Diagnostic accuracy of biopsy after neoadjuvant treatment for well-differentiated and dedifferentiated retroperitoneal liposarcoma

PURPOSE

Accurate histopathological grading of percutaneous biopsies is essential to guide adequate management of patients with suspected retroperitoneal liposarcoma. In this regard, however, limited reliability has been described. Therefore, we conducted a retrospective study to assess the diagnostic accuracy in retroperitoneal soft tissue sarcomas and simultaneously investigate its impact on patients' survival.

MATERIALS AND METHODS

Reports of an interdisciplinary sarcoma tumor board between 2012 and 2022 were systematically screened for patients with well-differentiated (WDLPS) and dedifferentiated retroperitoneal liposarcoma (DDLPS). Histopathological grading on pre-operative biopsy was correlated with corresponding postoperative histology. Additionally, patients' survival outcomes were examined. All analyses were performed in two subgroups: patients with primary surgery and patients with neoadjuvant treatment.

RESULTS

A total of 82 patients met our inclusion criteria. Diagnostic accuracy of patients who underwent upfront resection (n = 32) was significantly inferior to patients with neoadjuvant treatment (n = 50) (66% versus 97% for WDLPS, p < 0.001; 59% versus 97% for DDLPS, p < 0.001). For patients with primary surgery, histopathological grading on biopsy and surgery was concordant in only 47% of cases. Sensitivity for detecting WDLPS was higher than for DDLPS (70% versus 41%). Higher histopathological grading in surgical specimens correlated with worse survival outcomes (p = 0.01).

CONCLUSION

Histopathological grading of RPS may no longer be reliable after neoadjuvant treatment. The true accuracy of the percutaneous biopsy may need to be studied in patients who do not receive neoadjuvant treatment. Future biopsy strategies should aim to improve identification of DDLPS to inform patient management.

Impact of Dynamic Contrast Enhanced and Diffusion-Weighted MR Imaging on Detection of Early Local Recurrence of Soft Tissue Sarcoma

BACKGROUND

Diagnosis of residual or recurrent tumor in soft-tissue sarcomas (STS) is a differential diagnostic challenge since post-therapeutic changes impede diagnosis.

PURPOSE

To evaluate the diagnostic accuracy of quantitative dynamic contrast enhanced (DCE)-MRI and diffusion-weighted imaging (DWI) to detect local recurrence of STS of the limb.

STUDY TYPE

Prospective.

POPULATION

A totalof 64 consecutive patients with primary STS of the limbs were prospectively included 3-6 months after surgery between January 2016 and July 2021.

FIELD STRENGTH/SEQUENCE

A 1.5 T; axial DWI echo-planar imaging sequences and DCE-MRI using a 3D T1-weighted spoiled gradient-echo sequence.

ASSESSMENT

The quantitative DCE-MRI parameters relative plasma flow (rPF) and relative mean transit time (rMTT) were calculated and ADC mapping was used to quantify diffusion restriction. Regions of interest of tumor growth and postoperative changes were drawn in consensus by two experts for diffusion and perfusion analysis. An additional morphological assessment was done by three independent and blinded radiologists.

STATISTICAL TEST

Unpaired t-test, ROC-analysis, and a logistic regression model were applied. Interobserver reliability was calculated using Fleiss kappa statistics. A P value of 0.05 was considered statistically significant.

RESULTS

A total of 11 patients turned out to have local recurrence. rPF was significantly higher in cases of local recurrence when compared to cases without local recurrence (61.1-4.5) while rMTT was slightly and significantly lower in local recurrence. ROC-analysis showed an area under the curve (AUC) of 0.95 (SEM ± 0.05) for rPF while a three-factor multivariate logistic regression model showed a high diagnostic accuracy of rPF (R²  = 0.71). Compared with morphological assessment, rPF had a distinct higher specificity and true positive value in detection of LR.

DATA CONCLUSION

DCE-MRI is a promising additional method to differentiate local recurrence from benign postoperative changes in STS of the limb. Especially specificity in detection of LR is increased compared to morphological assessment.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY: Stage 2.

Optimized visualization of focal liver lesions and vascular structures in real-time T1-weighted gradient echo sequences for magnetic resonance-guided liver procedures

PURPOSE

This study aimed to determine the optimal sequence parameters of a real-time T1-weighted (T1w) gradient echo (GRE) sequence for magnetic resonance (MR)-guided liver interventions.

METHODS

We included 94 patients who underwent diagnostic liver MR imaging (MRI) and acquired additional real-time T1w GRE sequences with a closed 1.5-T MRI scanner 20 min after a liver-specific contrast agent was injected. In four measurement series, one of the following four sequence parameters was changed, and repeated scans with different values for this parameter were acquired: flip angle (FA) (10-90°), repetition time (TR) (5.47-8.58 ms), bandwidth (BW) (300-700 Hz/pixel), and matrix (96 × 96-256 × 256). Two readers rated the visualizations of the target and risk structures (7-point Likert scale) and the extent of artifacts (6-point Likert scale); they also quantified the lesion-liver contrast ratio, the lesion-liver contrast-to-noise ratio (CNR), and the liver signal-to-noise ratio (SNR). Substratification analyses were performed for differences in overall visual and quantitative assessments depending on the lesion size, type, and the presence of cirrhosis.

RESULTS

For the utilized FAs and matrix sizes, significant differences were found in the visual assessments of the conspicuity of target lesions, risk structures, and the extent of artifacts as well as in the quantitative assessments of lesion-liver contrast ratios and liver SNRs (all P < 0.001). No differences were observed for modified TR and BW. Significantly increased conspicuity of the target and vascular structures was observed for both higher FAs and matrix sizes, while the ghosting artifacts increased and decreased, respectively. For primary liver tumors compared with metastatic lesions, and for cirrhotic livers compared with normal liver parenchyma, significantly decreased conspicuity of the target lesions (P = 0.005, P = 0.005), lesion-liver CNRs (P = 0.005, P = 0.032), and lesion-liver contrast ratios (P = 0.015, P = 0.032) were found. All results showed no significant correlation with lesion size.

