Chun-Hing Yiu

Taipei Veterans General Hospital, T’ai-pei, Taipei, Taiwan

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Publications (21)44.02 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: To better clarify abdominal auras and their clinical correlates, we enrolled 331 temporal lobe epilepsy patients who received surgical treatment. Detailed descriptions of their auras were obtained before surgery and reconfirmed during postoperative outpatient follow-ups. Pathology revealed mesial temporal sclerosis (MTS) in 256 patients (77.3%) and 75 non-MTS. Of 214 MTS patients with auras, 78 (36.4%) reported abdominal auras (vs. 30.4% in non-MTS, p=0.439): 42 with left-sided seizure onset, and 36 with right-sided seizure onset. Moreover, 49 of the 78 MTS patients had abdominal auras accompanied by rising sensations (vs. 2 of 14 in non-MTS group, p=0.004). The "rising air" was initially described to locate to the epigastric (47.8%) or periumbilical area (45.7%) and mostly reached the chest (40.4%) or remained in the abdominal region (27.1%). An epigastric location of "rising air" favored a left-sided seizure onset, and non-epigastric areas favored right-sided seizure onset (p=0.018). Finally, we found that abdominal auras with or without rising sensations did not predict postoperative seizure outcomes.
    Epilepsy & Behavior 10/2012; 25(3):386-390. · 1.84 Impact Factor
  • Clinical neurology and neurosurgery 03/2012; 114(9):1283-6. · 1.30 Impact Factor
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    ABSTRACT: The duration of sustained seizures (SS) plays a crucial role in the occurrence of spontaneous recurrent seizures (SRS) in experimental animals. We tested whether rats with varying durations of initial convulsive SS exhibited differential neurogenesis patterns in the hippocampal dentate gyrus that may be related to subsequent epileptogenesis. Sprague-Dawley rats with pilocarpine-induced convulsive SS were divided into short SS (30 min) and long SS (2 h) groups. Their behavior was monitored to identify convulsive SRS. From 1 to 28 days post-SS, cell proliferation was evaluated by 5'-bromo-2'-deoxyuridine (BrdU) labeling and immature neuroblasts in the dentate gyrus were identified by doublecortin immunohistochemistry. Convulsive SRS was detected in 8 out of the 9 long SS rats, but not in the 9 short SS rats. During day 1-3, proliferative cells were diffusely localized throughout the hippocampus in the long SS rats but were primarily confined within the subgranular zone in the short SS rats. Within the subgranular zone, a significant increase in the number of BrdU-positive cells was found at days 3 and 7 after the long SS and on day 1 after the short SS. Notably, abnormal dendritic outgrowth and hilar-ectopic localization of doublecortin-positive cells were present in the long SS rats. In conclusion, aberrant hippocampal neurogenesis following long SS may contribute to the development of SRS.
    Epilepsy research 02/2012; 98(2-3):206-15. · 2.48 Impact Factor
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    ABSTRACT: The characteristic electroclinical features of Lennox-Gastaut syndrome (LGS) have been extensively reported, but the influence of the constellation of slow spike-and-wave (SSW) complexes with multiple seizure types (including atypical absence seizures [AAS] and tonic seizures [TS]) on patients with this syndrome is still unclear. We report the case of a 28-year-old woman who developed AAS and brief asymmetric TS at the age of 14 years. Her seizure disorder met diagnostic criteria for LGS (SSW on electroencephalogram and multiple seizure types), but there was no intellectual impairment and an interictal alpha EEG. Even 14 years after the onset of her epilepsy, she maintained fairly normal cognitive function, although she was bothered by frequent brief and subtle episodes of AAS and TS.
    Seizure 08/2011; 20(10):820-3. · 2.00 Impact Factor
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    ABSTRACT: Reflex epilepsy is characterized by seizures that are precipitated by a specific identifiable factor. We describe here the case of a 21-year-old man with notable absence epilepsy since the age of 11 who experienced generalized convulsions 2 years after onset (in the absence of antiepileptic therapy) and reflex absence seizures triggered by walking 7-10 steps. To our knowledge, this case report is the first describing reflex absence epilepsy seizures induced by gait.
