• Journal of Korean Neurosurgical Society
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• v.60 no.3
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• pp.335-347
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• 2017

Intravenous recombinant tissue plasminogen activator had been the only approved treatment for acute ischemic stroke since its approval in 1995. However, the restrictive time window, numerous contraindications, and its low recanalization rate were all limitations of this modality. Under those circumstances, endovascular stroke therapy went through a great evolution during the past two decades of intravenous thrombolysis. The results of the 2013 randomized trials for endovascular stroke therapy were neutral, although they were limited by insufficient imaging screening at enrollment, early-generation devices with less efficacy, and treatment delays. Huge progress was made in 2015, as there were five randomized clinical trials which all demonstrated the safety and efficacy of endovascular stroke treatment. Despite differences in detail patient enrollment criteria, all 5 trials employed key factors for good functional recovery; (1) screening with non-invasive imaging to identify the proximal occlusion and exclude a large infarct core, (2) using highly effective modern thrombectomy devices mainly with stent retriever, and (3) establishment of a fast workflow to achieve effective reperfusion. The results of those trials indicate that modern thrombectomy devices can allow for faster and more effective reperfusion, which can lead to improved clinical outcomes compared to intravenous thrombolysis alone. These advances in mechanical thrombectomy are promising in the global fight against ischemic stroke-related disability and mortality. Two current mainstreams among such mechanical thrombectomy techniques, "stent retriever thrombectomy" and "direct clot aspiration", are the topic of this review. Stent retriever thrombectomy using Solitaire and Trevo retriever will be firstly discussed. And, the commonalities and the differences between two major clot aspiration thrombectomy techniques; a direct aspiration first pass technique (ADAPT) and forced arterial suction thrombectomy (FAST), will be additionally explained. Finally, details regarding the combination of direct clot aspiration and stent retriever thrombectomy, the switching strategy and the Solumbra technique, will be described.

• Journal of Veterinary Clinics
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• v.20 no.1
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• pp.104-109
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• 2003

This study was performed to evaluate the postoperative heating process according to lameness degree, swelling, and muscle atrophy after femoral head and neck ostectomy on Retriever dogs with hip dysplasia and hindleg lameness. Femoral head and neck ostectomy (FHO) was performed for the repair of hip dysplasia in 4 Retriever dogs (5 hips) referred in veterinary medical teaching hospital of college of veterinary medicine, Konkuk University. Age (Mean $\pm$ SD) of patients was 10.3 $\pm$ 3.0 months (range,7 to 16 months) and body weight (Mean $\pm$ SD) was 28.2 $\pm$ 3.4 kg (range, 25 to 34 kg). After FHO, all cases are treated with carprofen (2.2 mg/kg, PO bid, tapering at interval 1-2 weeks) and physical therapy including passive range-of-motion exercises. In all cases, lameness degree was showed V at the next day after surgery, IV at 5 to 7 days, II-III at 30 to 35 days, II at 60 days, and I at 105 to 114 days. These results suggested that femoral head and neck ostectomy was able to be performed on large breed dogs with hip dysplasia and hindleg lameness.

• Journal of Korean Neurosurgical Society
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• v.65 no.4
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• pp.514-522
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• 2022

Objective : A distal navigation of a large bore aspiration catheter during mechanical thrombectomy (MT) is important. However, delivering a large bore aspiration catheter is difficult to a tortuous or atherosclerotic artery. We report the experience of anchoring with balloon guide catheter (BGC) and stent retriever to facilitate the passage of an aspiration catheter in MT. Methods : When navigating an aspiration catheter failed with a conventional co-axial microcatheter delivery, an anchoring technique was used. Two types of anchoring technique were applied to facilitate distal navigation of a large bore aspiration catheter during MT. First, a passage of aspiration catheter was attempted with a proximal BGC anchoring technique. If this technique also failed, another anchoring technique with distal stent retriever was tried. Consecutive patients who underwent MT with an anchoring technique were identified. Details of procedure, radiologic outcomes, and safety variables were evaluated. Results : A total of 67 patients underwent MT with an anchoring technique. Initial trial of aspiration catheter passage with proximal BGC anchoring technique was successful for 35 patients (52.2%) and the second trial with distal stent retriever anchoring was successful for 32 patients (47.8%). Overall, navigation of a large bore aspiration catheter was successful for all patients (100%) without any procedure related complications. Conclusion : Our study showed the usefulness of anchoring technique with proximal BGC and distal stent retriever during MT, especially in those with an unfavorable anatomical structure. This technique could be an alternative option for delivering an of aspiration catheter to a distal location.

