Ectopie de la parathyroïde objectivée par la scintigraphie au MIBI-Tc 99m. À propos de deux cas. Expérience du service de médecine nucléaire – CHU Ibn Sina-Rabat

Abstract

The presence of a parathyroid gland in ectopic position is the most common cause of persistent hyperparathyroidism. Detection is a source of topographic diagnostic difficulties especially for purely morphological examinations. To this end, the MIBI-Tc 99m scintigraphy acts as a means of functional imaging to determine the topography of the ectopic parathyroid gland at a favorable dosimetry cost. In our work, undertaken in the nuclear medicine department of Ibn-Sina hospital center university hospital of Rabat-Salé, the MIBI-Tc 99m scan double-phase is of great interest to the extent that it could assert the existence of an ectopic mediastinal parathyroid gland in a patient with persistent hyperparathyroidism after a subtotal parathyroidectomy with recurrent primary hyperparathyroidism with low phosphorus and a cervical ectopic but supraclavicular focus in another patient of 43 years with persistent hyperparathyroidism due to secondary hyperparathyroidism in chronic renal failure. This allowed the orientation of the surgical resection of the ectopic gland. Follow-up was marked by a clear clinical and biological improvement. The MIBI-99m Tc scan seems to offer the highest diagnostic efficacy for the assessment of persistent hyperparathyroidism, a fortiori, when it comes to localize multiple and/or ectopic parathyroid glands.