Effects of left ventricular size on the accuracy of diastolic parameters derived from myocardial perfusion SPECT: comparison with tissue Doppler echocardiography

Background

Impaired left ventricular (LV) diastolic function is a sensitive and early sign of myocardial ischemia. We evaluated the effects of LV size on the accuracy of diastolic parameters derived from SPECT.

Methods

The study population consisted of 151 patients with known or suspected coronary artery disease who underwent both SPECT and transthoracic echocardiography. Peak filling rate (PFR), one-third mean filling rate (1/3 MFR) and the ratio of time to PFR to the RR interval (TPFR/RR) were calculated by quantitative gated SPECT. Peak early mitral annular velocity (e′) was used as the reference standard of LV diastolic function.

Results

There were 43 patients with end-systolic volume (ESV) of ≤10 ml, 43 patients with ESV of 11–20 ml and 65 patients with ESV of >20 ml. There were significant differences in PFR (p < 0.001), 1/3 MFR (p < 0.001) or TPFR/RR (p = 0.01) among the 3 groups. These diastolic parameters were increased with decreased LV size. In overall patients, PFR (r = 0.24, p = 0.003) and 1/3 MFR (r = 0.31, p < 0.001) were positively, and TPFR/RR (r = ?0.23, p = 0.004) was inversely correlated with e′. Multivariate linear regression analyses showed that male gender (β = ?0.14, p = 0.07; β = ?0.16, p = 0.04), ESV (β = ?0.63, p < 0.001; β = ?0.45, p < 0.001) and e′ (β = 0.36, p < 0.001; β = 0.40, p < 0.001) were significant factors associated with PFR or 1/3 MFR. Multivariate linear regression analysis also showed that ESV (β = ?0.17, p = 0.03) and e′ (β = ?0.21, p = 0.01) were significant factors associated with TPFR/RR.

Conclusions

Our data suggest that PFR, 1/3 MFR and TPFR/RR derived from SPECT are correlated with e′ as the reference standard of LV diastolic function, but are overestimated in small-sized heart. LV size should be taken into consideration when interpreting these diastolic parameters.

     

The experimental design of postmortem studies: the effect size and statistical power

Purpose

The aim is of this study was to show the poor statistical power of postmortem studies. Further, this study aimed to find an estimate of the effect size for postmortem studies in order to show the importance of this parameter. This can be an aid in performing power analysis to determine a minimal sample size.

Methods

GPower was used to perform calculations on sample size, effect size, and statistical power. The minimal significance (α) and statistical power (1 ? β) were set at 0.05 and 0.80 respectively. Calculations were performed for two groups (Student’s t-distribution) and multiple groups (one-way ANOVA; F-distribution).

Results

In this study, an average effect size of 0.46 was found (n = 22; SD = 0.30). Using this value to calculate the statistical power of another group of postmortem studies (n = 5) revealed that the average statistical power of these studies was poor (1 ? β < 0.80).

Conclusion

The probability of a type-II error in postmortem studies is considerable. In order to enhance statistical power of postmortem studies, power analysis should be performed in which the effect size found in this study can be used as a guideline.

     

Ultra-low-dose CT coronary angiography using 128-slice dual source CT with low concentration contrast agent: initial experience

Purpose

To optimize and evaluate an ultra-low-dose (ULD) technique for CT coronary angiography (CTCA).

Materials and methods

Eighty-two patients were randomly divided into two groups. ULD and routine CTCA were performed in groups A and B. Image quality, radiation dose and contrast agent were evaluated.

Results

The effective dose (ED) was 0.20 ± 0.01 mSv for the ULD technique, a decrease of 87% (t = ? 21.182, P < 0.001) compared with the control group. The total iodine content was 8.10 ± 0 g, a decrease of 62% (t = ? 73.458, P < 0.001) compared with 21.10 ± 1.15 g for the control group. The assessment rates for both groups were the same (99.26 vs 99.64%, χ ²  = 0.727, P = 0.394). The contrast-to-noise ratio was 19.31 ± 7.95 for group A and 20.73 ± 5.07 for group B: the difference was not statistically significant (t = ? 1.678, P = 0.095).

