Isolated axial lateropulsion caused by an acute lateral medullary infarction involving the dorsal spinocerebellar tract: A case report.

Lateral medullary syndrome encompasses a broad spectrum of symptoms and signs depending on the bulbar localization of the lesion. Body lateropulsion (BL) can occur without vestibular and cerebellar symptoms, as a unique manifestation of a lateral medullary infarction. However, it is relatively rare and challenging to diagnose. We report a case of a 72-year-old woman who presented with a tendency to fall to the right. She denied having vertigo, cerebellar signs, sensory loss, or motor weakness. No signs of vestibular dysfunction were found on the ENT examination. Neurological evaluation was unremarkable, except for mild ataxia of the right limbs along with BL to the right side when standing and walking. Brain magnetic resonance (MR) imaging showed an acute small infarct in the right lateral aspect of the medulla extending from the rostral to the caudal level. MR angiography found no stenosis or vascular occlusions. We believe that ipsilateral axial lateropulsion shown by our patient may be related to a selective ischemic lesion of the dorsal spinocerebellar tract in its medullary course. A lateral medullary infarction should be seriously considered in patients who present with isolated BL without further signs of bulbar involvement.

Forgetting the Unforgettable: Transient Global Amnesia Part II: A Clinical Road Map.

Transient global amnesia (TGA) is a clinical syndrome characterized by the sudden onset of a temporary memory disorder with profound anterograde amnesia and a variable impairment of the past memory. Usually, the attacks are preceded by a precipitating event, last up to 24 h and are not associated with other neurological deficits. Diagnosis can be challenging because the identification of TGA requires the exclusion of some acute amnestic syndromes that occur in emergency situations and share structural or functional alterations of memory circuits. Magnetic Resonance Imaging (MRI) studies performed 24-96 h after symptom onset can help to confirm the diagnosis by identifying lesions in the CA1 field of the hippocampal cornu ammonis, but their practical utility in changing the management of patients is a matter of discussion. In this review, we aim to provide a practical approach to early recognition of this condition in daily practice, highlighting both the lights and the shadows of the diagnostic criteria. For this purpose, we summarize current knowledge about the clinical presentation, diagnostic pathways, differential diagnosis, and the expected long-term outcome of TGA.

Forgetting the Unforgettable: Transient Global Amnesia Part I: Pathophysiology and Etiology.

Transient global amnesia (TGA) is a clinical syndrome characterized by the sudden onset of a temporary memory disorder with a profound anterograde amnesia and a variable impairment of the past memory. Since the first description, dating back over 60 years, several cases have beenreported in the literature. Nevertheless, TGA remains one of the most mysterious diseases in clinical neurology. The debate regarding the etiology of this disease has focused mainly on three different mechanisms: vascular (due to venous flow changes or focal arterial ischemia), epileptic, and migraine related. However, to date there is no scientific proof of any of these mechanisms. Furthermore, the demonstration by diffusion-weighted MRI of lesions in the CA1 field of the hippocampus cornu ammonis led us to hypothesize that the selective vulnerability of CA1 neurons to metabolic stress could play a role in the pathophysiology of TGA. In this review, we summarize current knowledge on the anatomy, vascularization and function of the hippocampus. Furthermore, we discuss the emerging theories on the etiology and the pathophysiological cascade leading to an impairment of hippocampal function during the attacks.

The role of unhenanced CT in a ruptured parathyroid adenoma: A case report.

Acute bleeding is a rare and potentially life-threatening complication of a Parathyroid Adenoma described in just a few cases in literature. We describe the case of a healthy 53-years-old female patient without prior history of parathyroid pathology who presented with acute onset of neck and mediastinal hemorrhage. Ultrasound (US), Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) combined with laboratory tests led to the diagnosis of a bleeding Parathyroid adenoma. This case is presented to sensitize both Radiologists and Clinicians about this rare presentation that should be put into differential diagnosis of acute neck swelling and pain.

Is This Truly A "Leave-Me-Alone" Lesion? An Unusual Case of Multiple Ring-shaped Lateral Ventricular Nodules.

BACKGROUND: Ring-shaped lateral ventricular nodules (RSLVNs) are commonly considered as benign asymptomatic lesions, which are sporadically detected as incidental findings on routine brain magnetic resonance imaging scans. Despite their not irrelevant frequency, the exact biological nature of these lesions remains largely unknown due to the lack of histopathologic studies. Here we present the clinical, neuroradiologic, and histopathologic findings of an unusual case of symptomatic multiple RSLVNs. CASE DESCRIPTION: A 44-year-old otherwise healthy man presented with a recent history of headache and retching. Neuroradiologic imaging revealed the presence of multiple RSLVNs, the largest of which, located in the cella media of the right lateral ventricle, exerted a mild to moderate mass effect on adjacent brain parenchyma. This latter nodule was successfully removed, with complete resolution of the symptoms. Histopathology revealed glial differentiation, and the specimen was diagnosed as subependymoma. CONCLUSIONS: This report provides novel evidence characterizing RSLVNs as possible variants of subependymoma with a peculiar imaging appearance, also suggesting that, like subependymomas, they may occasionally grow large enough to cause mass effect-related symptoms, thus requiring neurosurgical intervention.

