Shih-Tseng Lee

Chang Gung Memorial Hospital, T’ai-pei, Taipei, Taiwan

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Publications (96)119.08 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: Arteriovenous malformation (AVM) is one of the cerebrovascular diseases that bear a high risk of hemorrhage. The treatment modalities include microsurgical resection, endovascular embolization, stereotactic radiosurgery, or combinations that vary widely. Several large series have been reported, while data from Asian populations were few. The aim of this study was to examine the efficacy of linear accelerator stereotactic radiosurgery (LINAC SRS) for the treatment of intracranial AVMs, to evaluate the hemorrhage rate and to analyze associated factors. Methods: One hundred and sixteen patients with AVM were treated with LINAC SRS in a single institute between September 1994 and May 2005 and were retrospectively evaluated. The demographics of patients, clinical characteristics of AVM, the treatment modalities, and the parameters of the LINAC SRS were analyzed. Delayed toxicity and hemorrhage rate after treatment were also evaluated. The AVM obliteration and bleed rates were calculated using the Kaplan-Meier method and Cox regression analyses. Results: The efficacy rate with total obliteration after treatment was 81.9% (95 of 116 patients). The median interval to achieve total obliteration was 49 months. Microsurgical resection combined with SRS for residual AVMs achieved better obliteration rates compared to SRS alone (statistically significant, p = 0.001), while no significant difference was found between the embolization group and the group with no prior treatment (p = 0.895). The Spetzler-Martin grade of AVM is a relative factor of obliteration, higher grades resulting in a worse outcome (p = 0.009). Obliteration was significantly influenced by AVM volume in univariate analysis (p = 0.034), and volume <5 cm(3) contributed to improved obliteration (p = 0.01). There was no statistically significant difference in the hemorrhagic rate and the complication rate between ruptured and unruptured AVMs, while the unruptured group had a higher obliteration rate (p = 0.024). The annual hemorrhage rate after LINAC SRS treatment was 1.9%. The bleeding rate was 3.3% in the first year after radiosurgery, 2.1% in the second year, 1.9% between the second and fifth year, and 1.5% between the fifth and tenth year. Patients with hemorrhagic events before radiosurgery appeared to have a higher rebleeding risk during the latency period. Twenty-three patients (19.8%) had late adverse effects with regard to posttreatment radiological follow-up, but only 1 (0.8%) had newly developed neurological deficits. Conclusion: LINAC SRS achieved a high obliteration rate and reduced the risk of hemorrhage effectively in ruptured and unruptured intracranial AVMs. Prior microsurgical resection provided better outcome, while embolization showed no benefit. Adverse effects after treatment are acceptable and require long-term follow-up. © 2014 S. Karger AG, Basel.
    Cerebrovascular diseases (Basel, Switzerland). 06/2014; 37(5):342-349.
  • Po-Chuan Hsieh, Shih-Tseng Lee, Jyi-Feng Chen
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    ABSTRACT: Degenerative spondylolisthesis of the spine is less common in the lower thoracic region than in the lumbar and cervical regions. However, lower thoracic degenerative spondylolisthesis may develop secondary to intervertebral disc degeneration. Most of our patients are found to have concomitant lumbar spondylosis. By retrospective review of our cases, current diagnosis and treatments for this rare disease were discussed. We present a series of 5 patients who experienced low back pain, progressive numbness, weakness and even paraparesis. Initially, all of them were diagnosed with lumbar spondylosis at other clinics, and 1 patient had even received prior decompressive lumbar surgery. However, their symptoms continued to progress, even after conservative treatments or lumbar surgeries. These patients also showed wide-based gait, increased deep tendon reflex (DTR), and urinary difficulty. All these clinical presentations could not be explained solely by lumbar spondylosis. Thoracolumbar spinal magnetic resonance imaging (MRI), neurophysiologic studies such as motor evoked potential (MEP) or somatosensory evoked potential (SSEP), and dynamic thoracolumbar lateral radiography were performed, and a final diagnosis of lower thoracic degenerative spondylolisthesis was made. Bilateral facet effusions, shown by hyperintense signals in T2 MRI sequence, were observed in all patients. Neurophysiologic studies revealed conduction defect of either MEP or SSEP. One patient refused surgical management because of personal reasons. However, with the use of thoracolumbar orthosis, his symptoms/signs stabilized, although partial lower leg myelopathy was present. The other patients received surgical decompression in association with fixation/fusion procedures performed for managing the thoracolumbar lesions. Three patients became symptom-free, whereas in 1 patient, paralysis set in before the operation; this patient was able to walk with assistance 6 months after surgical decompression. The average Nurick scale score improved from 3.75 before the operation to 2 after the operation. Lower thoracic degenerative spondylolisthesis is a rare disease, which may occur concomitantly with lumbar spondylosis and confuse clinicians. Diagnosis should be made properly, especially because symptoms/signs cannot be explained purely on the basis of the available images. Micromotion due to facet joint laxity and disc degeneration was believed as the cause of progressive myelopathy. Posterior decompression with fixation/fusion procedure was appropriate for the treatment of thoracic spondylolisthesis secondary to thoracic disc degeneration.
