Abstract
Purpose :
Observational studies have suggested that intravenous tissue plasminogen activator (IV-tPA) may improve vision after acute central retinal artery occlusion (CRAO) when given within 4.5 hours of symptom onset. We performed a retrospective study to determine visual improvement and adverse events when using IV-tPA in conjunction with hyperbaric oxygen (HBO).
Methods :
This retrospective study compared 8 patients who received 0.9 mg/kg IV-tPA within 4.5 hours of symptom onset and HBO within 6 hours (IV-tPA+HBO) with 9 patients who received HBO only within 6 hours. HBO treatment was 2.8 atmospheres for 90 minutes twice a day for five days. Visual acuity, inner retinal edema (measured on Heidelberg Spectralis optical coherence tomography (OCT) as inner nuclear layer to inner limiting membrane compared to unaffected side), and neuroimaging were reviewed. Visual acuity better than 20/100 was considered as clinical improvement.
Results :
All patients had 20/400 vision or worse at presentation. At discharge, visual acuity in the HBO group was worse for 1, the same for 4, and better for 4. In the IV-tPA+HBO group, 1 was worse, 2 were the same, and 5 were better. Three (38%) IV-tPA+HBO patients had clinical improvement at discharge, compared to one (11%) HBO patient. Combining both groups, patients who had clinical improvement had less inner retinal edema (37.75±70.7 µm) compared with those who did not recover (133.3±45.4 µm, P<0.05). There was no difference in the amount of inner retinal edema between those who received HBO compared to IV-tPA+HBO (110.0±38.5 µm vs. 108.6±94.1 µm, P=0.96). Of the IV-tPA+HBO patients who improved, one had an iatrogenic CRAO caused by diagnostic angiography, one had cilioretinal artery sparing, and one had no OCT findings of inner retina edema. No patients in the HBO group had ischemia on neuroimaging, while in the IV-tPA+HBO group, four had ischemia and one had symptomatic intracranial hemorrhage resulting in long-term arm weakness and limitations in ambulation.
Conclusions :
Clinical improvement in vision was associated with less post-treatment inner retinal edema. However, inner retinal edema was not significantly differently between patients who received IV-tPA+HBO compared to HBO only. The risk of symptomatic intracranial hemorrhage and increased silent ischemic stroke limits the clinical utility of IV-tPA in CRAO.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.