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

PURPOSE: 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.

Early Absent Pupillary Light Reflexes After Cardiac Arrest in Patients Treated with Therapeutic Hypothermia.

Loss of pupillary light reactivity is one recognized indicator of poor prognosis after cardiopulmonary resuscitation (CPR). However, drug overdose, low cardiac output, and/or resuscitation drugs can lead to impaired pupillary light reflex. To investigate pupillary light reflex status before therapeutic hypothermia (TH) in relation to neurological outcome, we retrospectively reviewed the data of a prospectively implemented TH protocol in patients with cardiac arrest (CA) at Mayo Clinic in Jacksonville, Florida (January 2006-January 2012), and Mayo Clinic in Scottsdale, Arizona (August 2010-March 2014). During this period, all CA patients who underwent hypothermia were included. These patients were selected from an institutional database and hypothermia data set. The Cerebral Performance Category (CPC) at time of discharge was our primary outcome measure. A CPC of 1 to 2 was defined as good outcome and a CPC from 3 to 5 was defined as poor outcome. We identified 99 patients who had CA treated with TH. Twenty-nine patients (29%) had pupils that were nonreactive to light on admission examination before TH, eight of whom later had return of pupil reactivity by day 3. Two of these 29 patients (6.9%) had good outcome, compared to 24 of 70 patients (34.3%) with pupils that were reactive to light (p = 0.005). Both of these patients had CA after illicit drug overdose. Early nonreactive pupils occurred in almost a third of patients after CPR and before TH in our patient population. Recovery of pupillary light reactivity is possible, and in a small minority of those cases (particularly when CA is preceded by the use of illicit drugs), a good outcome can be achieved.