Capability of differentiating smokers with normal pulmonary function from COPD patients: a comparison of CT pulmonary volume analysis and MR perfusion imaging

Objective

To compare CT volume analysis with MR perfusion imaging in differentiating smokers with normal pulmonary function (controls) from COPD patients.

Methods

Sixty-two COPD patients and 17 controls were included. The total lung volume (TLV), total emphysema volume (TEV) and emphysema index (EI) were quantified by CT. MR perfusion evaluated positive enhancement integral (PEI), maximum slope of increase (MSI), maximum slope of decrease (MSD), signal enhancement ratio (SER) and signal intensity ratio (R_SI) of perfusion defects to normal lung.

Results

There were 19 class I, 17 class II, 14 class III and 12 class IV COPD patients. No differences were observed in TLV, TEV and EI between control and class I COPD. The control was different from class II, III and IV COPD in TEV and EI. The control was different from each class of COPD in R_SI, MSI, PEI and MSD. Differences were found in R_SI between class I and III, I and IV, and II and IV COPD. Amongst controls, MR detected perfusion defects more frequently than CT detected emphysema.

Conclusions

Compared with CT, MR perfusion imaging shows higher potential to distinguish controls from mild COPD and appears more sensitive in identifying abnormalities amongst smokers with normal pulmonary function (controls).

Key Points

? Detailed information is needed to diagnose chronic obstructive pulmonary disease. ? High-resolution CT provides detailed anatomical and quantitative information. ? Magnetic resonance imaging is demonstrating increasing potential in pulmonary function imaging. ? MR perfusion can distinguish mild COPD patients from controls. ? MRI appears more sensitive than CT in identifying early abnormalities amongst controls.     

Quantitative assessment of change in regional disease patterns on serial HRCT of fibrotic interstitial pneumonia with texture-based automated quantification system

Objectives

To evaluate the usefulness of a texture-based automated quantification system (AQS) for evaluating the extent and interval change of regional disease patterns on initial and follow-up high-resolution computed tomographies (HRCTs) of fibrotic interstitial pneumonia (FIP).

Methods

Eighty-nine patients with clinically and/or biopsy confirmed usual interstitial pneumonia (UIP) (n?=?71) and non-specific interstitial pneumonia (NSIP) (n?=?18) were included. An AQS to quantify five disease patterns (ground-glass opacity [GGO], reticular opacity [RO], honeycombing [HC], emphysema [EMPH], consolidation [CONS]) and normal lung was developed. The extent and interval changes of each disease pattern, FS (fibrosis score), TA (total abnormal lung fraction) of entire lung on initial and 1-year follow-up HRCTs were quantified. The agreement between the results of AQS and two readers was assessed. Results of AQS were correlated with forced vital capacity (FVC) and carbon monoxide diffusing capacity (DLco).

Results

The Intraclass correlation coefficient (ICC) study revealed acceptable agreement between visual assessment and AQS (r?=?0.78, 0.66 for HC; 0.76, 0.61 for FS; 0.64, 0.68 for TA, initial and follow-up HRCTs, respectively). Linear regression analysis revealed the extent of HC, TA on initial CT, interval changes of FS contributed negatively to DLco, and interval changes of FS, TA contributed negatively to FVC.

Conclusions

Our AQS is comparable with visual assessment for evaluating the disease extent and the interval changes of FIP on HRCT.

Key Points

? HRCT is widely used to assess fibrotic interstitial pneumonia ? An automated quantification system matched well with visual assessment of HRCT ? Abnormal lung fraction on HRCT correlated with the decrease in diffusion capacity ? Automated quantification of HRCT images is useful in assessing fibrotic interstitial pneumonia     

The diagnostic accuracy of unenhanced MRI in the assessment of joint abnormalities in juvenile idiopathic arthritis

Objectives

To assess the diagnostic accuracy and reliability of MRI without contrast enhancement in the evaluation of JIA knee joint abnormalities.

