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Shang-Yeong Kwan

Publications and source records attributed to Shang-Yeong Kwan.

11 recordsLinked to original sources
PubMed2007

Mixed alien hand syndrome coexisting with left-sided extinction secondary to a left corpus callosal lesion: a case report.

Alien hand syndrome (AHS) is actually two distinct syndromes with distinct clinical and anatomic features, that is, a frontal type and a callosal type. Frontal AHS occurs in the dominant hand; is associated with reflexive grasping, groping, and compulsive manipulation of tools. Callosal AHS is characterized primarily by intermanual conflict. We report a case of right frontal AHS and left callosal AHS (mixed AHS) secondary to ischemic stroke of the left corpus callosum (lesion extending from the genu to splenium) and right corpus callosum (minimal lesion in the splenium) in a 67-year-old male patient who also presented with left-sided tactile extinction. To our knowledge, rare reports have documented mixed AHS coexisting with nondominant side extinction secondary only to unilateral (left) callosal lesion, as in our case.

Aged↗
PubMed2006

A comparison of seizure outcome after callosotomy in patients with Lennox-Gastaut syndrome and a positive or negative history for West syndrome.

PURPOSE: This retrospective study was designed to clarify the role of West syndrome in post-callosotomy seizure outcome in patients with Lennox-Gastaut syndrome. METHODS: From September 1989 to May 1999, 74 patients diagnosed with Lennox-Gastaut syndrome received anterior corpus callosotomy at Taipei Veterans General Hospital, Taiwan. All patients were followed for more than 4 years after surgery. Among them, 21 (28.4%) patients had a history of West syndrome (Group A) whereas 53 (71.6%) patients did not have a history of West syndrome (Group B). Postoperative seizure outcome was compared for these two patient groups. RESULTS: A total of 16 (76.2%) patients in Group A (positive history) and 29 (54.7%) patients in group B (negative history) achieved significant improvement in seizures after surgery (e.g., seizure reduction of more than 50%). There was no statistical significance (p=0.088) in the difference in outcome between the two groups. CONCLUSIONS: A history of West syndrome does not appear to influence post-callosotomy seizure outcome in patients with Lennox-Gastaut syndrome.

Adolescent↗
PubMed2006

Corpus callosotomy in children.

INTRODUCTION: For children of medical resistant epilepsy without resectable epileptogenic zone, corpus callosotomy and vagus nerve stimulation (VNS) therapy are the two commonly used palliative epilepsy surgeries that can be considered. Although their routes and mechanisms to control epilepsy are different, both surgeries have shown their efficacy in selected candidates. The most common candidates for palliative surgery are in infants and children with organic encephalopathic types of epilepsy including infantile spasms/West syndrome, Lennox-Gastaut syndrome (LGS), severe epilepsy with multiple independent spike foci (SE-MISF) and selected symptomatic partial epilepsy to relief seizures and to stabilize co morbidities (Hirsch and Arzimanoglou, Revue Neurologique [Hirsch E and Arzimanoglou A, Rev Neurol (Paris). 160 Spec No 1:5S210-S219, (2004); Ohtahara S and Yamatogi Y, J Clin Neurophysiol 20(6):398-407, (2003); Wheless JW and Epilepsia 45(Suppl 5):17-22, (2004); Trevathan E, J Child Neurol 17 Suppl 2:2S9-2S22, (2002)]. DISCUSSION: Callosotomy is a major and destructive but affordable surgical procedure as compare to the relative simple but costly extracranial procedure of VNS therapy. However, callosotomy is a safe and effective palliative operation in neurosurgeons familiar with the surgical procedure. Equipments for callosotomy can be as simple as headlight and binocular loupes, self-retention brain retractor, bipolar cauterization, and simple microinstruments.

Adolescent↗
PubMed2006

Cerebral venous thrombosis initially presenting with acute subarachnoid hemorrhage.

We report the case of a 44-year-old man with superior sagittal and transverse sinus thrombi, who initially presented with venous subarachnoid hemorrhage over the right parietal sulci. After 7 days of intravenous anticoagulation therapy, his condition stabilized. Cerebral venous thrombosis can be difficult to diagnose and is further complicated when patients initially present with acute subarachnoid hemorrhage. A high index of clinical suspicion is needed to diagnose venous subarachnoid hemorrhage so that appropriate treatment can be initiated as promptly as possible.

Adult↗
PubMed2006

Isolated acute hearing loss as the presenting symptom of leptomeningeal carcinomatosis.

Leptomeningeal carcinomatosis is characterized by diffuse infiltration of the meninges by metastatic cancer. We report a rare case of leptomeningeal carcinomatosis with an initial presentation of isolated acute hearing loss. Progressive unsteady gait and multiple cranial nerve palsies ensued. Computed tomography of the chest with contrast revealed a 2 cm nodule over the right upper lung. Cytology of cerebrospinal fluid confirmed the diagnosis of adenocarcinoma. The patient was discharged after diagnosis. Isolated acute hearing loss is a rare initial presentation in leptomeningeal carcinomatosis, not necessarily with a known history of malignancy. A high index of suspicion is mandatory for accurate diagnosis.

Acute Disease↗
PubMed2006

Postictal aphasia with transient sulcal hyperintensity on MRI.

