Neural network algorithm for detection of erosions and ankylosis on CT of the sacroiliac joints: multicentre development and validation of diagnostic accuracy

OBJECTIVES

To evaluate the feasibility and diagnostic accuracy of a deep learning network for detection of structural lesions of sacroiliitis on multicentre pelvic CT scans.

METHODS

Pelvic CT scans of 145 patients (81 female, 121 Ghent University/24 Alberta University, 18-87 years old, mean 40 ± 13 years, 2005-2021) with a clinical suspicion of sacroiliitis were retrospectively included. After manual sacroiliac joint (SIJ) segmentation and structural lesion annotation, a U-Net for SIJ segmentation and two separate convolutional neural networks (CNN) for erosion and ankylosis detection were trained. In-training validation and tenfold validation testing (U-Net-n = 10 × 58; CNN-n = 10 × 29) on a test dataset were performed to assess performance on a slice-by-slice and patient level (dice coefficient/accuracy/sensitivity/specificity/positive and negative predictive value/ROC AUC). Patient-level optimisation was applied to increase the performance regarding predefined statistical metrics. Gradient-weighted class activation mapping (Grad-CAM++) heatmap explainability analysis highlighted image parts with statistically important regions for algorithmic decisions.

RESULTS

Regarding SIJ segmentation, a dice coefficient of 0.75 was obtained in the test dataset. For slice-by-slice structural lesion detection, a sensitivity/specificity/ROC AUC of 95%/89%/0.92 and 93%/91%/0.91 were obtained in the test dataset for erosion and ankylosis detection, respectively. For patient-level lesion detection after pipeline optimisation for predefined statistical metrics, a sensitivity/specificity of 95%/85% and 82%/97% were obtained for erosion and ankylosis detection, respectively. Grad-CAM++  explainability analysis highlighted cortical edges as focus for pipeline decisions.

CONCLUSIONS

An optimised deep learning pipeline, including an explainability analysis, detects structural lesions of sacroiliitis on pelvic CT scans with excellent statistical performance on a slice-by-slice and patient level.

CLINICAL RELEVANCE STATEMENT

An optimised deep learning pipeline, including a robust explainability analysis, detects structural lesions of sacroiliitis on pelvic CT scans with excellent statistical metrics on a slice-by-slice and patient level.

KEY POINTS

• Structural lesions of sacroiliitis can be detected automatically in pelvic CT scans. • Both automatic segmentation and disease detection yield excellent statistical outcome metrics. • The algorithm takes decisions based on cortical edges, rendering an explainable solution.

POS0989 DEVELOPMENT OF INTERNATIONAL CONSENSUS ON A STANDARDIZED IMAGE ACQUISITION PROTOCOL FOR DIAGNOSTIC EVALUATION OF THE SACROILIAC JOINTS BY MRI – AN ASAS-SPARTAN COLLABORATION

Background

In 2009, ASAS published a ‘Definition of active sacroiliitis on MRI for classification of axial spondyloarthritis (axSpA)’. This definition relied on two MRI sequences to make this determination – semicoronal T1 and STIR. Since then, this approach has frequently been used for diagnosis, even though that was never the intent of the definition. In 2015, the European Society of Skeletal Radiology (ESSR) published its recommendations for an SIJ MRI image acquisition protocol (IAP) for diagnostic purposes that required 4 MRI sequences but there is still no IAP that has been widely accepted as a minimum standard worldwide. In 2020, an informal survey of 24 academic sites (12 Europe, 12 North America) confirmed that 24/24 sites performed a minimum of 3 MRI sequences for diagnosis (19 performed 4-8 sequences) because the 2-sequence protocol was considered inadequate.

Objectives

To develop the minimum requirements for a standardized IAP for MRI of the sacroiliac joints for diagnostic ascertainment of sacroiliitis.

Methods

All radiologist members of the ASAS and SPARTAN Classification in axSpA (CLASSIC) project, along with one European and one North American rheumatologist with extensive MRI experience in SpA clinical practice and research, were invited to participate in a consensus exercise. A draft IAP was circulated to all participants along with background information and justification for the draft proposal. Feedback on all issues was received by email, tabulated and recirculated. Participants were broadly in favour of the proposal and two months later a teleconference meeting took place and remaining points of contention were resolved. Examples of the proposed IAP performed on new, 10 and 22 years’ old MRI scanners were made available for review in DICOM format. Next the revised draft of the IAP was presented at the ASAS annual meeting to the entire membership on 14 January 2022, and voted on.

