Yen-Heng Lin | National Taiwan University (original) (raw)

Papers by Yen-Heng Lin

Journal of Vascular and Interventional Radiology, Jul 1, 2023

European Journal of Radiology, Jun 1, 2023

Epilepsy & behavior reports, 2023

Journal of Vascular and Interventional Radiology, May 1, 2020

Purpose: To compare clinical characteristics and treatment outcomes of intraarterial thrombectomy... more Purpose: To compare clinical characteristics and treatment outcomes of intraarterial thrombectomy (IAT) in acute basilar artery occlusion (BAO) with and without underlying intracranial atherosclerotic stenosis (ICAS) and to investigate the usefulness of preprocedural CT angiography findings in the diagnosis of ICAS. Materials and Methods: Twenty patients who received IAT for acute BAO between September 2014 and March 2019 were included. Additional therapies such as angioplasty, stent placement, and tirofiban infusion were provided while treating ICAS. Clinical and angiographic results of treatment were recorded. Preprocedural CT angiography findings in ICAS and non-ICAS groups were compared to assess (i) basilar tip opacification, (ii) partial occlusion, (iii) presence of convex border, (iv) occlusion segment longer than two thirds of the basilar artery or 20 mm, (v) dense basilar artery, and (vi) wall calcification in the occluded segment. Results: Among the 20 patients (mean age, 71.3 y; mean stroke score, 24.8), optimal recanalization was achieved in 19 (95%). Three patients had good clinical outcomes. There were 6 patients with underlying ICAS. No difference was observed between ICAS and non-ICAS groups in terms of optimal angiographic recanalization and good outcome. On CT angiography, basilar tip occlusion (100% vs 29%), partial occlusion (100% vs 83%), and long occlusion length (100% vs 14%) significantly differed between the groups (P .01). Conclusions: In acute BAO, underlying ICAS does not affect optimal recanalization rate or clinical outcome. Preprocedural CT angiography is a potentially useful tool to detect it.

American Journal of Neuroradiology, May 17, 2018

BACKGROUND AND PURPOSE: Permanent common carotid artery and/or ICA occlusion is an effective trea... more BACKGROUND AND PURPOSE: Permanent common carotid artery and/or ICA occlusion is an effective treatment for carotid blowout syndrome. Besides postoperative thromboembolic infarction, permanent common carotid artery and/or ICA occlusion may cause borderzone infarction when the collateral flow to the deprived brain territory is inadequate. In this study, we aimed to test the predictive value of CTA for post-permanent common carotid artery and/or ICA occlusion borderzone infarction in patients with carotid blowout syndrome. MATERIALS AND METHODS: In this retrospective study, we included 31 patients undergoing unilateral permanent common carotid artery and/or ICA occlusion for carotid blowout syndrome between May 2009 and December 2016. The vascular diameter of the circle of Willis was evaluated using preprocedural CTA, and the risk of borderzone infarction was graded as very high risk, high risk, intermediate risk, low risk, and very low risk. RESULTS: The performance of readers' consensus on CTA for predicting borderzone infarction was excellent, with an area under receiver operating characteristic curve of 0.938 (95% confidence interval, 0.85-1.00). We defined very high risk, high risk, and intermediate risk as positive for borderzone infarction, the sensitivity, specificity, positive predictive value, and negative predictive value of CTA for borderzone infarction were 100% (7/7), 62.5% (15/24), 43.8% (7/16), and 100% (15/15), respectively. The interobserver reliability was excellent (ϭ 0.807). No significant difference in the receiver operating characteristic curves was found between the 2 readers (P ϭ .114). CONCLUSIONS: CTA can be used to predict borderzone infarction after permanent common carotid artery and/or ICA occlusion by measuring the collateral vessels of the circle of Willis. ABBREVIATIONS: AcomA ϭ anterior communicating artery; A z ϭ area under the ROC curve; BTO ϭ balloon test occlusion; CBS ϭ carotid blowout syndrome; CCA ϭ common carotid artery; PCO ϭ permanent common carotid artery and/or ICA occlusion; PcomA ϭ posterior communicating artery; ROC ϭ receiver operating characteristic