Spontaneous emphysematous osteomyelitis of the spine: A case report.

Spontaneous emphysematous osteomyelitis of the spine is a very rare but severe condition caused by gas-forming microorganisms. We present the case of a 41-year-old obese male patient presenting at the Emergency Department with diabetic ketoacidosis, fever, and difficulty in walking. computed tomography and magnetic resonance imaging of the spine revealed bone marrow edema and intraosseous gas collections at the level of the fourth and fifth lumbar metameres, suggesting an osteomyelitis sustained by gas-forming microorganisms, which was then confirmed by the isolation of Klebsiella pneumonia in blood culture. Imaging plays a central role for the diagnosis of emphysematous osteomyelitis: the presence of multiple intraosseous gas collections of variable size, especially in patients with specific risk factors, is highly suggestive of an infection caused by gas-forming pathogens. Being familiar with this peculiar neuroradiological appearance is essential to ensure an early diagnosis and a timely antimicrobial therapy, which can considerably ameliorate the prognosis.

Solitary Cerebral Metastases vs. High-grade Gliomas: Usefulness of Two MRI Signs in the Differential Diagnosis.

BACKGROUND/AIM: The differentiation between cerebral metastases (CM) and high-grade gliomas (HGG) can be difficult on magnetic resonance imaging (MRI). The aim of this study was to evaluate the usefulness of searching two MRI signs (signal alteration in the adjacent cortex, SAAC, and peripheral rim sign, PRS), in order to distinguish between these entities. PATIENTS AND METHODS: A total of 61 patients were retrospectively enrolled (28 HGG, 33 CM). Fluid Attenuated Inversion Recovery (FLAIR) sequences were used to assess SAAC and contrast-enhanced T1-weighted sequences for PRS. RESULTS: A positive SAAC sign was present in 61% of HGG, and 12% of CM. Conversely, in SAAC-negative lesions, PRS was observed in 78% of CM and in 32% of HGG. Their association had a higher frequency in HGG than in the CM group (21 vs. 3%). CONCLUSION: While SAAC is specific for HGG and PRS, in the absence of SAAC, is relatively specific for CMs, their combined presence is highly suggestive of HGG.

Reversible MR Findings in Marchiafava-Bignami Disease.

Marchiafava-Bignami Disease (MBD) is a toxic demyelinating disease often diagnosed in chronic alcoholics. The disease process typically involves the corpus callosum and clinically presents with various manifestations resulting in MBD type A and type B on the basis of clinical condition, extent of callosal involvement and extracallosal involvement at brain magnetic resonance imaging (MRI), and prognosis. The death rate is high. We report a patient affected by MBD type B, who presented an isolated reversible splenial lesion at brain MRI and achieved a favorable recovery.

Subdural Hematoma as a Consequence of Labor Epidural Analgesia.

Subdural hematoma (SDH) following labor epidural analgesia is a rare neurological complication. SDH is a late complication of this procedure; it is caused by a leak of cerebrospinal fluid that may damage the vascular structures of the brain. Persistent headache in the days after labor epidural analgesia is a nonspecific clinical symptom caused by hematoma. Preexisting vascular malformations can be a concomitant cause of headache. Clinical cases have been reported even after epidural anesthesia. The differential diagnosis includes unspecified headache, sinusitis headache, drug-induced headache, cortical vein thrombosis, fistula of the dura mater, and bacterial, viral, and aseptic meningitis.

Magnetic resonance features of pyogenic brain abscesses and differential diagnosis using morphological and functional imaging studies: a pictorial essay.

The aim of this paper is to illustrate the potential of magnetic resonance imaging (MRI) in diagnosis, differential diagnosis, treatment planning and evaluation of therapy effectiveness of pyogenic brain abscesses, through the use of morphological (or conventional) and functional (or advanced) sequences. Conventional MRI study is useful for the identification of lesions, to determine the location and morphology and allows a correct hypothesis of nature in the most typical cases. However, the differential diagnosis from other brain lesions, such as non-pyogenic abscesses or necrotic tumors (high-grade gliomas and metastases) is often only possible through the use of functional sequences, as the measurement of diffusion with apparent diffusion coefficient (DWI-ADC), proton magnetic resonance spectroscopy ((1)H-MRS) and perfusion weighted imaging (PWI), which complement the morphological sequences and provide essential information on structural, metabolic and hemodynamic characteristics allowing greater neuroradiological confidence. Modern diagnostic MRI of pyogenic brain abscesses cannot be separated from knowledge, integration and proper use of the morphological and functional sequences.

