Thyroid function following partial thyroidectomy

Abstract

The main objective of this investigation was to establish the incidence of hypothyroidism and recurrent goitre following partial thyroidectomy. Accurate measurements of the thyroid remnants and resected specimens have been made in all cases. The postoperative thyroid status has been assessed clinically and also biochemica!ly by serum fhyroxine as iodine, T, resin uptake, free thyroxine index and thyroid-stimulating hormone estimations. Serum calcium and phosphorus have also been measured and the necessary histological material reviewed.Postoperative hypothyroidism occurred in approximately I 1 per cent of previously toxic and 6.5 per cent of non-toxic patients, becoming evident in most cases within a year of operation. The T , resin uptake measurement follo wing operation in this and previous series suggests that in many patients there is a compensation process which is maintained by increased secretion of thyroid-stimulating hormone. N o evidence has been adduced that patients who show this compensation mechanism are, as some have suggested, in a state of 'subclinical hypothyroidism' or that they become overtly hypothyroid later.In this series hypothyroidism was more closely related to small remnant size than the presence of lymphadenoid change. A significantly higher proportion of patients with small thyroid remnants became hypothyroid in both toxic and non-toxic groups. Remnants of about 8-16 ml 'cuboid' volume (roughly 8-16 g by weight) have seemed reasonable for our patients.

Hypothyroidism Following Hemithyroidectomy

“…Risk factors for hypothyroidism in these studies have variously been attributed to the presence of anti-TPO antibodies, thyroiditis, multinodular goiter, preoperative thyrotoxicosis, and thyroid remnant Ͻ6 mLs. 1,[3][4][5][6] Our study concurs that histologic evidence of thyroiditis and thyroid antibodies increases the risk for postoperative hypothyroidism. They are evidence of an inflammatory process within the thyroid that can lead to progressive tissue destruction.…”

Thyroid function after resection for non-toxic goitre with special reference to thyroid lymphocytic aggregation and circulating thyroid autoantibodies

“…Hypofunction did not develop in any of the patients during the 3 years of follow-up. Nor were Griffiths et al (1974) able to confirm any correlation between lymphocytic infiltration and thyroid impairment.…”

“…The frequency of hypothyroidism after surgical treatment for sporadic non-toxic goitre varies from 0-8% in different studies (Heimann 1962;Nielsen et al 1963;Young & Macleod 1972;Solem et al 1973;Griffiths et al 1974;Van Welsum et al 1976;Geerdsen & Hee 1982). Blichert-Toft et al (1979) demonstrated that overt hypothyroidism defined clinically and by lowered serum FT4I took place in 2%, although the TSH level was significantly raised in 16% post-operatively.…”

Elevação de hormônio tireoestimulante (TSH) após as lobectomias: incidência e fatores associados

“…Piper encontrou relação entre infiltrado linfocitário e hipotireoidismo pós lobectomia, porém essa relação era idade dependente 13 . Outros autores, contudo, não encontraram essa relação 3,4,11,[14][15][16] . O volume de glândula remanescente tem sido classicamente estudado como indicador de hipotireoidismo pós-operatório, em pacientes submetidos à tireoidectomia por bócio tóxico 3,[17][18][19] .…”