(2) The Clear Lead Compensating Filter System protects the patient and
reduces exposure to breasts and gonadal areas. It is used at 40 inches or 70 inches. It
is magnetic and is quick and easy to use. Clear Lead avoids graininess of aluminum
filters and eliminates burn areas. See figure 4-10.
Figure 4-10. Compensating filters.
(3) Alternate series: Include different methods of demonstrating the effects
of the curvature. In addition to the AP and PA views, left and right lateral-bending and
hyperextension-hyperflexion series are sometimes done to demonstrate the actual
range of motion to compare to degree of curvature.
(4) Measurement of scoliosis: There are two accepted methods of
measurement--the Cobb and Ferguson methods of scoliosis measurement.
(a) Cobb's method is the standard method of measurement. It is
primarily used for curvatures over 50 degrees.
(b) Ferguson method involves obtaining two images, one standard
erect AP and PA and one with the foot or hip on the convex side of the curve elevated.
It is primarily used for curvatures under 50 degrees.
b. Treatment. Treatment of scoliosis varies with the severity and involves the
use of braces and, in the severest cases, surgical insertion of spinal fixation devices.
The prototypical spinal fixation device is the venerable Harrington rod (figure 4-11).
They come in two types: distraction and compression. The hooks, by design, are
placed under the lamina or transverse processes and the device is either extended or
compressed to the desired position. Sometimes both types of rods will be used in the