Background: Traumatic hyphema is the entry of blood into the anterior chamber (the space between the cornea and iris) subsequent to a blow or a projectile striking the eye. Hyphema uncommonly causes permanent loss of vision. Associated trauma (e.g. corneal staining, traumatic cataract, angle recession glaucoma, optic atrophy, etc.) may seriously affect vision. Such complications can lead to permanent impairment of vision. People with sickle cell trait/disease may be particularly susceptible to increases of elevated intraocular pressure. If rebleeding occurs, the rates and severity of complications increase.
Objectives: To assess the effectiveness of various medical interventions in the management of traumatic hyphema.
Search methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2018, Issue 6); MEDLINE Ovid; Embase.com; PubMed (1948 to June 2018); the ISRCTN registry; ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). The date of the search was 28 June 2018.
Selection criteria: Two review authors independently assessed the titles and abstracts of all reports identified by the electronic and manual searches. In this review, we included randomized and quasi-randomized trials that compared various medical (non-surgical) interventions versus other medical intervention or control groups for the treatment of traumatic hyphema following closed-globe trauma. We applied no restrictions regarding age, gender, severity of the closed-globe trauma, or level of visual acuity at the time of enrollment.
Data collection and analysis: Two review authors independently extracted the data for the primary outcomes, visual acuity and time to resolution of primary hemorrhage, and secondary outcomes including: secondary hemorrhage and time to rebleed; risk of corneal blood staining, glaucoma or elevated intraocular pressure, optic atrophy, or peripheral anterior synechiae; adverse events; and duration of hospitalization. We entered and analyzed data using Review Manager 5. We performed meta-analyses using a fixed-effect model and reported dichotomous outcomes as risk ratios (RR) and continuous outcomes as mean differences (MD).
Main results: We included 20 randomized and seven quasi-randomized studies with a total of 2643 participants. Interventions included antifibrinolytic agents (systemic and topical aminocaproic acid, tranexamic acid, and aminomethylbenzoic acid), corticosteroids (systemic and topical), cycloplegics, miotics, aspirin, conjugated estrogens, traditional Chinese medicine, monocular versus bilateral patching, elevation of the head, and bed rest.We found no evidence of an effect on visual acuity for any intervention, whether measured within two weeks (short term) or for longer periods. In a meta-analysis of two trials, we found no evidence of an effect of aminocaproic acid on long-term visual acuity (RR 1.03, 95% confidence interval (CI) 0.82 to 1.29) or final visual acuity measured up to three years after the hyphema (RR 1.05, 95% CI 0.93 to 1.18). Eight trials evaluated the effects of various interventions on short-term visual acuity; none of these interventions was measured in more than one trial. No intervention showed a statistically significant effect (RRs ranged from 0.75 to 1.10). Similarly, visual acuity measured for longer periods in four trials evaluating different interventions was also not statistically significant (RRs ranged from 0.82 to 1.02). The evidence supporting these findings was of low or very low certainty.Systemic aminocaproic acid reduced the rate of recurrent hemorrhage (RR 0.28, 95% CI 0.13 to 0.60) as assessed in six trials with 330 participants. A sensitivity analysis omitting two studies not using an intention-to-treat analysis reduced the strength of the evidence (RR 0.43, 95% CI 0.17 to 1.08). We obtained similar results for topical aminocaproic acid (RR 0.48, 95% CI 0.20 to 1.10) in two studies with 121 participants. We assessed the certainty of these findings as low and very low, respectively. Systemic tranexamic acid had a significant effect in reducing the rate of secondary hemorrhage (RR 0.31, 95% CI 0.17 to 0.55) in five trials with 578 participants, as did aminomethylbenzoic acid as reported in one study (RR 0.10, 95% CI 0.02 to 0.41). The evidence to support an associated reduction in the risk of complications from secondary hemorrhage (i.e. corneal blood staining, peripheral anterior synechiae, elevated intraocular pressure, and development of optic atrophy) by antifibrinolytics was limited by the small number of these events. Use of aminocaproic acid was associated with increased nausea, vomiting, and other adverse events compared with placebo. We found no evidence of an effect in the number of adverse events with the use of systemic versus topical aminocaproic acid or with standard versus lower drug dose. The number of days for the primary hyphema to resolve appeared to be longer with the use of systemic aminocaproic acid compared with no use, but this outcome was not altered by any other intervention.The available evidence on usage of systemic or topical corticosteroids, cycloplegics, or aspirin in traumatic hyphema was limited due to the small numbers of participants and events in the trials.We found no evidence of an effect between a single versus binocular patch or ambulation versus complete bed rest on the risk of secondary hemorrhage or time to rebleed.
Authors' conclusions: We found no evidence of an effect on visual acuity by any of the interventions evaluated in this review. Although evidence was limited, it appears that people with traumatic hyphema who receive aminocaproic acid or tranexamic acid are less likely to experience secondary hemorrhaging. However, hyphema took longer clear in people treated with systemic aminocaproic acid.There is no good evidence to support the use of antifibrinolytic agents in the management of traumatic hyphema other than possibly to reduce the rate of secondary hemorrhage. Similarly, there is no evidence to support the use of corticosteroids, cycloplegics, or non-drug interventions (such as binocular patching, bed rest, or head elevation) in the management of traumatic hyphema. As these multiple interventions are rarely used in isolation, further research to assess the additive effect of these interventions might be of value.