ABSTRACT
Advantages of the lensless Fourier holography setup for the reconstruction of digitally recorded holograms in holographic interferometry are presented. This very simple setup helps to achieve a maximum lateral resolution of the object under investigation. Also, the numerical-reconstruction algorithm is very simple and fast to compute. A mathematical model based on Fourier optics is used to describe discretization effects and to determine the lateral resolution. The recording and the reconstruction processes are regarded as an optical imaging system, and the point-spread function is calculated. Results are verified by an experimental setup for a combined shape and deformation measurement.
ABSTRACT
OBJECTIVE: To improve the accuracy and speed of diagnosis of an ectopic tubal pregnancy by means of blood flow analysis in the tubal arteries. We hypothesized that invasion of the trophoblast increases blood flow in the tubal artery involved in ectopic pregnancy. METHODS: In 394 patients, using an endovaginal triplex color Doppler ultrasonography system, we performed qualitative blood flow analysis in the tubal arteries on both sides. The percentage of the between-side difference in tubal blood flow was calculated. RESULTS: There was an increase in tubal blood flow on the ectopic pregnancy side, and the mean between-side difference in tubal blood flow was 20.45% in the ectopic pregnancy group. In the control groups, the between-side difference was 2.95% (t = 21.5, P < .00001). Using a cutoff point of 8% for the percentage of the between-side difference in tubal blood flow, the method had a sensitivity of 85% and a specificity of 96% for diagnosing an ectopic pregnancy. The percentage of the between-side difference in tubal blood flow was independent of gestational age (Pearson correlation coefficient 0.081). CONCLUSION: The advantages of this new method for diagnosing tubal pregnancy are early detection, noninvasivity, and immediate results.
