What Haller index value is used as a threshold for significant Pectus excavatum on CT?

What Haller index value is used as a threshold for significant Pectus excavatum on CT?

• A. 3.2 or greater
• B. 2.0 or greater
• C. 1.5 or greater
• D. 4.5 or greater

Answer: (A)

The Haller index on CT is used to quantify how severe pectus excavatum is by comparing the chest’s width to its depth. It’s calculated as the transverse (inner) width of the chest divided by the anteroposterior depth at the level of maximal sternal depression. A normal chest has a lower ratio, while more severe deformities push this ratio higher because the sternum is sunken and the AP depth decreases. A threshold around 3.2 or greater is used to designate a significant deformity on CT. This cut-off reflects the point at which the chest wall mismatch tends to be clinically meaningful and consideration for surgical repair is warranted. Values below this are generally not regarded as significant, whereas values at or above this threshold indicate substantial deformity. The other numbers don’t fit the typical range used to define significant pectus excavatum: they are either well within normal variation or represent far less common cutoffs or extreme deformity levels that aren’t the standard threshold for signaling significance.

The Haller index on CT is used to quantify how severe pectus excavatum is by comparing the chest’s width to its depth. It’s calculated as the transverse (inner) width of the chest divided by the anteroposterior depth at the level of maximal sternal depression. A normal chest has a lower ratio, while more severe deformities push this ratio higher because the sternum is sunken and the AP depth decreases.

A threshold around 3.2 or greater is used to designate a significant deformity on CT. This cut-off reflects the point at which the chest wall mismatch tends to be clinically meaningful and consideration for surgical repair is warranted. Values below this are generally not regarded as significant, whereas values at or above this threshold indicate substantial deformity.

The other numbers don’t fit the typical range used to define significant pectus excavatum: they are either well within normal variation or represent far less common cutoffs or extreme deformity levels that aren’t the standard threshold for signaling significance.