    Clinical neurology and neurosurgery 03/2014; 118C:21-25. · 1.30 Impact Factor
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    ABSTRACT: This work investigates the calibration of a stereo vision system based on two PTZ (Pan-Tilt-Zoom) cameras. As the accuracy of the system depends not only on intrinsic parameters, but also on the geometric relationships between rotation axes of the cameras, the major concern is the development of an effective and systematic way to obtain these relationships. We derived a complete geometric model of the dual-PTZ-camera system and proposed a calibration procedure for the intrinsic and external parameters of the model. The calibration method is based on Zhang's approach using an augmented checkerboard composed of eight small checkerboards, and is formulated as an optimization problem to be solved by an improved particle swarm optimization (PSO) method. Two Sony EVI-D70 PTZ cameras were used for the experiments. The root-mean-square errors (RMSE) of corner distances in the horizontal and vertical direction are 0.192 mm and 0.115 mm, respectively. The RMSE of overlapped points between the small checkerboards is 1.3958 mm.
    01/2014;
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    ABSTRACT: Objective This study uses a validated learning style inventory to delineate the learning style that best defines a successful practitioner in the field of neurosurgery. Methods The Kolb Learning Style Inventory (LSI), a validated assessment tool, was administered to all practicing neurosurgeons, neurosurgical residents, and neurology residents employed at Chang Gung Memorial Hospital, an institution that provides both primary and tertiary clinical care, in three locations, Linkou, Kaohsiung, and Chiayi. Eighty-one participants entered the study and all completed the study. Results Neurosurgeons preferred the assimilating learning style (52%), followed by the diverging learning style (39%). Neurosurgery residents were slightly more evenly distributed across the learning styles, however, they still favored assimilating (32%) and diverging (41%). Neurology residents had the most clearly defined preferred learning style with assimilating (76%) obtaining the large majority, and diverging (12%) being a distant second. Conclusions The assimilating and diverging learning styles are the preferred learning styles among neurosurgeons, neurosurgery residents, and neurology residents with the assimilating learning style typically being the primary learning style for neurosurgeons and neurology residents. Neurosurgical residents start off with a diverging learning style and progress towards an assimilating learning style as they works towards becoming practicing neurosurgeons. The field of neurosurgery has limited opportunities for active experimentation which may explain why individuals that prefer reflective observation are more likely to succeed in this field.
    World Neurosurgery 01/2014; · 1.77 Impact Factor
  • Article: Response.
