Dimers or trimers? A characterization of the halogen bonded complexes of CFX (X=I or Br) with dimethyl ether and acetone in cryosolutions.

Acetone molecules dissolved in liquid krypton are inclined to self-associate into dimers. This behavior affects its use as a prototype Lewis base in studies of weak intermolecular interactions. In this study infrared spectra of mixed solutions of dimethyl ether and CFX and of acetone and CFX (with X=I or Br) dissolved in liquid argon and liquid krypton are recorded at constant temperature.

Self-Associating Behavior of Acetone in Liquid Krypton.

Acetone molecules are inclined to self-associate through dipole-dipole interactions because of their large dipole moment. Infrared spectroscopy of compounds dissolved in liquid noble gases supported by high level ab initio calculations allows investigating the self-associating behavior and determining the thermodynamical properties. In this study, infrared spectra of various concentrations of acetone dissolved in liquid krypton are recorded at constant temperature.

Exploring the limits of cryospectroscopy: Least-squares based approaches for analyzing the self-association of HCl.

To rationalize the concentration dependent behavior observed for a large spectral data set of HCl recorded in liquid argon, least-squares based numerical methods are developed and validated. In these methods, for each wavenumber a polynomial is used to mimic the relation between monomer concentrations and measured absorbances. Least-squares fitting of higher degree polynomials tends to overfit and thus leads to compensation effects where a contribution due to one species is compensated for by a negative contribution of another.

Direct comparison of conventional radiography and cone-beam CT in small bone and joint trauma.

Objective: To compare the diagnostic value of cone-beam computed tomography (CBCT) and conventional radiography (CR) after acute small bone or joint trauma.

Materials And Methods: Between March 2013 and January 2014, 231 patients with recent small bone or joint trauma underwent CR and subsequent CBCT. CR and CBCT examinations were independently assessed by two readers, blinded to the result of the other modality.

Atraumatic bilateral scapular spine fracture several months after bilateral reverse total shoulder arthroplasty.

We report an 89-year-old woman with bilateral atraumatic scapular spine fracture several months after bilateral reverse total shoulder arthroplasty (RTSA). Recently, RTSA has gained popularity in the surgical treatment of complex shoulder disorders such as cuff tear arthropathy. However, scapular fractures may occur several months after surgery as a late complication of this procedure.

Middle ear cholesteatoma: non-echo-planar diffusion-weighted MR imaging versus delayed gadolinium-enhanced T1-weighted MR imaging--value in detection.

Purpose: To retrospectively compare non-echo-planar (non-EP) diffusion-weighted (DW) imaging, delayed gadolinium-enhanced T1-weighted magnetic resonance (MR) imaging, and the combination of both techniques in the evaluation of patients with cholesteatoma.

Materials And Methods: This institutional review board-approved study, for which the need to obtain informed consent was waived, included 57 patients clinically suspected of having a middle ear cholesteatoma without a history of surgery and 63 patients imaged before "second-look" surgery. Four blinded radiologists evaluated three sets of MR images: a set of delayed gadolinium-enhanced T1-weighted images, a set of non-EP DW images, and a set of both kinds of images.

Lymphadenopathy at the medial epitrochlear region in cat-scratch disease.

Our objective was to describe the imaging features of lymphadenopathy at the medial epitrochlear region as frequently seen in cat-scratch disease (CSD) and to compare these features with those seen in non-CSD. Ten patients (four males and six females) presented with a subcutaneous soft tissue mass at the medial epitrochlear region. Three patients were younger than 15 years.

Reliability of measuring volume by different methods for tumors of the musculoskeletal system.

In the present study different methods for determining the volume of a tumor were evaluated. For 12 models, the real volume, the volume according to measurement of the surface area on MRI, an ellipsoid and a cylindrical approximation of the volume, as well as the maximum diameter, were determined. There appeared to be a good correlation between all calculated volumes and the real volume.

Thyroid acropachy: correlation of imaging and pathology.

Thyroid acropachy is a rare manifestation of autoimmune thyroid disease, in the form of soft tissue swelling of the hands and feet with insidious onset, associated with clubbing and characteristic periosteal reactions. It is usually part of a syndrome consisting of a typical triad of thyroid acropachy, exophthalmos, and pretibial myxedema. The purpose of this case report is to demonstrate the imaging features of this typical triad in a 65-year-old-woman.

Low-grade chondrosarcoma vs enchondroma: challenges in diagnosis and management.