Methods

JIA patients with clinically active knee involvement were prospectively studied using an 1-T open-bore magnet. MRI features were independently evaluated by two readers using the JAMRIS system. The first reading included unenhanced images, whereas complete image sets were available for the second reading.

Results

Imaging findings from 73 patients were analysed. Agreement between Gd-enhanced (+Gd) and Gd-unenhanced (?Gd) MRI scores of bone marrow changes, cartilage lesions and bone erosions was good concerning sensitivity, specificity, negative predictive value and positive predictive value. Inter-observer agreement was good for both ?Gd and +Gd scores (ICC?=?0.91–1.00, 0.93–1.00, respectively). Regarding the assessment of synovial hypertrophy, specificity of ?Gd was high (0.97), but the sensitivity of unenhanced MRI was only 0.62. Inter-reader agreement for +Gd MRI was ICC?=?0.94; however, omitting post-Gd acquisitions increased inter-reader variation (ICC?=?0.86).

Conclusions

If Gd-enhanced MRI is the reference standard, omitting Gd contrast medium is irrelevant for the assessment of bone marrow changes, cartilage lesions and bone erosions as joint abnormalities in JIA. Omitting intravenous Gd in the MRI assessment of joints in JIA is inadvisable, because it decreases the reliability of detecting synovial disease.

Key Points

? Magnetic resonance imaging is increasingly used to assess juvenile idiopathic arthritis. ? Synovial hypertrophy, a marker of JIA activity, is well shown by MRI. ? Omitting intravenous contrast medium decreases the reliability of synovial hypertrophy scores. ? Bone marrow, cartilage and erosions can be reliably evaluated without contrast enhancement. ? In the evaluation of JIA disease activity, unenhanced MRI is inadvisable.     

How much do GOLD stages reflect CT abnormalities in COPD patients?

Purpose

Severity of chronic obstructive pulmonary disease (COPD) can be graded using the classification released in the Global Initiative for Chronic Obstructive Lung Disease (GOLD) report. Such classification is essentially based on spirometry and does not recognise the role of other measures. The aim of this study was to assess whether the GOLD stages correlate with the extent of pulmonary emphysema and other ancillary computed tomography CT features in a population of smokers with stable COPD.

Materials and methods

Based on clinical assessment and lung-function testing, patients were classified according to the GOLD criteria. CT scans were visually evaluated for extent of emphysema and airway abnormalities.

Results

A total of 43 patients were enrolled. The amount of emphysema was described as minimal in six patients with stage 0, and as moderate in seven patients with stage 0. In stages I and II, the extent of emphysema ranged from minimal to severe, whereas we observed the presence of severe emphysema in most patients in stages III and IV. According to the regression model, only CT emphysema extent independently predicted the GOLD stage (r ²=0.58; p<0.001). The cutoff value of emphysema extent of 31.5% allowed us to distinguish patients with a GOLD stage ≥III.

Conclusions

Although we found a significant correlation between CT emphysema extent and GOLD stages, different percentage of emphysema extent can be observed among each GOLD stage. The upper limit of 31.5% of emphysema extent may indicate a boundary for a clinically worsening status.     

Tomosynthesis for the early detection of pulmonary emphysema: diagnostic performance compared with chest radiography, using multidetector computed tomography as reference

Objectives

To compare the diagnostic performance of tomosynthesis with that of chest radiography for the detection of pulmonary emphysema, using multidetector computed tomography (MDCT) as reference.

Methods

Forty-eight patients with and 63 without pulmonary emphysema underwent chest MDCT, tomosynthesis and radiography on the same day. Two blinded radiologists independently evaluated the tomosynthesis images and radiographs for the presence of pulmonary emphysema. Axial and coronal MDCT images served as the reference standard and the percentage lung volume with attenuation values of ?950 HU or lower (LAA_?950) was evaluated to determine the extent of emphysema. Receiver-operating characteristic (ROC) analysis and generalised estimating equations model were used.

