David T. K. Chen

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Retinal cell development has been extensively investigated; however, the current knowledge of dynamic morphological and molecular changes is not yet complete. This study was aimed at revealing the dynamic morphological and molecular changes in retinal cell development during the embryonic stages using a new method of targeted retinal injection, in ovo(More)
The Structured Interview of Malingered Symptomatology (SIMS) is a self-report instrument that asks patients whether they experience atypical or implausible symptoms. The instrument has not been evaluated in an epilepsy population, and the potential for it to accurately distinguish between patients with psychogenic non-epileptic events (PNEE) and epileptic(More)
PURPOSE To evaluate whether certain preinduction clinical characteristics may influence the success rate of induction. METHODS We prospectively enrolled and attempted inductions on 51 patients who were suspected to have psychogenic nonepileptic events based on clinical grounds. In addition to careful examination of the reported ictal semiology, we(More)
Functional neuro-imaging techniques are helpful in the pre-surgical evaluation of epilepsy for localization of the epileptogenic zone as ancillary tools to electroencephalography (EEG) and magnetic resonance imaging (MRI) or when other localization techniques are normal, non-concordant or discordant. Positron emission tomography (PET) and ictal single(More)
We examined the usefulness of video versus EEG in isolation for the differentiation of epileptic seizures (ES) from psychogenic nonepileptic events (PNEE). Video-EEG recordings of 43 events in 43 patients (27 with ES and 16 with PNEE) were analyzed by experienced clinical epileptologists/electroencephalographers blinded to the patients' clinical histories.(More)
Use of novel drug delivery methods might enhance efficacy and reduce toxicity, in comparison with currently existing oral anti-epileptic drugs (AEDs). Novel methods aim to deliver optimal drug concentration more specifically to the seizure focus or foci. In this review, we first consider unconventional routes of drug delivery to the peripheral system, then(More)
BACKGROUND Vitamin A is involved in normal immune function and the maintenance of mucosal integrity through complex effects on cellular differentiation. OBJECTIVE We sought to determine whether serum vitamin A levels were associated with altered susceptibility to primary infection with HIV-1 in men with high-risk sexual behaviour and genital ulcers who(More)
OBJECTIVE To evaluate therapeutic efficacy upon augmenting the initial communication to patients regarding the diagnosis of psychogenic nonepileptic seizures (PNES) with a novel, brief group psychoeducation administered by the same team that provided the video-electroencephalography (VEEG) confirmed diagnosis and within 4 weeks of the diagnosis. METHODS(More)
Assessment of the effort level is an essential step in establishing the internal validity of any neuropsychological evaluation. The use of response bias measures as part of a core battery, however, is less common outside of forensic evaluations. The amount of time needed to administer many of these tests is often cited as a likely explanation for their(More)