Cunkou is the usual region selected to take pulse. Cunkou, also known as "qikou" (opening of qi) or "maikou" (opening of pulse), refers to pulsation of radial artery on the wrist.

Cunkou is located on the pulsation of the lung meridian where qi and blood in the lung meridian flows by. Besides, qi and blood from all viscera circulates through the lung and converges over cunkou. The lung meridian starts from the middle energizer and converges with the spleen meridian. Since the spleen and the stomach are the sources of qi and blood and function as postnatal base of life, cunkou can reflect the conditions of the gastric qi. On the other hand, the lung meridian is the meridian from where all the other meridians begin and end their circulation, because the circulation of qi and blood in all the twelve meridians starts from and ends at the lung meridian, finally converging over cunkou. That is why cunkou can reflect the conditions of all viscera, qi, blood and meridians in the body.?

Pulse over cunkou is divided into three parts: cun, guan and chi. The part slightly below the styloid process of radius is guan pulse, the part anterior the guan pulse is the cun pulse, and the part posterior the guan pulse is the chi pulse. Both hands have three divisions of pulse, i.e. cun pulse, guan pulse and chi pulse. So altogether there are six divisions of pulse. Cunkou can reflect the conditions of all viscera, qi, blood and meridians in the body.

Clinically the correspondence of cunkou pulse and the viscera is decided according to the description in Neijing (Canon of Medicine), that is the upper pulse (cun pulse) corresponds to the upper part of the body and the lower pulse (chi pulse) corresponds to the lower part of the body:

The left cun pulse and the corresponding viscera: the heart and Danzhong (CV17) (the part between the breasts).

The right curt pulse and the corresponding viscera: the lung and the thorax.

The left guan pulse and the corresponding viscera: the liver and the gallbladder.

The right guan pulse and the corresponding viscera: the spleen and the stomach.

The chi pulse and the corresponding viscera: the kidney and the lower abdomen.

The right chi pulse and the corresponding viscera: the kidney and the lower abdomen.

Such a theory about the relationship between the cunkou pulse and the corresponding viscera is significant in clinical diagnosis. However, the application should be flexible and based on the synthetic analysis of the data obtained from the four diagnostic methods.