Posters

Pseudo Foster - Kennedy Syndrome: diagnosis and causes

Poster Details

First Author: F.Akritidou GREECE

Co Author(s): S. Roumelis   I. Kassos   T. Papapaulidou   I. Milona   A. Karachalios   C. Karagiannidis     

Abstract Details

Purpose:

The purpose of this paper is to present a case of pseudo Foster Kennedy syndrome and to discuss the most common causes and the diagnostic process of this syndrome.

Setting:

General Hospital of Serres, Greece

Methods:

A 78-year-old man was referred to our institution, complaining of a two-week history of painless vision reduction in his right eye. On examination his visual acuity, using Snellen chart, was 1/10 in his right eye and light perception in his left eye. He had IOL PC in both his eyes after uneventful cataract surgery a couple of months ago. On fundus examination, his right optic nerve was swollen, hyperemic, with disc hemorrhage, pallor and attenuated blood vessels while his left optic nerve was completely atrophic and pale. Automated perimetry was not possible to perform due to very low visual acuity. He was on medication only for blood pressure. Complete laboratory testing, cardiological consultation, carotid doppler, orbit and cranial CT was performed. The patient did not consent to perform temporal artery biopsy.

Results:

His erythrocyte sedimentation rate (ESR) was 8, CRP was lower than 1.0 mg/L and his platelet levels within normal range. Laboratory testing for autoimmune conditions was negative. Brain and orbit CT was without pathological findings and there was no cerebral infarction. His blood pressure was well controlled under medication and echocardiography was without pathological findings. Carotid doppler revealed stenosis of both carotids. Vascular-surgical consultation was requested. Initially he was started on intravenous prednisone and continued with oral corticosteroids. The swelling of the left optic nerve partially resolved in four weeks. At eight weeks follow up his visual acuity in his right eye improved reaching 2/10 and optic nerve edema was replaced by pallor. The final diagnosis was bilateral sequential NAION which is the most common cause of pseudo-Foster Kennedy syndrome.

Conclusions:

True Foster Kennedy syndrome is very rare while Pseudo Foster Kennedy syndrome (PFK) is a diagnosis of exclusion. Most commonly PFK is due to bilateral sequential NAION, but when a suspicion arises, neuroimaging should routinely be obtained, especially if the history is vague or not typical for anterior ischemic optic neuropathy (AION). The differential diagnosis of the clinical finding of a pale optic nerve with contralateral optic nerve head edema is broad, but each case should be evaluated individually and, depending on the findings and the history, neuroimaging, laboratory workup for GGA and an assessment for increased intracranial pressure should be ordered.

Financial Disclosure:

None