Automated segmentation of ventricular volumes and subarachnoid hemorrhage from computed tomography images: Evaluation of a rule-based pipeline approach.

Changes in ventricular size, related to brain edema and hydrocephalus, as well as the extent of hemorrhage are associated with adverse outcomes in patients with subarachnoid hemorrhage (SAH). Frequently, these are measured manually using consecutive non-contrast computed tomography scans. Here, we developed a rule-based approach which incorporates both intensity and spatial normalization and utilizes user-defined thresholds and anatomical templates to segment both lateral ventricle (LV) and SAH blood volumes automatically from CT images. The algorithmic segmentations were evaluated against two expert neuroradiologists on representative slices from 20 admission scans from aneurysmal SAH patients. Previous methods have been developed to automate this time-consuming task, but they lack user feedback and are hard to implement due to large-scale data and complex design processes. Our results using automatic ventricular segmentation aligned well with expert reviewers with a median Dice coefficient of 0.81, AUC of 0.91, sensitivity of 81%, and precision of 84%. Automatic segmentation of SAH blood was most reliable near the base of the brain with a median Dice coefficient of 0.51, an AUC of 0.75, precision of 68%, and sensitivity of 50%. Ultimately, we developed a rule-based method that is easily adaptable through user feedback, generates spatially normalized segmentations that are comparable regardless of brain morphology or acquisition conditions, and automatically segments LV with good overall reliability and basal SAH blood with good precision. Our approach could benefit longitudinal studies in patients with SAH by streamlining assessment of edema and hydrocephalus progression, as well as blood resorption.

MRI of orbital cellulitis and orbital abscess: the role of diffusion-weighted imaging.

OBJECTIVE: Our aims were to describe the role of diffusion-weighted imaging (DWI) in detecting abscess as a complication of orbital cellulitis and to assess whether abscess can be diagnosed with a combination of conventional unenhanced sequences and whole-brain DWI with parallel acquisition. Nine cases of orbital cellulitis imaged with MRI were retrospectively reviewed, including six cases with pyogenic abscess. CONCLUSION: In this preliminary study, DWI improved diagnostic confidence in nearly all cases of orbital abscess when used in conjunction with contrast-enhanced imaging. DWI also confirmed abscess in a majority of cases without contrast-enhanced imaging, which may be of particular use when contrast material is contraindicated.

Synchronous moyamoya syndrome and ruptured cerebral aneurysm in Alagille syndrome.

Moyamoya syndrome and cerebral aneurysm formation are rare cerebrovascular manifestations of Alagille syndrome. Although previously reported in isolation, occurrence of these complications in a single patient has not been described. We report clinical and imaging features of synchronous moyamoya syndrome and ruptured cerebral aneurysm in a patient with Alagille syndrome.

Delayed response and survival from NovoTTF-100A in recurrent GBM.

We present a 48-year-old male with recurrent glioblastoma (GBM) who was enrolled in the NovoTTF-100A landmark phase III study and has been on device for >6 years. During this time, his magnetic resonance images demonstrated initial growth followed by a slow decrease in enhancement with continued residual disease. Long-term survivors in patients with recurrent GBM are rare, especially in the absence of definitive local treatment such as surgery or radiosurgery. We present the clinical, imaging and pathological findings for this patient in relation to use of the NovoTTF-100A device.

Prolonged activity of bevacizumab in adenocarcinoma of the lung with multiple brain metastases.

Patients with lung cancer having multiple brain metastases have poor outcomes. We present long-term disease treatment in a 60-year-old woman having greater than thirty brain metastases of NSCLC adenocarcinoma with a mutant allele of EGFR treated with differing chemotherapies including erlotinib, but disease response in the brain only with bevacizumab. Although initially restricted in use, increasing clinical reports have demonstrated safety of bevacizumab use in brain-involved cancer patients. Our case highlights that disease response to bevacizumab is similar in the brain to systemic disease and likely overcomes anatomical barriers that can limit other therapeutic agents.

Unusual CNS presentation of thyroid cancer.

As advanced therapies allow cancer patients to live longer, disease failure in the central nervous system increases from limited therapeutic penetration. Primary thyroid malignancies rarely metastasize to the brain and have a small number of investigations in literature on the subject. The majority of brain metastases involve the brain parenchyma, reflecting the mass and blood distribution within the brain and central nervous system. Here, we report two cases of the most common differentiated thyroid cancers; follicular thyroid cancer having brain involvement from extra-axial growth and papillary thyroid cancer having brain involvement from a single intraventricular metastasis, presumed as metastasis from the vascular choroid plexus. Both of our cases had widespread systemic involvement. For our follicular thyroid cancer, brain involvement was a result of extra-axial growth from cavarial bone, and our papillary thyroid cancer had brain involvement from a single intraventricular metastasis that was initially resected and nearly a year later developed extensive brain involvement. Unlike the usual gray-white junction metastases seen in the majority of metastatic brain tumors, including thyroid, our cases are uncommon. They reflect differences in tumor biology that allows for spread and growth in the brain. Although there is growing genetic knowledge on tumors that favor brain metastases, little is known about tumors that rarely involve the brain.