Partial recovery of the visual field scotoma upon early retinal photocoagulation and the medical therapy in a preeclamptic patient

Abstract

To the Editor: Preeclampsia is a major cause of maternal and perinatal morbidity and mortality. It still accounts for 200 000 maternal deaths world-wide per year.1 We report a case of preeclampsia with branch retinal vein occlusion with corresponding visual field scotoma which partially recovered with the early laser photocoagulation. To the best of our knowledge, the present case is the first to report the combination of these findings. A 37-year-old, gravida 3 para 2, 31-week pregnant woman admitted to the emergency room with the complaint of headache, epigastric-right upper quadrant abdominal pain and vomiting. She had persistently high systolic and diastolic blood pressures. On physical examination, significant edema was detected in her legs over the tibia. She had no history of systemic or ocular disease, operation or trauma. She was hospitalized with the diagnosis of preeclampsia. Antihypertensive therapy with methyldopa 250 mg po bid was started. Maintenance of strict fluid balance, selective haemodynamic monitoring, and selective plasma volume expansion with close maternal and fetal monitoring were provided. In the second week, she complained of acute visual disturbances such as blurred vision and a visual acuity loss in her left eye. Her ophthalmological consultation revealed that she had a best-corrected visual acuity of 20/200 and 20/20 with normal color vision tests, in the left and right eyes, respectively. Both eyes revealed normal anterior segment findings with no rubeosis iridis. Fundus examination revealed segmental intraretinal hemorrhage, dilated and the tortous retinal veins in both eyes. Moreover, the left eye had retinal neovascularisations (1/2 disc diameter) in the upper temporal sector with slight macular edema consistent with the diagnosis of the upper temporal retinal vein occlusion. Intraocular pressure readings were both found to be within normal limits. Ortoptic examination of the eyes revealed no deviation. Refractive values of the both eyes were “ – 0,25 D”. There were no anisocoria. Visual field tests performed with Humphrey Field Analyzer II using central 30-2, SITA Standard strategy showed a normal test in the right eye while absolute scotoma in the lower nasal quadrant in the left eye was noted. She refused fundus flourescein angiography and we informed her of the possible risks to the fetus. She consulted with an internist for a probable underlying coagulopathy and vasculopathy, namely lupus erythematosus. Overall, she was diagnosed as preeclampsic. After obtaining written informed consent, scatter retinal photocoagulation was applied in the upper temporal region of the left fundus using 250 argon green laser bursts with a spot diameter of 500 micron, and with a duration of 0.1 seconds. We analysed her visual field testings three days and one week after the laser therapy. There was an apparent partial improvement in the scotoma region with an increase in the mean sensitivity and a decrease in the mean deviation of the visual field by the end of the first week. All of the visual field tests, before and after the laser treatment, were reliable Visual acuity of the left eye improved to 40/200 at the first week examination, with no further improvement at the first month examination. A variety of occlusive vascular disorders may occur during pregnancy. These disorders include a Purtscher-like retinopathy, or ocular changes associated with disseminated intravascular coagulation, thrombotic thrombocytopenic purpura, and amniotic fluid embolism.2 The most common retinal abnormality seen in preeclampsia is focal arteriolar spasm and narrowing.3 In the second week of admission, she devoloped acute branch retinal vein occlusion. Following retinal laser photocoagulation treatment, which was performed on the same day of the diagnoses, she was found to partially recover the absolute scotoma seen in computerised visual field analysis. Apaydin et al showed that mean sensitivity of the central visual field has improved significantly 3 months after panretinal laser photocoagulation treatment.4 Akar et al found that significant changes seen in optic rim parameters has lasted more than 4 months after laser therapy.5 Palacz and Sylwestrzak showed that early laser photocoagulation treatment is beneficial in the treatment of the retinal vein thrombosis and besides that, pharmacological treatment coupled with laser photocoagulation gives much better results than the pharmacotherapy alone.6 On the other hand, it is a well-known fact that there is a learning curve with automated perimetry.7 The improvement noted in our case could be due to the improvement in the performance of the test. Preeclampsia, as involving multiple organ systems, still remains an important cause of perinatal and maternal mortality and morbidity in all countries of the world.8 It should be screened through multidisciplinary approach. It seems crucial to have comprehensive baseline dilated eye examination before conception and regular follow up ophthalmologic examinations during pregnancy.