The Results of Transsphenoidal Operation in Acromegalic Patients

Abstract

Twenty-three patients with active acromegaly were subjected to transsphenoidal microsurgery, during the past two years. These patients were preoperatively classified into 14 TRH responders, 5 LH-RH responders and 2 non-responders. L-DOPA and bromocryptine effectively reduced serum growth hormone (GH) levels in most of TRH responders but in none of LH-RH responders and non-responders. Pre- and post-operative basal serum GH levels ranged between 9.0 and 484.0 ng/ml, 3.6 and 80.6 ng/ml, respectively. In 19 patients who could be followed up longer than 3 months, post-operative serum GH concentrations were below 10 ng/ml in 14 patients, but in many cases abnormal GH responses to TRH and LH-RH were still present. However, in 6 cases abnormal GH responsiveness to TRH or LH-RH was reverted to normal, preserving normal GH increase after insulin hypoglycemia. Overall results suggest that surgical success is very high when the tumor is localized in the sella. Autonomy of GH secretion by the surgical specimen from 4 patients was found to be continuing a month later by the culture method and rich secreting granules were confirmed in the cytoplasm. These results suggest that the primary lesion in acromegaly would be in the pituitary gland, being partly influenced by hypothalamic factors. Revertion of abnormal GH responsiveness to non-specific releasing hormone is a good indicator of the completeness of the operation and these provocative tests are very useful for postoperative follow-up study in acromegaly, L-DOPA or bromocryptine treatment should be applied to cases with insufficient operative results. © 1978, The Japan Neurosurgical Society. All rights reserved.