image set separately and blindly, using a standard case report form. Assessments included likelihood of appendicitis, presence of an alternative diagnosis, and likelihood that the alternative diagnosis was causing the patient's symptoms. An expert panel utilized chart review and follow-up phone interviews to determine all final diagnoses. Times to complete image acquisition and image interpretation were also calculated. STATISTICAL TESTS: Sensitivity was calculated for each radiologist and by consensus (≥2 radiologists in agreement) and are reported as point estimates with 95% confidence intervals. Two-sided hypothesis tests comparing the sensitivities of the three image types were conducted using Pearson's chi-squared test with the traditional significance level of P = 0.05. RESULTS: There were 15 different acute diagnoses identified on the CT/MR images of 113 patients. Using individual radiologist interpretations, the sensitivities of noncontrast-enhanced MRI (NCE-MR), contrast-enhanced MR (CE-MR), and CT for any acute diagnosis were 77.0% (72.6-81.4%), 84.2% (80.4-88.0%), and 88.7% (85.5-92.1%). Sensitivity of consensus reads was 82.0% (74.9-88.9%), 87.1% (81.0-93.2%), 92.2% (87.3-97.1%), respectively. There was no difference in sensitivities between CE-MR and CT by individual (P = 0.096) or consensus interpretations (P = 0.281), although NCE-MR was inferior to CT in both modes of analysis (P < 0.001, P = 0.031, respectively). DATA CONCLUSION: The sensitivity of CE-MR was similar to CT when diagnosing acute, nontraumatic abdominopelvic pathology in our cohort. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1651-1658.


Assuntos
Dor Abdominal/diagnóstico por imagem , Apendicite/diagnóstico por imagem , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Dor Abdominal/etiologia , Adolescente , Adulto , Apendicite/etiologia , Medicina de Emergência/métodos , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto Jovem
7.
Radiology ; 288(2): 467-475, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29688158

RESUMO

Purpose To compare the accuracy of magnetic resonance (MR) imaging with that of computed tomography (CT) for the diagnosis of acute appendicitis in emergency department (ED) patients. Materials and Methods This was an institutional review board-approved, prospective, observational study of ED patients at an academic medical center (February 2012 to August 2014). Eligible patients were nonpregnant and 12- year-old or older patients in whom a CT study had been ordered for evaluation for appendicitis. After informed consent was obtained, CT and MR imaging (with non-contrast material-enhanced, diffusion-weighted, and intravenous contrast-enhanced sequences) were performed in tandem, and the images were subsequently retrospectively interpreted in random order by three abdominal radiologists who were blinded to the patients' clinical outcomes. Likelihood of appendicitis was rated on a five-point scale for both CT and MR imaging. A composite reference standard of surgical and histopathologic results and clinical follow-up was used, arbitrated by an expert panel of three investigators. Test characteristics were calculated and reported as point estimates with 95% confidence intervals (CIs). Results Analysis included images of 198 patients (114 women [58%]; mean age, 31.6 years ± 14.2 [range, 12-81 years]; prevalence of appendicitis, 32.3%). The sensitivity and specificity were 96.9% (95% CI: 88.2%, 99.5%) and 81.3% (95% CI: 73.5%, 87.3%) for MR imaging and 98.4% (95% CI: 90.5%, 99.9%) and 89.6% (95% CI: 82.8%, 94.0%) for CT, respectively, when a cutoff point of 3 or higher was used. The positive and negative likelihood ratios were 5.2 (95% CI: 3.7, 7.7) and 0.04 (95% CI: 0, 0.11) for MR imaging and 9.4 (95% CI: 5.9, 16.4) and 0.02 (95% CI: 0.00, 0.06) for CT, respectively. Receiver operating characteristic curve analysis demonstrated that the optimal cutoff point to maximize accuracy was 4 or higher, at which point there was no difference between MR imaging and CT. Conclusion The diagnostic accuracy of MR imaging was similar to that of CT for the diagnosis of acute appendicitis.


