Virtual colon dissection with CT colonography compared with axial interpretation and conventional colonoscopy: preliminary results

OBJECTIVE: The aim of this study was to determine whether a new virtual colon dissection 3D visualization technique for CT colonography has a shorter analysis time and better sensitivity for detection of colonic polyps than interpretation of axial CT images. SUBJECTS AND METHODS. CT colonography was performed in 22 patients using 4-MDCT followed by conventional colonoscopy on the same day. The CT colonography data sets were analyzed by virtual colon dissection, which virtually bisects and unfolds the colon along its longitudinal axis to inspect the inner colonic surface for polyps. The same CT data sets were independently evaluated using axial interpretation. All data sets were independently interpreted by two radiologists in a blinded manner. RESULTS: Conventional colonoscopy revealed 31 colonic lesions in 20 patients. Twenty two of the lesions were smaller than 10 mm; nine were 10 mm or larger. Two of the original 22 patients were excluded, one because of residual stool and fluid and the other because of an impassable stenosing rectal wall cancer. For virtual colon dissection, the per-lesion sensitivity was 42% for observer 1 and 68% for observer 2; for axial interpretation, the respective sensitivities were 48% and 61%. For polyps 10 mm or larger, the respective sensitivities were 67% and 89% for virtual colon dissection and 89% and 100% for axial interpretation. The average time for reconstruction and analysis of virtual colon dissection was 36.8 min versus 29.2 min for axial images. Virtual colon dissection was feasible in both the supine and the prone positions in 45.5% of colonic segments, in either the supine or the prone position in 24.5%, and in neither position in 30% of segments. CONCLUSION: Although virtual colon dissection may facilitate detection of colonic polyps in isolated cases, its detection rate is not superior to axial interpretation, which is mainly attributable to failed rendering of insufficiently distended colonic segments or regions with residual feces. Virtual colon dissection is also the more time-consuming of the two procedures. With further improvement of path-finding and image segmentation, however, virtual colon dissection has the potential to be a useful interpretation tool for CT colonography.     

Anterior cruciate reconstruction combined with autologous osteochondral transplantation

The purpose of this prospective study was to evaluate the results of simultaneous anterior cruciate ligament (ACL) reconstruction and osteochondral autograft transplantation performed in patients suffering an anterior instability associated with symptomatic full-thickness cartilage defects. Our clinical report includes the first 21 patients (six women, 15 men) who have been followed up for 32 months or longer. The average patient age was 29 years (range 22–44 years), and mean time from injury to the combined reconstructive surgery was 10 months (range 4–27 months). The cartilage defects had a mean area of 3.5 cm² (range 2.0–5.0 cm²). All patients were evaluated according to the IKDC, Lysholm and Tegner scoring scales by an independent observer. A visual analogue scale (VAS) reflecting patient pain was evaluated. Assessment using the IKDC knee scoring scale revealed 81% of the patients with a normal or nearly normal knee joint. There was a significant improvement in subjective discomfort, and the KT-1000 arthrometric evaluation showed a reduction of the ventral tibial translation (5.9 to 1.9 mm). All but two patients had returned to full activities without restriction and were asymptomatic. The results of this study suggest that symptomatic full-thickness articular cartilage defects associated with ACL instability can be effectively treated by performing ACL reconstruction and osteochondral autologous grafts in one procedure. However, only the years which follow will show the long-term outcome of the patients.     

Evaluation of a 16-MDCT scanner in an emergency department: initial clinical experience and workflow analysis

