Incompatibility of contrast agents with intravascular medications. Work in progress

In vitro and in vivo precipitation of iodinated contrast agents when ioxaglate and papaverine are given together has been reported. To verify these reports and to investigate other medications not previously tested, the authors analyzed mixtures of contrast agents and medications in vitro with a light spectrophotometer and observed them for visible precipitates for up to 120 minutes. Previously reported incompatibilities between ionic or low-osmolality contrast media and medications were verified, and several new incompatibilities were discovered. No incompatibilities were found when the drugs tested were mixed with the new nonionic contrast media.     

Chlamydial etiology of acute lower respiratory tract infections in children in the Sudan

The role of Chlamydia pneumoniae in 110 Sudanese children with signs of acute lower respiratory tract infections (ALRI) was investigated. Four (3.6%) had evidence of C. pneumoniae infection, of whom 3 were culture-positive, while 1 had an antibody response suggesting a recent infection. IgG antibodies at a titer of ≥1:32 to C. pneumoniae, Chlamydia psittaci and Chlamydia trachomatis were detected in 27 (24.5%), 27 (24.5%) and 7 (6.4%) of the 110 ALRI cases, respectively. C. pneumoniae, C. trachomatis or C. psittaci were not detected in nasopharyngeal secretions from any of 110 patients when fluorescence-labeled specific monoclonal antibodies were used. In a seroepidemiological survey, 318 healthy Sudanese persons aged between 1 month and 67 years were studied for C. pneumoniae antibodies.     

Sweet's syndrome—therapy with cyclosporin

We report the case of a 39-year-old female patient suffering from Sweet's syndrome after an upper respiratory tract infection. Cyclosporin A at a dose of 10 mg/kg per day was given as initial treatment. Skin lesions and general malaise resolved within 9 days. The cyclosporin dose was decreased within 21 days, without recurrence of the eruption. Cyclosporin is a potent inhibitor of T lymphocytes, but affects granulocyte and monocyte functions as well. Success of treatment in our case shows that cyclosporin represents an alternative to steroid treatment in patients with Sweet's syndrome.     

Time-resolved particle image velocimetry and laser doppler anemometry study of the turbulent flow field of bileaflet mechanical mitral prostheses

Dynamic particle image velocimetry (PIV) was applied to the study of the flow field associated with prosthetic heart valves. The results were compared with those of laser Doppler anemometry (LDA). Anatomically and antianatomically oriented Jyros (JR) and St. Jude Medical (SJM) valves were compared in the mitral position to study the effects of valve design on the downstream flow field. The experimental program used a dynamic PIV system utilizing high-speed, high-resolution video to map the true time-resolved velocity field inside the simulated ventricle. This system was complemented by a study using the more traditional LDA system for comparison. Based on the experimental data, the following general conclusions can be made. High-resolution dynamic PIV can capture true chronological changes in the velocity and turbulence fields. It also produces very detailed velocity and turbulence information comparable to the LDA results. In the vertical measuring plane that passes both the center of the aortic and mitral valves (A-A section), the two valves (the SJM and the JR) show distinct circulatory flow patterns when the valve is installed in the antianatomical orientation. Small differences in valve design can generate noticeable differences, particularly during the accelerating flow phase. The SJM valve maintains a relatively high velocity through the central orifice; the curved leaflets of the JR valve generate higher velocities with a divergent flow during the accelerating and peak flow phases. In the velocity field directly below the mitral valve and normal to the previous measuring plane (B-B section), where characteristic differences in valve design will be visible, symmetrical twin circulations were observed because of the divergent nature of the flow generated by the two inclined half-disks installed in the antianatomical orientation. The SJM valve, with a central downward flow near the valve, is contrasted with the JR valve, which has a peripheral downward circulation with higher, turbulent stresses.     

Validation of the National Institute of Neurological Disorders and Stroke Spinal Cord Injury MRI Common Data Elements Instrument

BACKGROUND AND PURPOSE:The National Institute of Neurological Disorders and Stroke common data elements initiative was created to provide a consistent method for recording and reporting observations related to neurologic diseases in clinical trials. The purpose of this study is to validate the subset of common data elements related to MR imaging evaluation of acute spinal cord injury.MATERIALS AND METHODS:Thirty-five cervical and thoracic MR imaging studies of patients with acute spinal cord injury were evaluated independently in 2 rounds by 5 expert reviewers. Intra- and interrater agreement were calculated for 17 distinct MR imaging observations related to spinal cord injury. These included ordinal, categoric, and continuous measures related to the length and location of spinal cord hemorrhage and edema as well as spinal canal and cord measurements. Level of agreement was calculated using the interclass correlation coefficient and kappa.RESULTS:The ordinal common data elements spinal cord injury elements for lesion center and rostral or caudal extent of edema or hemorrhage demonstrated agreement ranging from interclass correlation coefficient 0.68 to 0.99. Reproducibility ranged from 0.95 to 1.00. Moderate agreement was observed for absolute length of hemorrhage and edema (0.54 to 0.60) with good reproducibility (0.78 to 0.83). Agreement for the Brain and Spinal Injury Center score showed the lowest interrater agreement with an overall kappa of 0.27 (0.20, 0.34). For 7 of the 8 variables related to spinal cord injury, agreement improved between the first and second evaluation. Continuous diameter measures of the spinal cord and spinal canal using interclass correlation coefficient varied substantially (0.23 to 0.83).CONCLUSIONS:Agreement was more consistent for the ordinal measures of spinal cord injury than continuous measures. Good to excellent agreement on length and location of spinal cord hemorrhage and edema can be achieved with ordinal measures alone.

In 2006, the National Institute of Neurological Disorders and Stroke (NINDS) began a process to develop common data elements (CDEs) to provide a standardized method for the collection of clinical data related to neurologic diseases.^1-3 Recognizing that there is a lack of clear and consistent terminology for spine disorders, particularly spinal cord injury (SCI), in 2014, the NINDS convened a workgroup comprising expert stakeholders for the development of SCI CDE instruments that included clinical care assessments and imaging.^3-8 This new set of SCI CDE instruments aimed to increase the efficiency and value of clinical research studies and treatment, increase data quality, facilitate data sharing, and help educate new clinical investigators.³ Investigators are expected to incorporate the CDE modules in grant applications and National Institutes of Health–funded research.The MR imaging SCI CDE subset was created to be a comprehensive and standardized terminology for describing MR imaging findings in patients with SCI. This collection consists of a case report form (CRF) containing 35 discrete measures and responses divided into 4 main categories: general imaging characteristics, spinal injury features, canal and cord measurements, and chronic SCI features. The responses are of 3 types: Boolean, categoric, and an ordinal range representing specific anatomic locations. These measures were chosen to represent both objective and subjective assessment derived from routine clinical MR images. The workgroup codified these features using existing CDEs that have proved value in the published literature, and when ones did not exist, the workgroup developed the feature and the response parameters.As with the development of any CRF used for a clinical trial or research, the goal is to provide an instrument that provides useful data representations that are reproducible across trained observers and institutions, require minimal cognitive effort, minimize ambiguity, and are both accurate and precise. Reproducibility of the observations through rigorous testing by multiple observers is a needed step to validate the instrument before clinical or research use. However, the evaluation process may not entirely reproduce the clinical environment in which it is meant to be used such that datasets and observers are overly prepared or optimized. Therefore, the goal of this study is to determine the inter- and intrarater reliability of the NINDS MR imaging CDEs when assessed by MR imaging experts with familiarity with SCI. We hypothesize that there will be good to excellent agreement (kappa >0.4) among the expert raters after limited training.