Safety and Effectiveness of Percutaneous Low-Dose Thrombin Injection for Femoral Puncture Site Pseudoaneurysms in Neurointervention: Single-Center Experience / 신경중재치료의학

Purpose@#We present ultrasound-guided percutaneous low-dose thrombin (200–250 IU) injection for the treatment of iatrogenic femoral pseudoaneurysms. Second, we compared patient and procedure factors between subcutaneous hematoma and pseudoaneurysm groups. @*Materials and Methods@#From April 2012 to May 2018, 8425 patients underwent neurointervention. Among these patients, 18 had small subcutaneous hematomas and 6 had pseudoaneurysms. Pseudoaneurysms in the neck and entire sac were visualized, and low-dose thrombins were injected while visualizing a “whirlpool” hyperechoic core in the pseudoaneurysm sac. Subcutaneous hematomas were treated with simple compression. We compared the following parameters between the subcutaneous hematoma group and pseudoaneurysm group: sex, age, body mass index (BMI), type of procedure, heparin usage, sheath size, procedure time, and number of previous neurointervention procedures with the Mann-Whitney U test. @*Results@#Most of the pseudoaneurysms were successfully occluded with 200 IU of thrombin (n=5). Only 1 pseudoaneurysm required a slightly higher thrombin concentration (250 IU, n=1). During the short-term follow-up, no residual sac was observed and no surgical repair was necessary. Pain in the groin region was alleviated. During the 1-month follow-up, no evidence of pseudoaneurysm recurrence nor subcutaneous hematoma was noted. Patient factors (sex, age, and BMI) and procedure factors (heparin usage, sheath size, procedure time, number of previous procedures) were not statistically different between the subcutaneous hematoma and pseudoaneurysm groups. @*Conclusion@#Ultrasound-guided percutaneous low-dose thrombin injection (200–250 IU) is safe, effective, and less invasive for treating iatrogenic femoral pseudoaneurysm in neurointervention.

Efficiency of Air Bubble Removal in Preparation of Low-Profile Angioplasty Balloon Catheter: Bench-Top Comparison of Six Methods / 신경중재치료의학

PURPOSE: Complete removal of air bubbles from balloons for neurovascular angioplasty is cumbersome. We compared the preparation difficulty, air removal efficiency, and air collection pattern of six different balloon catheter preparation methods to propose a better preparation method for both initial and second balloon uses, especially for small-profile angioplasty balloon catheters. MATERIALS AND METHODS: A total of 18 neurovascular angioplasty balloon catheters with nominal diameters of 2 mm were prepared to test six different preparation methods: the instruction for use method (method A), simplified method using a syringe (method B) and four newly devised preparation methods using inflating devices (methods C–F). Serial radiographs were obtained while the balloons were gradually inflated. We measured the time for each preparation and the bubble number, analyzed their distribution in the balloon, and calculated the contrast filling ratio (contrast filling area/total balloon area) for initial and second ballooning. The whole process was repeated three times. RESULTS: The preparation time varied widely (11.5 seconds [method D] to 73.3 seconds [method A]). On initial inflation, the contrast filling ratio at 8 atm was the highest (100%) with methods A and F. On second inflation, the ratio was again highest with method A (99.5%), followed by method F (99.2%). Initial ballooning tended to show a uniform pattern of single bubble in the distal segment of the balloon; in contrast, second ballooning showed varying patterns in which the bubbles were multiple and randomly distributed. CONCLUSION: None of the six methods were able to completely exclude air bubbles from the balloon catheters including the second ballooning; however, the method of repeating aspiration with high-volume inflating device (method F) could be a practical option considering the simplicity and efficiency of preparation.

Cigarette Smoking Preferentially Affects Intracranial Vessels in Young Males: A Propensity-Score Matching Analysis / 신경중재치료의학