Results

A 4-sequence IAP, 3-semicoronal and 1-semiaxial, is recommended for diagnostic ascertainment of sacroiliitis and its differential diagnoses (Table 1). It must meet the following requirements: Semicoronal sequences should be parallel to the dorsal cortex of the S2 vertebral body, and include: 1) a sequence sensitive for the detection of active inflammation being T2-weighted with suppression of fat signal; 2) a sequence sensitive for the detection of structural damage in bone and bone marrow with T1-weighting; 3) a sequence that is designed to optimally depict the bone-cartilage interface of the articular surface and be sensitive for detection of bone erosion; plus 4) a semiaxial sequence sensitive for inflammation detection. The IAP was approved at the ASAS annual meeting by a vote of the entire membership with 91% in favour.

Table 1.

A standardized SIJ MRI Acquisition Protocol for diagnostic ascertainment of sacroiliitis

OrientationSequenceTarget Lesion(s)Semicoronal Parallel to the dorsal cortex of the S2 vertebral bodyT1-weighted Spin EchoStructural: Fat lesions, erosion, sclerosis, backfill, ankylosis.T2-weighted with suppressed fat signal (STIR, T2FS or equivalent)Inflammatory: Bone marrow edema (BME)T1-weighted with suppressed fat signal (2D or 3D T1FS)Structural: Erosion of the articular surfaceSemiaxial Perpendicular to semicoronalT2-weighted with suppressed fat signal (STIR, T2FS or equivalent)Inflammatory: Bone marrow edema (BME)

Conclusion

A standardized IAP for MRI of the sacroiliac joints for diagnostic ascertainment of sacroiliitis is recommended and should be comprised of a minimum of 4 sequences, in 2-planes, that will optimally visualize inflammation, structural damage, and the bone-cartilage interface.

Disclosure of Interests

Robert Lambert Paid instructor for: Novartis, Consultant of: Calyx, CARE Arthritis, Image Analysis Group, Xenofon Baraliakos Speakers bureau: Abbvie, Pfizer, MSD, UCB, Novartis, Lilly, Galapagos, Hexal, Paid instructor for: Abbvie, Pfizer, MSD, UCB, Novartis, Lilly, Galapagos, Hexal, Consultant of: Abbvie, Pfizer, MSD, UCB, Novartis, Lilly, Galapagos, Hexal, Grant/research support from: Abbvie, MSD, Novartis, Lilly, Stephanie Bernard Consultant of: Elsevier Amirsys, John Carrino Consultant of: Pfizer, Regeneron, Globus, Carestream, Image Analysis Group, Image Biopsy Lab, Torsten Diekhoff Speakers bureau: Novartis, MSD, Canon MS, Consultant of: Eli Lilly, Iris Eshed: None declared, Kay-Geert Hermann Speakers bureau: AbbVie, Pfizer, MSD, Novartis. Co-founder: BerlinFlame GmbH, Nele Herregods: None declared, Jacob L Jaremko: None declared, Lennart Jans: None declared, Anne Grethe Jurik: None declared, John O’Neill: None declared, Monique Reijnierse: None declared, Michael Tuite Consultant of: GE HealthCare, Walter P Maksymowych Speakers bureau: Abbvie, Janssen, Novartis, Pfizer, UCB, Consultant of: Abbvie, Boehringer Ingelheim, Celgene, Eli-Lilly, Galapagos, Novartis, Pfizer, UCB, Grant/research support from: Abbvie, Novartis, Pfizer, UCB

MRI in axial spondyloarthritis: understanding an 'ASAS-positive MRI' and the ASAS classification criteria

In 2009, the Assessment of SpondyloArthritis international Society (ASAS) published a definition of 'active sacroiliitis on magnetic resonance imaging (MRI) for classification of axial spondyloarthritis'. This new definition of an 'ASAS-positive MRI' was integral to new classification criteria for axial spondyloarthritis that were published in the same year. The ASAS MRI definition had the considerable advantage of simplicity and the definition gained popularity as guidance for interpreting MRI of the sacroiliac joints in clinical practice. However, classification criteria are not designed for use in clinical practice with the consequence that overreliance on the presence of bone marrow edema, which is the principal determinant of an 'ASAS-positive MRI', may result in a tendency to overcall inflammatory sacroiliitis in the clinical setting. This article aims to inform the reader about the rationale behind the ASAS definition of a positive MRI and ASAS classification criteria, their proper use in research and why they should not be used in clinical practice. The article also contains guidance for an updated imaging protocol and interpretation of images including typical imaging findings, differential diagnosis, and common pitfalls.

