• Journal of Korean Neurosurgical Society
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• v.40 no.3
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• pp.193-195
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• 2006

Hydrocephalus is usually defined as the condition of ventricular dilatation due to the overproduction of cerebrospinal fluid[CSF] or dysfunction of absorption. The pattern of the CSF circulation may change after a cranioplasty secondary to previous decompressive craniectomy for refractory intracranial hypertension after head injury. The effect of the cranioplasty on CSF hydrodynamics has not been explored exactly. We report two cases of acute hydrocephalus developed after cranioplasty and discuss about the clinical importance with review of literatures.

• Proceedings of the KSMRM Conference
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• 1996.10a
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• pp.66-66
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• 1996

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3264-3274
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• 2021

In a severe accident of light water reactor (LWR), molten core material (corium) can be released into the wet cavity, and a fuel-coolant interaction (FCI) can occur. The molten jet with high speed is broken and fragmented into small debris, which may cause a steam explosion or a molten core concrete interaction (MCCI). Since the premixing stage where the jet breakup occurs has a large impact on the severe accident progression, the understanding and evaluation of the jet breakup phenomenon are highly important. Therefore, in this study, the jet breakup simulations were performed using the Smoothed Particle Hydrodynamics (SPH) method which is a particle-based Lagrangian numerical method. For the multi-fluid system, the normalized density approach and improved surface tension model (CSF) were applied to the in-house SPH code (single GPU-based SOPHIA code) to improve the calculation accuracy at the interface of fluids. The jet breakup simulations were conducted in two cases: (1) jet breakup without structures, and (2) jet breakup with structures (control rod guide tubes). The penetration depth of the jet and jet breakup length were compared with those of the reference experiments, and these SPH simulation results are qualitatively and quantitatively consistent with the experiments.

• Journal of Korean Neurosurgical Society
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• v.60 no.3
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• pp.301-305
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• 2017

Multiloculated hydrocephalus (MLH) is a condition in which patients have multiple, separate abnormal cerebrospinal fluid collections with no communication between them. Despite technical advancements in pediatric neurosurgery, neurological outcomes are poor in these patients and the approach to this pathology remains problematic especially given individual anatomic complexity and cerebrospinal fluid (CSF) hydrodynamics. A uniform surgical strategy has not yet been developed. Current treatment options for MLH are microsurgical fenestration of separate compartments by open craniotomy or endoscopy, shunt surgery in which multiple catheters are placed in the compartments, and combinations of these modalities. Craniotomy for fenestration allows better visualization of the compartments and membranes, and it can offer easy fenestration or excision of membranes and wide communication of cystic compartments. Hemostasis is more easily achieved. However, because of profound loss of CSF during surgery, open craniotomy is associated with an increased chance of subdural hygroma and/or hematoma collection and shunt malfunction. Endoscopy has advantages such as minimal invasiveness, avoidance of brain retraction, less blood loss, faster operation time, and shorter hospital stay. Disadvantages are also similar to those of open craniotomy. Intraoperative bleeding can usually be easily managed by irrigation or coagulation. However, handling of significant intraoperative bleeding is not as easy. Currently, endoscopic fenestration tends to be performed more often as initial treatment and open craniotomy may be useful in patients requiring repeated endoscopic procedures.