OBJECTIVE: MDCT is especially suited for emergency purposes because it allows rapid high-resolution scans of large areas, fast high-quality reformatting in every orientation, and 3D illustration of the data set. In a prospective study, we evaluated the reliability and workflow of a dedicated emergency department 16-MDCT scanner in the management of patients presenting to the emergency department. SUBJECTS AND METHODS: The use of a 16-MDCT scanner for 503 patients in the emergency department of a university clinic was evaluated. For reasons of workflow analysis, seven precise time intervals were recorded during the emergency examinations. A new setting for repositioning multiple-trauma patients after imaging of the head and neck from the head-first position to the feet-first position was introduced. RESULTS: Six (1.2%) of the 503 patients were excluded because of technical malfunction or patient noncompliance. Image quality in the remaining 497 cases, including CT angiography and CT of multiple-trauma patients, was outstanding. Positioning of the patients took from 3 to 13 min depending on the body region examined, representing 33-67% of the mean room time, which ranged from 8 to 21 min. In multiple-trauma patients, the initial positioning took a mean of 6 min and repositioning took 8 min, representing 19% and 26% of total room time, respectively. CONCLUSION: The use of a dedicated 16-MDCT scanner in the emergency department resulted in short examination times even for examinations of multiple body regions under emergency conditions. The introduced setting-repositioning of multiple-trauma patients-allowed high image quality to be maintained. The trade-off in multiple-trauma patients was prolonged room time because of patient repositioning.     

Percutaneous Vein Occlusion with Small Intestinal Submucosa: An Experimental Pilot Study in Swine and Sheep

Purpose The objective of this study was to investigate the feasibility, outcomes, and amount of small intestinal submucosa (SIS) material needed for embolization of jugular vein (JV) in a swine and sheep model. Our hypothesis was that SIS would cause vein occlusion. Materials and Methods The external JVs (EJV) in swine (n = 6) and JVs in sheep (n = 6) were occluded with SIS fan-folded compressed strips. After percutaneous puncture of the peripheral portion of the EJV or JV, a TIPS set was used to exit their lumen centrally through the skin. The SIS strips were delivered into the isolated venous segment with a pull-through technique via a 10-Fr sheath. Follow-up venograms were done immediately after placement and at the time of sacrifice at 1 or 3 months. Gross examinations focused on the EJV or JV and their surrounding structures. Specimens were evaluated by histology. Results SIS strip(s) placement was successful in all cases, with immediate vein occlusion seen in 23 of 24 veins (95.8%). All EJVs treated with two strips and all JVs treated with three or four strips remained closed on 1- and 3-month follow-up venograms. Two EJVs treated with one strip and one JV treated with two strips were partially patent on venograms at 1 and 3 months. There has been one skin inflammatory reaction. Necropsies revealed excluded EJV or JV segments with SIS incorporation into the vein wall. Histology demonstrated various stages of SIS remodeling with fibrocytes, fibroblasts, endothelial cells, capillaries, and inflammatory cells. Conclusion We conclude that EJV and JV ablation with SIS strips using percutaneous exit catheterization is feasible and effective in animal models. Further exploration of SIS as vein ablation material is recommended.     

Assessment of inflammation in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia

Purpose  

Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a myocardial disease that predominantly affects the right ventricle (RV). Its hallmark feature is fibro-fatty replacement of RV myocardium. However, patchy inflammatory infiltrates in the RV are also consistently reported using autopsy and myocardial biopsy. Although the role of inflammation in ARVC/D is unresolved, the ability to assess inflammation non-invasively may aid in the diagnostic process. We aimed to establish whether cardiac inflammation can be assessed non-invasively in ARVC/D patients.     

Alternate or additional findings to stone disease on unenhanced computerized tomography for acute flank pain can impact management

PURPOSE: We evaluated the incidence and clinical relevance of alternate or additional findings on unenhanced CT in patients with acute flank pain and suspected urinary calculi. MATERIALS AND METHODS: A consecutive series of 1,500 patients underwent unenhanced CT due to acute flank pain. The absence or presence of urinary tract calculi and their localization were recorded. Alternate or additional CT findings were classified according to whether they required immediate or deferred treatment, or were of little or no clinical importance. RESULTS: Of the 1,500 patients 1,035 (69%) had urinary tract calculi, including 309 (30%) with nephrolithiasis, 377 (36%) with ureterolithiasis and 349 (34%) with the 2 conditions. Urolithiasis alone was found in 331 of these patients (32%) and additional pathological conditions were noted in 704 (68%). Of all patients 1,064 (71%) had other or additional CT findings. Of all patients 207 (14%) had nonstone related CT findings requiring immediate or deferred treatment, 464 (31%) had pathological conditions of little clinical importance and 393 (26%) had pathological conditions of no clinical relevance. CT was normal in 105 of all patients (7%). CONCLUSIONS: Unenhanced CT in patients with acute flank pain allows the accurate diagnosis of urinary stone disease and it can also provide further important information leading to emergency or deferred treatment in a substantial number of patients.     