Conclusion

Using an ultra-low radiation dose and contrast agent technique, while maintaining an assessable image and improving the safety of the medical examination, was a feasible and reliable method for CTCA.

     

Can we predict the size of frequently used autografts in ACL reconstruction?

Purpose

This study presents a method to measure the size of quadriceps, patellar tendon and hamstring autografts using preoperative magnetic resonance imaging (MRI).

Methods

Sixty-two subjects with a mean age of 25 ± 10 years who underwent ACL surgery between 2011 and 2014 were included. Patient anthropometric data were recorded for all subjects. During surgery, the respective autograft was harvested and measured using commercially available graft sizers. MRI measurements were performed by two raters, who were blinded to the intra-operative measurements.

Results

The inter- and intra-rater reliability was ≥0.8 for all MRI measurements. The intra-class correlation coefficient between the MRI measurement of the graft and the actual size of the harvested graft was 0.639. There were significant correlations between quadriceps tendon thickness and height (r = 0.3, p < 0.03), weight (r = 0.3, p < 0.01), BMI (r = 0.3, p < 0.04) and gender (r = ?0.4, p < 0.002) and patellar tendon thickness and height (r = 0.4, p < 0.01), weight (r = 0.3, p < 0.01) and gender (r = ?0.4, p < 0.012).

Conclusion

Preoperative MRI measurements of quadriceps, patellar tendon and hamstring graft size are highly reliable with moderate-to-good accuracy. Significant correlations between patient anthropometric data and the thicknesses of the quadriceps and patellar tendons were observed. Obtaining this information can be useful for preoperative planning and to help counsel patients on appropriate graft choices prior to surgery.

Level of evidence

III.

     

Breast dose reduction for chest CT by modifying the scanning parameters based on the pre-scan size-specific dose estimate (SSDE)

Objective

To investigate the usefulness of modifying scanning parameters based on the size-specific dose estimate (SSDE) for a breast-dose reduction for chest CT.

Materials and methods

We scanned 26 women with a fixed volume CT dose index (CTDI_vol) (15 mGy) and another 26 with a fixed SSDE (15 mGy) protocol (protocol 1 and 2, respectively). In protocol 2, tube current was calculated based on the patient habitus obtained on scout images. We compared the mean breast dose and the inter-patient breast dose variability and performed linear regression analysis of the breast dose and the body mass index (BMI) of the two protocols.

Results

The mean breast dose was about 35 % lower under protocol 2 than protocol 1 (10.9 mGy vs. 16.8 mGy, p?<?0.01). The inter-patient breast dose variability was significantly lower under protocol 2 than 1 (1.2 mGy vs. 2.5 mGy, p?<?0.01). We observed a moderate negative correlation between the breast dose and the BMI under protocol 1 (r?=?0.43, p?<?0.01); there was no significant correlation (r?=?0.06, p?=?0.35) under protocol 2.

Conclusion

The SSDE-based protocol achieved a reduction in breast dose and in inter-patient breast dose variability.

Key Points

? CT scan parameters can be modified based on the pre-scan SSDE.? The pre-scan SSDE is useful for a breast dose reduction.? The fixed SSDE protocol reduced individual variations in the breast dose.

     

MR arthrography of the hip: evaluation of isotropic 3D intermediate-weighted FSE and hybrid GRE T1-weighted sequences

Purpose

To compare the diagnostic performance of three-dimensional (3D) intermediate-weighted FSE (IW-3D) and 3D hybrid T1-weighted sequences (Hy-3D) and 2D fast-spin-echo sequences (FSE) in diagnosing chondral and labral lesions at 1.5 Tesla hip MR arthrography (MRA).