Formosan Journal of Musculoskeletal Disorders, Aug 23, 2019

Neurointerventional radiology has many applications in the skull base. We focus on preoperative e... more Neurointerventional radiology has many applications in the skull base. We focus on preoperative embolization to hypervascular tumors and embolization of the vascular lesion, in a hope to keep in-depth discussion. The former section discusses preoperative embolization to hypervascular tumours. The goals of the preoperative embolization are to devascularize the tumour vessel and to decrease surgical blood loss. The basic principle is emphasized in this part. Dangerous intracranial-extracranial collateral, in terms of functional anatomy, is introduced. Embolic agents and embolization methods are comprehensively discussed. Illustrations with the juvenile angiofibroma and paraganglioma are presented. In the section on vascular lesions, we discuss the dural arteriovenous fistula and carotid cavernous fistula. The goal of embolization treatment is usually disease cure or alteration of natural history. The pathophysiology, classification, and clinical presentations of the entities are briefly reviewed. Embolization approaches and common techniques are discussed with updated evidence. Other issues, including postprocedural care and alternative treatments, are also covered in this section.

Formosan Journal of Surgery, 2022

Journal of the Formosan Medical Association, Jul 1, 2022

BACKGROUND AND PURPOSE Carotid blowout syndrome (CBS) is a devastating complication of head and n... more BACKGROUND AND PURPOSE Carotid blowout syndrome (CBS) is a devastating complication of head and neck cancer (HNC). In this study, we describe radiological features that can predict imminent (<6 months) carotid blowout in patients with HNC. METHODS Cross-sectional CT or MRI were interpreted from 25 treated HNC patients with acute CBS and 50 treated HNC patients without CBS (controls). The tumor size and the distance from the tumor to the carotid trunk was measured. The following imaging findings of the tumor were also recorded: carotid trunk involvement, enhancement pattern, and the presence of air-containing necrosis. The odds ratios of imminent CBS for each imaging finding were estimated using a multivariable logistic regression model. RESULTS Compared to the controls, the CBS group had larger tumors (49 ± 18 mm vs. 38 ± 18 mm, p = 0.017), tumors closer to the carotid trunk (0.5 ± 1.7 mm vs. 8.2 ± 14.2 mm, p < 0.001), a higher prevalence of 360° involvement (60% vs. 18%, p < 0.001), more heterogeneous enhancement patterns (84% vs. 50% p < 0.001), and more air-containing necrosis (40% vs. 2% p < 0.001). After multivariable adjustment, the presence of air-containing necrosis remained a significant risk factor for imminent CBS (OR: 20.1, 95% CI: 1.98-204.00; p = 0.011). CONCLUSION The presence of air-containing necrosis is associated with a higher risk of imminent CBS. This characteristic imaging finding should be evaluated in the follow-up CT or MRI of HNC patients for early warning.

Journal of the Neurological Sciences, Jun 1, 2016

To introduce the combination of suction thrombectomy (ST) and balloon maceration (BM) for the man... more To introduce the combination of suction thrombectomy (ST) and balloon maceration (BM) for the management of dural venous sinus thrombosis (DVST). Materials and methods: Ten consecutive patients (average age, 53 ± 15 years; range, 30 to 73 years) with DVST treated by ST after BM were evaluated including location of DVST, imaging presentation, procedural findings, and 3-month modified Rankin scale (mRS). Results: All 10 patients had evidence of venous infarct on MR or CT. In addition, seven patients had intracerebral hemorrhage (ICH), one had subarachnoid hemorrhage (SAH), and one had both ICH and SAH. More than one sinus was involved in nine patients. ST after BM was technically successful in all patients, and angiographic relief of venous congestion and good outcome (3-month mRS 0 or 1) was achieved in eight patients (80%). The average procedural time was 73.5 ± 24.7 min. Two patients who were in coma status had negative outcomes, and one had a known chronic thrombotic segment refractory to treatment. No recurrent thrombosis of recanalized sinus was found on follow-up MR venography in six patients and CT venography in two patients. Conclusion: BM followed by ST is a promising technique for the treatment of acute DVST.

