Striking MRI Changes of Focal Cortical Dysplasia Over Time: A Case Series and Literature Review.

PURPOSE OF REVIEW: Brain MRI findings of focal cortical dysplasia (FCD) can undergo dramatic changes over time, which may be related to long-term epilepsy or a combination of histopathologic changes that necessitate further investigation. RECENT FINDINGS: We describe 2 cases of FCD type IIb that initially displayed inconspicuous findings on MRI, however progressed to obvious signal changes on subsequent MRI 10-17 years later. Pathologic analysis indicates that the interval changes are likely attributed to reactive astrogliosis and diffuse parenchymal rarefaction. A few case reports and case series showing similar MRI changes have been described in the literature, the majority in pediatric patients. The adult cases we present add to the scientific evidence of these changes occurring in the adult population. SUMMARY: Our observations lead to several clinical suggestions, including closer interval follow-up imaging for nonlesional cases, the addition of postprocessing imaging methods, earlier surgical intervention, and meticulous surgical planning.

A unique variant of a right persistent hypoglossal artery arising from the common carotid artery with complex cardiovascular anomalies in a female neonatal patient.

Persistent primitive hypoglossal artery is a carotid-vertebrobasilar anastomosis, which commonly arises from the internal carotid artery at the level of the C (cervical) 1-3 vertebrae. We describe a unique case of a female infant patient with this anomaly that has an unusually low origin from the distal common carotid artery just below the bifurcation at the level of roughly C5 and supplies the entire vertebrobasilar system. Additional cardiovascular anatomical variations were present: Tetralogy of Fallot and a right-sided aortic arch with mirror image branching. These singular variations are rare in the general population, but even rarer when combined. Awareness of these unusual vascular variants is clinically significant, as they may predispose the patients to early ischemic injury, hemorrhage, aneurysm formation, and can be essential in surgical planning. Therefore, radiographic imaging is of importance in proper diagnosis of such variants.

Houdini Tumor: Case Report and Literature Review of Pregnancy-Associated Meningioma.

BACKGROUND: Meningiomas are common intracranial neoplasms of undetermined etiology. Accelerated growth during episodes of elevated serum estrogen and progesterone have been demonstrated in pregnant patients, as exhibited by an overexpression of estrogen or progesterone on immunohistochemical analysis. This case report and literature review describe a case of complete meningioma regression in a postpartum patient. CASE DESCRIPTION: A 23-year-old female presented at 37 weeks of pregnancy with 1-month history of fluctuating severe left-sided headaches, periodic blurry vision, nausea, and vomiting. She had 2 previous pregnancies without complication. Magnetic resonance imaging revealed a dural-based, heterogeneously enhancing mass along the left tentorium, just posterior to the transverse sinus, with supratentorial extension and surrounding edema. Differential diagnoses included meningioma versus hemangioma versus hemangiopericytoma. The patient followed up with neurosurgery 1 month after delivery. She had continued left-sided headaches but no longer complained of visual changes. A postpartum surgical resection via left occipital and suboccipital craniotomy was planned. Approximately 1 month later (now about 3 months after delivery) a repeat magnetic resonance imaging demonstrated a marked decrease in meningioma size, and the previously seen edema had resolved. In light of the sudden disappearance of the meningioma, no further surgical intervention was pursued. CONCLUSIONS: Because meningioma shrinkage or disappearance may occur after pregnancy, repeat imaging is advised as part of a preoperative evaluation. In addition, it is possible that an undetermined amount of meningioma removal surgeries may be avoided with further research into monitoring hormone levels connected to meningioma growth.

Propionibacterium acnes-associated neurosarcoidosis: A case report with review of the literature.

A 56-year-old woman with a 3-year history of hydrocephalus and ventriculo-peritoneal shunt placement, presented with worsening altered level of consciousness for 2 days. Imaging studies showed severe ventriculomegaly involving the lateral and third ventricles with multiple septated cysts noted in the lateral ventricles predominantly near the frontal horns. Histopathologic examination of the excised brain lesion revealed choroid plexus tissue and adjacent cerebral parenchyma with several non-caseating granulomas. Granulomatous inflammation was also identified in mediastinal lymph nodes. By using specific monoclonal antibodies, Propionibacterium acnes (P. acnes) were detected in non-caseating granulomas of both the brain and mediastinal lymph nodes. No acid-fast bacilli or fungal elements were present. To the best of our knowledge, this is the first demonstration of P. acnes in sarcoid granulomas of cerebral tissue, and it reinforces the possible link between P. acnes and sarcoidosis.

Acute Postviral Encephalopathy: Pathologic and Radiologic Correlation in an Atypical Case.

The authors report a case of fatal acute encephalopathy following influenza infection, with slightly atypical pathological and imaging findings. A healthy 8-year-old boy with probable recent influenza A/B infection admitted for refractory seizures was placed on phenobarbital coma and later developed hemodynamic instability. Magnetic resonance imaging revealed bilateral cerebral and cerebellar white matter lesions and microhemorrhages. Following his demise, the autopsy revealed a large area of necrosis in the right centrum semiovale with similar lesions in the temporal and cerebellar regions. Microscopically, there was extensive coagulative necrosis, compatible with necrotizing white matter encephalopathy, and neuronal loss suggesting superimposed hypoxic-ischemia. The acute progressive neurologic deterioration was partly reminiscent on acute necrotizing encephalopathy, a condition recently associated with influenza A. In acute necrotizing encephalopathy, typical brain findings are characterized by bilateral thalamic necrosis/petechiae with variable white matter edema. The somewhat atypical findings in our case can relate to superadded cardiovascular collapse and hypoxic-ischemic effects.

White matter microsusceptibility changes in patients with hepatic encephalopathy.

We report a new radiological finding in two patients with hepatic encephalopathy. A new susceptibility-weighted (SWI) magnetic resonance imaging sequence revealed multiple bilateral microsusceptibility changes in the corpus callosum and white matter, while the conventional T1 and T2 weighted images were unremarkable. We postulate that the etiology of the microsusceptibility changes may be related to hepatic coagulopathy and other factors, such as impaired cerebral blood flow and brain edema.