Ben A. Dwamena

Meta-analysis: effectiveness of drugs for preventing contrast-induced nephropathy.

Context Contrast-induced nephropathy is a common cause of acute renal failure in hospitalized patients. Clinicians use a variety of contrast agents to reduce the risk for contrast-induced nephropathy, including N-acetylcysteine, theophylline, fenoldopam, dopamine, furosemide, mannitol, and bicarbonate. Contribution Although all of the agents included in this analysis reduced the risk for contrast-induced nephropathy, this meta-analysis of 33 trials involving 3622 patients found the strongest evidence for the effectiveness of N-acetylcysteine, mannitol, and theophylline when compared with periprocedural hydration alone. Caution Available studies examined laboratory end points (such as an increase in serum creatinine levels) rather than clinical end points (such as dialysis or death). The Editors Contrast-induced nephropathy, defined as an increase in serum creatinine greater than 25% or 44.2 mol/L (>0.5 mg/dL) within 3 days of intravascular contrast administration in the absence of an alternative cause, is the third most common cause of new acute renal failure in hospitalized patients (1, 2). Contrast-induced nephropathy develops in 0% to 10% of patients with normal renal function (3). However, the incidence may be as high as 25% in patients with preexisting renal impairment or certain risk factors, such as diabetes, congestive heart failure, advanced age, and concurrent administration of nephrotoxic drugs (3). Large doses of intravenous contrast and use of high-osmolar contrast agents in patients with renal impairment also increase the risk for contrast-induced nephropathy (46). High-osmolar contrast agents are more rarely used now. The risk difference between iso-osmolar agents, such as iodixanol, and low-osmolar agents, such as iopamidol, ioxaglate, or iohexol, is less clear (79). Most episodes of contrast-induced nephropathy are not detected clinically because patients are asymptomatic. However, contrast-induced nephropathy may increase the risk for renal failure and is associated with dialysis, prolonged hospital stay, increased health care costs, potentially irreversible reduction in renal function, and death (10). Use of preprocedural fluids and low-osmolar or iso-osmolar contrast agents has been shown to decrease the risk for contrast-induced nephropathy (1113). These measures suffice for many patients; however, the risk is reduced but not eliminated in some patientseven when iso-osmolar contrast is used (14, 15). Other studies have evaluated the use of N-acetylcysteine, theophylline, fenoldopam, and other agents as preventive strategies in contrast-induced nephropathy; the results have been heterogeneous and are difficult to compare across the different treatment strategies. Given the widespread use of iodinated intravascular contrast agents, an improved understanding of the potential value of these agents has important patient safety and cost implications. We conducted a meta-analysis of the literature to quantify the effects of individual strategies on the prevention of contrast-induced nephropathy and to facilitate comparison of preventive effects across strategies. Methods Study Search Strategy We performed a computerized search by using standard meta-analytic techniques (16) to identify relevant articles in MEDLINE (from 1966 through 3 November 2006), EMBASE (1980 through November 2006), PubMed, Web of Knowledge (Current Contents Connect, Web of Science, BIOSIS Previews, and ISI Proceedings for the latest 5 years), and the Cochrane Library databases. For the MEDLINE search, we used the following combination of keywords: [renal failure or kidney failure to include all subheadings] and [contrast media or iopamidol or iodine or ioxaglic acid or iodine compounds or iohexol or urography or drug hyper sensitivity or tomography, X ray computed or diatrizoate] and [hydration or fluid therapy or water or dehydration or skin or nutritional support or body water] and [clinical trial or randomized, controlled trial] and [prospective trial or prospective studies or clinical trials] and [adult or middle aged or aged] and [N-Acetylcysteine or acetylcysteine] or [theophylline] or [mannitol] or [dopamine] or [fenoldopam] or [bicarbonate]. For the PubMed, Cochrane Library Database, and Web of Knowledge searches, we used the search words renal failure, contrast medium, hydration, randomized, controlled trial, N acetyl cysteine, Theophylline, Mannitol, Fenoldopam, Dopamine and Bicarbonate. We included English-, French-, German-, Spanish- and Italian-language studies and clinical trials and excluded review articles and nonhuman studies. We combined this strategy with a manual search of reference lists from identified articles. Study Selection We included a study if 1 of the treatment groups received N-acetylcysteine, theophylline, fenoldopam, iloprost, statin, dopamine, trimetazidine, bicarbonate, ascorbic acid, furosemide, or mannitol. Criteria for inclusion were