Differentiation Researches on the Meningioma Subtypes by Radiomics from Contrast-Enhanced Magnetic Resonance Imaging: A Preliminary Study.

BACKGROUND: Meningioma subtypes are one of the most common key points to the treatment and prognosis of patients. The purpose of this study was to investigate the differential diagnostic value of radiomics features on meningioma. METHODS: A total of 241 patients with meningioma who had undergone tumor resection were randomly selected including 80 with meningothelial meningioma, 80 with fibrous meningioma, and 81 with transitional meningioma. These meningiomas were divided into 4 groups including: meningothelial versus fibrous (group 1), fibrous versus transitional (group 2), meningothelial versus transitional (group 3), and meningothelial versus fibrous versus transitional (group 4). All patients were examined using the same magnetic resonance scanner (GE 3.0 T) and the preoperative contrast-enhanced T1-weighted images were available. Radiomics features from the contrast-enhanced T1-weighted images of 241 patients were evaluated by 2 experienced radiology specialists. RESULTS: A total of 385 radiomics features were extracted from the images of each patient. Several preprocessing methods were applied on the radiomics dataset to reduce the redundancy and highlight differences between different meningioma before the Fisher discrimination analysis was adopted and leave one out cross validation methods were used for the model validation. The differentiation accuracies of the Fisher discriminant analysis model for groups 1, 2, 3, and 4 were 99.4%, 98.8%, 100% and 100%, respectively; leave one out cross validation method was achieved for group 1, 2, 3, and 4 with the accuracies of 91.3%, 95.0%, 100%, and 94.2%, respectively. CONCLUSIONS: Radiomics features and the combined Fisher discriminant analysis could provide satisfactory performance in the preoperative differential diagnosis of meningioma subtypes and enable the potential ability for clinical application.

Medulloblastoma with Atypical Dynamic Imaging Changes: Case Report with Literature Review.

OBJECTIVE: We analyzed a case of medulloblastoma with atypical dynamic imaging changes retrospectively to summarize the atypical magnetic resonance imaging (MRI) features of medulloblastoma by reviewing the literature. METHODS: An atypical case of medulloblastoma in the cerebellar hemisphere confirmed by pathology was analyzed retrospectively, and the literature about it was reviewed. RESULTS: The radiologic findings of the patient were based on 3 examinations. The first examination showed that the cortex of the bilateral cerebellar hemisphere had diffuse nodular thickening, with a high signal on diffusion-weighted imaging and significant enhancement. Contrast enhancement MRI 1 year later showed the signal of cerebellar hemisphere returned to normal but revealed an enhanced nodule. A reexamination 6 months later showed an irregular mass with a high-density shadow in the cerebellar vermis on CT scan. The T2-weighted image revealed multiple degenerative cysts, and the mass had significant enhancement. CONCLUSION: The radiologic characteristics of atypical medulloblastomas vary in adults and children. Understanding the radiologic characteristics of medulloblastomas, such as MRI features, age of onset, and location of atypical medulloblastomas, can help improve the diagnosis of medulloblastomas.

Leukoencephalopathy with cerebral calcifications and cysts: clinical and pathological features in two adults.

Two adult patients diagnosed with Leukoencephalopathy with cerebral calcifications and cysts (LCC) were presented. Both patients had a long-term (8-10 years) following-up. Radiological findings of both patients revealed the characteristic signs of LCC: cerebral white matter abnormalities, calcifications, and cysts. In case 1, the initial CT scan showed a low-density area in the right frontal lobe and it had developed into a large cystic lesion after 8 years. Histopathological determination revealed that the cyst wall was associated with hemorrhage, angiomatous formation, and some Rosenthal fibers. In case 2, a major cystic lesion was located at the left parietal lobe which was resected and an old hematoma was found inside the cyst. Nine years later, the follow-up neuroimaging of case 2 showed a remarkable improvement of white matter abnormalities and cystic lesions. Hemorrhagic fluid was observed inside the cysts. Additionally, follow-up CT and MR scans showed a rapid enlargement of cystic lesions accompanied with hemorrhagic fluid levels after a year. Then, a major cyst was surgically removed to relieve pressure symptoms. Pathology of the resected cyst exhibited an organized hemorrhage inside the cyst and a large amount of hemosiderin surrounding the cyst wall. In conclusion, our two cases demonstrated that angiomatous changes subsequent with hemorrhage may be the major mechanism of cyst formation and development.

Recurrent unconsciousness due to bilateral middle cerebral artery stenosis.

Unconsciousness may be caused by transient ischemia of the bilateral hemisphere or brain stem. We report a case of recurrent unconsciousness in which angiography confirmed an occluded left middle cerebral artery (MCA) with well-established collateral compensation, along with a severely stenotic right MCA with poor collateral compensation, which was consistent with decreased cerebral blood flow and cerebral blood volume seen on a computed tomography perfusion study. A stent was placed in the patient's right MCA, after which the symptom disappeared completely. This case demonstrates that bilateral MCA stenosis may lead to recurrent unconsciousness through the mechanism of hypoperfusion.