Essential features of Chiari II malformation in MR imaging: an interobserver reliability study—part 1

Item does not contain fulltextPURPOSE: Brain MR imaging is essential in the assessment of Chiari II malformation in clinical and research settings concerning spina bifida. However, the interpretation of morphological features of the malformation on MR images may not always be straightforward. In an attempt to select those features that unambiguously characterize the Chiari II malformation, we investigated the interobserver reliability of all its well-known MR features. METHODS: Brain MR images of 79 children [26 presumed to have Chiari II malformation, 36 presumed to have no cerebral abnormalities, and 17 children in whom some Chiari II malformation features might be present; mean age 10.6 (SD 3.2; range, 6-16) years] were blindly and independently reviewed by three observers. They rated 33 morphological features of the Chiari II malformation as present, absent, or indefinable in three planes (sagittal, axial, and coronal). The interobserver reliability was assessed using kappa statistics. RESULTS: Twenty-three of the features studied turned out to be unreliable, whereas the interobserver agreement was almost perfect (kappa value > 0.8) for nine features (eight in the sagittal plane and one in the axial plane, but none in the coronal plane). CONCLUSIONS: This study presents essential features of the Chiari II malformation on MR images by ruling out the unreliable features. Using these features may improve the assessment of Chiari II malformation in clinical and research settings.1 juli 201

External validation of a model to predict the survival of patients presenting with a spinal epidural metastasis

The surgical treatment of spinal metastases is evolving. The major problem is the selection of patients who may benefit from surgical treatment. One of the criteria is an expected survival of at least 3 months. A prediction model has been previously developed. The present study has been performed in order to validate externally the model and to demonstrate that this model can be generalized to other institutions and other countries than the Netherlands. Data of 356 patients from five centers in Germany, Spain, Sweden, and the Netherlands who were treated for metastatic epidural spinal cord compression were collected. Hazard ratios in the test population corresponded with those of the developmental population. However, the observed and the expected survival were different. Analysis revealed that the baseline hazard function was significantly different. This tempted us to combine the data and develop a new prediction model. Estimating iteratively, a baseline hazard was composed. An adapted prediction model is presented. External validation of a prediction model revealed a difference in expected survival, although the relative contribution of the specific hazard ratios was the same as in the developmental population. This study emphasized the need to check the baseline hazard function in external validation. A new model has been developed using an estimated baseline hazar

Interobserver reliability and diagnostic performance of Chiari II malformation measures in MR imaging—part 2

PURPOSE: Brain MR imaging is essential in the assessment of Chiari II malformation in clinical and research settings concerning spina bifida. However, the interpretation of MR images of the malformation is not always straightforward. Morphometric analyses of the extent of Chiari II malformation may improve the assessment. In an attempt to select appropriate morphometric measures for this purpose, we investigated the interobserver reliability and diagnostic performance of several morphometric measures of Chiari II malformation on MR images. METHODS: Brain MR images of 79 children [26 with open spinal dysraphism, 17 with closed spinal dysraphism, and 36 without spinal dysraphism; mean age 10.6 (SD 3.2; range, 6-16) years] were evaluated. All children had been assessed for Chiari II malformation (defined as cerebellar herniation in combination with open spinal dysraphism; n = 23). Three observers blindly and independently reviewed the MR images for 21 measures of the cerebellum, brainstem, and posterior fossa in three planes. The interobserver reliability was assessed by an agreement index (AI = 1 - RRE) and the diagnostic performance by receiver operating characteristic analyses. RESULTS: Reliability was good for most measures, except for the degree of herniation of the vermis and tonsil. Most values differed statistically significantly between children with and without Chiari II malformation. The measures mamillopontine distance and cerebellar width showed excellent diagnostic performance. CONCLUSIONS: Morphometric measures may reliably quantify the morphological distortions of Chiari II malformation on MR images and provide additional tools to assess the severity of Chiari II malformation in clinical and research settings

Intestinal Damage Determines the Inflammatory Response and Early Complications in Patients Receiving Conditioning for a Stem Cell Transplantation

