Intratumoral heterogeneity after targeted therapy in murine cancer models with differing degrees of malignancy

INTRODUCTION

Conventional morphologic and volumetric assessment of treatment response is not suitable for adequately assessing responses to targeted cancer therapy. The aim of this study was to evaluate changes in tumor composition after targeted therapy in murine models of breast cancer with differing degrees of malignancy via non-invasive magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Mice bearing highly malignant 4T1 tumors or low malignant 67NR tumors were treated with either a combination of two immune checkpoint inhibitors (ICI, anti-PD1 and anti-CTLA-4) or the multi-tyrosine kinase inhibitor sorafenib, following experiments with macrophage-depleting clodronate-loaded liposomes and vessel-stabilizing angiopoietin-1. Mice were imaged on a 9.4 T small animal MRI system with a multiparametric (mp) protocol, comprising T1 and T2 mapping and diffusion-weighted imaging. Tumors were analyzed ex vivo with histology.

RESULTS AND DISCUSSIONS

All treatments led to an increase in non-viable areas, but therapy-induced intratumoral changes differed between the two tumor models and the different targeted treatments. While ICI treatment led to intratumoral hemorrhage, sorafenib treatment mainly induced intratumoral necrosis. Treated 4T1 tumors showed increasing and extensive areas of necrosis, in comparison to 67NR tumors with only small, but also increasing, necrotic areas. After either of the applied treatments, intratumoral heterogeneity, was increased in both tumor models, and confirmed ex vivo by histology. Apparent diffusion coefficient with subsequent histogram analysis proved to be the most sensitive MRI sequence. In conclusion, mp MRI enables to assess dedicated therapy-related intratumoral changes and may serve as a biomarker for treatment response assessment.

Sex-specifics of ECT outcome

OBJECTIVE

Electroconvulsive therapy (ECT) is the most effective treatment for patients with severe major depressive disorder (MDD). Given the known sex differences in MDD, improved knowledge may provide more sex-specific recommendations in clinical guidelines and improve outcome. In the present study we examine sex differences in ECT outcome and its predictors.

METHODS

Clinical data from 20 independent sites participating in the Global ECT-MRI Research Collaboration (GEMRIC) were obtained for analysis, totaling 500 patients with MDD (58.6 % women) with a mean age of 54.8 years. Severity of depression before and after ECT was assessed with validated depression scales. Remission was defined as a HAM-D score of 7 points or below after ECT. Variables associated with remission were selected based on literature (i.e. depression severity at baseline, age, duration of index episode, and presence of psychotic symptoms).

RESULTS

Remission rates of ECT were independent of sex, 48.0 % in women and 45.7 % in men (X²(1) = 0.2, p = 0.70). In the logistic regression analyses, a shorter index duration was identified as a sex-specific predictor for ECT outcome in women (X²(1) = 7.05, p = 0.01). The corresponding predictive margins did show overlapping confidence intervals for men and women.

CONCLUSION

The evidence provided by our study suggests that ECT as a biological treatment for MDD is equally effective in women and men. A shorter duration of index episode was an additional sex- specific predictor for remission in women. Future research should establish whether the confidence intervals for the corresponding predictive margins are overlapping, as we find, or not.

Forensische Altersdiagnostik mittels Niederfeld-Magnetresonanztomographie

Hintergrund

Ein rechtlich zulässiges medizinisches Altersfeststellungsverfahren mit möglichst schonenden und zuverlässigen Methoden bei unbegleiteten und fraglich minderjährigen Ausländern ist erforderlich, um den tatsächlich Minderjährigen den für sie gesetzlich vorgesehenen besonderen Schutz zukommen zu lassen.

Ziel der Arbeit

Studiendesign und erste Ergebnisse einer Studie zur forensischen Altersdiagnostik mittels Niederfeld-Magnetresonanztomographie werden vorgestellt.

Material und Methoden

Geplant ist die prospektive Untersuchung von 650 Studienteilnehmenden, gleichmäßig verteilt innerhalb der Altersgruppe 12 bis 24 Jahre zu je 25 Personen je Geschlecht. Es sollen Entwicklungsstadien von distalem Radius, distaler Ulna, distalem Femur und proximaler Tibia mithilfe eines 0,31-Tesla(T)-Niederfeld-MRT-Scanners erfasst und mittels Anwendung der Vieth-Klassifikation ausgewertet werden.

