Terson's syndrome - Pathophysiologic considerations of an underestimated concomitant disease in aneurysmal subarachnoid hemorrhage

Management of Terson Syndrome: Long-Term Experience in a Single Center

BACKGROUND/OBJECTIVES

Terson Syndrome (TS) is a rare entity consisting of an intraocular hemorrhage secondary to subarachnoid hemorrhage (SAH) or intracerebral hemorrhage (IH). This study aimed to retrospectively describe the experience of the Ophthalmology Unit of Policlinico Gemelli, Rome, in the management of TS.

METHODS

Twenty-four eyes of 19 patients (10 males-53%; 9 females-47%; mean age of 44.73 ± 12.49 years) with TS who had pars plana vitrectomy between 2011 and 2024 were included. The primary outcome was the mean change in best-corrected visual acuity (BCVA) 1-3 months after surgery. The secondary outcome was the correlation of post-operative BCVA with the timing of vitrectomy (early vs. late, ≤100 or >100 days).

RESULTS

The time between diagnosis and surgery ranged from 33 to 284 days (median = 102 days, interquartile range IQR = 74-161). Baseline BCVA ranged from 6 to 50 ETDRS letters with a median of 17 letters (IQR = 15-25) and significantly increased after surgery, with a median value of 80 (IQR = 70-85). The BCVA percentage improvement had a median of 325% (IQR = 300-431%). No differences in post-operative BCVA were found between patients who underwent early or late vitrectomy. One vitrectomy was complicated by an endophthalmitis.

CONCLUSIONS

Although no clear guidelines exist on managing TS, vitrectomy significantly improves BCVA, and a delay in surgical intervention does not necessarily worsen the functional outcome. However, an early vitrectomy could improve the stimuli perception, facilitating the rehabilitation process.

Terson Syndrome Diagnosed by Ocular Point of Care Ultrasound on the Medical Floor

In acute care environments, accurately assessing complications of intracranial pathology can be challenging. Ocular complications in acute intracranial disease are not consistently evaluated despite their high morbidity. We report on a case of monocular diplopia in a 63-year-old man with subacute traumatic brain injury with localized subarachnoid hemorrhage. Ocular point of care ultrasound (POCUS) identified features of vitreous hemorrhage in one globe, leading to a diagnosis of Terson syndrome and a timely referral to ophthalmology. This finding was made on the medical floor days after the initial presentation during rehabilitation when ophthalmoscopy was not possible, and vitreous hemorrhage had not been identified on presentation. Terson syndrome is a seldom discussed but important complication of intracranial hemorrhage generally associated with poor patient outcomes. Ocular POCUS can provide a useful alternative in assessing ocular complications of acute intracranial disease on the medical floor, particularly when the practicalities of performing ophthalmoscopy are challenged.

Terson Syndrome in Patients with Aneurysmal Subarachnoid Hemorrhage: A 10-Year Single-Center Experience

BACKGROUND

Terson syndrome (TS), an intraocular hemorrhage associated with aneurysmal subarachnoid hemorrhage (aSAH), occurs in up to 46% of all patients with subarachnoid hemorrhage. Despite its high incidence, TS is underrepresented in the literature, and patients with aSAH are sometimes not systematically evaluated for the presence of TS in clinical practice. This work aims to raise awareness of TS, reevaluate previous scientific findings, describe risk factors associated with the occurrence of TS, and present our local diagnostic and treatment concept.

METHODS

All patients with aSAH treated at our institution between October 2010 and May 2020 were included in this retrospective study. The frequency of ophthalmological screening by indirect funduscopy, as well as the results, was investigated. In addition, the collection and statistical analysis of epidemiological and clinical data was performed using χ2, Kruskal-Wallis, and analysis of variance testing; multivariate regression; and receiver operating characteristic analysis. The significance level was set at p < 0.05.

RESULTS

A total of 617 patients were treated for aSAH in our institution. Of these, 367 patients (59.5%) were ophthalmologically examined for the presence of TS. The rate of TS in the examined patients was 21.3% (n = 78). Patients with TS had significantly higher Fisher and World Federation of Neurosurgical Societies (WFNS) scores (p < 0.0001). Regression analyses showed WFNS grade (p = 0.003) and the occurrence of seizures (p = 0.002) as independent predictors of TS, as did receiver operating characteristic analyses, which had a significant area under the curve of 0.66 for the combination of WFNS grade and seizures. For 12 (15.4%) patients, the TS had to be surgically treated by pars plana vitrectomy in a total of 14 eyes, which resulted in significant improvement of visual function in all patients: mean preoperative best-corrected visual acuity was 0.03 (± 0.08) versus 0.76 (± 0.21) postoperatively (p < 0.001).