Results

ROC analysis revealed significantly better performance (P < 0.0001) of tomosynthesis than radiography for the detection of pulmonary emphysema. The average sensitivity, specificity, positive predictive value and negative predictive value of tomosynthesis were 0.875, 0.968, 0.955 and 0.910, respectively, whereas the values for radiography were 0.479, 0.913, 0.815 and 0.697, respectively. For both tomosynthesis and radiography, the sensitivity increased with increasing LAA_?950.

Conclusions

The diagnostic performance of tomosynthesis was significantly superior to that of radiography for the detection of pulmonary emphysema. In both tomosynthesis and radiography, the sensitivity was affected by the LAA_?950.

Key Points

? Tomosynthesis showed significantly better diagnostic performance for pulmonary emphysema than radiography. ? Interobserver agreement for tomosynthesis was significantly higher than that for radiography. ? Sensitivity increased with increasing LAA _?950 in both tomosynthesis and radiography. ? Tomosynthesis imparts a similar radiation dose to two projection chest radiography. ? Radiation dose and cost of tomosynthesis are lower than those of MDCT.     

Optimal threshold in CT quantification of emphysema

Objectives

To determine the optimal threshold by quantitatively assessing the extent of emphysema at the level of the entire lung and at the level of individual lobes using a large, diverse dataset of computed tomography (CT) examinations.

Methods

This study comprises 573 chest CT examinations acquired from subjects with different levels of airway obstruction (222 none, 83 mild, 141 moderate, 63 severe and 64 very severe). The extent of emphysema was quantified using the percentage of the low attenuation area (LAA%) divided by the total lung or lobe volume(s). The correlations between the extent of emphysema, and pulmonary functions and the five-category classification were assessed using Pearson and Spearman’s correlation coefficients, respectively. When quantifying emphysema using a density mask, a wide range of thresholds from ?850 to ?1,000 HU were used.

Results

The highest correlations of LAA% with the five-category classification and PFT measures ranged from ?925 to ?965 HU for each individual lobe and the entire lung. However, the differences between the highest correlations and those obtained at ?950 HU are relatively small.

Conclusion

Although there are variations in the optimal cut-off thresholds for individual lobes, the single threshold of ?950 HU is still an acceptable threshold for density-based emphysema quantification.

Key Points

? CT is widely used to assess the severity of emphysema ? Density mask technique helps clinicians assess the extent of emphysema with CT ? A standardised cut-off for density mask analysis at lobe level is desirable ? ?950 HU is acceptable for density-based emphysema quantification at the lobar level     

Dual-energy CT perfusion and angiography in chronic thromboembolic pulmonary hypertension: diagnostic accuracy and concordance with radionuclide scintigraphy

Objectives

To evaluate the diagnostic accuracy of dual-energy computed tomography (DECT) perfusion and angiography versus ventilation/perfusion (V/Q) scintigraphy in chronic thromboembolic pulmonary hypertension (CTEPH), and to assess the per-segment concordance rate of DECT and scintigraphy.

Methods

Forty consecutive patients with proven pulmonary hypertension underwent V/Q scintigraphy and DECT perfusion and angiography. Each imaging technique was assessed for the location of segmental defects. Diagnosis of CTEPH was established when at least one segmental perfusion defect was detected by scintigraphy. Diagnostic accuracy of DECT perfusion and angiography was assessed and compared with scintigraphy. In CTEPH patients, the per-segment concordance between scintigraphy and DECT perfusion/angiography was calculated.

Results

Fourteen patients were diagnosed with CTEPH and 26 with other aetiologies. DECT perfusion and angiography correctly identified all CTEPH patients with sensitivity/specificity values of 1/0.92 and 1/0.93, respectively. At a segmental level, DECT perfusion showed moderate agreement (κ?=?0.44) with scintigraphy. Agreement between CT angiography and scintigraphy ranged from fair (κ?=?0.31) to slight (κ?=?0.09) depending on whether completely or partially occlusive patterns were considered, respectively.

Conclusions

Both DECT perfusion and angiography show satisfactory performance for the diagnosis of CTEPH. DECT perfusion is more accurate than angiography at identifying the segmental location of abnormalities.

