Inspection of tongue 望舌
The concept Inspection of tongue, is a diagnostic method by means of observing the changes of the body and coating of the tongue. It is an important part of inspection diagnosis in TCM.
Ⅰ The principle of tongue diagnosis
a. The relationship between the tongue, internal organ, meridians 脏腑经络与舌象的关系
1 the tongue is a sprout of the heart(舌为心之苗)，手少阴心经之别系舌本。望舌色可了解人体气血情况，而反映心主血脉的功能。舌体运动是否灵活自如，语言是否清晰，又反映心藏神的功能。
2 the tongue is a manifest of the spleen(舌为脾外候)，足太阴脾经连舌本、散舌下。舌苔与脾胃运化功能相应。舌象与脾主运化，化生气血功能直接有关。
3 the kidney meridian reaches both sides of the tongue and the kidney stores essence. 肾藏精，足少阴肾经挟舌本 the liver stores blood and governs tendons, the liver meridian also extends to the tongue. 肝藏血、主筋，经脉络舌本 the lung reaches the throat and is connected with the tongue 肺系上达咽喉，与舌根相连等等
b.the relationship between the tongue,qi,blood and fluid气血津液与舌象的关系
The tongue depends on qi and blood to nourish and body fluid to moisten.(舌血脉丰富，有赖气血的濡养和津液的滋润) So examination of the tongue can reveal the states of the viscera, qi, blood, and the body fluid.
c the principle of correspondence of the tongue to the viscera
舌诊脏腑部位分属图
舌尖——心肺病变， 心火上炎多舌尖红赤；
舌中——脾胃病变，脾胃运化失常，湿浊、 痰饮、食滞停积中焦，见舌苔厚腻
舌根——肾的病变，久病及肾， 肾精不足可见舌根苔剥
两侧——肝胆病变。肝胆气滞血瘀， 常见舌两侧紫色斑点或舌边青紫。
d the constitution of tongue in modern medicine 舌的组织结构 舌是由横纹肌组成的肌性器官。 具有协助咀嚼，吞咽，感受味觉和辅助发音 等功能。
舌面覆盖一层半透明的粘膜，粘膜皱折 成许多细小突起，称舌乳头。 舌乳头分为： 丝状乳头 蕈状乳头 轮廓乳头 叶状乳头
丝状乳头： ◆形如软刺，呈角化树状。 ◆脱落细胞、食物残渣、细菌、粘液等 填充其间隙，形成舌苔。
蕈状乳头： ◆上部圆钝如球，根部细小。 ◆主要分布于舌尖和舌边。 ◆透过上皮隐约可见乳头内的毛细血管， 肉眼所见如一个小红点。 ◆蕈状乳头的形态、色泽改变，是舌体 变化的主要因素。
Ⅱ The methods and attention points of tongue diagnosis
a body position and posture of inspection of tongue 望舌的体位和伸舌姿势 The patient is asked to sit down or lie in supination.患者取坐位或仰卧位 The tongue is protruded naturally and the tip of the tongue is kept slightly downwards. 伸舌自然，舌体放松，舌面平展，舌尖略向下；尽量张口使舌体充分暴露。
b the sequence of inspection of tongue诊舌的方法 1 先看舌尖，再舌中、舌侧，最后看舌根部。 2 先看舌体的色质，再看舌苔。 3 若伸舌时间过久， 舌体易随血管变形而色泽变化。 4 如判断不清， 可令病人休息３～５分钟后重复望舌。 5 其他诊察方法：刮舌验苔法。 刮之不脱或刮而留污质，为里有实邪； 刮之易去，舌体明净光滑则多属虚证。
To begin from the tip of the tongue, then middle and margin . The inspection begins with the tongue body first and then moves to the tongue coating. The inspection should be complete and quick.