Dae Sik Ryu
University of Ulsan
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Featured researches published by Dae Sik Ryu.
Journal of Vascular and Interventional Radiology | 2002
Deok Hee Lee; Kwang Deog Jo; Hyeon Gak Kim; Soo-Jung Choi; Seung Mun Jung; Dae Sik Ryu; Man Soo Park
PURPOSE One of the most important prognostic factors in the thrombolytic treatment of acute ischemic stroke is the time to recanalization. To shorten the recanalization time, an antiplatelet agent, abciximab (platelet glycoprotein receptor IIb/IIIa antagonist), was administered intravenously before the initiation of local intraarterial urokinase thrombolysis. The purpose of this study was to evaluate the effectiveness and safety of this combined therapy. MATERIALS AND METHODS A total of 26 patients with acute ischemic stroke (National Institutes of Health Stroke Scale score >10) were enrolled in this study. In the earlier phase of this study, conventional local intraarterial urokinase thrombolysis was performed in 16 patients (urokinase group). In the later phase, combined use of intravenous abciximab and local intraarterial urokinase thrombolysis was performed in 10 patients (urokinase + abciximab group). Recanalization rate (Thrombolysis in Myocardial Infarction grade >or=2), total amount of urokinase used, incidence of symptomatic hemorrhage, and better functional outcome rate (modified Rankin scale <or=2) were compared between the two groups with use of the Fisher exact test or Mann-Whitney U test. RESULTS The recanalization rate in the urokinase + abciximab group (90%, nine of 10) was significantly higher than that in the urokinase group (43.8%, seven of 16) (P =.037). The mean amount of urokinase required for recanalization was significantly lower in the urokinase + abciximab group (828,000 IU vs 418,000 IU; P <.005). As for the incidence of symptomatic hemorrhage, no significant difference was noted between the two groups (four of 16 vs three of 10) (P = 1.0). The urokinase + abciximab group showed a trend of better functional outcome (50% vs 80%; P =.2). CONCLUSIONS Combined therapy employing intravenous abciximab and local intraarterial urokinase thrombolysis showed a marked improvement in recanalization rate and showed a trend of better functional outcome. The safety of this regimen still remains to be justified with modification of the indication and regimen dosage.
Korean Journal of Radiology | 2007
Soo Jung Choi; Jae Seok Song; Chunghwan Kim; Dae Sik Ryu; Jae Hong Ahn; Seung Moon Jung; Man Soo Park
Objective We wanted to investigate the relationship between the magnetic resonance (MR) findings and the clinical outcome after treatment with non-surgical transforaminal epidural steroid injections (ESI) for lumbar herniated intervertebral disc (HIVD) patients. Materials and Methods Transforaminal ESI were performed in 91 patients (50 males and 41 females, age range: 13-78 yrs) because of lumbosacral HIVD from March 2001 to August 2002. Sixty eight patients whose MRIs and clinical follow-ups were available were included in this study. The medical charts were retrospectively reviewed and the patients were divided into two groups; the successful (responders, n = 41) and unsatisfactory (non-responders, n = 27) outcome groups. A successful outcome required a patient satisfaction score greater than two and a pain reduction score greater than 50%. The MR findings were retrospectively analyzed and compared between the two groups with regard to the type (protrusion, extrusion or sequestration), hydration (the T2 signal intensity), location (central, right/left central, subarticular, foraminal or extraforaminal), and size (volume) of the HIVD, the grade of nerve root compression (grade 1 abutment, 2 displacement and 3 entrapment), and an association with spinal stenosis. Results There was no significant difference between the responders and non-responders in terms of the type, hydration and size of the HIVD, or an association with spinal stenosis (p> 0.05). However, the location of the HIVD and the grade of nerve root compression were different between the two groups (p< 0.05). Conclusion MRI could play an important role in predicting the clinical outcome of non-surgical transforaminal ESI treatment for patients with lumbar HIVD.
Radiology | 2011
Soo-Jung Choi; Jae Hong Ahn; Young-Jun Lee; Dae Sik Ryu; Jong Hyeog Lee; Seung Moon Jung; Man Soo Park; Ki-Won Lee
PURPOSE To demonstrate the usefulness of ultrasonography (US) in the detection of anatomic variations in the first extensor compartment of the wrist in patients with de Quervain disease. MATERIALS AND METHODS The institutional review board approved this study protocol and waived the informed consent requirement. Fifteen wrists in 13 women (age range, 41-62 years) in whom de Quervain disease was clinically diagnosed and who underwent surgery for intractable pain were included. A musculoskeletal radiologist performed US before surgery. The absence or presence and extent of subcompartmentalization within the first extensor compartment and the number of abductor pollicis longus (APL) and extensor pollicis brevis (EPB) tendon slips were evaluated and recorded. Preoperative US findings were compared with surgical records and photographs. RESULTS Subcompartmentalization within the first extensor compartment was observed during surgery in 11 of the 15 wrists (73%), including four (27%) that had subcompartmentalization only in the distal portion of this compartment. US was used to identify all 11 wrists showing subcompartmentalization within this compartment (sensitivity, 100%; 95% confidence interval [CI]: 74%, 100%), as well as three of the four wrists with distal incomplete subcompartmentalization. There was one wrist with false-positive distal incomplete subcompartmentalization. US had a positive predictive value in the detection of subcompartmentalization of 73% (95% CI: 47%, 91%). The number of tendon slips in this compartment detected with US was identical to that identified at surgery with one exception. CONCLUSION US can be used to depict various types of anatomic variations in the first extensor compartment in patients with de Quervain disease.