Materials and methods

Institutional review board approval was obtained and informed consent was waived. Ninety-two consecutive patients were evaluated. Chondral and labral lesions were retrospectively and independently evaluated by two radiologists. Intra-operative findings were used as the reference standard (arthroscopy = 73, open surgery = 19). Sensitivity (Se), specificity (Sp), and accuracy (Acc) values that obtained were compared using McNemar test. A value of p < 0.05 was considered statistically significant. Inter-observer agreement was calculated using kappa statistics.

Results

Surgeons revealed 81 labrum and 44 chondral lesions, respectively. The highest Se, Sp, and Acc for Reader 1 were 96.3, 90.9, and 95.6%, respectively, in evaluating labral lesions (by reading 2D data set) and 90.9, 100, and 95.7% in evaluating chondral lesions (by reading IW-3D images). The highest Se, Sp, and Acc for Reader 2 were 93.8, 81.8, and 92.4% in evaluating labral lesions (using 2D images) and 88.6, 97.9, and 93.5%, respectively, in evaluating chondral lesions (using Hy-3D). The difference of diagnostic accuracy achieved was not significant (p > 0.05). A near-perfect inter-observer agreement was achieved by reading 2D data set (k = 0.88) and Hy-3D (k = 0.83) and IW-3D (k = 0.85).

Conclusions

At 1.5 Tesla hip MRA, the accuracy of IW-3D and Hy-3D images was not significantly higher than the 2D sequences in evaluating acetabular labrum and chondral lesions.

     

Correlation between voxel-wise enhancement parameters on DCE-MRI and pathological prognostic factors in invasive breast cancers

Purpose

To investigate the correlation between enhancement parameters on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and pathologic prognostic factors in invasive breast cancers (BCs).

Materials and methods

A total of 25 invasive BCs were included: 22 invasive ductal, 2 invasive lobular and 1 invasive mucinous. The tumor volume was segmented using a semi-automatic software (Olea Sphere). The following voxel-wise enhancement parameters were extracted: (1) time to peak enhancement; (2) signal intensity at peak (SIP); (3) peak enhancement percentage (PEP); (4) post-initial enhancement percentage (PIEP). The following pathological prognostic factors were considered for potential correlation: tumor (pT) and nodal (pN) stage, grading, perivascular/perineural invasion, estrogen/progesterone receptor status, Ki-67 proliferation, and HER2 expression. Spearman and Pearson correlation coefficients were calculated according with type of variable and data distribution.

Results

Tumor volume was 2.8 ± 2.0 cm³ (mean ± standard deviation [SD]). Mean SIP correlated with pT (ρ = 0.424, p = 0.035); mean PEP correlated with HER2 overexpression (? = 0.471, p = 0.017) and pT (ρ = 0.449, p = 0.024). The percentage of voxels with fast PEP directly correlated with pT (ρ = 0.482, p = 0.015) and pN (ρ = 0.446, p = 0.026), while the percentage of voxels with slow PEP inversely correlated with pT (ρ = ?0.421, p = 0.039) and pN (ρ = ?0.481, p = 0.015). Segmentation time was 14.6 ± 1.3 min (mean ± SD).

Conclusion

In invasive BCs, DCE-MRI voxel-wise enhancement parameters correlated with HER2, pT, and pN.

     

Optimal load for the muscle power profile of prone bench pull in Brazilian Jiu-Jitsu athletes

Background

No studies were observed optimal intensity loads for the muscle power performance during prone bench pull exercise in Brazilian Jiu-Jitsu athletes (BJJ) and this exercise is more similar with grip technics.

Purpose

To identify the optimal intensity for the muscle power performance variables during PBP exercise in BJJ athletes.

Methods

Fifteen athletes (25.5 ± 4.9 years; 65.6 ± 12.2 kg; 177.5 ± 4.7 cm) performed PBP at 30, 40, 50 and 60% of one repetition maximum (1RM) in a random order. The mean power (MP), mean velocity (MV), mean propulsive power (MPP) and mean propulsive velocity (MPV) were determined by measuring the barbell displacement by a linear encoder.

