Bilateral Hemianopsia Due to Pituitary Adenoma

Author: V. Dimov, M.D.
Reviewer: S. Randhawa, M.D.

A 61-year-old Caucasian male (CM) had problems with his vision while driving and was bothered by the light. These complaints started gradually several months ago. He saw a local eye doctor who found abnormal visual fields and referred him to endocrinology. An MRI was done.

The patient also complains of decreased libido and impotence. He has history of infertility.

Past medical history (PMH)

Nonsignificant.

Family medical history (FMH)

No history of hypercalcemia, pituitary tumor, or nephrolithiasis.

Physical examination

Vital signs: 172/105-70-97 (Oral)-18-97 kg.
HEENT: Visual field defects, bilateral hemianopsia.
No diplopia, no cranial nerve palsy, symmetric pupils. Normal light reflex, no coarse facial features, no acne or moon face. Thyroid is normal size.
CVS: normal
Chest: normal
Abd: soft, NT, ND.
Ext: no c/c/e.
Neuro: no focal neurological deficit apart from bilateral hemianopsia.
Skin normal.
No gynecomastia or breast discharge.
Testicles: normal, about 15 ml bilaterally.

What is the most likely diagnosis?

Pituitary tumor compressing the optic chiasm.

What tests would you do?

MRI head.
TSH, T3, T4, prolactin, free cortisol.

Laboratory results

TSH 0.440
T3 68 (range 94-170)
Free T4 0.5 (range 0.7-1.8)
Prolactin 7.5 (range 2-14)

What happened?

The MRI of the head showed a large sellar mass with superior extension measuring about 3.5 x 2.5 x 2.5 cm. There was no evidence of cavernous sinus invasion.

What happened next?

The patient has a large sellar mass with superior extension pressing on optic chiasm suggestive of nonfunctional pituitary macroadenoma. Bitemopral visual field defect is an indication for surgical decompression. Labs are suggestive of partial central hypothyroidism.

The patient had a random cortisol of 17.1 ug/dL which indicated normal HPA axis. An ACTH stimulation test was ordered. Synthroid 75 mcg qam was started.

The patient was scheduled for transphenoidal pituitary surgery.

Final diagnosis

Pituitary macroadenoma.

References

Pituitary dosorders. Amir Hamrahian, MD. The Cleveland Clinic.
Pituitary Tumors. eMedicine.


The left optic nerve, optic tracts and chiasm. Image source: Gray's Anatomy 1918, public domain.


Paris as seen with bitemporal hemianopsia. Wikipedia.

Published: 04/11/2006
Updated: 08/05/2009