    Ching-yi Lee, Shih-Tseng Lee
    Journal of neurosurgery. Spine 12/2013; 19(6):795. · 1.61 Impact Factor
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    ABSTRACT: Anterior cervical disectomy and fusion (ACDF) is a highly effective and safe method for spinal cord and cervical root decompression. However, vocal cord paralysis (VCP) remains an important cause of postoperative morbidity. The true incidence and recovery course of postoperative VCP is still uncertain. This study is a report on VCP after ACDF to evaluate the incidence, recovery course, and possible risk factors. From 2004 to 2008, 1,895 consecutive patients underwent ACDF in our hospital and were followed up for at least 3 years. All surgeons were well trained and used a right-sided exposure. Prolonged VCP, where patients suffered from postoperative VCP lasting more than 3 months, was recorded and analyzed. In this retrospective study, 9 of the 1,895 patients (0.47 %) documented prolonged VCP lasting over 3 months. Six of the nine patients had total recovery within 9 months. Only three patients (0.16 %) still had symptoms even after 3 years postoperatively. All symptoms of VCP, except hoarseness, could be improved. After matching with 36 non-VCP patients, no differences with regard to longer operative or anesthesia time, shorter neck, obesity, and prevertebral edema. All cases of prolonged course of postoperative VCP occurred in patients who underwent exposure at the C67 level. In our study, only 0.47 % documented prolonged postoperative VCP, while most patients recovered within 9 months. However, if symptoms last longer, there could be almost permanent VCP (0.16 %). In our study, choking and dysphagia subsided mostly within 6 months, but hoarseness remained. The exposure of the C67 level obviously was a risk factor for postoperative VCP.
    European Spine Journal 11/2013; · 2.47 Impact Factor
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    ABSTRACT: Primitive neuro-ectodermal tumors (PNET) are rare malignant brain tumors, mostly undifferentiated, that tend to spread through the cerebrospinal fluid (CSF). Extra-pineal supratentorial PNET in adults are very rare. Published guidelines for adult PNET were not available until 2011, and at our institute surgeons and oncologists did not have consensus on imaging evaluation or treatment protocols between 1994 to 2008. Twenty-two consecutive adult patients with extra-pineal supratentorial PNET from this period were reviewed in this retrospective study. Their clinical profiles and radiologic images were evaluated. A pathological review based on the 2007 World Health Organization criteria was also conducted. Prognostic factors were analyzed. The 1 and 3year overall survival rates were 64% and 32% for adult extra-pineal supratentorial PNET, respectively. Limited by the small number of tumors in this series, we suggest that negative prognostic factors are multiplicity at onset, initial CSF seeding, and tumor differentiation. Although age of onset, extent of resection, radiation and chemotherapy were assumed to be good prognostic factors, the analysis did not reveal strong significance for overall survival with univariate and multivariate analysis. We believe more detailed investigations on the genetic/molecular basis of supratentorial PNET and their clinical outcomes are warranted.
    Journal of Clinical Neuroscience 10/2013; · 1.25 Impact Factor
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    ABSTRACT: Radiosurgery has been proven to be an effective treatment for residual or recurrent pituitary adenomas after surgery. However, it causes severe complications when the optic apparatus is irradiated over the tolerance dose. In this study, we analyzed the feasibility of fractionated stereotactic radiosurgery to treat pituitary tumors close to the optic apparatus. Thirty-four patients from June 2006 to June 2011 with recurrent or residual pituitary adenomas close to (<3mm) the optic apparatus were treated with fractionated stereotactic radiosurgery. Three fractions with a total dose of 2100cGy were applied to the tumors. Imaging, examination of vision, and estimation of hormone level were regularly performed before and after radiosurgery. The mean tumor volume before fractioned stereotactic radiosurgery was 5.06±3.08cm(3) (range: 0.82-12.69cm(3)). After a mean follow up of 36.8±15.7months (range: 16-72months), tumor size was reduced in seven (20.6%) patients and remained the same in the other 27 (79.4%) patients. Vision was improved in one patient and remained stable in the rest. Only one patient developed transient post-treatment diplopia. This study suggests that fractionated stereotactic radiosurgery is safe for treating pituitary adenomas close to the optic apparatus. Studies with more patients and longer follow-up are required to draw definite conclusions.
