Systematic review and meta-analysis of the diagnostic accuracy of ultrasonography for deep vein thrombosis

Background Ultrasound (US) has largely replaced contrast venography as the definitive diagnostic test for deep vein thrombosis (DVT). We aimed to derive a definitive estimate of the diagnostic accuracy of US for clinically suspected DVT and identify study-level factors that might predict accuracy. Methods We undertook a systematic review, meta-analysis and meta-regression of diagnostic cohort studies that compared US to contrast venography in patients with suspected DVT. We searched Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club, and citation lists (1966 to April 2004). Random effects meta-analysis was used to derive pooled estimates of sensitivity and specificity. Random effects meta-regression was used to identify study-level covariates that predicted diagnostic performance. Results We identified 100 cohorts comparing US to venography in patients with suspected DVT. Overall sensitivity for proximal DVT (95% confidence interval) was 94.2% (93.2 to 95.0), for distal DVT was 63.5% (59.8 to 67.0), and specificity was 93.8% (93.1 to 94.4). Duplex US had pooled sensitivity of 96.5% (95.1 to 97.6) for proximal DVT, 71.2% (64.6 to 77.2) for distal DVT and specificity of 94.0% (92.8 to 95.1). Triplex US had pooled sensitivity of 96.4% (94.4 to 97.1%) for proximal DVT, 75.2% (67.7 to 81.6) for distal DVT and specificity of 94.3% (92.5 to 95.8). Compression US alone had pooled sensitivity of 93.8 % (92.0 to 95.3%) for proximal DVT, 56.8% (49.0 to 66.4) for distal DVT and specificity of 97.8% (97.0 to 98.4). Sensitivity was higher in more recently published studies and in cohorts with higher prevalence of DVT and more proximal DVT, and was lower in cohorts that reported interpretation by a radiologist. Specificity was higher in cohorts that excluded patients with previous DVT. No studies were identified that compared repeat US to venography in all patients. Repeat US appears to have a positive yield of 1.3%, with 89% of these being confirmed by venography. Conclusion Combined colour-doppler US techniques have optimal sensitivity, while compression US has optimal specificity for DVT. However, all estimates are subject to substantial unexplained heterogeneity. The role of repeat scanning is very uncertain and based upon limited data

Extended Lower Limb Venous Ultrasound for the Diagnosis of Proximal and Distal Vein Thrombosis in Asymptomatic Patients after Total Hip Replacement

AbstractObjective. To assess the performance of extended lower limb venous ultrasound (US) for the diagnosis of asymptomatic deep vein thrombosis (DVT) and to estimate a 3-month DVT incidence on repeated US after total hip replacement.Design. Diagnostic performance study and prospective cohort study.Materials and methods. US was compared to phlebography in 70 consecutive patients and interobserver agreement was assessed in the last 48 patients at day 8. US was repeated in these 48 patients at day 13 and day 90.Results. Phlebography demonstrated a DVT in 18/70 (26%) patients, with five proximal and 13 distal and US in 23/70 (33%) patients, with eight proximal and 15 distal. Sensitivity and specificity of US with 95% CI were 94% (73–100) and 89% (76–96), respectively. Sensitivity in isolated distal vein thrombosis was 92% (67–99). The Kappa coefficient for agreement between observers was 0.84 (0.66–1.00). Follow-up showed a DVT in 15/48 (31%) patients on day 8, in 20/48 patients (42%) on day 13. DVT recurred in two patients during follow-up.Conclusions. The incidence of asymptomatic DVT is still significant despite prophylaxis but most DVTs remain distal and occur in the first 2 weeks. Extended US could replace phlebography for systematic screening in clinical trials using surrogate endpoints in view of its high accuracy and reliability