Contains fulltext : 87954.pdf (publisher's version ) (Open Access)BACKGROUND: Stem cell transplantation (SCT) is still complicated by the occurrence of fever and inflammatory complications attributed to neutropenia and subsequent infectious complications. The role of mucosal barrier injury (MBI) of the intestinal tract therein has received little attention. METHODS: We performed a retrospective analysis in 163 SCT recipients of which data had been collected prospectively on intestinal damage (citrulline), inflammation (C-reactive protein), and neutrophil count. Six different conditioning regimens were studied; 5 myeloablative (MA) and 1 non-myeloablative (NMA). Linear mixed model multivariate and AUC analyses were used to define the role of intestinal damage in post-SCT inflammation. We also studied the relationship between the degree of intestinal damage and the occurrence of early post-SCT complications. RESULTS: In the 5 MA regimen there was a striking pattern of inflammatory response that coincided with the occurrence of severe intestinal damage. This contrasted with a modest inflammatory response seen in the NMA regimen in which intestinal damage was limited. With linear mixed model analysis the degree of intestinal damage was shown the most important determinant of the inflammatory response, and both neutropenia and bacteremia had only a minor impact. AUC analysis revealed a strong correlation between citrulline and CRP (Pearson correlation r = 0.96). Intestinal damage was associated with the occurrence of bacteremia and acute lung injury, and influenced the kinetics of acute graft-versus-host disease. CONCLUSION: The degree of intestinal damage after myeloablative conditioning appeared to be the most important determined the inflammatory response following SCT, and was associated with inflammatory complications. Studies should explore ways to ameliorate cytotoxic therapy-induced intestinal damage in order to reduce complications associated with myeloablative conditioning therapy

Subsidence of Stand-alone Cervical Carbon Fiber Cages

AbstractOBJECTIVE:To investigate the number of subsidences of inserted cervical carbon fiber cages and to define predictive factors for subsidence.METHODS:All patients treated for a cervical herniated disc and fusion with a cervical carbon fiber cage between January 2002 and December 2003 were retrospectively identified. The radiological examinations were reviewed, and, especially, the presence of subsidence was noted. Possible predictive factors for subsidence were determined before the investigation.RESULTS:In 69 patients, there were 96 cages inserted, of which 29.2% subsided. Of all factors investigated, only smoking seemed to be predictive for subsidence, whereas insertion at C6 to C7 clearly had a higher risk at subsidence. Subsidence was not related to outcome or fusion.CONCLUSION:Although the high number of subsidence of cages has never been described before, clinical outcome and fusion rate is comparable with the literature.</jats:sec

No Impact of Dectin-1 Polymorphism Y238X On the Outcome of Hematopoietic Stem Cell Transplantation, but a Role for Candida in Acute Graft-Versus-Host Disease.

Abstract Abstract 4498 Dectin-1 is a C-type lectin receptor that recognizes b-1,3-glucan, and plays an important role in antifungal immunity. The recently discovered dectin-1 Y238X polymorphism, which results in “loss-of-function” has been shown associated with increased Candida colonization of stem cell transplantation (SCT) recipients. Besides its role in antifungal immunity Dectin-1 exhibits a broader function in immunity. Stimulation of Dectin-1 with β-glucan affects antigen presentation, modulates T-lymphocytic (CD4+, both Th1 and Th17, and CD8+) and B-lymphocytic responses, and induces cytokine production including interleukin (IL) 10, IL-12 and IL-23. These specific T-cell responses and cytokines are of particular interest in SCT because they are involved in graft-versus-leukemia (GvL) effects as well as in the pathogenesis of graft-versus-host disease (GvHD). Therefore we now performed a retrospective study in 140 patients on the impact of the Y238X polymorphism on the outcome of myeloablative T cell-depleted matched related SCT. The allele frequency of the Y238X polymorphism was 6.6%, with 10.7% of patients and 15.7% of donors bearing the polymorphism. All were heterozygous and at least one polymorphism was present in 28 of 140 (20%) patient-donor pairs. We found no impact of the polymorphism on the occurrence of acute and chronic GvHD, non-relapse and relapse related mortality, nor disease-free and overall survival. Interestingly, patients from patient-donor pairs bearing the wild-type allele who were colonized with Candida had an increased incidence of acute GvHD compared to non-colonized patients (41.9% vs. 20.4%, OR=2.6 95%CI:1.02-6.58, P=0.04). However, this seemed to be the other way round for patients from pairs with the Y238X polymorphism (23.5% colonized vs. 30% not colonized, OR=0.7, ns). Therefore we hypothesize that the loss-of-function of dectin-1 increases colonization through deficient mucosal immunity, but prevents inflammatory complications resulting from colonization (Figure 1). This might explain the lack of an effect of the Dectin-1 Y238X polymorphism on outcome measures of SCT. Figure 1: Simplified hypothesis on the role of dectin-1, polymorphism Y238X, and Candida colonization on acute GvHD and possibly GvL. Figure 1:. Simplified hypothesis on the role of dectin-1, polymorphism Y238X, and Candida colonization on acute GvHD and possibly GvL. In case of Candida colonization (left) activation of the dectin-1 receptor influences immune responses and allo-reactivity increasing the incidence of acute GvHD. In the presence of the loss-of-function polymorphism Y238X (right), although Candida colonization is increased, due to the loss-of-function of dectin-1, no changes in the allo-reactive T-cell responses occur. Disclosures: No relevant conflicts of interest to declare. </jats:sec