    Journal of Clinical Neuroscience 09/2013; · 1.25 Impact Factor
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    ABSTRACT: Study Design: Case report.Objective: To report a case of lumbar intraneural hemorrhagic cyst after anticoagulation therapy that caused progressive radiculopathy and cauda equina syndrome. The possible pathogenic mechanism, associated diseases, and treatment options are discussed.Summary of Background Data: Various pathologic processes can cause progressive cauda equina syndrome. However, there have been no reports of progressive cauda equina syndrome due to compression from an intraneural hemorrhagic cyst after anticoagulation therapy.Methods: A case of lumbar intradural intraneural hemorrhagic cyst with progressive cauda equina syndrome after anticoagulation therapy is presented.Results: A 42-year-old female patient complained atpresentation of progressive bilateral lower extremity radiating pain, numbness and urinary difficulty during the previous 2 months. Lumbar magnetic resonance imaging (MRI) revealed an L1 cystic lesion with marked mass effect on the surrounding nerve roots. Complete drainage and excision of the lesion was performed which resulted in excellent postoperative symptoms relief. Pathologic examination revealed no definite neoplastic process except some nerve fibers with hemosiderin stain along the cyst wall. Based on a combination of intraoperative findings and pathology, an intradural intraneural hemorrhagic cyst that developed after systemic anticocagulation therapy was diagnosed.Conclusion: This is the first report of an intradural intraneural hemorrhagic cyst causing progressive cauda equina syndrome due to anticoagulation therapy. Surgical excision of the cyst is the definite treatment of choice.
    Spine 09/2013; 38(20):E1288-90. · 2.16 Impact Factor
  • Ching-Yi Lee, Hung-Yi Lai, Shih-Tseng Lee
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    ABSTRACT: Ganglion cysts of the cruciate ligament are rare and sometimes asymptomatic. The authors present three cases of ganglion cysts of the cruciate ligament with atlantoaxial subluxation, which has rarely been reported previously. Generally, ganglion cysts of the cruciate ligament are reported as case reports. Several theories regarding the process of cyst formation and the development of treatment options have been described. However, trans-oral decompression with total removal of the cyst may be one of the options for treatment of this kind of disease. A retrospective review of three patients, two female and one male patient, with a mean age of 68 years was conducted. The operation performed was a trans-oral decompression with cyst removal for all patients. Clinical outcomes were evaluated after the operation. All patients underwent trans-oral decompression with total removal of the cyst, followed by posterior fusion and pathologic examination of the cyst, revealing myxoid stroma with an absence of synovial linings. The ganglion cysts and synovial cysts of the cruciate ligament are two different diseases with different presentation, pathogenesis, pathophysiology, and pathologic findings.
    Acta Neurochirurgica 08/2013; · 1.55 Impact Factor
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    ABSTRACT: Balloon test occlusion (BTO) is crucial before sacrificing parent arteries. We proposed a simple paradigm combining clinical tolerance with venous phase technique and stump pressure ratio as a criterion for sufficient collateral flow. Internal carotid artery (ICA) occlusion was considered safe for asymptomatic patients who exhibited less than 2 seconds of venous phase delay or had a stump pressure ratio greater than 60%. A total of 37 BTO procedures were performed on 31 patients. Twenty-three patients were monitored clinically and 3 were symptomatic. Venous phase comparison was performed on 27 patients, and 5 failed the test. The stump pressure was measured in all patients, and 7 patients failed the test. In summary, 7 patients failed the BTO, of which 6 received high-flow bypass and 1 of these 6 were symptomatic and exhibited stump pressure ratios less than 60% in the second BTO procedure. Occlusion of the ICA was performed on 29 patients. Only 1 patient developed delayed vasospasm and brain infarction. Adequate collateral flow may be indicated by a stump ratio of 60% or greater with or without a high-flow bypass. Combined with clinical assessment and venous phase technique, ICA occlusion may be a safe option that does not result in delayed ischemic complications.
