O. Ekmekci

Visual evoked potentials in children with occipital epilepsies

The objectives of this study are to see if any visual evoked potential (VEP) differences are present in two forms of occipital epilepsy, childhood epilepsy with occipital paroxysms (CEOP) and symptomatic occipital epilepsy (SOE) with respect to etiology, as CEOP is a benign age- and localization-related idiopathic epilepsy while SOE is a symptomatic form. Nineteen patients with CEOP and 13 patients with SOE were included in the study and P100 potential latency and amplitude values obtained from these patients were compared with the values recorded from normal controls. The amplitude values recorded from the patients with CEOP were significantly high (P=0.033). P100 potential latency values recorded in patients with SOE were significantly long (P=0.028). High amplitude VEP responses were mostly attributed to hyperexcitability of the occipital cortical structures whereas prolonged latency P100 responses were attributed to occipital structural changes.

Proton MR spectroscopy in Rett syndrome

Seven patients (mean age 7.7yr) with Rett syndrome, a condition with progressive regression of psychomotor development are included in this study. Proton MR spectroscopy images were obtained with the multivoxel chemical-shift imaging mode (TR=1500ms, TE=40ms). Spectra from 224 voxels in the brain parenchyma were studied. N-acetyl aspartate (NAA), creatine (Cr), choline (Cho), and myoinositol (mI) peaks were quantitatively evaluated, and NAA/Cr, NAA/Cho, and Cho/Cr, mI/Cr ratios were calculated. Five age-matched normal cases were available as controls. In three patients with Rett syndrome spectroscopy findings were normal, and the metabolite ratios were similar to control cases. In the remaining four patients with the syndrome prominent decrease of the NAA peak was the main finding resulting in decreases in NAA/Cr (1.14+/-17), and NAA/Cho (1.08+/-27) ratios (p<0.0001). Cho/Cr ratios (0.93+/-26), and mI/Cr ratios (0.88+/-36) were normal compared to controls. There was no correlation between spectroscopic changes and clinical status of the patients. The findings suggested that not only reduced neuronal-dendritic arborizations but also decreased neuronal function could contribute to spectroscopy changes in Rett syndrome.

Atypical EEG findings in subacute sclerosing panencephalitis

OBJECTIVE To evaluate atypical electroencephalographic features in subacute sclerosing panencephalitis (SSPE) and to detect its relation to clinical features. METHODS Twenty-two patients aged 2-17 years (mean 9.4 years) with definite diagnosis of SSPE were studied. Their clinical data and EEG records were reviewed retrospectively. All EEG records were analysed for features of periodic complexes (PCs) in relation to age, age at onset, clinical stage and the rate of progression as well as duration of the disease. RESULTS Classical periodic complexes of SSPE were found in EEGs of 13 patients (group I). Atypical patterns were observed in EEGs of nine patients (group II). Two new atypical findings were identified: prolonged discharges which include sharp waves and slow waves for 4-7 s followed by suppression for 1-4s; and periodic complexes which consist of four or five sharp waves in every 2 s. We observed atypical EEG patterns were more frequently in Stage III, acute form, and the disease duration was longer than in the typical group. CONCLUSIONS Atypical EEG patterns in SSPE might be related to the progression of the disease, but this theory needs further longitudinal studies. SIGNIFICANCE We suggest atypical EEG patterns might be observed more frequently in patients with severe neurologic disability, more rapidly progressive disease and longer duration of disease.

Assessment of Early Cognitive Impairment in Patients with Clinically Isolated Syndromes and Multiple Sclerosis

Objective. The aim of our study was to investigate the frequency and pattern of cognitive impairment in patients with clinically isolated syndromes and definite diagnosis of multiple sclerosis within the last 2 years. Methods. We assessed the cognitive status of 46 patients aged 18–49 years with clinically isolated syndromes or definite diagnosis of multiple sclerosis who have onset of their symptoms within the last 2 years. Patients were matched with 40 healthy participants for age, sex, and educational level. Neuropsychological assessment was performed by stroop test, paced auditory serial addition test (PASAT), controlled oral word association test (COWAT), clock drawing test, trail making test (TMT), faces symbol test (FST). Hamilton Depression Scale and Modified Fatigue Impact Scale were used to quantify the severity of any depression and fatigue the subjects might suffer. Results. 19.6% of early MS/CIS group failed at 4 and more tests and had significant cognitive impairment focused on attention, executive functions, memory, and learning. No significant relationship was found between cognitive impairment and disability and fatigue scores. Discussion. Cognitive impairment can be present from the earliest stage of multiple sclerosis. It should be considered among the main manifestations of MS even in the earliest stages of the disease.

Myasthenia gravis and thymoma coexisting with myotonic dystrophy type 1

We describe a 34-year old man presenting with subacute generalized myasthenic symptoms. His clinical features and laboratory investigations demonstrated both myasthenia gravis and myotonic dystrophy type 1. The computerized tomography of chest revealed anterior mediastinal mass. The lymphocyte-rich thymoma was removed surgically and he received radiotherapy. Recent observations suggested that the patients with myotonic dystrophy may have an increased risk of benign and malignant tumours but its coexistence with thymoma is very rare. The risk of thymoma associated with myotonic dystrophy is unknown.