CONCLUSIONS

TS is a common complication in patients with aSAH, affecting approximately one in five patients. A higher WFNS grade and the occurrence of seizures are associated with TS; therefore, screening for TS should be performed in these patients.

Terson Syndrome - Clinical Presentation, Management, and Visual Outcomes in a Tertiary Centre

Purpose

The purpose of this study 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.

Patients and Methods

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.

Results

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 875% (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).

Conclusion

Terson syndrome is a potential cause of irreversible visual loss. Diagnosis delay may affect visual prognosis. 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.

Pathogenesis of Terson syndrome

Purpose

The aim of this experimental study was to investigate the pathogenesis of Terson syndrome (TS), which currently is controversial.

Methods

The central retinal artery (in 39 orbits), posterior ciliary arteries (in 8 orbits), and central retinal vein (CRV in 21 orbits) were occluded in rhesus monkeys by exposing them to lateral orbitotomy. Fundus examination and fluorescein fundus angiography were performed before and immediately after cutting the vessels and serially thereafter during the follow-up period. The rationale of the experimental study design is discussed.

Results

In eyes with central retinal artery occlusion, retinal hemorrhages were seen soon after the procedure in 7 eyes, and on follow-up in a total of 15 eyes. In posterior ciliary artery occlusion, retinal hemorrhages were seen soon after the procedure in one eye, and on follow-up in a total of three eyes. In eyes with CRV, all eyes had extensive scattered retinal hemorrhages.

Conclusion

The findings of this experimental study, and my basic, experimental, and comprehensive clinical studies on CRVO, suggest the following concept of the pathogenesis of TS: Compression of the CRV plays a crucial role in the development of TS. The CRV is compressed, as it lies in the subarachnoid space of the optic nerve sheath, by raised cerebrospinal fluid pressure and/or accumulated blood.

. This results in retinal

venous stasis and raised venous pressure in the retinal veins, leading to venous engorgement, rupture of the retinal capillaries.

and

retinal hemorrhages. The clinical importance of compression of the CRV and not occlusion of CRV in TS is that optic nerve sheath decompression by opening it and releasing the blood and raised cerebrospinal fluid (CSF) pressure, would result in immediate decompressing of the CRV in the subarachnoid space and restoration of normal circulation and prevent visual loss.

Ultrasound diagnosis of Terson syndrome as an indicator of extreme severity in neurocritical care patients

INTRODUCTION

Terson syndrome (TS) is defined as any intraocular haemorrhage identified in patients with acute intracranial pathology. TS appears to be associated with clinical severity in patients with subarachnoid haemorrhage (SAH), but the association is yet to be defined in patients with traumatic brain injury (TBI) and intracerebral haemorrhage (ICH). This study aimed to evaluate the diagnostic performance of ocular ultrasound (OU) and its usefulness in clinical practice.

MATERIAL AND METHODS

We performed an observational, prospective, single-centre study of neurocritical care patients. We analysed cases and controls, defined according to indirect ophthalmoscopy (IO) and OU findings. We determined the diagnostic characteristics of OU. A multivariate analysis was performed to identify clinically relevant associations.

RESULTS

The sample included 91 patients diagnosed with ICH (41.76%), SAH (29.67%), and TBI (28.57%). TS was identified by OU in 8 patients (8.79%) and by IO in 24 (24.37%). The adjusted mortality rate in patients with TS showed an odds ratio (OR) of 4.15 (95% confidence interval [CI], 1.52-11.33). All patients with TS detected by OU presented Glasgow Coma Scale scores < 9, with an elevated risk of needing decompressive craniectomy (OR: 9.84; 95% CI, 1.64-59). OU presented an overall sensitivity of 30.43%, specificity of 98.53%, and diagnostic accuracy of 81.32%. For the detection of vitreous haemorrhage, sensitivity and specificity were 87.5% and 98.5%, respectively.

CONCLUSIONS

OU diagnosis of TS identifies extremely critical patients, who may require the highest level of care; TS is an independent risk factor for in-hospital mortality.