    Journal of stroke and cerebrovascular diseases: the official journal of National Stroke Association 07/2013;
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    ABSTRACT: In cranioplasty, neurosurgeons use bone grafts to repair skull defects. To ensure the protection of intracranial tissues and recover the original head shape for aesthetic purposes, a custom-made pre-fabricated prosthesis must match the cranial incision as closely as possible. In our previous study (Liao et al. in Med Biol Eng Comput 49:203-211, 2011), we proposed an algorithm consisting of the 2D snake and image registration using the patient's own diagnostic low-resolution and defective high-resolution computed tomography (CT) images to repair the impaired skull. In this study, we developed a 3D multigrid snake and employed multiresolution image registration to improve the computational efficiency. After extracting the defect portion images, we designed an image-trimming process to remove the bumped inner margin that can facilitate the placement of skull implants without manual trimming during surgery. To evaluate the performance of the proposed algorithm, a set of skull phantoms were manufactured to simulate six different conditions of cranial defects, namely, unilateral, bilateral, and cross-midline defects with 20 or 40 % skull defects. The overall image processing time in reconstructing the defect portion images can be reduced from 3 h to 20 min, as compared with our previous method. Furthermore, the reconstruction accuracies using the 3D multigrid snake were superior to those using the 2D snake.
    Medical & Biological Engineering 10/2012; · 1.76 Impact Factor
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    ABSTRACT: Decompressive craniectomy has been considered the most attractive option for surgical treatment of malignant middle cerebral artery (MCA) infarction. We retrospectively reviewed the clinical and radiological records of 78 patients with malignant MCA infarction who underwent decompressive craniectomy with dura augmentation over a 6-year period. Twenty-six patients had undergone additional anterior temporal resection during decompressive craniectomy. The overall mortality at 30days after surgery was 25.6% while the mortality rate at 6months after surgery was 30.8%. At 6months after surgery, 30.8% of the patients were considered to have good outcomes, while 69.2% had a poor outcome (16.7% suffered from severe disability, 21.8% remained in a vegetative state, and 30.8% died). Ipsilateral surgery was performed on 48 patients with infarction on the dominant side and on 30 patients with lesions on the non-dominant side. No significant difference was noted between these two groups at the 30-day mortality rate. Although no patient with an infarction on the dominant side recovered effective verbal ability during the 6months of follow-up, there was no significant difference between the two groups in clinical outcome at 6months after surgery. The 30-day survival rate in the 26 patients who underwent additional anterior temporal lobectomy was significantly higher (84.6%) than that in patients who underwent decompressive craniectomy and duroplasty only (69.2%) (p<0.05). However, in patients who survived, this additional procedure does not appear to improve the functional outcome.
    Journal of Clinical Neuroscience 10/2012; · 1.25 Impact Factor
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    ABSTRACT: In this paper, we propose an application of augmented reality technology for targeting tumors or anatomical structures inside the skull. The application is a combination of the technologies of MonoSLAM (Single Camera Simultaneous Localization and Mapping) and computer graphics. A stereo vision system is developed to construct geometric data of human face for registration with CT images. Reliability and accuracy of the application is enhanced by the use of fiduciary markers fixed to the skull. The MonoSLAM keeps track of the current location of the camera with respect to an augmented reality (AR) marker using the extended Kalman filter. The fiduciary markers provide reference when the AR marker is invisible to the camera. Relationship between the markers on the face and the augmented reality marker is obtained by a registration procedure by the stereo vision system and is updated on-line. A commercially available Android based tablet PC equipped with a 320×240 front-facing camera was used for implementation. The system is able to provide a live view of the patient overlaid by the solid models of tumors or anatomical structures, as well as the missing part of the tool inside the skull.
