• Journal of Korean Neurosurgical Society
• /
• v.59 no.4
• /
• pp.341-345
• /
• 2016

Objective : Solitaire AB stent-assisted coiling facilitates the endovascular treatment of wide-necked intracranial aneurysms. We present our experience of coiling the micro-aneurysms of wide-neck with Solitaire AB stent assisting in a single center. Methods : Thirty-one Solitaire AB stents were used to treat via endovascular approach patients with 31 wide-neck micro aneurysms in a single center in China. Technical and clinical complications were recorded. Modified Rankin Scale was used to evaluate the patients' conditions via clinic and telephone follow-up. Results : The mean width of aneurysm sac was $2.30{\pm}0.42mm$, and the mean diameter of aneurysm neck was $2.83{\pm}.48mm$. Complete occlusion was achieved in 28 aneurysms (90.32%); neck remnant was seen in 3 aneurysms (9.68%). Technical and clinical complications related to the procedure were encountered in four patients (12.5%). Two patients died (6.25%). No patient had a permanent deficit. Conclusion : Solitaire AB stent was a safe and efficiency tool in assisting coiling of micro aneurysms with wide neck, but may be not suitable for a blaster-like one. Mid- and long-term follow-up will be required to elucidate the impact of the Solitaire AB stent on recanalization rate.

• Journal of Biomedical Engineering Research
• /
• v.23 no.5
• /
• pp.375-383
• /
• 2002

Aneurysm embolisation method using coils have been widely used. Micro coils are introduced via a small catheter, and are packed inside of aneurysm sac, which induces intraaneurysmal flow stagnation and thrombus formation. When partial blocking of an aneurysm is inevitable, the location of coils is important since it changes the flow patterns inside the aneurysm, which affect the embolisation process. We measured the flow field inside the partially blocked lateral aneurysm models in vitro, and tried to suggest the effective locations of coils for aneurysm embolisation. Velocity fields are measured using a particle image velocitimeter for different coil locations- proximal neck, distal neck, proximal dome and distal dome. Flow into the aneurysm sac was significantly reduced in the distally blocked models, and coils at distal neck blocked inflow more effectively comparing to those at distal dome. This study suggests that distal neck should be the most effective location for aneurysm embolisation.

• Biomaterials and Biomechanics in Bioengineering
• /
• v.2 no.2
• /
• pp.71-84
• /
• 2015

A low-profile flow sensor has been designed, fabricated, and characterized to demonstrate the feasibility for monitoring hemodynamics in cerebral aneurysm. The prototype device is composed of three micro-membranes ($500-{\mu}m$-thick polyurethane film with $6-{\mu}m$-thick layers of nitinol above and below). A novel super-hydrophilic surface treatment offers excellent hemocompatibility for the thin nitinol electrode. A computational study of the deformable mechanics optimizes the design of the flow sensor and the analysis of computational fluid dynamics estimates the flow and pressure profiles within the simulated aneurysm sac. Experimental studies demonstrate the feasibility of the device to monitor intra-aneurysmal hemodynamics in a blood vessel. The mechanical compression test shows the linear relationship between the applied force and the measured capacitance change. Analytical calculation of the resonant frequency shift due to the compression force agrees well with the experimental results. The results have the potential to address important unmet needs in wireless monitoring of intra-aneurysm hemodynamic quiescence.

• Journal of Korean Neurosurgical Society
• /
• v.42 no.4
• /
• pp.281-285
• /
• 2007

Objective : Distal anterior cerebral artery (DACA) aneurysms are fragile and known to have high risks for intraoperative premature rupture and a relatively high associated morbidity. To improve surgical outcomes of DACA aneurysms, we reviewed our surgical strategy and its results postoperatively. Methods : A total of 845 patients with ruptured cerebral aneurysms were operated in our hospital from January 1991 to December 2005. Twenty-three of 845 patients had ruptured DACA aneurysms which were operated on according to our surgical strategy. Our surgical strategy was as follows; early surgery, appropriate releasing of CSF, appropriate surgical approach, using neuronavigating system, securing the bridging veins, using temporary clipping and/or tentative clipping, meticulous manipulation of aneurysm, and using micro-Doppler flow probe. Twenty of 23 patients who had complete medical records were studied retrospectively. We observed the postoperative radiographic findings and checked Glasgow Outcome Scale score sixth months after the operation. Results : Nineteen DACA aneurysms were clipped through a unilateral interhemispheric approach and one DACA aneurysm was clipped through a pterional approach. Postoperative radiographic findings revealed complete clipping of aneurysmal neck without stenosis or occlusion of parent arteries. In two patients, a residual neck of aneurysm was visualized. Seventeen patients showed good recovery, one patient resulted in moderate disability, while 2 patients died. Conclusion : With our surgical strategy it was possible to achieve acceptable surgical morbidity and mortality rates in patients with DACA aneurysms. Appropriate use of tentative clipping, temporary clipping and neuro-navigating systems can give great help for safe approach and clipping of DACA aneurysm.