CONCLUSION

We recommend an FA of 30°-45° and a matrix size of 128 × 128-192 × 192 for MR-guided liver interventions with real-time T1w sequences to provide a balance between good visualizations of target and risk structures, high signal intensities, and low ghosting artifacts. The visualization of the target lesion may vary due to clinical conditions, such as lesion type or associated chronic liver disease.

[Postoperative imaging of the hip]

CLINICAL ISSUE

To assess postoperative imaging of the hip joint regarding possible complications, it is indispensable to have in-depth knowledge of commonly used surgical techniques, access routes, and the implanted materials.

STANDARD RADIOLOGICAL METHODS

While radiography is used to evaluate the position of foreign material and to rule out periprosthetic fractures that have occurred intraoperatively, follow-up examinations might show signs of material failure, aseptic loosening, prosthesis infections, or the occurrence of heterotopic ossifications. If radiographic findings are ambiguous, computed tomography (CT) may be used to clarify findings, whereas magnetic resonance imaging (MRI) is helpful to identify intra- and periarticular soft tissue pathologies such as surgery-associated cartilage and ligament damage, muscle insufficiency, or metallosis.

METHODOLOGICAL INNOVATION AND EVALUATION

To guide clinical decision making in common postoperative complications, various classification systems are available, e.g., for periprosthetic fractures, aseptic loosening, or heterotopic ossification. However, the differentiation between aseptic material loosening and septic endoprosthesis infection remains challenging if based on imaging alone.

PRACTICAL RECOMMENDATIONS

The assessment of postoperative hip imaging should be closely linked to the respective surgical technique and the implanted foreign material, whereby different probabilities of specific complications can be derived.

Incidental CT Findings in the Elderly with Low-Energy Falls: Prevalence and Implications

Background: Computed tomography (CT) is commonly used in trauma care, with increasing implementation during the emergency work-up of elderly patients with low-energy falls (LEF). The prevalence of incidental findings (IFs) resulting from CT imaging and requiring down-stream actions in this patient cohort is unknown. We have investigated the prevalence and urgency of IFs from emergency CT examinations in these patients. Methods: A total of 2871 patients with LEF and emergency CT examinations were consecutively included in this retrospective cohort study. The primary endpoint was the prevalence of IFs; the secondary endpoint was their urgency. Results: The median age was 82 years (64.2% were women). IFs were identified in 73.9% of patients, with an average of 1.6 IFs per patient. Of all IFs, 16.4% were classified as urgent or relevant, predominantly in the abdomen, chest and neck. Increasing age was associated with the prevalence of an IF (odds ratio: 1.053, 95% confidence interval: 1.042–1.064). Significantly more IFs were found in female patients (75.2% vs. 71.5%). Conclusion: IFs resulting from CT examinations of the elderly are frequent, but in more than 8 out of 10, they are harmless or currently asymptomatic. For the benefit of an accurate diagnosis of traumatic lesions, concerns about IFs with respect to disease burden, further work-up and resource utilisation might be disregarded.

Artifact reduction of coaxial needles in magnetic resonance imaging-guided abdominal interventions at 1.5 T: a phantom study

Needle artifacts pose a major limitation for MRI-guided interventions, as they impact the visually perceived needle size and needle-to-target-distance. The objective of this agar liver phantom study was to establish an experimental basis to understand and reduce needle artifact formation during MRI-guided abdominal interventions. Using a vendor-specific prototype fluoroscopic T1-weighted gradient echo sequence with real-time multiplanar acquisition at 1.5 T, the influence of 6 parameters (flip angle, bandwidth, matrix, slice thickness, read-out direction, intervention angle relative to B₀) on artifact formation of 4 different coaxial MR-compatible coaxial needles (Nitinol, 16G–22G) was investigated. As one parameter was modified, the others remained constant. For each individual parameter variation, 2 independent and blinded readers rated artifact diameters at 2 predefined positions (15 mm distance from the perceived needle tip and at 50% of the needle length). Differences between the experimental subgroups were assessed by Bonferroni-corrected non-parametric tests. Correlations between continuous variables were expressed by the Bravais–Pearson coefficient and interrater reliability was quantified using the intraclass classification coefficient. Needle artifact size increased gradually with increasing flip angles (p = 0.002) as well as increasing intervention angles (p < 0.001). Artifact diameters differed significantly between the chosen matrix sizes (p = 0.002) while modifying bandwidth, readout direction, and slice thickness showed no significant differences. Interrater reliability was high (intraclass correlation coefficient 0.776–0.910). To minimize needle artifacts in MRI-guided abdominal interventions while maintaining optimal visibility of the coaxial needle, we suggest medium-range flip angles and low intervention angles relative to B₀.

Measuring HCC Tumor Size in MRI-The Sequence Matters!

BACKGROUND

The aim of this paper was to assess and compare the accuracy of common magnetic resonance imaging (MRI) pulse sequences in measuring the lesion sizes of hepatocellular carcinomas (HCCs) with respect to the Milan criteria and histopathology as a standard of reference.

METHODS

We included 45 patients with known HCC who underwent contrast-enhanced MRI of the liver prior to liver transplantation or tumor resection. Tumor size was assessed pathologically for all patients. The MRI protocol contained axial T2-weighted images as well as T1-weighted imaging sequences before and after application of Gd-EOB-DTPA. Tumor diameters, the sharpness of lesions, and the presence of artifacts were evaluated visually on all available MRI sequences. MRI measurements and pathologically assessed tumor dimensions were correlated using Pearson's correlation coefficient and Bland-Altman plots. The rate of misclassifications following Milan criteria was assessed.