randomized, controlled trials that compared treatment with control; used intravenous iodinated contrast; explicitly defined contrast-induced nephropathy; and sufficiently reported data to construct a 22 table and calculate the primary effect measure (relative risk reduction). Where data were missing, we contacted the original authors for the relevant information. Data Extraction One reviewer examined the abstracts to determine whether the study met the inclusion and exclusion criteria. Two reviewers separately abstracted complete articles according to a standardized form for studies meeting criteria. Abstracted information included patient characteristics (mean age, proportion of men and patients with diabetes mellitus or hypertension, and mean baseline creatinine level), type of radiologic or cardiologic imaging, inclusion and exclusion criteria, type of contrast media and dose used, periprocedural hydration, specific definition of contrast-induced nephropathy, prophylactic agent dose and route, and serum creatinine level at baseline and at 48 hours after contrast injection. Analysis of Renoprotective Agents The primary outcome was the development of contrast-induced nephropathy, defined as an absolute increase in baseline serum creatinine greater than 44.2 mol/L (>0.5 mg/dL) or a relative increase greater than 25% at 48 hours after contrast injection. For trials missing this datum, we contacted the original authors to get the number of patients with this outcome. We calculated individual study relative risks and 95% CIs before aggregation. Subsequently, we obtained overall and subgroup summary risk ratios by random-effects modeling of the binary data from the multiple 22 tables. We used the method of DerSimonian and Laird (17), with the estimate of heterogeneity taken from the inverse variance fixed-effect model. We used the metan module in Stata, version 9.0 (Stata, College Station, Texas), to perform data synthesis. We performed subgroup evaluation of each therapeutic regimen. In studies comparing 2 dosage regimens of the same intervention with a single control group (1820), we considered the same-study dosage groups as representing a single intervention to avoid double-counting of shared control observations. When we identified only 1 study that examined a given therapy, we assigned that study to a group termed other and pooled data from all such studies together. This group included 1 study each on the use of iloprost; trimetazidine; mannitol; bicarbonate; ascorbic acid; and combinations of furosemide, dopamine, and mannitol and furosemide and dopamine. We used relative risk ratios to estimate the treatment effects. Assessment of Methodological Quality Criteria for quality assessment included concealment of allocation, similarity of both groups at baseline regarding prognostic indicators, eligibility criteria, blinding of patient, blinding of care provider, blinding of outcome assessor, point estimates and measures of variability for the primary outcome measure, and inclusion of an intention-to-treat analysis (21). Any disagreements in abstracted data between the reviewers were adjudicated by a third reviewer. We explored potential heterogeneity in estimates of treatment efficacy attributable to each quality criterion by using meta-regression. Assessment of Heterogeneity We used Forest plots to visualize the extent of heterogeneity among studies. We also examined I 2, a standard test for heterogeneity that measures the degree of inconsistency across studies. I 2 values, which range from 0% to 100%, describe the proportion of variation in treatment effect estimates that is due to genuine variation rather than sampling error (22). A value of 0% indicates no observed heterogeneity. Higgins and colleagues (22) suggest describing I 2 values of 25%, 50%, and 75% as low, moderate, and high, respectively. We obtained the group-specific and overall I 2 as standard output of the metan program. We performed an Egger precision-weighted linear regression test as a statistical test of funnel plot asymmetry and publication bias (23). All statistical analyses were performed with Stata. Results Study Identification Our initial search yielded 619 citations and references. We excluded 531 studies on the basis of our criteria, including nonclinical trials; trials not conducted on humans; trials not reported in English, French, German, Spanish, or Italian; trials reporting only nonnephropathy outcomes; and trials using nonclinical outcome measures, leaving 88 studies that met the inclusion criteria (Figure 1). We reviewed abstracts from the 88 articles and excluded an additional 23 trials, including nonrandomized clinical trials; trials not conducted on humans; trials not reported in English, French, German, Spanish, or Italian; trials reporting only nonnephropathy outcomes; and trials that used nonclinical outcome measures, leaving 65 studies for full publication review. The full articles were then reviewed, and a further 24 studies were excluded for reasons similar to t

