Roula Hourani

Bone marrow mesenchymal stem cell transplantation in patients with multiple sclerosis: A pilot study☆

We explore the safety, and therapeutic benefit of intrathecal injection of ex-vivo expanded autologous bone marrow derived mesenchymal stem cells (BM-MSCs) in 10 patients with advanced multiple sclerosis (MS). Patients were assessed at 3, 6 and 12 months. Assessment at 3-6 months revealed Expanded Disability Scale Score (EDSS) improvement in 5/7, stabilization in 1/7, and worsening in 1/7 patients. MRI at 3 months revealed new or enlarging lesions in 5/7 and Gadolinium (Gd+) enhancing lesions in 3/7 patients. Vision and low contrast sensitivity testing at 3 months showed improvement in 5/6 and worsening in 1/6 patients. Early results show hints of clinical but not radiological efficacy and evidence of safety with no serious adverse events.

Asymptomatic brain magnetic resonance imaging abnormalities in splenectomized adults with thalassemia intermedia

Summary.  Background: A high incidence of thrombotic events in thalassemia intermedia (TI) patients led to the identification of a hypercoagulable state. Brain involvement has not been widely studied in TI, although limited reports confirm a low incidence of overt stroke and high incidence of silent brain infarcts. Patients/methods: This was a prospective study conducted on 30 adult, splenectomized TI patients. Patients were screened for absence of neurological signs or symptoms, and stroke‐related risk factors. Patient charts were reviewed for demographics, duration since splenectomy, and any history of transfusion therapy. Blood samples were obtained for complete blood counts and serum ferritin. Direct determination of liver iron concentration (LIC) was performed by R2 magnetic resonance imaging (MRI). Brain MRI was performed on all patients, looking for ischemic lesions and/or atrophy. Results: The mean age of patients was 32.1 ± 11 years (range, 18–54 years), with a male to female ratio of 13:17. Eighteen patients (60%) had evidence of one or more white matter lesions (WMLs) on brain MRI, all involving the subcortical white matter. Fourteen patients had evidence of multiple WMLs, with a mean of 5 ± 10 lesions (range, 2 to > 40 lesions). The vast majority of patients (94%) had small (< 0.5 cm) to medium (0.5–1.5 cm) WMLs, with only one patient showing evidence of a large (> 1.5 cm) WML. Eleven patients (37%) had mild cerebral atrophy. On multivariate analysis only age and transfusion history were independently and significantly associated with the occurrence of zero, single or multiple WMLs. Conclusion: WMLs and brain atrophy are a common finding in adult, splenectomized, TI patients. Increasing age and transfusion naivety are associated with a higher incidence and multiplicity of lesions.

L-Asparaginase-induced Posterior Reversible Encephalopathy Syndrome during Acute Lymphoblastic Leukemia Treatment in Children

L-asparaginase is a critical component in the treatment of acute lymphoblastic leukemia in children. It is known to cause coagulation abnormalities, thrombosis and hemorrhage in the central nervous system in addition to vasculitis and hypersensitivity reactions. The purpose of this article is to present the first case-series of posterior reversible encephalopathy syndrome (PRES) associated with L-asparaginase treatment. We report 3 cases of children with acute lymphoblastic leukemia who developed seizures and altered sensorium after L-asparaginase therapy. MRI showed increased T(2) signal intensity predominant in the posterior regions of the brain suggestive of PRES. Two of our patients developed septic shock and deteriorated whereas one patient improved and recovered completely.

Brain magnetic resonance angiography in splenectomized adults with β-thalassemia intermedia.

Background: Hypercoagulability and venous thromboembolism are common in patients with β‐thalassemia intermedia (TI), especially in the splenectomized adult. Although arterial involvement is not commonly reported, we have recently observed a high prevalence (60%) of silent brain infarction on brain MRI in 30 splenectomized adults with TI. The pathophysiology of these white matter lesions remains unknown. Methods: In this prospective work, we evaluated magnetic resonance angiography (MRA) scans of the same cohort of 30 patients. Data collected were the presence or absence of vascular lesions, their locations, and severity. Correlations between MRA abnormality and patients/disease characteristics were evaluated. Comparisons between MRA and previous MRI findings were made. Results: Of 29 evaluable patients, 8 (27.6%) had evidence of arterial stenosis on MRA. The majority of lesions had mild narrowing and mostly involved the internal carotid artery. Five patients (17.2%) had evidence of aneurysms. Low total hemoglobin and high non‐transferrin‐bound iron levels independently characterized patients with evidence of stenosis on MRA. Among the 18 patients with silent brain infarction on MRI, three had evidence of stenosis on MRA with only one patient having lesions that could explain the silent infarcts. Conclusions: Cerebral vasculopathy is common in splenectomized adults with TI. However, large‐vessel disease does not explain the occurrence of silent brain infarction. The combined use of MRA and MRI better identifies splenectomized TI adults with neuroimaging abnormalities.

MR imaging findings in autosomal recessive hereditary spastic paraplegia.