Key Points

? Chronic thromboembolic pulmonary hypertension (CTEPH) is potentially treatable by surgery. ? Dual-energy computed tomography (DECT) allows angiography and perfusion using a single acquisition. ? Both DECT perfusion and angiography showed satisfactory diagnostic performance in CTEPH. ? DECT perfusion was more accurate than angiography in identifying segmental abnormalities.     

Interobserver agreement in breast radiological density attribution according to BI-RADS quantitative classification

Purpose

The authors sought to assess interobserver agreement in classifying mammography density according to quantitative Breast Imaging Reporting and Data System (BI-RADS) criteria.

Materials and methods

Six expert mammography readers were tested on a set of 100 mammograms. Interobserver agreement was determined according to the kappa statistic, adjusting for chance agreement, on a four-category (D1 vs. D2 vs. D3 vs. D4) or two-category (D1?C2 vs. D3?C4) basis. Agreement with a panel of 12 readers who had been tested on the same set in a previous study was also assessed.

Results

The six readers showed good agreement when compared in pairs [agreement on a four-category basis was substantial (kappa=0.60?C0.80) for 13 pairs and almost perfect (kappa>0.80) for two pairs); agreement on a two-category basis was substantial for 12 pairs and almost perfect for three pairs) or compared with the panel (on a four-category basis, agreement was substantial for five of six readers and almost perfect for one; on a two-category basis, agreement was substantial for all readers).

Conclusions

In agreement with previous studies, visual classification of mammography density according to BI-RADS quantitative criteria was highly reproducible among readers; nevertheless, attribution to the ??dense breast?? (BI-RADS D3?C4) category, which might be adopted as a determinant of different screening protocols (such as adjunct ultrasonography or yearly interval) varied among readers (range 6?C15%). Controlled studies should be performed comparing visual with computer-density category attribution, the latter possibly being a better alternative due to its absolute reproducibility.     

Comparison between 2D and 3D computed tomography evaluation of glenoid bone defect in unilateral anterior gleno-humeral instability

Purpose

This study evaluated the agreement between 2D and 3D computed tomography (CT) measurements in identifying the size and type of glenoid-bone defect in anterior glenohumeral instability.

Materials and methods

One hundred patients affected by unilateral anterior glenohumeral instability underwent a CT of both shoulders. Images were processed with both 2D [multiplanar reconstruction (MPR)] and 3D [volumerendering (VR)] methods. The area of the missing glenoid was calculated in comparison with the healthy glenoid and expressed as a percentage. Agreement between the two measurements was assessed according to the Bland-Altman method; a 5% mean difference was considered as clinically relevant.

Results

Analysis of agreement between MPR and VR measurements of the percentage of missing glenoid showed a mean difference equal to 0.62%±1.96%. Percent agreement between the two measurements in detecting the presence of bone defect was 97% (p<0.0001). Percent agreement between the two measurements in discriminating the type of bone defect was 97% (p<0.0001).

Conclusions

Agreement between 2D (MPR) and 3D (VR) CT measurements to identify the size and type of glenoid-bone defect in anterior glenohumeral instability was so high that the two measurements can be considered interchangeable.     

The effect of iterative reconstruction on computed tomography assessment of emphysema, air trapping and airway dimensions

Objectives

To determine the influence of iterative reconstruction (IR) on quantitative computed tomography (CT) measurements of emphysema, air trapping, and airway wall and lumen dimensions, compared to filtered back-projection (FBP).

Methods

Inspiratory and expiratory chest CTs of 75 patients (37 male, 38 female; mean age 64.0?±?5.7?years) were reconstructed using FBP and IR. CT emphysema, CT air trapping and airway dimensions of a segmental bronchus were quantified using several commonly used quantification methods. The two algorithms were compared using the concordance correlation coefficient (p _c) and Wilcoxon signed rank test.

