Comparison of inversion recovery and contrast-enhanced T1-weighted fat-suppressed sequences for the staging of cervical lymphoma

In a retrospective analysis with two readers blinded to the clinical information, coronal short tau inversion recovery (STIR) images were compared to contrast-enhanced fat-saturated T1-weighted imaging (T1 CEfs) in 51 cases of cervical lymphoma. Interrater reliability was good to excellent. Although sensitivity and subjective quality of the STIR sequence were higher than those of the T1 CEfs sequence (sensitivity 85%/72%, respectively), specificity (82%/95%) as well as positive likelihood ratio (4.65/15.93) was much lower. Therefore, contrast-enhanced sequences should be included in the primary staging of lymphoma.

Pharmacological prevention of serious anaphylactic reactions due to iodinated contrast media: systematic review

OBJECTIVE: To review the efficacy of pharmacological prevention of serious reactions to iodinated contrast media. DESIGN: Systematic review. DATA SOURCES: Systematic search (multiple databases, bibliographies, all languages, to October 2005) for randomised comparisons of pretreatment with placebo or no treatment (control) in patients receiving iodinated contrast media. Review methods Trial quality was assessed by all investigators. Information on trial design, population, interventions, and outcomes was abstracted by one investigator and cross checked by the others. Data were combined by using Peto odds ratios with 95% confidence intervals. RESULTS: Nine trials (1975-96, 10 011 adults) tested H1 antihistamines, corticosteroids, and an H1-H2 combination. No trial included exclusively patients with a history of allergic reactions. Many outcomes were not allergy related, and only a few were potentially life threatening. No reports on death, cardiopulmonary resuscitation, irreversible neurological deficit, or prolonged hospital stays were found. In two trials, 3/778 (0.4%) patients who received oral methylprednisolone 2x32 mg or intravenous prednisolone 250 mg had laryngeal oedema compared with 11/769 (1.4%) controls (odds ratio 0.31, 95% confidence interval 0.11 to 0.88). In two trials, 7/3093 (0.2%) patients who received oral methylprednisolone 2x32 mg had a composite outcome (including shock, bronchospasm, and laryngospasm) compared with 20/2178 (0.9%) controls (odds ratio 0.28, 0.13 to 0.60). In one trial, 1/196 (0.5%) patients who received intravenous clemastine 0.03 mg/kg and cimetidine 2-5 mg/kg had angio-oedema compared with 8/194 (4.1%) controls (odds ratio 0.20, 0.05 to 0.76). CONCLUSIONS: Life threatening anaphylactic reactions due to iodinated contrast media are rare. In unselected patients, the usefulness of premedication is doubtful, as a large number of patients need to receive premedication to prevent one potentially serious reaction. Data supporting the use of premedication in patients with a history of allergic reactions are lacking. Physicians who are dealing with these patients should not rely on the efficacy of premedication.

Quantitative stress echocardiography in coronary artery disease using contrast-based myocardial blood flow measurements: prospective comparison with coronary angiography

AIM: To test whether quantitative stress echocardiography using contrast-based myocardial blood flow (MBF, ml x min(-1) x g(-1)) measurements can detect coronary artery disease in humans. METHODS: 48 patients eligible for pharmacological stress testing by myocardial contrast echocardiography (MCE) and willing to undergo subsequent coronary angiography were prospectively enrolled in the study. Baseline and adenosine-induced (140 microg x kg(-1) x min(-1)) hyperaemic MBF was analysed according to a three-coronary-artery-territory model. Vascular territories were categorised into three groups with increasing stenosis severity defined as percentage diameter reduction by quantitative coronary angiography. RESULTS: Myocardial blood flow reserve (MBFR)-that is, the ratio of hyperaemic to baseline MBF, was obtained in 128 (89%) territories. Mean (SD) baseline MBF was 1.073 (0.395) ml x min(-1) x g(-1) and did not differ between territories supplied by coronary arteries with mild (<50% stenosis), moderate (50%-74% stenosis) or severe (>or=75% stenosis) disease. Mean (SD) hyperaemic MBF and MBFR were 2.509 (1.078) ml x min(-1) x g(-1) and 2.54 (1.03), respectively, and decreased linearly (r2 = 0.21 and r2 = 0.39) with stenosis severity. ROC analysis revealed that a territorial MBFR <1.94 detected >or=50% stenosis with 89% sensitivity and 92% specificity. CONCLUSION: Quantitative stress testing based on MBF measurements derived from contrast echocardiography is a new method for the non-invasive and reliable assessment of coronary artery disease in humans.

Magnetization transfer contrast and T2 mapping in the evaluation of cartilage repair tissue with 3T MRI

PURPOSE: To use magnetization transfer (MT) imaging in the visualization of healthy articular cartilage and cartilage repair tissue after different cartilage repair procedures, and to assess global as well as zonal values and compare the results to T2-relaxation. MATERIALS AND METHODS: Thirty-four patients (17 after microfracture [MFX] and 17 after matrix-associated autologous cartilage transplantation [MACT]) were examined with 3T MRI. The MT ratio (MTR) was calculated from measurements with and without MT contrast. T2-values were evaluated using a multiecho, spin-echo approach. Global (full thickness of cartilage) and zonal (deep and superficial aspect) region-of-interest assessment of cartilage repair tissue and normal-appearing cartilage was performed. RESULTS: In patients after MFX and MACT, the global MTR of cartilage repair tissue was significantly lower compared to healthy cartilage. In contrast, using T2, cartilage repair tissue showed significantly lower T2 values only after MFX, whereas after MACT, global T2 values were comparable to healthy cartilage. For zonal evaluation, MTR and T2 showed a significant stratification within healthy cartilage, and T2 additionally within cartilage repair tissue after MACT. CONCLUSION: MT imaging is capable and sensitive in the detection of differences between healthy cartilage and areas of cartilage repair and might be an additional tool in biochemical cartilage imaging. For both MTR and T2 mapping, zonal assessment is desirable.