PURPOSE: Cigarette smoking (CS) is one of the major risk factors of cerebral atherosclerotic disease, however, its level of contribution to extracranial and intracranial atherosclerotic stenosis (ECAS and ICAS) was not fully revealed yet. The purpose of our study was to assess the association of CS to cerebral atherosclerosis along with other risk factors. MATERIALS AND METHODS: All consecutive patients who were angiographically confirmed with severe symptomatic cerebral atherosclerotic disease between January 2002 and December 2012 were included in this study. Multivariate logistic regression analyses were performed to identify risk factors for ECAS and ICAS. Thereafter, CS group were compared to non-CS group in the entire study population and in a propensity-score matched population with two different age-subgroups. RESULTS: Of 1709 enrolled patients, 794 (46.5%) had extracranial (EC) lesions and the other 915 (53.5%) had intracranial (IC) lesions. CS group had more EC lesions (55.8% vs. 35.3%, P<0.001) whereas young age group (<50 years) had more IC lesion (84.5% vs. 47.6%, P<0.001). In multivariate analysis, seven variables including CS, male, old age, coronary heart disease, higher erythrocyte sedimentation rate, multiple lesions, and anterior lesion were independently associated with ECAS. In the propensity-score matched CS group had significant more EC lesion compared to non-CS group (65.7% vs. 47.9%) only in the old age subgroup. CONCLUSION: In contrast to a significant association between CS and severe symptomatic ECAS shown in old population, young patients did not show this association and showed relatively higher preference of ICAS.

In Vitro Evaluation of Fusiform-Shaped Stents for Wide-Neck Intracranial Aneurysm Treatment / 신경중재치료의학

PURPOSE: Wide-neck aneurysms (WNAs) associated with a dilated parent artery (PA) are not uncommon morphological abnormalities and usually cause inappropriate wall apposition and incomplete neck coverage of a tubular stent in stent-assisted coiling of aneurysms. We aimed to introduce a fusiform-shaped stent (FSS) and test its effectiveness in treating intracranial WNAs associated with a dilated PA using a three-dimensional (3D) model. MATERIALS AND METHODS: Two FSS types were designed with the middle one-third segment dilated by 10% (FSS10) and 20% (FSS20) and were compared with the tubular-shaped stent (TSS). A patient-specific 3D WNA model was prototyped and produced, and in vitro stent placement was performed. Angiographic images of the three stent types were analyzed and compared using predetermined parameters. RESULTS: The stent lumens were significantly larger in FSS10 and FSS20 than in TSS in the middle segments (P=0.046), particularly FSS20 (P=0.018). The non-covered area at the ostium tended to be smaller in FSS10 and FSS20 than in TSS, but the difference was not significant (P>0.05). The stent length was significantly longer in FSS10 and FSS20 than in TSS. The stent cell size was significantly larger in FSS than in TSS. CONCLUSION: Better vessel wall apposition and aneurysmal neck coverage was observed for FSS than for TSS. No significant difference was observed between FSS10 and FSS20.

A Study Design to Evaluate Association between Smoking and Intracranial Atherosclerotic Stenosis / 신경중재치료의학

PURPOSE: Smoking is a well known risk factor for stroke. The cerebral arteries may be uniquely susceptible to the atherosclerotic effects of smoking, such that it has a different risk profile for stroke compared with other atherosclerosis risk factors. It remains uncertain whether smoking is associated specifically with intracranial (IC) or extracranial (EC) atherosclerotic cerebrovascular disease. The aim of this study design will be to evaluate the association between smoking and severe IC stenosis, adjusting for other atherosclerosis risk factors, particularly age distribution. STUDY DESIGN: This is a retrospective cohort study design. Participants are patients (n=1714) with severe atherosclerotic stenosis undergoing cerebral catheter angiography because of stroke or transient ischaemic attack. All atherosclerotic steno-occlusive lesions are described in terms of location (anterior versus posterior circulation, IC versus EC, or intradural versus extradural). The atherosclerotic or stroke risk factors for analysis include age, gender, smoking history, number of lesions (single versus multiple), cardiac disease, diabetes mellitus, hypertension, family history, dyslipidemia, history of previous stroke, alcohol intake, metabolic syndrome and body mass index. Statistical analysis includes univariate analysis followed by multivariate logistic regression. The relationship between IC atherosclerotic stenosis and smoking will be assessed. Differences in risk factor distribution is analysed according to age at intervals of 10 years. Significant risk factors associated with IC atherosclerotic stenosis will also be assessed by multivariate logistic regression analysis. SUMMARY: This is an analytical study design that intends to measure the association between IC or EC atherosclerotic stenosis and smoking and other risk factors. We anticipate that it will have the power to detect any relationship between smoking and IC atherosclerotic lesions especially in younger patients.

Current Status of Neurointerventional Activities in Korea / 신경중재치료의학

Neurointervention which deals with neurovascular disease in brain, head-and-neck and spines are one of the rapidly evolving medical fields. Several indices representing neurointerventional activities are still increasing year-by-year in Korea. We review current trend in major neurovascular diseases requiring usage of specific medical devices and some issues related to administrative process of the government approval.