Solitary Pulmonary Nodules: Meta-analytic Comparison of Cross-sectional Imaging Modalities for Diagnosis of Malignancy

PURPOSE To perform a meta-analysis to estimate the diagnostic accuracy of dynamic contrast material-enhanced computed tomography (CT) and magnetic resonance (MR) imaging, fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET), and technetium 99m ((99m)Tc) depreotide single photon emission computed tomography (SPECT) for evaluation of solitary pulmonary nodules (SPNs). MATERIALS AND METHODS Data sources were studies published in PubMed between January 1990 and December 2005. The selected investigations were comparative and noncomparative diagnostic cohort studies to examine the operating characteristics of the four imaging modalities for evaluation of SPNs, involving at least 10 enrolled participants with histologic confirmation and having sufficient data to calculate contingency tables. A random coefficient binary regression model with disease probability conditioned on test results was used to summarize test performance and construct summary receiver operating characteristic (ROC) curves. Sensitivities, specificities, predictive values, diagnostic odds ratios, and areas under the ROC curve were calculated. RESULTS Forty-four studies--10 dynamic CT, six dynamic MR, 22 FDG PET, and seven (99m)Tc-depreotide SPECT--met the inclusion criteria. (One study was included in both the FDG PET and SPECT groups.) Sensitivities, specificities, positive predictive values, negative predictive values, diagnostic odds ratios, and areas under the ROC curve were, respectively, 0.93 (95% confidence interval [CI]: 0.88, 0.97), 0.76 (95% CI: 0.68, 0.97), 0.80 (95% CI: 0.74, 0.86), 0.95 (95% CI: 0.93, 0.98), 39.91 (95% CI: 1.21, 81.04), and 0.93 (95% CI: 0.81, 0.97) for dynamic CT; 0.94 (95% CI: 0.91, 0.97), 0.79 (95% CI: 0.73, 0.86), 0.86 (95% CI: 0.83, 0.89), 0.93 (95% CI: 0.90, 0.96), 60.59 (95% CI: 5.56, 115.62), and 0.94 (95% CI: 0.83, 0.98) for dynamic MR; 0.95 (95% CI: 0.93, 0.98), 0.82 (95% CI: 0.77, 0.88), 0.91 (95% CI: 0.88, 0.93), 0.90 (95% CI: 0.85, 0.94), 97.31 (95% CI: 6.26, 188.37), and 0.94 (95% CI: 0.83, 0.98) for FDG PET; and 0.95 (95% CI: 0.93, 0.97), 0.82 (95% CI: 0.78, 0.85), 0.90 (95% CI: 0.83, 0.97), 0.91 (95% CI: 0.84, 0.98), 84.50 (95% CI: 34.28, 134.73), and 0.94 (95% CI: 0.83, 0.98) for (99m)Tc-depreotide SPECT. CONCLUSION Dynamic CT and MR, FDG PET, and (99m)Tc-depreotide SPECT are noninvasive and accurate in distinguishing malignant from benign SPNs; differences among these tests are nonsignificant.

Primary Sclerosing Cholangitis: Meta-Analysis of Diagnostic Performance of MR Cholangiopancreatography

PURPOSE To determine the diagnostic accuracy of magnetic resonance cholangiopancreatography (MRCP) for detection of primary sclerosing cholangitis (PSC) in patients with biochemical cholestasis. MATERIALS AND METHODS Two reviewers searched MEDLINE, EMBASE, and other electronic databases to identify prospective studies in which MRCP was evaluated and compared with endoscopic retrograde cholangiopancreatography (ERCP), clinical examination, and/or histologic analysis for diagnosis of PSC in cholestasis and control cases. Main study inclusion criteria were (a) use of ERCP or percutaneous transhepatic cholangiography (PTC) as part of the reference standard for the diagnosis of PSC, (b) inclusion of patients with hepatobiliary disease other than PSC (ie, nonhealthy control subjects), (c) blinding of MRCP image readers to reference-standard results, (d) prospective study with ERCP or MRCP performed after subject recruitment into the study, and (e) inclusion of raw data (for true-positive, false-positive, true-negative, and false-negative results) that could be found or calculated from the original study data. Major exclusion criteria were duplicate article (on a primary study) that contained all or some of the original study data and inclusion of fewer than 10 patients with PSC. Methodologic quality was assessed by using the Quality Assessment of Diagnostic Accuracy Studies tool. Bivariate random-effects meta-analytic methods were used to estimate summary, sensitivity, specificity, and receiver operating characteristic (ROC) curves. RESULTS Six manuscripts with 456 subjects (with 623 independent readings)--185 with PSC--met the study inclusion criteria. The summary area under the ROC curve was 0.91. High heterogeneity (inconsistency index, 78%) was found but became moderate (inconsistency index, 36%) with the exclusion of one study in which the diagnostic threshold was set for high sensitivity. There was no evidence of publication bias (P = .27, bias coefficient analysis). Sensitivity and specificity of MRCP for PSC detection across all studies were 0.86 and 0.94, respectively. Positive and negative likelihood ratios with MRCP were 15.3 and 0.15, respectively. In patients with high pretest probabilities, MRCP enabled confirmation of PSC; in patients with low pretest probabilities, MRCP enabled exclusion of PSC. Worst-case-scenario (pretest probability, 50%) posttest probabilities were 94% and 13% for positive and negative MRCP results, respectively. CONCLUSION MRCP has high sensitivity and very high specificity for diagnosis of PSC. In many cases of suspected PSC, MRCP is sufficient for diagnosis, and, thus, the risks associated with ERCP can be avoided.

