Major white matter fiber changes in medically intractable neocortical epilepsy in children: a diffusion tensor imaging study.

This study aimed to investigate the extent of microstructural changes in the major white matter fibers and to evaluate whether diffusion tensor imaging (DTI) adds any lateralizing information in children with medically intractable neocortical epilepsy secondary to focal cortical dysplasia. Patient group included twenty-three consecutively enrolled patients with medically intractable focal neocortical epilepsy and focal cortical dysplasia histopathologically confirmed. Thirteen patients (56.5%) had no visible lesion on the conventional magnetic resonance imaging (MRI). Fractional anisotropy (FA) was measured for regions of interest (ROIs) in each major white matter fiber. FA in patients was compared with eighteen age-matched healthy controls. Patient group had lower FA values at corpus callosum, bilateral inferior frontooccipital fasciculus (IFO), bilateral inferior longitudinal fasciculus (ILF) and left superior longitudinal fasciculus (SLF) compared to controls (p<0.05). In the left-side surgery group, the left SLF FA value was lower than controls, while in the right-side surgery group, the right SLF FA values were lower than controls (p<0.05). In the patient group as a whole, ipsilateral SLF FA was significantly lower than the contralateral SLF (p<0.05). Widespread decrease in FA values in the patients compared with the controls suggests that the pathologic changes extend diffusely to most major white matter tracts. In the patient group, the ipsilateral SLF to the seizure focus had greater change compared to the contralateral SLF. These data suggest that the detection of DTI abnormality has an added value to lateralization.

Early progressive encephalopathy in boys and MECP2 mutations.

MECP2 mutations mainly occur in females with Rett syndrome. Mutations have been described in 11 boys with progressive encephalopathy: seven of nine with affected sisters and two de novo. The authors report four de novo occurrences: three pathogenic and one potentially pathogenic. Common features include failure to thrive, respiratory insufficiency, microcephaly, and abnormal motor control. MECP2 mutations should be assessed in boys with progressive encephalopathy and one or more of respiratory insufficiency, abnormal movements or tone, and intractable seizures.

Viral etiologies of encephalitis in Thai children.

A prospective study of childhood encephalitis was performed in Bangkok from 1996 through 1998. The viral agents identifiable in 26 (65%) of 40 children were dengue virus (8), Japanese encephalitis (6), herpes simplex virus (4), human herpes virus type 6 (3), mumps (2), enterovirus (1), varicella-zoster virus (VZV) (1) and rabies (1).

Ketogenic diet: an alternative treatment for refractory epilepsy in children.

RATIONALE: The aim of this study was to establish the first ketogenic diet treatment program for refractory epilepsy in Thailand and to assess its feasibility as well as its efficacy. METHOD: Children with refractory epilepsy were enrolled in the study. This was a prospective open trial study with 35 children (16 boys and 19 girls). Not all patients started on the diet at the same time. Each patient was cumulatively enrolled in this study over the period of 4 years. The mean age on diet was 5.37 +/- 3.57 years (2 months-13 years), mean age of onset of seizures was 19.2 +/- 27.47 months (1 days-8 years), and an average duration on ketogenic diet was 7.67 months (6 days to 29 months). The classic "4:1" formula ketogenic diet was used with some modification. The patient's parents were allowed to improvise and use any fatty diets available in the market such as coconut milk if needed. Parents were closely supervised and instructed on how to prepare the patient's own meals while in the hospital and continued to attend neurology and nutrition clinics. The seizure outcome and side effects were monitored as well as a daily test for urine ketone. RESULTS: At 1 month, 3 months, 6 months, and 12 months duration on the diet, 90 per cent seizure reductions were achieved in 62.5 per cent, 68.18 per cent, 75 per cent, and 66.67 per cent of patients remaining on the diet, respectively. The number of antiepileptic drugs (AEDs) used by each patient also decreased as a result of better seizure control. CONCLUSION: Ketogenic diet can be tried as a management option for refractory epilepsy. It is not difficult to implement even in a developing country like Thailand where resources are limited. It may also help reduce the cost of treatment especially in view of the high prices of the new AEDs.

Dengue infection presenting with central nervous system manifestation.

The objective of this study was to investigate the possibility of dengue virus infection causing an abnormal neurologic presentation. Between 1996 and 1998, all pediatric patients with clinical manifestations of encephalitis-like illness who were admitted to the Department of Pediatrics, Siriraj Hospital were prospectively studied for any evidence of dengue virus infection. The diagnosis of dengue virus infection was based on mosquito viral isolation and serologic and polymerase chain reaction (PCR) evidence. Of 44 patients with the preliminary diagnosis of acute viral encephalitis, 8 were diagnosed with dengue infection. All of these 8 patients were diagnosed by serology. In addition to the serologic diagnosis, four also had positive PCR, one had positive viral isolation, and one had both positive PCR and viral isolation. Only two patients were diagnosed by serologic evidence alone. All except one had clinical courses and laboratory findings compatible with typical dengue infection. All had obvious encephalitic clinical manifestations with normal cerebrospinal fluid findings except one patient, who had mildly increased cerebrospinal fluid protein. All of these patients recovered completely and had benign clinical courses except one patient, who developed leakage symptoms. None had liver failure. Dengue virus can cause acute encephalopathy with fever. It can masquerade as other types of acute viral encephalitis. However, its clinical course and prognosis are usually favorable.

Lateralizing value of asymmetric tonic limb posturing observed in secondarily generalized tonic-clonic seizures.