AB0594 IMPROVING OSTEOARTHRITIS CARE BY AUTOMATIC MEASUREMENT OF HIP EFFUSION USING AI

Background:

Osteoarthritis (OA) is the commonest disease affecting hip joints and has high prevalence across various age groups [1,2]. Effusion is a hallmark of OA and could represent a potential target for therapy [3–5]. Positive correlations of effusion to clinical outcomes are not well established, partly due to variability in manual assessment. Voxel-based volume quantification could reduce this variability [6].

Objectives:

We examine the inter-observer agreement of manual assessment of voxel-based effusion volume from coronal STIR MRI sequences at two time points and examine the feasibility of using Artificial Intelligence (AI) for standalone volume assessment.

Methods:

Our algorithm is based on Mask R-CNN [7] and was trained on labeled effusion regions in MRI slices from 68 patients with hip osteoarthritis. For validation, 2 human readers measured effusion from MRI STIR sequences of 25 patients at baseline and at 8 weeks follow-up. AI was used to measure effusion volume as an independent reader. Agreement between human readers and AI was assessed using absolute difference in volume (DV), Coefficients of Variation (CoV) and intraclass correlation coefficient (ICC).

Results:

Effusion regions detected by AI closely correlated with manual segmentation (Figure 1) for all samples. Differences in volumes measured by each pair of readers are summarized in Table 1. Agreement was excellent between human readers (ICC=0.99) and for each reader vs AI (ICC = 0.85-0.87).

Figure 1.

Mask overlays of regions of joint fluid detected by human readers (green, column 2) and AI (red, column 3) from 3 different patients. Raw MRI images are shown in column 1.

Table 1.

Comparison of volumes measured in cubic millimeters and agreement between each pair of readers (with AI as the 3rd reader)

Volumes measured by readersAgreement between reader pairsReaderOverall VolumeMean ± Standard DeviationReader PairDifference in VolumeMean ± Standard DeviationCoVICCReader 16943 ± 5845Reader 1-21127 ± 9000.210.99 [0.98, 1.0]Reader 27638 ± 5619Reader 1-AI3311 ±16430.350.87 [0.7, 0.94]AI11014 ± 4454Reader 2-AI4151 ± 49860.270.85 [0.66,0.94]

Conclusion:

Initial results of automatic effusion measurement using AI show high agreement with human experts. This has potential to reduce variability and save expert time in OA MRI assessment, and to lead to improved OA care.

References:

[1]Sharif B, Garner R, Hennessy D, Sanmartin C, Flanagan WM, Marshall DA. Productivity costs of work loss associated with osteoarthritis in Canada from 2010 to 2031. Osteoarthritis Cartilage. 2017 Feb;25(2):249–58.

[2]Sharif B, Kopec J, Bansback N, Rahman MM, Flanagan WM, Wong H, et al. Projecting the direct cost burden of osteoarthritis in Canada using a microsimulation model. Osteoarthritis Cartilage. 2015 Oct;23(10):1654–63.

[3]Loeuille D, Chary-Valckenaere I, Champigneulle J, Rat A-C, Toussaint F, Pinzano-Watrin A, et al. Macroscopic and microscopic features of synovial membrane inflammation in the osteoarthritic knee: correlating magnetic resonance imaging findings with disease severity. Arthritis Rheum. 2005 Nov;52(11):3492–501.

[4]Fernandez-Madrid F, Karvonen RL, Teitge RA, Miller PR, An T, Negendank WG. Synovial thickening detected by MR imaging in osteoarthritis of the knee confirmed by biopsy as synovitis. Magn Reson Imaging. 1995;13(2):177–83.

[5]Atukorala I, Kwoh CK, Guermazi A, Roemer FW, Boudreau RM, Hannon MJ, et al. Synovitis in knee osteoarthritis: a precursor of disease? Ann Rheum Dis. 2016 Feb;75(2):390–5.

[6]Quinn-Laurin V, Thejeel B, Chauvin NA, Brandon TG, Weiss PF, Jaremko JL. Normal hip joint fluid volumes in healthy children of different ages, based on MRI volumetric quantitative measurement. Pediatr Radiol. 2020 Oct;50(11):1587–93.

[7]He K, Gkioxari G, Dollár P, Girshick R. Mask r-cnn. In: Proceedings of the IEEE international conference on computer vision. openaccess.thecvf.com; 2017. p. 2961–9.

Acknowledgements:

Jacob Jaremko is supported by the AHS Chair in Diagnostic Imaging at the University of Alberta. Medical Imaging Consultants (MIC) funds musculoskeletal radiology fellowships for Vanessa Quinn-Laurin at the University of Alberta, and provides Jacob Jaremko and Robert Lambert with protected academic time. Banafshe Felfeliyan is supported by an Alberta Innovates Graduate Student Scholarship for Data-Enabled Innovation.

