JOURNAL OF THE LOUISIANA STATE MEDICAL SOCIETY
Figure 3: A) Intraoperative image of the hemangioma with a lateral portion of the left lobe of the liver. B) Low-power view showing a well-circumscribed lesion composed of cavernous vascular channels in a background of normal liver parenchyma and zones of sclerosis (hematoxylin-eosin, original magnification x2).
performed. Non-contrast CT generally shows a hypodense, fairly well-circumscribed mass while contrast enhanced arterial phase images reveal a peripherally discontinuous pattern of enhancement. Images obtained in later phases usually show a pattern of enhancement that fills in from the periphery to the center. Ultimately, the enhancement pattern results in a lesion that is isodense, or hyperdense to the surrounding liver parenchyma and vascular structures.⁹ MRI findings of a typical hemangioma are homogenous on the T1-weighted series with a hypointense signal while the T2 signal is hyperintense, though not as intense compared to cerebrospinal fluid or hepatic cysts. MRI of the liver with intravenous contrast demonstrates a similar enhancement pattern to that seen on CT; specifically, there is a discontinuous, peripheral, and nodular enhancement that fills in centripetally on delayed phases.⁹ Nuclear medicine (SPECT) imaging typically demonstrates decreased radiotracer activity within hemangiomas on early perfusion images followed by increased activity on delayed blood pool images.⁹ Our patient’s mass had some imaging findings that were classic while others were inconsistent. On ultrasound, it was hypoechoic with well-circumscribed borders in certain areas, but there was no definitive fat plane visualized between the stomach and the spleen. There was also no internal vascularity identified definitively, raising questions about the diagnosis of a benign hemangioma. On CT, this lesion possessed most of the classic CT findings of enhancement in a nodular, discontinuous manner. However, it’s unusually large size meant the tumor filled very slowly with blood, so slow in fact that the entire tumor did not fill entirely with contrast on delayed imaging. Nuclear imaging red blood cell scan showed a much more classic appearance of low activity on the initial phase of injection followed by increased activity on delayed blood pool phase images.
DISCUSSION
Hemangiomas of the liver can be seen in up to 20% of the population, with most cases being benign, asymptomatic, and managed with observation.1 Those that are symptomatic usually present with abdominal pain often the result of stretching Glisson’s capsule or compression of adjacent organs.1 Other symptoms may include nausea, vomiting, jaundice, early satiety, or hemorrhage.³ For large symptomatic and growing hemangiomas of the liver, surgical management is the preferred modality of treatment and typically includes enucleation or a wedge excision.⁸ Pedunculated hemangiomas of the liver have a female predominance of 69% which is most likely attributable to increased estrogen exposure.¹ There is also a predilection for the left hepatic lobe (74% of cases), likely due to the large surface area to volume ratio of the left hepatic lobe compared to the right lobe.¹ Left lobe variants are particularly troublesome due to the risk of undergoing torsion and subsequent ischemia with resultant tissue necrosis. Imaging characteristics of hepatic hemangiomas vary, but there are several consistent and classic findings that aid in diagnosis. On ultrasound, they are usually hyperechoic with a heterogeneous echotexture and well-defined borders, although a small percentage appear hypoechoic in a background of hepatic steatosis. Doppler images more often show no internal or peripheral vascularity or color flow, a sign more worrisome for hepatocellular carcinoma.³ CT findings for most hemangiomas depend entirely on the utilization of intravenous contrast as well as the phase in which the study is being
126 La State Med Soc VOL 170 JULY/AUG 2018
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