RESULTS

The mean absolute error (in cm) of MRI size measurements in comparison to pathology was the smallest for the hepatobiliary phase T1-weighted acquisition (0.71 ± 0.70 cm, r = 0.96) and largest for the T2w turbo-spin-echo (TSE) sequence (0.85 ± 0.78 cm, r = 0.94). The misclassification rate regarding tumor size under the Milan criteria was lowest for the T2w half-Fourier acquisition single-shot turbo spin-echo sequence and the hepatobiliary phase T1w acquisition (each 8.6%). The highest rate of misclassification occurred in the portal venous phase T1w acquisition and T2w TSE sequence (each 14.3%).

CONCLUSIONS

The hepatobiliary phase T1-weighted acquisition seems to be most accurate among commonly used MRI sequences for measuring HCC tumor size, resulting in low rates of misclassification with respect to the Milan criteria.

[Interventional radiology as emergency treatment for pelvic injuries]

CLINICAL ISSUE

Pelvic arterial bleeding constitutes a potentially life-threatening event, which can be difficult to control with surgical procedures alone, especially in the case of ligamentous ruptures and a subsequently increased pelvic volume.

STANDARD RADIOLOGICAL PROCEDURES

Using angiography and embolization (AE) with resorbable gelatine-based particles or permanent coils, plugs, liquid embolic systems or by vascular stenting, in most cases traumatic pelvic arterial bleeding can be stopped and can also be used to close pseudoaneurysms, arteriovenous fistulas or dissections.

METHODOLOGICAL INNOVATION AND EVALUATION

The AE has become established as a fast and effective minimally invasive procedure in the treatment of traumatic pelvic vascular injuries with an advantageous risk-benefit ratio.

PRACTICAL RECOMMENDATIONS

An interdisciplinary approach should be used in the indications for AE; which can be used as definitive treatment as well as in combination with surgical procedures. To improve the clinical outcome any delay between establishing the indications and the start of the intervention must be avoided.

Quantitative Analysis of the Time-Intensity Curve of Contrast-Enhanced Ultrasound of the Liver: Differentiation of Benign and Malignant Liver Lesions

Background: To evaluate the diagnostic accuracy of quantitative perfusion parameters in contrast-enhanced ultrasound to differentiate malignant from benign liver lesions. Methods: In this retrospective study 134 patients with a total of 139 focal liver lesions were included who underwent contrast enhanced ultrasound (CEUS) between 2008 and 2018. All examinations were performed by a single radiologist with more than 15 years of experience using a second-generation blood pool contrast agent. The standard of reference was histopathology (n = 60), MRI or CT (n = 75) or long-term CEUS follow up (n = 4). For post processing regions of interests were drawn both inside of target lesions and the liver background. Time–intensity curves were fitted to the CEUS DICOM dataset and the rise time (RT) of contrast enhancement until peak enhancement, and a late-phase ratio (LPR) of signal intensities within the lesion and the background tissue, were calculated and compared between malignant and benign liver lesion using Student’s t-test. Quantitative parameters were evaluated with respect to their diagnostic accuracy using receiver operator characteristic curves. Both features were then combined in a logistic regression model and the cumulated accuracy was assessed. Results: RT of benign lesions (14.8 ± 13.8 s, p = 0.005), and in a subgroup analysis, particular hemangiomas (23.4 ± 16.2 s, p < 0.001) differed significantly to malignant lesions (9.3 ± 3.8 s). The LPR was significantly different between benign (1.59 ± 1.59, p < 0.001) and malignant lesions (0.38 ± 0.23). Logistic regression analysis with RT and LPR combined showed a high diagnostic accuracy of quantitative CEUS parameters with areas under the curve of 0.923 (benign vs. malignant) and 0.929 (hemangioma vs. malignant. Conclusions: Quantified CEUS parameters are helpful to differentiate malignant from benign liver lesions, in particular in case of atypical hemangiomas.

[The (severely) injured pregnant patient from the perspective of radiology]

Trauma is one of the leading causes of mortality in pregnant women and significantly increases the likelihood of an unwanted termination of pregnancy. Particularly in severe trauma with an increased risk of significant maternal injuries, computed tomography (CT) remains the imaging modality of choice as it is comprehensively available, quick to carry out and has a high diagnostic accuracy in the detection and classification of life-threatening trauma-associated pathologies compared to other imaging techniques. Considering the radiation-associated risks, it is unlikely that a single, monophasic CT in the emergency trauma room will exceed the threshold of deterministic radiation damage; therefore, fetal malformations or fetal loss are not to be expected; however, there is a low stochastic risk for the delayed occurrence of radiation-induced cancer both for the child and the mother that can be considered small in comparison to missed or delayed diagnoses after severe trauma. Intravenous, nonionic iodinated contrast agents are not contraindicated during pregnancy and should be administered whenever their use would also be considered appropriate in a nonpregnant patient; however, unnecessary scans and, if possible, multiple contrast agent phases should be avoided in order to reduce radiation. Magnetic resonance imaging (MRI) has a major role in the subacute setting and constitutes an excellent problem solver for specific questions, such as the evaluation of discoligamentous injuries of the spine. Its use is deemed acceptable at any stage of pregnancy when the required information is considered important for the management of further treatment. Due to potential teratogenic effects of MRI contrast media containing gadolinium on the fetus, including an increased likelihood of fetal loss, they should only be administered with great caution and under strictly defined indications.