Assuntos
Apendicite/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Apêndice/diagnóstico por imagem , Criança , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
8.
Radiology ; 287(3): 1041-1049, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29480762

RESUMO

Purpose To assess the prevalence of indeterminate adnexal cysts in women presenting to academic medical centers for pelvic ultrasonography (US), determine the incidence of malignancy, and identify cyst and patient characteristics that are predictive of malignancy. Materials and Methods A multicenter study of US-detected adnexal cysts with appropriate follow-up (surgical pathologic examination, imaging and/or clinical examination) was conducted from January 2008 to June 2012. Indeterminate cysts were classified as category 1 (typical benign appearing cysts >5 cm) or category 2 (cysts with avascular solid components) on the basis of a combination of definitions in the existing literature. The incidence of neoplasms and malignant tumors was calculated. Patient and cyst characteristics associated with neoplasm and malignant tumors were evaluated with the χ2 test or Fisher exact test for categorical variables and the t test for continuous variables. A backward stepwise logistic regression model was performed for two outcomes: (a) the presence of any neoplasm (benign or malignant) and (b) the presence of a malignant tumor. Results There were 1637 women with an adnexal cyst at US; 391 (mean age = 41.8 years ± 13.5.1; range = 17-91 years) had an indeterminate adnexal cyst at US. The prevalence of indeterminate adnexal cysts was 23.9% (391 of 1637; 95% confidence interval [CI]: 0.22, 0.26). Three hundred three indeterminate cysts in 280 women (mean age = 42.9 years ± 14.1; range = 17-88 years) had adequate follow-up. The incidence of ovarian neoplasms (benign and malignant) was 24.8% (75 of 303 cysts; 95% CI: 0.20, 0.30), and the incidence of malignant tumors was 3.6% (11 of 303 cysts; 95% CI: 0.02, 0.06). The proportion of ovarian neoplasms differed between category 1 and category 2 cysts (17.5% [25 of 143 cysts; 95% CI: 0.12, 0.25] vs 31.3% [50 of 160 cysts; 95% CI: 0.24, 0.39], respectively; P = .001). The proportion of malignant tumors differed between categories 1 and 2 cysts (0% [0 of 143 cysts] vs 6.9% [11 of 160 cysts; 95% CI: 0.03, 0.12]; P < .001). The presence of an avascular nodular component was a significant predictor of malignancy at stepwise logistic regression analysis (odds ratio = 2.83; P ≤ .0001; 95% CI: 1.69, 4.70). Conclusion The presence of an avascular nodular component was the most significant predictor of the presence of malignancy in indeterminate adnexal cysts. The risk of malignancy is higher with category 2 cysts than with category 1 cysts. © RSNA, 2018.


Assuntos
Doenças dos Anexos/diagnóstico por imagem , Cistos Ovarianos/diagnóstico por imagem , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/epidemiologia , Ultrassonografia/métodos , Anexos Uterinos/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Incidência , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Adulto Jovem
9.
Radiology ; 285(2): 650-659, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28727500

RESUMO

Purpose To evaluate the performance of the 2010 Society of Radiologists in Ultrasound (SRU) consensus guidelines in the risk stratification of symptomatic and asymptomatic adnexal cysts. Materials and Methods An institutional review board-approved retrospective review was performed, including adnexal cysts detected with ultrasonography (US) with surgical diagnosis or at least 2 years of imaging or clinical follow-up, from January to June 2011. SRU management recommendations were scored as 0, no follow-up; 1, US follow-up; 2, magnetic resonance (MR) imaging follow-up; and 3, surgical evaluation. Distribution of outcomes (nonneoplastic cyst, benign neoplasm, malignant neoplasm) was compared in each rating group by using the Cochran-Armitage trend test. Where SRU guidelines allow more than one management option, they were classified as being interpreted in either a "surgically focused" environment, with limited MR imaging availability, or an "MR-capable" center, where MR imaging is selected whenever it is an option. Predictors of neoplasms and malignancy were evaluated by using multivariate logistic regression. Results A total of 570 cysts in 500 women aged 18-90 years (mean, 42 years) were included. There were 475 (83.3%) nonneoplastic cysts, 77 (13.5%) benign neoplasms, and 18 (3.2%) malignant neoplasms. Of the 500 women, 161 (32.2%) were asymptomatic. In the surgically focused interpretation of guidelines, proportions of any neoplasm and malignant neoplasm, respectively, were 1% and 0% in SRU 0, 17% and 1% in SRU 1, 48% and 0% in SRU 2, and 48% and 16% in SRU 3 (P < .0001 for both trends). In the interpretation of SRU guidelines with MR imaging when it was an option, proportions of any neoplasm and malignant neoplasm, respectively, were 1% and 0% in SRU 0, 17% and 1% in SRU 1, 38% and 5% in SRU 2, and 81% and 52% in SRU 3 (P < .0001, both trends) and 82 (89.1%) fewer benign cysts would have gone directly to surgical evaluation. In multivariate regression, SRU rating predicted both any neoplasm (odds ratio, 2.58; P < .0001) and malignant neoplasm (odds ratio, 4.94; P = .005). Conclusion SRU consensus guidelines effectively stratified the risk of neoplasia and malignancy. Selecting MR imaging when it is an option in the guidelines would have reduced the number of benign cysts sent for surgical evaluation. © RSNA, 2017.


