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Alvin Zfass

Publications and source records attributed to Alvin Zfass.

2 recordsLinked to original sources
PubMed2004

Computed tomographic colonography (virtual colonoscopy): a multicenter comparison with standard colonoscopy for detection of colorectal neoplasia.

CONTEXT: Conventional colonoscopy is the best available method for detection of colorectal cancer; however, it is invasive and not without risk. Computed tomographic colonography (CTC), also known as virtual colonoscopy, has been reported to be reasonably accurate in the diagnosis of colorectal neoplasia in studies performed at expert centers. OBJECTIVE: To assess the accuracy of CTC in a large number of participants across multiple centers. DESIGN, SETTING, AND PARTICIPANTS: A nonrandomized, evaluator-blinded, noninferiority study design of 615 participants aged 50 years or older who were referred for routine, clinically indicated colonoscopy in 9 major hospital centers between April 17, 2000, and October 3, 2001. The CTC was performed by using multislice scanners immediately before standard colonoscopy; findings at colonoscopy were reported before and after segmental unblinding to the CTC results. MAIN OUTCOME MEASURES: The sensitivity and specificity of CTC and conventional colonoscopy in detecting participants with lesions sized at least 6 mm. Secondary outcomes included detection of all lesions, detection of advanced lesions, possible technical confounders, participant preferences, and evidence for increasing accuracy with experience. RESULTS: A total of 827 lesions were detected in 308 of 600 participants who underwent both procedures; 104 participants had lesions sized at least 6 mm. The sensitivity of CTC for detecting participants with 1 or more lesions sized at least 6 mm was 39.0% (95% confidence interval [CI], 29.6%-48.4%) and for lesions sized at least 10 mm, it was 55.0% (95% CI, 39.9%-70.0%). These results were significantly lower than those for conventional colonoscopy, with sensitivities of 99.0% (95% CI, 97.1%->99.9%) and 100%, respectively. A total of 496 participants were without any lesion sized at least 6 mm. The specificity of CTC and conventional colonoscopy for detecting participants without any lesion sized at least 6 mm was 90.5% (95% CI, 87.9%-93.1%) and 100%, respectively, and without lesions sized at least 10 mm, 96.0% (95% CI, 94.3%-97.6%) and 100%, respectively. Computed tomographic colonography missed 2 of 8 cancers. The accuracy of CTC varied considerably between centers and did not improve as the study progressed. Participants expressed no clear preference for either technique. CONCLUSIONS: Computed tomographic colonography by these methods is not yet ready for widespread clinical application. Techniques and training need to be improved.

Colonography, Computed Tomographic↗
PubMed2002

Short course of omeprazole: a better first diagnostic approach to noncardiac chest pain than endoscopy, manometry, or 24-hour esophageal pH monitoring.

UNLABELLED: Noncardiac chest pain (NCCP) presents as a frequent diagnostic challenge, with patients tending to use a disproportionate level of health care resources. Gastroesophageal reflux disease (GERD) is the most frequent cause of NCCP. GOALS: To test the efficacy of a potent acid-suppressing agent as a diagnostic test in the evaluation of NCCP and to compare it with three commonly used tests. STUDY: Eighteen men and 24 women, aged 22 to 77 years, who presented with recurrent chest pain complaints of a noncardiac etiology, as determined by rest/stress perfusion imaging with technetium Tc99m sestamibi (MIBI), were enrolled in a prospective, double-blinded, placebo-controlled, crossover trial using high-dose omeprazole. Thirty-seven patients completed both arms of the trial. Findings were compared with those of endoscopy, manometry, and ambulatory 24-hour two-channel esophageal pH monitoring. All patients underwent initial diagnostic upper endoscopy, esophageal manometry, and 24-hour pH monitoring. Patients were then randomly assigned to either placebo or omeprazole (40 mg/d orally twice daily) for 14 days, washed out for 21 days, and then crossed over. Patient's symptoms were determined using a Visual Analogue Scale to measure the severity of chest pain before and after each period. RESULTS: Seventy-one percent of patients in the omeprazole arm reported improved chest pain, whereas only 18% in the placebo arm did. Abnormal results on manometry (20%), 24-hour pH monitoring (42%), or endoscopy with visual evidence of esophagitis (26%) were found less frequently. Combination of the three tests did not significantly increase their usefulness. In NCCP patients with GERD, as defined by positive results on a 24-hour pH test or presence of esophagitis on endoscopy, omeprazole treatment led to a response in 95% of patients, whereas 90% of GERD-positive patients treated with placebo did not respond. Of NCCP patients determined to be GERD negative, 39% responded to omeprazole. CONCLUSIONS: Omeprazole as a first diagnostic tool in the evaluation of MIBI-negative NCCP is sensitive and specific for determining the cause of NCCP. Endoscopy, manometry, and 24-hour pH monitoring were not only less sensitive in diagnosing NCCP, but they were significantly more expensive.

Adult↗