[Resuscitation room diagnostics]

CLINICAL PROBLEM

The indication for resuscitation room care is an acute (potentially) life-threatening patient condition. Typical causes for this are polytrauma, acute neurological symptoms, acute chest and abdominal pain or the cause remains unclear at first. The care is always provided in a suitably composed interdisciplinary team. This requires cause-specific standards tailored to the care facility and requires a mutual understanding of the partners involved with regard to specialist interests and care processes.

STANDARD RADIOLOGICAL METHODS

Whole-body CT is established for polytrauma imaging and usually each institution has already defined an institutional standard. For the other causes, first imaging with CT is just as common, but the protocols and procedures to be used are often not as clear as in the case of polytrauma.

METHODICAL INNOVATION AND EVALUATION

For polytrauma service, ATLS and procedures according to ABCDE already serve as a largely standardized framework in the resuscitation room. For every other group of causes, comparable concepts should be developed and institutionally strive for objectification of continuous improvement. This refers not only to the resuscitation room stay but also to the interfaces before and after resuscitation room service.

PRACTICAL RECOMMENDATIONS

After the patient has arrived, it has to be determined whether the assessment of a vital risk is retained. If so, institutionally defined care standards must be followed for the various causes. This concerns the interface logistics, the definition of a team leader including associated tasks, the supply processes including the CT examination protocols as well as the close communication.

[Interventional radiology as emergency therapy]

CLINICAL ISSUE

Both the progress of surgical techniques and the demographic development with increasing numbers of multimorbid patients demand and also encourage radiology in the setting of trauma and acute emergencies. In addition to a fast and precise diagnostics, this also includes image-guided, minimally invasive therapy to control and treat several acute pathologies.

STANDARD RADIOLOGICAL PROCEDURES

Computed tomography (CT) is not only important for the diagnosis of abscesses, active bleeding or other acute pathologies, but also allows minimally invasive therapy. While digital subtraction angiography (DSA) guides catheter-based procedures, e.g., to control bleedings or to place percutaneous transhepatic cholangiodrain (PTCD), fluoroscopy allows the 3D-visualization to drain abdominal and thoracic abscesses.

METHODOLOGICAL INNOVATION AND EVALUATION

Radiology has established itself in the treatment of acute emergencies or acute complications through gentle and usually fast minimally invasive procedures. Presumably, MRI interventions will become increasingly important in the near future and, thus, complement the portfolio.

PRACTICAL RECOMMENDATIONS

Every clinical radiologist who works on night shifts should be able to safely carry out some basic interventional techniques in order to stabilize the patient and at least ensure medically safe bridging to the next routine workday. Due to the diversity of materials and the rarity and difficulty of some procedures, the full portfolio requires years of expertise and will therefore remain restricted to specialized interventional radiologists.

Contrast-enhanced ultrasound (CEUS) and gallbladder diseases - A retrospective mono-center analysis of imaging findings with histopathological correlation

BACKGROUND

Radiologic imaging, especially ultrasound has an important role in the assessment of gallbladder alteration. Contrast-enhanced ultrasound (CEUS) is an easy and fast imaging technique that overcomes the limitations of greyscale ultrasonography. It is a safe tool that can be used as an additional imaging modality in order to elucidate and differentiate gallbladder pathological findings.

OBJECTIVE

The aim of this retrospective study analysis is to assess the diagnostic performance of CEUS in gallbladder alterations and compare the results to the histopathological findings.

METHODS

A total of 17 patients between 2009 and 2017 with uncertain gallbladder appearance were retrospectively analysed. A single experienced physician with more than fifteen years' experience performed CEUS examinations by applying a second-generation blood pool agent (SonoVue®, Bracco, Milan, Italy). Archived images were interpreted by the same physician and compared to the histopathological findings.

RESULTS

CEUS results, when correlated to the respectively pathologic findings, presented a sensitivity of 100%, a specificity of 100%, a positive predictive value (PPV) of 100% and a negative predictive value (NPV) of 100%. All patients were successfully examined without any adverse reaction.

CONCLUSION

In conclusion, the excellent results in this study acknowledged that CEUS is a feasible alternative tool to differentiate gallbladder pathologic alterations.

Comparison of PIRADS 3 lesions with histopathological findings after MRI-fusion targeted biopsy of the prostate in a real world-setting

INTRODUCTION

We aimed to evaluate whether PIRADS 3 lesions in multiparametric MRI (mpMRI) represent a significant risk of prostate cancer (PCa) in a real-world setting of different referring radiologic institutes.

MATERIALS AND METHODS

Between May 2015 and October 2017, a total of 408 patients were referred to our clinic for MRI-ultrasound fusion targeted biopsy of the prostate (FusPbx) due to suspected prostate cancer. In all patients, preoperatively an mpMRI of the prostate was performed by altogether 62 different radiologic institutes. Prostate lesions were classified according to the PIRADS system. A PIRADS 3 lesion was diagnosed in 41 patients. FusPbx was performed transrectally using a Philips EPIQ 7 (Philips Medical Systems, Bothell, WA) scanner with plane wise fusion of ultrasound and MRI image data. In addition to FusPbx in each patient a randomized 12-core transrectal ultrasound guided biopsy (USPbx) was performed.

RESULTS

Mean PSA Level was 9.5 ng/ml (range: 1- 26 ng/ml), mean patients age was 66.1 years (48.6- 80.4). In 11/41 patients (26.8%) prostate cancer was diagnosed by FusPbx of the PIRADS 3 lesion. In the target lesion PCa was classified as Gleason Score 3+3 in 5 patients, as 3+4 in 3, 4+3 in 1, 4+4 in 1 and 4+5 in 1 patient. In patients with negative FusPbx USPbx revealed PCa in another 7 patients (17.1%). In 5 of these GS 3+3 PCa was found, in another 2 patients GS 3+4 PCa.