Assuntos
Doenças dos Anexos , Cistos , Imageamento por Ressonância Magnética/métodos , Neoplasias , Ultrassonografia/métodos , Doenças dos Anexos/diagnóstico por imagem , Doenças dos Anexos/epidemiologia , Doenças dos Anexos/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cistos/diagnóstico por imagem , Cistos/epidemiologia , Cistos/terapia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias/diagnóstico por imagem , Neoplasias/epidemiologia , Neoplasias/terapia , Guias de Prática Clínica como Assunto , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
11.
AJR Am J Roentgenol ; 208(6): 1244-1248, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28753031

RESUMO

OBJECTIVE: We assessed the initial clinical performance and third-party reimbursement rates of supplementary computer-aided detection (CAD) at CT colonography (CTC) for detecting colorectal polyps 6 mm or larger in routine clinical practice. MATERIALS AND METHODS: We retrospectively assessed the prospective clinical performance of a U.S. Food and Drug Administration-approved CAD system in second-reader mode in 347 consecutive adults (mean age, 57.6 years; 205 women, 142 men) undergoing CTC evaluation over a 5-month period. The reference standard consisted of the prospective interpretation by experienced CTC radiologists combined with subsequent optical colonoscopy (OC), if performed. We also assessed third-party reimbursement for CAD for studies performed over an 18-month period. RESULTS: In all, 69 patients (mean [± SD] age, 59.0 ± 7.7 years; 32 men, 37 women) had 129 polyps ≥ 6 mm. Per-patient CAD sensitivity was 91.3% (63 of 69). Per-polyp CAD-alone sensitivity was 88.4% (114 of 129), including 88.3% (83 of 94) for 6- to 9-mm polyps and 88.6% (31 of 35) for polyps 10 mm or larger. On retrospective review, three additional polyps 6 mm or larger were seen at OC and marked by CAD but dismissed as CAD false-positives at CTC. The mean number of false-positive CAD marks was 4.4 ± 3.1 per series. Of 1225 CTC cases reviewed for reimbursement, 31.0% of the total charges for CAD interpretation had been recovered from a variety of third-party payers. CONCLUSION: In our routine clinical practice, CAD showed good sensitivity for detecting colorectal polyps 6 mm or larger, with an acceptable number of false-positive marks. Importantly, CAD is already being reimbursed by some third-party payers in our clinical CTC practice.


Assuntos
Colonografia Tomográfica Computadorizada/economia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/economia , Reembolso de Seguro de Saúde/economia , Pólipos Intestinais/diagnóstico por imagem , Pólipos Intestinais/economia , Colonografia Tomográfica Computadorizada/estatística & dados numéricos , Feminino , Humanos , Reembolso de Seguro de Saúde/estatística & dados numéricos , Aprendizado de Máquina/economia , Aprendizado de Máquina/estatística & dados numéricos , Masculino , Interpretação de Imagem Radiográfica Assistida por Computador/estatística & dados numéricos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos/epidemiologia
12.
AJR Am J Roentgenol ; 209(4): 911-919, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28796552