Disclosure of Interests:

None declared.

Single-digit cold-induced vasodilation adaptations during an Antarctic expedition

An increasing number of people are spending time in Polar Regions for work and tourism and this can increase the risk of tissue injuries, e.g. frostbite. The risk would be reduced if beneficial peripheral blood flow adaptions occurred but data regarding the trainability of the cold-induced vasodilation (CIVD) response are equivocal. Five healthy males spent almost 8 months in Antarctica; five of them at a semi-permanent camp (− 44 °C; 2752 m). CIVD tests (30 min index finger immersion into 0 °C water) were performed on the 12th, 39–40th, 67–68th, 179th and 234th days of the expedition in a climate-controlled caboose. Heart rate (HR), thermal sensation of the finger, pain sensation, and mean arterial pressure (MAP) were recorded. Minimum, maximum, and mean finger temperature were greater, onset time was earlier (r = 0.34), and amplitude was greater (r = 0.55) on day 234 than day 12 suggesting that adaptation occurred. Time-point data suggested that the adaptations were progressive. Cardiovascular and perceptual data also showed some adaptation. MAP was lower on day 234 than day 12 (r = 0.47 and r = 0.47) but mean HR was higher (r = 0.55). Mean and peak thermal sensation (r = 0.31–0.59; r = 0.31) and perceived pain (r = 0.58; r = 0.36) both improved over the course of the expedition. Of interest to Polar Region visitors, beneficial peripheral and perceptual adaptations to prolonged Antarctic exposure can occur with 2 h of daily outdoor exposure although the rates at which adaptation occurs differ.

Parenting Styles and the Depressive Syndrome in Congenitally Blind Individuals

This article discusses the effect on congenitally blind children of three types of parents: those who are over-protective, those who push the child toward independence too soon, and those who are “good enough.” The authors focus on how the three styles of parenting affect the blind child's ability to give and receive and develop a sense of competence. These effects are discussed in the context of the ego ideal. The authors also examine the depressive core that is often the result of the blind child's inability to live up to the dictates of the ego ideal. Finally, they suggest a fourth style of parenting that would prepare blind children better for the problems they will encounter in the sighted world.

Preliminary Definitions for Sacroiliac Joint Pathologies in the OMERACT Juvenile Idiopathic Arthritis Magnetic Resonance Imaging Score (OMERACT JAMRIS-SIJ)

OBJECTIVE

To develop definitions for the assessment of magnetic resonance imaging (MRI) pathologies of the sacroiliac joints (SIJ) in juvenile idiopathic arthritis.

METHODS

An Outcome Measures in Rheumatology (OMERACT) consensus-driven methodology consisting of iterative surveys and focus group meetings within an international group of rheumatologists and radiologists.

RESULTS

Two domains, inflammation and structural, were identified. Definitions for bone marrow edema, joint space inflammation, capsulitis, and enthesitis were derived for joint inflammation; sclerosis, erosion, fatty lesion, and ankylosis were defined for assessing structural joint changes.

CONCLUSION

Preliminary consensus-driven definitions for inflammation and structural elements have been derived, underpinning the ongoing development of the OMERACT Juvenile Arthritis MRI SIJ scoring system (OMERACT JAMRIS-SIJ).

Antarctica eye study: a prospective study of the effects of overwintering on ocular parameters and visual function

BACKGROUND

In 2013 five polar explorers attempted to complete the first Trans-Antarctic Winter Traverse (TAWT). This study presents the ophthalmological findings for this group, who overwintered in Antarctica as part of the White Mars Human Science Protocol. Antarctic crews are exposed to extreme cold, chronic hypoxia and altered day-night cycles. Previous studies of Antarctic explorers have focused on the prolonged effect of ultraviolet radiation including the development of ultraviolet keratitis and accelerated cataract formation. This is the first study of its kind to investigate the effect of overwintering in Antarctica on the human eye.

METHODS

Pre and post-expedition clinical observations were made including visual acuity, contrast sensitivity, colour vision, auto-refraction, subjective refraction, retinal examination, retinal autofluoresence and retinal thickness, which were graded for comparison. During the expedition additional observations were made on a monthly basis including LogMAR visual acuity, autorefraction and intraocular pressure.

RESULTS

No significant differences between pre and post-expedition observations were found, including visual acuity, contrast sensitivity, colour vision, refraction, visual fields, intraocular pressure and retinal examination. There was a small but statistically significant decrease in retinal thickness across all regions of the retina, except for the macular and fovea, in all explorers. Intra-expedition observations remained within normal limits.