Results

In all power performance variables, higher power output was observed at 40 and 50% 1RM when compared to 30 and 60% 1RM (MP: F = 29.07; p < 0.001; MV: F = 40.80; p < 0.001; MPP: F = 53.69; p = 0.003; MPV: F = 166.2; p > 0.001). Additionally, it was observed higher MPP at 50% 1RM when compared to 40% 1RM (F = 55.23; p < 0.001). The polynomial adjustment indicated that the optimal intensity load for producing highest power performance ranged from 45 to 50% 1RM (R ² = 0.938–0.989) across all variables.

Conclusion

The loads between 45 and 50% 1RM produced the optimal muscle power performance during PBP exercise in BJJ athletes.

     

Whole body MRI with qualitative and quantitative analysis of DWI for assessment of bone marrow involvement in lymphoma

Aim

Our study aimed to investigate the role of qualitative and quantitative whole body MRI with DWI for assessment of bone marrow involvement (BMI) in newly diagnosed lymphoma using FDG PET–CT and bone marrow biopsy (BMB) as reference standard.

Materials and methods

We retrospectively evaluated 56 patients with newly diagnosed lymphoma (21 Hodgkin’s lymphoma and 35 non-Hodgkin’s lymphoma) who underwent random unilateral BMB, FDG PET–CT and Wb-MRI-DWI for initial staging. In a patient-based analysis, results of Wb-MRI-DWI were compared with FDG PET–CT and BMB. For quantitative analysis, mean ADC values of posterior iliac crest were correlated with BMI and bone marrow cellularity.

Results

WB-MR-DWI obtained excellent concordance with FDG PET–CT both in HL (k = 1.000; 95% CI 1.000–1.000) and in DLBCL (k = 1.000; 95% CI 1.000–1.000). In other NHL, WB-MRI-DWI obtained a good correlation with BMB (k = 0.611; 95% CI 0.295–0.927) while FDG PET–CT had poor concordance (k = 0.067; 95% CI 0.372–0.505). WB-MR-DWI has no false negative errors but 4 false positive results consisting in focal lesions consensually reported by FDG PET–CT and resolved after therapy. No significant correlation between ADC mean value and BMI was found (p = 0.0586).

Conclusion

Our data suggest that Wb-MRI-DWI is a valid technique for BMI assessment in lymphoma patients, thanks to its excellent concordance with FDG PET–CT and good concordance with BMB (superior than FDG PET–CT). If further investigations will confirm our results on larger patient groups, it could become a useful tool in the clinical workup.

     

Quantitative ultrasound mapping of regional variations in shear wave speeds of the aging Achilles tendon

Objectives

Evaluate the effects of aging on healthy Achilles tendon and aponeurosis shear wave speed (SWS), a quantitative metric which reflects tissue elasticity.

Methods

Shear wave elastography was used to measure spatial variations in Achilles tendon SWS in healthy young (n?=?15, 25?±?4 years), middle-aged (n?=?10, 49?±?4 years) and older (n?=?10, 68?±?5 years) adults. SWS was separately measured in the free Achilles tendon, soleus aponeurosis and gastrocnemius aponeurosis in resting (R), stretched (dorsiflexed 15° from R) and slack (plantarflexed 15° from R) postures.

Results

SWS significantly increased with stretch and varied with age in all tendon regions. Slack free tendon SWS was significantly higher in older adults than young adults (p?=?0.025). However, stretched soleus aponeurosis SWS was significantly lower in older adults than young adults (p?=?0.01). Stretched gastrocnemius aponeurosis SWS was significantly lower in both middle-aged (p?=?0.003) and older (p?=?0.001) adults, relative to younger adults.

Conclusion

These results suggest that aging alters spatial variations in Achilles tendon elasticity, which could alter deformations within the triceps surae muscle–tendon units, thus affecting injury potential. The observed location- and posture-dependent variations highlight the importance of controlling ankle posture and imaging location when using shear wave approaches clinically to evaluate tendon disorders.

