Predicting posttraumatic epilepsy with MRI: prospective longitudinal morphologic study in adults.

PURPOSE: Evaluation of morphologic risk factors for posttraumatic epilepsy (PTE) by using brain magnetic resonance imaging (MRI) in serial assessments

Karyometric features of low and high grade glial tumors as compared with their MRI appearance.

OBJECTIVE: To compare the results of a magnetic resonance imaging (MRI) grading designed to identify low and high grade gliomas with karyometry used as a tool to grade primary brain tumors. STUDY DESIGN: A consecutive series of 23 primary brain tumors was selected for this study. The neuroradiologist, not knowing the histologic diagnoses, divided the cases into low and high grade categories on the basis of the following 7 features: border sharpness, heterogeneity without contrast, cavitation, contrast enhancement, hypervascularity, mass effect and perifocal T2 hyperintensity. To each feature was given a numerical value, ranging from 1 to 3. All the cases were reviewed and classified by the same pathologist, blinded to the MRI diagnosis. Two hundred nuclei per case were recorded, and 93 karyometric features related to nuclear area, total optical density and chromatin distribution were analyzed for each nucleus. Statistical analysis included discriminant analysis, Kruskal-Wallis test, nonsupervised learning algorithm P-index and Beale statistic. RESULTS: Ten cases were classified as low grade on the basis of their MRI features. The corresponding histopathologic diagnoses were: grade 2 astrocytoma in 2 cases and grade 2 oligodendroglioma in 8 cases. An MRI diagnosis of high grade tumor was made in 13 cases. In 10 cases it was confirmed by the histopathologic diagnosis (3 grade 3 astrocytomas, 1 grade 3 oligodendroglioma and 6 glioblastomas). In the remaining 3 cases the histologic examination revealed a low grade tumor, 1 grade 2 astrocytoma and 2 grade 2 oligodendrogliomas. For the purposes of the karyometric analysis the cases were allocated to the low or high grade category according to their histologic diagnosis (13 cases low grade and 10 cases high grade). Nuclei from low and high grade tumors showed clearly different karyometric characteristics. The oligodendroglioma nuclei had abnormality values close to the low grade standard, while the astrocytoma nuclei were a highly dispersed group with characteristics indicative of a higher degree of nuclear abnormality than the oligodendroglioma nuclei. The results of karyometric analysis showed that grade 2 tumors, corresponding to the low grade group, form a rather distinct category from grade 3 and 4 tumors belonging to the high grade group. CONCLUSION: The results of MRI grading based on a series of features that are routinely assessed by the neuroradiologist to reach a final diagnosis correlate highly with the histopathologic diagnosis. Karyometry can be a useful adjunct to histologic grading.

Resolution of limbic encephalitis with detection and treatment of lung cancer: clinical-radiological correlation.

Paraneoplastic limbic encephalitis may develop in the setting of an otherwise occult malignancy. In the case reported here, the neuropsychiatric syndrome resolved with treatment of the underlying, previously undiagnosed small-cell lung cancer, and MR imaging showed resolution of the characteristic temporal lobe signal abnormalities.

Gemella morbillorum deep brain abscess successfully treated with combined stereotactic, medical, and imaging approach.

A rare case of brain abscess due to Gemella morbillorum, a normal inhabitant of the oral cavity, is presented. The aim of this report is to draw the attention of radiology literature readers to this little known pathogen, which caused a potentially life-threatening condition in an immunocompetent young man, and to emphasise the usefulness of a combined stereotactic, medical, and imaging approach to deep-located brain abscesses.

Mycotic aneurysms as lethal complication of brain pseudallescheriasis in a near-drowned child: a CT demonstration.

Intracranial true mycotic aneurysms are rare and generally lethal. We report a case of a near-drowned child with brain abscesses due to Pseudallescheria boydii, a saprophytic fungus, who died after subarachnoid hemorrhage occurred. CT showed contrast-enhancing lesions indicative of aneurysms of basilar and right posterior cerebral arteries that could not be appreciated 2 days before. P. boydii is often resistant to commonly used antimycotic drugs. Because CNS infection is frequently associated with near-drowning, early diagnosis and specific therapy are strongly recommended for these patients.

Expanding experience with spontaneous dermoid rupture in the MRI era: diagnosis and follow-up.

With widespread use of CT and MR imaging, experience with spontaneous dermoid rupture has significantly increased. What was previously believed to be a generally severe or even fatal accident, being the diagnosis made either at surgery or autopsy, or in patients with such consequent conditions as chemical meningitis or obstructive hydrocephalus, now appears to be more frequent than previously thought, and there is some evidence that it may also cause only a slight symptomatology or even be quite asymptomatic. We reviewed the clinical and imaging data of our series of five patients with spontaneously ruptured dermoids, spinal in one case, and intracranial supratentorial in four. These had their diagnosis following mild symptoms (number two cases) or incidentally (number two cases); the spinal tumor caused acute bladder dysfunction, possibly while undergoing rupture, and was associated with indolent intracranial fat spread. Three of the patients also had MR demonstration of asymptomatic persistence of fat spread in the subarachnoid spaces, respectively, 3, 4, and 5 years after rupture. One of the five cases, concerning a parasellar dermoid followed up over 6 years, provides the first demonstration of MR signal intensity change of the tumor prior to rupture.

MRI assessment of post-traumatic spinal instability.

The imaging evaluation of patients with spinal trauma has evolved over the past decades, and there has been particular interest in the concept of instability, to predict which a series of criteria have been proposed. We retrospectively evaluated the magnetic resonance imaging (MRI) findings in 50 patients with post-traumatic spinal instability according to Denis's three-column method, Daffner et al.'s radiographic criteria, and Oner et al.'s categorization of MRI findings; additionally, we evaluated the cord, the prevertebral tissue, and the epidural space. We suggest that an integrated panel of MRI information might be standardized in order to provide a more complete evaluation of spinal injury in an individual case and help planning surgical treatment.