Figure 1.

Scintigraphy showing a left inferior parathyroid adenoma located just beyond the thyroid left lobe shape, and in anterior planes at SPECT examination. A = sequential acquisition of a set of ^99mTc-sestamibi images, lasting 5 minutes each. B = ^99mTc-pertechenetate thyroid image. C = subtraction image showing a left inferior solitary parathyroid adenoma. D = Sestamibi SPECT images (left = axial; middle = sagittal; right = coronal) reconstructed by Butterworth filter with sub-optimal parameters (cut-off = 0.40, order = 7); E = Sestamibi SPECT images (left = axial; middle = sagittal; right = coronal) reconstructed by Butterworth filter with optimal parameters (cut-off = 0.60, order = 7) depicting a left inferior parathyroid adenoma located in anterior neck planes.