    Epilepsy & Behavior 08/2011; 22(2):395-7. · 1.84 Impact Factor
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    ABSTRACT: To understand the treatment-seeking behavior of people with epilepsy (PWE), 403 PWE were surveyed using structured face-to-face interviews. Nearly half (49.1%) of them had previously tried complementary and alternative medicine (CAM); traditional Chinese medicine (51.5%) and temple worship (48.0%) were the most frequently used forms of CAM. In the 155 patients with adult-onset epilepsy, seeking CAM was substantially more common among females (OR=2.11, 95% CI=1.05-4.24, P=0.036), patients with frequent seizures (OR=2.68, 95% CI=1.30-5.53, P=0.008), patients with less educated parents (OR=2.16, 95% CI=1.06-4.41, P=0.034), and patients with religious beliefs (OR=2.84, 95% CI=1.23-6.56, P=0.015). In the 248 patients with childhood-onset epilepsy, frequent seizures (OR=2.23, 95% CI=1.32-3.77, P=0.003) and lower level of parental education (OR=2.71, 95% CI=1.45-5.06, P=0.002) were significantly associated with CAM use. The patients who seek CAM before receiving conventional medical treatment decreased after implementation of the National Health Insurance (NHI) (34/188 before NHI vs 22/215 after NHI, P=0.023). This study showed that the prevalence of CAM use by PWE in Taiwan is high and that a convenient NHI program can affect treatment-seeking behavior.
    Epilepsy & Behavior 08/2011; 22(2):308-12. · 1.84 Impact Factor
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    ABSTRACT: We report a 19-year-old man who presented to our facility with medically intractable, symptomatic generalized epilepsy manifesting as generalized tonic-clonic seizures (GTCs). Before he underwent an anterior callosotomy (6 cm), these seizures, which he had experienced for 11 years, seemed to have a left-sided focal origin. Intraoperatively, no epileptiform discharges were found on the electrocorticogram (ECoG) performed prior to sectioning, but more than 10 left-sided seizures were recorded after sectioning. In the 10 years since surgery, the patient's seizures have remained generalized; however, the frequency and severity of the seizures have decreased. These findings indicate that the presence of electrocorticographic seizures, as measured by ECoG immediately following callosotomy, may not predict a poor surgical outcome, even though such a finding might be indicative of epileptogenicity in general.
    Journal of Clinical Neuroscience 10/2009; 17(1):132-4. · 1.25 Impact Factor
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    ABSTRACT: To evaluate the efficacy and safety of gamma knife radiosurgery (GKS) in treating temporal lobe epilepsy, GKS was performed in four adult patients with recurrent complex partial seizures who underwent incomplete anterior temporal lobectomy (ATL) but were reluctant to undergo a second resective surgery. A marginal dose of 24.5-25Gy, corresponding to 65-70% isodose curve, was delivered to the treatment target that included the residual amygdala and the head and anterior body of the hippocampus. None of the patients had severe acute side effects but three patients had radiation-induced MRI signal changes around the target volume 13, 20, and 24 months after GKS, respectively. All four patients had significant seizure reduction during the first 6-month period and clinical efficacy persisted throughout the 2-year follow-up period. All of the patients also had improved neuropsychological profiles, including memory function and quality-of-life, compared to their pre-GKS conditions. In conclusion, the safety and clinical efficacy of GKS make it a reasonable and suitable therapeutic alternative for patients with recurrent seizures after incomplete ATL. A higher marginal dose of >25Gy and wider coverage may be more clinically beneficial but warrant further investigation.
    Seizure 06/2009; 18(7):511-4. · 2.00 Impact Factor
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    ABSTRACT: We report the case of a girl with hemimegalencephaly (HME) and Lennox-Gastaut syndrome (LGS) treated by callosotomy at 1 year of age. Over 10 years, her seizure frequency and severity decreased markedly. Hemispherectomy is the main surgical option for HME although HME appears to correlate with a less favorable seizure outcome. However, the clinical presentation of LGS and possible generalized cortical dysplasia, which is indicative of a secondarily generalized epilepsy, might predict a favorable surgical outcome of corpus callosotomy in patients of HME, as in our case.
    Brain & development 05/2008; 30(10):643-6. · 1.74 Impact Factor
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    ABSTRACT: The magnetic equivalent (MMNm) of mismatch negativity may reflect auditory discrimination and sensory memory. To study whether temporal lobe epilepsy (TLE) affects automatic central auditory-change processing, we recorded magnetoencephalographic (MEG) responses to standard and duration-deviant sounds in 12 TLE patients and 12 age-matched controls, and repeated MEG measurement in 8 patients 6-30 months following epilepsy surgery and in 6 controls 3-8 months after their first measurement. We compared the MMNm between patients and controls, and also evaluated intertrial phase coherences as indexed by phase-locking factors (PLF) using wavelet-based analyses. We observed longer MMNm latencies for patients than for controls. Dipole modeling and minimum-current estimates together showed bi-frontotemporal sources for MMNm. The phase locking across trials was dominant at the 4- to 14-Hz band, and the main difference in PLF between deviant- and standard-evoked responses occurred in the time frame of 150-250 ms after stimulus onset. Notably, in the 5 patients who became seizure free after removal of right temporal epileptic focus, the phase-locking phenomena resulting from deviant stimuli were enhanced, and even more distributed in the frontotemporal regions. We conclude that mesial TLE might affect auditory-change detection, and a successful surgery causes a possible plastic change in phase locking of deviant-evoked signals.