Ergebnisse

Nach Auswertung der Untersuchungen der bisher 487 untersuchten Studienteilnehmenden ist ersichtlich, dass die gewählten Sequenzen die für die Vieth-Klassifikation relevanten Charakteristika der Ossifikation der untersuchten Epiphysen erfassen. Die Untersuchungen erweisen sich überdies als einfach in der Durchführung.

Schlussfolgerung

Untersuchungen zur forensischen Altersschätzung am Lebenden unter Anwendung der Vieth-Klassifikation sind mit Niederfeld-MRT-Scannern bei einer Feldstärke von 0,31 T durchführbar. Es bleibt zu klären, ob die mit einem 0,31-T-Niederfeld-MRT-Scanner nachweisbaren Ossifikationsmerkmale am Handgelenk und am Knie einen zweifelsfreien Volljährigkeitsnachweis erlauben.

[Impact of anamnestic information and neurological deficits on the detection rate of secondary headaches]

PURPOSE

Headaches are a very common symptom and imaging is important to rule out symptomatic causes. For clinical differentiation between primary and secondary headaches an exact anamnesis and neurological examination are important. The aim of this study is therefore to identify anamnestic and neurological information that is associated with secondary headaches. Moreover, this study gives an overview of the causes and differential diagnoses of secondary headaches.

METHODS

We performed a retrospective analysis of 239 patients ≥18 years with headaches who had undergone computed tomography or magnetic resonance imaging. The impact of basic characteristics such as age and gender as well as anamnestic (pain intensity, thromboembolic risk profile) and clinical information (neurological deficit, papilledema, reduced vigilance) was tested by χ² test at the significance level p < 0.05.

RESULTS

In all, 27 of the included patients (11.3%) showed intracranial pathologies that required treatment. The most frequent pathologies were intracranial hypertension (9 patients), cerebral mass lesions (7 patients) and thrombosis of the cranial sinus/veins (3 patients). There was a significant association of a pathologic imaging finding and neurological deficits (p = 0.001) and a papilledema (p < 0.001). Reduced vigilance, pain intensity and thromboembolic risk factors as well as age and gender showed no significant association.

CONCLUSIONS

A neurological deficit and especially papilledema are hints towards secondary headaches and should result in computed tomography or magnetic resonance imaging. Other factors such as reduced vigilance, pain intensity, age and gender have no relevant impact on the occurrence of intracranial pathologies.

Staging in childhood lymphoma

Aim: The clinical value of positron emission tomography using fluorine-18 fluoro-deoxy-glucose (FDG-PET) in the staging of adult lymphoma has been shown in many studies. However, there are only few data regarding childhood lymphoma. The purpose of this retrospective study was to compare the staging of childhood lymphoma using FDG-PET and the established computed tomography (CT). Method: Whole-body FDG-PET was performed in 25 children with histologically proven Hodgkin ´s disease (n = 18) and non-Hodgkin´s lymphoma (n = 7) using a dedicated PET. The findings were compared with the CT results. Both examinations, FDG-PET and CT, were assessed by two experienced physicians. In each patient, 30 regions were analysed (22 nodal, 8 extranodal). Each region was assessed using a fivevalue scale (definitely/probably positive, equivocal, probably/definitely negative). Results: 662 regions (470 nodal, 192 extranodal) were compared. 91 regions (81 nodal, 10 extranodal; 14%) were concordant positive and 517 regions (347 nodal, 170 extranodal; 78%) were concordant negative. In 47 regions, 48 discordant findings (7%) were described: 27 findings (22 nodal, 5 extranodal) were positive using FDG-PET and negative using CT whereas 21 findings (17 nodal, 4 extranodal) were positive using CT and negative using PET. A total of 7 regions (1%) were judged equivocal in one imaging modality (1 FDG-PET, 6 CT). Using FDG-PET as compared to CT, resulted in a higher staging in 4 of 25 patients and in a lower staging in 2 of 25 patients. Conclusion: Staging of childhood lymphoma using FDGPET shows differences compared with CT resulting in a different staging in 6 of 25 patients. Prospective studies are required to evaluate the impact of these discrepancies on the clinical management of pediatric patients.

