Validation of a simple camera navigation trainer.

BACKGROUND: One laparoscopic skill that is rarely addressed is proper use of the 30-degree laparoscope. Lack of knowledge and training with an angled laparoscope can result in less than optimal visualization. The purpose of this study is to validate a simple and efficient camera navigation trainer. STUDY DESIGN: Thirty-four medical students from Baylor College of Medicine participated. Their use of a 30-degree laparoscope was assessed. In task A, subjects were asked to demonstrate a series of views corresponding to the position of the light cord. In task B, subjects had to correctly demonstrate views of a three-dimensional model of a liver, intestines, and abdominal wall. Subjects then underwent a brief training session, followed by a self-directed, 10-minute practice session. Last, they were retested in tasks A and B. RESULTS: Sixteen students (47.1%) had prior experience using a laparoscope. At baseline testing, 0 of 34 novices were able to demonstrate the intended views in task A, but at posttraining the mean success rate was 99.5% (p < 0.0001). There was also significant improvement in performance of task B, where pretest success was 5.9% and posttest success was 98.5% (p < 0.0001). CONCLUSIONS: After a simple and brief training session, novices were able to effectively use the 30-degree laparoscope using the established verbal cues. The simplicity of this training module provides an efficient method of training novice camera operators both within and outside the operating room.

Estrogen receptor alpha expression in normal human breast epithelium is consistent over time.

If increased expression of estrogen receptor alpha (ER) in benign breast epithelium increases susceptibility to breast cancer, such overexpression should be stable over time. There are no published data regarding this important aspect of ER expression in breast epithelium. We examined the temporal consistency of ER expression in the normal breast tissue of 28 women who had 2 separate breast surgical procedures, at least 6 months apart (mean interval, 2.8 years). Paraffin embedded breast tissue blocks containing an adequate sample of normal breast epithelium and no cancer, were sectioned and processed using the 6F11 antibody and standard immunohistochemical techniques. The ER labelling index (ER LI) was calculated by counting a mean of 2,000 epithelial cells. The median ER LI at first sampling was 13.6 and at second sample 15.5, with R(2) = 0.34 and p = 0.001. The ER LI was categorized into high and low values, using a threshold of 10. Twenty-four women (85.7%) showed concordance of high and low expression between the 2 samples (p = 0.002). There were 11 women who were premenopausal at both time points. Among them, much of the variation in ER LI was explained by differences in the menstrual cycle day at the time of sampling and adding the day of cycle to the regression model substantially improved the correlation between first and second labeling indices. These data suggest that ER expression of normal breast tissue is fairly consistent over time and support the notion that overexpression of ER in normal epithelium is a constant feature of the high risk breast.