Results

Only the E/I-ratio_MLD as a measure of CT air trapping and airway dimensions showed no significant differences between the algorithms, whereas all CT emphysema and the other CT air trapping measures were significantly different at IR when compared to FBP (P?Conclusion The evaluated IR algorithm significantly influences quantitative CT measures in the assessment of emphysema and air trapping. However, the E/I-ratio_MLD as a measure of CT air trapping, as well as the airway measurements, is unaffected by this reconstruction method. Quantitative CT of the lungs should be performed with careful attention to the CT protocol, especially when iterative reconstruction is introduced.

Key Points

? New techniques in CT allow numerous quantitative measurements of lung function. ? Iterative reconstruction influences quantitative CT measurements of emphysema and air trapping. ? Expiratory-to-inspiratory ratio of mean lung density and airway measurements are unaffected by iterative reconstruction. ? Quantitative lung-CT should be performed with careful attention to the CT protocol.     

Evaluation of micro-CT for emphysema assessment in mice: comparison with non-radiological techniques

Objectives

To define the potential, limitations and synergies of micro-CT and other non-radiological techniques for the quantification of emphysema and related processes in mice, by performing a complete characterization of the elastase-induced emphysema model.

Materials and methods

Ninety A/J mice (45 treated and 45 controls) were studied at different time points using breath-hold gated micro-CT, functional test parameters, RT-PCR for RNA cytokine expression, Luminex technology for cytokine plasma concentration and histomorphometry.

Results

Both histomorphometry and micro-CT imaging reflect rapid initial emphysema progression followed by steady-state development at decreasing rates. Cytokine measurements reveal an acute inflammatory response within the first 24?h that disappears after the first week. Limited systemic effect was observed based on plasma cytokine concentration. Lung compliance decreases during the acute inflammation phase and increases afterwards.

Conclusion

Histomorphometry is the most sensitive technique since it detects airspace enlargement before the other methods (1?h after treatment). Micro-CT correlates well with histology (r2?=?0.63) proving appropriate for longitudinal studies. Functional test parameters do not necessarily correlate with the extent of emphysema, as they can be influenced by acute inflammation. Finally, cytokine measurements correlate with the presence of inflammation in histology but not with emphysema.     

Monitoring therapeutic effects in experimental stroke by serial USPIO-enhanced MRI

Objectives

This study sought to evaluate whether the therapeutic effects of an anti-inflammatory drug such as minocycline could be monitored by serial ultrasmall superparamagnetic particles of iron oxide (USPIO)-enhanced MRI in experimental stroke.

Methods

Mice received a three-dose minocycline treatment (n?=?12) or vehicle (n?=?12) after permanent middle cerebral artery occlusion. USPIOs were administered 5?h post-surgery. MRI was performed before, 24?h and 48?h post-USPIO administration. MRI endpoints were the extent of signal abnormalities on R2 maps (=1/T2) and quantitative R2 changes over time (?R2). Post-mortem brains were prepared either for immunohistology (n?=?16) or for iron dosage (n?=?8).

Results

As expected, treatment with minocycline significantly reduced infarct size, blood-brain barrier permeability and F4/80 immunostaining for microglia/macrophages. Areas of R2 maps?>?35?ms^-1 also appeared significantly decreased in minocycline-treated mice (ANOVA for repeated measures, P?=?0.017). There was a fair correlation between these areas and the amount of iron in the brain (R²?=?0.69, P?=?0.010), but no significant difference in ?R2 was found between the two groups.

Conclusions

This study showed that the extent of signal abnormalities on R2 maps can be used as a surrogate marker to detect minocycline effects in a murine experimental model of stroke.

Key Points

? Ultrasmall superparamagnetic particles of iron oxide offer new avenues for MRI research ? Treatment of the inflammatory response following ischaemic stroke is currently undergoing evaluation. ? Minocycline treatment significantly reduced areas of signal abnormalities on USPIO-enhanced MRI. ? These areas correlated with the amount of iron in the brain. ? Thus USPIO-enhanced MRI might provide a surrogate marker to monitor treatment     

Standard 1.5-T MRI of endometrial carcinomas: modest agreement between radiologists

Objectives

To evaluate pelvic magnetic resonance imaging (MRI) interobserver agreement for the detection of deep myometrial invasion, cervical stroma invasion and lymph node metastases in endometrial carcinoma patients in relation to surgical staging.

