Alexander E. Merkler, MD

Orito K, Hirohata M, Nakamura Y, Takeshige N, Aoki T, Hattori G, et al. Leakage Sign for Primary Intracerebral Hemorrhage: A Novel Predictor of Hematoma Growth. Stroke. 2016

Intracerebral hemorrhage (ICH) is a devastating disease with a one-month mortality of 40%. Although initial ICH volume is the strongest predictor of mortality, hematoma expansion is a potentially modifiable risk factor that correlates well with both functional outcome and death and occurs in up to 40% of patients with ICH. Research has therefore been focused on methods to 1) identify patients at risk of hematoma expansion and 2) reduce hematoma expansion.

The “spot sign” has been previously correlated with both hematoma expansion and poor functional outcome; however, the spot sign is not a perfect predictor of hematoma expansion. Although the specificity of the spot sign is high, the sensitivity is only around 50%. In this study, Drs. Orito and Morioka et al evaluate a new predictor for hematoma expansion in ICH: the “leakage sign.”

The authors evaluate 80 patients with a primary ICH who underwent a CTA and a second CT (delayed phase image) 5 minutes later. The leakage sign was determined by comparing the arterial and delayed phase CT images. Each neuroradiologist measured a region of interest (ROI) of 1-cm diameter on the delayed phase images. This region was considered the highest change in Hounsfield Units between the delayed and arterial phase images and represented the leakage of contrast medium into the hematoma. The same ROI circle was then drawn on the arterial phase CT image and the Hounsfield Units were measured. A change >10% in Hounsfield Units was considered a positive leakage sign, or hematoma expansion. A follow-up CT was performed 24 hours later where hematoma expansion was defined as >10% change in hematoma volume from the initial CT.

The authors found that the spot sign was positive in 18 (22%) of patients and that the leakage sign was positive in 35 (43%) of patients. 33 of the 35 patients with a positive leakage sign also had positive spot signs. Overall, leakage sign had a higher sensitivity and specificity than the spot sign: 93.3% and 88.9%, respectively, versus 77.8% and 73.8%. In addition, the leakage sign proved to be a better predictor of outcomes than the spot sign. Patients with a positive leakage sign had significantly poorer outcomes (20.0% versus 51.5%), but outcomes were unaffected in patients with a positive spot sign.

In conclusion, the leakage sign appears to be both an easy and reliable method to predict hematoma expansion in patients with ICH.