    Cerebral Cortex 12/2007; 17(11):2516-25. · 8.30 Impact Factor
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    ABSTRACT: This retrospective study was designed to clarify the role of West syndrome in post-callosotomy seizure outcome in patients with Lennox-Gastaut syndrome. 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. 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. A history of West syndrome does not appear to influence post-callosotomy seizure outcome in patients with Lennox-Gastaut syndrome.
    Seizure 11/2006; 15(7):552-7. · 2.00 Impact Factor
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    ABSTRACT: 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.
    Journal of the Chinese Medical Association 11/2006; 69(10):496-8. · 0.75 Impact Factor
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    ABSTRACT: To evaluate whether the selective posterior cerebral artery amobarbital test (PCAAT) can predict postoperative memory function in patients with temporal lobe epilepsy (TLE) for surgical treatment and its clinical safety. The database included adult patients with intractable TLE undergoing presurgical evaluation at Taipei Veterans General Hospital between 1995 and 2002. The PCAAT was carried out on patients who had failed conventional intracarotid amobarbital test (IAT) or had IAT results that evoked a concern of postoperative memory function decline. A battery of learning and memory testing was performed immediately before and after injection of amobarbital into the peduncular segment of the posterior cerebral artery (PCA) on the presumed hemisphere of epileptogenicity. Neuropsychological assessments were followed in surgically treated patients. A total of 16 patients completed PCAAT successfully and underwent anterior temporal lobectomy (ATL). Four patients failed PCAAT angiographic procedures due to technical difficulty in one patient, transient signs of vasospasm in two patients, and subarachnoid hemorrhage in one patient. Of the 12 patients who performed well in PCAAT learning and memory testing items by free recall or recognition, only 1 patient demonstrated postoperative memory decline in follow-up neuropsychological assessments. In contrast, two of the four patients with a deficit in PCAAT memory testing showed postoperative memory decline. Regarding subjective memory function (not necessarily associated with objective memory decline), patients not seizure-free after ATL were more likely to have memory complaints (in 3 out of 6 patients) than patients with seizure-free outcomes (in 1 out of 10 patients). The PCAAT memory test reliably predicts postoperative memory function in patients with TLE for surgical treatment. However, the inherent risks of PCAAT must be considered and it should be used judiciously.
    Seizure 04/2006; 15(2):117-24. · 2.00 Impact Factor
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    ABSTRACT: 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. 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. 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). 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.
    Seizure 11/2005; 14(7):470-5. · 2.00 Impact Factor
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    ABSTRACT: 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.
    Acta neurologica Taiwanica 10/2004; 13(3):136-48.
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    ABSTRACT: 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.
    Seizure 11/2003; 12(7):448-55. · 2.00 Impact Factor
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    ABSTRACT: The aim of this study is to evaluate the medication knowledge achieved by conventional verbal education and the influence of drug information leaflets in patients with epilepsy. Drug compliance and sources of information of the patients were also examined. Fifty-one adults in an epilepsy outpatient clinic participated this survey. These patients were asked to complete a questionnaire and to specify sources of drug information. Serum drug levels were checked and compared with the self-reported compliance. Then, drug information leaflets were given to patients. In the next follow-up visit, patients were asked to fill out the same questionnaire again. In the baseline assessment, 36 patients (70.6%) could accurately list their medications. However, half of patients were not knowledgeable about side effects and did not keep a seizure diary. After provision of drug leaflets, the epilepsy medication assessment score increased from 3.9 +/- 1.9 to 5.1 +/- 1.7 (P<0.001). In addition, patients reported being compliant most of the time and this matched drug levels. On average, each patient had 2.8 sources of information and 5 patients used Internet as a tool. Despite achieving good compliance, conventional verbal education did not sufficiently cover drug-related issues. Providing patients with written information apparently increase their medication knowledge and probably enhance seizure control.
