Combined staging at one stop using MR mammography: evaluation of an extended protocol to screen for distant metastasis in primary breast cancer - initial results and diagnostic accuracy in a prospective study.

PURPOSE: Accurate staging of primary breast cancer is essential for the therapeutic approach. Modern whole-body MR scanners would allow local and distant staging during a single examination. Accordingly, we designed a dedicated protocol for this purpose and prospectively evaluated the diagnostic accuracy. MATERIALS AND METHODS: 65 consecutive breast cancer patients underwent pre-therapeutic MRI (1.5 T). A bilateral breast protocol (axial: T1w/GRE dynamic contrast-enhanced, T2w/TSE; TA: 10 min) was extended to screen for distant metastasis at one stop without repositioning (coronal: T2w/HASTE, T1w/VIBE; FOV: thorax, abdomen and spine; TA: 90 sec; multichannel surface coils). The standard of reference was S3 guideline-compliant staging examinations. Global assessment regarding the presence of distant metastasis was performed independently by two experienced and blinded radiologists (five-level confidence score). Inter-rater agreement (weighted kappa) and observer scoring were analyzed (contingency tables). RESULTS: The prevalence of synchronous metastases was 7.7 % (n = 5). The protocol enabled global assessment regarding the presence of distant metastasis with high accuracy (sensitivity: 100 %; specificity: 98.3 %) and inter-rater agreement (kappa: 0.92). CONCLUSION: Applying the extended MRI protocol, accurate screening for distant metastasis was possible in combination with a dedicated breast examination.

Application of classification trees for the qualitative differentiation of focal liver lesions suspicious for metastasis in gadolinium-EOB-DTPA-enhanced liver MR imaging.

PURPOSE: To evaluate the diagnostic accuracy of qualitative descriptors alone and in combination for the classification of focal liver lesions (FLLs) suspicious for metastasis in gadolinium-EOB-DTPA-enhanced liver MR imaging. MATERIALS AND METHODS: Consecutive patients with clinically suspected liver metastases were eligible for this retrospective investigation. 50 patients met the inclusion criteria. All underwent Gd-EOB-DTPA-enhanced liver MRI (T2w, chemical shift T1w, dynamic T1w). Primary liver malignancies or treated lesions were excluded. All investigations were read by two blinded observers (O1, O2). Both independently identified the presence of lesions and evaluated predefined qualitative lesion descriptors (signal intensities, enhancement pattern and morphology). A reference standard was determined under consideration of all clinical and follow-up information. Statistical analysis besides contingency tables (chi square, kappa statistics) included descriptor combinations using classification trees (CHAID methodology) as well as ROC analysis. RESULTS: In 38 patients, 120 FLLs (52 benign, 68 malignant) were present. 115 (48 benign, 67 malignant) were identified by the observers. The enhancement pattern, relative SI upon T2w and late enhanced T1w images contributed significantly to the differentiation of FLLs. The overall classification accuracy was 91.3 % (O1) and 88.7 % (O2), kappa = 0.902. CONCLUSION: The combination of qualitative lesion descriptors proposed in this work revealed high diagnostic accuracy and interobserver agreement in the differentiation of focal liver lesions suspicious for metastases using Gd-EOB-DTPA-enhanced liver MRI.

Differences in anosmic and normosmic group in bimodal odorant perception: a functional- MRI study.

So-called bimodal odorants are able to stimulate the intranasal trigeminal system at relatively low concentrations. Using them as stimuli, the current study focused on the interaction between the olfactory and trigeminal systems at a cerebral level. In the experiment, menthol was used at two concentrations, low and high, and these were delivered to two groups of subjects, a healthy control group and an anosmic group who were unable to perceive smells. A computer-controlled olfactometer based on principles of air-dilution was used to deliver the stimuli, while the brain functions were assessed by a functional magnetic resonance imaging (fMRI) technique. SPM5 was used for data analysis. The results showed that normosmic subjects exhibited activation in the anterior cingulate cortex (ACC) and posterior cingulate cortex (PCC), prefrontal cortex (PFC), and cerebellum. Whilst anosmic subjects activated the same area inside the anterior cingulate; moreover a cluster of activation was found in the left parahippocampal gyrus. In controls, an effect of stimulus intensity was localized between the anterior cingulated, the medial frontal gyrus and the cerebellum; such areas could not be found in anosmic subjects. These results suggest that the olfactory system modifies trigeminally mediated information causing an evident effect in the differentiation between stimulus intensities.

