• Journal of Korean Neurosurgical Society
• /
• v.58 no.2
• /
• pp.141-143
• /
• 2015

Among the distal anterior inferior cerebellar artery (AICA) aneurysms, a unique aneurysm at the meatal loop inside the internal auditory meatus is extremely rare. The authors report a case of surgically treated total intrameatal AICA aneurysm. A 62-year-old female patient presenting with sudden bursting headache and neck pain was transferred to our department. Computed tomography and digital subtraction angiography showed subarachnoid hemorrhage at the basal, prepontine cistern and an aneurysm of the distal anterior inferior cerebellar artery inside the internal auditory meatus. Surgery was performed by retrosigmoid craniotomy with unroofing of the internal auditory meatus. The aneurysm was identified between the seventh and eighth cranial nerve in the meatus and was removed from the canal and clipped with a small straight Sugita clip. After operation the patient experienced transient facial paresis and tinnitus but improved during follow up.

• Journal of Korean Neurosurgical Society
• /
• v.40 no.2
• /
• pp.69-73
• /
• 2006

Objective : The optimal surgical treatment for symptomatic middle cranial fossa arachnoid cysts is controversial. Therapeutic options include endoscopic fenestration, excision, cyst shunting, and craniotomy for fenestration of basal cistern. We reviewed the results of surgically treated middle cranial fossa arachnoid cysts. Methods : We performed a retrospective study in 18 cases of middle cranial fossa arachnoid cysts who had been treated with microsurgical fenestration between 1995 to 2003. The analysis was based on the results of the patients' age, sex distribution, developed area, clinical symptoms, treatment method, and complications. Results : Eighteen surgical treated middle cranial fossa arachnoid cysts patients were evaluated. The age range of cyst development was between 2 years and 44 years with the average of 16.4 years. The follow-up periods averaged 31.48 months. There were 15 male and 3 female patients, with significantly more cyst development in males than females. The most common clinical symptom was headache, followed by seizure. In the entire series, 77.8% of patients demonstrated a decrease in cyst size In serial imaging studies. Of them, 67.3% demonstrated a complete cyst effacement. Overall, 100% of patients with Grade I cysts, 81.8% of patients with Grade II cysts, 60% of patients with Grade III cysts exhibited evidence of decrease in cyst size during long-term monitoring. Complications included headache, meningitis, and hydrocephalus. Conclusion : Patients who were treated with microsurgical fenestration showed good outcome with acceptable complications. We concluded that microsurgical fenestration is a safe and effective surgical method for middle cranial fossa arachnoid cysts.

• Smart Structures and Systems
• /
• v.4 no.2
• /
• pp.233-245
• /
• 2008

For historical masonry structures existing in the Mediterranean area, structural strengthening is of primary importance due to the continuous earthquake threat that is posed on them. Proper retrofitting of historical structures involves a thorough understanding of their structural pathology, before proceeding with any intervention measures. In this paper, a methodology is presented for the evaluation of the actual state of historical masonry structures, which can provide a useful tool for the seismic response assessment before and after the retrofitting. The methodology is mainly focused on the failure and vulnerability analysis of masonry structures using the finite element method. Using this methodology the retrofitting of historical structures with innovative techniques is investigated. The innovative technique presented here involves the exploitation of Shape Memory Alloy prestressed bars. This type of intervention is proposed because it ensures increased reversibility and minimization of interventions, in comparison with conventional retrofitting methods. In this paper, a case study is investigated for the demonstration of the proposed methodologies and techniques, which comprises a masonry Byzantine church and a masonry Cistern. Prestressed SMA alloy bars are placed into the load-bearing system of the structure. The seismic response of the non-retrofitted and the retrofitted finite element models are compared in terms of seismic energy dissipation and displacements diminution.

