Sung-Choon Park

Bilateral Approach for Stent-assisted Coiling of Posterior Inferior Cerebellar Artery Aneurysms - Two Cases

Aneurysms of the posterior inferior cerebellar artery (PICA) are rarely encountered. In particular, due to frequent anatomic complexity and the presence of nearby critical structures, PICA origin aneurysms are difficult to treat. However, recent reports of anecdotal cases using advanced endovascular instruments and skills have made the results of endovascular treatment rather outstanding. PICA preservation is the key to a successful endovascular treatment, based on the premise that a PICA origin aneurysm is well occluded. To secure PICA flow, stenting into the PICA would be the best method, however, it is nearly impossible technically via the ipsilateral vertebral artery (VA) if the PICA arose at an acute angle from the sac. In such a case, a bilateral approach for stent-assisted coiling can be a creative method for achievement of two goals of both aneurysm occlusion and PICA preservation: ipsilateral approach for coil delivery and contralateral cross-over approach for stent delivery via a retrograde smooth path into the PICA.

Cerebral Hemorrhage after Endovascular Treatment of Bilateral Traumatic Carotid Cavernous Fistulae with Covered Stents

Bilateral traumatic carotid-cavernous fistulae (TCCFs) is rarely encountered neurovascular disease. For treatment of TCCF, detachable balloons have been widely used. Nowadays, transarterial and/or transvenous coil embolization with placement of covered stents is adopted as another treatment method. We experienced a patient with a bilateral TCCFs who was successfully treated with covered stents. However, cerebral hemorrhage occurred in the bed of previous infarction one day after treatment. Hyperperfusion syndrome was considered as a possible cause of the hemorrhage, so that barbiturate coma therapy was started and progression of hemorrhage was stopped. We emphasize that cerebral hyperperfusion hemorrhage can occur even after successful endovascular treatment of TCCF.

Ruptured and unruptured aneurysms of the accessory anterior cerebral artery combined with a blood blister-like aneurysm of the anterior communicating artery

Anterior communicating artery (Acom) complex and anterior cerebral artery (ACA) are the frequent sites of arterial anomalies. Aneurysms associated with triplicate ACA are rare. Blood blister-like aneurysm (BBA) of the Acom is also very rare. This report presents these two rare types of aneurysms in a 63-year old man who presented with subarchnoid hemorrhage secondary to accessory ACA aneurysmal rupture. During surgery, a BBA of the Acom was also found. Both the aneurysms were treated simultaneously. The BBA bled intraprocedurally but was repaired successfully by neck reconstruction and clipping with the preservation of the parent and the branching arteries. The ruptured accessory ACA aneurysm was clipped together with the artery which had multiple aneurysms distally. For the treatment of a complex aneurysm like this, accurate understanding of the anatomic variations, proper imaging study and extremely careful technique are essential.

Time Course and Characteristics of Astrocyte Activation in the Rat Brain after Injury

Objective After injury to the central nervous system (CNS), glial scar tissue is formed in the process of wound healing. This can be is a clinical problem because it interferes with axonal regeneration and functional recovery. It is known that intracellular proteins, including the glial fibrillary acidic protein (GFAP), nestin, and vimentin increase in the astrocytes after an injury to the CNS. By studying the time course and co-expression pattern of these intracellular proteins, this study will attempt to prove that these proteins are involved in the processes of glial scar formation. Methods Twenty-five male Sprague-Dawley rats were used in this study. Bregma of the cerebral cortex, an area was incised with a sharp blade, and perfusion was performed. The expressions of the intracellular proteins were assayed, while the co-localization of the intermediate filament (GFAP, nestin, and vimentin) and A2B5 were examined. Results At 12 hours, the GFAP was expressed in the white matter underlying the lesion, and in the cerebral cortex. Nestin was expressed in the astrocytes in the perilesional area after 3 days, while A2B5 was observed in the edge of the wound at 12 hours post-injury, with its expression reaching a peak at 7 days. Vimentin was detected in the white matter at 12 hours, and in the cortex, reaching a peak at 7 days. Conclusion In the processes of glial scar formation, nestin, vimentin, and A2B5 were revealed in the astrocytes, and these factors may be involved in the division, proliferation, and transportation of the astrocytes.

A comparative result of ventriculoperitoneal shunt, focusing mainly on gravity-assisted valve and programmable valve.

OBJECTIVE Despite rapid evolution of shunt devices, the complication rates remain high. The most common causes are turning from obstruction, infection, and overdrainage into mainly underdrainage. We investigated the incidence of complications in a consecutive series of hydrocephalic patients. METHODS From January 2002 to December 2009, 111 patients underwent ventriculoperitoneal (VP) shunting at our hospital. We documented shunt failures and complications according to valve type, primary disease, and number of revisions. RESULTS Overall shunt survival time was 268 weeks. Mean survival time of gravity-assisted valve (GAV) was 222 weeks versus 286 weeks for other shunts. Survival time of programmable valves (264 weeks) was longer than that of pressure-controlled valves (186 weeks). The most common cause for shunt revision was underdrainage (13 valves). The revision rate due to underdrainage in patients with GAV (7 of 10 patients) was higher than that for other valve types. Of 7 patients requiring revision for GAV underdrainage, 6 patients were bedridden. The overall infection rate was 3.6%, which was lower than reported series. Seven patients demonstrating overdrainage had cranial defects when operations were performed (41%), and overdrainage was improved in 5 patients after cranioplasty. CONCLUSION Although none of the differences was statistically significant, some of the observations were especially notable. If a candidate for VP shunting is bedridden, GAV may not be indicated because it could lead to underdrainage. Careful procedure and perioperative management can reduce infection rate. Cranioplasty performed prior to VP shunting may be beneficial.

Comparative Clinical Results of Vertebroplasty Using Jamshidi® Needle and Bone Void Filler for Acute Vertebral Compression Fractures

Objective Percutaneous vertebroplasty (PVP) is an effective treatment modality for management of osteoporotic compression fracture. However physicians sometimes have problems of high pressure in cement delivery and cement leakage when using Jamshidi® needle (JN). Bone void filler (BVF) has larger lumen which may possibly diminish these problems. This study aims to compare the radiologic and clinical outcome of JN and BVF for PVP. Methods One hundred twenty-eight patients were treated with PVP for osteoporotic vertebral compression fracture (VCF) where 46 patients underwent PVP with JN needle and 82 patients with BVF. Radiologic outcome such as kyphotic angle and vertebral body height (VBH) and clinical outcome such as visual analog scale (VAS) scores were measured after treatment in both groups. Results In JN PVP group, mean of 3.26 cc of polymethylmethacrylate (PMMA) were injected and 4.07 cc in BVF PVP group (p<0.001). For radiologic outcome, no significant difference in kyphotic angle reduction was observed between two groups. Cement leakage developed in 6 patients using JN PVP group and 2 patients using BVF group (p=0.025). No significant difference in improvement of VAS score was observed between JN and BVF PVP groups (p=0.43). Conclusion For the treatment of osteoporotic VCF, usage of BVF for PVP may increase injected volume of cement, easily control the depth and direction of PMMA which may reduce cement leakage. However, improvement of VAS score did not show difference between two groups. Usage of BVF for PVP may be an alternative to JN PVP in selected cases.