[Volume alterations in the gray matter of anosmic subjects. Lessons we can learn from voxel-based morphometry]. / Volumenänderungen der grauen Hirnsubstanz bei Anosmikern. Erkenntnisse durch voxelbasierte Morphometrie.

Alterations in the central nervous system in patients with a loss of sense of smell are well documented for the olfactory bulb (OB). Here we present a voxel-based morphometry (VBM) study on cerebral alterations in the gray matter of patients with anosmia above the OB. 3-Tesla MRI datasets were obtained from 17 patients with anosmia as well as from 17 normosmic controls. Data processing and evaluation was performed using the SPM5 software package (Wellcome Department of Imaging Neuroscience Group, London, UK) and the implemented VBM5 toolbox. Patients with anosmia showed a significant volume decrease in the gray matter in the primary olfactory cortex as well as in secondary olfactory areas (insular cortex, orbitofrontal cortex, cingulate cortex and hippocampus). Furthermore, volume decreases in areas like the nucleus accumbens with adjacent subcallosal gyrus and the dorsolateral prefrontal cortex were found. Longer disease duration was associated with more profound alterations in the gray matter. VBM is appropriate to document brain alterations in patients with olfactory disorders.

Identification of the nervus intermedius using 3T MR imaging.

BACKGROUND AND PURPOSE: Improved MR imaging at higher field strengths enables more detailed imaging of cranial nerves. The aim of this study was to assess the identifiability of the NI in the CPA and IAC by using high-resolution 3T MR imaging. MATERIALS AND METHODS: Twenty-seven healthy volunteers (13 men and 14 women; mean age, 33 years) underwent 3T MR imaging of the CPA. The section thicknesses of the CISS sequence was 0.4 mm (TR, 12.18 ms; TE, 6.09 ms) using a 12-channel head coil. Evaluation was performed by using MPR mode. Image quality and identifiability of the NI were rated independently by 2 observers according to predefined criteria on an ordinal scale. Interobserver agreement was assessed by κ statistics. RESULTS: Fifty-four NIs were evaluated. Both observers were able to identify the NI in nearly 60% of cases. It was possible to indentify at least 1 NI in 70% of all volunteers in the CPA and/or IAC. Image quality ratings showed a substantial agreement (κ = 0.65) and identifiability ratings an almost perfect (κ = 0.83) agreement. CONCLUSIONS: Careful evaluation of all nervous and vascular structures in the CPA and IAC at high-resolution 3T MR imaging allows reliable depiction of the NI.

Gray matter alterations in parosmia.

Parosmia is a common olfactory disorder. In this condition, odors are perceived in a different quality than usual. This distorted olfactory percept is typically reported to be unpleasant. Little is known about the pathophysiology of this phenomenon. Previous studies demonstrated smaller volumes of the olfactory bulbs in patients with parosmia compared to subjects without parosmia. In order to investigate structural brain alterations in areas beyond the olfactory bulb, in the current study voxel-based morphometry was applied. A group of 22 parosmic patients was compared with control subjects matched for age- and sex, who exhibited a similar performance in olfactory tests. Performing a whole brain analysis, we found profound gray matter volume loss in the left anterior insula in parosmic patients. In an additional volume of interest analysis including primary and secondary olfactory areas, we also found volume loss in the right anterior insula, the anterior cingulate cortex, the hippocampus bilaterally, and the left medial orbitofrontal cortex. Many of these areas are critically involved in olfactory quality discrimination and odor memory. The present results indicate that reduced gray matter volume in brain regions supporting odor discrimination and memory is related to disturbed olfactory sensation in parosmia.

