Effect of blunt ocular trauma on retinal microvasculature: An optical coherence tomography angiography study

Investigation of Retinal Vascular Parameters and Choroidal Vascular Index in Patients Developing Hyphema After Unilateral Blunt Trauma

BACKGROUND

To evaluate retinal and choroidal vascular changes in cases with hyphema after blunt ocular trauma that did not cause globe rupture or any retinal pathology.

METHODS

This cross-sectional study included 29 patients who developed hyphema after unilateral blunt ocular trauma (BOT). The other healthy eyes of the same patients were evaluated as the control group. Optical coherence tomography-angiography (OCT-A) was used for imaging. In addition, choroidal parameters were compared by calculating the choroidal vascular index (CVI) and using choroidal thickness measurements by two independent researchers.

RESULTS

Superior and deep flow values were significantly decreased in the traumatic hyphema group compared to the control group (p<0.05). Parafoveal deep vascular density (parafoveal dVD) values were decreased in traumatized eyes compared to control eyes (p=0.000). Vascular density values were similar other than that. In addition, there was a significant decrease in optic disc blood flow (ODF) and optic nerve head density (ONHD) values compared to the control group (p<0.05). In addition, no significant difference was observed between the groups in terms of mean CVI values (p>0.05).

CONCLUSION

Non-invasive diagnostic tools such as OCTA and EDI-OCT can be used to detect and monitor early changes in retinal and choroidal microvascular flow in cases of traumatic hyphema.

Analyses of Foveal Avascular Zone in Patients with General Blunt Ocular Trauma Using Optical Coherence Tomography Angiography

PURPOSE

To investigate the effect of blunt ocular trauma (BOT) on foveal circulation, and in particular the foveal avascular zone (FAZ), using optical coherence tomography angiography (OCTA).

METHODS

This retrospective study consisted of 96 eyes (48 traumatized eyes and 48 nontraumatized eyes) from 48 subjects with BOT. We analyzed the FAZ area of deep capillary plexus (DCP) and superficial capillary plexus (SCP) immediately after BOT and at 2 weeks after BOT. We also evaluated the FAZ area of DCP and SCP in patients with and without blowout fracture (BOF).

RESULTS

There were no significant differences in FAZ area between traumatized and nontraumatized eyes at DCP and SCP in the initial test. In traumatized eyes, the FAZ area at SCP was significantly reduced on follow-up when compared to initial test (p = 0.01). In case of eyes with BOF, there was no significant differences in FAZ area between traumatized and nontraumatized eyes at DCP and SCP on initial test. No significant difference of FAZ area was found on follow-up relative to the initial test, whether in the DCP or SCP. In case of eyes without BOF, there was no significant differences of FAZ area between traumatized and nontraumatized eyes at DCP and SCP in initial test. Also, no significant difference of FAZ area at DCP was found on follow-up test compared to initial test. However, the FAZ area at SCP was significantly reduced in follow-up test compared with that in the initial test (p = 0.04).

CONCLUSIONS

Temporary microvascular ischemia occurs in the SCP of patients after BOT. Patients should be warned of transient ischemic changes that may occur after trauma. OCTA can provide useful information regarding the subacute changes in the FAZ at SCP after BOT, even without evident findings of structural damage on fundus examination.