In Vitro Observation of Air Bubbles during Delivery of Various Detachable Aneurysm Embolization Coils

OBJECTIVE: Device- or technique-related air embolism is a drawback of various neuro-endovascular procedures. Detachable aneurysm embolization coils can be sources of such air bubbles. We therefore assessed the formation of air bubbles during in vitro delivery of various detachable coils. MATERIALS AND METHODS: A closed circuit simulating a typical endovascular coiling procedure was primed with saline solution degassed by a sonification device. Thirty commercially available detachable coils (7 Axium, 4 GDCs, 5 MicroPlex, 7 Target, and 7 Trufill coils) were tested by using the standard coil flushing and delivery techniques suggested by each manufacturer. The emergence of any air bubbles was monitored with a digital microscope and the images were captured to measure total volumes of air bubbles during coil insertion and detachment and after coil pusher removal. RESULTS: Air bubbles were seen during insertion or removal of 23 of 30 coils (76.7%), with volumes ranging from 0 to 23.42 mm3 (median: 0.16 mm3). Air bubbles were observed most frequently after removal of the coil pusher. Significantly larger amounts of air bubbles were observed in Target coils. CONCLUSION: Variable volumes of air bubbles are observed while delivering detachable embolization coils, particularly after removal of the coil pusher and especially with Target coils.

Optimization of Exposure Condition and Photographic Techniques for Specimen and Devices in Neuroangiographic Suites / 신경중재치료의학

PURPOSE: We analyzed factors related to quality of photographs taken at neuroangiographic suites to optimize exposure condition. MATERIALS AND METHODS: We used a camera (EOS-300D, Canon Inc., Tokyo) with a standard- (EF-S 18-55 mm F3.5-5.6 USM, Canon Inc., Tokyo) and a macro-lens (EF 100 mm f/2.8 Macro USM, Canon Inc., Tokyo). Photographs were taken at a light-booth (1000 lux) and 2 neuroangiographic suites (988 and 856 lux) under ordinary intensity of illumination. We took photographs of a test chart (ColorChecker, X-rite, Michigan) and Kodak Q-13 Grey Scale Card at different values of aperture and shutter speed with fixed ISO of 400 and assessed the quality of photographs by Blade Pro (V1.1, Image group, Seoul). We analyzed photographs of a device at 1/25-1/80 shutter speed and F12 - 20 apertures and compared the result and also made visual assessment. RESULTS: Photographs of test chart and Grey Scale Card revealed that the best images chosen by Blade Pro were distributed in scattered range of quality which could help understand the range of optimum exposure condition but was not suitable for practical usage. We obtained reasonable quality photograph at shutter speed of 1/40 and aperture of F16 that can be used in 3 places. CONCLUSION: The most appropriate exposure condition when taking photographs in neuroangiographic suites could be explored. To get an optimal image in limited illumination, it is mandatory to select a fast enough shutter speed to avoid motion artifacts and a sufficient aperture to actualize the subject depth.

Design and Management of Database Using Microsoft Access Program: Application in Neurointerventional Unit

PURPOSE: Complex clinical information in cerebral angiointervention unit requires effective management of statistical analysis for the classification of diagnosis and intervention including follow-up data from the interventional treatment. We present an application of Microsoft Access program for the management of patient data in cerebral angiointervention unit which suggests practical methods in recording and analyzing the patient data. MATERIALS AND METHODS: Since January 2002, patient information from cerebral angiointervention was managed by a database with over 4000 patients. We designed a program which incorporates six items; Table, Query, Form, Report, Page and Macro. Patient data, follow-up data and information regarding diagnosis and intervention were established in the Form section, related by serial number, and connected to each other to an independent Table. Problems in running the program were corrected by establishing Entity Relationship (ER) diagrams of Tables to define relationships between Tables. Convenient Queries, Forms and Reports were created to display expected information were applied from selected Tables. RESULTS: The relationship program which incorporated six items conveniently provided the number of cases per year, incidence of disease, lesion site, and case analysis based on interventional treatment. We were able to follow the patients after the interventional procedures by creating queries and reports. Lists of disease and patients files were identified easily each time by the Macro function. In addition, product names, size and characteristics of materials used were indexed and easily available. CONCLUSION: Microsoft Access program is effective in the management of patient data in cerebral angiointervention unit. Accumulation of large amounts of complex data handled by multiple users may require client/sever solutions such as a Microsoft SQL Server.