Atypical Acute Hemorrhagic Leukoencephalitis (Hurst’s disease) Presenting with Focal Hemorrhagic Brainstem Lesion

Background  

Acute hemorrhagic leukoencephalitis (AHL; Hurst’s disease) is a rare, severe, inflammatory CNS disease that is typically diffuse, multifocal and associated with petechial hemorrhage. The objective of this study is to report the clinical, radiologic, and pathologic findings in a fatal AHL case with focal brainstem involvement and gross hemorrhage.     

Haemorrhagic and perivenous encephalitis: a clinical-pathological review of 38 cases.

Clinical and pathological data from eight cases of acute haemorrhagic leucoencephalitis (AHL) confirm the previously documented devastating features of this disease. Data from 30 cases of perivenous encephalitis (PVE) associated with viral diseases reveal pathological changes ranging from lymphocytic cuffing of vessels to severe vasculitis similar to the vasculitis of AHL. Relatively few cases show demyelination as a prominent feature. The pathological changes are unrelated to the type of underlying disease with the exception that the pathology of 'post-rubella' encephalitis tends to be mild. Two cases of rubeola and two of mumps showed viral nodules in the cortex, raising the possibility of direct viral invasion of tissue. Allowing for species differences, these changes are analogous to the pathological features of experimental allergic encephalitis (EAE); with the various pathological changes of PVE paralleling the features of ordinary EAE, while the changes of AHL and the severe cases of PVE strongly resemble hyperacute EAE.     

Computerized tomography as a diagnostic aid in acute hemorrhagic leukoencephalitis

Computerized tomography (CT) in a pathologically proven case of acute hemorrhagic leukoencephalitis (AHL) showed a mass effect and increased absorption coefficient in the right hemisphere within 18 hours of the onset of neurological symptoms. The changes corresponded to the site of white matter edema, necrosis, and petechial hemorrhages demonstrated postmortem. The early changes of CT reflect the hyperacute nature of AHL and differ from those of herpes simplex encephalitis.     

Recent Advances in Cerebellar Ischemic Stroke Syndromes Causing Vertigo and Hearing Loss

Cerebellar ischemic stroke is one of the common causes of vascular vertigo. It usually accompanies other neurological symptoms or signs, but a small infarct in the cerebellum can present with vertigo without other localizing symptoms. Approximately 11 % of the patients with isolated cerebellar infarction simulated acute peripheral vestibulopathy, and most patients had an infarct in the territory of the medial branch of the posterior inferior cerebellar artery (PICA). A head impulse test can differentiate acute isolated vertigo associated with PICA territory cerebellar infarction from more benign disorders involving the inner ear. Acute hearing loss (AHL) of a vascular cause is mostly associated with cerebellar infarction in the territory of the anterior inferior cerebellar artery (AICA), but PICA territory cerebellar infarction rarely causes AHL. To date, at least eight subgroups of AICA territory infarction have been identified according to the pattern of neurotological presentations, among which the most common pattern of audiovestibular dysfunction is the combined loss of auditory and vestibular functions. Sometimes acute isolated audiovestibular loss can be the initial symptom of impending posterior circulation ischemic stroke (particularly within the territory of the AICA). Audiovestibular loss from cerebellar infarction has a good long-term outcome than previously thought. Approximately half of patients with superior cerebellar artery territory (SCA) cerebellar infarction experienced true vertigo, suggesting that the vertigo and nystagmus in the SCA territory cerebellar infarctions are more common than previously thought. In this article, recent findings on clinical features of vertigo and hearing loss from cerebellar ischemic stroke syndrome are summarized.     

Acute hemorrhagic leukoencephalopathy: clinical and CT diagnosis and histopathological confirmation in an elderly patient

With the aid of CT acute hemorrhagic leukoencephalopathy (AHL) was diagnosed before death in a 65 year old woman. On the histopathological evidence, which is very similar to that for experimental allergic encephalomyelitis (EAE), AHL is considered to be a highly acute variant of parainfective encephalomyelitis.

---

Sommario In una donna di 65 anni, con l'ausilio della TAC, la diagnosi di leucoencefalite acuta emorragica è stata posta prima dell'exitus. Sulla base dei reperti istopatologici molto simili a quelli dell'encefalomielite allergica sperimentale, la leucoencefalite acuta emorragica viene interpretata come variante iperacuta di una encefalomielite parainfettiva.

     

Migraine prevalence in eating disorders and pathophysiological correlations

Acute hemorrhagic leukoencephalitis (AHL) is a rare demyelinating disease mainly affecting children, characterized by acute onset, progressive course and high mortality. A 62-year-old man was admitted to our Unit for diplopia and ataxia ensuing 2 weeks after the onset of pneumonia. MRI T2-weighted images showed signal hyperintensities in the brainstem. Antibodies against Mycoplasma Pneumoniae and cold agglutinins were found. Two weeks later the patient had a worsening of his conditions: he developed left hemiplegia with motor focal seizures and the day after he was deeply comatose (GCS = 4). A second MRI scan showed extensive hyperintensities involving the whole right hemisphere white matter with a small parietal hemorrhagic area. The clinical and neuroimaging features suggested the diagnosis of AHL, Aciclovir in association with steroid therapy were administered and then plasmapheresis was started. After 30 days of coma, the patient gradually reacquired consciousness and motor functions; anyway a left hemiplegia persisted.     

