Cerebral ventricular empyema associated with severe adult pyogenic meningitis: computed tomography findings

[Pathognomonic magnetic resonance imaging (MRI) finding of fluid-fluid level in pyogenic ventriculitis: two case reports]

Pyogenic ventriculitis is an uncommon and potentially fatal central nervous system infection. Delayed treatment due to non specific clinical symptoms may lead to an unfavorable outcome. Brain magnetic resonance imaging (MRI) plays an important role in the diagnosis of pyogenic ventriculitis. We describe two patients with pyogenic ventriculitis presenting with a pathognomonic MRI finding. The first patient, a 77-year-old female, developed high fever and consciousness disturbance. MR images revealed hyperintense lesions with a fluid-fluid level in the bilateral lateral ventricles on diffusion-weighted images (DWIs) and hypointense lesions on T2-weighted images (T2WIs). MR images also revealed findings of left otitis media. The second patient, a 63-year-old male, who had a past history of multiple myeloma and had received chemotherapy, developed high fever and left hemiparesis. MR images revealed a hyperintense lesion with a fluid-fluid level in the right lateral ventricle on DWIs and a hypointense lesion on T2WIs, multiple ring-enhancing lesions on gadolinium enhanced T1-weighted images, and pontine infarction on DWIs. Chest computed tomography revealed an infiltrative shadow in the lower lobe of the left lung. On the basis of MRI findings, both patients were diagnosed as having pyogenic ventriculitis and were administered high-dose meropenem intravenously. The second patient was also administered sulfamethoxazole-trimethoprim orally. Intraventricular abnormalities disappeared and the patients achieved complete remission after the antibacterial treatment. Intraventricular hyperintense lesions on DWIs and hypointense ones on T2WIs with a fluid-fluid level is a pathognomonic finding of pyogenic ventriculitis and has not been previously reported in other diseases. Recognition of the characteristic MRI features and initiation of high-dose and appropriate antibiotics in an early stage may lead to a favorable outcome of the disease.

Disproportionate correlation between imaging and outcome in an infant with cerebral abscess

Brain abscesses represent organized foci of suppuration within the parenchyma. In this paper, we describe the case of a 3-month old girl with a large, complicated cerebral abscess. In addition, the course of treatment is presented. The patient’s recovery was excellent. The follow-up MRI showed only subtle porencephalic changes as the only parenchymal sequels, which may have been due to central nervous system (CNS) plasticity in infants.

The value of different magnetic resonance imaging sequences for the detection of intraventricular hemorrhages*

PURPOSE

The aim of this study was to determine the value of different magnetic resonance imaging (MRI) sequences for the diagnosis of intraventricular hemorrhages (IVHs).

PATIENTS AND METHODS

The study included 22 consecutive patients with computed tomography (CT) proven IVH in which an MR examination had been performed. Proton-density-(PD-), T2-, fluid-attenuated inversion-recovery (FLAIR), T1- and T2*-weighted images were evaluated retrospectively by two neuroradiologists regarding presence and anatomical distribution of IVH, and cerebrospinal fluid (CSF) flow artifacts. CT was used as gold standard.

RESULTS

According to CT, IVH was located in the right/left lateral ventricles in 16/17 patients, in the third ventricle in seven and in the fourth ventricle in twelve cases. PD- and T2*-weighted images both showed a 100% sensitivity and specificity for the overall diagnosis of IVH, and a high sensitivity for the detection of IVH in all four ventricles. The sensitivity of T1-, T2- and FLAIR- weighted images for the overall presence of an IVH was 77%, 85%, and 93%, respectively, with specificities of 100%. CSF flow artifacts occurred predominantly in the third and fourth ventricles. While FLAIR- and T2-weighted sequences were especially prone to this phenomenon, T1-, T2*- and PD-weighted images showed a higher resistance to those artifacts.

CONCLUSION

This study demonstrates a high sensitivity of PD- and T2*-weighted images in the detection of IVH. On the contrary, T2-, T1- and FLAIR-weighted sequences were not suitable for a reliable detection of IVH.