Does the use of recombinant TSH in preparation for I-131 scintigraphy scan affect hearing function?

OBJECTIVE

The objective of this study was to examine the effect of hypothyroidism on hearing function in patients surgically treated for differentiated thyroid cancer and subsequently experienced hypothyroidism during preparation for follow up I-131 scintigraphy scan by either recombinant human thyroid stimulating hormone (rhTSH) treatment or thyroid hormone withdrawal (THW).

METHODS

A total of 55 patients undergoing I-131 scintigraphy scan following surgeries for differentiated thyroid cancer were included in the study, including 25 patients prepared by administration of recombinant TSH (rhTSH Group) and 30 patients by thyroid hormone withdrawal (THW Group).

RESULTS

Air conduction thresholds at 1, 2 and 4 kHz for both ears were higher during hypothyroid period than during euthyroid period for patients in the THW group (p < 0.05) but not for patients in the rhTSH group.

CONCLUSION

Sensorineural hearing loss was detected, especially at low frequencies, in patients with DTC after surgical treatment whose hormone replacement therapy was withdrawn but not in those receiving rhTSH. It is therefore preferred to use rhTSH when preparing for I-131 scintigraphy scan in patients at risk for hearing loss.