Diffusion imaging in traumatic brain injury

Traumatic brain injury is a common cause of death worldwide, affecting mostly young people. The most feasible examination to be performed in the emergency room is computed tomography. Magnetic resonance (MR) imaging is becoming a significant tool in the evaluation of severe brain trauma. Diffusion-weighted imaging is an advanced MR imaging sequence that has been used to detect areas of ischemia and tumor malignancy. This article describes the recent advances in trauma based on diffusion-weighted MR imaging findings and in brain injury from head trauma based on diffusion-weighted MR imaging and diffusion tensor MR imaging findings. Current and potential clinical applications are discussed.     

Transient magnetic resonance imaging abnormalities during partial status epilepticus

Magnetic resonance imaging is an important tool in the evaluation of patients with seizures. Frequently, abnormalities are found that lead to further, invasive testing. The first child with transient abnormal findings on magnetic resonance imaging during a time of frequent partial seizures is presented. This lesion disappeared with seizure control. The imaging literature is reviewed concerning transient findings on any imaging modality during frequent seizures. Caution in recommending invasive procedures is suggested when abnormalities are found on magnetic resonance imaging during frequent seizures.     

Atypical Imaging Evolution of Sturge-Weber Syndrome Without Facial Nevus

We report a patient with Sturge-Weber syndrome without facial angioma, who presented with seizures and normal initial imaging results. The patient experienced several years without seizures before a sudden increase in seizure frequency, followed by an atypical evolution of imaging findings prompting biopsy to establish the diagnosis. This case highlights not only the rare presentation of isolated leptomeningeal angiomatosis, but also the potential for atypical evolution of imaging findings through the course of the disease. We detail the imaging findings of our case and review the potential pathophysiological basis for this appearance. Our experience suggests that repeat imaging is warranted in patients with suspected Sturge-Weber syndrome or those with intractable cryptogenic epilepsy, because some imaging features of Sturge-Weber syndrome may manifest over time.     

Hypoxic-ischemic encephalopathy: correlation of serial MRI and outcome

Twenty-four patients with hypoxic-ischemic encephalopathy were examined with serial magnetic resonance imaging up to 4 years of age. Magnetic resonance imaging studies were performed in the neonatal period, at the fourth month and the fourth year of age, and the findings were compared with the patients' neurodevelopmental outcome at the fourth year of age. Periventricular signal alterations and deep gray matter involvement were usually evident in the initial magnetic resonance imaging studies, and encephalomalacia, periventricular leukomalacia, and atrophy were the common findings on follow-up magnetic resonance imaging studies. In the patients with hypoxic-ischemic encephalopathy, some correlation between magnetic resonance imaging findings and neurodevelopmental outcome was recognized. The patients with deep gray matter involvement on the initial magnetic resonance imaging had a poor prognosis, and the ones with normal magnetic resonance imaging findings had a favorable neurodevelopmental outcome. On the follow-up magnetic resonance imaging findings, encephalomalacia and periventricular leukomalacia were associated with poor neurodevelopmental outcome. In predicting the neurologic outcome at 4 years of age, magnetic resonance imaging findings of the neonatal period had the highest negative predictive value, whereas magnetic resonance imaging findings at 4 months of age and 4 years of age had the highest positive predictive value.     

Status Epilepticus and Periictal Imaging

Summary:  Peri- and postictal changes on both anatomic and functional imaging examinations have been recognized for many years. With the wide availability of magnetic resonance imaging and positron emission tomography, a growing range of recognized acute imaging findings have been described. Periictal and postictal findings can be classified as either local or remote, with respect to the site of maximal ictal EEG abnormality. Although many of the findings described are reversible, the factors that determine whether findings will resolve are incompletely understood. This article considers the range of findings that have been described, places them into the context of known or hypothesized pathophysiologic mechanisms, and considers their clinical significance. A framework is proposed for considering the relation between ictal duration and severity, the characteristics of imaging abnormalities, and the mechanism of their underlying pathophysiology.     

Extrathyroidal manifestations of thyroid disease: thyroid ophthalmopathy

Thyroid ophthalmopathy is a common autoimmune, inflammatory disease involving the orbit. Diagnosis is based on the clinical presentation and findings. Imaging, mainly CT and MR imaging, are helpful to reveal the extent of disease and degree of muscle enlargement and to evaluate for complications, such as optic nerve compression. This article reviews the basic pathology and pathophysiology of the disease and describes the extensive imaging findings on CT and MR imaging. The differential diagnosis of thyroid ophthalmopathy is reviewed.     

