Cost-effective imaging for resectability of liver lesions in colorectal cancer: an economic decision model.

BACKGROUND: This study aimed to determine the cost-effectiveness of contrast-enhanced magnetic resonance imaging (CE-MRI) compared with multiphase CE computed tomography (CE-CT) scan to characterize suspected liver lesions in patients with known colorectal carcinoma. METHODS: A decision analytic model linking diagnostic accuracy to health outcomes in patients with colorectal carcinoma was constructed. The model assumed that CE-MRI has superior sensitivity and equivalent specificity to CE-CT, and patients with a colorectal liver metastasis could be eligible for curative surgery or chemotherapy and palliation. Delayed diagnosis or misdiagnosis was associated with worse health outcomes (disutility). Cost-effectiveness was calculated as the incremental cost relative to the incremental benefit, the benefit was estimated using quality-adjusted life years. Sensitivity analyses were conducted to test the robustness of the results. RESULTS: The clinical evidence supports increased sensitivity of CE-MRI compared with CE-CT (0.943 versus 0.768). CE-MRI was more effective and more costly than CE-CT. The incremental cost-effectiveness ratio was estimated to be $40 548 per quality-adjusted life year gained. The model is most sensitive to the cost of MRI, cost of palliative treatment and the disutility associated with delayed palliative care. The results were also sensitive to the assumptions made about the clinical algorithm. CONCLUSION: The results provide evidence of the potential cost-effectiveness associated with CE-MRI for the diagnosis of liver metastases in patients with identified colorectal carcinoma. CE-MRI can be recommended as cost-effective provided it replaces CE-CT and that improved diagnostic accuracy results in earlier, curative, disease management.

Clinical safety and effectiveness of transversus abdominis plane (TAP) block in post-operative analgesia: a systematic review and meta-analysis.

Transversus abdominis plane (TAP) blocks can provide analgesia postoperatively for a range of surgeries. Abundant clinical trials have assessed TAP block showing positive analgesic effects. This systematic review assesses safety and effectiveness outcomes of TAP block in all clinical settings, comparing with both active (standard care) and inactive (placebo) comparators. PubMed, EMBASE, The Cochrane Library and the University of York CRD databases were searched. RCTs were screened for their eligibility and assessed for risk of bias. Meta-analyses were performed on available data. TAP block showed an equivalent safety profile to all comparators in the incidence of nausea (OR = 1.07) and vomiting (OR = 0.81). TAP block was more effective in reducing morphine consumption [MD = 13.05, 95% CI (8.33, 51.23)] and in delaying time to first analgesic request [MD = 123.49, 95% CI (48.59, 198.39)]. Postoperative pain within 24 h was reduced or at least equivalent in TAP block compared to its comparators. Therefore, TAP block is a safe and effective procedure compared to standard care, placebo and other analgesic techniques. Further research is warranted to investigate whether the TAP block technique can be improved by optimizing dose and technique-related factors.

Gadoxetic acid-enhanced MRI for the characterization of hepatocellular carcinoma: A systematic review and meta-analysis.

PURPOSE: To establish the relative diagnostic accuracy of gadoxetic acid-enhanced magnetic resonance imaging (GA-MRI) compared with contrast-enhanced computed tomography (CE-CT), dynamic MRI (D-MRI), gadopentetic acid-enhanced MRI (GP-MRI), or gadobenic acid-enhanced MRI (GB-MRI) in the characterization of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: PubMed, EMBASE, the Cochrane Library, and the University of York CRD databases were searched to February 29 2016 for any studies that compared the diagnostic accuracy of GA-MRI to CE-CT, D-MRI, GP-MRI, or GB-MRI in patients with known or suspected HCC. Diagnostic accuracy outcomes (true positive, true negative, false positive, false negative) were extracted and analyzed using the bivariate model of Reitsma et al (2005). RESULTS: In studies comparing GA-MRI to CE-CT in patients with any-sized lesions, estimated sensitivities were 0.881 (95% confidence interval [CI] = 0.766, 0.944) and 0.713 (95% CI = 0.577, 0.819) respectively. Estimated specificities were 0.926 (95% CI = 0.829, 0.97) and 0.918 (95% CI = 0.829, 0.963), respectively. This difference was not statistically significant. In studies including patients with small lesions GA-MRI was superior to CE-CT, with estimated sensitivities of 0.919 (95% CI = 0.834, 0.962) and 0.637 (95% CI = 0.565, 0.704 and estimated specificities of 0.936 (95% CI = 0.882, 0.966) and 0.971 (95% CI = 0.937, 0.987), respectively. In studies comparing GA-MRI to D-MRI in patients with any-sized lesions estimated sensitivities were 0.907 (95% CI = 0.870, 0.934) and 0.820 (95% CI = 0.776, 0.857); estimated specificities were 0.929 (95% CI = 0.877, 0.961) and 0.934 (95% CI = 0.881, 0.964). CONCLUSION: GA-MRI has superior diagnostic ability to CE-CT in patients with small lesions. In patients with any-sized lesions there is no evidence that GA-MRI is superior to either CE-CT to D-MRI. LEVEL OF EVIDENCE: 3 J. Magn. Reson. Imaging 2017;45:281-290.