Key Points

? Shear wave elastography shows promise as a clinical quantitative ultrasound-based technique.? Aging induces location-dependent changes in Achilles tendon shear wave speed.? Spatial and postural dependence necessitates careful integration of this approach clinically.

     

Comparative evaluation of the algorithms for parametric mapping of the novel myocardial PET imaging agent <Superscript>18</Superscript>F-FPTP

Objective

(¹⁸F-fluoropentyl)triphenylphosphonium salt (¹⁸F-FPTP) is a new promising myocardial PET imaging tracer. It shows high accumulation in cardiomyocytes and rapid clearance from liver. We performed compartmental analysis of ¹⁸F-FPTP PET images in rat and evaluated two linear analyses: linear least-squares (LLS) and a basis function method (BFM) for generating parametric images. The minimum dynamic scan duration for kinetic analysis was also investigated and computer simulation undertaken.

Methods

¹⁸F-FPTP dynamic PET (18 min) and CT images were acquired from rats with myocardial infarction (MI) (n = 12). Regions of interest (ROIs) were on the left ventricle, normal myocardium, and MI region. Two-compartment (K ₁ and k ₂; 2C2P) and three-compartment (K ₁–k ₃; 3C3P) models with irreversible uptake were compared for goodness-of-fit. Partial volume and spillover correction terms (V _a and α = 1 ? V _a ) were also incorporated. LLS and BFM were applied to ROI- and voxel-based kinetic parameter estimations. Results were compared with the standard ROI-based nonlinear least-squares (NLS) results of the corresponding compartment model. A simulation explored statistical properties of the estimation methods.

Results

The 2C2P model was most suitable for describing ¹⁸F-FPTP kinetics. Average K ₁, k ₂, and V _a values were, respectively, 6.8 (ml/min/g), 1.1 (min^?1), and 0.44 in normal myocardium and 1.4 (ml/min/g), 1.1 (min^?1), and 0.32, in MI tissue. Ten minutes of data was sufficient for the estimation. LLS and BFM estimations correlated well with NLS values for the ROI level (K ₁: y = 1.06x + 0.13, r ²  = 0.96 and y = 1.13x + 0.08, r ²  = 0.97) and voxel level (K ₁: y = 1.22x ? 0.30, r ²  = 0.90 and y = 1.26x + 0.00, r ²  = 0.92). Regional distribution of kinetic parametric images (αK ₁, K ₁, k ₂, V _a) was physiologically relevant. LLS and BFM showed more robust characteristics than NLS in the simulation.

Conclusions

Fast kinetics and highly specific uptake of ¹⁸F-FPTP by myocardium enabled quantitative analysis with the 2C2P model using only the initial 10 min of data. LLS and BFM were feasible for estimating voxel-wise parameters. These two methods will be useful for quantitative evaluation of ¹⁸F-FPTP distribution in myocardium and in further studies with different conditions, disease models, and species.

     

Impact of high resolution 3 tesla MR neurography (MRN) on diagnostic thinking and therapeutic patient management

Objective

To evaluate the impact of magnetic resonance neurography (MRN) on diagnostic thinking and therapeutic choices in patients with suspected peripheral neuropathy.

Methods

IRB approval was obtained for this HIPAA-compliant study. Questionnaires were administered to six surgeons regarding the diagnosis and treatment in 85 patients suspected of having peripheral neuropathy, before (pretest) and after (posttest) MRN. Multiple outcome measures related to diagnostic confidence and surgical decision-making were assessed.

Results

The final cohort included 81 patients (30 men and 51 women, age 47?±?17 years). The following changes were observed from pretest to posttest questionnaires: 23 % in nerve involvement (P?<?0.05), 48 % in degree of confidence of nerve involvement (P?<?0.01), 27 % in grade of injury (P?<?0.05), 33 % in differential diagnosis (P?<?0.05), 63 % in degree of confidence in need for surgery (P?<?0.001), 41 % in timing of surgery (P?<?0.01), 30 % in approach to surgery (P?<?0.05), 58 % in degree of confidence in approach to surgery (P?<?0.001), 30 % in estimated length of surgery (P?<?0.05) and 27 % in length of incision (P?<?0.05). The dichotomous decision regarding surgical or nonsurgical treatment changed from pro to con in 17 %.

