From the surface to the single cell: Novel endoscopic approaches in inflammatory bowel disease

Inflammatory bowel diseases (IBD) comprise the two major entities Crohn's disease and ulcerative colitis and endoscopic imaging of the gastrointestinal tract has always been an integral and central part in the management of IBD patients. Within the recent years, mucosal healing emerged as a key treatment goal in IBD that substantially decides about the clinical outcome of IBD patients, thereby demanding for a precise, timely and detailed endoscopic assessment of the mucosal inflammation associated with IBD. Further, molecular imaging has tremendously expanded the clinical utility and applications of modern endoscopy, now encompassing not only diagnosis, surveillance, and treatment but also the prediction of individual therapy response. Within this review we describe novel endoscopic approaches and advanced endoscopic imaging methods for the diagnosis, treatment and surveillance of IBD patients. We begin by providing an overview over novel and advanced imaging techniques such as magnification endoscopy and dye-based and dye-less chromoendoscopy, endomicroscopy and endocytoscopy. We then describe how these techniques can be utilized for the precise and ultrastructural assessment of mucosal inflammation and dysplasia development associated with IBD and outline how they have enabled the endoscopist to gain insight onto the cellular level in real-time. Finally, we provide an outlook on how molecular imaging has rapidly evolved in the recent past and can be used to make individual predictions about the therapeutic response towards biological treatment

Review article: newer optical and digital chromoendoscopy techniques vs. dye-based chromoendoscopy for diagnosis and surveillance in inflammatory bowel disease

BackgroundRecent innovations in gastrointestinal endoscopy have changed our traditional approach to diagnosis and therapy in patients with inflammatory bowel diseases (IBD). While traditionally used dye-based chromoendoscopy (DBC) techniques suffer from several limitations that reduce their utility in daily routine practice, newer dye-less' chromoendoscopy (DLC) techniques offer a great potential to overcome most of these limitations. AimTo review available optical and digital chromoendoscopy techniques, by critically discussing their potential for diagnostic and surveillance colonoscopy in patients with IBD. MethodsA literature search on the use of dye-less and dye-based chromoendoscopy in IBD patients was performed. ResultsIn long-standing IBD, DBC improves detection of dysplasia (diagnostic odds ratio=17.5, 95% CI=1.2-247.1) as well as prediction of inflammatory disease activity and extent of disease compared with standard video-colonoscopy. Narrow band imaging (NBI) shows no improvement in dysplasia detection rates compared with white-light endoscopy and DBC (P=0.6). Moreover, NBI results in a suboptimal differentiation of dysplastic from nondysplastic lesions. No data regarding digital DLC techniques (i.e. FICE, i-scan) for dysplasia detection in IBD are yet available. Both NBI and i-scan are superior to white-light endoscopy in assessing the activity and extent of colorectal IBD. ConclusionsAlthough the potential benefits of newer optical and digital dye-less chromoendoscopy techniques over traditionally used DBC are substantial, only DBC can currently be recommended to improve dysplasia detection in long-standing IBD. In contrast, DLC has the potential to quantify disease activity and mucosal healing in IBD

3-D focused inversion of near-seafloor magnetic data with application to the Brothers volcano hydrothermal system, Southern Pacific Ocean, New Zealand

Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 117 (2012): B10102, doi:10.1029/2012JB009349.We describe and apply a new inversion method for 3-D modeling of magnetic anomalies designed for general application but which is particularly useful for the interpretation of near-seafloor magnetic anomalies. The crust subsurface is modeled by a set of prismatic cells, each with uniform magnetization, that together reproduce the observed magnetic field. This problem is linear with respect to the magnetization, and the number of cells is normally greater than the amount of available data. Thus, the solution is obtained by solving an under-determined linear problem. A focused solution, exhibiting sharp boundaries between different magnetization domains, is obtained by allowing the amplitudes of magnetization to vary between a pre-determined range and by minimizing the region of the 3-D space where the source shows large variations, i.e., large gradients. A regularization functional based on a depth-weighting function is also introduced in order to counter-act the natural decay of the magnetic field intensity with depth. The inversion method has been used to explore the characteristics of the submarine hydrothermal system of Brothers volcano in the Kermadec arc, by inverting near-bottom magnetic data acquired by Autonomous Underwater Vehicles (AUVs). Different surface expressions of the hydrothermal vent fields show specific vertical structures in their underlying demagnetization regions that we interpret to represent hydrothermal upflow zones. For example, at focused vent sites the demagnetized conduits are vertical, pipe-like structures extending to depths of ~1000 m below the seafloor, whereas at diffuse vent sites the demagnetization regions are characterized by thin and inclined conduits.This contribution was made possible through funding by the New Zealand Foundation for Research, Science and Technology (FRST contract C05X0406) and by the Royal Society of New Zealand by the Marsden Fund (grant GNS1003).2013-04-1