Breast Cancer : Sentinel Node Identification and Classification after Neoadjuvant Chemotherapy—Systematic Review and Meta Analysis

RATIONALE AND OBJECTIVES Breast cancer is the leading cause of mortality in women worldwide. Lymphatic mapping with sentinel node biopsy has the potential to reduce the morbidity associated with breast cancer staging in women after neoadjuvant therapy. MATERIALS AND METHODS A systematic search of world literature between 1996 and 2007 of sentinel node mapping in patients with early-stage breast carcinoma after chemotherapy was undertaken. Potentially eligible studies were identified using database-specific search strategies incorporating appropriate Boolean combinations of the keywords sentinel node biopsy or sentinel node localization or lymphatic mapping; breast cancer or malignancy or neoplasm; and preoperative or neoadjuvant chemotherapy. The electronic searches were augmented with a manual search of reference lists from identified articles. Successful lymph node mapping, defined as successful identification rate (SIR), and false-negative rate (FNR) was summarized using a bivariate random effects mixed model. The extent of heterogeneity was assessed using the inconsistency statistic. The effect of study level covariates, such as use of immunohistochemistry or dual mapping technique, and individual quality criteria, such as study design or multi-institution participation, on SIR and FNR were analyzed using metaregression. RESULTS A total of 24 trials of 1799 subjects were reported that met eligibility criteria. All studies identified were published between 2000 and 2007. Lymph node involvement was found in 758 patients (37%) and ranged from 25% to 96% across studies. The proportion of patients who had successful lymph node mapping ranged from 63% to 100%, with 79% of studies reporting a rate of less than 95%. The summary successful identification rate was 0.896 (95% confidence interval [CI] 0.860-0.923) with moderate heterogeneity. The summary FNR was 0.084 (95% CI 0.064-0.109) with no significant heterogeneity. Increasing prevalence of lymph node involvement and same-day mapping and lymph node dissection both significantly reduced the FNR. CONCLUSIONS The present systematic review demonstrates robust estimates of successful identification rate and false-negative rates of sentinel lymph node mapping and biopsy after neoadjuvant therapy for early-stage breast cancer patients. With a 90% SIR and 8% FNR, this technique is a reliable tool for planning treatment in this population as an alternative to completion axillary lymph node dissection.

The prognostic power of the nod2 genotype for complicated crohn's disease: A meta-analysis

