• Journal of the Korean Society of Radiology
• /
• v.14 no.5
• /
• pp.619-626
• /
• 2020

This study aimed to identify the error rates in Catheter Calibration Mode, Auto Calibration Mode, and Segment Calibration Mode among many calibration modes as a quantitative evaluation tool used for predicting the diameter and length of balloon or stent in percutaneous intravascular balloon dilatation or stent insertion. Our experiment was conducted with Copper Wire of 2 mm × 80 mm (diameter × length) manufactured elaborately for quantitative evaluation in calibration and Metal Ball of 5, 10, 15, 30, and 40 mm and Acryl Phantom of 25 mm, 50 mm, 75mm, 100 mm, 125 mm, 150mm, 175 mm, and 200 mm. At each height, subtraction images were acquired with a cineangiograph and Stenosis Analysis Tool as a software provided by the equipment company was used for measurement. To evaluate the error rates in Catheter Calibration Mode, Copper Wire was put on each acryl phantom before shooting. Copper Wire of 2 mm in diameter was set as a diameter for catheter, and Copper Wire of 8 mm in length was measured with Multi-segments. As a result, the error rates appeared at 1.13 ~ 5.63%. To evaluate the error rates in Auto Calibration Mode, the height of acryl was entered at each height of acryl phantom and the length of 8 mm Copper Wire was measured with Multi-segments and as a result, the error rates appeared at 0 ~ 0.26%. To evaluate the error rates in Segment Calibration Mode, each metal ball on the floor of table was calibrated and the length of 8 mm Copper Wire on each acryl phantom was measured and the length of 8 mm Copper Wire depending on the changes of acryl phantom height was measured with Mutli-segments and as a result, the error rates appeared at 1.05 ~ 19.04%. And in the experiment on OID changes in Auto Calibration Mode, the height of acryl phantom was fixed at 100mm and OID only changed within the range of 450 mm ~ 600 mm and as a result, the error rates appeared at 0.13 ~ 0.38%. In conclusion, it was found that entering the height values in Auto Calibration Mode, among these Calibration Modes for evaluating quantitative vascular dimensions provided by the software was the calibration method with the least error rates and it is thus considered that for calibration using a metal ball or other objects, putting them in the same height as that of treatment sites before calibrating is the method that can reduce the error rates the most.

• Tuberculosis and Respiratory Diseases
• /
• v.72 no.6
• /
• pp.486-492
• /
• 2012

Background: The aim of this study was to analyze clinical situations requiring rigid bronchoscopy and evaluate usefulness of rigid bronchoscopic intervention in benign or malignant airway disorders. Methods: We retrospectively reviewed 29 patients who underwent rigid bronchoscopy from November 2007 to February 2011 at St. Paul's Hospital, The Catholic University of Korea School of Medicine. Results: Of the 29 patients, the most frequent underlying etiology was benign stenosis of trachea (n=20). Of those 20 patients, 16 had post-intubation tracheal stenosis (PITS), 2 had tracheal stenosis due to inhalation burn (IBTS) and other 2 had obstructive fibrinous tracheal pseudomembrane (OFTP). Other etiologies were airway malignancy (n=6), endobronchial stenosis due to tuberculosis (n=2), and foreign body (n=1). For treatment, silicone stent insertion was done in 16 cases of PITS and IBTS and mechanical removal was performed in 2 cases of OFTP. In 6 cases of malignant airway obstruction mechanical debulking was performed and silicone stents were inserted additionally in 2 cases. Balloon dilatation and electrocautery were used in 2 cases of endobronchial stenosis due to tuberculosis. In all cases of stent, airway obstructive symptom improved immediately. Granulation tissue formation was the most common complication. Conclusion: Tracheal stenosis was most common indication and silicone stenting was most common procedure of rigid bronchoscopy in our center. Rigid bronchoscopic procedures, at least tracheal silicone stenting, should be included in pulmonary medicine fellowship programs because it is a very effective and indispensable method to relieve critical airway obstruction which needs training to learn.

• Journal of Chest Surgery
• /
• v.43 no.6
• /
• pp.753-757
• /
• 2010

We report hereon a case of double bypass of the esophagus and descending thoracic aorta for the treatment of esophagopleural fistula and aortopleural fistula due to an infected aortic aneurysm after esophageal rupture. A 48 year old man was diagnosed as having esophageal rupture after an accidental explosion. Although he had been treated by esophageal repair and drainage at another hospital, the esophageal leakage could not be controlled and subsequent empyema developed in the left pleura. Further, bleeding from the descending thoracic aorta had developed and he was managed with endovascular stent insertion to the descending thoracic aorta. He was transferred to our hospital for corrective surgery. We performed esophago - gastrostomy via the substernal route, without exploring posterior mediastinum and we let the empyema resolve spontaneously. While he was being managed postoperatively Without any signs and symptoms of infection, sudden bleeding developed from the left pleural cavity. After evaluation for the bleeding focus, we discovered an Infected aortic aneurysm and an aortospleural fistula at the stent insertion site. We performed a second bypass procedure for the infected descending thoracic aorta from the ascending aorta to the descending abdominal aorta via the right pleural cavity. We found leakage at the distalligation site during the immediate postoperative period, and we occluded the leakage using a vascular plug. He discharged without complications and he is currently doing well without any more bleeding or other complications.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.7
• /
• pp.4651-4655
• /
• 2015

