An unusual Erdheim-Chester disease with orbital involvement: A case report

Erdheim-Chester disease is a rare non-Langerhans cell histiocytosis with multiorgan involvement and a specific tropism for perivascular and fatty connective tissue, of unclear origin, with poor response to therapy. Its identification is difficult because of the variable clinical presentation and its lack of knowledge. We report the case of a 63-years-old woman, with a history of bilateral orbital pseudotumor, who comes to our attention because of progressively worsening asthenia, vomiting and systemic inflammation. Total body computerized tomography scan showed a volumetric increase of choroid plexus of the temporal horn of the left lateral ventricle, presence of solid retrobulbar tissue at the level of both maxillary sinuses, lung fibrosis, and retroperitoneal and peri-aortic infiltration. The association of these signs addressed to a diagnosis of Erdheim-Chester disease. Thus, although extremely rare, the diagnosis of Erdheim-Chester disease must be considered in the case of bilateral retro-orbital tumors and multisystemic involvement

Value of serial magnetic resonance imaging in the assessment of brain metastases volume control during stereotactic radiosurgery

To evaluate brain metastases volume control capabilities of stereotactic radiosurgery (SRS) through serial magnetic resonance (MR) imaging follow-up

Circuit dissection of the role of somatostatin in itch and pain

Stimuli that elicit itch are detected by sensory neurons that innervate the skin. This information is processed by the spinal cord; however, the way in which this occurs is still poorly understood. Here we investigated the neuronal pathways for itch neurotransmission, particularly the contribution of the neuropeptide somatostatin. We find that in the periphery, somatostatin is exclusively expressed in Nppb+ neurons, and we demonstrate that Nppb+somatostatin+ cells function as pruriceptors. Employing chemogenetics, pharmacology and cell-specific ablation methods, we demonstrate that somatostatin potentiates itch by inhibiting inhibitory dynorphin neurons, which results in disinhibition of GRPR+ neurons. Furthermore, elimination of somatostatin from primary afferents and/or from spinal interneurons demonstrates differential involvement of the peptide released from these sources in itch and pain. Our results define the neural circuit underlying somatostatin-induced itch and characterize a contrasting antinociceptive role for the peptide

“The importance of being external”: review of the literature of the rare phenomenon of common carotid occlusion with bulb reverse-crossed stenosis and external collaterals activation. Is still correct speaking about carotid steal?

Common carotid artery occlusion (CCAO) is a rare phenomenon associated with the development of neurological symptoms. In CCAO, diversion of blood flow from the external carotid artery (ECA) to the internal carotid artery (ICA) via the carotid bulb (CB) may occur. This pathway activation has been called "carotid steal". Starting from a particular case we describe the ECD finding of a complete occlusion of CCA with patency of ICA and ECA. In case of occlusion of CCA, inversion of the ECA flow may occur, towards the ICA, and it can be damped by a significant stenosis crossed in retrograde direction that may concur to maintain the pressure balance between the two circulations. Usually, this particular compensation can guarantee normal flow velocities in middle cerebral arteries without signs of activation of anterior collateral pathways. In this review we underline the protective role of ECA and we propose a new definition for this phenomenon. The ECA may provide blood to the cerebral circulation through several anastomotic secondary channels. Finally, only with an extensive knowledge of hemodynamic information of all intracranial and extracranial arteries, including ECA, we can estimate cerebral ischemic risk of the patient and choose the correct management of this occlusion

HIPPOCAMPAL REVERSIBLE LESIONS IN A CASE OF TRANSIENT GLOBAL AMNESIA

PURPOSE: We present a case of transient global amnesia (TGA) onset in a 52-year-old male with a medical history of migraine. METHODS: Patient was taken to ER by his colleagues which reported that after an emotional stress he suddenly appeared perplexed and started asking repetitive questions. In ER a neurological examination excluded other neurological signs or symptoms and it was confirmed that cognitive impairment was limited to the amnesia domain; electroencephalography was unremarkable and he had no history of epileptic seizures or head trauma. At the neurologic examination Capland and Hodges criteria were fulfilled and the diagnostic hypothesis of TGA was placed. He underwent to a brain CT (Siemens SOMATOM Definition AS+ 128) and later he underwent to a brain MRI (GE Signa HDxt 1,5T). MRI protocol includes sagittal and axial T2w Fast Recovery Fast Spin Echo (FRFSE), axial and coronal T2w FLuid attenuated Inversion Recovery (FLAIR), axial T1w Fast Spin Echo (FSE), axial T2*w Gradient Echo (GE) and axial Echo-Planar Diffusion Weighted Imaging (EP-DWI, using a b value of 0 and 1000s/mm2). RESULTS: Brain CT and conventional MRI sequences did not show any relevant pathological findings but diffusion weighted imaging (DWI) showed two small areas of restricted diffusion in the right hippocampus. The amnesic syndrome resolved spontaneously within 24h; in a brain MRI follow-up performed two week later those findings were no more appreciable. CONCLUSION: DWI is very sensitive identifying the typical TGA lesions especially when a high b value (b > 1000s/mm2) is used combined to a thin section thickness (<5mm). Even if the diagnosis of TGA is primarily clinical, MRI can give a positive diagnostic support. The etiology and pathogenesis of this rare neurologic syndrome is still unclear: several factors, such as migraine-related mechanism, focal ischemia, venous flow abnormalities, and epileptic-like phenomena, have been suggested and/or hypothesized. Further studies are needed but it’s plausible that more advanced imaging techniques and will help to better understand the underlying mechanisms

Accuracy of SWI sequences compared to T2*-weighted gradient echo sequences in the detection of cerebral cavernous malformations in the familial form

The purpose of this study was to assess the accuracy of susceptibility-weighted imaging (SWI), compared with T2*-weighted gradient echo (GRE) imaging in assessing cerebral cavernous malformations

Imaging del tensore di diffusione nella SLA: esperienza preliminare nella valutazione della degenerazione dei FCS.

Comunicazione orale per il Congresso nazionale SIRM. Roma, 23-27 maggio 200

The value of serial MR imaging in the assessment of brain metastases volume control during stereotactic radiosurgery

Purpose: To evaluate early tumour control capabilities of Stereotactic Radiosurgery (SRS) in the treatment of brain metastasis and the role of follow-up MR imaging. Methods and Materials: MR imaging of 54 metastases in 31 patients treated with SRS who underwent follow-up MR imaging within 12 months were retrospectively reviewed. Tumours were characterized as either enlarged (>20% volume increase), stable (follow-up volume \ub120% of the initial volume), or decreased (> 0% volume decrease). Results: Within the first 6 weeks following SRS a decrease was observed in 25 (52%) of the tumours in the extent of 63% in size. Tumour reduction varied according to histopathological subtype with 38% of non-small cell lung carcinomas, 41% of breast carcinomas, 14% renal cell carcinoma and 8% of melanomas. At 9 weeks, 7 out of the 25 lesions had a transient tumour volume increase followed by tumour regression at 12 weeks. At 12 months 19 (37%) of lesions increased in volume in the extent of 41% in size. There was a significant higher tumour reduction in those carcinoma types that are considered as radiation sensitive. The best timing for follow-up imaging is at 6, 9 and 12 weeks to provide clinicians useful information. Conclusion: Stereotactic radiosurgery provide volume reduction in many brain metastases and it may be used alone or before whole brain radiation therapy to early tumour control. Follow-up MR imaging provide clinicians useful patient information aimed to make treatment decisions