BONE-SCINTIGRAPHY EQUIPPED WITH A PINHOLE COLLIMATOR FOR DIAGNOSIS OFAVASCULAR NECROSIS OF THE FEMORAL-HEAD

The objective was to compare the sensitivities for diagnosis of avascu lar necrosis of the femoral head of bone scintigraphy equipped with a pinhole collimator and with an high resolution parallel collimator, Bo ne scintigraphy equipped with a pinhole collimator and with an high re solution parallel collimator were performed in 16 patients with bilate ral (n=7) or unilateral (n=9) avascular necrosis of the femoral head. Bone scintigraphy equipped with a pinhole collimator documented a phot openic defect in 78.3% of the necrotic hips, while bone scintigraphy e quipped with an high resolution parallel collimator documented a defec t in 47.8%. There was no false-positive diagnosis of avascular necrosi s of the femoral head on either bone scintigraphy equipped with a pinh ole or with an high resolution parallel collimator. In conclusion, bon e scintigraphy equipped with a pinhole collimator has a greater sensit ivity for diagnosis of avascular necrosis of the femoral head than bon e scintigraphy equipped with an high resolution parallel collimator.