Methods

Fifty-seven patients with histologically confirmed endometrial carcinoma were prospectively included in a study of preoperative 1.5-T MRI. Four radiologists, blinded to patient data, independently reviewed the images for the presence of deep myometrial invasion, cervical stroma invasion and lymph node metastases. Kappa coefficients for interobserver agreement and diagnostic performances for each observer were calculated using final surgical staging results (FIGO 09) as reference standard.

Results

Overall agreement among all observers was moderate for cervical stroma invasion (κ?=?0.50 [95% CI 0.27–0.73]) and lymph node metastases (κ?=?0.56 [0.09–0.80]) and fair for deep myometrial invasion (κ?=?0.39 [0.26–0.55]). Sensitivity (specificity) values for the four observers were 72–92% (44–63%) for deep myometrial invasion, 38–63% (82–94%) for cervical stroma invasion and 25–38% (90–100%) for lymph node metastases.

Conclusions

Conventional MRI showed only modest interobserver agreement and diagnostic accuracy for detection of deep myometrial invasion, cervical stroma invasion and lymph node metastases. Improved methods are needed for preoperative imaging in the staging of endometrial carcinomas.

Key Points

? MRI is an important tool for preoperative endometrial cancer staging. ? Staging agreement based on pelvic MRI was modest among different observers. ? Preoperative MRI alone was suboptimal in identifying high-risk patients. ? Improved imaging and biomarkers may refine preoperative risk stratification in endometrial cancer.     

Diffusion tensor imaging and tractography to evaluate sacral nerve root abnormalities in endometriosis-related pain: A pilot study

Objective

To prospectively evaluate microstructural abnormalities in sacral nerve roots in women affected by chronic pelvic pain associated with endometriosis.

Methods

We enrolled 30 women with an ultrasound diagnosis of endometriosis and moderate-severe chronic pelvic pain; 10 age-matched healthy women comprised the control group. All subjects underwent 3 T magnetic resonance imaging (MRI), including diffusion tensor imaging (DTI); the sacral roots were reconstructed by post-processing the DTI data with dedicated software. Mean fractional anisotropy (FA) values in the S1, S2 and S3 roots were quantified. Analysis of FA values was performed by two radiologists in order to evaluate the interobserver agreement.

Results

The sacral nerve roots in healthy subjects were clearly visualised. Most of the patients with endometriosis displayed abnormalities of S1, S2 and S3 bilaterally at tractography, including an irregular and disorganised appearance. FA values in the S1, S2 and S3 roots were significantly lower in patients than in controls (P?<?0.0001, <0.05 and <0.02, respectively) for both observers. No significant difference was found between observers.

Conclusion

DTI with tractography is a non-invasive means of detecting changes in the microarchitecture of the sacral nerve roots. It can qualitatively and quantitatively reveal sacral root abnormalities in patients with endometriosis-associated pain.

Key Points

? MRI is increasingly used for endometriosis and chronic pelvic pain (CPP). ? Magnetic resonance tractography can demonstrate microarchitectural abnormalities in sacral nerve roots. ? Tractography shows altered microstructure of sacral roots affected by endometriosis and CPP. ? S1–S3 fractional anisotropy values are lower in endometriosis than in healthy women. ? Sacral nerve root alteration may explain the nature of endometriosis-related CPP.     

Morphological measurements in computed tomography correlate with airflow obstruction in chronic obstructive pulmonary disease: systematic review and meta-analysis

Objectives

To determine the correlation between CT measurements of emphysema or peripheral airways and airflow obstruction in chronic obstructive pulmonary disease (COPD).

Methods

PubMed, Embase and Web of Knowledge were searched from 1976 to 2011. Two reviewers independently screened 1,763 citations to identify articles that correlated CT measurements to airflow obstruction parameters of the pulmonary function test in COPD patients, rated study quality and extracted information. Three CT measurements were accessed: lung attenuation area percentage?1 %pred) and FEV₁ divided by the forced volume vital capacity.