Whole-body imaging of oncologic patients using 16-channel PET-CT

Aim: This study evaluated a MDCT protocol for contrast-enhanced 16-channel PET-CT with regard to scan range and duration of a whole-body 18F-FDG PET-CT examination, the occurrence of contrast-material induced artefacts and quantitative assessment of CT attenuation. Patients, methods: 205 patients (51.9 ± 12.4 years) with different malignant tumours underwent whole-body PET-CT; the study protocol had been approved by the institutional review board. Contrast-enhanced MDCT (16 ˟ 1.5 mm; 120 ml Iomeprol 3 ml/s, 50 ml saline chaser bolus, scan delay 70 s; oral contrast) was also used for attenuation correction. From MDCT data mean scan range and duration, occurrence of contrast media-induced artefacts, and mean CT densities of jugular (jv) and subclavian (scv), superior (vcs) and inferior (vci) caval, portal (pv), and bilateral external iliac veins, pulmonary (ap) and iliac arteries, descending thoracic and abdominal aorta, all cardiac chambers, as well as both liver lobes, spleen, adrenal glands and kidneys were determined. Results: Attenuation corrected PET images were free of contrast media-related image artefacts. Homogeneous contrast enhancement was found in the mediastinal veins (right/left jv 171 ± 34/171 ± 35, scv 127 ± 50/127 ± 40, vcs 153 ± 36 HU) and arteries (e.g. ap 145 ± 26/151 ± 26). Cardiac chambers, abdominal vessels (e.g. vci 138 ± 24, pv 159 ± 25 HU), and parenchymal organs revealed sufficient and homogenous contrast-enhancement in all cases. No beam-hardening artefacts occurred in the neighbourhood of the subclavian veins. Conclusion: The chosen whole-body 18F-FDG 16-slice PET-CT protocol allowed for craniocaudal CT scanning with high vessel and parenchymal contrast revealing no IV contrast-media induced artefacts in attenuation-corrected PET data sets.

Effects of electroconvulsive therapy on amygdala function in major depression - a longitudinal functional magnetic resonance imaging study

BACKGROUND

Electroconvulsive therapy (ECT) is one of the most effective treatments for severe depression. However, little is known regarding brain functional processes mediating ECT effects.

METHOD

In a non-randomized prospective study, functional magnetic resonance imaging data during the automatic processing of subliminally presented emotional faces were obtained twice, about 6 weeks apart, in patients with major depressive disorder (MDD) before and after treatment with ECT (ECT, n = 24). Additionally, a control sample of MDD patients treated solely with pharmacotherapy (MED, n = 23) and a healthy control sample (HC, n = 22) were obtained.

RESULTS

Before therapy, both patient groups equally showed elevated amygdala reactivity to sad faces compared with HC. After treatment, a decrease in amygdala activity to negative stimuli was discerned in both patient samples indicating a normalization of amygdala function, suggesting mechanisms potentially unspecific for ECT. Moreover, a decrease in amygdala activity to sad faces was associated with symptomatic improvements in the ECT sample (r spearman = -0.48, p = 0.044), and by tendency also for the MED sample (r spearman = -0.38, p = 0.098). However, we did not find any significant association between pre-treatment amygdala function to emotional stimuli and individual symptom improvement, neither for the ECT sample, nor for the MED sample.

CONCLUSIONS

In sum, the present study provides first results regarding functional changes in emotion processing due to ECT treatment using a longitudinal design, thus validating and extending our knowledge gained from previous treatment studies. A limitation was that ECT patients received concurrent medication treatment.