• Archives of Plastic Surgery
• /
• v.38 no.3
• /
• pp.315-318
• /
• 2011

Purpose: An aneurysm is defined as a permanent, localized dilation of an artery with a 50% increase in diameter over its expected normal diameter. Aneurysms can be classified by cause as traumatic and nontraumatic. Traumatic aneurysms can be divided into true and false aneurysms. Nontraumatic causes of peripheral artery aneurysms include mycotic, atherosclerotic, inflammatory, and idiopathic. In the hand, true aneurysms occurring at the common digital artery have been rarely reported. We present a rare case of a true aneurysm of the common digital artery that was resected and reconstructed using a reversed vein graft. Methods: A 49-year-old male patient was refered to our institution with a $0.73{\times}0.44{\times}1.37cm$ sized pulsating mass between 2nd and 3rd flexor digitorum tendons on Lt. palm area. The mass had been present for 5 years and had increased in size over the previous year. No history of trauma was reported. After a physical examination and ultrasound sonography review, a diagnosis of aneurismal dilatation of common digital artery was made. Surgical treatment by excision of the aneurysm, and a reversed vein graft was performed. Results: Histologic examination of the specimen ($3.4{\times}0.7cm$) showed aneurismal dilatation, with elastin fibers present in the arterial wall. The lesions were healed without any complications and there were no evidence of recurrence. Doppler examination of the reconstruction showed good perfusion. Conclusion: Early excision is recommended to relieve symptoms and avoid neurologic damage. Also, artery reconstruction can be performed by primary end-to-end anastomosis or the placement of a reversed interposition vein graft. Micro surgical repair was the only possible treatment in this case. The authors believe that the vascular anatomy should always be restored as natural as possible.

• Journal of Korean Neurosurgical Society
• /
• v.53 no.2
• /
• pp.72-76
• /
• 2013

Objective : Cerebral aneurysm (CA) is an important acquired cerebrovascular disease that can cause catastrophic results. MicroRNAs (miRNAs) are small non-coding RNAs, playing essential roles in modulating basic physiologic and pathological processes. Currently, evidences have been established about biologic relationship between miRNAs and abdominal aortic aneurysms. However, biologic roles of miRNAs in CA formation have not been explained yet. We employed microarray analysis to detect and compare miRNA expression profiles in late stage of CA in rat model. Methods : Twenty-six, 7-week-old male Sprague-Dawley rats underwent a CA induction procedure. The control animals (n=11) were fed a normal diet, and the experimental animals (n=26) were fed a normal diet with 1% normal saline for 3 months. Then, the rats were sacrificed, their cerebral arteries were dissected, and the five regions of aneurysmal dilation on the left posterior communicating artery were cut for miRNA microarrays analysis. Six miRNAs (miRNA-1, miRNA-223, miRNA-24-1-5p, miRNA-551b, miRNA-433, and miRNA-489) were randomly chosen for validation using real-time quantitative PCR. Results : Among a set of differentially expressed miRNAs, 14 miRNAs were over-expressed more than 200% and 6 miRNAs were down-expressed lower than 50% in the CA tissues. Conclusion : The results show that miRNAs might take part in CA formation probably by affecting multiple target genes and signaling pathways. Further investigations to identify the exact roles of these miRNAs in CA formation are required.

• Journal of Korean Neurosurgical Society
• /
• v.65 no.6
• /
• pp.772-778
• /
• 2022

Objective : Endovascular treatment of large, wide-necked intracranial aneurysms by coil embolization is often complicated by low rates of complete occlusion and high rates of recurrence. A flow diverter device has been shown to be safe and effective for the treatment of not only large and giant unruptured aneurysms, but small and medium aneurysms. However, in Korea, its use has only recently been approved for aneurysms <10 mm. This study aims to compare the safety and efficacy of flow diversion and coil embolization for the treatment of unruptured aneurysms ≥7 mm. Methods : The participants will include patients aged between 19 and 75 years to be treated for unruptured cerebral aneurysms ≥7 mm for the first time or for recurrent aneurysms after initial endovascular coil embolization. Participants assigned to a flow diversion cohort will be treated using any of the following devices : Pipeline Flex Embolization Device with Shield Technology (Medtronic, Minneapolis, MN, USA), Surpass Evolve (Stryker Neurovascular, Fremont, CA, USA), and FRED or FRED Jr. (MicroVention, Tustin, CA, USA). Participants assigned to a coil embolization cohort will undergo traditional endovascular coiling. The primary endpoint will be complete occlusion confirmed by cerebral angiography at 12 months after treatment. Secondary safety outcomes will evaluate periprocedural and post-procedural complications for up to 12 months. Results : The trial will begin enrollment in 2022, and clinical data will be available after enrollment and follow-up. Conclusion : This article describes the aim and design of a multi-center, randomized, open-label trial to compare the safety and efficacy of flow diversion versus traditional endovascular treatment for unruptured cerebral aneurysms ≥7 mm.