OBJECTIVES:Crohns disease is often purely inflammatory at presentation, but most patients develop strictures and fistulae over time (complicated disease). Many studies have suggested that nucleotide-binding oligomerization domain 2 (NOD2) mutations are associated with a varying but increased risk of complicated disease. An accurate and sufficiently powerful predictor of complicated disease could justify the early use of biological therapy in high-risk individuals. We performed a systematic review and meta-analysis to obtain accurate estimates of the predictive power of the identified mutations (such as p.R702W, P.G908R, and p.Leu1007fsX1008) in NOD2 for the risk of complicated disease.METHODS:An electronic search of MEDLINE, Embase, and Web of Science identified 917 relevant papers. Inclusion required specification of genetic mutations at the individual level and disease phenotypes by Vienna classification (inflammatory (B1), stricturing (B2), and fistulizing (B3)). A total of 49 studies met these criteria, which included 8,893 subjects, 2,897 of whom had NOD2 mutations. Studies were weighted by median disease duration. Studies not providing duration data were weighted at the level of the study with the shortest disease duration (3.9 years).RESULTS:The relative risk (RR) of the presence of any NOD2 mutant allele for complicated disease (B2 or B3) was 1.17 (95% confidence interval (95% CI) 1.10–1.24; P<0.001). P.G908R was associated with an RR of complicated disease of 1.33 (95% CI 1.11–1.60; P=0.002). NOD2 did not predict perianal disease (P=0.4). The RR of surgery was 1.58 (95% CI 1.38–1.80; P<0.001). There was substantial heterogeneity across all studies (I2=66.7%). On the basis of logistic regression of these data, the sensitivity of any mutation in predicting complicated disease was 36% and specificity was 73%, with the area under the receiver operating characteristic curve 0.56.CONCLUSIONS:The presence of a single NOD2 mutation predicted an 8% increase in the risk for complicated disease (B2 or B3), and a 41% increase with 2 mutations. Surgery risk is increased by 58% with any NOD2 mutation, whereas perianal disease was unchanged. The predictive power associated with a single NOD2 mutation is weak. The RR of any NOD2 mutations for complicated disease was only 17% across 36 studies. However, the presence of two NOD2 mutations had 98% specificity for complicated disease. These data provide insufficient evidence to support top-down therapy based solely on single NOD2 mutations, but suggest that targeted early-intensive therapy for high-risk patients with two NOD2 mutations might be beneficial, if prospective trials can demonstrate changes in the natural history in this subset of patients.

Ultrasonographic differentiation of malignant from benign breast lesions: a meta-analytic comparison of elasticity and BIRADS scoring

There has been controversy regarding the accuracy of breast ultrasound elastography (USE) compared to conventional B-mode Ultrasound (USB). The purpose of this study was to conduct a direct comparative effectiveness analysis of USB versus USE or their combination in differentiating breast lesions through systematically reviewing recent literature. An extensive literature search of PubMed and other medical and general purpose databases from inception through August 2011 was conducted. Published studies that reported a direct comparison of the diagnostic performance of USE, using elasticity score versus USB, using breast imaging reporting and data system (BIRADS) for characterization of focal breast lesions were included. Summary diagnostic performance measures were assessed for each of the tests and their combination using bivariate generalized linear mixed modeling. The two tests were combined as: (1) conjunctive, where the outcome of the combination of tests is positive only if both test results are positive; (2) disjunctive, where the outcome of a combination of tests is negative only if both tests are negative. Twenty nine studies provided relevant information on 5,511 breast masses (2,065 cancers, 3,446 benign lesions). Sensitivity of USB, USE, and their conjunctive and disjunctive combinations were 96% (95% credible interval (CrI), 93–98%), 79% (95% CrI, 74–83%), 73% (95% CrI, 67–78%), and 99% (95% CrI, 98–99%), respectively. Specificity of USB, USE, and their conjunctive and disjunctive combinations were 70% (95% CrI, 55–83%), 88% (95% CrI, 82–92%), 97% (95% CrI, 95–99%), and 56% (95% CrI, 43–69%), respectively. The application of USE as a single test is not superior to USB alone. However, in low risk patients it is recommended to perform an USE following a positive USB result to decrease the rate of unnecessary biopsies.

Amyloid deposition in Parkinson's disease and cognitive impairment: A systematic review

Varying degrees of cortical amyloid deposition are reported in the setting of Parkinsonism with cognitive impairment. We performed a systematic review to estimate the prevalence of Alzheimer disease (AD) range cortical amyloid deposition among patients with Parkinsons disease with dementia (PDD), Parkinsons disease with mild cognitive impairment (PD‐MCI) and dementia with Lewy bodies (DLB). We included amyloid positron emission tomography (PET) imaging studies using Pittsburgh Compound B (PiB).

Dual-source computed tomography angiography for diagnosis and assessment of coronary artery disease: Systematic review and meta-analysis