Myocardial contrast echocardiography for the distinction of hypertrophic cardiomyopathy from athlete's heart and hypertensive heart disease

BACKGROUND: Myocardial contrast echocardiography (MCE) is able to measure in vivo relative blood volume (rBV, i.e., capillary density), and its exchange frequency b, the constituents of myo-cardial blood flow (MBF, ml min-1 g-1). This study aimed to assess, by MCE, whether left ventricular hypertrophy (LVH) in hypertrophic cardiomyopathy (HCM) can be differentiated from LVH in triathletes (athlete's heart, AH) or from hypertensive heart disease patients (HHD). METHODS: Sixty individuals, matched for age (33 +/- 10 years) and gender, and subdivided into four groups (n = 15) were examined: HCM, AH, HHD and a group of sedentary individuals without LVH (S). rBV (ml ml-1), b (min-1) and MBF, at rest and during adenosine-induced hyperaemia, were derived by MCE in mid septal, lateral and inferior regions. The ratio of MBF during hyperaemia and MBF at rest yielded myocardial blood flow reserve (MBFR). RESULTS: Septal wall rBV at rest was lower in HCM (0.084 +/- 0.023 ml ml-1) than in AH (0.151 +/- 0.024 ml ml-1, p <0.01) and in S (0.129 +/- 0.026 ml ml-1, p <0.01), but was similar to HHD (0.097 +/- 0.016 ml ml-1). Conversely, MBFR was lowest in HCM (1.67 +/- 0.93), followed by HHD (2.8 +/- 0.93, p <0.01), by S (3.36 +/- 1.03, p <0.001) and by AH (4.74 +/- 1.46, p <0.0001). At rest, rBV <0.11 ml ml-1 accurately distinguished between HCM and AH (sensitivity 99%, specificity 99%), similarly MBFR < or =1.8 helped to distinguish between HCM and HHD (sensitivity 100%, specificity 77%). CONCLUSIONS: rBV at rest, most accurately distinguishes between pathological LVH due to HCM and physiological, endurance-exercise induced LVH.

Cardiovascular magnetization transfer ratio imaging compared with histology: A postmortem study

Cardiovascular magnetization transfer ratio (MTR) imaging by steady state free precession is a promising imaging method to assess microstructural changes within the myocardium. Hence, MTR imaging was correlated to histological analysis. Three postmortem cases were selected based on a suspicion of myocardial infarction. MTR and T2 -weighted (T2w ) imaging was performed, followed by autopsy and histological analysis. All tissue abnormalities, identified by autopsy or histology, were retrospectively selected on visually matched MTR and T2w images, and corresponding MTR values compared with normal appearing tissue. Regions of elevated MTR (up to approximately 20%, as compared to normal tissue), appearing hypo-intense in T2w -images, revealed the presence of fibrous tissue in microscopic histological analysis. Macroscopic observation (autopsy) described scar tissue only in one case. Regions of reduced MTR (up to approximately 20%) corresponded either to (i) the presence of edema, appearing hyperintense in T2w -images and confirmed by autopsy, or to (ii) inflammatory granulocyte infiltration at a microscopic level, appearing as hypo-intense T2w -signal, but not observed by autopsy. Findings from cardiovascular MTR imaging corresponded to histology results. In contrast to T2w -imaging, MTR imaging discriminated between normal myocardium, scar tissue and regions of acute myocardial infarction in all three cases. J. Magn. Reson. Imaging 2013. © 2013 Wiley Periodicals, Inc.

Leptomeningeal contrast enhancement and blood-CSF barrier dysfunction in aseptic meningitis

OBJECTIVE To investigate the blood-CSF barrier (BCSFB) dysfunction in aseptic meningitis. METHODS In our case series of 14 patients with acute aseptic meningitis, we compared MRI characteristics with CSF findings. RESULTS Contrast enhancement in the sulcal space in a leptomeningeal pattern was visualized in 7 patients with BCSFB dysfunction categorized as moderate to severe as evidenced by the CSF/serum albumin ratio (Qalb) but was not present in those with mild or no barrier disturbance (p = 0.001). The Qalb as a marker for the leakiness of the BCSFB and, more indirectly, of the blood-brain barrier (BBB) was positively correlated with the incidence of leptomeningeal contrast enhancement seen on postcontrast fluid-attenuated inversion recovery (FLAIR) MRI (p = 0.003). Patients with a more pronounced brain barrier dysfunction recovered more slowly and stayed longer in the hospital. CONCLUSIONS The severity of meningeal BBB disturbance can be estimated on postcontrast FLAIR MRI, which may be of diagnostic value in patients with aseptic meningitis.