European Journal of Radiology, Nov 1, 2019

To correlate the clinical stage and prognosis of oesophageal squamous cell carcinoma (SCC) using ... more To correlate the clinical stage and prognosis of oesophageal squamous cell carcinoma (SCC) using the imaging biomarkers from integrated positron emission tomography (PET)/magnetic resonance imaging (MRI). Methods: In total, 54 consecutive patients with oesophageal SCC who receive PET/MRI scan were recruited before treatment. The imaging biomarkers used were the mean and minimal apparent diffusion coefficients (ADC mean and ADC min), standardized uptake value (SUV), metabolic tumour volume (MTV), and total lesion glycolysis (TLG) of tumours. The correlation between each imaging biomarker and survival was investigated using the Cox proportional hazards model. Results: ADC mean was negatively correlated with SUV max (r = −0.414, P = 0.025). ADC min was negatively correlated with SUV max (r = −0.423, P = 0.001) and SUV peak (r = −0.402, P = 0.003), and was significantly lower in M1 than in M0 tumours (829.6 vs. 1069.8, P = 0.005). MTV was significantly higher in T3 + (P < 0.001), N1 + (P = 0.014) and TNM stage III + (P < 0.001) tumours. TLG was significantly higher in T3 + (P < 0.001), N1 + (P < 0.001), M1 (P = 0.045) and TNM stage III + (P < 0.001) tumours. The MTV/ ADC min ratio exhibited the highest area under the receiver operating characteristic curve (AUROC) for predicting M1 and advanced TNM stage tumours. Multivariate analysis for progression-free survival (PFS) and overall survival (OS) showed that a larger MTV/ADC min was associated with a shorter PFS and OS (P = 0.024 and 0.046, respectively). Conclusion: The imaging biomarkers in integrated PET/MRI may predict clinical stage and survival in patients with oesophageal SCC. Presently, the role of magnetic resonance imaging (MRI) in

CVIR Endovascular, Oct 22, 2019

Background: Delayed postpancreatectomy hemorrhage (PPH) is a fatal complication caused by arteria... more Background: Delayed postpancreatectomy hemorrhage (PPH) is a fatal complication caused by arterial erosion. This study reports a single-center experience of managing delayed PPH with different endovascular treatment approaches. Methods: We reviewed the data of patients who had delayed PPH due to hepatic artery or gastroduodenal artery stump perforation and underwent endovascular treatment between 2003 and 2018. We categorized endovascular treatment approaches involving hepatic artery sacrifice, superselective pseudoaneurysm embolization with hepatic artery preservation, and covered stent placement. Technical success rates, hemorrhage recurrence rates, major and minor hepatic complication rates, and 30-day and 1-year mortality rates were assessed. Results: A total of 18 patients were reviewed; 11 (61%), 4 (22%), and 3 (17%) delayed PPH cases were managed through hepatic artery sacrifice, superselective pseudoaneurysm embolization, and hepatic artery stenting, respectively. Multidetector computed tomography was performed in 14 (78%) patients. The technical success rate was 100%. The overall hemorrhage recurrence rate was 39%, with superselective pseudoaneurysm embolization having a 100% hemorrhage recurrence rate-much higher than that of hepatic artery sacrifice or stent graft placement. The overall major and minor hepatic complication rates were 56% and 83%, respectively. The overall 30day and 1-year mortality rates were 11% and 25%, respectively. The 30-day and 1-year mortality rates and minor and major hepatic complication rates were similar in each group. Conclusion: Hepatic artery sacrifice is more effective than superselective pseudoaneurysm embolization in the management of delayed PPH. Covered stent placement may be a reasonable alternative treatment to hepatic artery sacrifice.

Journal of NeuroInterventional Surgery, May 15, 2020

Cerebral hyperperfusion syndrome (CHS) is a clinical syndrome following a revascularization proce... more Cerebral hyperperfusion syndrome (CHS) is a clinical syndrome following a revascularization procedure. in the past decade, neurointerventional surgery has become a standard procedure to treat stenotic or occluded cerebral vessels in both acute and chronic settings, as well as endovascular thrombectomy in acute ischemic stroke. This review aims to summarize relevant recent studies regarding the epidemiology, diagnosis, and management of CHS as well as to highlight areas of uncertainty. extracranial and intracranial cerebrovascular diseases in acute and chronic conditions are considered. The definition and diagnostic criteria of CHS are diverse. Although impaired cerebrovascular autoregulation plays a major role in the pathophysiology of CHS, the underlying mechanism is still not fully understood. its clinical characteristics vary in different patients. The current findings on clinical and radiological presentation, pathophysiology, incidence, and risk factors are based predominantly on carotid angioplasty and stenting studies. Hemodynamic assessment using imaging modalities is the main form of diagnosis although the criteria are distinct, but it is helpful for patient selection before an elective revascularization procedure is conducted. After endovascular thrombectomy, a diagnosis of CHS is even more complex, and physicians should consider concomitant reperfusion injury. Management and preventative measures, including intensive blood pressure control before, during, and after revascularization procedures and staged angioplasty, are discussed in detail. InTRoduCTIon Cerebral hyperperfusion syndrome (CHS) is a rare but severe complication, and was first described as a clinical syndrome following carotid endarterectomy (CEA). In neurointerventional surgery, CHS may complicate extracranial carotid angioplasty and stenting (CAS), and is characterized by headaches, neurological deficits, and seizures not caused by cerebral ischemia. It is commonly associated with an increase in blood pressure. The incidence and risk factors of CHS have recently been reported in several large cohorts of patients undergoing CAS, intracranial angioplasty and stenting (INCS), and endovascular thrombectomy (EVT). Greater familiarity with recent reports of the clinical symptoms, imaging features, and management strategies for CHS may improve the vigilance necessary for effective diagnosis and prevention. This review focuses on recent important studies on the presentation, diagnosis, pathophysiology, incidence, risk factors, prevention, and management of CHS in patients undergoing CAS, INCS, and EVT. Contributors All authors made substantial contributions to the conception and design of the study; acquisition of data or analysis and interpretation of the data; drafting the article or revising it critically for important intellectual content; and final approval of the manuscript.