RESUMO

OBJECTIVE: Appendicitis is frequently diagnosed in the emergency department, most commonly using CT. The purpose of this study was to compare the diagnostic accuracy of contrast-enhanced MRI with that of contrast-enhanced CT for the diagnosis of appendicitis in adolescents when interpreted by abdominal radiologists and pediatric radiologists. SUBJECTS AND METHODS: Our study included a prospectively enrolled cohort of 48 patients (12-20 years old) with nontraumatic abdominal pain who underwent CT and MRI. Fellowship-trained abdominal and pediatric radiologists reviewed all CT and MRI studies in randomized order, blinded to patient outcome. Likelihood for appendicitis was rated on a 5-point scale (1, definitely not appendicitis; 5, definitely appendicitis) for CT, the unenhanced portion of the MRI, and the entire contrast-enhanced MRI study. ROC curves were generated and AUC compared for each scan type for all six readers and then stratified by radiologist type. Image test characteristics, interrater reliability, and reading times were compared. RESULTS: Sensitivity and specificity were 85.9% (95% CI, 76.2-92.7%) and 93.8% (95% CI, 89.7-96.7%) for unenhanced MRI, 93.6% (95% CI, 85.6-97.9%) and 94.3% (95% CI, 90.2-97%) for contrast-enhanced MRI, and 93.6% (95% CI, 85.6-97.9%) and 94.3% (95% CI, 90.2-97%) for CT. No difference was found in the diagnostic accuracy or interpretation time when comparing abdominal radiologists to pediatric radiologists (CT, 3.0 min vs 2.8 min; contrast-enhanced MRI, 2.4 min vs 1.8 min; unenhanced MRI, 1.5 min vs 2.3 min). Substantial agreement between abdominal and pediatric radiologists was seen for all methods (κ = 0.72-0.83). CONCLUSION: The diagnostic accuracy of MRI to diagnose appendicitis was very similar to CT. No statistically significant difference in accuracy was observed between imaging modality or radiologist subspecialty.


Assuntos
Apendicite/diagnóstico por imagem , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Doença Aguda , Adolescente , Criança , Feminino , Humanos , Masculino , Estudos Prospectivos , Radiografia Abdominal/métodos , Reprodutibilidade dos Testes , Adulto Jovem
14.
AJR Am J Roentgenol ; 206(6): 1202-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27010251

RESUMO

OBJECTIVE: The purpose of this study is to objectively and subjectively compare nonionic iohexol and ionic diatrizoate iodinated oral contrast agents as part of a cathartic bowel regimen within the same CT colonography (CTC) cohort, with otherwise identical preparations. MATERIALS AND METHODS: In this retrospective study, 46 adults with no symptoms (mean age, 59.4 years; 26 men and 20 women) returning for follow-up CTC over a 9-month interval underwent the same bowel preparation with the exception of 75 mL of iohexol 350 in place of 60 mL of diatrizoate. All other preparation components (bisacodyl, magnesium citrate, and 2% barium) remained constant. Objective volumetric analysis of residual colonic fluid volume and fluid attenuation was performed. Additionally, two radiologists experienced with CTC who were blinded to the specific bowel preparation scored each of six colonic segments for adherent residual solid stool using a previously validated 4-point scale (0 for no stool; 1-3 for increasing residual stool). A paired t test was used for comparison of the cohorts. RESULTS: No clear clinically meaningful difference was found between the two preparations on overall objective or subjective evaluation. The mean (± SD) residual fluid volume was 173 ± 126 mL with the iohexol preparation and 130 ± 79 mL with the diatrizoate preparation (p = 0.02). The mean total colonic stool score was 2.5 (0.42/segment) with iohexol and 2.3 (0.38/segment) with diatrizoate (p = 0.69). The mean fluid attenuation was higher with iohexol (849 ± 270 HU) compared with diatrizoate (732 ± 168 HU) (p = 0.03). CONCLUSION: On the basis of this direct intrapatient comparison, we found that oral iohexol is a suitable alternative to diatrizoate for fluid tagging as part of a cathartic bowel preparation at CTC. Because this nonionic tagging agent is more palatable, less expensive, and likely safer than ionic diatrizoate, our CTC program now uses iohexol as the standard recommended regimen.


Assuntos
Catárticos , Colonografia Tomográfica Computadorizada , Meios de Contraste , Diatrizoato , Iohexol , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
15.
AJR Am J Roentgenol ; 207(6): 1334-1339, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27657546