CONCLUSION

Reassuringly, the human eye remains largely unchanged by exposure to the extreme conditions encountered during the Antarctic winter, however, further research is needed to investigate changes in retinal thickness. This may have implications for scientists who spend prolonged periods of time in the polar regions, as well as those who have prolonged exposure to the extreme cold or chronic hypoxia in other settings.

Evidence that eating baked egg or milk influences egg or milk allergy resolution: a systematic review

BACKGROUND

It has been proposed that the frequent ingestion of baked hen's egg or cow's milk accelerates the resolution of hen's egg or cow's milk allergy. This practice is being introduced into clinical practice.

OBJECTIVE

To systematically review the evidence to determine whether the introduction of baked hen's egg or cow's milk into the diet of children with hen's egg or cow's milk allergies respectively leads to a larger proportion of children outgrowing these allergies than expected.

METHODS

A systematic review of the literature was conducted in Medline, Embase and CINAHL. The inclusion criteria were as follows: randomized control trials, case-control or cohort studies; children aged 0-18 years with hen's egg or cow's milk allergy; baked hen's egg or cow's milk intervention with or without a comparator; and resolution of the hen's egg or cow's milk allergy as determined by food challenge as the outcome. Studies were critically appraised using the quality assessment tool for quantitative studies. PROSPERO reference CRD42015026029.

RESULTS

We identified 851 and 2816 hen's egg and cow's milk articles respectively. Only three hen's egg and three cow's milk studies fulfilled our pre-specified inclusion criteria. The studies concluded that baked products either increased the likelihood of the resolution of allergy or accelerated resolution. However, when critiqued, all studies were classified as weak because they were observational, lacking an appropriate control group; this brings into doubt the study's conclusions. There were a number of examples of severe reactions to baked products.

CONCLUSION

There is little evidence to address the hypothesis that the ingestion of baked hen's egg or cow's milk results in more patients outgrowing their hen's egg or cow's milk allergy respectively. Data are required from a trial comparing the resolution rates of baked-tolerant participants who are randomized to ingest or avoid baked products to assess the accuracy of this hypothesis.

Ultrasound-guided aspiration and injection of an intraneural ganglion cyst of the common peroneal nerve

BACKGROUND

Intraneural ganglion cysts are rare, benign, mucinous lesions that occur within neural sheaths and are thought to involve cystic fluid exiting from nearby synovial joints. They often present as tender masses causing paresthesias in the distribution of the involved nerve, muscle weakness or cramping, or localized or referred pain.

CASE DESCRIPTION

We present a case of a patient who initially presented with foot drop due to an intraneural ganglion cyst of the common peroneal nerve. This cyst was successfully treated using ultrasound guidance to aspirate the cyst and inject corticosteroid to prevent further inflammation.

LITERATURE REVIEW

Standard of care has previously involved surgical resection, but this has been associated with a high frequency of recurrence. Due to the risks of nerve and vessel damage, there have been efforts to find alternative ways of resolving these cysts.

PURPOSES AND CLINICAL RELEVANCE

Aspiration and injection of corticosteroid is a useful and minimally invasive alternative to surgery for managing intraneural ganglion cysts.

European guidelines for quality assurance in colorectal cancer screening and diagnosis: overview and introduction to the full supplement publication

Population-based screening for early detection and treatment of colorectal cancer (CRC) and precursor lesions, using evidence-based methods, can be effective in populations with a significant burden of the disease provided the services are of high quality. Multidisciplinary, evidence-based guidelines for quality assurance in CRC screening and diagnosis have been developed by experts in a project co-financed by the European Union. The 450-page guidelines were published in book format by the European Commission in 2010.  They include 10 chapters and over 250 recommendations, individually graded according to the strength of the recommendation and the supporting evidence. Adoption of the recommendations can improve and maintain the quality and effectiveness of an entire screening process, including identification and invitation of the target population, diagnosis and management of the disease and appropriate surveillance in people with detected lesions. To make the principles, recommendations and standards in the guidelines known to a wider professional and scientific community and to facilitate their use in the scientific literature, the original content is presented in journal format in an open-access Supplement of Endoscopy. The editors have prepared the present overview to inform readers of the comprehensive scope and content of the guidelines.

European guidelines for quality assurance in colorectal cancer screening and diagnosis. First Edition--Annotations of colorectal lesions

Multidisciplinary, evidence-based guidelines for quality assurance in colorectal cancer screening and diagnosis have been developed by experts in a project coordinated by the International Agency for Research on Cancer. The full guideline document covers the entire process of population-based screening. It consists of 10 chapters and over 250 recommendations, graded according to the strength of the recommendation and the supporting evidence. The 450-page guidelines and the extensive evidence base have been published by the European Commission. The chapter on quality assurance in pathology was supplemented by an annex describing in greater detail some issues raised in the chapter, particularly details of special interest to pathologists. The content of the annex is presented here to promote international discussion and collaboration by making the issues discussed in the guidelines known to a wider professional and scientific community.