PURPOSE: A striking asymmetry of limb posture occurs during secondarily generalized tonic-clonic (GTC) seizures wherein one elbow is extended while the other is flexed during the tonic phase of the GTC seizure. We have named this phenomenon asymmetric tonic limb posturing (ATLP) or the "Figure 4 Sign." METHODS: Fifty-nine secondarily GTC seizures from 31 patients with partial epilepsy who underwent successful epilepsy surgery were analyzed, in addition to another group of 64 GTC and generalized clonic seizures from 26 patients collected prospectively over a 7-month period. Three observers reviewed these seizures blinded to the side of ictal EEG onset and other clinical data. RESULTS: The extended elbow was contralateral to the side of ictal onset in 35 of 39 patients who had ATLP during their seizures. The kappa index, a measure of interobserver agreement, was calculated, and ATLP was found to have very good agreement between observers. CONCLUSIONS: In secondarily generalized tonic-clonic seizures, ATLP (Figure 4 Sign) may sometimes be only available lateralizing sign.

Epilepsy awareness among school teachers in Thailand.

PURPOSE: Epilepsy is one of the most common neurologic disorders of childhood. However, in Thailand, as well as in most of other developing countries, little attention has been paid to improve the public knowledge regarding epilepsy. Currently public attitude toward epilepsy is rather negative, full of prejudices and bias. Children with epilepsy in Thailand still find themselves confronted with social barriers that prevent them from academic achievements, in addition to the limitation that the disease itself has already placed on them. To delineate the magnitude and scope of this problem, we performed a small pilot study to assess the knowledge, attitude, and practice of epilepsy in the school teachers in Thailand whose major impact on the children is manifested by attitudes and learning. METHODS: The study was conducted by sending simple self-administered questionnaires to 360 schools all over Thailand. The questionnaires contained 14 questions relating to epilepsy awareness, attitudes, and first-aid management of seizures. RESULTS: We found that 38% of respondents had not heard of or read about epilepsy, and 46.6% believed that epilepsy is a chronic incurable disease. Fifteen percent of the respondents preferred to place all children with epilepsy in a special classroom. Furthermore, half of the respondents who had experience with first-aid management of seizures used improper and potentially harmful measures. CONCLUSIONS: Besides the proper management of epilepsy, a general public education campaign for epilepsy and the need to address and correct the existing biases are necessary to improve the quality of life of children with epilepsy in Thailand.

Salivary antiepileptic drug levels in Thai children.

A total of 123 patients were enrolled in this study. 88 patients were enrolled in the first stage of the study, which was to evaluate the commercial salivary collecting devices: Orasure and Omnisol. 35 patients were enrolled in the second stage of the study and were asked to spit whole saliva samples for further analysis of AED levels. Serum AED levels and corresponding saliva AED levels were paired and analyzed for the correlation coefficients with the linear regression model. None of the commercial salivary collecting devices can provide the linear regression correlation between the serum AED level and saliva AED level in all three AEDs studied. The correlation coefficients of serum and whole saliva AED levels of phenobarbital, phenytoin, and carbamazepine were highly correlated (r-squared were 0.981, 0.976, and 0.888, respectively). Saliva samples can be used clinically to monitor the AEDs level in phenobarbital, phenytoin and carbamazepine. This would be another alternative method of therapeutic drug monitoring that can be done painlessly and is easier in children than the blood sampling method.

Lateralizing value and semiology of ictal limb posturing and version in temporal lobe and extratemporal epilepsy.

PURPOSE: Unilateral dystonic limb posturing in partial seizures has been shown to be an accurate lateralizing sign indicating seizure onset in the contralateral hemisphere. However, its clinical utility may be reduced by confusion with other lateralized ictal motor phenomena. In this study, the ictal phenomena of dystonic limb posturing, tonic limb posturing, unilateral immobile limb, and version were distinguished and examined in patients with temporal and extratemporal seizures. METHODS: Partial seizures in 54 patients, successfully treated by surgery (34 temporal, 20 extratemporal; 14 frontal, 3 parietal, and 3 occipital), were analyzed blindly by 3 reviewers. Interobserver agreement was tested with kappa indexes and positive predictive value (PPV) was determined for each sign. RESULTS: In patients with temporal lobe epilepsy (TLE), dystonic posturing occurred in 35.3% (kappa 0.78, positive predictive value (PPV) for the sign being contralateral to seizure onset 92%); tonic limb posturing occurred in 17.7% (kappa 0.36, PPV 40%); unilateral immobile limb occurred in 11.8% (kappa 0.23, PPV 100%); and version occurred in 35.3% (kappa 0.77, PPV 100%). In patients with extratemporal epilepsy, dystonic posturing occurred in 20.0% (kappa 0.31, PPV 100%); tonic limb posturing occurred in 15.0% (kappa 0.08, PPV 67%); and version occurred in 40.0% (kappa 0.54, PPV 100%). The higher kappa indexes were significant for dystonic posturing (p < 0.001) and tonic limb posturing (p = 0.032) in TLE. Dystonic posturing (p = 0.034), tonic posturing (p = 0.07), and version (p = 0.0038) occurred earlier in extratemporal seizures than in temporal seizures. CONCLUSIONS: Of the limb ictal motor phenomena, only dystonic posturing was accurate and had good interobserver agreement.

Möbius syndrome in infant exposed to cocaine in utero.

The pathophysiology of Möbius syndrome has been debated for decades. A vascular etiology is currently favored because it explains the wide clinical spectrum of this syndrome. An infant is reported who was born with Möbius syndrome after a pregnancy complicated by heavy maternal use of cocaine and alcohol. We speculate that cocaine-induced vasoconstriction at a critical time of cerebrovascular development produced a vascular disruption sequence leading to the Möbius syndrome.