Results

Seventy-nine articles (9,559 participants) were included in the systematic review, demonstrating different methodologies, measurements and CT airflow obstruction correlations. There were 15 high-quality articles (2,095 participants) in the meta-analysis. The absolute pooled correlation coefficients ranged from 0.48 (95?% CI, 0.40 to 0.54) to 0.65 (0.58 to 0.71) for inspiratory CT and 0.64 (0.53 to 0.72) to 0.73 (0.63 to 0.80) for expiratory CT.

Conclusions

CT measurements of emphysema or peripheral airways are significantly related to airflow obstruction in COPD patients. CT provides a morphological method to investigate airway obstruction in COPD.

Key Points

? Computed tomography is widely performed in patients with chronic obstructive pulmonary disease (COPD) ? CT provides quantitative morphological methods to investigate airflow obstruction in COPD ? CT measurements correlate significantly with the degree of airflow obstruction in COPD ? Expiratory CT measurements correlate more strongly with airflow obstruction than inspiratory CT ? Low-dose CT decreases the radiation dose for diagnosis and quantitative emphysema evaluation     

Anterior temporal lobe white matter abnormal signal (ATLAS) as an indicator of seizure focus laterality in temporal lobe epilepsy: comparison of double inversion recovery, FLAIR and T2W MR imaging

Objectives

To investigate the diagnostic capability of anterior temporal lobe white matter abnormal signal (ATLAS) for determining seizure focus laterality in temporal lobe epilepsy (TLE) by comparing different MR sequences.

Methods

This prospective study was approved by the institutional review board and written informed consent was obtained. Three 3D sequences (double inversion recovery (DIR), fluid-attenuated inversion recovery (FLAIR) and T2-weighted imaging (T2WI)) and two 2D sequences (FLAIR and T2WI) were acquired at 3?T. Signal changes in the anterior temporal white matter of 21 normal volunteers were evaluated. ATLAS laterality was evaluated in 21 TLE patients. Agreement of independent evaluations by two neuroradiologists was assessed using ?? statistics. Differences in concordance between ATLAS laterality and clinically defined seizure focus laterality were analysed using McNemar??s test with multiple comparisons.

Results

Pre-amygdala high signals (PAHS) were detected in all volunteers only on 3D-DIR. Inter-evaluator agreement was moderate to almost perfect for each sequence. Correct diagnosis of seizure laterality was significantly more frequent on 3D-DIR than on any other sequences (P????0.031 for each evaluator).

Conclusions

The most sensitive sequence for detecting ATLAS laterality was 3D-DIR. ATLAS laterality on 3D-DIR can be a good indicator for determining seizure focus localization in TLE.

Key Points

? Magnetic resonance imaging is widely used to investigate temporal lobe epilepsy. ? Numerous MR sequences can show anterior temporal lobe white matter abnormal signal. ? ATLAS on 3D-DIR can frequently indicate seizure focus laterality in TLE. ? 3D-DIR is more sensitive about ATLAS laterality than T2WI or FLAIR.     

Diagnostic accuracy of post-mortem MRI for thoracic abnormalities in fetuses and children

Objectives

To compare the diagnostic accuracy of post-mortem magnetic resonance imaging (PMMR) specifically for non-cardiac thoracic pathology in fetuses and children, compared with conventional autopsy.

Methods

Institutional ethics approval and parental consent was obtained. A total of 400 unselected fetuses and children underwent PMMR before conventional autopsy, reported blinded to the other dataset.

Results

Of 400 non-cardiac thoracic abnormalities, 113 (28 %) were found at autopsy. Overall sensitivity and specificity (95 % confidence interval) of PMMR for any thoracic pathology was poor at 39.6 % (31.0, 48.9) and 85.5 % (80.7, 89.2) respectively, with positive predictive value (PPV) 53.7 % (42.9, 64.0) and negative predictive value (NPV) 77.0 % (71.8, 81.4). Overall agreement was 71.8 % (67.1, 76.2). PMMR was most sensitive at detecting anatomical abnormalities, including pleural effusions and lung or thoracic hypoplasia, but particularly poor at detecting infection.