A 38-year-old man had postictal global aphasia after generalized tonic-clonic seizure, but recovered within 1 day. There was a focal increase in the signal intensity of the left frontoparietal sulci on fluid-attenuated inversion recovery magnetic resonance (MR) sequence 6 hours after the seizure, which disappeared 1 month later. The transient seizure-induced MR hyperintensity was possibly caused by ictal or postictal hyperemia and breakdown of the blood-brain barrier. This report aims to increase awareness of this condition and avoid unnecessary management.

Adult↗
PubMed2005

Prognostic value of electrocorticography findings during callosotomy in children with Lennox-Gastaut syndrome.

OBJECTIVE: To analyze findings and acute changes in electrocorticograms (ECoGs) obtained during corpus callosotomy in order to identify any relationships with the postoperative outcome of seizure activity. METHODS: We retrospectively analyzed ECoGs obtained during anterior callosotomy (4-6 cm) in 48 patients with Lennox-Gastaut syndrome (32 boys and 16 girls, age 1-20 years, mean age 7.6 years) who underwent surgery between July 1993 and November 1996 to correlate recording findings with postoperative seizure activity. At the time of analysis, all patients had been followed postoperatively for more than 4 years. RESULTS: Of 48 patients, 31 (64.6%) had significant improvement in seizure control after surgery. In pre-excisional ECoGs, 38 (79.2%) of 48 patients had bisynchronous epileptiform discharges. Patients (23 of 33 patients, 69.7%) with significant blockage of bisynchronous discharges recorded during callosotomy achieved the best postoperative seizure outcomes, but the difference did not reach statistical significance (P>0.05). CONCLUSIONS: Based on our experience, changes in ECoG during callosotomy do not predict postoperative seizure outcome. Insignificant blockage of bisynchronous epileptiform discharges in ECoGs during callosotomy does not predict a worse prognosis than that associated with significant intraoperative blockage.

Adolescent↗
PubMed2004

[Another seizure classification--Semiological Seizure Classification].

The International League Against Epilepsy (ILAE) introduced in 1981 a seizure classification based on clinical semiology, interictal EEG findings, and ictal EEG patterns. Such classification depends heavily on detailed electroclinical correlation. After 20 years' progress in epileptology, many clinicians have found it difficult to make a "definite" seizure diagnosis clinically without a series of electrophysiological examinations, particularly in the infants, and further advancement in epileptology has findings have made the previous classification inefficient. Lüders and colleagues have proposed a classification, Semiological Seizure Classification (SSC), based exclusively on ictal semiology, which was published in the official journal of ILAE-EPILEPSIA in 1998. The EEG, neuroimaging and other laboratory results should be analyzed separately and then integrated to define the epileptic syndromes. The seizure diagnosis is thus made through a "what-you-see-is-what-you-get" way. It has also provoked an extensive discussion about the necessity of this new classification. In this review, we present the original guideline, which has been used at The Cleveland Clinic Foundation for years, to introduce another method of epileptic seizure classification.

Adult↗
PubMed2003

Magnetoencephalographic analysis of bilaterally synchronous discharges in benign rolandic epilepsy of childhood.

The purpose of this study was to examine the spatial and temporal relationship between bilateral foci of bilaterally synchronous discharges in benign rolandic epilepsy of childhood (BREC) using a whole-scalp neuromagnetometer. We simultaneously recorded interictal magnetoencephalographic (MEG) and electroencephalographic (EEG) signals in six children with BREC. Interictal spikes were classified into three groups: bilaterally synchronous discharges (BSDs), unilateral discharges on right side (UD-R), and unilateral discharges on left side (UD-L). We used equivalent current dipole (ECD) modelling to analyse the cortical sources of interictal spikes. Both BSDs and UDs were found in Patients 1-4, whereas only UDs were identified in Patients 5 and 6. The ECDs of interictal spikes were located in rolandic regions, 10-20mm anterior and lateral to hand somatosensory cortices. Multi-dipole analysis of BSDs showed two ECDs in homotopic motor areas of the hemispheres. During BSDs, the right-sided activation preceded the left-sided activation by 15-21 milliseconds in Patients 1 and 2. In Patients 3 and 4, the activation occurred 17-20 milliseconds earlier in the left than the right hemisphere. Within the same hemisphere, the sources of BSDs and UDs were located in similar areas. In conclusion, our results imply the cortical epileptogenicity in bilateral perirolandic areas in BREC. The sequential activation during BSDs in both hemispheres suggest the existence of synaptic connections, possibly via the corpus callosum, between bilateral irritative foci.

Brain Mapping↗
PubMedDate not supplied

Lamotrigine adjunctive therapy in children with refractory epilepsy: a medical center study.

The aim of this study was to investigate the effects of adjunctive lamotrigine (LTG) in refractory epilepsy in Taiwan, especially including patients who had undergone ineffective epileptic surgeries. Totally, 27 recruited children and adolescents with refractory epilepsy were treated with LTG add-on therapy, but 23 were enrolled statistically during 2 years period trial. Ten of the 23 patients (43.5%), including 5 undergoing epileptic surgeries, before had a > 50% reduction in seizure frequency. Surprisingly, LTG was found to have excellent response in six patients with Lennox-Gastaut Syndrome (LGS), 5 of whom had received anterior 2/3 callosotomy prior to the trial. Non-seizure related positive effects were presented in 3 patients, including greater alertness and attentiveness in 2 patients and improvement in mood in one patient. This open trial found that LTG was an effective add-on anti-epileptic drug (AED) in Taiwanese children and adolescents with refractory epilepsy and in cases with LGS even after ineffective callosotomy.

Adolescent↗