Vascular Reactivity to Hypercapnia Is Impaired in the Cerebral and Retinal Vasculature in the Acute Phase After Experimental Subarachnoid Hemorrhage

Objective: Impaired cerebral blood flow (CBF) regulation, such as reduced reactivity to hypercapnia, contributes to the pathophysiology after aneurysmal subarachnoid hemorrhage (SAH), but temporal dynamics in the acute phase are unknown. Featuring comparable molecular regulation mechanisms, the retinal vessels participate in chronic and subacute stroke- and SAH-associated vessel alterations in patients and can be studied non-invasively. This study is aimed to characterize the temporal course of the cerebral and retinal vascular reactivity to hypercapnia in the acute phase after experimental SAH and compare the potential degree of impairment.

Methods: Subarachnoid hemorrhage was induced by injecting 0.5 ml of heparinized autologous blood into the cisterna magna of male Wistar rats using two anesthesia protocols [isoflurane/fentanyl n = 25 (Sham + SAH): Iso—Group, ketamine/xylazine n = 32 (Sham + SAH): K/X—Group]. CBF (laser speckle contrast analysis) and physiological parameters were measured continuously for 6 h. At six predefined time points, hypercapnia was induced by hypoventilation controlled via blood gas analysis, and retinal vessel diameter (RVD) was determined non-invasively.

Results: Cerebral reactivity and retinal reactivity in Sham groups were stable with only a slight attenuation after 2 h in RVD of the K/X—Group. In the SAH Iso—Group, cerebral and retinal CO2 reactivity compared to baseline was immediately impaired starting at 30 min after SAH (CBF p = 0.0090, RVD p = 0.0135) and lasting up to 4 h (p = 0.0136, resp. p = 0.0263). Similarly, in the K/X—Group, cerebral CO2 reactivity was disturbed early after SAH (30 min, p = 0.003) albeit showing a recovery to baseline after 2 h while retinal CO2 reactivity was impaired over the whole observation period (360 min, p = 0.0001) in the K/X—Group. After normalization to baseline, both vascular beds showed a parallel behavior regarding the temporal course and extent of impairment.

Conclusion: This study provides a detailed temporal analysis of impaired cerebral vascular CO2 reactivity starting immediately after SAH and lasting up to 6 h. Importantly, the retinal vessels participate in these acute changes underscoring the promising role of the retina as a potential non-invasive screening tool after SAH. Further studies will be required to determine the correlation with functional outcomes.

Terson's syndrome, the current concepts and management strategies: A review of literature

Terson's Syndrome describes intraocular hemorrhage secondary to an acutely raised intracranial pressure (ICP). Although Terson's Syndrome is common amongst patients with subarachnoid hemorrhage (SAH), it is underdiagnosed and often overlooked. This review discusses the current understanding of the etiopathogenesis, clinical features, and management of Terson's Syndrome and highlights the visual and prognostic implications to stress the importance of timely diagnosis and management. The origin of intraocular hemorrhage in Terson's Syndrome has been debated. A recognized theory suggests that an acutely raised ICP induces effusion of cerebrospinal fluid into the optic nerve sheath which dilates the retrobulbar aspect of the sheath in the orbit. Dilatation mechanically compresses the central retinal vein and retinochoroidal veins resulting in venous hypertension and rupture of thin retinal vessels. A commonly reported clinical feature is decreased visual acuity and blurred vision. These may be accompanied by symptoms of increased ICP including loss of consciousness and headache. Diagnosis is established using evidence from the clinical presentation, ophthalmoscopy, and, when required, imaging including B-mode ultrasound, CT, MRI, and fluorescein angiography. Terson's Syndrome is managed conservatively by observation for mild cases and with vitrectomy for bilateral cases and for patients whose hemorrhage has not spontaneously resolved after an observational period. Terson's Syndrome can be used as a prognostic indicator of morbidity and mortality in underlying pathology like SAH. Fundoscopy of patients with SAH, acutely raised ICP or visual disturbance with unknown etiology can help establish a timely Terson's Syndrome diagnosis. This may avoid the risk of permanent visual impairment.