Conclusion

MRN results significantly influenced the diagnostic thinking and therapeutic recommendations of peripheral nerve surgeons.

Key Points

? In patients with peripheral neuropathy, MRN significantly impacts diagnostic thinking. ? In patients with peripheral neuropathy, MRN significantly impacts therapeutic choices. ? 3-T MRN should be considered in presurgical planning of patients with peripheral neuropathy.

     

Assessment of deep myometrial invasion of endometrial cancer on MRI: added value of second-opinion interpretations by radiologists subspecialized in gynaecologic oncology

Objective

To investigate the added value of secondary reports issued by radiologists subspecializing in gynaecologic imaging for determining deep myometrial invasion of endometrial cancer on MRI.

Methods

Initial (from referring institutions) and secondary (by subspecialized radiologists) interpretations of MRI of 55 patients with endometrial cancer were retrospectively reviewed. A radiologist blinded to clinicopathological information assessed both reports for the presence of deep myometrial invasion. Reference standard was based on hysterectomy specimens. Kappa coefficients (k) were used to measure their concordance. McNemar testing and receiver operating characteristic (ROC) analysis was used to compare sensitivities, specificities and areas under the curves (AUCs).

Results

Deep myometrial invasion was present in 25 (45.5 %) patients. Among 27.3 % (15/55; k?=?0.458) patients with discrepant results, secondary interpretations were correct in 10 (66.7 %) cases. Sensitivity was higher in secondary than in initial reports (76.0 % vs. 48.0 %, p?=?0.039) while no significant difference was seen in specificity (70.0 % vs. 76.7 %, p?=?0.668). At ROC analysis, there was a tendency for higher AUCs in secondary reports (0.785 vs 0.669, p?=?0.096).

Conclusion

Secondary readings of MRI by subspecialized gynaecologic oncologic radiologists may provide incremental value in determining deep myometrial invasion of endometrial cancer.

Key Points

? Deep myometrial invasion is an important prognostic factor in endometrial cancer.? Assessment of deep myometrial invasion is often discrepant between initial and secondary reports.? Secondary reports showed higher sensitivity and accuracy.? Secondary review of MRI may provide incremental value in endometrial cancer patients.

     

The effects of water-based strength exercise on quality of life in young women

Background

Exercise improves quality of life (QoL). However, little is known concerning the effects of different volumes of strength exercise on QoL. The aims of this study are to: (1) evaluate the effects of water-based strength exercise on QoL of healthy young women and (2) compare the effects of different volumes of water-based strength exercises on QoL of healthy young women.

Methods

Sixty-six participants were randomly allocated into four groups with different volumes of exercise. The participants performed water-based strength exercises for 20 weeks, two times a week, supervised by trained physiologists.

Results

A significant improvement was found in overall QoL (F = 5.96; p = 0.018) and in physical (F = 22.01; p < 0.001), psychological (F = 8.408; p = 0.006) and environment domains (F = 8.34; p = 0.006). In addition, a significant decrease of depressive symptoms was found (F = 22.32; p < 0.001). No difference was found between groups in any domain of QoL or depressive symptoms.

Conclusion

Water-based strength exercise improves specific domains of QoL and decreases depressive symptoms of young healthy women. Different volumes of exercise promote similar effects on QoL and depressive symptoms.

     

Exercise training effects on memory and hippocampal viscoelasticity in multiple sclerosis: a novel application of magnetic resonance elastography

Introduction

Cognitive impairment is common and debilitating among persons with multiple sclerosis (MS) and might be managed with exercise training. However, the effects of exercise training on viscoelastic brain properties in this population are unknown. The present pilot study adopted a single-blind randomized controlled trial (RCT) design and is the first to examine the effect of an aerobic exercise training intervention on learning and memory and hippocampal viscoelasticity using magnetic resonance elastography (MRE) in persons with MS.