The subclavian artery pseudoaneurysm in blunt trauma is uncommon and rarely occurs secondary to penetrating injury. Subclavian artery injuries represent an uncommon complication of blunt chest trauma, this structure being protected by subclavius muscle, the clavicle, the first rib, and the deep cervical fascia as well as the costo-coracoid ligament, a clavi-coraco-axillary fascia portion. Subclavian artery injury appears early after trauma, and arterial rupture may cause life-threatening hemorrhages, pseudoaneurysm formation and compression of brachial plexus. Most injuries were related to clavicle fracture, gunshot, other penetrating trauma, and complication of central line insertion. The presence of large hematomas and pulsatile palpable mass in supraclavicular region should raise the suspicion of serious vascular injury and these clinical evidences must be carefully worked out by physical examination of the upper limb. Since the first reports of endovascular treatment for traumatic vascular injuries in the 1993, an increasing number of vascular lesions have been treated this way. We report a case of subclavian artery pseudoaneurysm 10 days after blunt chest trauma due to traffic accident, treated by endovascular stent grafting.

• The Journal of Korean Academy of Prosthodontics
• /
• v.56 no.1
• /
• pp.8-16
• /
• 2018

Purpose: The purpose of this study is to evaluate the accuracy of surgical stent according to the supported type. Materials and methods: 5 sets of dental models which have tooth supported edentulous area and tooth-tissue supported edentulous area were made. Dental model were scanned with model scanner, and CBCT was taken. CT data and model scan data were overlapped using In2Guide software, implant were virtually planned in the software. Surgical stents are fabricated by 3D printing. The implant fixture were installed using the surgical stent, CBCT were retaken. CBCT before surgery and after surgery were overlapped, and the differences (angle difference, coronal difference, apical difference) were evaluated using statistical analysis. Results: In the assessment of the accuracy of surgical guides according to arch type, there are no statistically significant differences between maxilla and mandible. In the case of support type, tooth supported stents showed lower angle difference and length difference than tooth-tissue supported stents, which are statistically significant. Conclusion: Arch type does not affect the accuracy of surgical stents. But tooth support stents are more accurate than tooth-tissue support stents in the case of angle and length difference.

• Polymer(Korea)
• /
• v.34 no.2
• /
• pp.178-183
• /
• 2010

Medical metal stents inserted to patients with a cardiovascular disease associated with coronary artery system have relatively increased the survival rate. The development of new stents is, however, urgently required due to restenosis and late thrombosis generated in metal stents. To solve these problems, the biodegradable polymers such as poly(lactide-co-glycolide) (PLGA), poly(L-lactide)(PLLA), and poly ($\varepsilon$-caprolactone)(PCL) were mixed with alpha lipoic acid (ALA), which is well known to inhibit the proliferation of neointimal hyperplasia. Subsequently, the ALA-loaded polymers were coated on stainless steel by electrospray. The drug-eluting behaviors from the coated polymers were investigated according to kinds and concentrations of polymers, spray rates, and kinds of solvents. The drug-eluting rate from PCL with the lowest glass transition temperature was the fastest among three polymers and followed by PLGA and PLLA. The surface roughness increased as the spray rate was increased and also the drug-eluting rate was affected by kinds of solvents with different boiling point. It is expected that drug-eluting stent (DES) coated with ALA-loaded polymers can be applied practically for clinical applications by controlling the behavior of drug release.

• Journal of Chest Surgery
• /
• v.42 no.5
• /
• pp.677-683
• /
• 2009

May-Thurner syndrome is a deep vein thrombosis of the ilio-femoral vein due to compression of the left common iliac vein by the overlying right common iliac artery. Although, catheter directed thrombectomy (CDT) and thrombolysis with stent insertion has become the standard treatment method for acute or subacute May-Thurner syndrome, because of technical feasibility and lower recurrence rate, however, sometimes this methods make fatal complications. Furthermore, there are few reports on optimal treatment strategies for patients in a chronic state of May-Thurner syndrome. We now present two cases of chronic (> 1 month since onset of symptoms) May-Thurner syndrome treated by surgical thrombectomy and femoral arteriovenous shunt with simultaneous stent insertion after failed endovascular treatment. This technique may provide a significant benefit for patients who are not suitable for conventional endovascular treatment.

