Thallium isotope scintigraphy and ultrasonography: Comparative studies of localization techniques in primary hyperparathyroidism

Abstract

Controversy exists about whether preoperative localization procedures are indicated in patients with primary hyperparathyroidism before first neck exploration. Currently, thallium subtraction scintigraphy and ultrasonography are the techniques used most frequently. This paper examines prospectively the accuracy and value of these techniques in a group of 71 patients with primary hyperparathyroidism. When considering all glands, thallium scanning produced a sensitivity of 46.6 per cent with a specificity of 91.5 per cent, compared with a sensitivity of only 21.4 per cent and specificity of 94.5 per cent for ultrasonography. Accuracy rates, for all glands, were 80 per cent and 75.7 per cent respectively. Both localization procedures were consistently ineffective in localizing adenomas weighing less than 500 mg, over 80 per cent of which went undetected by both scanning modalities. While both scans produced satisfactory results in localizing adenomas weighing more than 1 g, these adenomas should not represent a challenge to an experienced endocrine surgeon and, therefore, neither localization is recommended before first neck exploration.

Surgical treatment of primary hyperparathyroidism: An institutional perspective

“…In an elegant study by Carlson and associates [7], thallium isotope scintigraphy and ultrasonography were compared in patients with HPT. The authors found that both modalities were consistently ineffective in the localization of parathyroid ade-nomas weighing <500 mg, with over 80% of the adenomas undetected by either modality.…”

99mTc-MIBI-SPECT-Nebenschilddriisen-szintigraphie zur präoperativen Lokalisation kleiner Nebenschilddrüsenadenome

“…40-60% bei einer vergleichsweise hohen Strahlenexposition (17 mSv) (1,10,26). Nur bei großen EK-Adenomen zeigt die Subtraktionsszintigraphie eine zufriedenstellende Sensitivität (1), wie aber fast alle anderen bildgebenden Verfahren auch (6). Abb.…”

“…3 Vergleich der Sensitivität der 201 TI/" m Tc-Subtraktionsszintgraphie und der " m Tc-MIBI-Szintigraphie (planar und SPECT, je nach 20' und 120' p.i.). Statistische Signifikanz beim Sensitivitätszuwachs lag bei n = nur beim Vergleich planare Bilder -3D-Darstellung (p = 0,03) vor phie mit 50% trotz der auch hier verwendeten modernen Kamera nur innerhalb der sonst üblichen Literaturergebnisse (4,6). Die EK-Adenomlokalisation mit " m Tc-MIBI führt zu einer vergleichsweise geringen Strahlenexposition von 3 mSv.…”

Thallium-Technetium Subtraction Scintigraphy of Enlarged Parathyroid Glands after Calcitonin Stimulation of Parathyroid Hormone Secretion

“…Although recognized as a useful tool in planning reoperation for primary hyper parathyroidism (pHPT) (5,12,13), its use before a primary neck exploration is controversial (6,18). Thus, a skilled parathyroid surgeon is able to identify the diseased glands in 92 to 98% of cases (19), whereas the sensitivity for the scintigraphy is only 70 to 85% (10,14,21) or, in recent studies, even lower (4,11,15,20). A number of studies have shown a decreased sensitivity of scintigraphy in detecting small (4,11,15,20,21) or hyperplastic parathyroid glands (4,11,14,15,21), and in patients with thyroid abnormality (21).…”

“…Thus, a skilled parathyroid surgeon is able to identify the diseased glands in 92 to 98% of cases (19), whereas the sensitivity for the scintigraphy is only 70 to 85% (10,14,21) or, in recent studies, even lower (4,11,15,20). A number of studies have shown a decreased sensitivity of scintigraphy in detecting small (4,11,15,20,21) or hyperplastic parathyroid glands (4,11,14,15,21), and in patients with thyroid abnormality (21). A rationale for using preoperative localizing proce dures is the potential for reducing operation time (16) and complications.…”