CONCLUSIONS

PIRADS 3 lesion indicates an equivocal likelihood of significant prostate cancer. In our series the overall PCa detection rate was 26.8% and 14.6% for clinically significant cancer in PIRADS 3 lesions. This evokes the question, if PIRADS 3 lesions could be surveilled only. The findings should be confirmed in a larger series.

Metabolite profiles evaluated, according to sex, do not predict resting energy expenditure and lean body mass in healthy non-obese subjects

PURPOSE

Differences in resting energy expenditure (REE) between men and women mainly result from sex-related differences in lean body mass (LBM). So far, a little is known about whether REE and LBM are reflected by a distinct human metabolite profile. Therefore, we aimed to identify plasma and urine metabolite patterns that are associated with REE and LBM of healthy subjects.

METHODS

We investigated 301 healthy male and female subjects (18-80 years) under standardized conditions in the cross-sectional KarMeN (Karlsruhe Metabolomics and Nutrition) study. REE was determined by indirect calorimetry and LBM by dual X-ray absorptiometry. Fasting blood and 24 h urine samples were analyzed by targeted and non-targeted metabolomics methods using GC × GC-MS, GC-MS, LC-MS, and NMR. Data were evaluated by predictive modeling of combined data using different machine learning algorithms, namely SVM, glmnet, and PLS.

RESULTS

When evaluating data of men and women combined, we were able to predict REE and LBM with high accuracy (> 90%). This, however, was a clear effect of sex, which is supported by the high degree of overlap in identified important metabolites for LBM, REE, and sex, respectively. The applied machine learning algorithms did not reveal a metabolite pattern predictive of REE or LBM, when analyzing data for men and women, separately.

CONCLUSIONS

We could not identify a sex independent predictive metabolite pattern for REE or LBM. REE and LBM have no impact on plasma and urine metabolite profiles in the KarMeN Study participants. Studies applying metabolomics in healthy humans need to consider sex specific data evaluation.

Improved detection of a tumorous involvement of the mesorectal fascia and locoregional lymph nodes in locally advanced rectal cancer using DCE-MRI

PURPOSE

The prediction of an infiltration of the mesorectal fascia (MRF) and malignant lymph nodes is essential for treatment planning and prognosis of patients with rectal cancer. The aim of this study was to assess the additional diagnostic value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for the detection of a malignant involvement of the MRF and of mesorectal lymph nodes in patients with locally advanced rectal cancer.

METHODS

In this prospective study, 22 patients with locally advanced rectal cancer were examined with 1.5-T MRI between September 2012 and April 2015. Histopathological assessment of tumor size, tumor infiltration to the MRF, and malignant involvement of locoregional lymph nodes served as standard of reference. Sensitivity and specificity of detecting MRF infiltration and malignant nodes (nodal cut-off size [NCO] ≥ 5 and ≥ 10 mm, respectively) was determined by conventional MRI (cMRI; precontrast and postcontrast T1-weighted, T2-weighted, and diffusion-weighted images) and by additional semi-quantitative DCE-MRI maps (cMRI+DCE-MRI).

RESULTS

Compared to cMRI, additional semi-quantitative DCE-MRI maps significantly increased sensitivity (86 vs. 71% [NCO ≥ 5 mm]/29% [NCO ≥ 10 mm]) and specificity (90 vs. 70% [NCO ≥ 5 mm]) of detecting malignant lymph nodes (p < 0.05). Moreover, DCE-MRI significantly augmented specificity (91 vs. 82%) of discovering a MRF infiltration (p < 0.05), while there was no change in sensitivity (83%; p > 0.05).

CONCLUSION

DCE-MRI considerably increases both sensitivity and specificity for the detection of small mesorectal lymph node metastases (≥ 5 mm but < 10 mm) and sufficiently improves specificity of a suspected MRF infiltration in patients with locally advanced rectal cancer.

Contrast-Enhanced Ultrasound in the Follow-Up of Endoleaks after Endovascular Aortic Repair (EVAR)

Endovascular aortic repair (EVAR) has become established in the treatment of abdominal aortic aneurysms and shows potential benefits such as a low perioperative morbidity and a short hospitalization duration. The follow-up after EVAR primarily consists of lifelong postinterventional imaging of the aneurysm size in order to detect complications such as endoleaks or stent dislocation. Computed tomography angiography, an imaging modality that uses ionizing radiation and that relies on a contrast medium which is dependent on thyroid and renal function, is widely used for follow-up. Meanwhile, contrast-enhanced ultrasound (CEUS) has been established as a viable, fast and cost-effective imaging alternative for the follow-up and the detection of endoleaks after EVAR with the additional benefit of being a real-time non-ionizing radiation examination and having comparable or even superior diagnostic performance. This review describes the use of CEUS for follow-up after EVAR and describes the most common pathologies.

Structured reporting of MRI of the shoulder - improvement of report quality?

OBJECTIVES

To evaluate the effect of structured reports (SRs) in comparison to non-structured narrative free text (NRs) shoulder MRI reports and potential effects of both types of reporting on completeness, readability, linguistic quality and referring surgeons' satisfaction.

METHODS

Thirty patients after trauma or with suspected degenerative changes of the shoulder were included in this study (2012-2015). All patients underwent shoulder MRI for further assessment and possible surgical planning. NRs were generated during clinical routine. Corresponding SRs were created using a dedicated template. All 60 reports were evaluated by two experienced orthopaedic shoulder surgeons using a questionnaire that included eight questions.

RESULTS

Eighty per cent of the SRs were fully complete without any missing key features whereas only 45% of the NRs were fully complete (p < 0.001). The extraction of information was regarded to be easy in 92% of the SRs and 63% of the NRs. The overall quality of the SRs was rated better than that of the NRs (p < 0.001).