    Seizure 11/2003; 12(7):473-7. · 2.00 Impact Factor
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    ABSTRACT: Structural lesions are found in about 30% of surgical specimens resected for intractable temporal lobe epilepsy (TLE). Detailed presurgical evaluations can identify the epileptogenic foci, the structural lesions and their correlation. Different surgical approaches have variable seizure control outcomes. The preoperative investigations for the intractable TLE consisted of serial electroencephalogram (EEG) recordings, long-term EEG/video monitoring with sphenoidal electrodes, magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), positron emission tomography with fluorodeoxyglucose (FDG-PET) and neuropsychological assessment. Among the 217 patients who underwent anterior temporal lobectomy (ATL) for TLE at Taipei Veterans General Hospital between 1987 and 1998, 47 (21.7%) had structural lesions in the resected specimen. The patients were divided into neoplastic (n = 35) and vascular (n = 12) groups, based on the pathological findings. In the neoplastic group, the interictal scalp-sphenoidal EEG recordings were abnormal in all 35 cases and lateralizing in 30 (85.7%). MRI revealed tumor growth within the temporal lobe in 26 patients (74.3%). FDG-PET was performed on 17 patients. Fifteen (88.2%) of them revealed unilateral mesial temporal lobe hypometabolism. In the vascular group, the interictal EEG tracings revealed unilateral mesial temporal lobe spikes in 11 patients (91.6%). MRI revealed abnormal enhanced lesions within the temporal lobes in all 12 patients. FDG-PET was available for 7 patients, 6 (86%) of whom had unilateral mesial temporal lobe hypometabolism. At the last follow-up (range 2-10 years, with a mean period of 4.2 years), 25 patients (73%) in the neoplastic group became and remained seizure-free postoperatively, 3 (9%) had fewer than 3 attacks per year. Among the vascular group, all 12 patients became and remained seizure-free after surgery. For intractable TLE with structural lesions, detailed presurgical evaluations are mandatory to identify the concordance of the lesions and the epileptogenic foci. Standard ATL with removal of the lesion may offer good seizure control postoperatively.
    Journal of the Chinese Medical Association 11/2003; 66(10):565-71. · 0.75 Impact Factor
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    ABSTRACT: To investigate olfactory auras in patients with temporal lobe epilepsy (TLE). We reviewed medical records of 217 Chinese patients who underwent temporal lobectomy for medically intractable TLE between 1987 and 1998 in Taiwan. Patients with olfactory auras asked for detailed characteristics of their auras. In all, 12 (5.5%) patients had olfactory auras, seven men and five women. All patients except one described and characterized the unpleasant olfactory auras. Olfactory auras were usually combined with other auras, most frequently sensations of epigastric rising, nausea, and fear. Association with gustatory hallucination was uncommon, in only one patient. On neuroimaging study, 11 patients had structural lesions involving the mesial temporal structures, two exclusively involving the amygdala. Histologic diagnosis included gliosis of the mesial temporal regions in seven (58.3%) patients, neoplasm in four (33.3%) patients, and arteriovenous malformation in one patient. Postoperatively, eight patients were seizure free. Three patients had rare seizures; however, none reported residual olfactory auras. Olfactory auras are infrequent in TLE. In this study, mesial temporal sclerosis is the most common etiology rather than tumors. Mesial temporal structures, especially the amygdala, may play important roles in the genesis of olfactory auras.
    Epilepsia 03/2003; 44(2):257-60. · 3.91 Impact Factor
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    ABSTRACT: We evaluated the lateralizing value of ictal upper extremity movements in temporal lobe epilepsy (TLE). Videotapes of 259 complex partial seizures from 83 patients who became seizure-free after anterior temporal lobectomy were retrospectively studied. Pathologic diagnosis included hippocampal sclerosis in 73 patients and “lesional” in 10 patients. Ictal upper extremity movements were arbitrarily classified into four categories including dystonic posturing, tonic posturing, hand automatisms, and immobility. Dystonic posturing occurred in 86 seizures (33.2%) from 29 patients (34.9%), which included 28 hippocampal sclerosis and only one (3.4%) lesional. In all seizures except one (98.8%), dystonic posturing was unilateral and contralateral to the seizure focus (p < 0.001). Tonic posturing was observed in 64 seizures (24.7%), 48 unilateral and 16 bilateral, from 31 patients (37.3%). Tonic posturing did not lateralize the seizure focus (p = 0.477) or tend to secondarily generalize (p = 0.757). Unilateral or bilateral hand automatisms occurred in 188 seizures (72.6%) from 71 patients (85.5%). From 113 seizures with unilateral hand automatisms, 105 (92.9%) originated from the ipsilateral temporal lobe (p < 0.001). Immobility of the upper extremities was found in 64 seizures (24.7%) and appeared not to lateralize.
    Journal of Epilepsy 01/1998; 11(6):314-318.

Publication Stats

122 Citations
44.02 Total Impact Points

Institutions

  • 1995–2012
    • Taipei Veterans General Hospital
      • • Division of Neurology
      • • Neurological Institute
      T’ai-pei, Taipei, Taiwan
  • 2011
    • Taoyuan Armed Forces General Hospital
      Hsin-chu-hsien, Taiwan, Taiwan
  • 1998–2008
    • National Yang Ming University
      • Department of Neurology
      T’ai-pei, Taipei, Taiwan
  • 2004
    • Taoyuan General Hospital
      Taoyuan City, Taiwan, Taiwan