Accuracy of Capsule Colonoscopy in Detecting Colorectal Polyps in a Screening Population

BACKGROUND & AIMS: Capsule colonoscopy is a minimally invasive imaging method. We measured the accuracy of this technology in detecting polyps 6 mm or larger in an average-risk screening population. METHODS: In a prospective study, asymptomatic subjects (n = 884) underwent capsule colonoscopy followed by conventional colonoscopy (the reference) several weeks later, with an endoscopist blinded to capsule results, at 10 centers in the United States and 6 centers in Israel from June 2011 through April 2012. An unblinded colonoscopy was performed on subjects found to have lesions 6 mm or larger by capsule but not conventional colonoscopy. RESULTS: Among the 884 subjects enrolled, 695 (79%) were included in the analysis of capsule performance for all polyps. There were 77 exclusions (9%) for inadequate cleansing and whole-colon capsule transit time fewer than 40 minutes, 45 exclusions (5%) before capsule ingestion, 15 exclusions (2%) after ingestion and before colonoscopy, and 15 exclusions (2%) for site termination. Capsule colonoscopy identified subjects with 1 or more polyps 6 mm or larger with 81% sensitivity (95% confidence interval [CI], 77%-84%) and 93% specificity (95% CI, 91%-95%), and polyps 10 mm or larger with 80% sensitivity (95% CI, 74%-86%) and 97% specificity (95% CI, 96%-98%). Capsule colonoscopy identified subjects with 1 or more conventional adenomas 6 mm or larger with 88% sensitivity (95% CI, 82%-93) and 82% specificity (95% CI, 80%-83%), and 10 mm or larger with 92% sensitivity (95% CI, 82%-97%) and 95% specificity (95% CI, 94%-95%). Sessile serrated polyps and hyperplastic polyps accounted for 26% and 37%, respectively, of false-negative findings from capsule analyses. CONCLUSIONS: In an average-risk screening population, technically adequate capsule colonoscopy identified individuals with 1 or more conventional adenomas 6 mm or larger with 88% sensitivity and 82% specificity. Capsule performance seems adequate for patients who cannot undergo colonoscopy or who had incomplete colonoscopies. Additional studies are needed to improve capsule detection of serrated lesions. Clinicaltrials.gov number: NCT01372878

The modern self in the labyrinth : a study of entrapment in the works of Weber, Freud, and Foucault

In the works of Weber, Freud, and Foucault we find a distinct depiction of the relation between the self and modern civilization. This thesis describes that relation as "entrapment": the self has become mired in the life orders of modernity and is unable to reign over them. The primary hazard of these orders is their imposition of subjectivities that are highly circumscribed, subjectivities more responsive to external functions and imperatives than to the expression of individuality. Underlying this outlook is a new consciousness of time; in lieu of evolutionary and progressive theories of history, a tragic view emerges. History is seen as devoid of any deterministic necessity, yet its collective products have become too weighty and entrenched to allow for radical, over-arching political transformations. The thesis examines how, beginning with these shared presuppositions, Weber, Freud, and Foucault develop very different understandings of entrapment, understandings that pose fundamental challenges to one another

Degeneration Modulates Retinal Response to Transient Exogenous Oxidative Injury

<div><p>Purpose</p><p>Oxidative injury is involved in retinal and macular degeneration. We aim to assess if retinal degeneration associated with genetic defect modulates the retinal threshold for encountering additional oxidative challenges.</p><p>Methods</p><p>Retinal oxidative injury was induced in degenerating retinas (rd10) and in control mice (WT) by intravitreal injections of paraquat (PQ). Retinal function and structure was evaluated by electroretinogram (ERG) and histology, respectively. Oxidative injury was assessed by immunohistochemistry for 4-Hydroxy-2-nonenal (HNE), and by Thiobarbituric Acid Reactive Substances (TBARS) and protein carbonyl content (PCC) assays. Anti-oxidant mechanism was assessed by quantitative real time PCR (QPCR) for mRNA of antioxidant genes and genes related to iron metabolism, and by catalase activity assay.</p><p>Results</p><p>Three days following PQ injections (1 µl of 0.25, 0.75, and 2 mM) the average ERG amplitudes decreased more in the WT mice compared with the rd10 mice. For example, following 2 mM PQ injection, ERG amplitudes reduced 1.84-fold more in WT compared with rd10 mice (p = 0.02). Injection of 4 mM PQ resulted in retinal destruction. Altered retina morphology associated with PQ was substantially more severe in WT eyes compared with rd10 eyes. Oxidative injury according to HNE staining and TBARS assay increased 1.3-fold and 2.1-fold more, respectively, in WT compared with rd10 mice. At baseline, prior to PQ injection, mRNA levels of antioxidant genes (<i>Superoxide Dismutase1, Glutathione Peroxidase1, Catalase</i>) and of <i>Transferrin</i> measured by quantitative PCR were 2.1–7.8-fold higher in rd10 compared with WT mice (p<0.01 each), and catalase activity was 1.7-fold higher in rd10 (p = 0.0006).</p><p>Conclusions</p><p>This data suggests that degenerating rd10 retinas encounter a relatively lower degree of damage in response to oxidative injury compared with normal retinas. Constitutive up-regulation of the oxidative defense mechanism in degenerating retinas may confer such relative protection from oxidative injury.</p></div

Scotopic b-wave ERG responses following intravitreal injection of PQ.

<p>ERGs were recorded three days following injection of 4(A,B), 2 mM (C,D), 0.75 mM (E,F), or 0.25 mM (G,H) of PQ in one eye and PBS in the fellow eye of wild type (WT) and rd10 mice (n = 10–22 in each group). Y-axis shows amplitude in microvolt while the x-axis shows the stimulus intensity.</p

Retinal Expression of antioxidant genes in rd10 and WT mice.

<p>(A) mRNA levels of anti-oxidant enzymes in normal and degenerating retinas. <i>SOD1</i>, <i>GPX1,</i> and <i>CAT</i> expression levels were measured using QPCR (rd10 n = 7 pairs, WT n = 4 pairs). (B) Catalase activity evaluated in retinas of three-week-old WT and rd10 mice. *p<0.05 in comparison to WT (n = 5 in each group).</p