Cortical abnormalities in adults and adolescents with major depression based on brain scans from 20 cohorts worldwide in the ENIGMA Major Depressive Disorder Working Group

The neuro-anatomical substrates of major depressive disorder (MDD) are still not well understood, despite many neuroimaging studies over the past few decades. Here we present the largest ever worldwide study by the ENIGMA (Enhancing Neuro Imaging Genetics through Meta-Analysis) Major Depressive Disorder Working Group on cortical structural alterations in MDD. Structural T1-weighted brain magnetic resonance imaging (MRI) scans from 2148 MDD patients and 7957 healthy controls were analysed with harmonized protocols at 20 sites around the world. To detect consistent effects of MDD and its modulators on cortical thickness and surface area estimates derived from MRI, statistical effects from sites were meta-analysed separately for adults and adolescents. Adults with MDD had thinner cortical gray matter than controls in the orbitofrontal cortex (OFC), anterior and posterior cingulate, insula and temporal lobes (Cohen's d effect sizes: -0.10 to -0.14). These effects were most pronounced in first episode and adult-onset patients (>21 years). Compared to matched controls, adolescents with MDD had lower total surface area (but no differences in cortical thickness) and regional reductions in frontal regions (medial OFC and superior frontal gyrus) and primary and higher-order visual, somatosensory and motor areas (d: -0.26 to -0.57). The strongest effects were found in recurrent adolescent patients. This highly powered global effort to identify consistent brain abnormalities showed widespread cortical alterations in MDD patients as compared to controls and suggests that MDD may impact brain structure in a highly dynamic way, with different patterns of alterations at different stages of life.

Prefrontal gray matter volume mediates genetic risks for obesity

Genetic and neuroimaging research has identified neurobiological correlates of obesity. However, evidence for an integrated model of genetic risk and brain structural alterations in the pathophysiology of obesity is still absent. Here we investigated the relationship between polygenic risk for obesity, gray matter structure and body mass index (BMI) by the use of univariate and multivariate analyses in two large, independent cohorts (n=330 and n=347). Higher BMI and higher polygenic risk for obesity were significantly associated with medial prefrontal gray matter decrease, and prefrontal gray matter was further shown to significantly mediate the effect of polygenic risk for obesity on BMI in both samples. Building on this, the successful individualized prediction of BMI by means of multivariate pattern classification algorithms trained on whole-brain imaging data and external validations in the second cohort points to potential clinical applications of this imaging trait marker.

The impact of lesion location on dysphagia incidence, pattern and complications in acute stroke. Part 2: Oropharyngeal residue, swallow and cough response, and pneumonia

BACKGROUND AND PURPOSE

Dysphagia is a well-known complication of acute stroke. Given the complexity of cerebral swallowing control it is still difficult to predict which patients are likely to develop swallowing dysfunction based on their neuroimaging. In Part 2 of a comprehensive voxel-based imaging study, whether the location of a stroke lesion can be correlated with further dysfunctional swallowing patterns, pulmonary protective reflexes and pneumonia was evaluated.

METHODS

In all, 200 acute stroke cases were investigated applying flexible endoscopic evaluation of swallowing within 96 h from admission. Lesions were mapped using patients' computed tomography/magnetic resonance images and these were registered to a standard space. The percentage of lesioned volume of 137 anatomically defined brain regions was determined on a voxel basis (FSL5.0). Region-specific odds ratios (ORs) were calculated with respect to the presence of oropharyngeal residue, delayed swallow response, insufficient cough reflex and occurrence of pneumonia during hospital stay. Colour-coded lesion location maps of brain regions with significant ORs were created (P < 0.05).

RESULTS

Lesion maps for residue and impaired swallow response depicted parietal-temporal areas of the right hemisphere. Limbic structures in the right hemisphere and sensory regions on the left were associated with cough reflex disturbance. There was no overlap of lesion maps for impaired swallow response and insufficient cough reflex or pneumonia, but substantial overlap between the last two conditions.

CONCLUSIONS

This study gives new insights on the cortical representation of single components of swallowing and airway protection behaviours. The lesion model may help to risk-stratify patients for dysphagia and pneumonia based on their brain scan.