Autoimmune-mediated encephalitis and mimics: A neuroimaging review

Autoimmune encephalitis is a category of autoantibody-mediated neurological disorders that often presents a diagnostic challenge due to its variable clinical and imaging findings. The purpose of this image-based review is to provide an overview of the major subtypes of autoimmune encephalitis and their associated autoantibodies, discuss their characteristic clinical and imaging features, and highlight several disease processes that may mimic imaging findings of autoimmune encephalitis. A literature search on autoimmune encephalitis was performed and publications from neuroradiology, neurology, and nuclear medicine literature were included. Cases from our institutional database that best exemplify major imaging features were presented.     

Status epilepticus and periictal imaging

Peri- and postictal changes on both anatomic and functional imaging examinations have been recognized for many years. With the wide availability of magnetic resonance imaging and positron emission tomography, a growing range of recognized acute imaging findings have been described. Periictal and postictal findings can be classified as either local or remote, with respect to the site of maximal ictal EEG abnormality. Although many of the findings described are reversible, the factors that determine whether findings will resolve are incompletely understood. This article considers the range of findings that have been described, places them into the context of known or hypothesized pathophysiologic mechanisms, and considers their clinical significance. A framework is proposed for considering the relation between ictal duration and severity, the characteristics of imaging abnormalities, and the mechanism of their underlying pathophysiology.     

Emergency head & neck imaging: infections and inflammatory processes

Neck infections are fairly common in the emergency setting, affecting a broad spectrum of the patient population. Care should be taken not only to distinguish these conditions from other noninfectious origin such as malignancy but also to guide acute clinical management. A familiarity with neck anatomy, the imaging modalities used for investigation of such conditions, as well as common findings on imaging are critical to the care of affected patients. Cross-sectional imaging is a mainstay in this setting. This article presents the most common neck infections, and details some of their most prominent findings on cross-sectional imaging.     

The Many Faces of Cerebral Developmental Venous Anomaly and Its Mimicks: Spectrum of Imaging Findings

Developmental venous anomalies (DVAs) are the most common cerebral vascular malformations and are usually found incidentally on neuroimaging studies. Despite the benign nature of DVAs, occasionally, they can be symptomatic. The objective of this article is to review the spectrum of imaging findings of DVAs on conventional and advanced imaging studies. In addition, neuroimaging findings of symptomatic DVAs as well as imaging mimicks will also be described to assist in the approach to differential diagnosis.     

Ultrasound, computed tomography and magnetic resonance imaging in myopathies: correlations with electromyography and histopathology

Imaging of examinations by ultrasound (US), computerized tomography (CT) and low field magnetic resonance imaging (MRI) were compared with EMG and muscle biopsy findings in the same muscles of 33 patients with different neuromuscular diseases. None of the imaging methods revealed specific diagnostic details, but gave valuable information on the extent and distribution of muscle involvement. In myopathies all imaging modalities corresponded well with the EMG and histopathology findings, but in the neuropathies with minimal tissue destruction EMG was, understandably, more sensitive. The imaging characteristics of MR were as good as those of CT, but MRI has the advantage of not requiring ionizing radiation. US is the most economical method and it was found to be, despite its lower resolution, very informative in the hands of an experienced examiner, especially for the detection of fibrosis. The good agreement of histopathology with pathologic imaging and EMG findings implies that the accuracy of muscle biopsy increases, if its site is selected on the basis of imaging and/or EMG examination.     

Simultaneous typical and extraordinary imaging findings of AIDS-associated cytomegalovirus encephalitis

Encephalitis caused by cytomegalovirus (CMV) is a devastating disease that occurs mostly in profoundly immunocompromised individuals, particularly in the setting of advanced HIV infection or organ transplantation. Imaging findings in AIDS-associated cytomegalovirus encephalitis that have been described range from ventriculitis (more common) to solitary mass lesions (less common). We describe a fatal case of AIDS-associated cytomegalovirus encephalitis that included typical imaging findings but also atypical features with widespread, multifocal lesions demonstrating restricted diffusion on magnetic resonance imaging (MRI). It is likely that these diffusion abnormalities are appreciated due to changes in imaging technology from the pre-highly active antiretroviral therapy era in which the typical imaging findings of CMV encephalitis were first described. The differential diagnosis of widespread, multifocal lesions with restricted diffusion in the setting of AIDS should now include CMV encephalitis.     

Cysts and tumors of the oral cavity, oropharynx, and nasopharynx in children

A wide variety of developmental and neoplastic lesions arise in the oral cavity, oropharynx, and nasopharynx in children. The clinical manifestations and cross-sectional imaging findings provide complementary information, which is used to establish a probable or definitive diagnosis. This article describes imaging techniques and findings for developmental cystic masses and solid tumors in the pediatric population.