The deformity is already visible in the first year of life. The patient’s breathing pattern needs careful observation. If the sternum moves inwards when breathing in, this is reverse or paradoxical respiration. This is linked to unfavourable progress in the case. Monitoring is performed through biannual visits, which may be increased should the patient present more significant respiratory problems and need to be hospitalised. It is not necessary to perform complementary explorations before the age of four (approximately) as these do not add anything.
This allows sternal sinking to be observed laterally and the AP and transverse diameters to be measured. A metallic or barium marker may be placed in the depths of the funnel. This also reveals related deformities, such as scoliosis, hemivertebrae, fused ribs, etc.
Patients are given a computed tomography (CT Scan) of the chest. Only a few slices of the funnel are requested unless the deformity is more complex, in which case a helical CAT Scan may be used.
Conventional slices to the maximum depth of the funnel allow the degree of Pectus Excavatum to be appreciated, based on calculation of the Heller Index. This index is obtained by dividing the transverse axis (horizontal distance across the interior of the chest cavity) by the anteroposterior axis (shortest distance between vertebrae and sternum) and it correlates with the surgical indicators when it is equal to or greater than 3.25.
Cardiac and pulmonary assessment may be performed using:
In many cases, patient monitoring means repeating some or all of the tests to assess progress in stabilisation or worsening and to establish the indicators more accurately.