RESUMO

OBJECTIVE: Small pulmonary nodules are often difficult to identify during thoracoscopic resection, and preoperative CT-guided localization performed using either hookwire placement or methylene blue injection can be helpful. The purpose of this study is to compare the localization success and complication rates of these two techniques. MATERIALS AND METHODS: One hundred two consecutive patients who underwent a total of 109 localization procedures performed with CT fluoroscopic guidance were analyzed. The procedures included 52 hookwire insertions and 57 methylene blue injections. The localization success and complication rates associated with the two groups were compared. RESULTS: All nodules in both groups were identified intraoperatively, except for those in two patients in the hookwire group who did not proceed to undergo same-day surgery, including one with a massive systemic air embolus that resulted in death. Hookwires were dislodged in seven of 52 cases (13%), but the surgeons were still able to locate the nodules through visualization of the parenchymal puncture sites. The total number of complications was higher in the hookwire insertion group than in the methylene blue injection group, but this trend was not statistically significant, with all types of complications occurring in 28 cases (54%) versus 26 cases (46%) (p = 0.45), major complications noted in four cases (8%) versus one case (2%) (p = 0.19), pneumothorax observed in 20 cases (38%) versus 14 cases (25%) (p = 0.15), and perilesional hemorrhage occurring in six cases (12%) versus two cases (4%) (p = 0.15), respectively. CONCLUSION: The present study suggests that methylene blue injection and hookwire insertion are statistically equivalent for preoperative pulmonary nodule localization; however, seven of 52 hookwires dislodged, and trends toward more frequent and severe complications were noted in the hookwire insertion group.


Assuntos
Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Azul de Metileno , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/patologia , Coloração e Rotulagem/métodos , Feminino , Humanos , Biópsia Guiada por Imagem/métodos , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Nódulo Pulmonar Solitário/cirurgia , Cirurgia Assistida por Computador/métodos , Toracoscopia/métodos , Tomografia Computadorizada por Raios X/métodos
17.
J Magn Reson Imaging ; 41(1): 1-12, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25288098

RESUMO

Müllerian duct anomalies (MDA) occur due to abnormal development of the uterus, cervix, and vagina, many times affecting a woman's ability to conceive and carry a pregnancy to term. The spectrum of possible abnormalities are related to the development of two separate Müllerian systems, which then fuse and subsequently undergo degeneration of the fused segments. This multiphasic development explains the multiple variations within the scheme of MDA classification. The purpose of this article is to review the embryologic development of the Müllerian ducts, relate the development to the most commonly used classification system, and review the magnetic resonance imaging (MRI) assessment of Müllerian duct anomalies. A brief review of the treatment options, as they relate to the imaging diagnosis, will be provided as well.


Assuntos
Colo do Útero/patologia , Desenvolvimento Embrionário/fisiologia , Imageamento por Ressonância Magnética/métodos , Ductos Paramesonéfricos/anormalidades , Útero/patologia , Vagina/patologia , Feminino , Humanos
18.
AJR Am J Roentgenol ; 205(5): W556-64, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26496578

RESUMO

OBJECTIVE: The objective of our study was to determine the predictive value of preoperative pelvic MRI and serum cancer antigen-125 (CA-125) evaluation in selecting women with grade 1 endometrial cancer for lymphadenectomy as part of the cancer staging operation. MATERIALS AND METHODS: A new preoperative clinical protocol including MRI and CA-125 evaluation was adopted at our institution in patients with grade 1 endometrioid adenocarcinoma. Lymphadenectomy was considered as part of the surgical staging operation if there was an elevated CA-125 value or a positive MRI finding (≥ 50% myometrial invasion, cervical invasion, abnormal lymph nodes, extrauterine disease, or tumor index ≥ 36 cm). From January 2012 through May 2013, a retrospective analysis was performed of 100 women who underwent preoperative MRI and CA-125 evaluation; we refer to this cohort as the "preoperative study cohort." The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated using final surgical pathology and CA-125 results as the reference standard. The rate of metastatic lymph nodes in the preoperative study cohort was determined. From May 2009 through January 2011, a retrospective analysis of a cohort who did not undergo preoperative MRI and CA-125 evaluation was undertaken to compare lymphadenectomy and lymph node metastasis rates before and after implementation of the new protocol; we refer to this cohort as the "historical cohort." RESULTS: The new clinical protocol had sensitivity of 94%, specificity of 91%, PPV of 84%, and NPV of 97%. When histologic grade alone was considered, positive lymph node rates in the preoperative study cohort was 4.0% versus 4.2% in the historical cohort. In the preoperative study cohort, the lymph node metastasis rate increased to 11.1% with a positive MRI finding or elevated CA-125 value. CONCLUSION: Preoperative MRI and CA-125 evaluation identified women for lymphadenectomy with a high NPV.


