J Callicott | PubMed Health

PubMed2001

Effectiveness of thin-layer preparations vs. conventional Pap smears in a blinded, split-sample study. Extended cytologic evaluation.

OBJECTIVE: To further evaluate the effectiveness of the AutoCyte PREP thin-layer slide preparation (TriPath Imaging, Inc., Burlington, North Carolina) as compared to conventional Pap smears. STUDY DESIGN: A split-sample, blinded evaluation of matched thin-layer preparations and conventional smears from 2,438 patients was performed. This material was enriched by including 260 cases of high grade squamous intraepithelial lesions (HSILs) and cancer cases from an earlier study. Many of these cases were difficult to diagnose, containing very few abnormal cells on one or both matching slides. The preparations were evaluated multiple times by both thin-layer-inexperienced and -experienced cytology professionals to better compare performance related to preparation quality alone. RESULTS: The initial evaluations of the slides by personnel with only brief training in thin-layer interpretation demonstrated equivalent performance for the two preparations. The reevaluation study by cytology professionals with several months of thin-layer experience demonstrated a statistically significant improvement in detection of both LSIL and HSIL lesions using AutoCyte PREP slides. There was also a statistically significant improvement in the number of satisfactory samples using the AutoCyte PREP method. CONCLUSION: The study demonstrated that the AutoCyte PREP thin-layer slide preparation is at least equivalent to conventional Pap smears in the detection of LSIL and HSIL, even when evaluated by cytology professionals who have been newly trained in the thin-layer method and that, with increased experience, the thin-layer AutoCyte PREP slide preparation method showed a statistically significant improvement in disease detection.

Female↗

PubMed1996

fMRI applications in schizophrenia research.

fMRI has unique potential in the study of psychiatric patients, particularly in characterizing individual variations and changes over time. We have performed four studies of patients with schizophrenia, using three different fMRI acquisition protocols: (1) 3-D echo-shifted FLASH, a multishot volumetric approach; (2) 3-D PRESTO, a hybid of multishot and echo-planar imaging (EPI) methods that also acquires true volumetric data; and (3) a whole-brain isotropic, multislice EPI technique. Patients were studied during sensorimotor activation and during a novel "N back" working memory paradigm. In general, patients show normal sensorimotor activation responses, although motor cortical activation tends to be less completely lateralized. Prefrontal activation during working memory tends to be reduced in patients with schizophrenia even when performance is normal. A major potential confound in studying this patient population with fMRI is the effect of motion. We propose several methodological standards to address this problem, including comparisons of motion corrections parameters, voxel variances, and the use of an "internal activation standard."

Adult↗