|
|
 |
|
|
|
|
|
A 44-year-old woman with a 3-month history of bilateral, painless visual loss in the absence of other symptoms
Digital Journal of Ophthalmology 2012
Volume 18, Number 4
December 31, 2012
DOI: 10.5693/djo.03.2012.12.001
|
Printer Friendly
Download PDF |
|
|
Emily Shao, MBBS, BSC | Department of Ophthalmology, Chelsea and Westminster Hospital, London, UK Kevin Gallagher, BMBCh | Department of Ophthalmology, Chelsea and Westminster Hospital, London, UK Nabeel Malik, MBBS, FRCOPHTH | Department of Ophthalmology, Chelsea and Westminster Hospital, London, UK
|
|
|
| Diagnosis and Discussion | On presentation the patient had a 3-month history of visual loss, optic atrophy, and optic disc swelling. She did not have any symptoms or signs of raised intracranial pressure, or symptoms suggestive of demyelination or infection. CT scan of the head showed an intracranial mass. She was diagnosed with FKS, a rare neurological syndrome first described by Foster Kennedy in 1911.(1) Found in less than 1% of patients with intracranial tumors, the pathogenesis of FKS is still debated.(3) It was postulated to be caused by direct tumor compression, resulting in optic atrophy in one eye with raised intracranial pressure causing papilledema in the contralateral eye; however, bilateral optic nerve compression has been found subsequently in 33% cases, with only 22% satisfying Kennedy’s original hypothesis.(4) The clinical course of FKS is frequently insidious in nature. Headache suggestive of raised intracranial pressure (ICP) may not be present, making early diagnosis difficult.(5)
FKS may present with a relative afferent pupillary defect early on if one optic nerve is predominantly affected. Chronic papilledema may lead to nerve fiber atrophy, a degree of which may already have existed in our patient, which would explain the absence of relative afferent pupillary defect on examination. As in any cause of optic nerve dysfunction, reduced color vision is an early feature. Visual field defects, including a central scotoma, are typically present. In patients presenting with decreased visual acuity, testing of color vision and pupillary reflexes should be performed in addition to fundus examination. The clinical signs of FKS may be readily apparent in cases of gross optic disc swelling or pallor; however, optic disc pallor may be extremely subtle and easily missed.
Poorly understood, with a currently debated pathogenesis and often insidious onset, FKS remains a diagnostic challenge. Early diagnosis, with subsequent surgical resection may prevent further visual deterioration and may allow some recovery of vision in these patients.(6) Disease awareness with early intracranial imaging and surgery is necessary to minimize the disabling sequelae of FKS. | |
|
|
|
|
|
|
Welcome, please sign in 