Conclusions

PMMR currently has relatively poor diagnostic detection rates for the commonest intra-thoracic pathologies identified at autopsy in fetuses and children, including respiratory tract infection and diffuse alveolar haemorrhage. The reasonable NPV suggests that normal thoracic appearances at PMMR exclude the majority of important thoracic lesions at autopsy, and so could be useful in the context of minimally invasive autopsy for detecting non-cardiac thoracic abnormalities.

Key Points

? PMMR has relatively poor diagnostic detection rates for common intrathoracic pathology ? The moderate NPV suggests that normal PMMR appearances exclude most important abnormalities ? Lung sampling at autopsy remains the “gold standard” for pulmonary pathology     

Evaluating the agreement between tumour volumetry and the estimated volumes of tumour lesions using an algorithm

Objectives

To evaluate the agreement between tumour volume derived from semiautomated volumetry (SaV) and tumor volume defined by spherical volume using longest lesion diameter (LD) according to Response Evaluation Criteria In Solid Tumors (RECIST) or ellipsoid volume using LD and longest orthogonal diameter (LOD) according to World Health Organization (WHO) criteria.

Materials and methods

Twenty patients with metastatic colorectal cancer from the CIOX trial were included. A total of 151 target lesions were defined by baseline computed tomography and followed until disease progression. All assessments were performed by a single reader. A variance component model was used to compare the three volume versions.

Results

There was a significant difference between the SaV and RECIST-based tumour volumes. The same model showed no significant difference between the SaV and WHO-based volumes. Scatter plots showed that the RECIST-based volumes overestimate lesion volume. The agreement between the SaV and WHO-based relative changes in tumour volume, evaluated by intraclass correlation, showed nearly perfect agreement.

Conclusions

Estimating the volume of metastatic lesions using both the LD and LOD (WHO) is more accurate than those based on LD only (RECIST), which overestimates lesion volume. The good agreement between the SaV and WHO-based relative changes in tumour volume enables a reasonable approximation of three-dimensional tumour burden.

Key Points

? Tumour response in patients undergoing chemotherapy is assessed using CT images ? Measurements are based on RECIST (unidimensional)-based or WHO (bidimensional)-based criteria ? We calculated tumour volume from bidimensional target lesion measurements ? This formula provides good tumour volume approximation, based on semiautomated volumetry     

Aiming for a shorter rheumatoid arthritis MRI protocol: can contrast-enhanced MRI replace T2 for the detection of bone marrow oedema?

Purpose

To determine whether T1 post-gadolinium chelate images (T1Gd) can replace T2-weighted images (T2) for evaluating bone marrow oedema (BME), thereby allowing a shorter magnetic resonance imaging (MRI) protocol in rheumatoid arthritis (RA).

Material and methods

In 179 early arthritis patients and 43 advanced RA patients, wrist and metacarpophalangeal joints were examined on a 1.5-T extremity MRI system with a standard protocol (coronal T1, T2 fat-saturated and coronal and axial T1 fat-saturated after Gd). BME was scored according to OMERACT RAMRIS by two observers with and without T2 images available. Agreement was assessed using intraclass correlation coefficients (ICCs) for semi-quantitative scores and test characteristics with T2 images as reference.

Results

Agreement between scores based on T2 and T1Gd images was excellent ICC (0.80–0.99). At bone level, sensitivity and specificity of BME on T1Gd compared to T2 were high for both patient groups and both readers (all ≥80 %).

Conclusion

T1Gd and T2 images are equally suitable for evaluating BME. Because contrast is usually administered to assess (teno)synovitis, a short MRI protocol of T1 and T1Gd is sufficient in RA.

Key Points

? Bone marrow oedema scores are equal on T2 and T1-Gd-chelate enhanced sequences. ? Agreement between scores based on T2 and T1-Gd-chelate images was excellent. ? Sensitivity and specificity for presence of bone marrow oedema were high. ? A short protocol without T2 images suffices in rheumatoid arthritis patients.