Visual outcome of surgically managed pituitary adenomas followed-up at the Yaoundé Central Hospital

Pituitary adenomas are benign brain tumours arising from the adenohypophysis; representing 10-15% of all intra-cranial tumours. Despite improved management, they are still related to high morbidity. Visual impairment is a common presentation and visual field defects representing 37-96%. We aimed at describing the clinical presentation of operated patients and their visual outcome.

We conducted a cross-sectional study for 6 months at the Yaoundé Central Hospital's Neurosurgery, Endocrinology and Ophthalmology departments. We included all patients with histopathological confirmation, having pre-operative visual assessment and operated from January 2010 to June 2016.

Twenty-five participants (50 eyes) were enrolled. Three subtypes of pituitary adenomas were identified: Non-functional pituitary adenomas (64%) > Somatotropinomas (20%) > Prolactinomas (16%). All cases were macroadenomas. The median duration of symptoms was 14 months. All participants presented with vision impairment and 80% with headaches. Craniotomy was used in 88% of cases. The temporal hemifield was the most quantitatively affected; 76% of eyes presented with visual acuity (VA) < 6/12 and 24% of eyes a visual acuity ≥6/12. Thirty percent of eyes presented with optic atrophy; cranial nerve III palsy was the most observed. The Mean deviation (MD), an automated visual field index, improved though non-significant and 16% of eyes had a normal visual field printout after surgery. Left eye mean deviation improved significantly (p = 0.04). After surgery, there was a mild improvement of VA with 62% of eyes having a VA< 6/12 and 38% a VA ≥6/12. There was no ophthalmoplaegia after surgery. Long delay before diagnosis significantly jeopardizes pre-operative and post-operative visual acuity (r = 0.5; p = 0.01).

Quantitative vision parameters comparison are suggestive of a potential improvement of vision. This conclusion will be better ascertained on a large-scale sample size. Long delay before diagnosis is associated to poor visual outcome.