• Annual Conference on Human and Language Technology
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• 2022.10a
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• pp.131-134
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• 2022

자연어처리 분야 중 질의응답 태스크는 전통적으로 많은 연구가 이뤄지고 있는 분야이며, 최근 밀집 벡터를 사용한 리트리버(Dense Retriever)가 성공함에 따라 위키피디아와 같은 방대한 정보를 활용하여 답변하는 오픈 도메인 QA(Open-domain Question Answering) 연구가 활발하게 진행되고 있다. 대표적인 검색 모델인 DPR(Dense Passage Retriever)은 바이 인코더(Bi-encoder) 구조의 리트리버로서, BERT 모델 기반의 질의 인코더(Query Encoder) 및 문단 인코더(Passage Encoder)를 통해 임베딩한 벡터 간의 유사도를 비교하여 문서를 검색한다. 하지만, BERT와 같이 엔티티(Entity) 정보에 대해 추가적인 학습을 하지 않은 언어모델을 기반으로 한 리트리버는 엔티티 정보가 중요한 질문에 대한 답변 성능이 저조하다. 본 논문에서는 엔티티 중심의 질문에 대한 답변 성능 향상을 위해, 엔티티를 잘 이해할 수 있는 LUKE 모델 기반의 리트리버를 제안한다. KorQuAD 1.0 데이터셋을 활용하여 한국어 리트리버의 학습 데이터셋을 구축하고, 모델별 리트리버의 검색 성능을 비교하여 제안하는 방법의 성능 향상을 입증한다.

• Journal of Korean Neurosurgical Society
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• v.64 no.1
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• pp.30-38
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• 2021

Objective : The Solitaire Platinum 4×40 mm stent retriever contains radiopaque markers with a long length. We evaluated the effect of Solitaire Platinum 4×40 mm stent retriever in Solumbra technique thrombectomy, and compared it with shorter Solitaire stent retrievers. Methods : A total of 70 patients who underwent Solumbra technique thrombectomy with equal diameter (4 mm) and different length (40 vs. 20 mm) Solitaire stent retrievers were divided into two groups : the Solitaire Platinum 4×40 mm stent (4×40) group and the Solitaire FR 4×20 mm stent or Solitaire Platinum 4×20 mm stent (4×20) group. The clinical outcomes, Thrombolysis in Cerebral Infarction score, the first pass reperfusion status, and complications were evaluated and compared between the two groups. Multivariate analysis was performed to evaluate the predictive factors for reperfusion and complete reperfusion from the first pass. Results : Higher first-pass reperfusion and complete reperfusion were achieved in the 4×40 group (68.0% and 48.0%) than in the 4×20 group (46.7% and 33.3%; p=0.004 and 0.007, respectively). In multivariate analysis, radiopaque device and longer stent retriever were correlated with first-pass reperfusion (p=0.014 and 0.008, respectively) and first-pass complete reperfusion (p=0.022 and 0.012, respectively). Conclusion : Our study demonstrated the usefulness of the Solitaire Platinum 4×40 mm stent retriever, which led to higher first-pass reperfusion and complete reperfusion rates than the Solitaire FR 4×20 mm stent or the Solitaire Platinum 4×20 mm stent, especially in Solumbra technique thrombectomy.

• Korean Journal of Veterinary Service
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• v.30 no.4
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• pp.539-544
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• 2007

A 7-year-old intact female Golden Retriever was presented for examination. The dog had large irregular subcutaneous masses in the abdomen which were ruptured or encapsulated. Those were removed surgically. Histopathologically, the masses consisted of spindle cells that often formed distinct whorls around a central capillary. Immuno-histochemical analysis revealed that the neoplastic cells were strong diffuse cyto-plasmic immunolabelling for vimentin and focal immunoreactivity for smooth muscle actin, whereas not immunoreactive for cytokeratin, desmin, von Willebrand factor, glial fibrillary acidic protein, or S-100. The neoplastic cells ultrastructurally had processes attached by desmosome-like structures, swollen mitochondria and dilated rough endoplasmic reticulum. Based on the above results, this case was diagnosed as a canine hemangiopericytoma in the abdominal subcutis of a Golden Retriever.