BACKGROUND AND PURPOSE: Hereditary spastic paraplegia (HSP) is a disorder characterized by degeneration of the corticospinal tracts and posterior column of the spinal cord. Previously described radiologic findings included nonspecific brain abnormalities such as brain atrophy and white matter lesions, as well as atrophy of the spinal cord. In our study, we aimed to better characterize brain and spine MR imaging findings in a series of patients with HSP. MATERIALS AND METHODS: Nine patients from 4 different Lebanese families with the autosomal recessive form of HSP were included in the study. All patients underwent brain and whole-spine MR imaging. We assessed the presence of white matter abnormalities mainly along the corticospinal tracts, brain atrophy, thinning of the corpus callosum, and the presence of spinal cord atrophy or abnormal signal intensity. RESULTS: Imaging revealed mild brain atrophy (44%), atrophy of the corpus callosum (55%), white matter lesions (67%), abnormal T2 high signal intensity in the posterior limb of the internal capsule (55%), and mild spinal cord atrophy (33%). CONCLUSIONS: The MR imaging findings of HSP are nonspecific and variable; however, the most prominent features include atrophy of the corpus callosum, T2 signal intensity in the posterior limb of the internal capsule, and spinal cord atrophy.

PERIOSTEAL OSTEOBLASTOMA OF THE CALVARIA MIMICKING A MENINGIOMA

While osteoblastoma of the cranial vault is rare, the periosteal form of the tumor is highly unusual, with only one case reported in the English literature. We report on a 24-year-old woman presenting with headache and tinnitus. Magnetic resonance imaging of the brain showed an extra-axial temporal mass with findings that were suggestive of a meningioma. The mass was excised completely, and histological examination revealed a periosteal osteoblastoma arising from the inner surface of the temporal bone and adhering to the dura. The tumor was strongly positive for epithelial membrane antigen, a feature not previously described in osteoblastoma, and one that could lead to a mistaken diagnosis of metaplastic meningioma in a limited sample. A detailed literature review of 40 other reported cases of calvarial osteoblastoma is presented. Apart from being slightly more common in females, calvarial osteoblastoma is similar in all other respects to that arising at conventional skeletal sites. Accurate histological diagnosis of a calvarial osteoblastoma requires adequate sampling of the tumor, including its interface with adjacent structures. Correlation with the radiological findings is crucial for the diagnosis in most cases; however, it is not helpful in differentiating the rare intracranial periosteal variant from a meningioma.

Schwannoma of the Tentorium Cerebelli in a Child

Intracranial schwannomas not arising from a cranial nerve are very rare. Schwannomas of the dura are even rarer; in the literature, we found only two cases: a schwannoma of the falx and one of the torcula. We report a third case of a 9-year-old girl with a schwannoma of the tentorium cerebelli. The different theories concerning the origin of this tumor in this particular location are discussed.

Bilateral superior semicircular canal dehiscence in a child with sensorineural hearing loss and without vestibular symptoms

To report a rare case of bilateral superior semicircular canal dehiscence (SCCD) in a child. Case report, 11-year-old female patient. Descriptive case report. Audiological findings of bilateral symmetrical low frequency sensorineural hearing loss with ascending curves and bilateral superior semicircular canal dehiscence on a high resolution computed tomography (CAT) scan. The young child presented with bilateral fluctuating hearing loss with no vestibular symptoms. She was found to have bilateral superior semicircular canal dehiscence. We hereby present a rare case of bilateral semicircular canal dehiscence found incidentally on high resolution CAT scan in a young child during work up for bilateral sensorineural hearing loss.

Fibroblastic and myofibroblastic tumors of the head and neck: Comprehensive imaging-based review with pathologic correlation

Fibroblastic and myofibroblastic tumors of the head and neck are a heterogeneous group of disorders characterized by the proliferation of fibroblasts, myofibroblasts, or both. These tumors may be further subclassified on the basis of their behavior as benign, intermediate with malignant potential, or malignant. There are different types of fibroblastic and myofibroblastic tumors that can involve the head and neck including desmoid-type fibromatosis, solitary fibrous tumor, myofibroma/myofibromatosis, nodular fasciitis, nasopharyngeal angiofibroma, fibrosarcoma, dermatofibrosarcoma protuberans, fibromatosis coli, inflammatory myofibroblastic tumor, ossifying fibroma, fibrous histiocytoma, nodular fasciitis, fibromyxoma, hyaline fibromatosis and fibrous hamartoma. Although the imaging characteristics of fibroblastic and myofibroblastic tumors of the head and neck are nonspecific, imaging plays a pivotal role in the noninvasive diagnosis and characterization of these tumors, providing information about the constitution of tumors, their extension and invasion of adjacent structures. Correlation with the clinical history may help limit the differential diagnosis and radiologists should be familiar with the imaging appearance of these tumors to reach an accurate diagnosis.

Solitary fibrous tumor of the scalp in a child.

Solitary fibrous tumors (SFTs) are rare mesenchymal neoplasms that arise most commonly in the pleura but have been increasingly reported in extrapleural sites. The authors report the case of an SFT of the scalp that manifested as an enlarging scalp mass in a 2-year-old boy. The mass was surgically excised. Histological examination showed it to be composed of fusiform cells of variable cellularity with a central hyalinization zone. Immunohistochemical staining was positive for CD34 and negative for smooth muscle actin, S100 protein, desmin, and h-caldesmon. On 1-year follow-up, there was no recurrence of the mass. This case presented some diagnostic difficulty because of the wide range of possible diagnoses for a pediatric scalp mass; however, the distinct immunohistochemical profile helped to eliminate other more frequent fibrous tumors of the scalp. The behavior of scalp SFTs is usually benign, but their course can be unpredictable, and recognition of these lesions is essential.