Advanced endoscopic imaging for diagnosis of inflammatory bowel diseases : present and future perspectives

Crohn's disease and ulcerative colitis are chronic inflammatory bowel diseases (IBD) causing severe damage of the luminal gastrointestinal tract. Differential diagnosis between both disease entities is sometimes awkward requiring a multifactorial pathway, including clinical and laboratory data, radiological findings, histopathology and endoscopy. Apart from disease diagnosis, endoscopy in IBD plays a major role in prediction of disease severity and extent (i.e. mucosal healing) for tailored patient management and for screening of colitis-associated cancer and its precursor lesions. In this state-of-the-art review, we focus on current applications of endoscopy for diagnosis and surveillance of IBD. Moreover, we will discuss the latest guidelines on surveillance and provide an overview of the most recent developments in the field of endoscopic imaging and IBD

Metodologie magneto-gradiometriche applicate ad indagini marine di tipo ambientale all’interno del Mar Piccolo (Taranto)

La caratteristica fondamentale dei metodi di potenziale, è quella di aver il pregio di fornire una risposta relativamente rapida e non invasiva dell’oggetto in studio, che siano strutture geologiche (studi di tipo tettonico o minerario) o isolati corpi suscettivi sepolti (studi prettamente ambientali – relitti, discariche sottomarine, fusti metallici sepolti ecc..). Nei rilievi magnetici marini relativi a quest’ultimo caso, per ottenere dei risultati soddisfacenti, sono di fondamentale importanza alcuni requisiti quali un accurato sistema di posizionamento GPS, l’utilizzo di vettori navali amagnetici, una elevata sensibilità della strumentazione impiegata, e la corretta rimozione degli effetti temporali legati alle variazioni del Campo Magnetico terrestre. Quest’ultimo aspetto è assai delicato perché comporta la necessità di avere un osservatorio fisso coerente in misura durante l’esecuzione del rilievo. Per superare questo problema sono assai efficaci metodologie di tipo gradiometrico, che si basano sullo studio del gradiente orizzontale del Campo Magnetico terrestre, che si ottiene mediante l’acquisizione contemporanea di due misure (due sensori) poste ad una determinata distanza tra loro. I principali vantaggi introdotti dall’utilizzo di queste tecniche consistono principalmente in una significativa attenuazione dei contributi derivanti dalle sorgenti più profonde, la non necessità delle correzioni temporali ed in una maggiore rapidità nelle procedure di elaborazione dei dati. In questa ottica è stato condotto uno studio applicando questo tipo di metodologia in un contesto prettamente ambientale ovvero l’individuazione di corpi metallici in un’area ad elevato noise ambientale. L’area del rilievo è situata all’interno del Mar Piccolo di Taranto, a ridosso delle strutture portuali e si estende per circa 3 X 1,5 Km. I rilievi sono stati condotti utilizzando una piccola imbarcazione (idrobarca in GRP - Glass Renforced Plastic) trainante l’apparato di misura filato ad una distanza tale da non risentire del disturbo elettromagnetico generato dai motori e dalle apparecchiature di bordo. Problematiche relative ai bassi fondali dell’area rilevata (da 4 a 13 metri di battente d’acqua) hanno comportato la progettazione di un apposito catamarano in vetroresina (completamente amagnetico) a cui è stata fissata la sensoristica, così da poter navigare poco sotto il pelo dell’acqua; per motivi di navigabilità sono stati pianificate rotte principali in direzione Est-Ovest e traverse di controllo nelle aree con segnali ‘interessanti’. La strumentazione magnetometrica utilizzata (fig. 1) è costituita da due sensori a vapori di Cesio che sfruttano la tecnica del pompaggio ottico. La misura della frequenza viene effettuata con 10 letture al secondo, l’operatività è garantita in un range tra 20.000 – 100.000 nT e l’accuracy assoluta dipende da diversi fattori quali: l’orientazione del sensore, lo shift della luce interna e il tempo del frequency counter. L’errore dovuto all’orientazione risulta comunque compreso entro 1 nT. L’operatività viene garantita in un range da –35° e +50° di orientazione dei sensori. la sensibilità è di 0.02 nT con un intervallo di campionamento di 10 misure al secondo. Nonostante l’elevato noise ambientale causato dalla presenza di navi, bacini e altre sorgenti di noise legate alle attività portuali, sono stati evidenziati 9 punti anomali di interesse nella mappa del segnale gradiometrico (fig. 2). Le successive ispezioni dirette, hanno rilevato la presenza di evidenze (vari materiali di tipo ferroso e spezzoni di battelli) correlate alle anomalie di 7 punti tra quelli individuati a seguito dell’elaborazione dei dati