An explanation for Terson syndrome at last: the glymphatic reflux theory

Terson Syndrome (TS) describes the presence of intraocular hemorrhage in patients with intracranial hemorrhage, typically subarachnoid hemorrhage. Despite TS being a well-defined and frequently occurring phenomenon, its pathophysiology remains controversial. This review will present the current understanding of TS, with view to describing a contemporary and more plausible pathomechanism of TS, given recent advances in ophthalmic science and neurobiology. Previously proposed theories include a sudden rise in intracranial pressure (ICP) transmitted to the optic nerve sheath leading to rupture of retinal vessels; or intracranial blood extending to the orbit via the optic nerve sheath. The origin of blood in TS is uncertain, but retinal vessels appear to be an unlikely source. In addition, an anatomical pathway for blood to enter the eye from the intracranial space remains poorly defined. An ocular glymphatic system has recently been described, drainage of which from the globe into intracranial glymphatics is reliant on the pressure gradient between intraocular pressure and intracranial pressure. The glymphatic pathway is the only extravascular anatomical conduit between the subarachnoid space and the retina. We propose that subarachnoid blood in skull base cisterns near the optic nerve is the substrate of blood in TS. Raised ICP causes it to be refluxed through glymphatic channels into the globe, resulting in intraocular hemorrhage. We herewith present glymphatic reflux as an alternative theory to explain the phenomenon of Terson Syndrome.

Ultrasound diagnosis of Terson syndrome as an indicator of extreme severity in neurocritical care patients

INTRODUCTION

Terson syndrome (TS) is defined as any intraocular haemorrhage identified in patients with acute intracranial pathology. TS appears to be associated with clinical severity in patients with subarachnoid haemorrhage (SAH), but the association is yet to be defined in patients with traumatic brain injury (TBI) and intracerebral haemorrhage (ICH). This study aimed to evaluate the diagnostic performance of ocular ultrasound (OU) and its usefulness in clinical practice.

MATERIAL AND METHODS

We performed an observational, prospective, single-centre study of neurocritical care patients. We analysed cases and controls, defined according to indirect ophthalmoscopy (IO) and OU findings. We determined the diagnostic characteristics of OU. A multivariate analysis was performed to identify clinically relevant associations.

RESULTS

The sample included 91 patients diagnosed with ICH (41.76%), SAH (29.67%), and TBI (28.57%). TS was identified by OU in 8 patients (8.79%) and by IO in 24 (24.37%). The adjusted mortality rate in patients with TS showed an odds ratio (OR) of 4.15 (95% confidence interval [CI], 1.52-11.33). All patients with TS detected by OU presented Glasgow Coma Scale scores < 9, with an elevated risk of needing decompressive craniectomy (OR: 9.84; 95% CI, 1.64-59). OU presented an overall sensitivity of 30.43%, specificity of 98.53%, and diagnostic accuracy of 81.32%. For the detection of vitreous haemorrhage, sensitivity and specificity were 87.5% and 98.5%, respectively.

CONCLUSIONS

OU diagnosis of TS identifies extremely critical patients, who may require the highest level of care; TS is an independent risk factor for in-hospital mortality.

Clinical characteristics of asymptomatic Terson syndrome in the patients with aneurysmal subarachnoid hemorrhage

AIM

To investigate clinical characteristics of asymptomatic Terson syndrome and its clinical impact in patients with aneurysmal subarachnoid hemorrhage (SAH).

METHODS

This retrospective, interventional study included 31 patients with aneurysmal SAH, and the medical records were reviewed. In addition to baseline characteristics of the study population such as age, sex, and underlying medical history, multi-modal imaging analysis, including fluorescein angiography (FA), spectral domain optical coherence tomography (SD-OCT), were also reviewed. Glasgow Coma Scale (GCS), Hunt-Hess (HH) grade, and Fisher scale at the time of admission, and functional outcome by using modified Rankin Scale (mRS) at 6mo were compared.

RESULTS

Of the 31 patients, 10 patients (32.3%) were diagnosed with Terson syndrome. All the patients with Terson syndrome did not report visual symptoms at the time of ophthalmologic screening. FA showed microvascular changes of retinal capillaries and varying degrees of disc leakage. SD-OCT allowed intuitive anatomical localization of multi-layered retinal hemorrhages and assessment of ellipsoid zone integrity. The patients with Terson syndrome showed significantly worse GCS (P=0.047) and HH grade (P=0.025) than those without, except Ficher scale (P=0.385). There was no significant difference in the mRS (P=0.250) at 6mo. Among baseline factors, the HH grade was the only significant factor associated with Terson syndrome (B=1.079, P=0.016).

CONCLUSION

In our study, 32.3% of the patients have Terson syndrome without visual symptoms. The baseline HH grade is significantly correlated with Terson syndrome, and there is no significant difference in the functional outcome between the patients with and without Terson syndrome. Terson syndrome may develop without any visual symptoms as shown in our study, and ophthalmologic screening may be recommended to prevent further visual deterioration especially in the patients with poor HH grade at the time of aneurysmal SAH.

