Endocrine Abstracts

Introduction: Somatotropin macroadenomas are associated with a considerable risk of ophthalmological impairment. The aim of our study was to determine the prevalence of ophthalmological complications and their associated factors in patients with acromegaly.

Methods: We conducted a retrospective study including 28 patients with somatotropin adenomas and followed in the endocrinology department of Charles Nicolle Hospital. Clinical, biochemical and imaging data were collected. Ophthalmological findings (visual acuity, visual field and fundus) were also recorded.

Results: There were 17 women and 11 men. The mean age at the diagnosis of acromegaly was 45.9 ± 13.9 years. Ophthalmological examination showed reduced visual acuity (RVA), visual field defects and papilledema in 25, 36 and 22% of cases, respectively. GH nadir during oral glucose tolerance test (P< 10-3) and the tumor size (P=0.001) were significantly higher in patients with suffering from RVA. ACTH and cortisol levels were on the contrary lower among these patients (P=0.001). Aggressive tumors (P=0.038), optic chiasm invasion (P< 10-3) and corticotroph deficiency (P=0.022) were associated to an increased risk of vision loss. Visual acuity was negatively correlated with tumor size (r=-0.727; P< 10-3) and the number of pituitary deficiencies (r=-0.621; P=0.005). However, age, sex, cavernous or sphenoidal sinus invasion did not have a significant association with RVA.

Conclusion: Optic pathway compression, caused by somatotropin macroadenomas exposes to a considerable risk of vision loss. Tumor size, aggressive tumors, optic chiasm invasion, GH nadir level and the number of pituitary deficiencies help to predict that risk.