Pneumatic Distension of Ventricular Mural Architecture Validated Histologically

Purpose: There are ongoing arguments as to how cardiomyocytes are aggregated together within the ventricular walls. We used pneumatic distension through the coronary arteries to exaggerate the gaps between the aggregated cardiomyocytes, analyzing the pattern revealed using computed tomography, and validating our findings by histology. Methods: We distended 10 porcine hearts, arresting 4 in diastole by infusion of cardioplegic solutions, and 4 in systole by injection of barium chloride. Mural architecture was revealed by computed tomography, measuring also the angulations of the long chains of cardiomyocytes. We prepared the remaining 2 hearts for histology by perfusion with formaldehyde. Results: Increasing pressures of pneumatic distension elongated the ventricular walls, but produced insignificant changes in mural thickness. The distension exaggerated the spaces between the aggregated cardiomyocytes, compartmenting the walls into epicardial, central, and endocardial regions, with a feathered arrangement of transitions between them. Marked variation was noted in the thicknesses of the parts in the different ventricular segments, with no visible anatomical boundaries between them. Measurements of angulations revealed intruding and extruding populations of cardiomyocytes that deviated from a surface-parallel alignment. Scrolling through the stacks of tomographic images revealed marked spiraling of the aggregated cardiomyocytes when traced from base to apex. Conclusion: Our findings call into question the current assumption that cardiomyocytes are uniformly aggregated together in a tangential fashion. There is marked heterogeneity in the architecture of the different ventricular segments, with the aggregated units never extending in a fully transmural fashion. Key Points: • Pneumographic computed tomography reveals an organized structure of the ventricular walls.• Aggregated cardiomyocytes form a structured continuum, with marked regional heterogeneity.• Global ventricular function results from antagonistic forces generated by aggregated cardiomyocytes. Citation Format: • Burg MC, Lunkenheimer P, Niederer P et al. Pneumatic Distension of Ventricular Mural Architecture Validated Histologically. Fortschr Röntgenstr 2016; 188: 1045 - 1053.

TNF receptors 1 and 2 exert distinct region-specific effects on striatal and hippocampal grey matter volumes (VBM) in healthy adults

Tumour necrosis factor alpha (TNFα) has been implicated in the pathophysiology of neurodegenerative and neuropsychiatric disease, with research highlighting a role for TNFα in hippocampal and striatal regulation. TNFα signals are primarily transduced by TNF receptors 1 and 2 (TNFR1 and TNFR2), encoded by TNFRSF1A and TNFRSF1B, which exert opposing effects on cell survival (TNFR1, neurodegenerative; TNFR2, neuroprotective). We therefore sought to explore the respective roles of TNFR1 and TNFR2 in the regulation of hippocampal and striatal morphology in an imaging genetics study. Voxel-based morphometry was used to analyse the associations between TNFRSF1A (rs4149576 and rs4149577) and TNFRSF1B (rs1061624) genotypes and grey matter structure. The final samples comprised a total of 505 subjects (mean age = 33.29, SD = 11.55 years; 285 females and 220 males) for morphometric analyses of rs1061624 and rs4149576, and 493 subjects for rs4149577 (mean age = 33.20, SD = 11.56 years; 281 females and 212 males). Analyses of TNFRSF1A single nucleotide polymorphisms (SNPs) rs4149576 and rs4149577 showed highly significant genotypic associations with striatal volume but not the hippocampus. Specifically, for rs4149576, G homozygotes were associated with reduced caudate nucleus volumes relative to A homozygotes and heterozygotes, whereas for rs4149577, reduced caudate volumes were observed in C homozygotes relative to T homozygotes and heterozygotes. Analysis of the TNFRSF1B SNP rs1061624 yielded a significant association with hippocampal but not with striatal volume, whereby G homozygotes were associated with increased volumes relative to A homozygotes and heterozygotes. Our findings indicate a role for TNFR1 in regulating striatal but not hippocampal morphology, as well as a complementary role for TNFR2 in hippocampal but not in striatal morphology.

Cine Phase Contrast Angiography of Normal and Diseased Peripheral Arteries

Cine phase contrast angiography (PCA) is a modified MR phase contrast sequence that acquires up to 22 coronal phase images per mean cardiac cycle. The ability of the sequence to visualise local haemodynamics was investigated in 7 normal volunteers and 9 patients with flow disturbances of the peripheral arteries using a 1.5 T imager. Functional flow information provided by coronal cine PCA was correlated with quantitative data obtained by MR flow measurements and vessel morphology confirmed by conventional angiograms. Due to the yet suboptimal image quality, an aortic dissection and 1 of 4 aneurysms could not be depicted morphologically. The temporal pattern of arterial perfusion in cine PCA corresponded with flow velocity versus time data provided by quantitative MR flow measurements. Accuracy and time resolution of cine PCA was thus sufficient to provide functional information on the severity of occlusive vascular disease.