    Proc SPIE 10/2012;
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    ABSTRACT: Intracranial electroencephalograms (EEG) provide a direct observation of neural activity by placing an electrode array on the cortical surface near the suspected epileptic foci. The neural spikes appeared during inter-ictal stages are mainly produced by abnormal neural discharges from epileptic foci. The topological mapping of spikes' potentials is commonly used to identify the epileptogenic zone. However, the propagations among multi-channel spikes are also important to identify the epileptic source activity. In addition, the changes of source activities in a series of consecutive spikes reveal the time-varying neural activations during discharge process, which provide alternative information for interpreting epileptic source activity. This paper proposes a spike classification based on the similarity of phase-space features to select candidate spikes from the intracranial EEGs recorded from an 8×8 electrocorticogram grid. Then, the partial directed coherence (PDC), which can provide the flow of source activity, at each spiking time point is computed. The outflow PDCs of all electrodes are therefore displayed on the grid. Our result showed that the derived source activities in the preceding spikes had high concentrated distributions but decreased in latter spikes. This implied the epileptic discharges were initially induced by a small-area cortex neurons and then spread out.
    Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 08/2012; 2012:5174-7.
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    ABSTRACT: Liver cirrhosis was identified as an independent predictor of poor outcomes in patients suffering trauma and in those undergoing major surgeries. The aim of this study was to report the authors' experiences treating patients with cirrhosis who undergo brain surgeries. Between 2004 and 2009, 121 consecutive patients with cirrhosis underwent 144 brain procedures. Patients were categorized as Child-Turcotte-Pugh (referred to as "Child") Class A, B, or C. The patient profiles, including the severity of cirrhosis, reason for surgery, complications, and prognosis factors, were analyzed. In this retrospective study, the overall surgical complication rate for patients with cirrhosis was 52.1% and the mortality rate was 24.3%. For patients with acute traumatic brain injury (TBI), the complication, rebleeding, and mortality rates reached 84.4%, 68.8%, and 37.5%, respectively. Surgery for TBI was a significant risk factor for postoperative complications (p = 0.0002) and postoperative hemorrhage (p < 0.0001). Otherwise, according to the Child classification, the complication rate increased in a stepwise fashion from 38.7% to 60% to 84.2%, the rebleeding rate from 29.3% to 48.0% to 63.2%, and the mortality rate from 5.3% to 38% to 63.2% for Child A, B, and C, respectively. The Child classification was associated with higher risk of complications-Child B vs A OR 2.84 (95% CI 1.28-6.29), Child C vs A OR 5.39 (95% CI 1.32-22.02). It was also associated with risk of death-Child C vs A OR 30.43 (95% CI 7.71-120.02), Child B vs A OR 10.88 (95% CI 3.42-34.63). Liver cirrhosis is a poor comorbidity factor for brain surgery. The authors' results suggest that the Child classification used independently is a poor prognostic factor; in addition, grave outcomes were observed in patients with TBI.
    Journal of Neurosurgery 05/2012; 117(2):348-53. · 3.15 Impact Factor
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    ABSTRACT: Percutaneous vertebroplasty (PVP) has played an increasing role in the treatment of osteoporotic compression fracture. The number of prior vertebral fractures and prior vertebroplasties are important risk factors for future fractures. We prospectively evaluated the effectiveness of teriparatide therapy for 28 patients who had repeated and multiple new-onset vertebral compression fractures (VCF). None of the patients required PVP or experienced a new-onset vertebral fracture during the treatment and follow-up period of at least 18 months. Teriparatide therapy significantly decreased visual analogue scale pain scores, increased Japanese Orthopaedic Association function scores, increased spinal bone mineral density, and prevented new-onset VCF. Teriparatide can be used in patients who have repeated and multiple new-onset painful VCF to avoid repeated vertebroplasty. Therapy should continue for at least six months to ensure it is effective.
    Journal of Clinical Neuroscience 04/2012; 19(4):532-5. · 1.25 Impact Factor
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    ABSTRACT: Decompressive hemicraniectomy (DC) can save the lives of patients with malignant middle cerebral artery (MCA) infarction. We proposed that postoperative midline shift is important for the long-term outcome of patients with MCA infarction. We conducted a retrospective study of DC in 38 patients with malignant MCA infarction. The long-term outcome was assessed one year after surgery using the modified Rankin Scale (mRS) score. Patients who had midline shift less than the optimal diagnostic cut-off point on the fourth postoperative day were classified as having a successful decompression and the remaining patients were classified in the failed decompression group. The successful decompression group mRS score was 4.20±0.89 one year after surgery and the failed decompression group mRS score was 5.11±0.76 (p<0.0001). Successful decompression, resulting in postoperative midline shift of less than 5mm, was a key factor for beneficial, long-term functional outcomes in patients with malignant MCA infarction.
