IMAGING OF HYPERPARATHYROIDISM - US, CT, MRI AND MIBI SCINTIGRAPHY

Hyperparathyroidism is a rare condition although recently the incidenc e has increased, particularly the asymptomatic form, as a result of ro utine serum calcium measurements. A definitive diagnosis can be made u sing modern bio-assays giving direct measurements of parathormone (PTH ), Various methods are currently available for pre-operative localisat ion of pathological parathyroid glands. Ultrasound is sufficient prior to the initial surgery. However, if primary surgical exploration fail s to localise the parathyroid glands then the surgeon faces a more com plex problem and requires precise localisation prior to repeat surgery to reduce operating time and risk. No radiological method is availabl e to localise pathological glands in 100% of cases. The surgeon is usu ally satisfied when two different methods are positive and in concorda nce. The non-invasive methods such as ultrasound, CT, MRI and scintigr aphy are initially performed and if the result remains equivocal then more invasive methods such as arterial or venous sampling are undertak en. Our preliminary results in secondary hyperparathyroidism, before r epeat surgery, indicate that associated and complementary tests, morph ological and functional, MRI (fat-sat, T1, gadolinium) and MIBI scinti graphy, have greater efficacy.