European guidelines for quality assurance in colorectal cancer screening and diagnosis. First Edition--Quality assurance in pathology in colorectal cancer screening and diagnosis

Multidisciplinary, evidence-based guidelines for quality assurance in colorectal cancer screening and diagnosis have been developed by experts in a project coordinated by the International Agency for Research on Cancer. The full guideline document covers the entire process of population-based screening. It consists of 10 chapters and over 250 recommendations, graded according to the strength of the recommendation and the supporting evidence. The 450-page guidelines and the extensive evidence base have been published by the European Commission. The chapter on quality assurance in pathology in colorectal cancer screening and diagnosis includes 23 graded recommendations. The content of the chapter is presented here to promote international discussion and collaboration by making the principles and standards recommended in the new EU Guidelines known to a wider professional and scientific community. Following these recommendations has the potential to enhance the control of colorectal cancer through improvement in the quality and effectiveness of the screening process, including multi-disciplinary diagnosis and management of the disease.

European guidelines for quality assurance in colorectal cancer screening and diagnosis. First Edition--Management of lesions detected in colorectal cancer screening

Multidisciplinary, evidence-based guidelines for quality assurance in colorectal cancer screening and diagnosis have been developed by experts in a project coordinated by the International Agency for Research on Cancer. The full guideline document covers the entire process of population-based screening. It consists of 10 chapters and over 250 recommendations, graded according to the strength of the recommendation and the supporting evidence. The 450-page guidelines and the extensive evidence base have been published by the European Commission. The chapter on management of lesions detected in colorectal cancer screening includes 32 graded recommendations. The content of the chapter is presented here to promote international discussion and collaboration by making the principles and standards recommended in the new EU Guidelines known to a wider professional and scientific community. Following these recommendations has the potential to enhance the control of colorectal cancer through improvement in the quality and effectiveness of the screening process, including multi-disciplinary diagnosis and management of the disease.

European guidelines for quality assurance in colorectal cancer screening and diagnosis. First Edition--Professional requirements and training

Multidisciplinary, evidence-based guidelines for quality assurance in colorectal cancer screening and diagnosis have been developed by experts in a project coordinated by the International Agency for Research on Cancer. The full guideline document covers the entire process of population-based screening. It consists of 10 chapters and over 250 recommendations, graded according to the strength of the recommendation and the supporting evidence. The 450-page guidelines and the extensive evidence base have been published by the European Commission. The chapter on professional requirements and training includes 23 graded recommendations. The content of the chapter is presented here to promote international discussion and collaboration by making the principles and standards recommended in the new EU Guidelines known to a wider professional and scientific community. Following these recommendations has the potential to enhance the control of colorectal cancer through improvement in the quality and effectiveness of surveillance and other elements in the screening process, including multi-disciplinary diagnosis and management of the disease.

European guidelines for quality assurance in colorectal cancer screening and diagnosis. First Edition--Colonoscopic surveillance following adenoma removal

Multidisciplinary, evidence-based guidelines for quality assurance in colorectal cancer screening and diagnosis have been developed by experts in a project coordinated by the International Agency for Research on Cancer. The full guideline document covers the entire process of population-based screening. It consists of 10 chapters and over 250 recommendations, graded according to the strength of the recommendation and the supporting evidence. The 450-page guidelines and the extensive evidence base have been published by the European Commission. The chapter on colonoscopic surveillance following adenoma removal includes 24 graded recommendations. The content of the chapter is presented here to promote international discussion and collaboration by making the principles and standards recommended in the new EU Guidelines known to a wider professional and scientific community. Following these recommendations has the potential to enhance the control of colorectal cancer through improvement in the quality and effectiveness of surveillance and other elements in the screening process, including multi-disciplinary diagnosis and management of the disease.

European guidelines for quality assurance in colorectal cancer screening and diagnosis. First Edition--Quality assurance in endoscopy in colorectal cancer screening and diagnosis

Multidisciplinary, evidence-based guidelines for quality assurance in colorectal cancer screening and diagnosis have been developed by experts in a project coordinated by the International Agency for Research on Cancer. The full guideline document covers the entire process of population-based screening. It consists of 10 chapters and over 250 recommendations, graded according to the strength of the recommendation and the supporting evidence. The 450-page guidelines and the extensive evidence base have been published by the European Commission. The chapter on quality assurance in endoscopy includes 50 graded recommendations. The content of the chapter is presented here to promote international discussion and collaboration by making the principles and standards recommended in the new EU Guidelines known to a wider professional and scientific community. Following these recommendations has the potential to enhance the control of colorectal cancer through improvement in the quality and effectiveness of endoscopy and other elements in the screening process, including multidisciplinary diagnosis and management of the disease.