Perfusion and spectroscopy magnetic resonance imaging in a case of lymphocytic vasculitis mimicking brain tumor.

BACKGROUND: Lymphocytic vasculitis of the central nervous system is an uncommon subtype of primary angiitis of the central nervous system (PACNS) - a rare inflammatory disorder affecting parenchymal and leptomeningeal arteries and veins. CASE REPORT: Establishing diagnosis on the basis of neuroimaging only is difficult, as it can mimic a brain tumor. Thus, histological diagnosis is essential for appropriate management. We present a case of biopsy-proven lymphocytic vasculitis mimicking a brain tumor on neuroimaging that was subsequently successfully treated with steroid therapy. We also discuss the findings in perfusion MR (PWI) and MR spectroscopy (MRS). CONCLUSIONS: Regional hypoperfusion on PWI and elevation of glutamate and glutamine levels on MRS (without associated typical tumor spectra) are common findings in inflammatory disorders, including PACNS, and can be useful in differential diagnosis with tumors.

Pontine extension of a tentorial schwannoma without cranial nerve involvement: a case report.

INTRODUCTION: Intracranial schwannomas unrelated to the cranial nerves are uncommon. We report a new case of tentorial schwannoma unrelated to the cranial nerves, with extension into the pons. A literature review with discussion of the most relevant pathogenetic aspects is also performed. CASE PRESENTATION: A 42-year-old Caucasian man was admitted with right-sided paresthesias and weakness of his upper and lower extremities. The neurological examination revealed right hemiparesis and hemi-hypoesthesia. A brain magnetic resonance imaging scan revealed a cerebellopontine lesion, arising from the left free edge of the tentorium, and extending into his pons. A piecemeal removal was performed through a retrosigmoid approach. The lesion was not found to be associated with any cranial nerves. The histological examination revealed a schwannoma Antoni type A. His postoperative course was uneventful. At one year follow-up, the patient was neurologically intact and the magnetic resonance imaging of his brain performed at that time showed complete removal without signs of recurrence. CONCLUSION: Tentorial schwannomas are rare clinical entities. Knowledge of their clinical, radiological and anatomical characteristics is very important for the correct diagnosis and management.

Pyogenic abscess from Providencia stuartii mimicking necrotic tumour at perfusion-weighted imaging.

The purpose of this case report is to increase the knowledge about magnetic resonance spectrum of pyogenic abscesses of the brain. A 74-year-old woman presented with a left frontal lobe cystic mass, developed in the site of post-traumatic contusions after surgical evacuation of a subdural hematoma. MR imaging showed an ipsilateral mass lesion with a thin, regular rim of T1 high-intensity signal, T2 low-intensity signal, and gadolinium-enhancement. Diffusion-weighted imaging with measure of apparent diffusion coefficient value showed inhomogenous diffusion restriction in the lesion core. Perfusion-weighted imaging (PWI) demonstrated high relative cerebral blood volume (rCBV) in both the lesion wall and perilesional area, with a maximal rCBV ratio (rCBV of the lesion/rCBV of the normal contralateral white matter) of 5.65 and 0.58, respectively. As a result, surgery and pathology showed a pyogenic abscess. Cultures grew were Providencia stuartii species. In conclusion, a pyogenic brain abscess from P. stuartii may show high rCBV at PWI, thus mimicking a necrotic tumour.

Differential diagnosis by unenhanced FLAIR T2-weighted magnetic resonance images between solitary high grade gliomas and cerebral metastases appearing as contrast-enhancing cortico-subcortical lesions.

The aim was to assess the value of unenhanced fluid-attenuated inversion recovery T2-weighted sequences (FLAIR-T2) in the differential diagnosis between solitary high-grade gliomas (HGG) and cerebral metastases (CM) appearing as contrast-enhancing cortico-subcortical lesions of the brain. In 69 patients with a contrast-enhancing cortico-subcortical brain lesion (43 HGG, and 26 CM), unenhanced FLAIR-T2 and gadolinium-enhanced FLAIR T1-weighted (Gd-FLAIR-T1) axial images have been reviewed for the involvement of the cortex adjacent to the contrast-enhancing lesion. In 27 (62.79%) out of 43 HGG, and 3 (11.53%) out of 26 CM, the cortex adjacent to the contrast-enhancing lesion showed high signal intensity on unenhanced FLAIR-T2 without enhancement at Gd-FLAIR-T1. Fischer's exact probability test was P = 0.0003 when applied to HGG versus CM categories, indicating a significant difference. The high signal intensity on unenhanced FLAIR-T2 without gadolinium-enhancement of the cortex adjacent to the enhancing lesion is more frequently associated with HGG than CM.

