title: Parathyroid scintigraphy during hypocalcaemia in primary hyperparathyroidism.
abstract: BACKGROUND
  Minimally invasive parathyroid surgery in patients with primary hyperparathyroidism (PHPT) demands high imaging accuracy. By increasing blood flow to the parathyroid adenoma before injection of a perfusion marker, we intended to improve the parathyroid scintigraphy. We have named the technique stimulated parathyroid scintigraphy (SPS).
  
  
  METHODS
  Twenty minutes after injection of 100 MBq (99m)Tc-pertechnetate a thyroid scintigram was performed in 25 patients with PHPT. During the thyroid scintigraphy sodium citrate was infused which lowered plasma calcium by a mean of 14 +/- 1.3%. Then 700 MBq (99m)Tc-sestamibi was injected and another scintigram of the neck was obtained. Perchlorate was given at the end of the sestamibi scintigram to increase the wash-out of (99m)Tc-pertechnetate from the thyroid gland, and after 2 h a delayed scintigram was obtained. A subtraction of the thyroid scintigram from the initial sestamibi scintigram was performed. The results of SPS and a conventional (99m)Tc-sestamibi dual-phase parathyroid scintigraphy were compared with the operative findings. In nine patients the parathyroid adenoma was also localized with ultrasound and the flow pattern before and after citrate infusion was visualized with Doppler technique.
  
  
  RESULTS
  Eighty-eight per cent of the adenomas were localized correctly with the SPS technique compared with 62% at the conventional parathyroid scintigraphy. Tissue perfusion of the nine adenomas increased after citrate infusion.
  
  
  CONCLUSIONS
  SPS has a high accuracy and it is easy to perform. If only subtraction SPS is performed the whole examination can be completed within an hour, which is acceptable for same day surgery.
authors.affiliation: Department of Clinical Physiology and Nuclear Medicine, Herlev University Hospital, Denmark.
authors.forename: Christina G
authors.initials: CG
authors.lastname: Øgard
authors.forename: Henrik
authors.initials: H
authors.lastname: Vestergaard
authors.forename: Jørn B
authors.initials: JB
authors.lastname: Thomsen
authors.forename: Henrik
authors.initials: H
authors.lastname: Jakobsen
authors.forename: Thomas
authors.initials: T
authors.lastname: Almdal
authors.forename: Steen L
authors.initials: SL
authors.lastname: Nielsen
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging*; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D006961:Hyperparathyroidism / Q000000981:diagnostic imaging*; D006996:Hypocalcemia / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D010282:Parathyroid Neoplasms / Q000000981:diagnostic imaging*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D013670:Sodium Pertechnetate Tc 99m; D014463:Ultrasonography
chemical_list: D019275:Radiopharmaceuticals; D013670:Sodium Pertechnetate Tc 99m