Integrated MVG and ERT Survey Over a Shallow Cave

An integrated geophysical MVG (Microgravity Vertical Gradient) and ERT (Electrical Resistivity Tomography) survey was performed over a shallow cave in the Armetta Mountain karst area, close to the Liguria-Piedmont wa- tershed (Tanaro valley). The aim of this study is to test the response of a known shallow karst cave. The cave was developed in the Mesozoic sedimen- tary cover (dolostones and limestones - CAU : Caprauna Armetta Unit); the shallowest portion of the cave exhibits narrow passages and, at about 30 m below the entrance, a fossil meander which links two large chambers, that represent the target of the geophysical survey....

Marine geomagnetic high definition metrology; possible archaeological applications

The marine geomagnetism is often used to solve geological problems at a regional scale: structural, volcanological or mining problems, for instance (Faggioni et al., 1995). In recent time, the development of the “high definition (HD) metrology” (Faggioni et al., 2001) has made the marine geomagnetic method suitable for detecting short wavelength and low amplitude geomagnetic anomalies. This type of signal may be often related to environmental and/or archaeological sources......

Magnetic Base Station Deceptions, a magnetovariational analysis along the Ligurian Sea coast, Italy

Reliability of high resolution airborne and shipborne magnetic surveys depends on accurate removal of temporal variations from the recorded total magnetic field intensity data. At mid latitudes, one or a few base stations are typically located within or near the survey area and are used to monitor and remove time dependent variations. These are usually assumed to be of external origin and uniform throughout the survey area. Here we investigate the influence on the magnetic base station correction of the time varying magnetic field variations generated by internal telluric currents flowing in anomalous regional 2D/3D conductivity structures. The study is based on the statistical analysis of a data set collected by four magnetovariational stations installed in northwestern Italy. The variometer stations were evenly placed with a spacing of about 60 km along a profile roughly parallel to the coastline. They recorded the geomagnetic field from the beginning to the end of April 2005, with a sampling rate of 0.33 Hz. Cross-correlation and coherence analysis applied to a subset of 125 five hours long magnetic events indicates that, for periods longer than 400 s, there is an high correlation between the horizontal magnetic field components at the different stations. This indicates spatial uniformity of the source field and of the induced currents in the 1D Earth. Additionally, the pattern of the induction arrows, estimated from single site transfer functions, reveals a clear electromagnetic signature of the Sestri-Voltaggio line, interpreted as a major regional tectonic boundary. Induced telluric currents flowing through this 2D/3D electrical conductivity discontinuity affect mainly the vertical magnetic component at the closer locations. By comparing this component at near (32 km) and far (70 km) stations, we have found that the mean value of the power spectra ratio, due to the electromagnetic induced field, is about 1.8 in the frequency band ranging from 2.5×10−3 to 5.5×10−5 Hz. This energy, folded in the spatial domain of an hypothetical survey in this region produces unwanted noise in the dataset. Considering a fifth of nyquist frequency the optimal tie-line spacing to assure complete noise removal would be 1 km and 15 km for a rover speed of 6 knots (marine magnetic survey) and 100 knots (aeromagnetic survey) respectively. Similar power spectra analysis can be applied elsewhere to optimise tie-line spacing for levelling and filtering parameters utlilised for microlevelling

The Offer of Advanced Imaging Techniques Leads to Higher Acceptance Rates for Screening Colonoscopy : a Prospective Study

BACKGROUND: Colonoscopy plays a fundamental role in early diagnosis and management of colorectal cancer and requires public and professional acceptance to ensure the ongoing success of screening programs. The aim of the study was to prospectively assess whether patient acceptance rates to undergo screening colonoscopy could be improved by the offer of advanced imaging techniques. MATERIALS AND METHODS: Overall, 372 randomly selected patients were prospectively included. A standardized questionnaire was developed that inquired of the patients their knowledge regarding advanced imaging techniques. Second, several media campaigns and information events were organized reporting about advanced imaging techniques, followed by repeated evaluation. After one year the evaluation ended. RESULTS: At baseline, 64% of the patients declared that they had no knowledge about new endoscopic methods. After twelve months the overall grade of information increased significantly from 14% at baseline to 34%. The percentage of patients who decided to undergo colonoscopy because of the offer of new imaging methods also increased significantly from 12% at baseline to 42% after 12 months. CONCLUSIONS: Patients were highly interested in the offer of advanced imaging techniques. Knowledge about these techniques could relatively easy be provided using local media campaigns. The offer of advanced imaging techniques leads to higher acceptance rates for screening colonoscopies