BACKGROUND Development of an accurate test for noninvasive assessment of coronary arteries has been highly desirable. OBJECTIVES We performed a systematic review of diagnostic accuracy of the dual-source computed tomography (DSCT) in the diagnosis of coronary artery disease (CAD). METHODS Eight medical databases were searched for articles published from January 2005 through March 2011. Studies compared DSCT coronary angiography (DSCT-CA) and invasive coronary angiography, as the reference standard, in consecutive patients with suspected or known CAD, and relevant data were extracted by 2 independent reviewers. Summary diagnostic accuracies were calculated, and the effect of covariates on the diagnostic performance was evaluated by meta-regression. RESULTS Twenty-five studies were included. In per-patient analysis (n = 2303), pooled sensitivity was 99% [95% confidence interval (CI), 97%-99%] with specificity of 89% (95% CI, 84%-92%). The summary positive (+LR) and negative (-LR) likelihood ratios were 8.6 (95% CI, 6.4-11.6) and 0.02 (95% CI, 0.01-0.03), respectively. In per-segment analysis (n = 32,615), pooled sensitivity was 94% (95% CI, 92%-96%) with specificity of 97% (95% CI, 96%--98%). Summary +LR and -LR were 30.2 (95% CI, 22.1-43.5) and 0.06 (95% CI, 0.04-0.08), respectively. CONCLUSIONS DSCT-CA seems to be robust to elevate heart rates while maintaining a high level of diagnostic performance.

Diagnostic accuracy of diffusion tensor imaging in amyotrophic lateral sclerosis: A systematic review and individual patient data meta-analysis

RATIONALE AND OBJECTIVES There have been a large number of case-control studies using diffusion tensor imaging (DTI) in amyotrophic lateral sclerosis (ALS). The objective of this study was to perform an individual patient data (IPD) meta-analysis for the estimation of the diagnostic accuracy measures of DTI in the diagnosis of ALS using corticospinal tract data. MATERIALS AND METHODS MEDLINE, EMBASE, CINAHL, and Cochrane databases (1966-April 2011) were searched. Studies were included if they used DTI region of interest or tractography techniques to compare mean cerebral corticospinal tract fractional anisotropy values between ALS subjects and healthy controls. Corresponding authors from the identified articles were contacted to collect individual patient data. IPD meta-analysis and meta-regression were performed using Stata. Meta-regression covariate analysis included age, gender, disease duration, and Revised Amyotrophic Lateral Sclerosis Functional Rating Scale scores. RESULTS Of 30 identified studies, 11 corresponding authors provided IPD and 221 ALS patients and 187 healthy control subjects were available for study. Pooled area under the receiver operating characteristic curve (AUC) was 0.75 (95% CI: 0.66-0.83), pooled sensitivity was 0.68 (95% CI: 0.62-0.75), and pooled specificity was 0.73 (95% CI: 0.66-0.80). Meta-regression showed no significant differences in pooled AUC for each of the covariates. There was moderate to high heterogeneity of pooled AUC estimates. Study quality was generally high. Data from 19 of the 30 eligible studies were not ascertained, raising possibility of selection bias. CONCLUSION Using corticospinal tract individual patient data, the diagnostic accuracy of DTI appears to lack sufficient discrimination in isolation. Additional research efforts and a multimodal approach that also includes ALS mimics will be required to make neuroimaging a critical component in the workup of ALS.

Comparative effectiveness of elastographic and B-mode ultrasound criteria for diagnostic discrimination of thyroid nodules: a meta-analysis.

OBJECTIVE The purpose of this article is to present, through systematic review of recent literature, a comparative effectiveness analysis of ultrasound elastography versus B-mode ultrasound features for differentiating thyroid nodules. MATERIALS AND METHODS We conducted an extensive literature search of PubMed and other medical and general purpose databases from January 1966 through March 2012. Eligible studies were published in English, reported diagnostic performance of elastography (using elasticity score or strain ratio) with or without B-mode ultrasound in differentiation of thyroid nodules, and used histology or cytology as the reference standard. Summary diagnostic performance measures were assessed for each of the elasticity measuring methods and ultrasound features by means of a bivariate random effects model. RESULTS Twenty-four studies provided relevant information on more than 2624 patients and 3531 thyroid nodules (927 malignant and 2604 benign). Six ultrasound features (echogenicity, calcifications, margins, halo sign, shape, and color Doppler flow pattern) were compared with elasticity score and strain ratio. The respective sensitivities and specificities were as follows: elasticity score, 82% and 82%; strain ratio, 89% and 82%; hypoechogenicity, 78% and 55%; microcalcifications, 50% and 80%; irregular margins, 66% and 81%; absent halo sign, 56% and 57%; nodule vertical development, 46% and 77%; and intranodular vascularization, 40% and 61%. CONCLUSION Evaluation of thyroid nodules with ultrasound elastography appears to be both more sensitive and specific than each of the ultrasound features. The former is a safe and effective technique that warrants further rigorous investigation or use in the clinical diagnosis of thyroid nodules.