OUTCOMES OF VITRECTOMY IN TERSON SYNDROME: A Multicenter Canadian Perspective

PURPOSE

To characterize the presentation of Terson syndrome, the occurrence of a vitreous hemorrhage in association with intracranial hemorrhage, and report on the outcomes of vitrectomy at two major centers in Canada.

METHODS

Retrospective chart review of consecutive patients with Terson syndrome undergoing vitrectomy by retina specialists over the last 10 years. Primary outcome was the change in best-corrected visual acuity (BCVA) at 3 months from baseline. Secondary outcomes included the association between baseline BCVA and final BCVA, and the association between final BCVA and timing of surgery (early vs. later than 90 days).

RESULTS

A total of 14 eyes of 11 patients were included. The mean time between observation of intraocular hemorrhage and vitrectomy was 160 days. Baseline preoperative BCVA was logarithm of the minimum angle of resolution 1.57 ± 1.03 (Snellen 20/740), which improved to logarithm of the minimum angle of resolution 0.53 ± 0.82 (Snellen 20/70) at the final postoperative follow-up, P = 0.01. Baseline BCVA was not significantly correlated with final BCVA, Spearman's rho = 0.016, P = 0.957. Final BCVA did not significantly differ between those who had surgery before 90 days compared with after 90 days, P = 0.087.

CONCLUSION

Vitrectomy is safe and effective and should be considered for nonclearing vitreal bleeding due to Terson syndrome. Ocular hemorrhaging in Terson syndrome can be observed conservatively for spontaneous improvement without the risk of reduced visual potential. Ophthalmic evaluation should be considered promptly after intracranial hemorrhage.

Terson syndrome secondary to subarachnoid hemorrhage: a case report and literature review

BACKGROUND

Terson syndrome is a serious complication of subarachnoid hemorrhage includes any intraocular hemorrhage and may result in blurred vision or even blindness. However, it is often overlooked clinically.

CASE DESCRIPTION

A 42-year-old man presented with coma due to rupture of a left posterior communicating artery aneurysm. A preoperative CT scan demonstrated subarachnoid hemorrhage (SAH) and bilateral fundus hemorrhage. Visual evoked potential (VEP) and B-scan ocular ultrasound revealed vitreous hemorrhages, features consistent with Terson syndrome. Pars plana vitrectomy was performed 2 weeks after SAH with a subsequent improvement of visual acuity.

CONCLUSIONS

Early identification is important for the recovery of the patient's nervous system and ophthalmology. Neurosurgeons should be aware of the pathology and pay attention to it to maximize patient's benefit.

Intracranial Aneurysms of Neuro-Ophthalmologic Relevance

BACKGROUND

Intracranial saccular aneurysms are acquired lesions that often present with neuro-ophthalmologic symptoms and signs. Recent advances in neurosurgical techniques, endovascular treatments, and neurocritical care have improved the optimal management of symptomatic unruptured aneurysms, but whether the chosen treatment has an impact on neuro-ophthalmologic outcomes remains debated.

EVIDENCE ACQUISITION

A review of the literature focused on neuro-ophthalmic manifestations and treatment of intracranial aneurysms with specific relevance to neuro-ophthalmologic outcomes was conducted using Ovid MEDLINE and EMBASE databases. Cavernous sinus aneurysms were not included in this review.

RESULTS

Surgical clipping vs endovascular coiling for aneurysms causing third nerve palsies was compared in 13 retrospective studies representing 447 patients. Complete recovery was achieved in 78% of surgical patients compared with 44% of patients treated with endovascular coiling. However, the complication rate, hospital costs, and days spent in intensive care were reported as higher in surgically treated patients. Retrospective reviews of surgical clipping and endovascular coiling for all ocular motor nerve palsies (third, fourth, or sixth cranial nerves) revealed similar results of complete resolution in 76% and 49%, respectively. Improvement in visual deficits related to aneurysmal compression of the anterior visual pathways was also better among patients treated with clipping than with coiling. The time to treatment from onset of visual symptoms was a predictive factor of visual recovery in several studies. Few reports have specifically assessed the improvement of visual deficits after treatment with flow diverters.

CONCLUSIONS

Decisions regarding the choice of therapy for intracranial aneurysms causing neuro-ophthalmologic signs ideally should be made at high-volume centers with access to both surgical and endovascular treatments. The status of the patient, location of the aneurysm, and experience of the treating physicians are important factors to consider. Although a higher rate of visual recovery was reported with neurosurgical clipping, this must be weighed against the potentially longer intensive care stays and increased early morbidity.