Effects of cement or lime on Cd, Co, Cu, Ni, Pb, Sb and Zn mobility in field-contaminated and aged soils

Cement or lime can be used to treat trace element contaminated soils, reducing their mobility due to increased soil pH which enhances precipitation and adsorption, and also due to pozzolanic reactions and cementation. In the present work, an alkaline and an acidic soil both containing Cd, Co, Cu, Ni, Pb, Sb and Zn from either geogenic or geogenic and anthropogenic origin were treated with cement or calcium hydroxide. Soils were then extracted with dilute HNO(3) or NaOH solution of different concentrations to obtain extracts of different pH (pH 4-12). In untreated soils, Co, Cu, Ni and Pb in solutions were detected at alkaline pH. The addition of cement or Ca(OH)(2) reduced the mobility of every trace element at high pH, but enhanced the mobility of Cd, Co, Cu, Ni, Pb and Zn at low pH. Metal mobilisation at high pH was observed for Cu in the acidic soil due to the liberation of dissolved organic matter. Below pH 6, Sb mobility was lower in the cement-treated soil compared to the untreated soil, but the same in the Ca(OH)(2) treated soil as in the control soil. Comparison with theoretical trace element precipitates suggested that the mobility of trace elements is likely reduced at high pH by encapsulation and immobilisation within the cement matrix rather then precipitation.

Usefulness of colonoscopic examination with indigo carmine in diagnosing microscopic colitis

Microscopic colitis, comprising collagenous colitis and lymphocytic colitis, is epitomized by chronic watery diarrhea, endoscopically normal colonic mucosa, and characteristic histopathological features. Reports on chromoendoscopic findings in microscopic colitis are scarce and in this paper we describe such findings. We have examined 13 patients with microscopic colitis by means of chromoendoscopy with indigo carmine 0.2 % - 0.5 %. In all 13 cases continuous mucosal changes were seen, with disappearance of innominate grooves or with irregularity of grooves. The segmental distribution of abnormal chromoendoscopic findings corresponded almost completely with the microscopic features. A diffuse mosaic pattern was found in five of 10 cases of collagenous colitis and in all three cases of lymphocytic colitis. Uneven surface was seen in four cases of collagenous colitis, one of collagenous colitis in remission, and one of lymphocytic colitis, and a nodular surface was recorded in five cases of collagenous colitis but in none of the lymphocytic colitis cases. If these findings can be reproduced in larger series of microscopic colitis cases, the need for biopsies as a diagnostic tool might be restricted to patients where chromoendoscopy shows clear mucosal changes, thereby saving costs and limiting possible complications associated with multiple biopsies.

Serum procalcitonin, interleukin-6, soluble intercellular adhesin molecule-1 and IgG to short-chain exocellular lipoteichoic acid as predictors of infection in total joint prosthesis revision

The diagnosis of prosthetic joint infection and its differentiation from aseptic loosening remains problematic. The definitive laboratory diagnostic test is the recovery of identical infectious agents from multiple intraoperative tissue samples; however, interpretation of positive cultures is often complex as infection is frequently associated with low numbers of commensal microorganisms, in particular the coagulase-negative staphylococci (CNS). In this investigation, the value of serum procalcitonin (PCT), interleukin-6 (IL-6) and soluble intercellular adhesion molecule-1 (sICAM-1) as predictors of infection in revision hip replacement surgery is assessed. Furthermore, the diagnostic value of serum IgG to short-chain exocellular lipoteichoic acid (sce-LTA) is assessed in patients with infection due to CNS. Presurgical levels of conventional serum markers of infection including C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and white blood cell count (WBC) is also established. Forty-six patients undergoing revision hip surgery were recruited with a presumptive clinical diagnosis of either septic (16 patients) or aseptic loosening (30 patients). The diagnosis was confirmed microbiologically and levels of serum markers were determined. Serum levels of IL-6 and sICAM-1 were significantly raised in patients with septic loosening (P = 0.001 and P = 0.0002, respectively). Serum IgG to sce-LTA was elevated in three out of four patients with infection due to CNS. In contrast, PCT was not found to be of value in differentiating septic and aseptic loosening. Furthermore, CRP, ESR and WBC were significantly higher (P = 0.0001, P = 0.0001 and P = 0.003, respectively) in patients with septic loosening. Serum levels of IL-6, sICAM-1 and IgG to sce-LTA may provide additional information to facilitate the diagnosis of prosthetic joint infection.