Stroke, Jan 22, 2018

Permanent common and/or internal carotid artery occlusion (PCO) is an effective treatment for car... more Permanent common and/or internal carotid artery occlusion (PCO) is an effective treatment for carotid blowout syndrome (CBS). However, PCO may cause stroke, especially border zone infarction, when the collateral flow to the deprived brain territory is insufficient. In this study, we aimed to test the predictive value of collateral reserve on computed tomography angiography (CTA) for assessing post-PCO stroke risk in patients with CBS. In this retrospective institutional review board–approved study, we included 31 patients receiving unilateral PCO for CBS between May 2009 and December 2016. Two neuroradiologists evaluated all preprocedural CTA to determine the collateral reserve of the circle of Willis. The risk of post-PCO stroke was graded into very high risk, high risk, intermediate risk, low risk, and no risk, and were subjected to receiver operating characteristic curve analysis. Defining the very high risk and high risk groups as positive, the performance of reader’s consensus on CTA for predicting border zone infarction was excellent, with an area under receiver operating characteristics curve of 0.938 (95% confidence interval: 0.85–1.00). The overall sensitivity, specificity, positive predictive value, and negative predictive value was 85.7%, 87.5%, 66.7%, and 95.5%, respectively. The interobserver reliability was excellent (κ = 0.807). No significant difference in the receiver operating characteristics curves were found between the two readers (P = 0.114). In conclusion, CTA can be used to predict border zone infarction after PCO by measuring the collateral reserve of the circle of Willis.

American Journal of Neuroradiology, Apr 4, 2019

BACKGROUND AND PURPOSE: Spine debulking surgery in patients with hypervascular spinal metastasis ... more BACKGROUND AND PURPOSE: Spine debulking surgery in patients with hypervascular spinal metastasis is associated with massive intraoperative blood loss, but currently, the vascularity of tumor is determined by invasive conventional angiography or dynamic contrast MR imaging. We aimed to investigate the usefulness of noninvasive dual-energy CT-DSA, comparing it with conventional angiography in evaluating the vascularity of spinal metastasis. MATERIALS AND METHODS: We conducted a retrospective study from January to December 2018. A total of 15 patients with spinal metastasis undergoing dual-energy CT, conventional DSA, and subsequent debulking surgery were included. CT-DSA images were produced after rigid-body registration and subtraction between CT phases. Qualitative and quantitative assessments of tumor vascularity were conducted. Correlations between CT-DSA and conventional DSA results were evaluated using the Spearman coefficient. The mean enhancement in the estimated tumor volume and surgical blood loss was compared between hypervascular and nonhypervascular groups using the Wilcoxon rank sum test. RESULTS: The CT-DSA and DSA results were strongly correlated, with ϭ 0.87 (P Ͻ .001). The DSA and the quantitative enhancement index also showed a strong correlation with ϭ 0.83 (P Ͻ .001). Wilcoxon rank sum testing between hypervascular and nonhypervascular CT-DSA groups showed a difference in enhancement indices (P ϭ .0003). The blood loss between the hypervascular and nonhypervascular groups was nonsignificant (P ϭ .09). CONCLUSIONS: Dual-energy CT-DSA correlates well with conventional DSA in assessing the vascularity of spinal metastasis. It may serve as a noninvasive preoperative evaluation option before debulking surgery.