[Detection of olfactory areas in functional MRI--how many repetitions are necessary?]. / Darstellung olfaktorischer Areale mittels funktionellem MRT--wieviele Reize sind notwendig?

BACKGROUND AND PURPOSE: A useful tool for the investigation of the human olfactory system is functional magnetic resonance tomography (fMRI). Since the length of the fMRI examination is a limiting factor for its usefulness in clinical routine in this study a fast, reliable paradigm should be found in order to reduce the overall examination time and the olfactory habituation. METHODS: A MRI-compatible constant flow olfactometer was developed. 9 healthy normosmic subjects were stimulated 16 times with the odorant phenyl-ethyl-alcohol (PEA) using an event-related design. The statistical evaluation of the data was performed by the MATLAB based SPM5 software package. RESULTS: The group analysis showed cerebral activations within the insula, the adjacent operculum and orbitofrontal cortex bilaterally. Furthermore, bilateral activations were measured in the cingulum, piriform cortex and the cerebellum. All mentioned areas could be already identified after 8 repetitions of odorant condition. Bilateral insular activations and activations in the left piriform cortex were even shown after 4 repetitions. In the single subject analysis, all 9 subjects exhibited insular activity and in 3 subjects showed activation of the piriform cortex after 4 repetitions. CONCLUSION: In olfactory fMRI, stimulus repetition more than 8 did not improve the quality and reliability of the results. Therefore, 4-8 stimuli are expected to be sufficient.

Olfactory bulb ventricles as a frequent finding--a myth or reality? Evaluation using high resolution 3 Tesla magnetic resonance imaging.

Data on the prevalence of persistent olfactory bulb ventricles (OBV) in humans remain contradictory. The aim of this study was to investigate the hypothesis of large cystic-like OBVs filled with cerebrospinal fluid (CSF) as a frequent finding in magnetic resonance imaging (MRI). Fifty normosmic volunteers (25 men and 25 women, mean 40 years) underwent 3 Tesla MRI of the anterior skull base. Normal smell function was determined by testing of the odor threshold discrimination identification score using the Sniffin' Sticks test kit. The voxel size of the constructive interference in steady state (CISS) sequence was 0.4×0.4×0.4 mm (TR 12.18 ms, TE 6.09 ms) using a 12-channel head coil. Image quality was rated by three observers according to predefined criteria on an ordinal scale. Additionally, contrast-to-noise (CNR) and signal-to-noise (SNR) ratios were calculated. Quantitative signal intensity (SI) measurement of olfactory bulb (OB) structures and small Virchow-Robin spaces (VRS) was performed using multi planar reconstruction mode. Ninety-one OBs were eligible for evaluation. Image quality was rated as adequate in 55% and as excellent in 36% of cases. CNR and SNR calculations resulted in values of 21.59 and 19.06, respectively. Wilcoxon signed rank test revealed significant higher SI values for OB center compared to OB surface (P<0.001) and to OB base (P<0.001) but also significant lower SI values compared to small VRS (P<0.001) in 94.5%. In 5.5%, SI measurement revealed signs for CSF-filled structures in the OB. High-resolution 3 Tesla MRI did not verify the hypothesis of large cystic CSF-filled OBVs as a frequent finding although evidence is growing that the hyperintense signal in the center of OBs might be associated with interstitial or finely dispersed CSF/fluid or with tiny, histologically detectable remnants of OBVs.

[Bilateral deafness and unilateral facial nerve palsy as presenting features of Wegener's granulomatosis : a case report]. / Bilaterale Ertaubung und einseitige Fazialisparese als Erstmanifestation eines M. Wegener : Ein Fallbericht.