ASDAS, BASDAI and different treatment responses and their relation to biomarkers of inflammation, cartilage and bone turnover in patients with axial spondyloarthritis treated with TNFα inhibitors

OBJECTIVES

To investigate the relation between ankylosing spondylitis disease activity score (ASDAS), Bath ankylosing spondylitis disease activity index (BASDAI) and treatment response and biomarkers of inflammation (C-reactive protein (CRP), interleukin-6 (IL-6), YKL-40), angiogenesis (vascular endothelial growth factor (VEGF)), cartilage (C-terminal crosslinking telopeptide of type II collagen (CTX-II), matrix metalloproteinase-3 (MMP-3), total aggrecan, cartilage oligomeric matrix protein) and bone (C-terminal crosslinking telopeptide of type I collagen, osteocalcin) turnover in 60 patients with axial spondyloarthritis initiating tumour necrosis factor alpha (TNFα) inhibitor therapy.

METHODS

ASDAS (CRP-based), BASDAI and biomarkers were determined before and seven times during 46 weeks of TNFα inhibitor therapy.

RESULTS

Very high ASDAS were associated with high levels of inflammatory biomarkers, while high BASDAI were not related to any biomarkers. Mixed modeling demonstrated significant longitudinal associations between ASDAS and IL-6, VEGF, MMP-3 and osteocalcin and between BASDAI and CRP, IL-6 and VEGF. Major improvement in ASDAS was associated with larger percentage decreases in biomarkers of inflammation, angiogenesis, MMP-3 and increases in aggrecan and osteocalcin. BASDAI response was associated with larger decreases in CRP and IL-6. Biomarkers with moderate/high differences in responsiveness for major versus no/clinically important improvement in ASDAS were CRP, IL-6, VEGF, aggrecan and osteocalcin, and VEGF and CTX-II for BASDAI response versus non-response.

CONCLUSION

Levels and changes of 10 biomarkers in patients with axial spondyloarthritis during anti-TNFα therapy were documented. Construct validity and responsiveness of IL-6, VEGF, MMP-3, total aggrecan and osteocalcin were demonstrated. ASDAS was more associated with these biomarkers than BASDAI, and may better reflect the inflammatory disease processes. ClinicalTrials.gov identifier NCT00133315.

Multiplane imaging and three dimensional nanoscale particle tracking in biological microscopy

A conventional microscope produces a sharp image from just a single object-plane. This is often a limitation, notably in cell biology. We present a microscope attachment which records sharp images from several object-planes simultaneously. The key concept is to introduce a distorted diffraction grating into the optical system, establishing an order-dependent focussing power in order to generate several images, each arising from a different object-plane. We exploit this multiplane imaging not just for bio-imaging but also for nano-particle tracking, achieving approximately 10 nm z position resolution by parameterising the images with an image sharpness metric.

[Colonoscopy: maximizing detection and characterization]

The endoscopic analysis of the colonic lumen with a flexible tube began around1960, at first with a gastrocamera, then with a fibrocolonoscope. After 1990, the electronic imaging brought a three points revolution with increased resolution of the image, transfer of the image on a television monitor giving access to multiple observers, electronic image processing. The recent colonoscopes have an increased resolution with more pixels in the Charged Coupled Device (CCD) sensor, a High Definition Television (HDTV) image and an electronic and/or optical zoom for magnification. Colonoscopy is now often performed in a similar environment to that of surgery. Therapeutic applications justify a strict strategy for endoscopic diagnosis. At first, detection of the lesion in standard vision, then characterization with the help of chromoscopy for the evaluation of morphology and with the help of magnification for the evaluation of the pit pattern. Then, comes the time for treatment decision between abstention, endoscopic resection or surgery. The legitimacy of the management is controlled in retrospective by the analysis of the tissue samples. Recent alternatives to colonoscopy (3D radiological imaging, colon capsule) should not invalidate the priority attributed to colonoscopy which associates treatment to the early detection of colorectal cancer and precursors.

Demonstration of effective control of fast-ion-stabilized sawteeth by electron-cyclotron current drive

In a tokamak plasma, sawtooth oscillations in the central temperature, caused by a magnetohydrodynamic instability, can be partially stabilized by fast ions. The resulting less frequent sawtooth crashes can trigger unwanted magnetohydrodynamic activity. This Letter reports on experiments showing that modest electron-cyclotron current drive power, with the deposition positioned by feedback control of the injection angle, can reliably shorten the sawtooth period in the presence of ions with energies >or=0.5 MeV. Certain surprising elements of the results are evaluated qualitatively in terms of existing theory.