Terson Syndrome-Clinical Presentation, Management, and Visual Outcomes

In almost 150 years since its description, the physiopathology of Terson syndrome is still controversial. The most accepted theory is that the sudden increase in intracranial pressure closes the central retinal vein and its choroidal anastomoses, halting venous blood flow from the retina and raising intraluminal pressure within all branches of the vein. When coupled with unimpeded arterial blood flow into the retina, the resultant high intraluminal pressure ruptures the veins and causes bleeding into the retina. Alternative theories suggest that subarachnoid blood may pass into the cerebrospinal fluid surrounding the optic nerve or cause veins within the optic nerve sheath to rupture and then progress through the retinal layers, internal limiting membrane (ILM), and posterior hyaloid membrane, or that subarachnoid blood in skull base cisterns near the optic nerve is refluxed into the globe through glymphatic channels, leading to intraocular hemorrhage.

The diagnosis of Terson syndrome is usually delayed, given the presence of concomitant neurological deficits and depressed conscious state, which limit formal assessment of visual acuity loss. In many patients, ocular haemorrhage resolves spontaneously after a period of observation. If after conservative management, vitreous and/or preretinal haemorrhage does not clear and visual deficits persist, surgical treatment with pars plana vitrectomy (PPV) is recommended. The purpose of this study by Lima-Fontes et al was to characterize the clinical presentation, management strategy and visual outcomes of patients diagnosed with Terson syndrome and followed in a tertiary centre in Portugal.

A single-centre retrospective study was performed, based on the survey review of the medical records of every consecutive patient diagnosed with Terson syndrome and followed from January 2018 to August 2021. The change in best corrected visual acuity (BCVA) from baseline to the final evaluation was the primary outcome.

• Fifteen eyes from 8 patients (50% female) were included. The mean age at diagnosis was 55±7 years. The neurological event was traumatic brain injury in 37.5% (n=3) and subarachnoid haemorrhage in 62.5% of the patients (n=5).

• Bilateral intraocular haemorrhage occurred in 87.5% (n=7) of the patients.

• Vitreous and preretinal haemorrhages occurred each in 66.7% (n=10), intraretinal in 30% (n=3) and subretinal in 13.3% (n=2) of the eyes.

• In 40% of the eyes (n=6), spontaneous resolution of intraocular haemorrhage occurred, while PPV was performed in the remaining 60% (n=9).

• Ocular haemorrhage detection occurred 58.47 ± 40.94 days after the neurological event (range 11 to 121 days).

• Baseline BCVA was 1.11 ± 1.01 logMAR and improved to 0.32 ± 0.69 logMAR in the follow-up period (p=0.004). A positive correlation was found between initial and final BCVA (Spearman’s rho = 0.643, p=0.01). Baseline BCVA of eyes undergoing PPV was lower than of those conservatively managed (1.84±0.72 vs 0.20±0.28 logMAR, p<0.001). However, there were no statistically significant differences in final BCVA after surgery or observation (0.56 ± 0.90 vs 0.04 ± 0.04 logMAR, p=0.149). Longer periods between the neurological and the ophthalmological diagnosis were correlated with worse final BCVA (Spearman’s rho = 0.688, p=0.005).><0.001). However, there were no statistically significant differences in final BCVA after surgery or observation (0.56 ± 0.90 vs 0.04 ± 0.04 logMAR, p=0.149).

Longer periods between the neurological and the ophthalmological diagnosis were correlated with worse final BCVA (Spearman’s rho = 0.688, p=0.005).

In conclusion, Terson syndrome is a potential cause of irreversible visual loss. Evaluation by an ophthalmologist is essential in the initial stages of traumatic brain injury or subarachnoid/intracerebral haemorrhage, particularly if presenting ophthalmologic complaints or depressed neurological status. Early diagnosis permits the adoption of conservative measures and the identification of patients who are more likely to require surgery. PPV is indicated when intraocular haemorrhage is dense and does not resolve spontaneously or when visual acuity at presentation is low, allowing for good visual outcomes with minimal complications. More awareness about Terson syndrome is essential to minimize the diagnosis delay and improve visual outcomes.

Source: Lima-Fontes et al; Clinical Ophthalmology 2023:17 https://doi.org/10.2147/OPTH.S396781