CONCLUSIONS

Structured reporting of shoulder MRI improves the readability as well as the linguistic quality of radiological reports, and potentially leads to a higher satisfaction of referring physicians.

KEY POINTS

• Structured MRI reports of the shoulder improve readability. • Structured reporting facilitates information extraction. • Referring physicians prefer structured reports to narrative free text reports. • Structured MRI reports of the shoulder can reduce radiologist re-consultations.

Vertebral artery hypoplasia: frequency and effect on cerebellar blood flow characteristics

BACKGROUND AND PURPOSE

Vertebral artery hypoplasia (VAH) is supposed to be a risk factor for posterior circulation ischemia (PCI), particularly in the territory of the posterior inferior cerebellar artery (PICA). The aim of our study was to determine whether VAH impedes perfusion in the dependent PICA territory even in the absence of manifest PCI.

METHODS

VA diameter was retrospectively measured in 934 consecutive patients who underwent whole-brain multimodal computed tomography because of suspected stroke. VAH was defined by a diameter of ≤2 mm and an asymmetry ratio of ≤1:1.7 of both VAs. We performed blinded computed tomography perfusion reading in patients with VAH without PCI (MRI-confirmed) and in control patients (ratio 1:2) with normal VAs. Four different perfusion maps were evaluated for a relative hypoperfusion in the PICA territory.

RESULTS

VAH was found in 146 of 934 patients (15.6%). It was more frequent on the right side (66.1%). Of 146 patients, 59 without PCI qualified for computed tomography perfusion analysis. Depending on the perfusion map, ≤42.4% (25/59) of patients with VAH, but only 7.6% (9/118) without VAH, showed an ipsilateral PICA hypoperfusion (P<0.001). Sensitivities in patients with VAH were as follows: time to drain 42.4% (25/59)>mean transit time 39.0% (23/59)>cerebral blood flow 25.4% (15/59). Cerebral blood volume was never affected.

CONCLUSIONS

VAH is a frequent vascular variant that can lead to a relative regional hypoperfusion in the PICA territory. Additional research should clarify the pathophysiological role of VAH in PCI.

Diagnostic accuracy of dynamic gadoxetic-acid-enhanced MRI and PET/CT compared in patients with liver metastases from neuroendocrine neoplasms

PURPOSE

To evaluate the diagnostic accuracy of dynamic-contrast-enhanced (DCE) MRI in comparison to both (18)F-FDG- and (68)Ga-DOTATATE-PET/CT in patients with liver metastases of neuroendocrine neoplasms (NEN).

MATERIALS AND METHODS

Thirty-two patients with hepatic metastases from NEN were examined both in DCE-MRI and positron emission tomography/computed tomography (PET/CT), using either (18)F-fluorodeoxyglucose ((18)F-FDG) or (68)Ga-DOTATATE as tracer. DCE-MRI was performed at 3 Tesla with Gd-EOB-DTPA acquiring 48 slices every 2.2 s for 5 min. Three regions of interest (ROIs) representing liver background and liver metastases were defined in fat-saturated T1w three-dimensional GRE MRI sequences in the hepatobiliary phase. Corresponding ROIs were then defined in the DCE-MRI- and in the PET/CT-dataset. Area under the curve (AUC) was calculated for the differentiation between metastases and liver background for DCE-MRI and PET-CT parameters.

RESULTS

AUC was very high for SUVmean (mean standardized uptake value) derived from (68)Ga-DOTATATE- (AUC = 0.966), and (18)F-FDG-PET/CT (AUC = 0.989). For DCE-MRI parameters, arterial flow fraction and intracellular uptake fraction showed the highest AUCs (AUC = 0.826, AUC = 0.819, respectively). The combination of those two had an AUC of 0.949. The combination of DCE-MRI and PET-CT parameters resulted in the highest AUC.

CONCLUSION

Both PET/CT parameters and DCE-MRI perfusion parameters show a high diagnostic accuracy in the distinction between liver metastases and liver tissue. Our data suggest that both modalities provide complementary information.

Automated quantification of pulmonary perfused blood volume by dual-energy CTPA in chronic thromboembolic pulmonary hypertension

OBJECTIVES

The aim of the study was to determine whether automated quantification of pulmonary perfused blood volume (PBV) in dual-energy computed tomography pulmonary angiography (DE-CTPA) can be used to assess the severity of chronic thromboembolic pulmonary hypertension (CTEPH).

METHODS

Automated quantification of PBV was performed in 25 consecutive CTEPH patients undergoing DE-CTPA. PBV values were correlated with cardiac index and pulmonary vascular resistance quantified by right heart catheterization and walking distance in the 6-minute walk test using Pearson's correlation coefficient and multivariate linear regression analysis to control for age and gender.

RESULTS

DE-CTPA derived PBV values inversely correlated with systolic (r = -0.64, p = 0.001) and mean (r = -0.57, p = 0.004) pulmonary arterial pressure. There was a trend for PBV values to inversely correlate with pulmonary vascular resistance (r = -0.20, p = 0.35). No significant correlation was found between PBV values and cardiac index or 6-minute walking distance. These correlations were confirmed to be independent of age and gender on multivariate linear regression analysis.

CONCLUSION

DE-CTPA can be used for an automated quantification of pulmonary PBV in chronic thromboembolic pulmonary hypertension. PBV values correlate inversely with systolic and mean pulmonary arterial pressure and can thus be used to estimate the severity of pulmonary hypertension in these patients. Citation Format: • Meinel FG, Graef A, Thierfelder KM et al. Automated Quantification of Pulmonary Perfused Blood Volume by Dual-Energy CTPA in Chronic Thromboembolic Pulmonary Hypertension. Fortschr Röntgenstr 2014; 186: 151 - 156.

