Characterization of indeterminate spleen lesions in primary CT after blunt abdominal trauma: potential role of MR imaging

Abstract

The purpose of this study was to determine the value of magnetic resonance imaging (MRI) for characterization of indeterminate spleen lesions in primary computed tomography (CT) of patients with blunt abdominal trauma. Twenty-five consecutive patients (8 female, 17 male, mean age 51.6 ± 22.4 years) with an indeterminate spleen lesion diagnosed at CT after blunt abdominal trauma underwent MRI with T2- and T1-weighted images pre- and post-contrast material administration. MRI studies were reviewed by two radiologists. Age, gender, injury mechanism, injury severity score (ISS), management of patients, time interval between CT and MRI, and length of hospital stay were included into the analysis. Patient history, clinical history, imaging, and 2-month clinical outcome including review of medical records and telephone interviews served as reference standard. From the 25 indeterminate spleen lesions in CT, 11 (44 %) were traumatic; nine (36 %) were non-traumatic (pseudocysts, n=5; hemangioma, n=4) and five proven to represent artifacts in CT. The ISS (P<0.001) and the length of hospital stay (P=0.03) were significantly higher in patients with spleen lesions as compared with those without. All other parameters were similar among groups (all, P>0.05). The MRI features ill-defined lesion borders, variable signal intensity on T1- and T2-weighted images depending on the age of the hematoma, focal contrast enhancement indicating traumatic pseudoaneurysm, perilesional contrast enhancement, and edema were most indicative for traumatic spleen lesions. As compared with CT (2/25), MRI (5/25) better depicted thin subcapsular hematomas as indicator of traumatic spleen injury. In conclusion, MRI shows value for characterizing indeterminate spleen lesions in primary CT after blunt abdominal trauma.

Comparison between MRI and CEUS in the follow-up of patients with blunt abdominal trauma managed conservatively

“…MRI, compared with CE-CT, is also able to better depict subcapsular hematoma, which is an indicator of traumatic injury, appearing as a hyperintense layer on T2-weighted sequences; it can also demonstrate vascular lesions, such as pseudoaneurysms, as a focular, nodular hyperintense lesion in arterial phase [17]; a splenic infarction, appearing as a hypointense image with a hyperintense edge without contrast enhancement; finally, it can easily demonstrate the presence of scars as hypointense linear or branched streaks with capsular retraction, as showed in our study.…”

“…showed [14][15][16][17]. Infact, the interpretation of traumatic lesions in MRI requires a huge knowledge of the different stages of blood in the various sequences, responsible of specific imaging findings.…”

Necessity of Immediate MRI Imaging in the Acute Care of Severely Injured Patients

“…He also mentioned that there are currently no guidelines for the diagnostic use of MRI in severely injured pediatric patients [ 15 ]. Gordic et al were able to describe a positive benefit of MRI diagnostics in the diagnosis of traumatic splenic lacerations [ 16 ].…”