Long-term Effects of Transsphenoidal Hypophysectomy on Growth Hormone, Renal Function and Eyeground in Patients With Diabetic Retinopathy

Pituitary ablation was used to treat diabetic retinopathy in twelve patients. The treatment was associated with stabilization and lack of progression of visual findings in seven patients for thirty to ninety-nine months following surgery with loss of growth hormone responsiveness in three, lowering of fasting growth hormone levels in three and lowering of growth hormone reserve in one. Renal function (glomerular filtration rate and renal plasma flow) was reduced by 30 to 37 per cent within four months following surgery in those patients who showed loss of growth hormone activity. Reduced function was ameliorated with human growth hormone. Renal clearance studies indicate that loss of growth hormone may lead to increased renal arterial resistance. A beneficial effect on renal function was not observed in later observation periods. The decreased insulin requirement and increased morbidity in the posthypophysectomy state seem to be related to the loss of growth hormone.