Assessment of the Relationship between Vigabatrin and Visual Field Defect in Children

PURPOSE: The authors carried out this study to determine the relationship between vigabatrin (VGB) and visual field defect. METHODS: Seventy eight patients older than 8 years who had epilepsy which had developed and been diagnosed, and were receiving add-on therapy, were the subjects of this study. If suspicious results were obtained from the initial test with the Humphrey automatic perimeter, the patient was tested again with the Goldman perimeter. Follow-up examinations were performed on these patients after 6 months. RESULTS: In this study, five of the 78 patients had suspicious primary test results, but upon the second examination they were all found to be normal. Thus there were no patients with visual field defects. CONCLUSIONS: VGB is a drug which may cause visual field defects, but in this study no patients presented with this symptom. Instead of limiting the use of VGB due to the adverse effect of visual field defect in the initial treatment of partial seizure and infantile spasm untreatable with other medication, if used with care it may not cause serious problems. Screening for visual defect is recommended, and in patients taking VGB regular examination is necessary.

A Follow-Up Study after Discontinuation of Antiepileptic Drug Therapy in Children with Well-Controlled Epilepsy: The Factors that Influence Recurrence

PURPOSE: There has been no exact answer to the question of when to discontinue antiepileptic drugs(AEDs) in children with well-controlled epilepsy for a long period. This study is about the risk factors of relapse after withdrawal of AEDs in seizure(Sz)-free patients to show a guideline for discontinuation of AEDs. METHODS: One hundred and sixty-nine children were diagnosed as epileptic at the Pediatric Dept.of Kyung-Hee Univ. between 1993 to 1998, in whom AEDs had been withdrawn after at least two years of Sz-free period. Univariate analysis using Kaplan-Meier survival analysis and multivariate analysis using Cox-proportional hazard model were performed for sixteen risk factors. RESULTS: Forty-nine of the 169 patients(28.9%) had recurrence of Szs. The mean follow-up after withdrawal of AEDs was 4.1 years, mean treatment period was 4.1 years, and the mean Sz-free period was 3.3 years. Factors associated with an increased risk of relapse were young age at onset, symptomatic Sz, Sz type in West and Lennox-Gastaut syndrome, neurologic deficit, longer Sz-controlling period, shorter total treatment period, number of AEDs used(more than one drug), age at withdrawal of AEDs, and Sz-free period less than two years in univariate analysis using Kaplan-Meier mothod. From multivariate analysis, the factors indicating a significantly higher relapse risk were pre-treatment period after first Sz attack, Sz-controlling period, Sz-free period, number of AEDs used, neurologic abnormalities. CONCLUSIONS: For epileptic children who were Sz-free for more than two years, and were more than six-years-old, the discontinuation of AEDs should be considered positively, according to age of onset, Sz type, age at withdrawal of AEDs, total treatment period, Sz-controlling period, number of AEDs used, etiology, neurologic deficit, and the wishes of the patients and the their parents.

Usefulness of Brain Tc-99m HMPAO SPECT in Establishing Lateralization of Intractable Seizure in Children

PURPOSE: To determine the role of Tc-99m HMPAO SPECT imaging in children with intractable seizure by evaluating the interictal period. METHODS: We compared the EEG, CT and MRI medical records with those of Tc-99m HMPAO SPECT in 42 patients with intractable seizure referred to Kyunghee University Hospital, from April 1983 to September 1998, retrospectively. RESULTS: Mean age was 8.3 years and male to female ratio was 2.5 : 1. Multiple surface EEG recordings were performed in 42 patients and EEG findings of all patients showed an epileptogenic focus, with the most common area of abnormal findings being the Lt. sides. Brain CT was performed in 23 out of 42 patients(54.8%), and 15 out of the 23 patients(65.2%) showed abnormal findings and the most common area of abnormal findings were both sides. Brain MRI was performed in 21 out of 42 patients(50.0%), and 14 of the 21 patients(66.6%) showed abnormalities and the most common area of abnormal findings were both sides. In 32 out of the 42 patients (76.2%), SPECT images showed abnormal cerebral perfusion, most common area of hypoperfusion were Lt. sides. In 10 out of 14 cases, there were lateralizing abnormalities on the same side shown in SPECT and EEG, CT or MRI findings. CONCLUSION: We concluded that Tc-99m HMPAO SPECT seemed to be a useful tool in the evaluation of intractable seizure patients.

Usefulness of Brain Tc-99m HMPAO SPECT in Establishing Lateralization of Intractable Seizure in Children

PURPOSE: To determine the role of Tc-99m HMPAO SPECT imaging in children with intractable seizure by evaluating the interictal period. METHODS: We compared the EEG, CT and MRI medical records with those of Tc-99m HMPAO SPECT in 42 patients with intractable seizure referred to Kyunghee University Hospital, from April 1983 to September 1998, retrospectively. RESULTS: Mean age was 8.3 years and male to female ratio was 2.5 : 1. Multiple surface EEG recordings were performed in 42 patients and EEG findings of all patients showed an epileptogenic focus, with the most common area of abnormal findings being the Lt. sides. Brain CT was performed in 23 out of 42 patients(54.8%), and 15 out of the 23 patients(65.2%) showed abnormal findings and the most common area of abnormal findings were both sides. Brain MRI was performed in 21 out of 42 patients(50.0%), and 14 of the 21 patients(66.6%) showed abnormalities and the most common area of abnormal findings were both sides. In 32 out of the 42 patients (76.2%), SPECT images showed abnormal cerebral perfusion, most common area of hypoperfusion were Lt. sides. In 10 out of 14 cases, there were lateralizing abnormalities on the same side shown in SPECT and EEG, CT or MRI findings. CONCLUSION: We concluded that Tc-99m HMPAO SPECT seemed to be a useful tool in the evaluation of intractable seizure patients.