Computed Tomography Angiography Spot Sign Research Articles

Postcontrast CT Extravasation Is Associated With Hematoma Expansion in CTA Spot Negative Patients

The purpose of this study was to assess the effect of postcontrast CT (PCCT) leakage (PCL) on hematoma growth in CTA spot negative patients. A retrospective study of 61 patients presenting within 6 hours of primary ICH onset imaged with CT angiography (CTA) and PCCT. Presence of CTA spot sign and PCL were documented. PCL was defined as the presence of contrast extravasation on the PCCT study at a location remote from the CTA spot sign if present. Hematoma expansion was defined as >6 mL or 30% hematoma enlargement. Patients were dichotomized by CTA spot sign presence and PCL and compared for baseline demographic data, hematoma size, and growth using the unpaired t test and Mann-Whitney test for continuous and categorical data, respectively. A probability value <0.05 was considered significant. PCL was present in 11/61 patients (18%), occurring in 5 without a spot sign (45%). Spot negative PCL patients demonstrated larger absolute (P=0.02) and percentage hematoma growth (P=0.02) compared to those without PCL. The mean volume and percent increase was 6.7 mL and 26%, respectively. Inclusion of PCL together with CTA spot sign as risk factor for hematoma expansion increased sensitivity from 0.78 (95% CI; 0.52 to 0.94) to 0.94 (95% CI; 0.72 to 1.00) and NPV from 0.90 (95% CI; 0.76 to 0.97) to 0.97 (95% CI; 0.85 to 1.00). Inclusion of PCCT in the investigation of ICH patients allows detection of PCL which, together with the CTA spot sign, increases sensitivity and negative predictive value for predicting hematoma expansion. This finding should be validated in larger studies.

Vascular and Nonvascular Mimics of the CT Angiography “Spot Sign” in Patients With Secondary Intracerebral Hemorrhage

The newly-described computed tomography angiography (CTA) Spot Sign is present in about one third of patients with acute primary intracerebral hemorrhage (PICH) and predicts hematoma expansion. This sign has not been systematically evaluated in patients with secondary causes of ICH, and mimics have not been characterized. The purpose of this study was to assess for the presence of the Spot Sign in secondary ICH and to document potential mimics of the Spot Sign and their distinguishing features. We performed a retrospective chart review of consecutive patients presenting with ICH to our regional stroke center between January 2002 and May 2007. Ninety-six ICH patients underwent a CT stroke protocol including CTA. CTA documented a secondary cause for hemorrhage in 30 patients (31%). Each patient was assessed for the presence or absence of the CTA Spot Sign or a mimic by 2 blinded neuroradiologists. Clinical and radiological features of PICH and secondary ICH were compared. No patients with secondary ICH had a true CTA Spot Sign, but several Spot Sign mimics were identified including: micro AVM, posterior communicating artery aneurysm, Moya Moya, and neoplasm-associated calcification. The secondary ICH group was younger (P=0.0001) and less likely to be hypertensive at presentation (P=0.0114). Significant hematoma expansion (>33% increase from baseline volume) occurred in 20% of secondary ICH patients and 28% of PICH patients (P=0.2463). This study describes mimics of the CTA Spot Sign and classifies them as vascular (microAVM, aneurysm, Moya Moya) or nonvascular (tumor and choroid plexus calcification). Evaluation of the noncontrast CT together with the CTA source images is an essential part of the evaluation for the Spot Sign. Vessels entering the hematoma from the periphery are indicative of an underlying vascular lesion. Our findings suggest that the Spot Sign may be rare in secondary ICH and most specific for PICH.

CT Angiography “Spot Sign” Predicts Hematoma Expansion in Acute Intracerebral Hemorrhage

Morbidity and mortality in spontaneous intracerebral hemorrhage (ICH) are correlated with hematoma progression. We hypothesized that the presence of tiny, enhancing foci ("spot sign") within acute hematomas is associated with hematoma expansion. We prospectively studied 39 consecutive patients with spontaneous ICH by computed tomography angiography within 3 hours of symptom onset. Scans were reviewed by 3 readers. Patients were dichotomized according to the presence or absence of the spot sign. Clinical and radiological outcomes were compared between groups. The predictive value of this sign was assessed in a multivariate analysis. Thirteen patients (33%) demonstrated 31 enhancing foci. Baseline clinical variables were similar in both groups. Hematoma expansion occurred in 11 patients (28%) on follow-up. Seventy-seven percent of patients with and 4% without hematoma expansion demonstrated the spot sign (P<0.0001). Sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio for expansion were 91%, 89%, 77%, 96%, and 8.5, respectively. Interobserver agreement was high (kappa=0.92 to 0.94). In patients with the spot sign, mean volume change was greater (P=0.008), extravasation more common (P=0.0005), and median hospital stay longer (P=0.04), and fewer patients achieved a good outcome (modified Rankin Scale score <2), although the latter was not significant (P=0.16). No differences in hydrocephalus (P=1.00), surgical intervention (P=1.00), or death (P=0.60) were noted between groups. In multiple regression, the spot sign independently predicted hematoma expansion (P=0.0003). The computed tomography angiography spot sign is associated with the presence and extent of hematoma progression. Fewer patients achieve a good clinical outcome and hospital stay was longer. Further studies are warranted to validate the ability of this sign to predict clinical outcomes.