A 72-year-old female patient presented with otitis of her left ear with inner ear depletion. Despite administration of intravenous antibiotics according to the resistogram and mastoidectomy the patient developed a similar pathological condition in the right ear and facial nerve palsy on the left side. Treatment with trimethoprim/sulfamethoxazole under the working diagnosis of a localised seronegative Wegener's granulomatosis was initiated without achieving remission. Cyclophosphamide pulse therapy in combination with high-dose methylprednisolone was initiated with rapid cure of the bilateral otitis. Sensorineural hearing loss and facial nerve palsy remained irreversible.

[CT and MR imaging of the facial nerve]. / Computer- und Magnetresonanztomographie des N. facialis.

Modern imaging techniques used for depicting the facial nerve include multi-slice spiral computed tomography (CT) and high-field magnetic resonance imaging (MRI). CT is the gold standard for imaging the osseous structures of the temporal bone. As a result of its excellent soft tissue contrast, MRI enables identification of the facial nerve itself. Due to high spatial resolution and the possibility to generate multiplanar reconstructions, both CT and MRI facilitate an exact evaluation of anatomical structures in all three spatial planes. The present article provides an overview of relevant anatomical structures, a thorough knowledge of which is the basic prerequisite to understanding pathologies and interpreting radiological findings correctly. Furthermore, basic techniques and strategies for imaging the facial nerve using CT and MRI are explained in general. The articles concludes with specific requirements for the radiological diagnosis of dysplasia, neoplasms and trauma, as well as vascular and inflammatory diseases.

[Diagnostic and therapy of salivary gland diseases: relevant aspects for the pathologist from the clinical perspective]. / Diagnostik und Therapie von Speicheldrüsenerkrankungen: Relevantes für den Pathologen aus Sicht der Klinik.

Significant progress in the diagnosis and therapy of salivary gland diseases has been made in recent years. The new technique of diagnostic and interventional sialendoscopy has made an important contribution and is indicated in every case of obstructive sialadenitis. The number of open resections of salivary glands due to stones will clearly decrease in the future in favor of endoscopic removal. Due to recent publications on the appropriate extent of salivary gland resection in benign tumors, more and more specimens with reduced cuffs of healthy salivary gland tissue will be sent to the pathologists. Ultrasound will stay the procedure of first choice for imaging of salivary gland diseases in Germany. In combination with fine-needle aspiration cytology high sensitivity and specificity for the assessment of salivary gland tumors can be achieved. Diffusion-weighted magnetic resonance imaging (MRI) is a new imaging tool and the power of distinction of pleomorphic adenoma from malignant tumors is promising. The use of botulinum toxin for salivary glands diseases is increasing. Intraglandular injections have been shown to induce salivary gland atrophy in animal experiments. The availability of biologicals is currently yielding new aspects for the treatment of Sjögren's disease.

[3D-Visualisation of the middle ear by computer-assisted post-processing of helical multi-slice CT data]. / 3D-Darstellung des Mittelohres mittels computergestützter Nachverarbeitung helikaler Mehrschicht-CT-Daten.

Post-processing of CT-data allows non-invasive 3D-Visualisation of the middle ear for diagnosis and surgical planning. In this study different post-processing techniques and the clinical application of a 3D-postprocessing algorithm in a large number of patients are presented. 20 normal patients, 6 dissected temporal bones and 213 patients with suspected middle ear pathology were examined using a low-dosage Multi-Slice CT protocol. Virtual endoscopic views of the middle ear and 3D-images of the ossicles were generated using a standardised algorithm. Evaluation of the image quality was performed. The virtual views of the dissected temporal bones were compared to real views. In 32 patients high-quality 3D-models of the individual anatomical structures were generated and displayed using different visualisation techniques. The standardised and evaluated method enabled visualisation of the normal middle ear anatomy. Assessment of different pathologies, especially malformation, trauma, implants and postoperative alterations, was facilitated. The high-quality 3D-models allowed precise imaging of the anatomical structures. 3D-Visualisation of the middle ear using CT-data is beneficial for radiological diagnosis and surgical planning in cases of complex middle ear pathology as a complementary examination technique.