Methods

Eight fully ambulatory females with MS were randomly assigned into exercise training intervention or waitlist control conditions. The intervention condition involved 12 weeks of supervised, progressive treadmill walking exercise training. All participants underwent measures of learning and memory (i.e., California Verbal Learning Test-II; CVLT-II) and further underwent MRE scans for measurement of shear stiffness (μ) and damping ratio (ξ) of the hippocampus before and after the 12-week period.

Results

Overall, there were small-to-moderate intervention effects on CVLT-II performance (d = 0.34) and large intervention effects on hippocampal μ (d = 0.94) and hippocampal ξ (d = ?1.20). Change in CVLT-II scores was strongly associated with change in μ (r = 0.93, p < 0.01) and ξ (r = ?.96, p < 0.01) of the hippocampus.

Conclusion

This small pilot RCT provides exciting proof-of-concept data supporting progressive treadmill walking exercise training for potentially improving learning and memory and underlying hippocampal viscoelastic properties in persons with MS. This is important given the high prevalence and burden of MS-related memory impairment.

     

Role of curative treatment in patients with intermediate-stage hepatocellular carcinoma

Purpose

To retrospectively evaluate the role of curative treatment in patients with intermediate-stage hepatocellular carcinomas (HCCs), and to identify the subgroup having benefit from curative treatment.

Methods

From April 2000 to December 2014, 100 patients with intermediate-stage HCCs underwent either curative treatment (hepatectomy: n = 23, radiofrequency ablation (RFA); n = 29, both: n = 4) or transarterial chemoembolization (TACE): n = 44) as initial treatments for HCCs. Overall survival, influence of treatment allocation on prognosis, and factors affecting treatment allocation were evaluated.

Results

The 5-year survival rate was 59.2% [95% confidence interval (CI) 51.6–66.8%] in the curative group, and 25.1% (95% CI 11.5–38.7%) in the TACE group. Treatment allocation was the only significant prognostic factor (p = 0.014, hazard ratio: 0.382, 95% CI 0.177–0.821). The curative group consisted of more patients with Child-Pugh A (p = 0.0016) than the TACE group, a tumor number of 3 or fewer (p < 0.0001), a unilobar tumor location (p = 0.02), within 4 of 7 cm criterion (p = 0.001), and within up-to-7 criterion (p = 0.04). Child-Pugh A, within the 4 of 7 cm criterion, and a unilobar tumor location were significantly linked with treatment allocation in multivariate analysis.

Conclusions

Curative treatment can prolong survival in selected patients with intermediate-stage HCCs.

     

Diffusion-weighted MRI for detection of hepatic osteodystrophy in primary sclerosing cholangitis: a comparison study with dual-energy X-ray absorptiometry

Purpose

Osteodystrophy is a frequent complication in primary sclerosing cholangitis (PSC). The aim was to test the feasibility of vertebral bone diffusion-weighted imaging (DWI) in routine liver MRI for detection of osteoporosis using dual-energy X-ray absorptiometry (DXA) as gold standard.

Materials and methods

Forty PSC patients (50 ± 12.6 years) and ten controls (49.5 ± 13.0 years) were scanned using a DWI spin echo echo-planar sequence (b-factors 0–800 s/mm²) on a 3-T MRI system and DXA (76 kVp). The apparent diffusion coefficient (ADC) and T-score were correlated to laboratory and clinical details using Pearson correlation.

