Interpretation and textual research on six new tongue manifestations

At present, some new tongue manifestations with distinct characteristics and high clinical value have not yet gained widespread consensus, which is unfavorable to their research and promotion. This paper representatively explores four types of tongue texture manifestations (liver gall line, bulging vein tongue, concave tip tongue, convex surface tongue) and two types of tongue coating manifestations (cracked tongue coating, white saliva line) among them. It is found that the liver gall line manifests as dark stagnation of various forms on the tongue surface, indicating liver qi stagnation and blood stasis as well as heat-toxin accumulation; the bulging vein tongue is characterized by clearly raised blood vessels on the tongue surface, suggesting blood stasis due to yang deficiency or cold congelation; the concave tip tongue is characterized by a depressed tip, indicating an abnormal tongue frenulum or malnutrition of heart, lung, and kidney; the convex surface tongue features a broad and thick tongue body with an overall "convex" shape, which is observed in healthy individuals or suggests qi movement disorder and spleen and stomach stagnation; the cracked tongue coating is characterized by cracks only on the tongue coating, indicating qi deficiency with disordered fluid or yin consumption due to intense heat; the white saliva line presents as strip-like white foam bands on the tongue margin, suggesting liver qi stagnation and dampness stagnancy due to spleen deficiency. No consensus exists regarding issues such as naming and description, reflecting the necessity of expanding and standardizing the theory of tongue diagnosis. This paper aims to emphasize the value and standardization of such new tongue manifestations, enrich the theoretical system of tongue diagnosis in traditional Chinese medicine, and provide novel insights and reference basis for clinical syndrome differentiation.