A 28-year-old man presented with a swelling at the right thoracic wall. Computed tomography showed an aggressive process involving the cortex of the rib with concomitant soft tissue mass. However, a needle biopsy specimen revealed an enchondroma and consequently the physician decided to apply a "wait-and-see" strategy.

Imaging of Soft Tissue Tumors in the Pediatric Patient.

The presence of a soft tissue mass in children is of concern to parents and physicians. Fortunately, these masses are rare and usually benign or pseudotumoral. When dealing with malignant soft tissue tumors, therapeutic options and long-term survival are strongly related to the disease stage at the time of diagnosis.

MR features of peripheral nerve sheath tumors: can a calculated index compete with radiologist's experience?

The aims of this study were, firstly, to provide a formula (neurogenic index) based on MR characteristics used in daily routine for predicting whether a soft tissue tumor is neurogenic or not, secondly, to test prospectively the performance of this formula, and thirdly, to compare this performance with that of radiologists experienced in MR imaging of soft tissue tumors. Retrospectively, MR images of 70 neurogenic and 70 non-neurogenic soft tissue tumors were evaluated in random order by two teams of two observers each. A neurogenic index (NI) was calculated based on those MR parameters that showed no or minor interobserver variability.

Metachronous eosinophilic granuloma of bone.

We present the case of a 4-year-old girl who developed a metachronous osseous lesion of the left distal femur five months after successful surgical treatment of an eosinophilic granuloma in the left proximal femur. After treatment of the second lesion with curettage, no further recurrence occurred during a follow-up interval of 17 months. Radiologists should be aware that additional eosinophilic granulomas of bone, occurring in up to four years after the initial diagnosis, should still be interpreted as a localized form of Langerhans'cell histiocytosis with a more favorable prognosis than the multifocal disseminated form, with involvement of organ systems other than the skeletal system.

Sclerosing bone dysplasias: genetic and radioclinical features.

Although knowledge of basic genetics in the field of sclerosing bone dysplasias is progressing, the radiologist still plays a pivotal role in the diagnosis of this relatively poorly understood group of disorders. Based on a target site approach, these anomalies are classified into three groups. Within each group, further differentiation can be made by distinctive clinical findings and by mode of inheritance: (a) dysplasias of endochondral bone formation: osteopetrosis (Albers-Schönberg disease), pycnodysostosis, enostosis, osteopoikilosis, osteopathia striata (Voorhoeve disease); (b) dysplasias of intramembranous bone formation: progressive diaphyseal dysplasia (Camurati-Engelmann disease) and variants, hyperostosis corticalis generalisata (Van Buchem disease) and variants; and (c) mixed sclerosing dysplasias: melorheostosis (Leri disease) and overlap syndromes.

MR imaging of clear cell sarcoma (malignant melanoma of the soft parts): a multicenter correlative MRI-pathology study of 21 cases and literature review.

Objective: To evaluate MR imaging and pathology findings in order to define the characteristic features of clear cell sarcoma of the soft tissues (malignant melanoma of the soft parts).

Design And Patients: MR examinations of 21 patients with histologically proven clear cell sarcoma of the musculoskeletal system were retrospectively reviewed and assessed for shape, homogeneity, delineation, signal intensities on T1- and T2-weighted images, contrast enhancement, relationship with adjacent fascia or tendon, secondary bone involvement, and intratumoral necrosis. In 19 cases the pathology findings were available for review and for a comparative MR-pathology study.

[Magnetic resonance imaging of soft tissue tumors of the hand and wrist].

We will discuss the imaging characteristics of soft tissue tumors of the hand and wrist, especially the magnetic resonance imaging findings, since MRI has proven to be the gold standard for characterization of soft tissue tumors. Our series consists of 71 tumors of the hand and wrist, that were examined by magnetic resonance imaging. Fourty-four lesions were benign, 7 malignant, and 20 lesions were pseudotumoral masses.

Desmoplastic fibroma of bone: MRI features.

Desmoplastic fibroma of bone is a very rare benign tumor, which may be locally aggressive. In contrast to the well-documented radiological appearance, the literature on MR imaging features of this tumor is scarce. The MR imaging characteristics in our case are compared to those previously reported.

Proteus syndrome: MRI characteristics of plantar cerebriform hyperplasia.

Proteus syndrome is a rare congenital hamartomatous syndrome with a variety of abnormalities. It shares many features with other congenital hamartomatous disorders, but cerebriform hyperplasia of the soles and the palms is known as a quite distinctive characteristic in the dermatologic literature. The purpose of this case report is to demonstrate the MRI features of plantar cerebriform hyperplasia in a 9-year-old boy with known Proteus syndrome.