Soybean oil: a potentially new intravascular perfusate

BACKGROUND

Given that micelles of lipids are colloids, the hypothesis was generated that the rapid administration of large volumes of soybean oil micelles would be an effective perfusion fluid. We also hypothesized that oxygen loading would be enhanced due to the greater solubility of oxygen in lipids compared to water.

METHODS

A 100% lethal mouse model of blood loss was used to compare the ability of soybean oil micelles to that of Ringer's lactate, blood and other fluids, with respect to raising and maintaining the blood pressure for one hour. Oxygen on- and off-loading of various concentrations of soybean oil micelles was determined using mass spectroscopy. Nitric oxide uptake by micelles was also determined in a similar fashion.

RESULTS

A 20% soybean oil emulsion was superior to Ringer's lactate in raising and maintaining blood pressure. A 20% soybean oil emulsion with 5% albumin added was superior to shed blood as well as solutions comprised of 5% albumin added to either normal saline or Ringer's lactate. There was a linear relationship between oxygen content and micelle concentration between 10% and 30%. Off-loading of oxygen from the micelles was nearly as fast as off-loading from water. Nitric oxide also loaded preferentially onto soybean oil micelles.

CONCLUSIONS

(1) Soybean oil emulsions were superior to other fluids in restoring and maintaining the blood pressure; (2) oxygen-carrying ability of soybean oil micelles exceeds that of water and follows Henry's law between 10% and 30% w/v oil content; (3) nitric oxide was carried by the micelles; (4) animals receiving soybean oil micelles did not exhibit fat embolization; (5) colloids comprised of soybean oil-containing micelles may be used to replace blood loss and may be used to deliver oxygen and other potentially therapeutic gases such as nitric oxide to tissues.

An evaluation of selenium concentrations in water, sediment, invertebrates, and fish from the Republican River Basin: 1997-1999

The Republican River Basin of Colorado, Nebraska, and Kansas lies in a valley which contains Pierre Shale as part of its geological substrata. Selenium is an indigenous constituent in the shale and is readily leached into surrounding groundwater. The Basin is heavily irrigated through the pumping of groundwater, some of which is selenium-contaminated, onto fields in agricultural production. Water, sediment, benthic invertebrates, and/or fish were collected from 46 sites in the Basin and were analyzed for selenium to determine the potential for food-chain bioaccumulation, dietary toxicity, and reproductive effects of selenium in biota. Resulting selenium concentrations were compared to published guidelines or biological effects thresholds. Water from 38% of the sites (n = 18) contained selenium concentrations exceeding 5 microg L(-1), which is reported to be a high hazard for selenium accumulation into the planktonic food chain. An additional 12 sites (26% of the sites) contained selenium in water between 3-5 microg L(-1), constituting a moderate hazard. Selenium concentrations in sediment indicated little to no hazard for selenium accumulation from sediments into the benthic food chain. Ninety-five percent of benthic invertebrates collected exhibited selenium concentrations exceeding 3 microg g(-1), a level reported as potentially lethal to fish and birds that consume them. Seventy-five percent of fish collected in 1997, 90% in 1998, and 64% in 1999 exceeded 4 microg g(-1) selenium, indicating a high potential for toxicity and reproductive effects. However, examination of weight profiles of various species of collected individual fish suggested successful recruitment in spite of selenium concentrations that exceeded published biological effects thresholds for health and reproductive success. This finding suggested that universal application of published guidelines for selenium may be inappropriate or at least may need refinement for systems similar to the Republican River Basin. Additional research is needed to determine the true impact of selenium on fish and wildlife resources in the Basin.

Aluminum output fluxes from forest ecosystems in Europe: a regional assessment

Data from 89 forested catchments and plots across Europe were used to define empirical relationships between aluminum leaching and input fluxes of major ions, output fluxes of major ions, ecosystem parameters such as soil pH, and combinations of these. Forests that release dissolved Al to seepage or surface waters are located primarily in areas receiving the highest loading of acid rain, and the output flux of Al shows the highest correlations to the throughfall flux of inorganic nitrogen, the output fluxes of NO3-, H+, and SO4(2-), and the mineral soil pH. If the speciation of Al is taken to be Al3+ (an overestimate), Al is released in a nearly 1:1 molar charge ratio with the sum of NO3- and SO4(2-) in runoff or seepage water over a wide range of basepoor bedrock types and acid deposition across Europe. The empirical data point to a threshold range of N deposition of 80 to 150 mmolc N m(-2) yr(-1) and a (less clearly defined) range of S deposition of 100 to 200 mmolc SO4(-2) m(-2) yr(-1) above which Al released from forests exceeds 100 mmolc Al m(-2) yr(-1). Within this threshold range, the sites that release little or no dissolved Al are those that continue to assimilate input N and/or have high soil pH (>4.5).

Numerical modelling of dynamic sludge blanket behaviour in secondary clarifiers

New developments in numerical modelling of turbulent and density-affected flow in secondary clarifiers are reported. The sludge blanket is included in the computation domain which allows us to account for sedimentation and resuspension of sludge as well as the growth and diminution of the sludge blanket and at the same time respecting mass conservation. It is shown how strongly the prediction of the sludge-blanket height depends on the approaches to describe the settling behaviour of the sludge and the rheological properties within the sludge blanket. Further, an example of dynamic simulation is presented and discussed. This demonstrates how the sludge blanket behaves during load variation and that instabilities may occur at the interface of sludge blanket and supernatant, potentially resulting in sludge wash-off during transient phases, which is not only during load increase but also during load decrease.

