Funnel chest is very easy to diagnose clinically, and the deformity is readily apparent. However, it is more difficult to determine the severity of the funnel chest, and there are many clinical methods of describing it. 1.Body surface corrugation domain map is a method to objectively describe the deformity It uses light source and lattice projection method to take pictures of the corrugated contour image of the depressed part of the chest wall, and based on the interval and number of corrugated contour lines, the volume of the depressed part is calculated by digital converter into the electronic computer to determine the severity of the funnel deformity, and the effect of surgical treatment can be evaluated. 2.Funnel Index (FI) is another method to express the deformity. a. longitudinal diameter of the funnel chest depression; b. transverse diameter of the depression; c. depth of the depression; A. length of the sternum; B. transverse diameter of the thorax; C. shortest distance from the angle of the pectoral muscle to the vertebrae The criteria for determining the degree of funnel chest depression are: severe: FI>0.3, moderate 0.3>FI>0.2, mild: FI<0.2 3.water injection in the funnel to measure the water volume Make the patient lie on his back, inject water in the funnel and then The water volume can also be measured to understand the severity of the funnel chest, and the volume of water in severe funnel chest can reach about 200ml. The volume of the sunken part of the funnel chest can be easily measured by filling the funnel chest with playdough, shaping it and then removing it and immersing it in water. X-ray examination can see that the posterior part of the rib cage is flat and the anterior part is sharply tilted downward in front, the heart shadow is mostly displaced to the left side of the chest cavity, there is an obvious radiolucent area in the middle of the heart shadow, the right heart edge often overlaps with the spine, individual patients with severe heart shadow can be completely located in the left chest cavity, older patients have more scoliosis of the spine. Lateral chest radiographs can show that the sternal body is obviously bent backward, and some of the lower sternum can reach the anterior edge of the spine Posterior anterior radiographs: the transparent area in the heart shadow of funnel chest Chest CT films can more clearly show the severity of the thoracic deformity and the degree of heart compression and displacement. The ECG may show inverted or bidirectional P waves in V1 and may also have right bundle branch conduction block. Cardiac catheterization may be traced to diastolic slopes and plateaus, the same as seen in constrictive pericarditis, and cardiovascular angiography shows right heart compressional malformation and right ventricular outflow tract obstruction. In most cases, the sternum begins at the level of the second or third costal cartilage and moves backward to a point slightly above the glabella as the lowest point, then returns forward to form a boat-like deformity. On both sides or laterally, the deformation is concave inward, forming the two walls of the funnel chest. In funnel chest, the rib alignment slope is larger than normal, and the ribs are depressed sharply from the top to the bottom, making the front and back closer, and in severe cases, the deepest depression of the sternum can reach the spinal surgery. In young patients with funnel chest, the deformity is often symmetrical, but with age, the deformity gradually becomes asymmetrical, the sternum tends to rotate to the right, the depression of the right rib cartilage tends to be deeper than the left, and the right breast development is worse than the left. The posterior thorax is mostly flat back or round back, and scoliosis gradually worsens with age; scoliosis is less likely to occur when the patient is younger, and is more pronounced after puberty. The funnel chest deformity compresses the heart and lungs, and the heart is mostly displaced to the left side of the chest. Children often present with a distinctive frail posture: forward neck, rounded cut shoulders, and a cankered abdomen. Funnel chest is most often seen in children under 15 years of age and is rarely seen in patients over 40 years of age, probably because of the compression of the heart and lungs by the funnel chest and scoliosis, which impairs respiratory and circulatory function, resulting in a shorter survival time and death before the age of 40. Mild funnel chests can be asymptomatic, while more severe deformities compress the heart and lungs, affecting respiratory and circulatory function, reducing lung capacity, increasing functional residual air volume, and reducing activity tolerance. Young children often have recurrent respiratory infections with cough and fever and are often diagnosed with bronchitis or bronchial wheeze. Young children have fewer circulatory symptoms, while older ones can present with dyspnea, rapid pulse, palpitations, and even pain in the precordial region after activity, mainly because the heart is compressed, the cardiac blood output cannot meet the needs during exercise, and the myocardium is hypoxic, thus causing pain. Some patients may also have arrhythmias and systolic murmurs. Funnel chest is sometimes combined with pulmonary hypoplasia, Marfan syndrome, and asthma, and the combined presence of these diseases often becomes an intolerable deformity for the patient, often requiring early surgical correction.