Multimodality Imaging of the Peripheral Venous System

The purpose of this article is to review the spectrum of image-based diagnostic tools used in the investigation of suspected deep vein thrombosis (DVT). Summary of the experience gained by the author as well as relevant publications, regarding vein imaging modalities taken from a computerized database, was reviewed. The imaging modalities reviewed include phlebography, color Doppler duplex ultrasonography (CDDUS), computerized tomography angiography (CTA) and venography (CTV), magnetic resonance venography (MRV), and radionuclide venography (RNV). CDDUS is recommended as the modality of choice for the diagnosis of DVT. A strategy combining clinical score and D-dimer test refines the selection of patients. Phlebography is reserved for discrepant noninvasive studies

Venous Thrombosis: Risk Factors and Management

During the past 2 decades, the diagnostic and therapeutic approach to deep vein thrombosis (DVT) has greatly evolved. First, the assessment of the clinical probability has gained wide acceptance. Second, novel noninvasive diagnostic tools such as venous compression ultrasonography and D-dimer measurement have become available, drastically reducing the need for invasive tools such as phlebography. Third, new anticoagulant drugs, in particular low-molecular-weight heparins (LMWHs), have become available and have made DVT treatment a lot easier by allowing out-ofhospital management. Several diagnostic algorithms, based on the assessment of clinical probability, D-dimer measurement and venous compression ultrasonography, have shown to be safe in management studies. In addition to improvements in diagnostic algorithms and anticoagulant treatment, compression therapy by elastic stockings to diminish the prevalence of the postthrombotic syndrome has been validated in prospective studies. The dilemma of the need or no need for looking for and treating isolated calf DVT with anticoagulants remains a controversial issue, as do the optimal length and intensity of anticoagulation. In the near future, the emergence of several new, totally synthetic, orally active anticoagulant compounds, such as direct thrombin or factor Xa inhibitors that are presently being tested in clinical studies, could profoundly change the therapeutic approach to DV

Point-of-Care Ultrasound in the Emergency Department

Point-of-care ultrasound (POCUS) is a useful diagnostic tool and has become an integral part of the care provided in the Emergency Department. It has evolved over the past two decades to include diagnostic and therapeutic skills. POCUS helps emergency physicians improve their diagnostic accuracy and provide better overall patient care. This chapter will summarize 13 core POCUS applications that are considered within the diagnostic armamentarium of all emergency physicians

Excluding venous thromboembolism using point of care D-dimer tests in outpatients: a diagnostic meta-analysis

Objective To review the evidence on the diagnostic accuracy of the currently available point of care D-dimer tests for excluding venous thromboembolism

Ultrasonography in Emergency Department; a Diagnostic Tool for Better Examination and Decision-Making

Context: The aim of this study is to evaluate the applications of ultrasonography (US) as a diagnostic tool in emergency settings. Evidence acquisition: In the present review article, search engines and scientific databases of Google Scholar, Science Direct, PubMed, Medline, Scopus, and Cochrane were searched for the applications of US in emergencies. Finally, related articles which were published between 2000 and 2017, were selected and by reviewing them an attempt was made to evaluate various applications of US for examining and facilitating decision-making in emergency department (ED). Results: As a diagnostic tool, US can be of diagnostic help in emergency settings for the specialists and the treatment team regarding trauma, measuring intracranial pressure (ICP), hemothorax pneumothorax, abscess and its drainage, deep vein thrombosis (DVT), dyspnea, acute abdomen, appendicitis and biliary problems, renal colic and renal stones, shock, foreign object, bone fracture, peripheral nerve block, establishing central and peripheral venous access, lumbar puncture (LP), and confirmation of nasogastric tube (NGT) and endotracheal tube (ETT) placement. Conclusion: The results of this review study showed that US can be of help to EMPs as a diagnostic tool in a wide range of diseases and clinical conditions, which in turn can result in a decrease in the time needed for diagnosis and treatment, and therefore improve both the quality and quantity of the service provided in ED

Validation of two age dependent D-dimer cut-off values for exclusion of deep vein thrombosis in suspected elderly patients in primary care: retrospective, cross sectional, diagnostic analysis

Objective To determine whether the use of age adapted D-dimer cut-off values can be translated to primary care patients who are suspected of deep vein thrombosis