Assessment of coronary arterial stents by multislice-CT angiography

Purpose: To assess patency and lumen visibility of coronary artery stents by multislice-CT angiography (MSCTA) in comparison with conventional coronary angiography as the standard of reference.

Material and Methods: 47 stents of 13 different types were evaluated in 29 patients. MSCTA was performed on a 4-slice scanner with a standard coronary protocol (detector collimation 4 × 1 mm; table feed 1.5 mm/rotation, 400 mAs, 120 kV). Image evaluation was performed by two readers who were blinded to the reports from the catheter angiography. MIP reconstructions were evaluated for image quality on a 4-point scale (1 = poor, 4 = excellent) and stent patency (contrast distal to the stent as an indirect patency sign). Axial images and multiplanar reformations through the stents were used for assessment of stent lumen visibility (measurement of the visible stent lumen diameter) and detection of relevant in-stent stenosis (≥50%).

Results: Image quality was fair to good on average (score 2.64 ± 1.0) and depended on the heart rate (heart rate 45–60: average score 3.2, heart rate 61–70: average score 2.8, heart rate >71: average score 1.4). Thirty-seven stents were correctly classified as patent, 1 was correctly classified as occluded and 9 stents were not assessible due to insufficient image quality because of triggering artifacts. Parts of the stent lumen could be visualized in 30 cases. On average, 20–40% of the stent lumen diameter was visible. Twenty-five stents were correctly classified as having no stenosis, 1 was falsely classified as stenosed, 1 was correctly classified as occluded. In 20 stents lumen visibility was not sufficient for stenosis evaluation.

Conclusion: Although the stent lumen may be partly visualized in most stents, a reliable evaluation of in-stent stenoses does not seem practical by 4-slice MSCT. Nevertheless, for stent patency evaluation, MS-CTA might provide valuable clinical information. With submillimeter MSCT (e.g., 16-slice scanners) and more sophisticated reconstruction algorithms, further improvements may be expected.

Undetected Dural Leaks Complicated by Accidental Drainage of Cerebrospinal Fluid (CSF) can Lead to Severe Neurological Deficits

PURPOSE

Intracranial hypotension has been reported as a complication of accidental drainage after surgical treatment in several cases. Application of negative pressure systems (wound drains, VAC(®)-therapy, chest tube drainage) had typically led to severe intracranial hypotension including intracranial hemorrhage and tonsillar herniation. In the last year the authors observed 2 cases of accidental spinal drainage of CSF in patients with neurological deficits, regressing after reduction of the device suction.

MATERIAL AND METHODS

We conducted a systematic PubMed-based research of the literature to study the variety and frequency of the reported symptoms from 1st of January 1980 until 1st of October 2015.

RESULTS

Reviewing the literature 24 relevant citations including 27 reported cases of posttraumatic or postoperative loss of CSF leading to neurological symptoms were identified. All 15 reported cases in which a negative pressure suction device had been applied showed severe neurological and radiological symptoms such as coma or brain herniation and intracranial hemorrhage. In all cases patients recovered rapidly after removal of the suction device. Milder symptoms were observed in the patients without negative pressure suction, mainly only presenting with headaches or cranial nerve involvement.Additionally, we give an overview about current recommendations regarding cranial and spinal imaging to rule out dural laceration and cranial hypotension.

CONCLUSION

Patients with dural laceration complicated by accidental drainage of CSF can present with life-threatening conditions. Increasing use of negative pressure suction devices makes the reported condition an important differential diagnosis. A precise radiological examination can help to rule out dural laceration and intracranial hypotension.

KEY POINTS

• Undetected dural laceration complicated by negative pressure suction drains can induce life-threatening symptoms.• Increasing use of negative pressure suction devices makes the reported condition an important differential diagnosis for radiologists Citation Format: • Sporns PB, Schwindt W, Cnyrim CD et al. Undetected Dural Leaks Complicated by Accidental Drainage of Cerebrospinal Fluid (CSF) can Lead to Severe Neurological Deficits. Fortschr Röntgenstr 2016; 188: 451 - 458.