Results

In DXA-diagnosed osteoporosis (n = 3) and osteopenia (n = 12), the mean ADC was decreased (0.26 ± 0.03 and 0.30 ± 0.07 × 10^?3 mm²/s) compared to patients with normal DXA scan results (n = 25; 0.32 ± 0.06 × 10^?3 mm²/s). No significant correlation of the ADC and T-score (r = 0.24; p = 0.13) was found, but the T-score correlated significantly to disease duration (r = ?0.33; p = 0.04). In patients with prednisolone therapy (n = 7), the DXA T-score was significantly lower (?1.46 ± 0.49 vs. ?0.16 ± 0.23; p = 0.03).

Conclusion

Diffusion-weighted MRI of the vertebral spine is a feasible technic to detect diffusion alterations caused by osteoporosis but lacks diagnostic capacities for diagnosing minor reductions of the bone mineral density detected by DXA.

     

Evaluation of chronic inflammatory demyelinating polyneuropathy: 3D nerve-sheath signal increased with inked rest-tissue rapid acquisition of relaxation enhancement imaging (3D SHINKEI)

Objective

To evaluate the usefulness of 3D nerve-sheath signal increased with inked rest-tissue rapid acquisition of relaxation enhancement imaging (SHINKEI) in patients with chronic inflammatory demyelinating polyneuropathy (CIDP).

Methods

This institutional review board-approved retrospective study included 14 CIDP patients and nine normal subjects. The signal-to-noise ratio (SNR), contrast ratio (CR), and the size of the cervical ganglions and roots were measured by two raters.

Results

The SNRs of the ganglions and roots were larger in patients with CIDP (9.55?±?3.87 and 9.81?±?3.64) than in normal subjects (7.21?±?2.42 and 5.70?±?2.14, P?<?0.0001, respectively). The CRs of the ganglions and roots were larger in patients with CIDP (0.77?±?0.08 and 0.68?±?0.12) than in normal subjects (0.72?±?0.07 and 0.53?±?0.11, P?<?0.0001, respectively). The sizes of the ganglions and the roots were larger in patients with CIDP (6.44?±?1.61 mm and 4.89?±?1.94 mm) than in normal subjects (5.24?±?1.02 mm and 3.39?±?0.80 mm, P?<?0.0001, respectively).

Conclusions

Patients with CIDP could be distinguished from controls on 3D SHINKEI.

Key points

? 3D SHINKEI could visualize brachial plexus with high spatial resolution.? CIDP patients showed increased SNR, CR, and the size of brachial plexus.? 3D SHINKEI could discriminate CIDP patients from normal subjects.

     

Detection of pulmonary fat embolism with dual-energy CT: an experimental study in rabbits

Objectives

To evaluate the use of dual-energy CT imaging of the lung perfused blood volume (PBV) for the detection of pulmonary fat embolism (PFE).

Methods

Dual-energy CT was performed in 24 rabbits before and 1 hour, 1 day, 4 days and 7 days after artificial induction of PFE via the right ear vein. CT pulmonary angiography (CTPA) and lung PBV images were evaluated by two radiologists, who recorded the presence, number, and location of PFE on a per-lobe basis. Sensitivity, specificity, and accuracy of CTPA and lung PBV for detecting PFE were calculated using histopathological evaluation as the reference standard.

Results

A total of 144 lung lobes in 24 rabbits were evaluated and 70 fat emboli were detected on histopathological analysis. The overall sensitivity, specificity and accuracy were 25.4 %, 98.6 %, and 62.5 % for CTPA, and 82.6 %, 76.0 %, and 79.2 % for lung PBV. Higher sensitivity (p?<?0.001) and accuracy (p?<?0.01), but lower specificity (p?<?0.001), were found for lung PBV compared with CTPA. Dual-energy CT can detect PFE earlier than CTPA (all p?<?0.01).

Conclusion

Dual-energy CT provided higher sensitivity and accuracy in the detection of PFE as well as earlier detection compared with conventional CTPA in this animal model study.

Key points

? Fat embolism occurs commonly in patients with traumatic bone injury.? Dual-energy CT improves diagnostic performance for pulmonary fat embolism detection.? Dual-energy CT can detect pulmonary fat embolism earlier than CTPA.