    Journal of Clinical Neuroscience 02/2012; 19(5):661-4. · 1.25 Impact Factor
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    ABSTRACT: Glioblastoma multiforme (GBM) is the most aggressive type of primary brain tumor. It is a rapidly progressive, highly recurrent, fatal intracranial neoplasm, and the demand for novel treatment is urgent. Valproic acid (VPA) is a potential anticancer agent that belongs to a class of histone deacetylase (HDAC) inhibitors, targeting the epigenetic control of gene functions in cancer cells. This drug has been administered for the prevention or treatment of seizure disorder in GBM patients; therefore, a retrospective analysis may further our understanding of the effect of VPA on GBM patients. A retrospective analysis of 102 patients with GBM was conducted to study the effects of VPA on disease outcome. Tumor samples from seven patients receiving VPA treatment between the first and second operations were obtained in order to verify the HDAC inhibitory activity of VPA in these patients. In univariate analysis, administration of VPA within 2 weeks of initial diagnosis seemed to confer a survival benefit. However, stratified analysis according to chemotherapy showed that VPA did not have significant impact on the GBM patients' overall survival. Analysis of tissue samples from these patients revealed that a small subset of patients had increased histone acetylation after VPA treatment. VPA treatment, when administered according to a protocol targeting seizure control, may result in HDAC inhibition in a small subset of patients, but does not significantly affect overall patient survival. Early administration of VPA as an adjunct to temozolomide chemotherapy may have its merits, but the optimal dosing schedule and target serum level require further investigation.
    British Journal of Neurosurgery 12/2011; 26(3):347-54. · 0.86 Impact Factor
  • Jyi-Feng Chen, Po-Hsun Tu, Shih-Tseng Lee
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    ABSTRACT: This study aimed to evaluate the outcomes and complication rates associated with percutaneous balloon compression (PBC) for trigeminal neuralgia for a 10-year follow-up period. A total of 185 patients with trigeminal neuralgia were treated with an initial PBC between July 2000 and December 2001 and were followed up until July 2010. PBC was performed under general anesthesia with endotracheal intubation. Meckel's cave was cannulated with a No. 4 Fogarty catheter, and the balloon was inflated for 70-90 seconds. Treatment and long-term follow-up was completed for 130 of the 185 patients. The mean length of the follow-up period was 8.9 years. Sixty-two patients (47.7%) were 65 years of age or older. Seventy-eight patients (60%) had pain involving the ophthalmic or multiple trigeminal divisions. One hundred twenty-two patients (93.8%) experienced immediate relief from neuralgia after the procedure. No pain recurred within 3 months. Seventeen patients (14%) had recurrent symptoms within 2 years. Twenty-three patients (18.9%) had recurrent symptoms within 3 years. Thirty-six patients (29.5%) had recurrent symptoms within 5 years. A total of 46 patients (37.7%) had recurrent symptoms during the entire study period. PBC is a technically simple, less painful procedure carried out under brief general anesthesia and is well tolerated by patients. The operation success rate is high, and the recurrence rate is similar to that of other reports. We also found that longer compression time resulted in longer symptom-free periods.
    World Neurosurgery 12/2011; 76(6):586-91. · 1.77 Impact Factor

Publication Stats

553 Citations
119.08 Total Impact Points

Institutions

  • 1986–2014
    • Chang Gung Memorial Hospital
      • Division of Neurosurgery
      T’ai-pei, Taipei, Taiwan
  • 2002–2011
    • Chang Gung University
      • • College of Medicine
      • • Department of Medical Imaging and Radiological Sciences
      Taoyuan, Taiwan, Taiwan