|
|
 |
|
|
|
|
|
A 71-year-old woman with decreased vision, nyctalopia, and peripheral vision loss
Digital Journal of Ophthalmology 2016
Volume 22, Number 4
December 31, 2016
DOI: 10.5693/djo.02.2016.06.001
|
Printer Friendly
Download PDF |
|
|
Ravi Parikh, MD, MPH | Department of Ophthalmology and Visual Science, Yale University, New Haven, Connecticut Miguel A. Materin, MD | Department of Ophthalmology and Visual Science, Yale University, New Haven, Connecticut; Smilow Hospital at Yale New Haven Hospital Robert Lesser MD | Eye Care Group, New Haven, Connecticut Joachim Baehring, MD, PhD | Smilow Hospital at Yale New Haven Hospital; Department of Neurology, Yale University, New Haven, Connecticut Mario Sznol, MD | Smilow Hospital at Yale New Haven Hospital; Department of Internal Medicine, Yale University, New Haven, Connecticut Jennifer A. Galvin MD | Department of Ophthalmology and Visual Science, Yale University, New Haven, Connecticut
|
|
|
| Diagnosis and Discussion | CAR and MAR are both rare paraneoplastic syndromes that can be distinguished by clinical symptoms, fundus characteristics, and electrophysiology findings. Small-cell lung cancer has been most frequently reported as the primary cancer in CAR; breast and endometrial cancers have also been reported but less frequently.(1) CAR typically presents with loss of central vision, reduced color vision, a ring scotoma, photopsias, and decreased a-wave and b-wave on ffERG.(2) MAR typically presents with rapid onset of photopsias, scotomata, decreased night vision, and variable loss of peripheral or paracentral vision.(3,4)
Our patient had positive antiretinal autoantibodies against the 46-kDa enolase protein, which is also associated with CAR; but, positive antiretinal autoantibodies are also found in 10% of healthy patients and in various autoimmune diseases.(5)
Our patient did not have any other paraneoplastic or antiretinal autoantibodies. The ffERG finding helped confirm the diagnosis of MAR. The proposed pathophysiology of MAR is due to antibodies which target the depolarizing bipolar cells.(6) In MAR, the photopic ffERG shows a decreased b-wave with a relatively normal a-wave, whereas the scotopic ffERG shows a markedly decreased b wave with decreased b/a wave ratio. In CAR, on the other hand, the photopic and scotopic ffERG shows a decreased a-wave and decreased b-wave.(7)
Both of these paraneoplastic syndromes can be treated with immunomodulation. Our patient was treated with intravenous immunoglobulin.(8) Although no large randomized trials exist, visual improvement in CAR has been reported in the majority of patients receiving corticosteroid treatment, although it has been noted that some patients with autoimmune retinopathies have improved with a combination of plasmapheresis and corticosteroid therapy.(1)
Visual loss in patients with a cancer history may be due paraneoplastic syndromes, treatment toxicity and ocular metastases. In addition to clinical evaluation, serologies and electrophysiology testing are important to establish a diagnosis. A diagnosis of a paraneoplastic disease should prompt evaluation of a patient for a primary cancer, metastatic disease, or progressing systemic cancer. | |
|
|
|
|
|
|
Welcome, please sign in 