Regression of dilated perivascular spaces of the brain.

PURPOSE: Perivascular, or Virchow-Robin, spaces of the brain represent interstitial fluid-filled spaces continuous with subpial spaces, and not invagination of cerebrospinal fluid-filled subarachnoid spaces. Regression of a dilated, or even giant, perivascular space occurs rarely. The purpose of this paper is to describe magnetic resonance imaging evidence of complete regression of dilated perivascular spaces (dPVSs). METHODS: Patient 1 was a 76-year-old woman with right hemiparesis and aphasia from a left cranial vault meningioma infiltrating the superior sagittal sinus, and a left temporal lobe giant perivascular space. Patient 2 was a 70-year-old man with pituitary apoplexy, vasospasm, cerebral ischemia, and two dPVSs, one in the right temporal lobe, and one in the left anterior perforate substance. Patient 3 was a 78-year-old man with a generalized seizure, and a right temporal lobe dPVS. RESULTS: In all the patients, temporal lobe giant or dPVSs underwent regression, following meningioma subtotal resection (patient 1) or pituitary lesion shrinkage (patient 2), or spontaneously (patient 3). In patient 2, the left anterior perforate substance dPVS was unchanged. CONCLUSIONS: Temporal lobe giant or dPVSs may regress, eventually together with resection or regression of intracranial tumors, also distant from the PVSs. Cerebral edema does not seem the only factor influencing dilatation of PVSs.

Reversible post-traumatic bilateral extensive restricted diffusion of the brain. A case study and review of the literature.

PRIMARY OBJECTIVE: To increase the knowledge about diffuse traumatic brain injury (TBI) by reporting the magnetic resonance imaging (MRI) findings observed in a patient with reversible extensive restricted diffusion of the brain at diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps. CASE STUDY: An 18-year-old patient was admitted after high-energy closed TBI. Glasgow Coma Scale score was 4. Head computed tomography showed small left frontal and temporal haemorrhagic contusions and a small haemorrhage in the left thalamus. Ten days later, brain MRI showed diffuse high-signal intensity on T2-weighted images and DWI and restricted diffusion in the subcortical white matter of both centri semiovali, genu and splenium of corpus callosum and parietal cortex bilaterally (mean ADC value = 0.434-0.811 x 10(-3) mm(2) s(-1)). Eleven days later, follow-up brain MRI showed gliotic changes in the left splenium of corpus callosum, a clearcut decrease of T2-weighted high-signal intensity and resolution of abnormalities at DWI and ADC maps in all other involved sites. This was confirmed 36 days later. Three months later, the patient did not show neurological, cognitive or neuropsychiatric deficits. CONCLUSIONS: In the patient reported herein, closed TBI most likely induced diffuse excitotoxic injury of the brain which resulted in mainly reversible cytotoxic or intramyelinic oedema.

Intracranial involvement in plasmacytomas and multiple myeloma: a pictorial essay.

INTRODUCTION: The purpose of this pictorial essay is to increase awareness of the clinical presentation, neuroradiological findings, treatment options, and neuroradiological follow-up of plasmacytomas and multiple myeloma with intracranial growth. METHODS: This pictorial essay reviews the clinical features and neuroradiological findings in seven patients (four women, three men; age range at diagnosis 62-82 years) followed in two institutions. Six patients, one with IgG-kappa plasmacytoma, and five with IgG-kappa (n = 3), IgG-lambda (n = 1), and nonsecretory (n = 1) multiple myeloma, had been seen over a period of 9 years in one institution, and the other patient with IgG-kappa plasmacytoma had been seen over a period of 3.5 years in the other. RESULTS: Intracranial involvement is rare, most frequently resulting from osseous lesions in the cranial vault, skull base, nose, or paranasal sinuses. Primary dural or leptomeningeal involvement is rarer. Some typical findings of a dural and/or osseous plasmacytoma include iso- to hyperdensity on CT scan, T1 equal to high signal intensity and T2 markedly hypointense signal on MRI, and high vascularity possibly documented on intraarterial digital subtraction angiography. However, the neuroradiological findings generally lack specificity, since they are generally no different from those of meningioma, metastasis, lymphoma, dural sarcoma, plasma cell granuloma, infectious meningitis, and leptomeningeal carcinomatosis. CONCLUSION: The spectrum of clinical and neuroradiological evaluation shows that intracranial involvement from plasmacytoma and multiple myeloma must be taken into account in the differential diagnosis of cranial osseous and meningeal disease.