Psychiatric disorders in adult patients with early-treated phenylketonuria

OBJECTIVE

To determine psychiatric disorders in patients with phenylketonuria (PKU) and to test whether biochemical control, intellectual functioning, white matter abnormalities visible on magnetic resonance imaging (MRI), and/or style of parenting influence psychopathology.

DESIGN AND SUBJECTS

This cross-sectional study consisted of 35 PKU patients 17 to 33 years of age (mean: 22.2). From a total of 67 patients, 3 patients were selected because of other causes of possible brain damage. Then 35 patients were randomly drawn with comparison with a control sample (n = 181) from an epidemiologic study.

METHODS

We used a standardized, highly structured, face-to-face interview; intelligence quotient (IQ) test; cranial MRI (n = 26); and monitoring of plasma phenylalanine.

RESULTS

The overall rate of psychiatric disorders was 25.7% in PKU patients and 16.1% in controls. This difference was not statistically significant. The pattern of psychiatric disturbances was different for PKU patients and controls (Fisher's exact test): in PKU patients, externalizing disorders were reduced (PKU: not present, controls: 7.8%), whereas internalizing disorders (PKU: 25.7%, controls: 8.3%) were increased. International Classification of Diseases, version 10, diagnoses were predominantly those of the depressive category and more frequent in women (8 of 18 females and 1 of 17 males). A correlation between IQ and both biochemical control up to 12 years of age and school education of parents was confirmed. No correlation was found between the severity or pattern of psychiatric disturbances and school education of parents, biochemical control, IQ, or the extension of MRI-visible, white matter abnormalities. It was found that a restrictive controlling style of parenting is a risk factor for the development of psychiatric symptoms.

CONCLUSIONS

Our results support a psychological perspective for the development of psychiatric symptoms in PKU. Thus, optimizing medical treatment necessary to prevent brain damage should be accompanied by psychiatric monitoring and psychological support for the families.

Psychopathology of patients treated early for phenylketonuria: results of the German collaborative study of phenylketonuria

At the age of 13 years, 60 adolescents, suffering from phenylalaninemia due to hydroxylase deficiency, and their mothers were simultaneously investigated with a standardized psychiatric interview in order to determine the adolescents' psychiatric status. Forty symptoms related to emotional disorders, antisocial and conduct disorders, hyperkinetic syndromes, and specific symptoms like psychophysiological pains, enuresis, encopresis, tics, stereotypies, and eating disorders were examined. Severity level was rated as undisturbed, mild, moderate, and severe disturbance. Comparison with a representative sample of 191 age mates revealed a double rate of moderate disturbances for the PKU sample. There was no association between severity level and sex as well as mean phenylalanine level during the first 13 years of the patients' lives. No PKU specific diagnosis could be determined. WISC-R-IQ below 90 was associated with a threefold risk of more severe disturbance and patients with more than three adverse familial circumstances had a 50% chance of getting a psychiatric diagnosis. It is concluded that the observed disturbances result from stress associated more with the chronic condition than with the increased phenylalanine level.

Intestinal B cell defects in common variable immunodeficiency

The humoral immune system of the small intestine of 17 patients with common variable immunodeficiency (CVID) was studied by immunohistology using antibodies specific for IgA1,2, IgM, IgG1-4, the J chain and the secretory component (SC). IgA1,2+, IgG2+ and IgM+ lamina propria B cells were totally lacking in 65% (11/17), 41% (7/17) and 18% (3/17) of CVID patients, respectively. One patient exhibited an isolated IgA1 subclass deficiency. The proportion of plasma cells in conventionally stained histological sections of the same intestinal biopsies showed a close correlation with the numbers of IgA+ and IgM+ cells. Considerable numbers of J chain-synthesizing cells were present in all patients with CVID, indicating the presence of early B cells unable to differentiate into immunoglobulin-producing plasma cells. Most of the patients with intestinal IgA and/or IgM defects strongly expressed the SC in their enterocytes, suggesting an immunoglobulin-independent regulation of the SC. Clinically, only CVID patients with intestinal IgA defects developed intestinal infections with Giardia lamblia, Campylobacter jejuni or Candida albicans. The outcome of in vitro immunoglobulin synthesis assays with peripheral blood lymphocytes did not predict the presence or absence of the respective isotype-producing B cells in the intestinal lamina propria. Thus, immunohistological examinations of intestinal biopsies are required to determine the extent of mucosal immunodeficiency in CVID patients.

A diabetes control program in a public health care setting

The Houston Diabetes Control Program is part of an effort by the State of Texas and approximately 30 other programs throughout the United States to ensure that persons with diabetes-related complications receive ongoing state-of-the-art preventive care and treatment. For the past 5 years, this program has served an urban, high-risk patient population with special cultural, ethnic, and economic challenges. The intervention has included the development and implementation of protocols for the prevention and care of diabetes-related complications of the eyes, lower extremities, and cardiovascular system, as well as general management of diabetes and patient and professional education. The program is ongoing in nine community health centers located in low-income neighborhoods of a large metropolitan area. The results thus far indicate an increase in sensitive eye examinations from 8 percent to 26 percent of the patient population, a reduction in incidence of legal blindness from 9.5 to 2.7 per 1,000 during a 4-year period, an increase in foot examinations from 18 percent to 44 percent of the patient population, and 77 percent of hypertensive patients in good control of blood pressure at less than 160 over 95 mmHg (millimeters of mercury). On the average, there have not been significant long-term improvements in weight reduction or blood glucose control. The major challenges for this program are (a) improvement in control of glycemia, hypertension, and cholesterol; (b) more effective diet and physical activity interventions; and (c) more effective education approaches that help patients to understand metabolic and cardiovascular functions. These challenges will require collaboration of health care professionals in constructive and imaginative ways through their unselfish commitment toward common goals.