Can Baseline Computed Tomography Scans Be Used to Identify Patients at High Risk of Vision Loss due to Terson Syndrome?

Abstract

To determine if routinely performed computed tomographic (CT) scanning in patients with aneurysmal subarachnoid hemorrhages (aSAHs) is sufficient to identify patients at high risk of vision loss due to Terson syndrome (TS). METHODS: Consecutive patients with a diagnosis of aSAH admitted to the neurologic intensive care unit of a regional referral hospital over a 3-year period were prospectively evaluated. Head CT scans performed in the emergency department were assessed for the presence of a ''crescent sign'' (evidence of significant subinternal limiting membrane hemorrhage). Dilated funduscopic examinations were performed by an ophthalmologist, masked to the results of the CT scan, to identify retinal and vitreous hemorrhages consistent with TS. Retinal hemorrhages were categorized according to size-those smaller than 2 mm in diameter were deemed low risk (lrTS) for vision loss and those larger than 2 mm in diameter were deemed high risk (hrTS) for vision loss. RESULTS: One hundred seventeen patients with aSAH were enrolled in the study. The overall incidence of TS was 24.9% (29 of 117 patients; 12 were bilateral). Compared to patients without TS, those with TS had a higher Fisher Hemorrhage Grade and a lower mean (±standard deviation) GCS score (8.66 ± 4.97 vs 12.09 ± 1.10; P < 0.001). The CT crescent sign was positive in 7 patients (6.0%), 6 (5.1%; 2 were bilateral) of whom were found to have hrTS. Of the 110 patients without a CT crescent sign, 88 (75.1%) patients did not have TS, 21 had lrTS, and 1 patient had hrTS in one eye. The CT crescent sign was highly sensitive (85.7%) and specific (99.1%) for diagnosing hrTS. CONCLUSION: The CT crescent sign is a highly sensitive and specific marker for hrTS. CT scanning may replace routine ophthalmologic examinations to identify patients at risk of vision loss due to aSAH. (Am J

Terson sign:

“…Stewart et al 13 Prospective study with 117 patients with aneurysmal SAH The patient presented visual acuity of 30 cm in the right eye and 0.6 in the left eye when counting the fingers. CT and MRI did not show changes in the visual pathways.…”

“…22 In contrast, Stewart et al, in their prospective study, found an increased signal sensitivity (presence of significant sub-internal limiting hemorrhage of the membrane) on CT for the diagnosis of TS in 85.7% high-risk patients and 99.1% specificity. 13 Kang et al, reports that other conditions, such as leukemia, can lead to retinal hemorrhage, suggesting a simultaneous pathogenesis with Terson's syndrome. 5…”

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

“…Head computerized tomography (CT) scans requested during the monitorization of the neurological condition were reviewed to determine if a crescent sign in the posterior pole of the eye was present, which would constitute evidence of sub-ILM haemorrhage. 8 …”

“…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, 8 or that subarachnoid blood in skull base cisterns near the optic nerve is refluxed into the globe through glymphatic channels, leading to intraocular hemorrhage. 3 …”

Akuter binokularer Visusverlust bei Basilarisaneurysma-bedingter Subarachnoidalblutung

“…In einer Studie der Mayo Clinic Florida, welche sich auf retinale Blutungen mit einem Durchmesser von 2 mm oder mehr fokussiert, wurden eine Sensitivität von 85,7 % und eine Spezifität von 99,1 % erreicht. Die Autoren sehen hierin eine effiziente Selektionsmöglichkeit und Alternative zur initialen ophthalmologischen Untersuchung am Patientenbett als klinische Routine [6].…”