The faster the better: anastomosis time influences patient survival after deceased donor kidney transplantation

Despite a continuously growing knowledge of the impact of factors on kidney graft function, such as donor age, body mass index, and cold ischemia time, few data are available regarding anastomosis time (AT) and its impact on long‐term results. We investigated whether surgical AT correlates with patient and graft survival after kidney transplantation performing a retrospective analysis of 1245 consecutive deceased donor kidney transplantations between 01/2000 and 12/2010 at Innsbruck Medical University. Kaplan–Meier and log‐rank analyses were carried out for 1‐ and 5‐year patient and graft survival. AT was defined as time from anastomosis start until reperfusion. Median AT was 30 min. Five‐year survival of allografts with an AT >30 min was 76.6% compared with 80.6% in the group with AT <30 min (P = 0.027). Patient survival in the group with higher AT similarly was inferior with 85.7% after 5 years compared with 89.6% (P < 0.0001) [Correction added on February 18, 2015, after first online publication: the percentage value for patient survival was previously incorrect and have now been changed to 89.6%]. Cox regression analysis revealed AT as an independent significant factor for patient survival (HR 1.021 per minute; 95% CI 1.006–1.037; P = 0.006). As longer AT closely correlates with inferior long‐term patient survival, it has to be considered as a major risk factor for inferior long‐term results after deceased donor kidney transplantation.     

Animal neuropsychology: validation of the Intra-Dimensional Extra-Dimensional set shifting task for mice

Research in animal neuropsychology is providing an exciting new generation of behavioral tests for mice that promise to overcome many of the limitations of current high-throughput testing, and provide direct animal homologues of clinically important measures in human research. Set shifting tasks are some of the best understood and widely used human neuropsychological tasks, with clinical relevance to traumatic brain injury, schizophrenia, autism, obsessive compulsive disorder, trichotillomania, and many other disorders. Here we report the first successful modification of a human set shifting neuropsychological task, the Intra-Dimensional Extra-Dimensional (IDED) task, for use with mice. We presented mice with a series of compound discrimination and reversal tasks where one stimulus dimension consistently cued reward. Task performance improved with a new set of compound stimuli, as did reversal performance--indicating the formation of a cognitive-attentional set. We then overtrained a subset of the mice, and presented control and overtrained mice with a new compound discrimination where a novel stimulus dimension cued reward. As is the case in human control subjects, control mice persisted in responding to the now-incorrect stimulus dimension, performing poorly on this extra-dimensional shift compared with the previous intra-dimensional shift, thereby validating the task as a measure of set shifting. Furthermore, overtrained mice were impaired on this extra-dimensional shift compared with controls, further validating the task. The advantages and disadvantages of the IDED task compared to high-throughput approaches are discussed.     

Ex vivo treatment of proliferating human cord blood stem cells with stroma-derived factor-1 enhances their ability to engraft NOD/SCID mice

Ex vivo proliferation of hematopoietic stem cells (HSCs) is important for cellular and gene therapy but is limited by the observation that HSCs do not engraft as they transit S/G(2)/M. Recently identified candidate inhibitors of human HSC cycling are transforming growth factor-beta(1) (TGF-beta(1)) and stroma-derived factor-1 (SDF-1). To determine the ability of these factors to alter the transplantability of human HSCs proliferating in vitro, lin(-) cord blood cells were first cultured for 96 hours in serum-free medium containing Flt3 ligand, Steel factor, interleukin-3, interleukin-6, and granulocyte colony-stimulating factor. These cells were then transferred to medium containing Steel factor and thrombopoietin with or without SDF-1 and/or TGF-beta(1) for 48 hours. Exposure to SDF-1 but not TGF-beta(1) significantly increased (> 2-fold) the recovery of HSCs able to repopulate nonobese diabetic/severe combined immunodeficiency mice. These results suggest new strategies for improving the engraftment activity of HSCs stimulated to proliferate ex vivo.