Impaction (animals): Impaction occurs in reptiles when they consume something that they cannot digest. Common causes of impaction are rocks and sand, which might be accidentally consumed when the reptile attacks its prey.Blanch (medical): When skin is blanched, it takes on a whitish appearance as blood flow to the region is prevented. This occurs during and is the basis of the physiologic test known as diascopy.Functional constipation: Functional constipation, known as chronic idiopathic constipation (CIC), is constipation that does not have a physical (anatomical) or physiological (hormonal or other body chemistry) cause. It may have a neurological, psychological or psychosomatic cause.Thumbprint sign: In radiology, the thumbprint sign, or thumbprinting, is a radiologic sign found on a lateral C-spine radiograph that suggests the diagnosis of epiglottitis. The sign is caused by a thickened free edge of the epiglottis, which causes it to appear more radiopaque than normal, resembling the distal thumb.