Korean Journal of Radiology | 2008
Soo-Jung Choi; Jae Hong Ahn; Gil-Hyun Kang; Jong Hyeog Lee; Man Soo Park; Dae Sik Ryu; Seung Moon Jung
Calcifying aponeurotic fibroma is a rare soft tissue tumor that occurs in the distal extremities of children and adolescents. We report ultrasound and X-ray findings of a calcifying aponeurotic fibroma in the finger of a 36-year-old woman, associated with distal phalangeal bone involvement.
Korean Journal of Radiology | 2001
Deok Hee Lee; Seung Ho Hur; Hyeon Gak Kim; Seung Mun Jung; Dae Sik Ryu; Man Soo Park
Extracranial carotid artery dissection may manifest as arterial stenosis or occlusion, or as dissecting aneurysm formation. Anticoagulation and/or antiplatelet therapy is the first-line treatment, but because it is effective and less invasive than other procedures, endovascular treatment of carotid artery dissection has recently attracted interest. We encountered two consecutive cases of trauma-related extracranial internal carotid artery dissection, one in the suprabulbar portion and one in the subpetrosal portion. We managed the patient with suprabulbar dissection using a self-expandable metallic stent and managed the patient with subpetrosal dissection using a balloon-expandable metallic stent. In both patients the dissecting aneurysm disappeared, and at follow-up improved luminal patency was observed.
Journal of the Korean Radiological Society | 2006
Soo Youn Park; Man Soo Park; Heon Han; Ji Yeon Lee; Yong Hwan Jeon; Seung Mun Jung; Nam Hyun Kim; Seong Eon Yoon; Mi Kyeong Oh; Hang Seob Jung; Dae Sik Ryu
Purpose: The purpose of this study was to investigate the usefulness of the ultrasonography as a screening test for thyroid diseases. Materials and Methods: For 7 months, thyroid ultrasonography (7.5 MHz linear array) was performed prospectively by radiologists on 1,316 subjects who do not have a history of the thyroid disease. We analyzed the morphological abnormalities of thyroid gland and these were classified as the nodulal, cystic and diffuse types in accordance with the gender and ages of the patients. We performed ultrasound-guided fine needle aspiration in 21 patients who had sonographic features that were suggestive of malignant thyroid nodules. Physical examination was performed for all subjects by clinicians before the thyroid ultrasonography, and we compared the detectability of thyroid lesions between ultrasonography and physical examination. Results: Thyroidal abnormalities were detected in 94 (7.1%) of 1,316 subjects. Among the 94 patients, 72 (5.5%) showed as nodules, 18 (1.4%) showed as cysts and 4 (0.3%) showed as diffuse abnormalities. The result of the ultrasound-guided aspiration on 21 patient showed 4 malignant nodules, 16 benign nodules and 1 undetermined nodule. Physical examination detected abnormalities in only 12 patients (12.8%) of the 94 patients, which were showed as nodules, cysts and the diffuse type by ultrasonography. Conclusion: Thyroid disease of the general population was relatively common and the detection rate with performing physical examination for the thyroid nodule, cyst and the diffuse type was lower than that for ultrasonography. Thyroid ultrasonography is a useful screening modality for detecting thyroid diseases.
Tuberculosis and Respiratory Diseases | 2001
Sung Oh Park; Hyuk Ko; Su Hee Kim; Wan Park; Deck Hee Lee; Dae Sik Ryu; Bock Hyun Jung
A 42 year-old male with a history of multidrug-resistant pulmonary tuberculosis suddenly developed massive hemoptysis. Embolization of a bronchial artery branch and the collateral systemic arteries did not resolve the recurrent bleeding. Spiral computerized tomography(spiral CT) of the chest showed contrast enhanced nodules within a large cavity at the left lower lobe in the arterial phase suggesting a Rasmussen aneurysm. A pulmonary angiogram showed abnormal vascular nodules at that site. Coils were deployed at both the proximal and distal vessels of this aneurysmal sac for embolization. Transcatheter arterial embolization is a safe and effective means of controlling bleeding from this pulmonary arterial pseudoaneurysm. Here we report a case of a Rasmussen aneurysm diagnosed by spiral CT, which was successfully treated by pulmonary arterial embolization with a coil.
