Reply to Dr. Yao et al.

We thank Dr. Yao et al. for their interest in our article [1]. In their letter, Dr. Yao et al. point out some problems associated with our article that they believe need to be resolved. First, they mentioned the cases excluded from our study. We excluded 61 out of 132 cases because the quality of the images was not good enough. They stated that magnification endoscopy has enough resolution for visualization of the capillary network in 100 % of cases. We regret that we were not able to visualize the microvascular pattern in all cases because of problems such as difficulties with focus, bleeding, and location of the lesions. It is true that we did have a high number of excluded cases, and we believe that technical improvements are necessary in order to obtain images of good enough quality to be eligible for our image analysis.

Secondly, we concluded that the mean caliber of the vessels in cancerous lesions was greater than that of vessels in benign gastric lesions, but Dr. Yao et al. believe this to be controversial. In fact, the caliber of microvessels in gastric cancerous lesions is irregular, so smaller microvessels are observed. We reached our conclusion based on calculation of the mean caliber of the vessels. However, we do not believe that calculation of mean caliber of the vessels is the best way to evaluate the microvascular architecture and we think further work is needed in the search for a more useful parameter for evaluation of the microvascular architecture.

Thirdly, we measured the caliber of vessels after hematoxylin and eosin staining, but they state that immunostaining is necessary for measuring the caliber of vessels. We performed immunostaining with CD34, but we did not think that this was necessary.

We appreciate the recent work of Dr. Yao et al. which has provided fine magnified images of gastric lesions [2]. We also believe that the development of sophisticated magnification techniques and precise observation of the microvascular architecture should lead to new developments in the endoscopic diagnosis of gastric diseases.

Competing interests: none

References

• 1 Ohashi A, Niwa Y, Ohmiya N. et al . Quantitative analysis of the microvascular architecture observed on magnification endoscopy in cancerous and benign gastric lesions.  Endoscopy. 2005;  37 1215-1219
• 2 Yao K, Kato M, Fujisaki J. Technique using the hemoglobin index for the gastric mucosa.  Endoscopy. 2005;  37 479-486