• Journal of Veterinary Clinics
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• v.33 no.1
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• pp.62-64
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• 2016

A 6 months old, 20.5 kg female Golden Retriever dog was presented with bilateral exophthalmos and no protrusion of the third eyelid. Based on the patient's history, clinical signs, physical examination and ophthalmologic examination, extraocular myositis (EOM) was diagnosed. The exophthalmos was reduced after 7 days and disappeared after 14 days of corticosteroids treatment. Discontinuation of corticosteroids treatment can lead to recurrence of EOM, but in this case there was no recurrence for 2 months. This is the first reported case of canine extraocular myositis in Korea.

• Journal of Korean Neurosurgical Society
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• v.57 no.5
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• pp.342-349
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• 2015

Background : Higher reperfusion rates have been established with endovascular treatment for acute ischemic stroke patients. There are limited data on the comparative performance of mechanical thrombectomy devices. This study aimed to analyse the efficacy and safety of the stent retriever device (Solitaire stent) by comparing procedure time, angiographic outcome, complication rate and long term clinical outcome with previous chemical thrombolysis and mechanical thrombectomy using penumbra system. Method : A retrospective single-center analysis was undertaken of all consecutive patients who underwent chemical thrombolysis and mechanical thrombectomy using Penumbra or Solitaire stent retriever from March 2009 to March 2014. Baseline characteristics, rate of successful recanalization (modified Thrombolysis in Cerebral Infarction score 2b-3), symptomatic intracerebral hemorrhage, procedure time, mortality and independent functional outcomes ($mRS{\leq}2$) at 3 month were compared across the three method. Results : Our cohort included 164 patients, mechanical thrombectomy using stent retriever device had a significant impact on recanalization rate and functional independence at 3 months. In unadjusted analysis mechanical thrombectomy using Solitaire stent retriever showed higher recanalization rate than Penumbra system and chemical thrombolysis (75% vs. 64.2% vs. 49.4%, p=0.03) and higher rate of functional independence at 3 month (53.1% vs. 37.7% vs. 35.4%, p=0.213). In view of the interrelationships between all predictors of variables associated with a good clinical outcome, when the chemical thrombolysis was used as a reference, in multiple logistic regression analysis, the use of Solitaire stent retriever showed higher odds of independent functional outcome [odds ratio (OR) 2.62, 95% confidence interval (CI) 0.96-7.17; p=0.061] in comparison with penumbra system (OR 1.57, 95% CI 0.63-3.90; p=0.331). Conclusion : Our initial data suggest that mechanical thrombectomy using stent retriever is superior to the mechanical thrombectomy using penumbra system and conventional chemical thrombolysis in achieving higher rates of reperfusion and better outcomes. Randomized clinical trials are needed to establish the actual benefit to specific patient populations.

• Journal of Life Science
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• v.13 no.4
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• pp.416-420
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• 2003

We performed this study to determine the parentage verification of putative dogs. A total of 7 samples (4 Labrador Retriever dog and 3 Poongsan dog) were genotyped by using 12 international markers (PEZ1, PEZ5, PEZ8, PEZ10, PEZ11, PEZ12, PEZ17, PEZ20, PEZ21, FHC2010, FHC2054, FHC2079). This methods consisted of multiplexing PCR procedures, and it showed reasonable amplification of all PCR products. Genotyping was performed with an ABI 310 genetic analyzer. Labrador Retriever Pup I and Pup II were included according to principles of Mendelian genetics in all loci, while Poongsan Pup III was excluded with markers PEZ1 (106/118), PEZ10 (276/300), and FHC2010 (228/232). These results suggest that the present DNA typing is so useful for parentage verification of these two breeds.

• Korean Journal of Veterinary Research
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• v.60 no.4
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• pp.233-236
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• 2020

A five-year-old spayed female Labrador retriever presented with right forelimb lameness one day earlier. Radiographs and computed tomography of the right shoulder joint revealed conspicuous enthesophytes, bone cyst, and bone fragment at the intertubercular groove. Magnetic resonance imaging showed a loss of continuity of the biceps tendon and inhomogeneous hyperintense signal of the surrounding soft tissue and moderate synovial fluid on T2- and proton density-weighted images with contrast enhancement on the postcontrast T1-weighted images. The dog was diagnosed with tenosynovitis and biceps tendon rupture with osteoarthritis based on a comprehensive evaluation of the computed tomography and magnetic resonance imaging features.