Differing brain structural correlates of familial and environmental risk for major depressive disorder revealed by a combined VBM/pattern recognition approach

BACKGROUND

Neuroimaging traits of either familial or environmental risk for major depressive disorder (MDD) have been interpreted as possibly useful vulnerability markers. However, the simultaneous occurrence of familial and environmental risk might prove to be a major obstacle in the attempt of recent studies to confine the precise impact of each of these conditions on brain structure. Moreover, the exclusive use of group-level analyses does not permit prediction of individual illness risk which would be the basic requirement for the clinical application of imaging vulnerability markers. Hence, we aimed to distinguish between brain structural characteristics of familial predisposition and environmental stress by using both group- and individual-level analyses.

METHOD

We investigated grey matter alterations between 20 healthy control subjects (HC) and 20 MDD patients; 16 healthy first-degree relatives of MDD patients (FH+) and 20 healthy subjects exposed to former childhood maltreatment (CM+) by using a combined VBM/pattern recognition approach.

RESULTS

We found similar grey matter reductions in the insula and the orbitofrontal cortex in patients and FH+ subjects and in the hippocampus in patients and CM+ subjects. No direct overlap in grey matter alterations was found between FH+ and CM+ subjects. Pattern classification successfully detected subjects at risk for the disease even by strictly focusing on morphological traits of MDD.

CONCLUSIONS

Familial and environmental risk factors for MDD are associated with differing morphometric anomalies. Pattern recognition might be a promising instrument in the search for and future application of vulnerability markers for MDD.

Selective arterial Embolisation of Aneurysmal Bone Cysts of the Sacrum: a promising Alternative to Surgery

PURPOSE

The sacrum is a rare but unfavourable location for Aneurysmal Bone Cysts (ABCs), surgical procedures aiming to achieve local tumour control can be mutilating. Aim of this study was to evaluate whether selective arterial embolisation (AE) of ABC of the sacrum is an effective treatment and might be an alternative to surgical treatment options.

MATERIALS AND METHODS

Between 2007 and 2011 six patients (mean age 13.7 years, range 8 - 18 years) with an ABC of the sacrum were treated by AE. Follow-up was performed by MRI-scans as well as clinical examination (mean 36.5 months, range 14 - 56 months).

RESULTS

No treatment related complications have been observed. AE resulted in devascularisation of ABC and led to local tumour control in all patients. A partial consolidation was noticed in three patients. Pain relief was achieved in five of six patients, neurological deficits dissolved. In two patients more than one embolization was necessary. In one of these patients due to exacerbation of pain a surgical decompression was performed.

CONCLUSION

AE of sacral ABCs can serve as an effective and safe treatment option. Thus it might be an alternative to potentially harmful surgical procedures. In case of ongoing tumour growth or pain recurrence AE can be repeated. In case of treatment failure surgical interventions are still possible.

KEY POINTS

• transarterial embolisation enables local tumour control in sacral ABCs. • transarterial embolisation of sacral ABCs is a safe procedure. • in case of tumour progression repetitive embolisations are possible and effective.

Reduction of Advanced Breast Cancer Stages at Subsequent Participation in Mammography Screening

PURPOSE

The decline in advanced breast cancer stages is presumably the most relevant surrogate parameter in mammography screening. It represents the last step in the causal cascade that is expected to affect breast cancer-related mortality. To assess the effectiveness of population-based screening, we analyzed the 2-year incidence rates of advanced breast cancers between women participating in the initial and in the first subsequent round.

MATERIALS AND METHODS

The study included data from 19,563 initial and 18,034 subsequent examinations of one digital screening unit (2008 - 2010). Data on tumor stages, detected by screening or within the following interval of two years (2-year incidence), were provided by the epidemiological cancer registry. Rates of all and combined UICC stages 2, 3 and 4 (advanced stages) were reported for a two-year period. Proportions were tested for significance by using chi-square tests (p < 0.001).

