Effect of polar ligations upon the remaining lobe of thyroid gland after the removal of one lobe.

Abstract

A review of the laboratory records of the Class in Surgery, S. 101-102 (1921-1924) shows 63 operations upon the thyroid with data incomplete in 30 and complete in 32. Of the latter, 16 were superior thyroid ligations following hemithyroidectomies, 3 inferior thyroid ligations following hemithyroidectomies, 11 bipolar ligations combined with the removal of one lobe, one bipolar ligation without thyroidectomy and one excision of adventitia from a portion of the carotid artery. It is believed that a superior polar ligation in a hemithyroidectomized dog, in a measure, corresponds with the ligation of the two superior poles in a human hyperplastic goitre. The experimental bipolar ligation may be analogous to the ligation of all four poles in the human gland. The changes in the thyroid remnants under these conditions are thought to be suggestive of the findings in selected human ligations and thyroidectomies.

Of the unipolar ligations less than 20 per cent remained normal while more than 80 per cent revealed hyperplasia of the interstitial epithelial cells or adenomatosis. Of the latter, approximately one-third showed hemorrhage into the thyroid capsule or into the gland or congestion or replacement fibrosis to some degree. After bipolar ligations, the residual thyroid tissue appeared hyperplastic or atrophic in abut equal numbers of instances. A few of the latter animals died suddenly within two days after operation.

Parathyroids appeared on section in 21 of the above 32 cases. Of these, approximately one-third remained normal while two-thirds showed congestion or replacement fibrosis. Halsted's observation of degenerative changes in the parathyroids following inferior polar ligations appeared in part borne out in the few instances at hand. In one instance colloid was noted with epithelial cells and acini closely resembling thyroid tissue.