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Dobben AC Terra MP Deutekom M Gerhards MF Bijnen AB Felt-Bersma RJ Janssen LW Bossuyt PM Stoker J 《International journal of colorectal disease》2007,22(7):783-790
Background Anal inspection and digital rectal examination are routinely performed in fecal incontinent patients but it is not clear to
what extent they contribute to the diagnostic work-up. We examined if and how findings of anal inspection and rectal examination
are associated with anorectal function tests and endoanal ultrasonography.
Methods A cohort of fecal incontinent patients (n=312, 90% females; mean age 59) prospectively underwent anal inspection and rectal
examination. Findings were compared with results of anorectal function tests and endoanal ultrasonography.
Results Absent, decreased and normal resting and squeeze pressures at rectal examination correlated to some extent with mean (±SD)
manometric findings: mean resting pressure 41.3 (±20), 43.8 (±20) and 61.6 (±23) Hg (p<0.001); incremental squeeze pressure
20.6 (±20), 38.4 (±31) and 62.4 (±34) Hg (p<0.001). External anal sphincter defects at rectal examination were confirmed with
endoanal ultrasonography for defects <90 degrees in 36% (37/103); for defects between 90-150 degrees in 61% (20/33); for defects
between 150-270 degrees in 100% (6/6). Patients with anal scar tissue at anal inspection had lower incremental squeeze pressures
(p=0.04); patients with a gaping anus had lower resting pressures (p=0.013) at anorectal manometry. All other findings were
not related to any anorectal function test or endoanal ultrasonography.
Conclusions Anal inspection and digital rectal examination can give accurate information about internal and external anal sphincter function
but are inaccurate for determining external anal sphincter defects <90 degrees. Therefore, a sufficient diagnostic work-up
should comprise at least rectal examination, anal inspection and endoanal ultrasonography. 相似文献
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External anal sphincter defects in patients with fecal incontinence: comparison of endoanal MR imaging and endoanal US 总被引:1,自引:0,他引:1
Dobben AC Terra MP Slors JF Deutekom M Gerhards MF Beets-Tan RG Bossuyt PM Stoker J 《Radiology》2007,242(2):463-471
PURPOSE: To prospectively compare in a multicenter study the agreement between endoanal magnetic resonance (MR) imaging and endoanal ultrasonography (US) in depicting external anal sphincter (EAS) defects in patients with fecal incontinence. MATERIALS AND METHODS: The study was approved by the medical ethics committee of all participating centers. A total of 237 consenting patients (214 women, 23 men; mean age, 58.6 years +/- 13 [standard deviation]) with fecal incontinence were examined from 13 different hospitals by using endoanal MR imaging and endoanal US. Patients with an anterior EAS defect depicted on endoanal MR images and/or endoanal US scans underwent anal sphincter repair. Surgical findings were used as the reference standard in the determination of anterior EAS defects. The Cohen kappa statistic and McNemar test were used to calculate agreement and differences between diagnostic techniques. RESULTS: Agreement between endoanal MR imaging and endoanal US was fair for the depiction of sphincter defects (kappa = 0.24 [95% confidence interval: 0.12, 0.36]). At surgery, EAS defects were found in 31 (86%) of 36 patients. There was no significant difference between MR imaging and US in the depiction of sphincter defects (P = .23). Sensitivity and positive predictive value were 81% and 89%, respectively, for endoanal MR imaging and 90% and 85%, respectively, for endoanal US. CONCLUSION: In the selection of patients for anal sphincter repair, both endoanal MR imaging and endoanal US are sensitive tools for preoperative assessment, and both techniques can be used to depict surgically repairable anterior EAS defects. 相似文献
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RATIONALE AND OBJECTIVES: Meta-analyses of diagnostic accuracy studies produce summary estimates of sensitivity and specificity. Cancer staging relies on staging systems and meta-analysis is often performed after dichotomization of the staging results. For each dichotomization, summary estimates of sensitivity and specificity can be calculated by repeated bivariate random-effects analyses. In this process, staging information is lost and under- and overstaging can not be adequately expressed. MATERIALS AND METHODS: We propose a new multivariate random-effects approach, which is an extension of the bivariate random-effects approach. To illustrate the principles and outcomes of both approaches, we used data from a meta-analysisevaluating endoluminal ultrasonography in staging of rectal cancer. In the multivariate approach, results on correct staging and under- and overstaging were calculated. In addition, the results from this analysis were used to calculate sensitivity and specificity estimates for each dichotomization and these estimates were compared with the results of the repeated bivariate analyses. RESULTS: By the multivariate analysis, results on correct staging and under- and overstaging were obtained. The sensitivity and specificity estimates for the dichotomizations, calculated from the results of this multivariate approach, were also comparable with the sensitivity and specificity estimates obtained by the repeated bivariate analyses. CONCLUSIONS: The multivariate random-effects approach can be a useful meta-analytic method for summarizing cancer staging data presented in diagnostic accuracy studies. 相似文献
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Keyaerts M Lahoutte T Neyns B Caveliers V Vanhove C Everaert H Kersemans K Franken PR Mertens J Bossuyt A 《European journal of nuclear medicine and molecular imaging》2007,34(7):994-1002
Purpose
123I-2-iodo-tyrosine (123I-2IT) has been identified as a promising new amino acid tracer in animals. Uptake is mediated by LAT1 transport, which is
increased in tumour cells. In this study we present the human biodistribution and first clinical results in glioma patients.
Methods For the biodistribution study, six male volunteers received 60–95 MBq 123I-2IT. Whole-body scans and blood and urine samples were obtained up to 24 h after injection; dosimetry was calculated using
OLINDA 1.0 software. Initial clinical evaluation of 123I-2IT SPECT was performed in 35 patients with suspected or known glioma, either as primary diagnosis or for detection of recurrence.
Tumour-to-background (T/B) ratios were calculated for semi-quantitative analysis. The results were correlated with clinical
and MRI follow-up data or histology.
Results
123I-2IT showed both renal and intestinal clearance. Bladder (0.12 mGy/MBq) and small intestine (0.03 mGy/MBq) received the highest
absorbed doses. The effective dose equivalent and effective dose were estimated at 0.020 and 0.016 mSv/MBq, respectively.
In patients, 123I-2IT SPECT did not differentiate between neoplastic and non-neoplastic lesions after an indeterminate MRI. In follow-up of
known glioma, 13/15 patients with disease recurrence had increased T/B values (range 1.39–3.91). Out of seven recurrence-negative
patients, two showed an important increase in T/B, in one case due to radionecrosis (T/B 1.59) and in the other probably due
to residual but stable disease (T/B 2.07).
Conclusion
123I-2IT has a favourable biodistribution for a tumour imaging agent. It shows increased uptake in central nervous system glioma
and is potentially useful in the follow-up of glioma patients.
M. Keyaerts is an “aspirant” of the FWO-Vlaanderen. 相似文献