Josef Simbrunner

Pathways in the diagnosis of prevertebral tendinitis

INTRODUCTION The prevertebral tendinitis is an inflammatory process, which affects the cervicothoracic prevertebral muscles. This extremely rare entity was first described by Hartley and Fahlgren in 1964 and until now there are just some case reports dealing with this process. Unfortunately it is quite easy to misdiagnose or mistake the prevertebral tendinitis as an abscess, because of the imaging features. The aim of this case series is to offer guidelines in the diagnosis of this rare disease to prevent unnecessary surgery. MATERIAL AND METHODS Six patients with already by imaging or retrospectively after surgery by pathologic report diagnosed prevertebral tendinitis were included in this study. None of these patients suffered from a chronically inflammatory disease. Three patients just received contrast enhanced computed tomography (CT) and another group of three patients received magnetic resonance imaging (MRI). In two out of three MRI examinations, we additionally performed diffusion weighted images and calculated the apparent diffusion coefficient (ADC) map. The laboratory reports obtained on the day of the computed tomography (CT) or magnetic resonance imaging (MRI) examinations were reviewed for C-reactive protein (CRP) and white blood cell count (WBCC). RESULTS All patients revealed a prevertebral cervical effusion. Five out of six patients showed amorphous calcifications in the tendon of the prevertebral muscles. In one case calcifications could not be identified at all because of very strong beam hardening artefacts caused by dental prothesis. The CRP values were increased in all patients (mean value 44.9 mg/l; SD ± 28.3). However, WBCC remained normal (mean value 8.4G/l; SD ± 2.7). Only for the two patients who received DWI it was possible to assess the quality of the prevertebral fluid accumulation and to detect the benign prevertebral effusion, which is typical for the retropharyngeal tendinitis. CONCLUSION According to the experience with our patients the best imaging feature is MRI with DWI and ADC map to reveal the benign prevertebral effusion and confirm the diagnosis of prevertebral tendinitis. In some cases MRI might not be available. Here we recommend CT scans to detect typical prevertebral calcifications. Especially a slight elevation of CRP and normal WBCC make the prevertebral tendinitis more likely.

MRI in paediatric hypoxic–ischemic disease, metabolic disorders and malformations—A review

MRI has become the most important modality in paediatric neuroimaging. It provides an excellent anatomical overview with good spatial and temporal resolution, allows investigations of the blood vessels, and - using technologies such as diffusion-weighted imaging and magnetic resonance spectroscopy - it allows quick and exact differentiation of ischemic, hypoxic, inflammatory, oncologic, traumatic and metabolic diseases. This review presents an overview of brain MRI in infants and children with suspected hypoxic-ischemic disease, metabolic disorders or (vascular) malformations, illustrating these issues by some MRI findings in selected important conditions and discussing some major clinical and pathophysiological aspects important for imaging.

Surface-Induced Phase of Tyrian Purple (6,6′-Dibromoindigo): Thin Film Formation and Stability

The appearance of surface-induced phases of molecular crystals is a frequently observed phenomenon in organic electronics. However, despite their fundamental importance, the origin of such phases is not yet fully resolved. The organic molecule 6,6′-dibromoindigo (Tyrian purple) forms two polymorphs within thin films. At growth temperatures of 150 °C, the well-known bulk structure forms, while at a substrate temperature of 50 °C, a surface-induced phase is observed instead. In the present work, the crystal structure of the surface-induced polymorph is solved by a combined experimental and theoretical approach using grazing incidence X-ray diffraction and molecular dynamics simulations. A comparison of both phases reveals that π–π stacking and hydrogen bonds are common motifs for the intermolecular packing. In-situ temperature studies reveal a phase transition from the surface-induced phase to the bulk phase at a temperature of 210 °C; the irreversibility of the transition indicates that the surface-induced phase is metastable. The crystallization behavior is investigated ex-situ starting from the sub-monolayer regime up to a nominal thickness of 9 nm using two different silicon oxide surfaces; island formation is observed together with a slight variation of the crystal structure. This work shows that surface-induced phases not only appear for compounds with weak, isotropic van der Waals bonds, but also for molecules exhibiting strong and highly directional hydrogen bonds.

Indexing of grazing-incidence X-ray diffraction patterns: the case of fibre-textured thin films

Crystal structure solutions from fibre-textured crystals within thin films are frequently achieved by grazing-incidence X-ray diffraction experiments. In the present work, analytical mathematical expressions are derived for the indexing of experimental diffraction patterns.

Indexation of grazing-incidence X-ray diffraction patterns

Crystal structure solution from thin films requires indexation of the diffraction pattern which means the assignment of Laue indices to the observed Bragg peaks. The focus of interest are molecular crystals at surfaces where usually low symmetry structures – either triclinic or monoclinic unit cells – are observed. The diffraction experiments for thin films are performed under grazing incidence condition of the primary x-ray beam which yields the reciprocal lattice vectors of the Bragg peaks split in two components: an in-plane part qxy and an out-ofplane part qz. Therefore, for this specific case two components of the reciprocal lattice vectors are available for the indexation process [1]. This is considerably different for the indexation procedure of single crystal diffraction pattern where all three components of the reciprocal lattice vectors are measured and powder diffraction on polycrystalline materials where only the lengths of the scattering vectors are detected. In a first step of our work analytical expressions were derived to calculate the lattice constants for a triclinic unit cell with the ab-plane parallel to the substrate Surface [2]. But in the general case the rotation matrix must be included which introduces additional unknown Parameters [3]. We use a mathematical formalism by including the specular diffraction peak so that the system of unknown parameters can be reduced from the 3to the 2-dimensional space. Thus in the first part of the indexation routine the lattice parameters a, b, gamma and the Laue indices h and k are determined followed by the second part calculating the residual parameters c, alpha, beta and the Laue index l. References: 1. D.-M. Smilgies, D.R. Blasini, J. Appl. Cryst. (2007), 40, 716-718. 2. M. Truger, O.M. Roscioni, C. Röthel, D. Kriegner, C. Simbrunner, R. Ahmed, E.D. Głowacki, J. Simbrunner, I. Salzmann, A.M. Coclite, A.O. Jones, R. Resel, Cryst Growth Des. (2016), 16, 3647-3655. 3. A. Moser, PhD Thesis, Graz University of Technology (2012).

Congenital hearing loss explained in adulthood. Computed tomography of the temporal bone in hemifacial microsomia. A case report.

We present a case of complex hemifacial microsomia (HFM) which was diagnosed at the age of 46 years. Imaging findings of a complex deformity of the temporal bone are presented and connected to a broad range of clinical symptoms. Computed tomography (CT) imaging indications are discussed briefly.