• Applied Microscopy
• /
• v.28 no.1
• /
• pp.83-90
• /
• 1998

The pathway of intracellular transport of dehydrocholic acid was investigated in the hepatocytes of rats by transmission electron microscopy with conventional and freeze fracture methods. Both in normal and experimental groups, the cis Golgi cisterns were sacculated and faces toward the bile canaliculus. In the experimental group, however, the cis Golgi cisterns showed buds, which were probably separated to be vesicles. Some of the buds were connected to the cisterns with the narrow neck. The vesicles were increased in the vicinity of bile canaliculi. The fusion between vesicles and bile canaliculus were frequently observed in the experimental group. This was particularly well shown in the freeze fracture replica. In the thin section, the vesicles were devoid of visible contents as seen in the bile canaliculli. The evidence suggests that the vesicles are derived from the cis Gogi cistern in the way that buds pinch off, serve as vehicles to transport dehydrocholic acids and fuse to bile canaliculi for exocytosis.

• Korean journal of applied entomology
• /
• v.31 no.4
• /
• pp.486-491
• /
• 1992

The aboveground activities of the larger black chafer (Holotrichia morosa Waterhouse) and the Korean black chafer (H. diomphalia Bates) adults were investigated in the field and laboratory from 1991 through 1992. In a field cage, H. morosa adults emerged from the ground between 7 : 40-9 : 00 p.m. and H. diomphalia adults emerged between 7 : 30-10 : 00 p.m. After emergence, both females and males flied actively for less than one minute in H. morosa, while males flied inactively and females did not fly at all in H. diomphalia. Once emerged, adults of the two species mated or fed on plant leaves and seemed to stay aboveground till dawn. H. mOTOsa adults were attracted to a blacklight trap mainly between 8 : 10-10 : 00 p.m. in the field. H. morosa males and females emerged from soil every other day in a glass cistern.

• Investigative Magnetic Resonance Imaging
• /
• v.22 no.2
• /
• pp.86-93
• /
• 2018

Purpose: Imaging plays a significant role in diagnosing leptomeningeal metastases. However, the most appropriate sequence for the detection of leptomeningeal metastases has yet to be determined. This study compares the efficacies of contrast-enhanced T2 fluid attenuated inversion recovery (FLAIR) and contrast-enhanced 3D T1 black-blood fast spin echo (FSE) imaging for the detection of leptomeningeal metastases. Materials and Methods: Tube phantoms containing varying concentrations of gadobutrol solution were scanned using T2 FLAIR and 3D T1 black-blood FSE. Additionally, 30 patients with leptomeningeal metastases were retrospectively evaluated to compare conspicuous lesions and the extent of leptomeningeal metastases detected by T2 FLAIR and 3D T1 black-blood FSE. Results: The signal intensities of low-concentration gadobutrol solutions (< 0.5 mmol/L) on T2 FLAIR images were higher than in 3D T1 black-blood FSE. The T2 FLAIR sequences exhibited significantly greater visual conspicuity scores than the 3D T1 black-blood sequence in leptomeningeal metastases of the pial membrane of cistern (P = 0.014). T2 FLAIR images exhibited a greater or equal extent (96.7%) of leptomeningeal metastases than 3D T1 black-blood FSE images. Conclusion: Because of its high sensitivity even at low gadolinium concentrations, contrast-enhanced T2 FLAIR images delineated leptomeningeal metastases in a wider territory than 3D T1 black-blood FSE.

• Journal of Korean Neurosurgical Society
• /
• v.30 no.sup2
• /
• pp.340-343
• /
• 2001

Arachnoid cysts are defined as duplicated arachnoids and their splitting with congenital, intra-arachnoid, and leptomeningeal malformations. They are most commonly located in the middle cranial fossa followed by suprasellar and quadrigeminal cisterns, posterior fossa, and very rare in cerebral convexities. They are often ruptured by trauma or spontaneously and cause subdural hygroma or subdural hematoma. Authors report a case of a 32-year-old woman with a convexity arachnoid cyst mimicking subdural hygroma associated with a separate middle fossa arachnoid cyst. Preoperatively, the convexity arachnoid cyst was misinterpreted as subdural hygroma resulted from a ruptured middle fossa cyst. The patient underwent craniotomy and cyst fenestration into the basal cistern. Two separate arachnoid cysts were found in the cerebral convexity and middle cranial fossa during the operation. Finally, cysts were resolved and she was discharged without any complication.