RESULTS

The 2-year incidence rate of all stages was significantly lower in participants in subsequent screening than in initial screening (0.85 vs. 1.29 per 100 women (%); p < 0.0001). A significantly lower 2-year incidence of advanced stages was observed for subsequent screening compared to initial screening (0.26 % vs. 0.48 %; p = 0.0007). Among women aged 50 to 59 years, the incidence of advanced stages was less clearly different (0.21 % vs. 0.35 %; p = 0.07) than in women aged 60 to 69 years (0.31 % vs. 0.70 %; p = 0.0008).

CONCLUSION

During the change from prevalent to incident phase mammography screening, a program impact is seen by a lower 2-year incidence of advanced breast cancers within subsequent compared to initial participants, predominately in women aged 60 to 69 years.

KEY POINTS

• The incidence of advanced tumor stages represents the most relevant surrogate parameter for screening effectiveness. • For the first time the 2-year incidence of advanced breast cancer stages after subsequent mammography screening was analyzed. • We observed a significant effect of screening on the 2-year incidence of advanced stages, predominately in the age group 60 to 69 years.

xPIPE--Reception of DICOM Data from any Sender via the Internet

PURPOSE

Various technologies have been established for DICOM data exchange in radiology. In addition to the patient CD, online transfers via VPN (virtual private network) or DICOM email are common practice. However, dedicated network solutions are generally not appropriate for data exchange with occasional and spontaneous partners due to missing infrastructure at the partner institutions and/or complex setup procedures. The purpose was to develop a practical solution to complement the established technologies to allow users worldwide to transfer images without registration.

MATERIALS AND METHODS

The development of the xPIPE system is based on Java and various software libraries. A client hosted on a website enables sending DICOM data to a receiving system of the hospital.

RESULTS

The new xPIPE system creates a gateway to a receiving hospital which is accessible from any point worldwide, giving other hospitals, clinics and patients a simple and secure method to transmit DICOM data without intermediate storage on external servers.

CONCLUSION

The system was deployed at the University Hospital Münster and subsequently widely used even without information events and training. Data protection during transfer is ensured by the use of signatures and encryption. From the user's perspective the system has only minor technical requirements and can be used with minimal setup effort.

CTP-Based Tissue Outcome: Promising Tool to Prove the Beneficial Effect of Mechanical Recanalization in Acute Ischemic Stroke

PURPOSE

To prove the tissue-protecting effect of mechanical recanalization, we assessed the CT perfusion-based tissue outcome ("TO") and correlated this imaging parameter with the 3-month clinical outcome ("CO").

MATERIALS AND METHODS

159 patients with large intracranial artery occlusions revealing mechanical recanalization were investigated by CCT, CT angiography (CTA) and CT perfusion (CTP) upon admission. For the final infarct volume, native CCT was repeated after 24 h. The "TO" ("percentage mismatch loss" = %ML) was defined as the difference between initial penumbral tissue on CTP and final infarct volume on follow-up CCT. We monitored the three-month modified Rankin Scale (mRS), age, bleeding occurrence, time to recanalization, TICI score and collateralization grade, infarct growth and final infarct volume. Spearman's correlation and nominal regression analysis were used to evaluate the impact of these parameters on mRS. 

RESULTS

Significant correlations were found for %ML and mRS (c = 0.48, p < 0.001), for final infarct volume and mRS (c = 0.52, p < 0.001), for TICI score and mRS (c = - 0.35, p < 0.001), for initial infarct core and mRS (c = 0.14, p = 0.039) as well as for age and mRS (c = 0.37, p < 0.001). According to the regression analysis, %ML predicted the classification of mRS correctly in 38.5 % of cases. The subclasses mRS 1 and 6 could be predicted by %ML with 86.4 % and 60.9 % reliability, respectively. No correlations were found for time to recanalization and mRS, for collateralization grade and mRS, and for post-interventional bleeding and mRS. 

CONCLUSION

Better than the TICI score, CT-based TO predicts the clinical success of mechanical recanalization, showing that not recanalization, but reperfusion should be regarded as a surrogate parameter for stroke therapy.

KEY POINTS

• %ML as well as the final infarct volume can make a direct point about the immediate effect of successful mechanical recanalization.• The clinical outcomes after mechanical recanalization are reliably predicted by %ML, reflecting the benefit of escalation therapy including interventional reopening of parent vessel occlusions.• Not recanalization but rather reperfusion should be regarded as a surrogate parameter for successful stroke therapy.