Assuntos
Adenocarcinoma/sangue , Adenocarcinoma/patologia , Antígeno Ca-125/sangue , Neoplasias do Endométrio/sangue , Neoplasias do Endométrio/patologia , Metástase Linfática/diagnóstico , Imageamento por Ressonância Magnética/métodos , Idoso , Biomarcadores Tumorais/sangue , Biópsia , Protocolos Clínicos , Feminino , Humanos , Excisão de Linfonodo , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
19.
AJR Am J Roentgenol ; 203(6): W623-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25415727

RESUMO

OBJECTIVE: The purpose of this study was to compare total colonic gas volume and segmental luminal distention according to patient position on CT colonography (CTC), as well as to determine which two views should constitute the routine protocol. MATERIALS AND METHODS: Volumetric analysis was retrospectively performed on CTC examinations from 146 adults (mean age, 59.2 years; 81 men and 65 women; mean body mass index [BMI], 30.9) for whom supine, prone, and right lateral decubitus series were sequentially obtained using continuous low-pressure CO2 insufflation. Total colonic gas volumes were assessed using a novel automated volumetric tool. In addition, two radiologists scored distention by segment using a 4-point scale (4=optimal; 3=adequate; 2=inadequate; 1=collapsed). RESULTS: Mean (±SD) colonic gas volumes for supine, prone, and decubitus positioning were 1617±567, 1441±505, and 1901±627, respectively (p<0.001). Colonic volume was highest on the right lateral decubitus series in 73.3% (107/146) and lowest in 6.2% (9/146) of cases, whereas the prone series was highest in 0.7% (1/146) and lowest in 73.3% (107/146) of cases. Overall mean segmental reader scores and percentages of inadequate or collapsed for supine, prone, and decubitus positions were 3.48, 3.33, and 3.71 and 10.4%, 12.1%, and 4.2%, respectively (p<0.001). The only mean segmental scores below 3.0 were the sigmoid colon on supine (2.68) and prone (2.58) series, compared with 3.23 on decubitus series (p<0.001). Improvement in distention in both decubitus and supine positions over the prone position increased further with increasing BMI (p<0.001). CONCLUSION: The right lateral decubitus position consistently yields the best colonic distention at CTC and significantly improves evaluation of the sigmoid colon. Prone distention was the worst, particularly as BMI increased. Routine supine and decubitus positioning should be considered for standard CTC protocols, particularly in obese individuals. Automated volumetric analysis provides for rapid objective assessment of colonic distention.


Assuntos
Dióxido de Carbono , Colo/diagnóstico por imagem , Colonografia Tomográfica Computadorizada/métodos , Imageamento Tridimensional/métodos , Posicionamento do Paciente/métodos , Pneumorradiografia/métodos , Intensificação de Imagem Radiográfica/métodos , Adolescente , Adulto , Dióxido de Carbono/administração & dosagem , Colo/efeitos dos fármacos , Meios de Contraste/administração & dosagem , Dilatação/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Decúbito Ventral , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
20.
J Am Coll Radiol ; 21(4): 668-675, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37922969

RESUMO

PURPOSE: Multidisciplinary conferences (MDCs) are important for clinical care but are unreimbursed and can be time-consuming for radiologists to prepare for and present. The purpose of this single-center, prospective, survey-based study is to measure the per-conference time and total time radiologists devote to MDCs at a single academic medical center. Secondary objectives are to determine the source of radiologist preparation time, and calculate the per conference and overall radiology departmental costs of MDC participation. METHODS: A prospective survey was performed to capture all radiology preparation and presentation time for MDCs in a 3-month period, which was then annualized. Total cost was calculated on the basis of Association of Administrators in Academic Radiology survey data for nonchair academic radiologist compensation plus a 30% fringe-benefit rate. RESULTS: The survey response rate was 86.9%. A total of 3,358 hours were devoted annually to MDCs, which represents time equivalent to 1.9 full-time equivalents or $1,155,152 in unreimbursed radiology departmental costs. Per-MDC total preparation and presentation time was 2.7 hours, at an annual cost of $46,440 for each weekly MDC. Radiologists used a combination of personal time (49.7%), academic time (42%), and/or clinical time (35.4%) to prepare for MDCs. Radiologists devoted a mean of 47.9 hours (1.2 weeks) of time per annum to MDCs. CONCLUSIONS: Radiologist time devoted to MDCs at the survey institution was substantial, and preparation time was drawn disproportionately from personal and academic time, which may have negative implications for burnout, recruitment and retention, and academic productivity unless it is effectively mitigated.


Assuntos
Serviço Hospitalar de Radiologia , Radiologia , Humanos , Centros Médicos Acadêmicos , Radiologistas , Inquéritos e Questionários
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