• Journal of Korean Neurosurgical Society
• /
• v.59 no.1
• /
• pp.58-61
• /
• 2016

Choroid plexus papillomas (CPPs) are relatively rare neuroectodermal tumors that develop from choroid plexus epithelial cells and are usually restricted to the ventricles. Extraventricular CPPs are very unusual and can be difficult to diagnose and treat. A 50-year-old male patient was admitted to our clinic complaining of headache and visual deterioration. Neurological examination found no abnormalities except decreased light perception and secondary optic atrophy in the left eye. Endocrine testing revealed normal levels of hormones produced by the pituitary and target glands. Magnetic resonance imaging of the brain revealed a huge regular-shaped lesion in the sellar-suprasellar region occupying the sella turcica and extending into the suprasellar cistern and planum sphenoidale. The lesion was completely excised by microsurgery via an ordinary left-sided pterional approach. Histopathology identified the lesion as a choroid plexus papilloma. Following the case report, literature on the origin, differential diagnosis, and treatment of this rare tumor is reviewed.

• Journal of Cerebrovascular and Endovascular Neurosurgery
• /
• v.25 no.1
• /
• pp.75-80
• /
• 2023

The prevalence of aneurysm formation in adults with Moyamoya disease (MMD) is higher than that in the general population. The treatment strategy is often individualized based on the patient's disease characteristics. A 22-year-old man was diagnosed with MMD after presenting a small thalamic intracerebral and subarachnoid hemorrhage in the quadrigeminal cistern. Cerebral angiography revealed a small aneurysm (2.42 mm) in the left anterior choroidal artery. Since the hemodynamics in the left hemisphere was compromised, an indirect bypass surgery was performed. The patient's condition deteriorated postoperatively because of poor perfusion of the internal carotid artery, and massive hydration was required. During neurocritical care, the aneurysm increased in size (5.33 mm). An observation strategy was adopted because of the distal aneurysmal location and the high risk involved. Subsequently, the patient recovered, and newly developed collateral flow appeared from the external carotid artery. Additionally, a dramatic size reduction of the aneurysm (1.51 mm) was noticed. Our case suggests that MMD-related dissecting aneurysms on a distal cerebral artery, which present a high risk of embolization, could be managed by indirectly reducing the hemodynamic burden. Massive hydration in such cases should be avoided or balanced to avoid the risk of rapid growth and aneurysm rupture.

• Journal of Korean Neurosurgical Society
• /
• v.51 no.5
• /
• pp.268-271
• /
• 2012

Objective : To propose grading of intracerebral hemorrhage (ICH) in ruptured middle cerebral artery (MCA) aneurysms, which helps to predict the prognosis more accurately. Methods : From August 2005 to December 2010, 27 cases of emergent hematoma evacuation and aneurysm clipping for MCA aneurysms were done in the author's clinic. Three variables were considered in grading the ICH, which were 1) hematoma volume, 2) diffuse subarachnoid hemorrhage (SAH) that extends to the contralateral sylvian cistern, and 3) the presence of midline shifting from computed tomography findings. For hematoma volume of greater than 25 mL, we assigned 2 points whereas 1 point for less than 25 cc. We also assigned 1 point for the presence of diffuse SAH whereas 0 point for the absence of it. Then, 1 point was assigned for midline shifting of greater than 5 mm whereas 0 point for less than 5 mm. Results : According to the grading system, the numbers of patients from grade 1 to 4 were 4, 6, 8 and 9 respectively and 5, 7, 8, 4 and 3 patients belonged to Glasgow Outcome Scale (GOS) 5 to 1 respectively. It was found that the patients with higher GOS had lower ICH grade which were confirmed to be statistically significant (p<0.01). Preoperative Hunt and Hess grade and absence of midline shifting were the factors to predict favorable outcome. Conclusion : The ICH grading system composed of above three variables was helpful in predicting the patient's outcome more accurately.