The anatomy of parathyroid hyperplasia

Parathyroid hyperplasia aids the surgeon in studying parathyroid anatomy for several reasons: (a) Nature magnifies the glands in hyperplasia; (b) there is a strong clinical imperative to find all glands; (c) histologic controls help guide the dissections; and (d) postoperative clinical and laboratory responses help determine the presence of supernumerary glands. In this study of parathyroid hyperplasia we found four glands in each of 34 patients (136 glands total--37 operations). Six patients (18%) had parathyroid glands totally covered by thyroid tissue, five patients (15%) had mediastinal glands, one patient (3%) had a retroesophageal gland, and one (3%) had a "kissing pair." In addition, after four-gland parathyroidectomy, three patients gave evidence of functioning supernumerary glands (9%). Abnormalities in parathyroid anatomy occurred in almost half (47%) of these patients with parathyroid hyperplasia.