• Tuberculosis and Respiratory Diseases
• /
• v.64 no.4
• /
• pp.298-302
• /
• 2008

We experienced a case of tuberculosis presented simultaneously with pseudoaneurysm of the aorta and ARDS. A 63-year-old man was admitted with complaints of fever and right upper quadrant abdominal pain for a week. Chest X-ray on admission showed a normal finding. Sub-diaphragmatic abscess on abdomen CT scan was suspected and serosanguinous fluid was aspirated from the abscess pocket. On day 2, he was getting more dyspneic and chest X-ray revealed extensive bilateral infiltration. Aspirated fluid revealed AFB. Later, follow-up abdomen CT scan revealed a leakage of dye from the aneurysmal sac of the descending aorta which was previously diagnosed as sub-diaphragmatic abscess. An aortic stent was placed, covering the opening into the aneurysm. The sputum also showed positive AFB. The patient was successfully weaned from the ventilator, and discharged with anti-tuberculous medication on day 42. Follow-up abdomen CT scan 6 months later showed that the aneurymal sac was completely disappeared.

• Imaging Science in Dentistry
• /
• v.33 no.2
• /
• pp.79-83
• /
• 2003

Purpose : To assess the relationship between the direction of the indicating rod of the radiographic stent for ideal prosthetic design and the actual possible path of implant fixture placement when residual ridge resorption is considered. Materials and Methods: The study materials consisted of 326 implant sites (male 214 cases and female 112 cases) from a total of 106 patients (male 65 patients and female 41 patients) who desired implant prostheses. Computed tomography of patients were taken and reformatted using ToothPix/sup (R)/ software. Bony defects, bony sclerosis, the change of the direction of indicating rod, and root proximity of the adjacent teeth were examined on the CT-derived images. Results: The rate of the irregular crestal cortex was relatively high on premolar and molar area of maxilla. Mandibular molar area showed relatively high rate of focal sclerosis on the area of implant fixture insertion. The position of the indicating rods were relatively acceptable on the molar areas of both jaws. However, the position of the indicating rods should be shifted to buccal side with lingual rotation of the apical end on maxillary anterior teeth and premolar area. Conclusion: Clinically determined rod direction and position of the indicating rod for implant placement was not always acceptable for insertion according to the reformatted CT images. The pre-operative treatment plan for implant should be determined carefully, considering the state of the alveolar bone using the reformatted CT images.

• Investigative Magnetic Resonance Imaging
• /
• v.19 no.2
• /
• pp.76-87
• /
• 2015

Purpose: There is an ongoing search for a stent material that produces a reduced susceptibility artifact. This study evaluated the effect of manganese (Mn) content on the MRI susceptibility artifact of ferrous-manganese (Fe-Mn) alloys, and investigated the correlation between MRI findings and measurements of Fe-Mn microstructure on X-ray diffraction (XRD). Materials and Methods: Fe-Mn binary alloys were prepared with Mn contents varying from 10% to 35% by weight (i.e., 10%, 15%, 20%, 25%, 30%, and 35%; designated as Fe-10Mn, Fe-15Mn, Fe-20Mn, Fe-25Mn, Fe-30Mn, and Fe-35Mn, respectively), and their microstructure was evaluated using XRD. Three-dimensional spoiled gradient echo sequences of cylindrical specimens were obtained in parallel and perpendicular to the static magnetic field (B0). In addition, T1-weighted spin echo, T2-weighted fast spin echo, and $T2^*$weighted gradient echo images were obtained. The size of the low-intensity area on MRI was measured for each of the Fe-Mn binary alloys prepared. Results: Three phases of ${\alpha}^{\prime}$-martensite, ${\gamma}$-austenite, and ${\varepsilon}$-martensite were seen on XRD, and their composition changed from ${\alpha}^{\prime}$-martensite to ${\gamma}$-austenite and/or ${\varepsilon}$-martensite, with increasing Mn content. The Fe-10Mn and Fe-15Mn specimens comprised ${\alpha}^{\prime}$-martensite, the Fe-20Mn and Fe-25Mn specimens comprised ${\gamma}+{\varepsilon}$ phases, and the Fe-30Mn and Fe-35Mn specimens exhibited a single ${\gamma}$ phase. The size of the low-intensity areas of Fe-Mn on MRI decreased relative to its microstructure on XRD with increasing Mn content. Conclusion: Based on these findings, proper conditioning of the Mn content in Fe-Mn alloys will improve its visibility on MR angiography, and a Mn content of more than 25% is recommended to reduce the magnetic susceptibility artifacts on MRI. A reduced artifact of Fe-Mn alloys on MRI is closely related to the paramagnetic constitution of ${\gamma}$-austenite and/or ${\varepsilon}$-martensite.