American Journal of Neuroradiology, Jan 17, 2019

BACKGROUND AND PURPOSE: Simple-but-precise evaluation of cerebral perfusion is crucial for the tr... more BACKGROUND AND PURPOSE: Simple-but-precise evaluation of cerebral perfusion is crucial for the treatment of Moyamoya disease. We aimed to develop a standardized scoring system for MR perfusion suitable for Moyamoya disease evaluation and investigate the postoperative serial changes and outcome predictors. MATERIALS AND METHODS: From January 2013 to December 2016, patients diagnosed with Moyamoya disease and receiving indirect revascularization were recruited prospectively. Clinical data and serial imaging studies were analyzed. The TTP maps were standardized using cerebellar reference values. We developed a scoring system of standardized TTP maps: 14 points for each hemisphere with higher points indicating better perfusion. RESULTS: In total, 24 children (4-17 years of age, 41 hemispheres) and 20 adults (18-51 years of age, 34 hemispheres) were included. The mean preoperative TTP scores were higher in children (7.34 Ϯ 3.90) than in adults (4.88 Ϯ 3.24). The standardized TTP maps revealed dynamic improvement with an increase in the corresponding scores at the 1-, 3-, and 6-month postoperative follow-ups; the scores stabilized after 6 months. The mean improvement in the 6-month scores of the pediatric and adult groups was 4.15 Ϯ 3.55 and 6.03 Ϯ 3.04, respectively. The 6-month TTP score improvements were associated with Matsushima grades. If we took score improvement as the outcome, the preoperative TTP score was the only significant predictor in multivariable analysis. CONCLUSIONS: The standardized TTP maps and scoring system facilitated the quantification of the sequential perfusion changes during Moyamoya disease treatment. The preoperative perfusion status was the only predictor of indirect revascularization outcome. ABBREVIATIONS: EDAS ϭ encephaloduroarteriosynangiosis; EPS ϭ encephalopericraniosynangiosis; MMD ϭ Moyamoya disease; MRP ϭ MR perfusion M oyamoya disease (MMD) is a progressive occlusive disease

European Radiology, Nov 30, 2022

Owing to NAND flash technology facing its scaling limit, resistive random access memory (RRAM) wi... more Owing to NAND flash technology facing its scaling limit, resistive random access memory (RRAM) with simple film stack and no cross coupling issue between cells is a promising candidate for future high density memory application [1,2]. The 1TnR architecture with 3D vertical RRAM (VRRAM) structure realizes ultra-low bit cost for high compact density array [3,4]. However, this novel 1TnR structure and processes have not been proved yet. To meet requirements of VRRAM array operation, the nonlinear resistive memory with an excellent self-compliance and low current operation is indispensable [5,6]. A large voltage margin for the device operated with compliance current (ΔVCOMP) and high nonlinearity for the device at low resistance state (LRS) with reliable read voltage should be addressed.

Neuroradiology, Nov 30, 2017

Purpose Computed tomography angiography (CTA) and magnetic resonance imaging/angiography (MRI/MRA... more Purpose Computed tomography angiography (CTA) and magnetic resonance imaging/angiography (MRI/MRA) are used for the diagnosis of intracranial dural arteriovenous fistulas (DAVFs). The purpose of this study was to compare the diagnostic accuracy of CTA and magnetic resonance imaging/angiography (MRI/MRA) for detection of cortical venous reflux (CVR) in intracranial DAVFs. Methods The records of patients with angiography-confirmed intracranial DAVFs who also received CTA and MRI/MRA from January 2008 to July 2016 were reviewed. CTA and MRI/MRA were reviewed for signs of CVR, and the diagnostic accuracy of individual signs was evaluated by receiver operating curve (ROC) analysis. Results A total 108 patients were included in this study. CTA signs of CVR included abnormal dilatation, early enhancement, and the presence of a medullary or pial vein. MRI/MRA signs of CVR included abnormal dilatation, early enhancement, flow-related enhancement, flow void, and medullary or pial venous collaterals. The sensitivity of individual CTA signs ranged from 62 to 96%, and specificities from 79 to 94%. The sensitivities of individual MRI/MRA signs ranged from 58 to 83%, and specificities from 77 to 93%. The area under ROC curve (AUC) of CTA and MRI/MRA were 0.91 and 0.87, respectively (P = 0.04 in direct comparison). In subgroup analysis, CTA had better diagnostic accuracy for higher grade disease (P = 0.05) and non-aggressive manifestation (P = 0.04). Conclusions Both CTA and MRI/MRA have good diagnostic accuracy for detection of CVR in patients with intracranial DAVFs. There is modest evidence that CTA is better than MRI/MRA.