Journal of Clinical Radiololgy | 2000
Dae Sik Ryu; Kun Sang Kim; Kil Hyen Kang; Haing Sup Chung; Bung Wok Lee; Young Ki Kim; Tae Keun Lee; Nam Hyeon Kim; Seung Mun Jung; Man Soo Park
Purpose : To evaluate imaging findings and lung density changes after 95% oxygen inhalation in rat. Materials and Methods : A total of 18 rats were divided into three groups on the basis of inhalation time: group I(n=6) inhaled 95 % oxygen for 24 hours, and group II(n=6) for 48 hours, group III(n=6) for 60 hours. A control group(n=6) inhaled room air(21 % oxygen). Chest radiograph and high resolution computed tomography were performed, and pathologic and imaging findings were compared. Results : Chest radiograph showed abnormality only in group III. High resolution CT, however, revealed abnormal findings in all three groups : diffuse ground glass opacity in groups I, II and III, additional focal patchy consolidation at the peripheral portion in group II, and diffuse consolidation in group III. Lung density was sig-nificantly higher in group I than in controls(p 0.05). In group III, density was significantly higher than in group II. The lung density changes seen in all groups showed a bilateral diffuse increased pattern. but, in group III, changes were more severe in the central, peripheral and posterior portion of the lower lung. Ground glass opacity and focal patchy consolidaton seen on HRCT were found on pathologic examination to be due to alveolar cell hyperplasia and septal thickening. Consolidation was caused by alveolar edema and hemorrage. Pathologic lesions were randomly distributed in both lungs. Conclusion : One HRCT images, rat exposed to hyperoxia showed ground glass opacity, patchy consolidation and diffuse consolidation. Depending on exposure time, the pathologic findings also indicated increased lung density and a bilateral, diffuse distribution pattern, as well as alveolar cell hyperplasia and septal thickening, alveolar edema and hemorrage. HRCT may be more helpful than simple X-rays for the early detection of pulmonary oxygen toxicity.
Journal of Clinical Radiololgy | 1999
Seung Mun Jung; Nam Hyeun Kim; Dae Sik Ryu; Jong Yeon Park; Han Gwun Kim; Man Soo Park
Purpose : To evaluate the usefulness of MR urography(MRU) using Half-Fourier acquisition single-shot turbospin-echo(HASTE) sequence compared with conventional intravenous urography(IVU). Materials and Methods : Thirtyfive lesions of 32 patients who underwent MRU because of delayed excretion or nonvisualization of the ureter wereincluded in this study. HASTE MR urography was performed with a 1.0 MR imaging unit. Coronal images includingthose of the kidney, ureter and bladder were obtained in every pa-tient using the multislice technique, and werepostprocessed by means of the maximal intensity projection technique. Scan time was 17-19 seconds. We analyzed theresults of MRU, focusing on level of obstruction, in-cidence of stone, ureter dilatation, and motion artifact, andin each case compared MRU findings with those of IVU. Results : In 12 of 35 lesions(34.2%), MRU more effectivelydiagnosed causes of obstruction than did IVU, while in seven lesions(20%), MRU and IVU were similar. In eightlesions(22.9%), all of which were caused by a stone, IVU was better than MRU, and in a further eight, neithermodality was able to diagnose the cause. For diagnosis of the level of obstruction, MRU was better than IVU in 20of 35 lesions(57.1%), and similar to IVU in seven(20%). In three lesions(8.6%), neither modality was able todetect the level of obstruction. Four lesions not related to obstruction were polycystic renal disease, cysticrenal change, vesicovaginal fistula and extra-re-nal pelvis. Dilatation of the ureter was seen in 23lesions(65.8%) on MRU and in seven lesions on IVU. Thus, MRU revealed dilatation of for the ureter more efectivelythan IVU. Conclusion : MRU using HASTE was valuable for the detection of underlying causes and levels ofobstruction in the urinary tract, and of abnormalities in surrounding structures in patients withnon-visualization of the kidney or delayed contrast excretion of the ureter, as seen on delayed IVU urogram.
Journal of Clinical Radiololgy | 1999
Nam Hyeon Kim; Seung Mun Jung; Dae Sik Ryu; Man Soo Park
Purpose : To evaluate the efficacy of a newly designed cassette and film system used to obtain a craniocaudal(CC) image during mammographic examination. Materials and Methods : We designed a film-cassette system for use inobtaining a CC image. The merit of this system is that the contact plane between the film and film cassette andthe thoracic wall of the examinee changed from linear to concave, thus including more tissue on the image. Twentywomen examined by screening mammography underwent conventional and new CC plane examinations. The distance fromthe nipple to the posterior margin of the included breast tissue, as seen on CC mammograms, was measured using thetwo techniques, and the difference between the respective results was analyzed by paired t-test. Results : Thedistance from the nipple to the posterior margin was at the lateral portion of theconventional and new CC image, respectively. This distance was thus significantly greater on the new than on theconventional image (p