Comparative diagnostic accuracy of hepatocyte-specific gadoxetic acid (Gd-EOB-DTPA) enhanced MR imaging and contrast enhanced CT for the detection of liver metastases: a systematic review and meta-analysis.

PURPOSE: This systematic review evaluated the diagnostic accuracy and impact on patient management of hepatocyte-specific gadoxetic acid enhanced magnetic resonance imaging (GA-MRI) compared to contrast enhanced computed tomography (CE-CT) in patients with liver metastases. METHOD: Four biomedical databases (PubMed, EMBASE, Cochrane Library, York CRD) were searched from January 1991 to February 2016. Studies investigating the accuracy or management impact of GA-MRI compared to CE-CT in patients with known or suspected liver metastases were included. Bias was evaluated using QUADAS-II. Univariate meta-analysis of sensitivity ratios (RR) were conducted in the absence of heterogeneity, calculated using I 2 , Tau values (τ) and prediction intervals. RESULTS: Nine diagnostic accuracy studies (537 patients with 1216 lesions) and four change in management studies (488 patients with 281 lesions) were included. Per-lesion sensitivity and specificity estimates for GA-MRI ranged from 86.9-100.0 % and 80.2-98.0 %, respectively, compared to 51.8-84.6 % and 77.2-98.0 % for CE-CT. Meta-analysis found GA-MRI to be significantly more sensitive than CE-CT (RR = 1.29, 95 % CI = 1.18-1.40, P < 0.001), with equivalent specificity (RR = 0.97, 95 % CI 0.910-1.042, P = 0.44). The largest difference was observed for lesions smaller than 10 mm for which GA-MRI was significantly more sensitive (RR = 2.21, 95 % CI = 1.47-3.32, P < 0.001) but less specific (RR = 0.92, 95 % CI 0.87-0.98, P = 0.008). GA-MRI affected clinical management in 26 of 155 patients (16.8 %) who had a prior CE-CT; however, no studies investigated the consequences of using GA-MRI instead of CE-CT. CONCLUSION: GA-MRI is significantly more sensitive than CE-CT for detecting liver metastases, which leads to a modest impact on patient management in the context of an equivocal CE-CT result.

Continuous paravertebral block for post-cardiothoracic surgery analgesia: a systematic review and meta-analysis.

A continuous paravertebral block is used when pain relief is required beyond the duration of a single-injection paravertebral block. Surgical procedures requiring an incision into the pleural cavity are some of the most painful procedures postoperatively and, if not managed appropriately, can lead to chronic pain. The current gold standard for post-cardiothoracic surgery pain management is epidural analgesia, which has contraindications, a failure rate of up to 12% and risk of complications such as epidural abscess and spinal haematoma. This systematic review and meta-analysis aimed to investigate the use of a continuous paravertebral block for post-cardiothoracic surgery analgesia. Randomized controlled trials evaluating the continuous paravertebral block against epidural analgesia, wound infiltration, placebo or standard care (intravenous opioids) for post-cardiothoracic surgery analgesia were considered for inclusion in the systematic review. PubMed, EMBASE, The Cochrane Library and the University of York Centre for Reviews and Dissemination databases were searched from inception to 15 September 2014. Risk of bias and generalizability were assessed using a modified Downs and Black checklist. A meta-analysis was conducted on suitable studies comparing the continuous paravertebral nerve block with epidural anaesthesia, with fixed-effects models being used to pool the effects. Twenty-three randomized controlled trials with 1120 participants were included. The continuous paravertebral block was associated with a significant improvement in incidence of nausea and vomiting (odds ratio = 0.29, 95% confidence interval = [0.16, 0.56]), hypotension (odds ratio = 0.16, 95% confidence interval = [0.06, 0.41]) and urinary retention (odds ratio = 0.22, 95% confidence interval = [0.09, 0.52]) compared with the epidural block. No statistically significant difference in pain relief was reported. The continuous paravertebral block has equivalent analgesic effects to epidural analgesia, wound infiltration and standard care, but is associated with a lower incidence of nausea and vomiting, hypotension and urinary retention than epidural analgesia.