ADEM: diffusion MRI findings

Abstract Acute disseminated encephalomyelitis (ADEM) usually reveals patchy demyelinated lesions with high signal on T2-weighted sequences. Diffusion MRI in a 10-year-old patient with ADEM demonstrated two distinct lesion patterns occurring simultaneously in the cerebral white matter. These were a restricted diffusion pattern (high-signal on b =1000 mm 2 /s images with low apparent diffusion coefficient (ADC) values, and a demyelinating pattern (negative b =1000 mm 2 /s images with high ADC values). The patient responded well to intravenous methylprednisolone therapy. Further studies are required for detailed evaluation of such patterns in ADEM, and their clinical relevance, and for discrimination from other inflammatory encephalopathies.

A database for screening and registering late onset Pompe disease in Turkey

The aim of this study was to search for the frequency of late onset Pompe disease (LOPD) among patients who had a myopathy with unknown diagnosis registered in the pre-diagnostic part of a novel registry for LOPD within a collaborative study of neurologists working throughout Turkey. Included in the study were 350 patients older than 18 years who have a myopathic syndrome without a proven diagnosis by serum creatine kinase (CK) levels, electrodiagnostic studies, and/or muscle pathology, and/or genetic tests for myopathies other than LOPD. Acid alpha glucosidase (GAA) in dried blood spot was measured in each patient at two different university laboratories. LOPD was confirmed by mutation analysis in patients with decreased GAA levels from either both or one of the laboratories. Pre-diagnostic data, recorded by 45 investigators from 32 centers on 350 patients revealed low GAA levels in a total of 21 patients; from both laboratories in 6 and from either one of the laboratories in 15. Among them, genetic testing proved LOPD in 3 of 6 patients and 1 of 15 patients with decreased GAA levels from both or one of the laboratories respectively. Registry was transferred to Turkish Neurological Association after completion of the study for possible future use and development. Our collaborative study enabled collection of a considerable amount of data on the registry in a short time. GAA levels by dried blood spot even from two different laboratories in the same patient may not prove LOPD. LOPD seemed to be rarer in Turkey than in Europe.

Vestibular impairment in chronic inflammatory demyelinating polyneuropathy

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a common, treatable, autoimmune peripheral neuropathy considered to produce imbalance by weakness and proprioceptive impairment rather than vestibular impairment. We measured semicircular canal vestibular function in 21 CIDP patients (15M/6F) by the video head impulse test and postural stability with a battery comprising the modified Clinical Test of Sensory Integration and Balance, the Berg Balance Scale, the Dynamic Gait Index, the Fall Efficiency Scale, and the International Cooperative Ataxia Rating Scale. Of the 21 patients, 16 had vestibular impairment, ranging from mild—affecting just a single semicircular canal, to severe—affecting all 6 canals. Although the severity of the vestibular impairment did not correlate either with the severity of the postural imbalance or of the peripheral neuropathy, our data show that vestibular impairment is an additional challenge to balance that some CIDP patients will face.

Juvenile myasthenia gravis: Comparison of pre and postpubertal cases

Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor. GBM is characterized by cellular heterogeneity, rapid proliferation, angiogenesis and extensive invasion. Glioma tumor cells actively recruit to the tumor site microglia as well as peripheral macrophages, named Tumor Associate Macrophages (TAMs). TAMs have been shown to be deeply involved in tumor microenvironment by their ability to induce immunosuppression, angiogenesis and invasion. Macrophages that infiltrate cancer tissues can be classified inM1 (proinflammatory) and M2 (anti-inflammatory) according to their “activation” state. M1 macrophages produce type I proinflammatory cytokines, participate in antigen presentation and have an anti-tumorigenic role. Conversely, M2 macrophages produce type II cytokines, promote antiinflammatory responses and have pro-tumorigenic functions. Recent antitumor strategies are aiming to target TAMs with different approaches: inhibiting their recruitment, suppressing their survival, enhancing M1 like and blocking M2 activities. We focused our attention on M1 polarized macrophages and how they could influence glioma cells. We attempted to explore whether soluble factors secreted by M1 polarized microglia/macrophages could impact the cell fate of U251 glioma cells. Our preliminary experiments showed that M1 conditioned medium (M1CM) inhibits tumor cell proliferation aswell as promotes apoptosis. Extracellular vesicles have emerged as important mediators of intercellular communication in cancer. Among them, exosomes are defined as vesicles characterized by a size of 30–100 nm in diameter and microvesicles from 50 nm to 1000 nm, both recognized as important mediators of cell-to-cell communication. Currently studies in other type of cancers indicate that nanovesicles present in the CMplay a role in the modulation of tumor microenvironment. In line with these observations, we found that treatment of U251 cells with exosomes derived from M1 polarized microglia/macrophages decreases glioma cell proliferation. Interestingly, both M1 exosomes and microvesicles were more effective thanM1 total conditionedmedium.Wehypothesize that exosome re-polarization toward an M1 phenotype might oppose glioma progression. These findings shed new light on the complex communication networks in theGBMmicroenvironment and open new future therapeutic strategies.